Marine Drugs

17 pages, 4640 KiB

Open AccessArticle

Novel Antioxidant Peptides Identified from Arthrospira platensis Hydrolysates Prepared by a Marine Bacterium Pseudoalteromonas sp. JS4-1 Extracellular Protease

by Congling Liu, Gong Chen, Hailian Rao, Xun Xiao, Yidan Chen, Cuiling Wu, Fei Bian and Hailun He

Mar. Drugs 2023, 21(2), 133; https://doi.org/10.3390/md21020133 - 20 Feb 2023

Cited by 2 | Viewed by 1642

Abstract

Crude enzymes produced by a marine bacterium Pseudoalteromonas sp. JS4-1 were used to hydrolyze phycobiliprotein. Enzymatic productions showed good performance on DPPH radical and hydroxyl radical scavenging activities (45.14 ± 0.43% and 65.11 ± 2.64%, respectively), especially small peptides with MWCO <3 kDa. [...] Read more.

Crude enzymes produced by a marine bacterium Pseudoalteromonas sp. JS4-1 were used to hydrolyze phycobiliprotein. Enzymatic productions showed good performance on DPPH radical and hydroxyl radical scavenging activities (45.14 ± 0.43% and 65.11 ± 2.64%, respectively), especially small peptides with MWCO <3 kDa. Small peptides were fractioned to four fractions using size-exclusion chromatography and the second fraction (F2) had the highest activity in hydroxyl radical scavenging ability (62.61 ± 5.80%). The fraction F1 and F2 both exhibited good antioxidant activities in oxidative stress models in HUVECs and HaCaT cells. Among them, F2 could upregulate the activities of SOD and GSH-Px and reduce the lipid peroxidation degree to scavenge the ROS to protect Caenorhabditis elegans under adversity. Then, 25 peptides total were identified from F2 by LC-MS/MS, and the peptide with the new sequence of INSSDVQGKY as the most significant component was synthetized and the ORAC assay and cellular ROS scavenging assay both illustrated its excellent antioxidant property. Full article

(This article belongs to the Special Issue Marine Bioactive Compounds against Oxidative Stress and Inflammation)

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17 pages, 3552 KiB

Open AccessArticle

Anti-Proliferative and Pro-Apoptotic vLMW Fucoidan Formulas Decrease PD-L1 Surface Expression in EBV Latency III and DLBCL Tumoral B-Cells by Decreasing Actin Network

by Jennifer Saliba, Chanez Manseur, Hugo Groult, Hussein Akil, Mona Tannoury, Danielle Troutaud, Thierry Maugard, Jean Feuillard, Ingrid Arnaudin and Chantal Jayat-Vignoles

Mar. Drugs 2023, 21(2), 132; https://doi.org/10.3390/md21020132 - 18 Feb 2023

Cited by 1 | Viewed by 2961

Abstract

Epstein–Barr virus (EBV) infects 95% of the world’s population and persists latently in the body. It immortalizes B-cells and is associated with lymphomas. LCLs (lymphoblastoid cell lines, EBV latency III B-cells) inhibit anti-tumoral T-cell response following PD-L1 overexpression (programmed death-ligand 1 immune checkpoint). [...] Read more.

Epstein–Barr virus (EBV) infects 95% of the world’s population and persists latently in the body. It immortalizes B-cells and is associated with lymphomas. LCLs (lymphoblastoid cell lines, EBV latency III B-cells) inhibit anti-tumoral T-cell response following PD-L1 overexpression (programmed death-ligand 1 immune checkpoint). Many cancer cells, including some DLBCLs (diffuse large B-cell lymphomas), also overexpress PD-L1. Immunotherapies are based on inhibition of PD-L1/PD-1 interactions but present some dose-dependent toxicities. We aim to find new strategies to improve their efficiency by decreasing PD-L1 expression. Fucoidan, a polysaccharide extracted from brown seaweed, exhibits immunomodulatory and anti-tumor activities depending on its polymerization degree, but data are scarce on lymphoma cells or immune checkpoints. LCLs and DLBCLs cells were treated with native fucoidan (Fucus vesiculosus) or original very-low-molecular-weight fucoidan formulas (vLMW-F). We observed cell proliferation decrease and apoptosis induction increase with vLMW-F and no toxicity on normal B- and T-cells. We highlighted a decrease in transcriptional and PD-L1 surface expression, even more efficient for vLMW than native fucoidan. This can be explained by actin network alteration, suggesting lower fusion of secretory vesicles carrying PD-L1 with the plasma membrane. We propose vLMW-F as potential adjuvants to immunotherapy due to their anti-proliferative and proapoptotic effects and ability to decrease PD-L1 membrane expression. Full article

(This article belongs to the Topic Antitumor Activity of Natural Products and Related Compounds)

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16 pages, 657 KiB

Open AccessArticle

Identification of ACE I-Inhibitory Peptides Released by the Hydrolysis of Tub Gurnard (Chelidonichthys lucerna) Skin Proteins and the Impact of Their In Silico Gastrointestinal Digestion

by Hajer Bougatef, Cristina de la Vega-Fernández, Assaad Sila, Ali Bougatef and Oscar Martínez-Alvarez

Mar. Drugs 2023, 21(2), 131; https://doi.org/10.3390/md21020131 - 17 Feb 2023

Cited by 5 | Viewed by 1442

Abstract

Tub gurnard is a highly abundant fishery species caught as a discard in the Mediterranean Sea. This work proposes its valorisation through the release of potential antihypertensive peptides and glycosaminoglycans (GAGs) through the controlled hydrolysis of tub gurnard skin proteins. Four proteases (Esperase, [...] Read more.

Tub gurnard is a highly abundant fishery species caught as a discard in the Mediterranean Sea. This work proposes its valorisation through the release of potential antihypertensive peptides and glycosaminoglycans (GAGs) through the controlled hydrolysis of tub gurnard skin proteins. Four proteases (Esperase, Alcalase, Trypsin and Pronase E) were used to obtain potent angiotensin converting enzyme I (ACE)-inhibitory hydrolysates. Peptides and GAGs were separated and evaluated for their antihypertensive potential by fluorometry. The peptide-rich fractions derived from the Esperase and Alcalase hydrolysates showed very low IC₅₀ values (47 and 68 μg/mL, respectively). Only the GAGs from the Trypsin and Esperase hydrolysates were relevant ACE inhibitors (63 and 52% at 1 mg/mL, respectively). The peptide composition of the most potent ACE-inhibitory fractions derived from the Esperase and Alcalase hydrolysates (IC₅₀ values of 33 and 29 μg/mL, respectively) was analysed by RP-LC-ESI-MS/MS. The analysis suggests that the ACE-inhibitory activity is related to the peptide hydrophobicity, as well as to the presence of specific residues at any of the last four C-terminal positions. The in silico gastrointestinal digestion of these fractions yielded small peptides with antihypertensive potential. Full article

(This article belongs to the Special Issue Sustainable Valorization of Seafood By-Products through Recovery of Valuable Bioactive Compounds)

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17 pages, 6576 KiB

Open AccessArticle

Crustin Defense against Vibrio parahaemolyticus Infection by Regulating Intestinal Microbial Balance in Litopenaeus vannamei

by Xinjia Lv, Shihao Li, Yang Yu, Xiaojun Zhang and Fuhua Li

Mar. Drugs 2023, 21(2), 130; https://doi.org/10.3390/md21020130 - 17 Feb 2023

Cited by 3 | Viewed by 1800

Abstract

Crustins are a kind of antimicrobial peptide (AMP) that exist in crustaceans. Some crustins do not have direct antimicrobial activity but exhibit in vivo defense functions against Vibrio. However, the underlying molecular mechanism is not clear. Here, the regulatory mechanism was partially [...] Read more.

Crustins are a kind of antimicrobial peptide (AMP) that exist in crustaceans. Some crustins do not have direct antimicrobial activity but exhibit in vivo defense functions against Vibrio. However, the underlying molecular mechanism is not clear. Here, the regulatory mechanism was partially revealed along with the characterization of the immune function of a type I crustin, LvCrustin I-2, from Litopenaeus vannamei. LvCrustin I-2 was mainly detected in hemocytes, intestines and gills and was apparently up-regulated after Vibrio parahaemolyticus infection. Although the recombinant LvCrustin I-2 protein possessed neither antibacterial activity nor agglutinating activity, the knockdown of LvCrustin I-2 accelerated the in vivo proliferation of V. parahaemolyticus. Microbiome analysis showed that the balance of intestinal microbiota was impaired after LvCrustin I-2 knockdown. Further transcriptome analysis showed that the intestinal epithelial barrier and immune function were impaired in shrimp after LvCrustin I-2 knockdown. After removing the intestinal bacteria via antibiotic treatment, the phenomenon of impaired intestinal epithelial barrier and immune function disappeared in shrimp after LvCrustin I-2 knockdown. This indicated that the impairment of the shrimp intestine after LvCrustin I-2 knockdown was caused by the dysbiosis of the intestinal microbiota. The present data suggest that crustins could resist pathogen infection through regulating the intestinal microbiota balance, which provides new insights into the functional mechanisms of antimicrobial peptides during pathogen infection. Full article

(This article belongs to the Special Issue Antibiotics from Marine Organisms 2023)

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19 pages, 3609 KiB

Open AccessArticle

Bioactivity Profiling and Untargeted Metabolomics of Microbiota Associated with Mesopelagic Jellyfish Periphylla periphylla

by Ernest Oppong-Danquah, Martina Miranda, Martina Blümel and Deniz Tasdemir

Mar. Drugs 2023, 21(2), 129; https://doi.org/10.3390/md21020129 - 17 Feb 2023

Cited by 2 | Viewed by 2646

Abstract

The marine mesopelagic zone extends from water depths of 200 m to 1000 m and is home to a vast number and diversity of species. It is one of the least understood regions of the marine environment with untapped resources of pharmaceutical relevance. [...] Read more.

The marine mesopelagic zone extends from water depths of 200 m to 1000 m and is home to a vast number and diversity of species. It is one of the least understood regions of the marine environment with untapped resources of pharmaceutical relevance. The mesopelagic jellyfish Periphylla periphylla is a well-known and widely distributed species in the mesopelagic zone; however, the diversity or the pharmaceutical potential of its cultivable microbiota has not been explored. In this study, we isolated microorganisms associated with the inner and outer umbrella of P. periphylla collected in Irminger Sea by a culture-dependent approach, and profiled their chemical composition and biological activities. Sixteen mostly gram-negative bacterial isolates were selected and subjected to an OSMAC cultivation regime approach using liquid and solid marine broth (MB) and glucose–yeast–malt (GYM) media. Their ethyl acetate (EtOAc) extracts were assessed for cytotoxicity and antimicrobial activity against fish and human pathogens. All, except one extract, displayed diverse levels of antimicrobial activities. Based on low IC₅₀ values, four most bioactive gram-negative strains; Polaribacter sp. SU124, Shewanella sp. SU126, Psychrobacter sp. SU143 and Psychrobacter sp. SU137, were prioritized for an in-depth comparative and untargeted metabolomics analysis using feature-based molecular networking. Various chemical classes such as diketopiperazines, polyhydroxybutyrates (PHBs), bile acids and other lipids were putatively annotated, highlighting the biotechnological potential in P. periphylla-associated microbiota as well as gram-negative bacteria. This is the first study providing an insight into the cultivable bacterial community associated with the mesopelagic jellyfish P. periphylla and, indeed, the first to mine the metabolome and antimicrobial activities of these microorganisms. Full article

(This article belongs to the Special Issue Marine Metabolomics 2023)

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35 pages, 1495 KiB

Open AccessReview

Immunopotentiating Activity of Fucoidans and Relevance to Cancer Immunotherapy

by Yani Li, Eileen McGowan, Size Chen, Jerran Santos, Haibin Yin and Yiguang Lin

Mar. Drugs 2023, 21(2), 128; https://doi.org/10.3390/md21020128 - 15 Feb 2023

Cited by 6 | Viewed by 3119

Abstract

Fucoidans, discovered in 1913, are fucose-rich sulfated polysaccharides extracted mainly from brown seaweed. These versatile and nontoxic marine-origin heteropolysaccharides have a wide range of favorable biological activities, including antitumor, immunomodulatory, antiviral, antithrombotic, anticoagulant, antithrombotic, antioxidant, and lipid-lowering activities. In the early 1980s, fucoidans [...] Read more.

Fucoidans, discovered in 1913, are fucose-rich sulfated polysaccharides extracted mainly from brown seaweed. These versatile and nontoxic marine-origin heteropolysaccharides have a wide range of favorable biological activities, including antitumor, immunomodulatory, antiviral, antithrombotic, anticoagulant, antithrombotic, antioxidant, and lipid-lowering activities. In the early 1980s, fucoidans were first recognized for their role in supporting the immune response and later, in the 1990s, their effects on immune potentiation began to emerge. In recent years, the understanding of the immunomodulatory effects of fucoidan has expanded significantly. The ability of fucoidan(s) to activate CTL-mediated cytotoxicity against cancer cells, strong antitumor property, and robust safety profile make fucoidans desirable for effective cancer immunotherapy. This review focusses on current progress and understanding of the immunopotentiation activity of various fucoidans, emphasizing their relevance to cancer immunotherapy. Here, we will discuss the action of fucoidans in different immune cells and review how fucoidans can be used as adjuvants in conjunction with immunotherapeutic products to improve cancer treatment and clinical outcome. Some key rationales for the possible combination of fucoidans with immunotherapy will be discussed. An update is provided on human clinical studies and available registered cancer clinical trials using fucoidans while highlighting future prospects and challenges. Full article

(This article belongs to the Special Issue Marine Natural Products as Anticancer Agents 2.0)

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16 pages, 4086 KiB

Open AccessArticle

New Pyrroline Isolated from Antarctic Krill-Derived Actinomycetes Nocardiopsis sp. LX-1 Combining with Molecular Networking

by Ting Shi, Yan-Jing Li, Ze-Min Wang, Yi-Fei Wang, Bo Wang and Da-Yong Shi

Mar. Drugs 2023, 21(2), 127; https://doi.org/10.3390/md21020127 - 15 Feb 2023

Cited by 1 | Viewed by 1933

Abstract

Antarctic krill (Euphausia superba) of the Euphausiidae family comprise one of the largest biomasses in the world and play a key role in the Antarctic marine ecosystem. However, the study of E. superba-derived microbes and their secondary metabolites has been [...] Read more.

Antarctic krill (Euphausia superba) of the Euphausiidae family comprise one of the largest biomasses in the world and play a key role in the Antarctic marine ecosystem. However, the study of E. superba-derived microbes and their secondary metabolites has been limited. Chemical investigation of the secondary metabolites of the actinomycetes Nocardiopsis sp. LX-1 (in the family of Nocardiopsaceae), isolated from E. superba, combined with molecular networking, led to the identification of 16 compounds a–p (purple nodes in the molecular network) and the isolation of one new pyrroline, nocarpyrroline A (1), along with 11 known compounds 2–12. The structure of the new compound 1 was elucidated by extensive spectroscopic investigation. Compound 2 exhibited broad-spectrum antibacterial activities against A. hydrophila, D. chrysanthemi, C. terrigena, X. citri pv. malvacearum and antifungal activity against C. albicans in a conventional broth dilution assay. The positive control was ciprofloxacin with the MIC values of <0.024 µM, 0.39 µM, 0.39 µM, 0.39 µM, and 0.20 µM, respectively. Compound 1 and compounds 7, 10, and 11 displayed antifungal activities against F. fujikuroi and D. citri, respectively, in modified agar diffusion test. Prochloraz was used as positive control and showed the inhibition zone radius of 17 mm and 15 mm against F. fujikuroi and D. citri, respectively. All the annotated compounds a–p by molecular networking were first discovered from the genus Nocardiopsis. Nocarpyrroline A (1) features an unprecedented 4,5-dihydro-pyrrole-2-carbonitrile substructure, and it is the first pyrroline isolated from the genus Nocardiopsis. This study further demonstrated the guiding significance of molecular networking in the research of microbial secondary metabolites. Full article

(This article belongs to the Special Issue Discovering Marine Bioactive Compounds by Molecular Networking)

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18 pages, 1188 KiB

Open AccessArticle

Transcriptome Sequencing of the Diatom Asterionellopsis thurstonii and In Silico Identification of Enzymes Potentially Involved in the Synthesis of Bioactive Molecules

by Eleonora Montuori, Kevin A. Martinez, Daniele De Luca, Adrianna Ianora and Chiara Lauritano

Mar. Drugs 2023, 21(2), 126; https://doi.org/10.3390/md21020126 - 15 Feb 2023

Cited by 2 | Viewed by 2133

Abstract

Microalgae produce a plethora of primary and secondary metabolites with possible applications in several market sectors, including cosmetics, human nutrition, aquaculture, biodiesel production and treatment/prevention of human diseases. Diatoms, in particular, are the most diversified microalgal group, many species of which are known [...] Read more.

Microalgae produce a plethora of primary and secondary metabolites with possible applications in several market sectors, including cosmetics, human nutrition, aquaculture, biodiesel production and treatment/prevention of human diseases. Diatoms, in particular, are the most diversified microalgal group, many species of which are known to have anti-cancer, anti-oxidant, anti-diabetes, anti-inflammatory and immunomodulatory properties. Compounds responsible for these activities are often still unknown. The aim of this study was to de novo sequence the full transcriptome of two strains of the diatom Asterionellopsis thurstonii, sampled from two different locations and cultured in both control and phosphate starvation conditions. We used an RNA-sequencing approach to in silico identify transcripts potentially involved in the synthesis/degradation of compounds with anti-cancer and immunomodulatory properties. We identified transcript coding for L-asparaginase I, polyketide cyclase/dehydrase, bifunctional polyketide phosphatase/kinase, 1-deoxy-D-xylulose-5-phosphate synthase (fragment), inositol polyphosphate 5-phosphatase INPP5B/F, catechol O-Methyltransferase, digalactosyldiacylglycerol synthase (DGD1), 1,2-diacylglycerol-3-beta-galactosyltransferase and glycerolphosphodiester phosphodiesterase. Differential expression analysis also allowed to identify in which culturing condition these enzymes are more expressed. Overall, these data give new insights on the annotation of diatom genes, enzymatic pathways involved in the generation of bioactive molecules and possible exploitation of Asterionellopsis thurstonii. Full article

(This article belongs to the Special Issue Bioinformatics of Marine Natural Products 2.0)

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19 pages, 2795 KiB

Open AccessArticle

Bioinformatics-Based Screening Approach for the Identification and Characterization of Lipolytic Enzymes from the Marine Diatom Phaeodactylum tricornutum

by Victor Murison, Josiane Hérault, Benoît Schoefs, Justine Marchand and Lionel Ulmann

Mar. Drugs 2023, 21(2), 125; https://doi.org/10.3390/md21020125 - 14 Feb 2023

Cited by 2 | Viewed by 1791

Abstract

Oleaginous diatoms accumulate lipids of biotechnological interest when exposed to nutrient stress conditions such as nitrogen starvation. While accumulation mechanisms are well-known and have been engineered to improve lipid production, degradation mechanisms remain poorly investigated in diatoms. Identifying lipid-degrading enzymes is the initial [...] Read more.

Oleaginous diatoms accumulate lipids of biotechnological interest when exposed to nutrient stress conditions such as nitrogen starvation. While accumulation mechanisms are well-known and have been engineered to improve lipid production, degradation mechanisms remain poorly investigated in diatoms. Identifying lipid-degrading enzymes is the initial step to understanding the catabolic processes. In this study, an in silico screening of the genome of Phaeodactylum tricornutum led to the identification of 57 putative triacylglycerol lipases (EC 3.1.1.3) grouped in 4 families. Further analysis revealed the presence of conserved domains and catalytic residues of lipases. Physico-chemical characteristics and subcellular localization predictions highlighted that a majority of these putative proteins are hydrophilic and cytosolic, suggesting they could be recruited to lipid droplets directly from the cytosol. Among the 57 identified putative proteins, three lipases were identified as possibly involved in lipophagy due to a potential vacuolar localization. The expression of the mRNA corresponding to the 57 proteins was then searched in 3 transcriptomic datasets obtained under nitrogen starvation. Nine genes were highly regulated and were considered as encoding enzymes with a probable important function in lipid catabolism. A tertiary structure prediction of these nine candidates yielded eight functional 3D models. Among those, two downregulated enzymes, Phatr3_J54974 and Phatr3_EG00720, were highlighted as good targets for future functional genomics and purification studies to investigate their role in lipid degradation. Full article

(This article belongs to the Special Issue Biotechnological Applications of Marine Enzymes)

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12 pages, 3388 KiB

Open AccessCommunication

Briavioids E–G, Newly Isolated Briarane-Diterpenoids from a Cultured Octocoral Briareum violaceum

by Thanh Hao Huynh, Chia-Jung Liu, Yi-Hung Liu, Su-Ying Chien, Zhi-Hong Wen, Lee-Shing Fang, Jih-Jung Chen, Yang-Chang Wu, Jui-Hsin Su and Ping-Jyun Sung

Mar. Drugs 2023, 21(2), 124; https://doi.org/10.3390/md21020124 - 14 Feb 2023

Cited by 1 | Viewed by 1583

Abstract

The chemical screening of a cultured soft coral, Briareum violaceum, led to the isolation of eight natural, briarane-related diterpenoids, including three unreported metabolites, briavioids E–G (1–3), and five known briaranes, briacavatolides B (4) and C ( [...] Read more.

The chemical screening of a cultured soft coral, Briareum violaceum, led to the isolation of eight natural, briarane-related diterpenoids, including three unreported metabolites, briavioids E–G (1–3), and five known briaranes, briacavatolides B (4) and C (5), briaexcavatin L (6), briaexcavatolide U (7) and briarenol K (8). The structures of briaranes 1–8 were established using spectroscopic methods. The absolute configuration of briavioid A (9), obtained in a previous study, was reported for the first time in this study by a single-crystal X-ray diffraction analysis using a copper radiation source. The anti-inflammatory activity of briaranes 1 and 2 and briaranes 4–8 was evaluated by screening their inhibitory ability against the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins in lipopolysaccharide (LPS)-induced RAW 264.7 macrophage cells. Full article

(This article belongs to the Special Issue Challenges on Structural Determination of Marine Natural Products)

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16 pages, 4352 KiB

Open AccessArticle

Inhibition of Polymicrobial Biofilms of Candida albicans–Staphylococcus aureus/Streptococcus mutans by Fucoidan–Gold Nanoparticles

by Nazia Tabassum, Fazlurrahman Khan, Min-Gyun Kang, Du-Min Jo, Kyung-Jin Cho and Young-Mog Kim

Mar. Drugs 2023, 21(2), 123; https://doi.org/10.3390/md21020123 - 13 Feb 2023

Cited by 5 | Viewed by 2052

Abstract

The polymicrobial proliferation and development of complex biofilm morphologies by bacterial and fungal pathogens in the host are some of the key factors contributing to the failure of antimicrobial treatments. The polymicrobial interaction of Candida albicans and some bacterial species has been extensively [...] Read more.

The polymicrobial proliferation and development of complex biofilm morphologies by bacterial and fungal pathogens in the host are some of the key factors contributing to the failure of antimicrobial treatments. The polymicrobial interaction of Candida albicans and some bacterial species has been extensively studied in both in vitro and in vivo model systems. Alternative strategies for disrupting polymicrobial interaction and biofilm formation are constantly needed. Among several alternative strategies, the use of nanoparticles synthesized using a natural product in the treatment of microbial infection has been considered a promising approach. The current study aimed to synthesize gold nanoparticles (AuNPs) using a natural product, fucoidan, and to test their efficacy against mono and duo combinations of fungal (Candida albicans) and bacterial (Staphylococcus aureus/Streptococcus mutans) biofilms. Several methods were used to characterize and study Fu–AuNPs, including UV-vis absorption spectroscopy, FTIR, FE-TEM, EDS, DLS, zeta potential, and XRD. The concentration-dependent inhibition of early-stage biofilms and the eradication of mature biofilms of single species of C. albicans, S. aureus, and S. mutans have been observed. Early biofilms of a dual-species combination of C. albicans and S. aureus/S. mutans were also suppressed at an increasing concentration of Fu–AuNPs. Furthermore, Fu–AuNPs significantly eradicated the established mature biofilm of mixed species. The treatment method proposed in this study, which involves the use of marine-bioinspired nanoparticles, is a promising and biocompatible agent for preventing the growth of polymicrobial biofilms of bacterial and fungal pathogens. Full article

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12 pages, 1580 KiB

Open AccessCommunication

Recovery of Fatty Acid and Volatile Flavor Compound Composition in Farmed Tiger Puffer (Takifugu rubripes) with a Fish Oil-Finishing Strategy

by Lin Li, Feiran Zhang, Xiaoxue Meng, Xishuai Cui, Qiang Ma, Yuliang Wei, Mengqing Liang and Houguo Xu

Mar. Drugs 2023, 21(2), 122; https://doi.org/10.3390/md21020122 - 13 Feb 2023

Cited by 4 | Viewed by 1156

Abstract

Booming fish farming results in a relative shortage of fish oil (FO) supply, meaning that alternative oils are increasingly used in fish feeds, which leads to reduction of long-chain polyunsaturated fatty acids (LC-PUFAs) and other relevant changes in fish products. This study investigated [...] Read more.

Booming fish farming results in a relative shortage of fish oil (FO) supply, meaning that alternative oils are increasingly used in fish feeds, which leads to reduction of long-chain polyunsaturated fatty acids (LC-PUFAs) and other relevant changes in fish products. This study investigated the efficacy of an FO-finishing strategy in recovering the muscle quality of farmed tiger puffer. An eight-week feeding trial (growing-out period) was conducted with five experimental diets, in which graded levels (0 (control), 25, 50, 75, and 100%) of added FO were replaced by poultry oil (PO). Following the growing-out period was a four-week FO-finishing period, during which fish in all groups were fed the control diet. Dietary PO significantly decreased the muscle LC-PUFA content, whereas in general, the FO-finishing strategy recovered it to a level comparable with that of the group fed FO continuously. The recovery efficiency of EPA was higher than that of DHA. Dietary PO also led to changes of volatile flavor compounds in the muscle, such as butanol, pentenal, and hexenal, whereas the FO-finishing strategy mitigated the changes. In conclusion, the FO-finishing strategy is promising in recovering the LC-PUFA and volatile-flavor-compound composition in farmed tiger puffer after the feeding of PO-based diets. Full article

(This article belongs to the Special Issue Fatty Acids from Marine Organisms)

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13 pages, 17757 KiB

Open AccessArticle

Anti-Pollutant Activity of Porphyra yezoensis Water Extract and Its Active Compound, Porphyra 334, against Urban Particulate Matter-Induced Keratinocyte Cell Damage

by Seoyoung Choi, Jeong Hun Lee, Sae Woong Oh, Eunbi Yu, Kitae Kwon, Sung Joo Jang, Dong Sun Shin, Sang Hyun Moh and Jongsung Lee

Mar. Drugs 2023, 21(2), 121; https://doi.org/10.3390/md21020121 - 13 Feb 2023

Viewed by 1854

Abstract

Urban particulate matter (UPM) causes skin aging and inflammatory reactions by influencing skin cells through the aryl hydrocarbon receptor (AhR) signaling pathway. Porphyra yezoensis (also known as Pyropia yezoensis), a red alga belonging to the Bangiaceae family, is an edible red seaweed. [...] Read more.

Urban particulate matter (UPM) causes skin aging and inflammatory reactions by influencing skin cells through the aryl hydrocarbon receptor (AhR) signaling pathway. Porphyra yezoensis (also known as Pyropia yezoensis), a red alga belonging to the Bangiaceae family, is an edible red seaweed. Here, we examined the anti-pollutant effect of P. yezoensis water extract. While UPM treatment induced xenobiotic response element (XRE) promoter luciferase activity, P. yezoensis water extract reduced UPM-induced XRE activity. Next, we isolated an active compound from P. yezoensis and identified it as porphyra 334. Similar to the P. yezoensis water extract, porphyra 334 attenuated UPM-induced XRE activity. Moreover, although UPM augmented AhR nuclear translocation, which led to an increase in cytochrome P450 1A1 (CYP1A1) mRNA levels, these effects were reduced by porphyra 334. Moreover, UPM induced the production of reactive oxygen species (ROS) and reduced cell proliferation. These effects were attenuated in response to porphyra 334 treatment. Furthermore, our results revealed that the increased ROS levels induced by UPM treatment induced transient receptor potential vanilloid 1 (TRPV1) activity, which is related to skin aging and inflammatory responses. However, porphyra 334 treatment reduced this reaction by inhibiting ROS production induced by CYP1A1 activation. This indicates that porphyra 334, an active compound of P. yezoensis, attenuates UP-induced cell damage by inhibiting AhR-induced ROS production, which results in a reduction in TRPV1 activation, leading to cell proliferation. This also suggests that porphyra 334 could protect the epidermis from harmful pollutants. Full article

(This article belongs to the Special Issue Bioactive Compounds for Marine-Derived Cosmeceuticals against Skin Diseases 2.0)

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21 pages, 4498 KiB

Open AccessEditor’s ChoiceReview

Marine Organisms as a Prolific Source of Bioactive Depsipeptides

by Mingyuan Zeng, Jianyun Tao, Shuang Xu, Xuelian Bai and Huawei Zhang

Mar. Drugs 2023, 21(2), 120; https://doi.org/10.3390/md21020120 - 11 Feb 2023

Cited by 6 | Viewed by 1818

Abstract

Depsipeptides, an important group of polypeptides containing residues of hydroxy acids and amino acids linked together by amide and ester bonds, have potential applications in agriculture and medicine. A growing body of evidence demonstrates that marine organisms are prolific sources of depsipeptides, such [...] Read more.

Depsipeptides, an important group of polypeptides containing residues of hydroxy acids and amino acids linked together by amide and ester bonds, have potential applications in agriculture and medicine. A growing body of evidence demonstrates that marine organisms are prolific sources of depsipeptides, such as marine cyanobacteria, sponges, mollusks, microorganisms and algae. However, these substances have not yet been comprehensively summarized. In order to enrich our knowledge about marine depsipeptides, their biological sources and structural features, as well as bioactivities, are highlighted in this review after an extensive literature search and data analysis. Full article

(This article belongs to the Special Issue Marine Bioactive Peptides: Structure, Function, and Therapeutic Potential IV)

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21 pages, 5094 KiB

Open AccessArticle

Transfection of Sponge Cells and Intracellular Localization of Cancer-Related MYC, RRAS2, and DRG1 Proteins

by Kristina Dominko, Antea Talajić, Martina Radić, Nikolina Škrobot Vidaček, Kristian Vlahoviček, Maja Herak Bosnar and Helena Ćetković

Mar. Drugs 2023, 21(2), 119; https://doi.org/10.3390/md21020119 - 10 Feb 2023

Cited by 2 | Viewed by 2113

Abstract

The determination of the protein’s intracellular localization is essential for understanding its biological function. Protein localization studies are mainly performed on primary and secondary vertebrate cell lines for which most protocols have been optimized. In spite of experimental difficulties, studies on invertebrate cells, [...] Read more.

The determination of the protein’s intracellular localization is essential for understanding its biological function. Protein localization studies are mainly performed on primary and secondary vertebrate cell lines for which most protocols have been optimized. In spite of experimental difficulties, studies on invertebrate cells, including basal Metazoa, have greatly advanced. In recent years, the interest in studying human diseases from an evolutionary perspective has significantly increased. Sponges, placed at the base of the animal tree, are simple animals without true tissues and organs but with a complex genome containing many genes whose human homologs have been implicated in human diseases, including cancer. Therefore, sponges are an innovative model for elucidating the fundamental role of the proteins involved in cancer. In this study, we overexpressed human cancer-related proteins and their sponge homologs in human cancer cells, human fibroblasts, and sponge cells. We demonstrated that human and sponge MYC proteins localize in the nucleus, the RRAS2 in the plasma membrane, the membranes of the endolysosomal vesicles, and the DRG1 in the cell’s cytosol. Despite the very low transfection efficiency of sponge cells, we observed an identical localization of human proteins and their sponge homologs, indicating their similar cellular functions. Full article

(This article belongs to the Section Marine Biotechnology Related to Drug Discovery or Production)

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18 pages, 5085 KiB

Open AccessPerspective

Unifying the Synthesis of a Whole Family of Marine Meroterpenoids through a Biosynthetically Inspired Sequence of 1,2-Hydride and Methyl Shifts as Key Step

by Antonio Rosales Martínez, Román Nicolay Rodríguez-Maecker and Ignacio Rodríguez-García

Mar. Drugs 2023, 21(2), 118; https://doi.org/10.3390/md21020118 - 10 Feb 2023

Viewed by 1277

Abstract

Marine meroterpenoids have attracted a great deal of attention from synthetic research groups due to their attractive and varied biological activities and their unique and diverse structures. In most cases, however, further biological studies have been severely limited mainly to the scarcity of [...] Read more.

Marine meroterpenoids have attracted a great deal of attention from synthetic research groups due to their attractive and varied biological activities and their unique and diverse structures. In most cases, however, further biological studies have been severely limited mainly to the scarcity of natural supply and because almost none of the reported syntheses methods has enabled unified access for a large number of marine meroterpenoids with aureane and avarane skeletons. Based on our previous publications and the study of recent manuscripts on marine meroterpenoids, we have conceived a unified strategy for these fascinating marine compounds with aureane or avarane skeletons using available drimane compounds as starting materials. The key step is a biosynthetic sequence of 1,2-hydride and methyl shifts. This strategy is of great synthetic value to access marine meroterpenoids through easy chemical synthetic procedures. Finally, several retrosynthetic proposals are made for the future synthesis of several members of this class of meroterpenoids, focused on consolidating these 1,2-rearrangements as a versatile and unified strategy that could be widely used in the preparation of these marine meroterpenoids. Full article

(This article belongs to the Special Issue Characterization of Structure-Activity Relationships in Marine Natural Products)

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17 pages, 2706 KiB

Open AccessArticle

Phytochemical Investigation of Three Cystoseira Species and Their Larvicidal Activity Supported with In Silico Studies

by Shaza H. Aly, Ahmed M. Elissawy, Dina Salah, Nawal Abdulaziz Alfuhaid, Ola H. Zyaan, Hany I. Mohamed, Abdel Nasser B. Singab and Shaimaa M. Farag

Mar. Drugs 2023, 21(2), 117; https://doi.org/10.3390/md21020117 - 10 Feb 2023

Cited by 13 | Viewed by 2090

Abstract

Culex pipiens mosquitoes are transmitters of many viruses and are associated with the transmission of many diseases, such as filariasis and avian malaria, that have a high rate of mortality. The current study draws attention to the larvicidal efficacy of three methanolic algal [...] Read more.

Culex pipiens mosquitoes are transmitters of many viruses and are associated with the transmission of many diseases, such as filariasis and avian malaria, that have a high rate of mortality. The current study draws attention to the larvicidal efficacy of three methanolic algal extracts, Cystoseira myrica, C. trinodis, and C. tamariscifolia, against the third larval instar of Cx. pipiens. The UPLC-ESI-MS analysis of three methanol fractions of algal samples led to the tentative characterization of twelve compounds with different percentages among the three samples belonging to phenolics and terpenoids. Probit analysis was used to calculate the lethal concentrations (LC₅₀ and LC₉₀). The highest level of toxicity was attained after treatment with C. myrica extract using a lethal concentration 50 (LC₅₀) of 105.06 ppm, followed by C. trinodis (135.08 ppm), and the lowest level of toxicity was achieved by C. tamariscifolia (138.71 ppm) after 24 h. The elevation of glutathione-S-transferase (GST) and reduction of acetylcholine esterase (AChE) enzymes confirm the larvicidal activity of the three algal extracts. When compared to untreated larvae, all evaluated extracts revealed a significant reduction in protein, lipid, and carbohydrate contents, verifying their larvicidal effectiveness. To further support the observed activity, an in silico study for the identified compounds was carried out on the two tested enzymes. Results showed that the identified compounds and the tested enzymes had excellent binding affinities for each other. Overall, the current work suggests that the three algal extractions are a prospective source for the development of innovative, environmentally friendly larvicides. Full article

(This article belongs to the Special Issue Marine Compounds and Research of the Middle East 2nd Edition)

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3 pages, 184 KiB

Open AccessEditorial

Marine Compounds from the Far Eastern Organisms

by Sergey A. Dyshlovoy, Timofey V. Malyarenko, Olesya I. Zhuravleva, Hiroshi Tomoda and Maxim E. Zhidkov

Mar. Drugs 2023, 21(2), 116; https://doi.org/10.3390/md21020116 - 09 Feb 2023

Cited by 1 | Viewed by 1167

Abstract

The term “Far East” implies a huge geographical region that consists of Eastern and Southeastern Asia, Eastern Russia and includes the waters of two oceans—the Pacific and Indian [...] Full article

(This article belongs to the Special Issue Marine Compounds from the Far Eastern Organisms)

22 pages, 4171 KiB

Open AccessArticle

Fucoidan from Fucus vesiculosus: Evaluation of the Impact of the Sulphate Content on Nanoparticle Production and Cell Toxicity

by Noelia Flórez-Fernández, Jorge F. Pontes, Filipa Guerreiro, Inês T. Afonso, Giovanna Lollo, Maria Dolores Torres, Herminia Domínguez, Ana M. Rosa da Costa and Ana Grenha

Mar. Drugs 2023, 21(2), 115; https://doi.org/10.3390/md21020115 - 07 Feb 2023

Cited by 5 | Viewed by 2235

Abstract

The composition of seaweeds is complex, with vitamins, phenolic compounds, minerals, and polysaccharides being some of the factions comprising their structure. The main polysaccharide in brown seaweeds is fucoidan, and several biological activities have been associated with its structure. Chitosan is another marine [...] Read more.

The composition of seaweeds is complex, with vitamins, phenolic compounds, minerals, and polysaccharides being some of the factions comprising their structure. The main polysaccharide in brown seaweeds is fucoidan, and several biological activities have been associated with its structure. Chitosan is another marine biopolymer that is very popular in the biomedical field, owing to its suitable features for formulating drug delivery systems and, particularly, particulate systems. In this work, the ability of fucoidan to produce nanoparticles was evaluated, testing different amounts of a polymer and using chitosan as a counterion. Nanoparticles of 200–300 nm were obtained when fucoidan prevailed in the formulation, which also resulted in negatively charged nanoparticles. Adjusting the pH of the reaction media to 4 did not affect the physicochemical characteristics of the nanoparticles. The IC₅₀ of fucoidan was determined, in both HCT−116 and A549 cells, to be around 160 µg/mL, whereas it raised to 675–100 µg/mL when nanoparticles (fucoidan/chitosan = 2/1, w/w) were tested. These marine materials (fucoidan and chitosan) provided features suitable to formulate polymeric nanoparticles to use in biomedical applications. Full article

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14 pages, 869 KiB

Open AccessArticle

Chilensosides E, F, and G—New Tetrasulfated Triterpene Glycosides from the Sea Cucumber Paracaudina chilensis (Caudinidae, Molpadida): Structures, Activity, and Biogenesis

by Alexandra S. Silchenko, Sergey A. Avilov, Roman S. Popov, Pavel S. Dmitrenok, Ekaterina A. Chingizova, Boris B. Grebnev, Anton B. Rasin and Vladimir I. Kalinin

Mar. Drugs 2023, 21(2), 114; https://doi.org/10.3390/md21020114 - 05 Feb 2023

Cited by 1 | Viewed by 1978

Abstract

Three new tetrasulfated triterpene glycosides, chilensosides E (1), F (2), and G (3), have been isolated from the Far-Eastern sea cucumber Paracaudina chilensis (Caudinidae, Molpadida). The structures were established based on extensive analysis of 1D and 2D [...] Read more.

Three new tetrasulfated triterpene glycosides, chilensosides E (1), F (2), and G (3), have been isolated from the Far-Eastern sea cucumber Paracaudina chilensis (Caudinidae, Molpadida). The structures were established based on extensive analysis of 1D and 2D NMR spectra and confirmed by HR-ESI-MS data. The compounds differ in their carbohydrate chains, namely in the number of monosaccharide residues (five or six) and in the positions of sulfate groups. Chilensosides E (1) and F (2) are tetrasulfated pentaosides with the position of one of the sulfate groups at C-3 Glc3, and chilensoside G (3) is a tetrasulfated hexaoside. The biogenetic analysis of the glycosides of P. chilensis has revealed that the structures form a network due to the attachment of sulfate groups to almost all possible positions. The upper semi-chain is sulfated earlier in the biosynthetic process than the lower one. Noticeably, the presence of a sulfate group at C-3 Glc3—a terminal monosaccharide residue in the bottom semi-chain of compounds 1 and 2—excludes the possibility of this sugar chain’s further elongation. Presumably, the processes of glycosylation and sulfation are concurrent biosynthetic stages. They can be shifted in time in relation to each other, which is a characteristic feature of the mosaic type of biosynthesis. The hemolytic action of compounds 1–3 against human erythrocytes and cytotoxic activities against five human cancer cell lines were tested. The compounds showed moderate hemolytic activity but were inactive against cancer cells, probably because of their structural peculiarities, such as the combination of positions of four sulfate groups. Full article

(This article belongs to the Special Issue Honoring Prof. Dr. Valentin A. Stonik for His Outstanding Contribution to Marine Natural Product Chemistry on the Occasion of His 80th Birthday)

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17 pages, 3178 KiB

Open AccessArticle

Antinociceptive Effects of Aaptamine, a Sponge Component, on Peripheral Neuropathy in Rats

by Chun-Sung Sung, Hao-Jung Cheng, Nan-Fu Chen, Shih-Hsuan Tang, Hsiao-Mei Kuo, Ping-Jyun Sung, Wu-Fu Chen and Zhi-Hong Wen

Mar. Drugs 2023, 21(2), 113; https://doi.org/10.3390/md21020113 - 04 Feb 2023

Cited by 3 | Viewed by 1761

Abstract

Aaptamine, a natural marine compound isolated from the sea sponge, has various biological activities, including delta-opioid agonist properties. However, the effects of aaptamine in neuropathic pain remain unclear. In the present study, we used a chronic constriction injury (CCI)-induced peripheral neuropathic rat model [...] Read more.

Aaptamine, a natural marine compound isolated from the sea sponge, has various biological activities, including delta-opioid agonist properties. However, the effects of aaptamine in neuropathic pain remain unclear. In the present study, we used a chronic constriction injury (CCI)-induced peripheral neuropathic rat model to explore the analgesic effects of intrathecal aaptamine administration. We also investigated cellular angiogenesis and lactate dehydrogenase A (LDHA) expression in the ipsilateral lumbar spinal cord after aaptamine administration in CCI rats by immunohistofluorescence. The results showed that aaptamine alleviates CCI-induced nociceptive sensitization, allodynia, and hyperalgesia. Moreover, aaptamine significantly downregulated CCI-induced vascular endothelial growth factor (VEGF), cluster of differentiation 31 (CD31), and LDHA expression in the spinal cord. Double immunofluorescent staining showed that the spinal VEGF and LDHA majorly expressed on astrocytes and neurons, respectively, in CCI rats and inhibited by aaptamine. Collectively, our results indicate aaptamine’s potential as an analgesic agent for neuropathic pain. Furthermore, inhibition of astrocyte-derived angiogenesis and neuronal LDHA expression might be beneficial in neuropathy. Full article

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23 pages, 1284 KiB

Open AccessFeature PaperReview

Fucoidan in Pharmaceutical Formulations: A Comprehensive Review for Smart Drug Delivery Systems

by Yusuf A. Haggag, Abeer A. Abd Elrahman, Roland Ulber and Ahmed Zayed

Mar. Drugs 2023, 21(2), 112; https://doi.org/10.3390/md21020112 - 04 Feb 2023

Cited by 24 | Viewed by 6099

Abstract

Fucoidan is a heterogeneous group of polysaccharides isolated from marine organisms, including brown algae and marine invertebrates. The physicochemical characteristics and potential bioactivities of fucoidan have attracted substantial interest in pharmaceutical industries in the past few decades. These polysaccharides are characterized by possessing [...] Read more.

Fucoidan is a heterogeneous group of polysaccharides isolated from marine organisms, including brown algae and marine invertebrates. The physicochemical characteristics and potential bioactivities of fucoidan have attracted substantial interest in pharmaceutical industries in the past few decades. These polysaccharides are characterized by possessing sulfate ester groups that impart negatively charged surfaces, low/high molecular weight, and water solubility. In addition, various promising bioactivities have been reported, such as antitumor, immunomodulatory, and antiviral effects. Hence, the formulation of fucoidan has been investigated in the past few years in diverse pharmaceutical dosage forms to be able to reach their site of action effectively. Moreover, they can act as carriers for various drugs in value-added drug delivery systems. The current work highlights the attractive biopharmaceutical properties of fucoidan being formulated in oral, inhalable, topical, injectable, and other advanced formulations treating life-quality-affecting diseases. Therefore, the present work points out the current status of fucoidan pharmaceutical formulations for future research transferring their application from in vitro and in vivo studies to clinical application and market availability. Full article

(This article belongs to the Special Issue Fucoidans: From Production to Application)

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17 pages, 3731 KiB

Open AccessArticle

Proteomic Identification of Plasma Components in Tachypleus tridentatus and Their Effects on the Longitudinal Bone Growth Rate in Rats

by Shu Jiang, Xinjian Qu, Siping Liu, Jun Wei, Xiangxi Yi, Yonghong Liu and Chenghai Gao

Mar. Drugs 2023, 21(2), 111; https://doi.org/10.3390/md21020111 - 03 Feb 2023

Cited by 2 | Viewed by 1380

Abstract

Tachypleus tridentatus (T. tridentatus) is a marine animal and traditional Chinese medicine. T. tridentatus plasma is a valuable resource for important medical and health-based functions. In this experiment, in order to evaluate the effect and mechanism of T. tridentatus plasma with [...] Read more.

Tachypleus tridentatus (T. tridentatus) is a marine animal and traditional Chinese medicine. T. tridentatus plasma is a valuable resource for important medical and health-based functions. In this experiment, in order to evaluate the effect and mechanism of T. tridentatus plasma with respect to the promotion of bone tissue growth in rats, the processes of ultrafiltration and mass spectrometry were first used to separate and identify the components of T. tridentatus plasma. Then, a comparison of the effects of the T. tridentatus plasma samples, which each possessed different molecular weights, regarding the growth of the long bones of rats was conducted. Finally, transcriptomics, proteomics, and bioinformatics were all used to analyze the biological functions and related signaling pathways of the T. tridentatus plasma in order to promote rat bone growth. The results showed that the contents of amino acid residues in peptides are related to the growth promotion that was contained in the 10–30 kDa plasma group. Moreover, the T. tridentatus plasma samples were found to be higher in this respect than those in the whole plasma group. In addition, the 10–30 kDa plasma group could significantly promote bone growth activity in rats. The proteomic analysis showed that the proteins that were differentially expressed in the 10–30 kDa plasma group were mainly enriched in the PI3K-AKT signal pathway. Our study suggested that the T. tridentatus plasma possesses promising potential for the purposes of clinical use, whereby it can serve the role of a growth-promoting agent. Full article

(This article belongs to the Special Issue Proteomic Studies for the Identification and Characterization of Marine Bioactive Molecules)

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14 pages, 2301 KiB

Open AccessArticle

Barbamide Displays Affinity for Membrane-Bound Receptors and Impacts Store-Operated Calcium Entry in Mouse Sensory Neurons

by Andrea Hough, Connor Criswell, Asef Faruk, Jane E. Cavanaugh, Benedict J. Kolber and Kevin J. Tidgewell

Mar. Drugs 2023, 21(2), 110; https://doi.org/10.3390/md21020110 - 02 Feb 2023

Viewed by 1803

Abstract

Marine cyanobacteria are a rich source of bio-active metabolites that have been utilized as leads for drug discovery and pharmacological tools for basic science research. Here, we describe the re-isolation of a well-known metabolite, barbamide, from Curaçao on three different occasions and the [...] Read more.

Marine cyanobacteria are a rich source of bio-active metabolites that have been utilized as leads for drug discovery and pharmacological tools for basic science research. Here, we describe the re-isolation of a well-known metabolite, barbamide, from Curaçao on three different occasions and the characterization of barbamide’s biological interactions with targets of the mammalian nervous system. Barbamide was originally discovered as a molluscicidal agent from a filamentous marine cyanobacterium. In our hands, we found little evidence of toxicity against mammalian cell cultures. However, barbamide showed several affinities when screened for binding affinity for a panel of 45 receptors and transporters known to be involved in nociception and sensory neuron activity. We found high levels of binding affinity for the dopamine transporter, the kappa opioid receptor, and the sigma receptors (sigma-1 and sigma-2 also known as transmembrane protein 97; TMEM97). We tested barbamide in vitro in isolated sensory neurons from female mice to explore its functional impact on calcium flux in these cells. Barbamide by itself had no observable impact on calcium flux. However, barbamide enhanced the effect of the TRPV1 agonist capsaicin and enhanced store-operated calcium entry (SOCE) responses after depletion of intracellular calcium. Overall, these results demonstrate the biological potential of barbamide at sensory neurons with implications for future drug development projects surrounding this molecule. Full article

(This article belongs to the Special Issue Bioactive Product from Marine Cyanobacteria)

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14 pages, 2059 KiB

Open AccessArticle

Red Marine Algae Lithothamnion calcareum Supports Dental Enamel Mineralization

by Marcela R. Carrilho and Walter Bretz

Mar. Drugs 2023, 21(2), 109; https://doi.org/10.3390/md21020109 - 02 Feb 2023

Cited by 2 | Viewed by 1905

Abstract

The current management of oral conditions such as dental caries and erosion mostly relies on fluoride-based formulations. Herein, we proposed the use of the remaining skeleton of Lithothamnion calcareum (LC) as an alternative to fluorides. LC is a red macroalgae of the Corallinales [...] Read more.

The current management of oral conditions such as dental caries and erosion mostly relies on fluoride-based formulations. Herein, we proposed the use of the remaining skeleton of Lithothamnion calcareum (LC) as an alternative to fluorides. LC is a red macroalgae of the Corallinales order, occurring in the northeast coast of Brazil, whose unique feature is the abundant presence of calcium carbonates in its cell walls. Two experimental approaches tested the general hypothesis that LC could mediate enamel de-remineralization dynamics as efficiently as fluorides. Firstly, the effect of LC on enamel de-mineralization was determined in vitro by microhardness and gravimetric measurements to test the hypothesis that LC could either prevent calcium/phosphate release from intact enamel or facilitate calcium/phosphate reprecipitation on an artificially demineralized enamel surface. Subsequently, an in situ/ex vivo co-twin control study measured the effect of LC on the remineralization of chemical-demineralized enamel using microhardness and quantitative light-induced fluorescence. With this second experiment, we wanted to test whether outcomes obtained in experiment 1 would be confirmed by an in situ/ex vivo co-twin control model. Both experiments showed that LC exhibited equivalent or superior ability to modulate enamel de-remineralization when compared to fluoride solution. LC should be explored as an alternative to manage oral conditions involving the enamel demineralization. Full article

(This article belongs to the Special Issue Marine Drugs Research in Brazil)

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31 pages, 2385 KiB

Open AccessReview

Diversity and Distribution of Carotenogenic Algae in Europe: A Review

by Konstantin Chekanov

Mar. Drugs 2023, 21(2), 108; https://doi.org/10.3390/md21020108 - 01 Feb 2023

Cited by 15 | Viewed by 5403

Abstract

Microalgae are the richest source of natural carotenoids, which are valuable pigments with a high share of benefits. Often, carotenoid-producing algae inhabit specific biotopes with unfavorable or even extremal conditions. Such biotopes, including alpine snow fields and hypersaline ponds, are widely distributed in [...] Read more.

Microalgae are the richest source of natural carotenoids, which are valuable pigments with a high share of benefits. Often, carotenoid-producing algae inhabit specific biotopes with unfavorable or even extremal conditions. Such biotopes, including alpine snow fields and hypersaline ponds, are widely distributed in Europe. They can serve as a source of new strains for biotechnology. The number of algal species used for obtaining these compounds on an industrial scale is limited. The data on them are poor. Moreover, some of them have been reported in non-English local scientific articles and theses. This review aims to summarize existing data on microalgal species, which are known as potential carotenoid producers in biotechnology. These include Haematococcus and Dunaliella, both well-known to the scientific community, as well as less-elucidated representatives. Their distribution will be covered throughout Europe: from the Greek Mediterranean coast in the south to the snow valleys in Norway in the north, and from the ponds in Amieiro (Portugal) in the west to the saline lakes and mountains in Crimea (Ukraine) in the east. A wide spectrum of algal secondary carotenoids is reviewed: β-carotene, astaxanthin, canthaxanthin, echinenone, adonixanthin, and adonirubin. For convenience, the main concepts of biology of carotenoid-producing algae are briefly explained. Full article

(This article belongs to the Special Issue Microalgal Carotenoids)

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14 pages, 1133 KiB

Open AccessArticle

Neosuberitenone, a New Sesterterpenoid Carbon Skeleton; New Suberitenones; and Bioactivity against Respiratory Syncytial Virus, from the Antarctic Sponge Suberites sp.

by Joe Bracegirdle, Stine S. H. Olsen, Michael N. Teng, Kim C. Tran, Charles D. Amsler, James B. McClintock and Bill J. Baker

Mar. Drugs 2023, 21(2), 107; https://doi.org/10.3390/md21020107 - 01 Feb 2023

Viewed by 2581

Abstract

Respiratory syncytial virus (RSV) is a highly contagious human pathogen that poses a significant threat to children under the age of two, and there is a current need for new small molecule treatments. The Antarctic sponge Suberites sp. is a known source of [...] Read more.

Respiratory syncytial virus (RSV) is a highly contagious human pathogen that poses a significant threat to children under the age of two, and there is a current need for new small molecule treatments. The Antarctic sponge Suberites sp. is a known source of sesterterpenes, and following an NMR-guided fractionation procedure, it was found to produce several previously unreported metabolites. Neosuberitenone (1), with a new carbon scaffold herein termed the ‘neosuberitane’ backbone, six suberitenone derivatives (2–7), an ansellane-type terpenoid (8), and a highly degraded sesterterpene (9), as well as previously reported suberitenones A (10) and B (11), were characterized. The structures of all of the isolated metabolites including absolute configurations are proposed on the basis of NMR, HRESIMS, optical rotation, and XRD data. The biological activities of the metabolites were evaluated in a range of infectious disease assays. Suberitenones A, B, and F (3) were found to be active against RSV, though, along with other Suberites sp. metabolites, they were inactive in bacterial and fungal screens. None of the metabolites were cytotoxic for J774 macrophages or A549 adenocarcinoma cells. The selectivity of suberitenones A, B, and F for RSV among other infectious agents is noteworthy. Full article

(This article belongs to the Special Issue Marine Metabolomics 2023)

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12 pages, 16703 KiB

Open AccessArticle

Effects of Different Nitrogen Concentrations on Co-Production of Fucoxanthin and Fatty Acids in Conticribra weissflogii

by Xiangyu Rui, David Kwame Amenorfenyo, Ke Peng, Haoming Li, Linfei Wang, Xianghu Huang, Changling Li and Feng Li

Mar. Drugs 2023, 21(2), 106; https://doi.org/10.3390/md21020106 - 01 Feb 2023

Cited by 3 | Viewed by 1593

Abstract

Fucoxanthin and fatty acids are active substances that are beneficial to the growth and immunity of humans and aquatic animals. However, relatively few species have been exploited for fucoxanthin and fatty acids in the industry. At the same time, due to its low [...] Read more.

Fucoxanthin and fatty acids are active substances that are beneficial to the growth and immunity of humans and aquatic animals. However, relatively few species have been exploited for fucoxanthin and fatty acids in the industry. At the same time, due to its low extract content, poor stability, high production cost, and serious seasonal and regional limitations, the industry cannot normally meet the greater demand of the international market. Therefore, this experiment seeks to improve the fucoxanthin and fatty acid content of C. weissflogii by adjusting the nitrogen concentration in the culture medium. It was found that when the nitrogen concentration was 150 mg L⁻¹, the cell number was 1.5 × 10⁶ cell mL⁻¹, and the average biomass was 0.75 g L⁻¹. The mean value of carotenoid concentration was 2.179 mg L⁻¹. The average concentration of fucoxanthin was 1.547 mg g⁻¹. When the nitrogen concentration was 75 mg L⁻¹, the fatty acid content reached its highest. By adjusting the concentration of nitrogen, the contents of fucoxanthin and fatty acids were increased. The results provided a theoretical basis for commercial extraction of fucoxanthin and fatty acids and further promoted the industrialization of fucoxanthin and fatty acids. Full article

(This article belongs to the Special Issue Characterization of Bioactive Components in Edible Algae 3rd Edition)

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20 pages, 7586 KiB

Open AccessArticle

Bioactive Peptides from Skipjack Tuna Cardiac Arterial Bulbs (II): Protective Function on UVB-Irradiated HaCaT Cells through Antioxidant and Anti-Apoptotic Mechanisms

by Jing Kong, Xiao-Meng Hu, Wei-Wei Cai, Yu-Mei Wang, Chang-Feng Chi and Bin Wang

Mar. Drugs 2023, 21(2), 105; https://doi.org/10.3390/md21020105 - 01 Feb 2023

Cited by 31 | Viewed by 2318

Abstract

The aim of this study was to investigate the protective function and mechanism of TCP3 (PKK), TCP6 (YEGGD) and TCP9 (GPGLM) from skipjack tuna cardiac arterial bulbs on skin photoaging using UVB-irradiated HaCaT cell model. The present results indicated that TCP3 (PKK), TCP6 [...] Read more.

The aim of this study was to investigate the protective function and mechanism of TCP3 (PKK), TCP6 (YEGGD) and TCP9 (GPGLM) from skipjack tuna cardiac arterial bulbs on skin photoaging using UVB-irradiated HaCaT cell model. The present results indicated that TCP3 (PKK), TCP6 (YEGGD) and TCP9 (GPGLM) had significant cytoprotective effect on UVB-irradiated HaCaT cells (p < 0.001). Hoechst 33342 staining showed that apoptosis of UV-irradiated HaCaT cells could be significantly reduced by the treatment of TCP3 (PKK), TCP6 (YEGGD) and TCP9 (GPGLM); JC-1 staining showed that TCP3 (PKK), TCP6 (YEGGD) and TCP9 (GPGLM) could protect HaCaT cells from apoptosis by restoring mitochondrial membrane potential (MMP); Furthermore, TCP3 (PKK), TCP6 (YEGGD) and TCP9 (GPGLM) could significantly down-regulate the ratio of Bax/Bcl-2 and reduce the expression level of the apoptosis-executing protein Caspase-3 by decreasing the expression of protein Caspase-8 and Caspase-9 (p < 0.05). The action mechanism indicated that TCP3 (PKK), TCP6 (YEGGD) and TCP9 (GPGLM) could up-regulate the expression levels of Nrf2, NQO1 and HO-1 (p < 0.05), which further increased the activity of downstream proteases (SOD, CAT and GSH-Px), and scavenged reactive oxygen species (ROS) and decreased the intracellular levels of malondialdehyde (MDA). In addition, molecular docking indicated that TCP3 (PKK) and TCP6 (YEGGD) could competitively inhibit the Nrf2 binding site because they can occupy the connection site of Nrf2 by binding to the Kelch domain of Keap1 protein. TCP9 (GPGLM) was inferred to be non-competitive inhibition because it could not bind to the active site of the Kelch domain of Keap1 protein. In summary, the antioxidant peptides TCP3 (PKK), TCP6 (YEGGD) and TCP9 (GPGLM) from cardiac arterial bulbs of skipjack tuna can effectively protect HaCaT cells from UVB-irradiated damage and can be used in the development of healthy and cosmetic products to treat diseases caused by UV radiation. Full article

(This article belongs to the Special Issue Marine Bioactive Peptides—Structure, Function, and Application)

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30 pages, 4881 KiB

Open AccessReview

Enzyme Inhibitors from Gorgonians and Soft Corals

by Andrea Córdova-Isaza, Sofía Jiménez-Mármol, Yasel Guerra and Emir Salas-Sarduy

Mar. Drugs 2023, 21(2), 104; https://doi.org/10.3390/md21020104 - 31 Jan 2023

Viewed by 1719

Abstract

For decades, gorgonians and soft corals have been considered promising sources of bioactive compounds, attracting the interest of scientists from different fields. As the most abundant bioactive compounds within these organisms, terpenoids, steroids, and alkaloids have received the highest coverage in the scientific [...] Read more.

For decades, gorgonians and soft corals have been considered promising sources of bioactive compounds, attracting the interest of scientists from different fields. As the most abundant bioactive compounds within these organisms, terpenoids, steroids, and alkaloids have received the highest coverage in the scientific literature. However, enzyme inhibitors, a functional class of bioactive compounds with high potential for industry and biomedicine, have received much less notoriety. Thus, we revised scientific literature (1974–2022) on the field of marine natural products searching for enzyme inhibitors isolated from these taxonomic groups. In this review, we present representative enzyme inhibitors from an enzymological perspective, highlighting, when available, data on specific targets, structures, potencies, mechanisms of inhibition, and physiological roles for these molecules. As most of the characterization studies for the new inhibitors remain incomplete, we also included a methodological section presenting a general strategy to face this goal by accomplishing STRENDA (Standards for Reporting Enzymology Data) project guidelines. Full article

(This article belongs to the Special Issue Enzyme Inhibitors from Marine Resources)

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