Next Article in Journal
Quality Control of Targeted Plasma Lipids in a Large-Scale Cohort Study Using Liquid Chromatography–Tandem Mass Spectrometry
Previous Article in Journal
Optimization of Ultrasonic-Assisted Extraction of α-Glucosidase Inhibitors from Dryopteris crassirhizoma Using Artificial Neural Network and Response Surface Methodology
Previous Article in Special Issue
Metabolomic Strategies to Improve Chemical Information from OSMAC Studies of Endophytic Fungi
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Metabolites
Volume 13
Issue 4
10.3390/metabo13040559
metabolites-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Comparative LC-ESIMS-Based Metabolite Profiling of Senna italica with Senna alexandrina and Evaluating Their Hepatotoxicity

by
Elaheh Zibaee
1,
Maryam Akaberi
2,
Zahra Tayarani-Najaran
3,
Karel Nesměrák
4,
Martin Štícha
5,
Naghmeh Shahraki
6,
Behjat Javadi
1,* and
Seyed Ahmad Emami
1,*
1
Department of Traditional Pharmacy, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad 13131-99137, Iran
2
Department of Pharmacognosy, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad 13131-99137, Iran
3
Targeted Drug Delivery Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad 13131-99137, Iran
4
Department of Analytical Chemistry, Faculty of Science, Charles University, 128 43 Prague, Czech Republic
5
Mass Spectrometry Laboratory, Section of Chemistry, Faculty of Science, Charles University, 128 43 Prague, Czech Republic
6
Medical Toxicology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad 13131-99137, Iran
*
Authors to whom correspondence should be addressed.
Metabolites 2023, 13(4), 559; https://doi.org/10.3390/metabo13040559
Submission received: 7 December 2022 / Revised: 7 January 2023 / Accepted: 7 April 2023 / Published: 13 April 2023
(This article belongs to the Special Issue Metabolomics in Natural Products)
Browse Figures
Review Reports Versions Notes

Abstract

:
Senna Mill. (Fabaceae) is an important medicinal plant distributed worldwide. Senna alexandrina (S. alexandrina), the officinal species of the genus, is one of the most well-known herbal medicines traditionally used to treat constipation and digestive diseases. Senna italica (S. italica), another species of the genus, is native to an area ranging from Africa to the Indian subcontinent, including Iran. In Iran, this plant has been used traditionally as a laxative. However, very little phytochemical information and pharmacological reports investigating its safety of use are available. In the current study, we compared LC-ESIMS metabolite profiles of the methanol extract of S. italica with that of S. alexandrina and measured the content of sennosides A and B as the biomarkers in this genus. By this, we were able to examine the feasibility of using S. italica as a laxative agent like S. alexandrina. In addition, the hepatotoxicity of both species was evaluated against HepG2 cancer cell lines using HPLC-based activity profiling to localize the hepatotoxic components and evaluate their safety of use. Interestingly, the results showed that the phytochemical profiles of the plants were similar but with some differences, particularly in their relative contents. Glycosylated flavonoids, anthraquinones, dianthrones, benzochromenones, and benzophenones constituted the main components in both species. Nevertheless, some differences, particularly in the relative amount of some compounds, were observed. According to the LC-MS results, the amounts of sennoside A in S. alexandrina and S. italica were 1.85 ± 0.095% and 1.00 ± 0.38%, respectively. Moreover, the amounts of sennoside B in S. alexandrina and S. italica were 0.41 ± 0.12 % and 0.32 ± 0.17%, respectively. Furthermore, although both extracts showed significant hepatotoxicity at concentrations of 50 and 100 µg/mL, they were almost non-toxic at lower concentrations. Taken together, according to the results, the metabolite profiles of S. italica and S. alexandrina showed many compounds in common. However, further phytochemical, pharmacological, and clinical studies are necessary to examine the efficacy and safety of S. italica as a laxative agent.

1. Introduction

Senna Mill. is a widespread genus of flowering and perennial plants belonging to the family Fabaceae. This genus has about 282 accepted species distributed worldwide, mostly in tropical and subtropical regions (Table 1) [1,2,3]. Senna alexandrina (S. alexandrina) (Syn. Cassia acutifolia Delile; Cassia alexandrina (Mill.) Spreng.; Cassia senna L.; Senna acutifolia Batka), known as Indian senna, is one of the most well-known herbal medicines in the genus (Figure 1A) [4,5]. In different systems of traditional medicine, S. alexandrina has been mainly used as a laxative to relieve constipation [6,7]. In addition, S. alexandrina has been used traditionally for the treatment of epilepsy, bronchial congestion, typhoid, skin diseases, malaria, intestinal gas, yellow fever, dyspepsia, infections, cholera, and hemorrhoids [8,9,10,11,12,13]. Phytochemically, S. alexandrina comprises mostly anthraquinones (including sennosides A, B, C, and D; rhein; and aloe-emodin), which are potent natural laxatives. The sennosides A and B as senna biomarkers are optic isomers distinguishable on the configuration of the C-10 and C-10’. Moreover, the presence of similar anthraquinones and anthrones has been reported in other species of the genus such as Senna tora [14,15], Senna alata [16,17], and Senna occidentalis [18,19]. However, other phytochemicals including phenolic compounds (isorhamnetin, kaempferol, and kaempferin), glycosides, steroids, and saponins have been isolated from the plants belonging to this genus [10,20,21,22]. Several pharmaceutical activities such as antioxidant [23], anticancer [24], antidiabetic [25], anti-inflammatory [26,27], antimicrobial [28,29], and antihepatoma activity [30] have been reported for S. alexandrina.
Senna italica (S. italica) is native to countries from Africa to the Indian subcontinent, including Iran (Table 1, Figure 1B). In Iran, it is distributed in Hormozgan province and is known as Kowsen [31]. In Hormozgan province, the plant has been used as a laxative and cathartic agent [32]. There are a few studies investigating the specialized metabolites in S. italica. In these studies, compounds such as physcion, chrysophanol, 1,5-dihydroxy-3-methyl anthraquinone, 10,10’-chrysophanol bianthrone, chrysophanol-physcion bianthrone, and chrysophanolisophyscion bianthrone have been reported as the main anthraquinone derivatives in S. italica [33]. Senna italica has shown several pharmaceutical properties such as antioxidant [34], cytotoxicity [35], antibacterial [36,37], antiproliferative [36], hypoglycaemic [38], anti-obesity [38], and anti-inflammatory activities [39,40].
Hepatotoxicity is a major health concern in consuming many medicinal plants. As S. alexandrina is widely used as a laxative agent, some studies have investigated the hepatotoxicity of this valuable herbal medicine. On the basis of the literature review, S. alexandrina has been associated with hepatotoxicity [41]. In addition, the safety of sennosides has been evaluated in a wide range of toxicity experiments. Sennosides have been identified as the hepatotoxin anthraquinone glycosides present in S. alexandrina. Moreover, the overdose of laxatives containing anthraquinone glycosides (sennosides) and the long-term treatment of senna could increase the risk of colon cancer mediated through the overexpression of p53 and p21 [42]. Toyoda et al. reported that the regenerative processes that occurred after inflammatory or cytotoxic changes in response to laxatives (including S. alexandrina), and stimulation would be responsible for inducing cell proliferation. However, sennosides could function as an anti-tumor agent in a low dose. For instance, the administration of sennoside A (10 mg/kg in vivo and 10 μM in vitro) could inhibit the growth of pancreatic cancer cells [43]. To the best of our knowledge, there is no study investigating the hepatotoxicity and safety of S. italica.
In the current study, we aimed to compare the LC-ESIMS and LC-ESIMS/MS metabolite profiles of S. italica with S. alexandrina. By this technique, we were able to evaluate the similarities and differences in their major metabolites. Moreover, the contents of sennosides A and B, as the biomarkers in this genus, were measured in both species. In addition, the hepatotoxicity of S. italica and S. alexandrina were evaluated in an in vitro model of study.

2. Materials and Methods

2.1. Solvents and Chemicals

HPLC-grade solvents were obtained from Merck Millipore (Darmstadt, Germany). For extraction and preparative separation, technical-grade solvents (Mojallali, Iran) were used after distillation. Analytical-grade formic acid (FA), trifluoroacetic acid (TFA), and sulfuric acid were sourced from Merck Millipore (Darmstadt, Germany). DMSO was purchased from Sigma-Aldrich (St. Louis, MO, USA). Deionized water and ultrapure water were prepared using Elix and Milli-Q water purification systems (Merck Millipore, Darmstadt, Germany). Silica gel 60 F254-coated aluminum TLC plates were obtained from Merck (Darmstadt, Germany). AlamarBlue® was purchased from Sigma (Saint Louis, MO, USA); RPMI-1640 and FBS were obtained from Gibco. The analytical standards of sennoside A and sennoside B were purchased from Sigma-Aldrich. Acetic acid (LC-MS purity), methanol (Hypergrade for LC-MS), and sodium acetate (99.995% trace metals basis) were purchased from Sigma-Aldrich.
A liquid chromatograph UHPLC Nexera XR (Shimadzu, Japan) connected with a Compact QTOF Bruker mass spectrometer (Bruker, Germany) using Compass Otofcontrol 4.0 software (Bruker Daltonics, Germany) was used for ESI-MS and ESI-MS/MS analysis of the extracts. Data processing was performed by Compass Data Analysis 4.4 software (Build 200.55.2969) (Bruker Daltonics, Germany). The MS data were collected in negative ionization mode at a scan range of m/z 50–1000. The temperature of the drying gas was 220 °C with a flow rate of 3 dm3/min. The cone voltage was 2800 V.

2.2. Plant Materials

Senna italica aerial parts were collected from Bandar Abbas, Hormozgān Province (Iran), in March 2018. The collected plants were dried at room temperature in the shade and stored in paper bags until extraction. Senna alexandrina was purchased from an herbal store in Mashhad. The plants were identified by botanist Mitra Suzani (Department of Pharmacognosy, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran). Voucher specimens for S. italica (Voucher number 13576) and S. alexandrina have been deposited at the Herbarium of the Faculty of Pharmacy, Mashhad University of Medical Sciences (MUMS), Mashhad, Iran.

2.3. Extraction

To obtain 100% methanol (MeOH) extracts, the dried aerial parts of both plants (100 g) were milled and exhaustively percolated with MeOH (1 L, 24 h) [44]. The extracts were filtered and dried under reduced pressure by a rotary evaporator to afford 16.45 and 13.66 g of solid residue for S. alexandrina (16.45% w/w) and S. italica (13.66% w/w), respectively. To obtain 70% MeOH extracts, 25 g of each plant were percolated with 70% aqueous MeOH for 24 h. The solvents of the obtained extracts were removed by a rotary evaporator to afford 7.65 and 5.36 g of solid residue for S. alexandrina (30.60% w/w) and S. italica (21.44% w/w), respectively. The extracts were stored in a −20 °C freezer until use.

2.4. Microfractionation for Activity Profiling

HPLC-based activity profiling of the samples was performed according to a previously established protocol [44] with some modifications. The microfractionation was performed using a semi-preparative HPLC instrument. Isolation was performed at 22 °C on a HPLC instrument (Knauer, Germany), equipped with a vacuum degasser, Smartline pump 1000, Smartline photodiode-array (PDA) detector 2800 with a UV light source, and a manual injector with a 2 mL sample loop. A Eurospher II 100-5 C18 column (250 mm × 8 mm, 5 μm) (Knauer, Germany) was used for reversed-phase separations, and the chromatograms were obtained at 266 and 340 nm (UVmax of sennosides A and B). Data processing was performed by EZChrome Elite software (Agilent, Germany). The extracts of both plants S. italica and S. alexandrina (100 mg/mL in DMSO) were submitted to HPLC-PDA in four portions of 50 mg (500 μL). The mobile phase was H2O (A) and MeOH (B), both containing 0.05% trifluoroacetic acid (TFA), and the following gradient profile was used: 25% B isocratic (0–1 min), 25% → 65% B (1–30 min), 65% → 100% B (30–31 min), 100% B (31–45 min). The flow rate was 2 mL/min, and 5 min fractions (between min 5 and 45) were collected into test tubes. Corresponding microfractions from the four separations were combined. After drying the plate, microfractions were tested for cytotoxic activity. A sample containing both plant extracts (50 mg/mL) was submitted to HPLC-PDA as a control.

2.5. HPLC-ESI-QqTOFMS and HPLC-ESI-QqTOFMS/MS Analyzes

In order to have a better insight into the metabolic profile of the plants, HPLC-ESIMS analysis of both 70% aqueous and 100% MeOH extracts obtained from S. italica and S. alexandrina was performed. Therefore, using an optimized chromatography condition [45], the compounds in all extracts were separated by LC technique and identified by an ESIMS detector. About 50 mg of the samples were weighed accurately and dissolved in MeOH in a volumetric flask to a final volume of 50.00 mL (i.e., the final concentration was 1 mg/mL). The separation was performed on a column XBridge® BEH C18 (150 × 3.0 mm i.d., particle size 2.5 μm; Waters) at the temperature of 40 °C. The binary mobile phase of MeOH (solvent A) and 0.2% aqueous acetic acid (solvent B) was used with a flow rate of 0.2 mL/min. The following gradient mode was employed: 0.0–17.5 min: 25–65% A, 17.5–18.0 min: 65–80% A, 18.0–20.0 min: 80% A, 20.0–20.5 min: 80–25% A, and 20.5–25.0 min: 25% A. The injected volume was 2 μL. ESI-MS detection was conducted on a Bruker QqTOF compact instrument operated using Compass otofControl 4.0 (Bruker Daltonics, Bremen, Germany) software. Compass DataAnalysis 4.4 (Build 200.55.2969) (Bruker Daltonics, Bremen, Germany) software was used for data processing. ESI-MS data were collected in positive and negative ion modes at a scan range from m/z 50 to m/z 1000. The temperature of the drying gas was set to 220 °C at a 3.0 dm3/min flow rate. The cone voltage was 2800 V.

2.6. Determination of Sennoside A and Sennoside B

Four samples SA1 (S. alexandrina, 100% MeOH extract), SA2 (S. alexandrina, 70% aqueous MeOH extract), SI1 (S. italica, 100% MeOH extract), and SI2 (S. italica, 70% aqueous MeOH extract) were analyzed quantitatively by LC-MS to determine the content of sennosides. Fifty milligrams of each sample was weighed accurately and dissolved in MeOH in a volumetric flask to a final volume of 50.00 mL. The determination was performed according to the procedure published in [45]. Quantification was based on a five-point calibration. Each sample was measured in triplicate. The samples were stored at −18 °C before analysis.

2.7. MZmine Preprocessing

Raw MS data files were converted into mzML files and processed using MZmine 3 [46]. Mass detection was carried out with a centroid mass detector, and a noise level was set for both MS and MS2 levels. The ADAP chromatogram builder parameters including minimum group size of scans, minimum group intensity threshold, minimum highest intensity, and m/z tolerance were set. The wavelets algorithm (XCMS) was used for the chromatogram deconvolution and its settings including S/N threshold, intensity window SN, minimum feature height, coefficient area threshold, peak duration range, and RT wavelet range were optimized. Chromatograms were deisotoped using the isotopic peaks grouper algorithm with an optimized m/z tolerance, RT tolerance, and maximum charge of 2, and the representative isotope used was the most intense. The features were aligned using the join aligner algorithm with an optimized m/z tolerance, weight for m/z, retention time tolerance, and weight for RT. Then, the features were gap-filled using a peak finder algorithm with an optimized intensity tolerance, m/z tolerance, retention time tolerance, and minimum data points. In the end, the data were exported as a CSV file.

2.8. Data Clustering

Data mining resulted in a total of 21 features automatically assembled in a matrix table in Excel. The clustering was performed according to a protocol found anywhere [47,48]. The web application called FreeClust was used for visualizing the features as heatmaps. This application provides an interactive and freely accessible environment for statistical evaluation and data visualization. Initially, all relevant chromatographic and spectroscopic data (retention time and molecular ions with the respective ion abundance) were automatically extracted and assembled in an Excel spreadsheet. The file was then loaded into the online web application FreeClust, and the ESIMS/MS data sets were clustered using sparse hierarchical clustering methods.

2.9. Identification of Compounds

Identification of the metabolites in both Senna species was accomplished by their UV–VIS spectra (220–600 nm); retention times relative to external standards; mass spectra (full scan and tandem MS); and comparison to our in-house database, dictionary of natural products database (CRC), and reference literature.

2.10. Cell Culture

The liver (Hep G2) and B16F10 cancer cell lines were obtained from Pasteur Institute (Tehran, Iran) and maintained in RPMI-1640 medium containing 10% (v/v) fetal bovine serum, 100 U/mL penicillin, and 100 μg/mL streptomycin at 37 °C in a humidified atmosphere of 5% CO2 and 95% air.

2.11. Cell Viability

AlamarBlue® assay was performed to assess the toxicity of the extracts against HepG2 and B16F10 cancer cell lines [49]. To screen cell viabilities, both cancer cell lines (1 × 104 cells per well) were seeded in each well of a 96-well cell-culture plate in a total volume of 100 μL and incubated at 5% CO2 at a temperature of 37 °C for 24 h. Stock solutions (50 mg/mL) of the extract samples were prepared in DMSO and diluted (100, 50, 25, 12.5, 6.25, and 3.125 µg/mL) with the culture medium to ensure that the concentration of DMSO was less than 1% in all samples. Then, the cells were treated with the prepared concentrations of the samples and incubated for 48 h. Following this, resazurin reagent (20 μL) was added to each well, and the absorbance was assessed after 4 h of incubation, at 570 nm and 600 nm using an ELISA microplate reader (Awareness, Palm City, FL, USA) (23). The cytotoxicity of the extracts was expressed as IC50, calculated using Prism 5 Software (GraphPad, La Jolla, CA, USA), and presented as mean ± SEM of three independent experiments with three replicates for each concentration of tested extracts. For each study, a control sample remained untreated and received only medium in place of the test materials. Doxorubicin was used as a positive control at a concentration of 10 µg/mL. The cytotoxicity of the microfractions was also carried out according to the above-mentioned procedure, except that their cytotoxicity was evaluated only at concentrations of 50 and 100 µg/mL.

3. Results

3.1. Cytotoxicity

To evaluate the safety of S. italica and S. alexandrina, the cytotoxic activity of the 100% MeOH fractions was examined against HepG2 cells. Figure 2 shows the cell viability pattern in HepG2 cells after treatment with 100% MeOH extracts of S. alexandrina and S. italica in different concentrations (100–3.1 µg/mL). While both extracts showed significant cytotoxicity at concentrations 100 and 50 µg/mL, they were almost non-toxic at lower concentrations. In addition, the viability pattern for both extracts were similar.
The cytotoxic compounds in the 100% MeOH extracts of S. italica and S. alexandrina were tracked with the aid of HPLC-based activity profiling [44]. An activity profile of eight 5 min fractions and the corresponding LC−UV traces for S. italica and S. alexandrina are shown in Figure 3A,B, respectively. The cytotoxicity of the microfractions was evaluated at a concentration of 50 µg/mL. In general, the microfractions from S. italica were less cytotoxic than those from S. alexandrina. Major cytotoxicity for S. italca was observed for the time window between 25 and 30 min, while for S. alexandrina, the active time window was between 15–20 and 25–30 min (Figure 3).

3.2. HPLC-ESIMS and MS/MS Analysis

3.2.1. Determination of Sennosides A and B

According to the LC-MS results, the amount of sennosides A and B were higher in S. alexandrina than S. italica samples (Table 2).

3.2.2. LC-ESIMS and LC-ESIMS/MS Profiling

Figure 4 and Figure 5 show the LC-MS chromatograms of samples SA1, SA2, SI1, and SI2. As is obvious from Figure 4A,B, the constituents of S. alexandrina and S. italica appeared mostly in retention times between 15 and 20 min. In addition, Figure 5A,B shows that the relative quantity of compounds in 100% MeOH extracts in both plants was higher than that of 70% extracts.
The metabolite profiles of all samples (SA1, SA2, SI1, and SI2) were compared (Figure 6). Interestingly, the 100% and 70% MeOH extracts of S. alexandrina and S. italica were grouped into two distinct clusters. This shows that although some differences were observed for 70% and 100% extracts of each plant species, this difference was not significant. In general, S. alexandrina and S. italica were characterized by a rather similar metabolite pattern and were thus classified into two similar clusters (both in a cluster with blue color). Many of the components were common in both species.

3.2.3. Identification of Compounds

A representative chromatogram (Senna preparation SP2) is presented in Figure 7. Metabolites were identified on the basis of their retention times, UV characteristics, and observed molecular and fragment ions (Table 3 and Table 4). The LC-ESIMS data mining resulted in fifteen components for each plant. The identified metabolites constituted various classes of compounds, including flavonoids, anthraquinones, and acetophenones. However, flavonoid glycosides were the major compounds in both species. Sennosides A (peaks 4 and 6) and B (peaks 10) were detected in both species (Figure 7 and Figure 8). ESIMS− and ESIMS/MS of sennoside A/B are presented in Figure 9. A plausible ESI−-MSn fragmentation of sennoside A/B is illustrated in Figure 10 according to the observed precursor and product ions and literature data [45].
Sennosides A and B, rutin, 2-hydroxyemodin glucoside, and tinnevellin-O-glucoside/torachrysone O-glucoside/isotorachrysone O-glucoside were the common major components in both plant species. Peak 5 in S. alexandrina and peak 8 in S. italica were identified as rutin, which was a major compound in both species. Peaks 11 and 12 were identified as kaempferol-O-hexoside-pentoside and 2-hydroxyemodin glucoside, respectively. While in S. italica, the relative amount of peak 11 was more than S. alexandrina, the relative amount of peak 12 was higher in the latter. Peak 13 in both plants was identified as an O-glucoside derivative of tinnevellin, torachrysone, or isotorachrysone.
According to the results, it seems that flavonoids are more abundant in S. alexandrina. In addition, other classes of compounds such as anthraquinones were detected more in S. italica than S. alexandrina. For instance, whereas anthraquinones such as aloe-emodin and rhein as well as benzochromenones including nrrubrofusarin and toralactone were detected as major compounds in S. italica, they were absent in S. alexandrina.

4. Discussion

In an effort to compare the metabolites of S. italica with S. alexandrina, herein, we presented an LCESI/MS-based approach for metabolite profiling and relative phyto-equivalency evaluation of the two species. A broad spectrum of glycosides was identified. In both species, quercetin, isoquercetin, kaempferol, and rhamnetin/isorhamnetin glycosides were identified as the major flavonoids. Nevertheless, flavonoid derivatives were more abundant in S. alexandrina than S. italica. From the anthraquinone class of compounds, only 2-hydroxyemodin glucoside was detected in S. alexandrina as one of the major compounds, whereas aloe-emodin, rhein, and 2-hydroxyemodin were detected in S. italica. Naphthols including torachrysone/isotorachrysone and their glucoside were detected in both plants. Moreover, both main senna dianthrone glycosides, sennosides A and B, were detected and measured in both plants. According to the literature, the total content of sennosides A and B in dried senna leaflets varies in the range of 1.5–3.0%. Our findings demonstrated that sennosides A and B levels were higher in S. alexandrina than in S. italica. The content of sennoside A in S. alexandrina was nearly double that of S. italica. The amounts of sennoside A in S. alexandrina and S. italica were 1.85 ± 0.095% and 1.00 ± 0.38%, respectively. Moreover, the amounts of sennoside B in S. alexandrina and S. italica were 0.41 ± 0.12% and 0.32 ± 0.17%, respectively. Other sennosides including sennosides C and D were also detected in both species as minor constituents.
Studies show that more than 110 metabolites have been identified from the leaves and pods of S. alexandrina so far. While the reported metabolites mostly belong to flavonoids, viz., kaempferol, other classes of compounds including anthraquinones, bianthrones, and naphthols have been reported. As an example, Farag et al. identified the phytochemical constituents of different samples of S. alexandrina by LC-MS-based metabolomics [50]. They reported that glycosylated flavonoids such as kaempferol glycosides and isorhamnetin glycosides, anthraquinones aloe-emodin, emodin, and rhein (both in free and glycosylated forms); bianthrones sennosides A–D; and naphthols including torachrysone/isotorachrysone and their glycosides constituted the major compounds. Similarly, we observed that glycosylated flavonoids kaempferol, rhamnetin/isorhamnetin, and quercetin; bianthrones sennosieds A and B; and naphthols including torachrysone/isotorachrysone and their glycosides were the major components. However, in opposition to the study of Farag et al., in our study, 2-hyroxyemodin glucoside was the main anthraquinone derivative instead of aloe-emodin, emodin, and rhein. Compared to S. alexandrina, fewer phytochemical studies have been established on S. italica, so less phytochemicals have been reported so far. However, the same category of specialized metabolites including flavonoids, anthraquinones, bianthrones, and naphthols have been reported. For instance, Khalaf et al. isolated and identified physcion, emodin, 2-methoxy-emodin-6-O-β-D-glucopyranoside, tinnevellin, rutin, and 1,6,8-trihydroxy-3-methoxy-9,10-dioxo-9,10-dihydroanthracene from the ethyl acetate and n-butanol fractions of S. italica by NMR technique [55]. Recently, Omer et al. investigated the phenolic profile of S. alexandrina and S. italica by LC-MS profiling [51]. They found that rutin was the major compound in both S. italica (17,285.02 µg/g) and S. alexandrina (6381.85 µg/g). Hyperoside (SI: 1293.52 µg/g, SA: 3299.95 µg/g), quercetin (SI: 1207.88 µg/g), kaempferol-3-glucoside (SI: 1082.75 µg/g, SA: 3299.95 µg/g), isoquercitrin (SI: 1042.35 µg/g, SA: 2752.63 µg/g), and isorhamnetin (SI: 411.96 µg/g, SA: 454.4 µg/g) were the other major flavonoids in the plants. In our study, rutin was similarly one of the major flavonoids in both species. After that, while quercetin/isoquercetin, kaempferol, and rhamnetin/isorhamnetin were the main flavonoid derivatives in S. alexandrina, kaempferol and rhamnetin/isorhamnetin dominated in S. italica.
Senna alexandrina appears to have been medically used as a purgative to treat constipation since the ninth or tenth century. The anthraquinone derivatives particularly dianthrone glycosides in senna are responsible for the laxative effect [56,57,58]. Senna dianthrone glycosides, also known as sennosides, are medications commonly used to treat constipation and empty the large intestine before surgery [56,58]. In 2020, sennoside glycosides were the 291st most commonly prescribed drug in the United States under several brand names. The chief sennosides in senna are sennoside A and sennoside B. Sennoside A and B are optic isomers distinguishable on the configuration of the C-10 and C-10’ [45].
Like S. alexandrina, S. italica has been used as a laxative agent in folk and traditional medicine, particularly in Asian and African countries [59]. According to the literature and our findings, the chemical composition of S. italica is similar to that of S. alexandrina. However, the contents of dianthrones sennosides A and B in S. italica were less than S. alexandrina. Nevertheless, the number of identified anthraquinones in S. italica was higher than that of S. alexandrina; while aloe-emodin, rhein, and 2-hydroxyemodin glucosides were detected in S. italica as the major anthraquinones, only 2-hydroxyemodin glucoside was identified in S. alexandrina as the main anthraquinone derivative.
Studies show that sennosides are responsible for the laxative effects of senna. Mechanistically, sennosides act on and irritate the lining of the intestine wall, thereby causing increased intestinal muscle contractions leading to vigorous bowel movement. Sennoside A and B are metabolized into the active metabolite rhein anthrone by gut bacteria. Then, this metabolite can increase cyclooxegenase 2 (COX2) expression in macrophage cells, leading to an increase in prostaglandin E2 (PGE2). The increase in PGE2 can decrease the expression of aquaporin 3 (AQP3) in mucosal epithelial cells of the large intestine. The laxative effect is produced via the decrease in AQP3 expression that restricts water reabsorption by the large intestine, thereby increasing fecal water content. Moreover, rhein anthrone can stimulate peristalsis in the large intestine. In addition, studies show that rhein anthrone can excite submucosal acetylcholinergic neurons, resulting in increased secretion of chloride and prostaglandin. The movement of chloride ions into the large intestine would also help to draw water into the lumen [58,60].
In addition to senna dianthrones, studies show that senna anthraquinones also have laxative effects. As mentioned above, in the current study, the relative amount of anthraquinone derivatives was higher in S. italica than in S. alexandrina. In our study, rhein, aloe-emodin, emodin, and 2-hydroxy emodin glucosides were identified as the dominant anthraquinones in S. italica. In a mice model of study, rhein could improve motor function and colonic electromyography of constipation and reduce AQP3 expression in the colonic mucosa, thereby relieving the symptoms of constipation effectively [61]. Oppositely, Zhang et al. showed that long-term administration of rhein in Sprague-Dawley rats could develop the constipation via SCF/c-kit signaling pathway [62]. In another mice model of study but on emodin, the laxative effect of the compound has been attributed to an increase in AQP3 expression in the colon of mice [63]. Although laxative activities have been reported for senna anthraquinones, the main laxative effect of senna is due to the presence of sennosides [56,57,58].

5. Conclusions

Senna (S. alexandrina) is an important medicinal plant, particularly to treat constipation. Senna alexandrina is native to the Sahara and Sahel, as well as to the Indian subcontinent. Compared to S. alexandrina, S. italica has a wider distribution, from Africa to the Indian subcontinent. If the laxative properties of S. italica are proven, more plant resources can be used to produce plant-derived laxatives. Thus, the first step is evaluation of the phytochemical profile of S. italica. Our finding suggests that S. italica might be used as a laxative agent because it has a similar metabolite to S. alexandrina. However, since sennosides A and B are the main active constituents responsible for the laxative action of senna, S. italica might be used as a laxative agent with milder effects because it contains less amount of sennosides A and B. In addition, our findings showed that the plants were not cytotoxic at low concentrations. Nevertheless, further studies including pharmacological investigations and clinical trials are needed to evaluate the efficacy and safety of S. italica as a laxative.

Author Contributions

Conceptualization, S.A.E. and M.A.; methodology, E.Z. and M.A.; data gathering, E.Z., K.N, M.Š. and N.S.; software, M.A.; validation, K.N., M.Š. and N.S.; formal analysis, E.Z., Z.T.-N. and M.A.; investigation, E.Z. and M.A.; resources, B.J.; data curation, E.Z., Z.T.-N. and M.A.; writing—original draft preparation, E.Z.; writing—review and editing, S.A.E., B.J. and M.A.; visualization, M.A.; supervision, S.A.E.; project administration, S.A.E.; funding acquisition, B.J. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by Mashhad University of Medical Sciences, grant number 991724.

Institutional Review Board Statement

The study was conducted in accordance with the Declaration of Helsinki, and approved by the Ethics Committee of Mashhad University of Medical Sciences (IR.MUMS.PHARMACY.REC.1400.022, date of approval 2021).

Data Availability Statement

Data is contained within the article.

Acknowledgments

The authors would like to thank Mashhad University of Medical Sciences for help and supports.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Marazzi, B.; Endress, P.K.; De Queiroz, L.P.; Conti, E. Phylogenetic relationships within Senna (Leguminosae, Cassiinae) based on three chloroplast DNA regions: Patterns in the evolution of floral symmetry and extrafloral nectaries. Am. J. Bot. 2006, 93, 288–303. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  2. Rama Reddy, N.R.; Mehta, R.H.; Soni, P.H.; Makasana, J.; Gajbhiye, N.A.; Ponnuchamy, M.; Kumar, J. Next generation sequencing and transcriptome analysis predicts biosynthetic pathway of sennosides from Senna (Cassia angustifolia Vahl.), a non-model plant with potent laxative properties. PLoS ONE 2015, 10, e0129422. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  3. Agarkar, S.; Jadge, D. Phytochemical and pharmacological investigations of genus Cassia: A review. Asian J. Chem. 1999, 11, 295–299. [Google Scholar]
  4. Naz, H.; Nawaz, H.; Hanif, M.A.; Ayub, M.A.; Khatun, S. Indian Senna. In Medicinal Plants of South Asia; Elsevier: Amsterdam, The Netherlands, 2020; pp. 439–449. [Google Scholar]
  5. POWO. Plants of the World Online. 2022. Available online: http://www.plantsoftheworldonline.org/ (accessed on 1 September 2022).
  6. Ramchander, P.J.; Middha, A. Recent advances on senna as a laxative: A comprehensive review. J. Pharmacogn. Phytochem. 2017, 6, 349–353. [Google Scholar]
  7. Leung, L.; Riutta, T.; Kotecha, J.; Rosser, W. Chronic constipation: An evidence-based review. J. Am. Board Fam. Med. 2011, 24, 436–451. [Google Scholar] [CrossRef]
  8. Akbar, S. Senna alexandrina Mill.(Fabaceae/Leguminosae). In Handbook of 200 Medicinal Plants; Springer: Berlin/Heidelberg, Germany, 2020; pp. 1629–1637. [Google Scholar]
  9. Sreejith, G.; Latha, P.G.; Shine, V.J.; Anuja, G.I.; Suja, S.R.; Sini, S.; Shyama, S.; Pradeep, S.; Shikha, P.; Rajasekharan, S. Anti-allergic, anti-inflammatory and anti-lipidperoxidant effects of Cassia occidentalis Linn. Indian J. Exp. Biol. 2010, 48, 494–498. [Google Scholar] [PubMed]
  10. Oladeji, O.S.; Adelowo, F.E.; Oluyori, A.P. The genus Senna (Fabaceae): A review on its traditional uses, botany, phytochemistry, pharmacology and toxicology. S. Afr. J. Bot. 2021, 138, 1–32. [Google Scholar] [CrossRef]
  11. Srivastava, M.; Srivastava, S.; Rawat, A. Chemical standardization of Cassia angustifolia Vahl seed. Pharmacogn. J. 2010, 2, 554–560. [Google Scholar] [CrossRef]
  12. Nkantchoua, G.C.N.; Njapdounke, J.S.K.; Fifen, J.J.; Taiwe, G.S.; Ojong, L.J.; Kandeda, A.K.; Bum, E.N. Anticonvulsant effects of Senna spectabilis on seizures induced by chemicals and maximal electroshock. J. Ethnopharmacol. 2018, 212, 18–28. [Google Scholar] [CrossRef]
  13. Silva, C.; Monteiro, M.; Rocha, H.; Ribeiro, A.; Caldeira-de-Araujo, A.; Leitão, A.; Bezerra, R.; Pádula, M. Assessment of antimutagenic and genotoxic potential of senna (Cassia angustifolia Vahl.) aqueous extract using in vitro assays. Toxicol. In Vitro 2008, 22, 212–218. [Google Scholar] [CrossRef] [PubMed]
  14. Takido, M. Studies on the Constituents of the Seeds of Cassia obtusifolia L.I. The Structure of Obtusifolin. Chem. Pharm. Bull. 1958, 6, 397–400. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  15. Ito, H.; Nishida, Y.; Yamazaki, M.; Nakahara, K.; Michalska-Hartwich, M.; Furmanowa, M.; Leistner, E.; Yoshida, T. Chrysophanol glycosides from callus cultures of monocotyledonous Kniphofia spp. (Asphodelaceae). Chem. Pharm. Bull. 2004, 52, 1262–1264. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  16. Adedayo, O.; Anderson, W.; Moo-Young, M.; Snieckus, V.; Patil, P.; Kolawole, D. Kinetics of antibacterial activity and physicochemical damage caused by the extracts of Senna alata flowers. Pharm. Biol. 2002, 40, 461–465. [Google Scholar] [CrossRef]
  17. Dave, H.; Ledwani, L. A review on anthraquinones isolated from Cassia species and their applications. Indian J. Nat. Prod. Resour. 2012, 3, 291–319. [Google Scholar]
  18. Rai, M. A review on some antidiabetic plants of India. Anc. Sci. Life 1995, 14, 168. [Google Scholar]
  19. Chauhan, D.; Chauhan, J.; Siddiqui, I.; Singh, J. Two new anthraquinone glycosides from the leaves of Cassia occidentalis. Indian J. Chem. 2001, 40B, 860–863. [Google Scholar]
  20. Majid, U.; Siddiqi, T.O.; Aref, I.M.; Iqbal, M. Quantitative changes in proteins, pigments and sennosides of Cassia angustifolia vahl treated with mancozeb. Pak. J. Bot. 2013, 45, 1509–1514. [Google Scholar]
  21. Ayo, R. Phytochemical constituents and bioactivities of the extracts of Cassia nigricans Vahl: A review. J. Med. Plant Res. 2010, 4, 1339–1348. [Google Scholar]
  22. Adelowo, F.; Oladeji, O. An overview of the phytochemical analysis of bioactive compounds in Senna alata. Adv. Biochem. 2017, 5, 102–109. [Google Scholar] [CrossRef] [Green Version]
  23. Laghari, A.Q.; Memon, S.; Nelofar, A.; Laghari, A.H. Extraction, identification and antioxidative properties of the flavonoid-rich fractions from leaves and flowers of Cassia Angustifolia. Am. J. Anal. Chem. 2011, 2, 871. [Google Scholar] [CrossRef] [Green Version]
  24. Ahmed, S.I.; Hayat, M.Q.; Tahir, M.; Mansoor, Q.; Ismail, M.; Keck, K.; Bates, R.B. Pharmacologically active flavonoids from the anticancer, antioxidant and antimicrobial extracts of Cassia angustifolia Vahl. BMC Complement. Altern. Med. 2016, 16, 460. [Google Scholar] [CrossRef] [Green Version]
  25. Jani, D.K.; Goswami, S. Antidiabetic activity of Cassia angustifolia Vahl. and Raphanus sativus Linn. leaf extracts. J. Tradit. Complement. Med. 2020, 10, 124–131. [Google Scholar] [CrossRef] [PubMed]
  26. Cuellar, M.; Giner, R.; Recio, M.; Manez, S.; Rıos, J. Topical anti-inflammatory activity of some Asian medicinal plants used in dermatological disorders. Fitoterapia 2001, 72, 221–229. [Google Scholar] [CrossRef]
  27. Aggarwal, B.; Prasad, S.; Reuter, S.; Kannappan, R.; Yadav, V.; Park, B.; Hye Kim, J.; Gupta, S.; Phromnoi, K.; Sundaram, C. Identification of novel anti-inflammatory agents from Ayurvedic medicine for prevention of chronic diseases:“reverse pharmacology” and “bedside to bench” approach. Curr. Drug Targets 2011, 12, 1595–1653. [Google Scholar] [CrossRef] [Green Version]
  28. VijayaSekhar, V.; Prasad, M.S.; Joshi, D.; Narendra, K.; Satya, A.K.; Rao, K. Assessment of phytochemical evaluation and in-vitro antimicrobial activity of Cassia angustifolia. Int. J. Pharmacogn. Phytochem. Res. 2016, 8, 305–312. [Google Scholar]
  29. Singanboina, K.; Chinna, V.; Kumar Ratnampally, S.; Karnakar Rao, K. Antibacterial activity of Cassia angustifolia (Vahl.) leaf extracts grown in three different soil treatments. Int. J. Pharm. Life Sci. 2014, 5, 3631–3633. [Google Scholar]
  30. Lin, L.T.; Liu, L.T.; Chiang, L.C.; Lin, C.C. In vitro anti-hepatoma activity of fifteen natural medicines from Canada. Phytother. Res. 2002, 16, 440–444. [Google Scholar] [CrossRef] [PubMed]
  31. Safa, O.; Soltanipoor, M.A.; Rastegar, S.; Kazemi, M.; Dehkordi, K.N.; Ghannadi, A. An ethnobotanical survey on hormozgan province, Iran. Avicenna J. Phytomed. 2013, 3, 64. [Google Scholar]
  32. Abdisa, T. Review on traditional medicinal plant and its extract effect on tick control in Ethiopia. J. Vet. Med. Res. 2017, 4, 102. [Google Scholar]
  33. El-Sayed, N.H.; Dooh, A.A.; El-Khrisy, S.; Mabry, T.J. Flavonoids of Cassia Ital. Phytochemistry 1992, 31, 2187. [Google Scholar] [CrossRef]
  34. Jothi, R.S.; Bharathy, V.; Uthayakumari, F. Antioxidant potential of aerial part of Senna italica sub species micrantha Mill. J. Pharm. Sci. Res. 2015, 7, 621. [Google Scholar]
  35. Kuete, V.; Wiench, B.; Alsaid, M.S.; Alyahya, M.A.; Fankam, A.G.; Shahat, A.A.; Efferth, T. Cytotoxicity, mode of action and antibacterial activities of selected Saudi Arabian medicinal plants. BMC Complement. Alternat. Med. 2013, 13, 354. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  36. Masoko, P.; Gololo, S.S.; Mokgotho, M.P.; Eloff, J.N.; Howard, R.; Mampuru, L. Evaluation of the antioxidant, antibacterial, and antiproliferative activities of the acetone extract of the roots of Senna italica (Fabaceae). Afric. J. Tradit. Complement. Altern. Med. 2010, 7, 138–148. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  37. Dabai, Y.; Kawo, A.; Aliyu, R. Phytochemical screening and antibacterial activity of the leaf and root extracts of Senna italica. Afr. J. Pharm. Pharmacol. 2012, 6, 914–918. [Google Scholar] [CrossRef] [Green Version]
  38. Malematja, R.; Bagla, V.; Njanje, I.; Mbazima, V.; Poopedi, K.; Mampuru, L.; Mokgotho, M. Potential hypoglycaemic and antiobesity effects of Senna italica leaf acetone extract. Evid.-Based Complement. Altern. Med. 2018, 2018, 5101656. [Google Scholar] [CrossRef] [Green Version]
  39. Sermakkani, M.; Thangapandian, V. Anti-Inflammatory Potential of Cassia italica (Mill) Lam Leaves. Int. J. Pharm. Pharm. Sci. 2013, 5, 18–22. [Google Scholar]
  40. Jain, S.; Jain, R.; Sharma, R.; Capasso, F. Pharmacological investigation of Cassia italica. J. Ethnopharmacol. 1997, 58, 135–142. [Google Scholar] [CrossRef]
  41. Saravanapriya, P.; Devi, K.P. Plant Extracts with Putative Hepatotoxicity Activity. In Influence of Nutrients, Bioactive Compounds, and Plant Extracts in Liver Diseases; Elsevier: Amsterdam, The Netherlands, 2021; pp. 259–287. [Google Scholar]
  42. van Gorkom, B.A.; Karrenbeld, A.; van der Sluis, T.; Zwart, N.; de Vries, E.G.; Kleibeuker, J.H. Apoptosis induction by sennoside laxatives in man; escape from a protective mechanism during chronic sennoside use. J. Pathol. 2001, 194, 493–499. [Google Scholar] [CrossRef]
  43. Lee, S.Y.; Kim, W.; Lee, Y.G.; Kang, H.J.; Lee, S.H.; Park, S.Y.; Min, J.K.; Lee, S.R.; Chung, S.J. Identification of sennoside A as a novel inhibitor of the Slingshot (SSH) family proteins related to cancer metastasis. Pharmacol. Res. 2017, 119, 422–430. [Google Scholar] [CrossRef]
  44. Akaberi, M.; Danton, O.; Tayarani-Najaran, Z.; Asili, J.; Iranshahi, M.; Emami, S.A.; Hamburger, M. HPLC-based activity profiling for antiprotozoal compounds in the endemic Iranian medicinal plant Helichrysum oocephalum. J. Nat. Prod. 2019, 82, 958–969. [Google Scholar] [CrossRef]
  45. Nesměrák, K.; Kudláček, K.; Čambal, P.; Štícha, M.; Kozlík, P.; Červený, V. Authentication of senna extract from the eighteenth century and study of its composition by HPLC–MS. Mon. Chem. Chem. Mon. 2020, 151, 1241–1248. [Google Scholar] [CrossRef]
  46. Pluskal, T.; Castillo, S.; Villar-Briones, A.; Orešič, M. MZmine 2: Modular framework for processing, visualizing, and analyzing mass spectrometry-based molecular profile data. BMC Bioinform. 2010, 11, 395. [Google Scholar] [CrossRef] [Green Version]
  47. Božičević, A.; Dobrzyński, M.; De Bie, H.; Gafner, F.; Garo, E.; Hamburger, M. Automated comparative metabolite profiling of large LC-ESIMS data sets in an ACD/MS workbook suite add-in, and data clustering on a new open-source web platform FreeClust. Anal. Chem. 2017, 89, 12682–12689. [Google Scholar] [CrossRef] [PubMed]
  48. Akaberi, M.; Najaran, Z.T.; Azizi, N.; Emami, S.A. Metabolite profiling and antiprotozoal activity of three endemic Iranian Helichrysum species. Ind. Crops Prod. 2021, 174, 114196. [Google Scholar] [CrossRef]
  49. Akaberi, M.; Emami, S.A.; Vatani, M.; Tayarani-Najaran, Z. Evaluation of antioxidant and anti-melanogenic activity of different extracts of aerial parts of N. Sintenisii in murine melanoma B16F10 cells. Iran. J. Pharm. Res. 2018, 17, 225–235. [Google Scholar] [PubMed]
  50. Farag, M.A.; El Senousy, A.S.; El-Ahmady, S.H.; Porzel, A.; Wessjohann, L.A. Comparative metabolome-based classification of Senna drugs: A prospect for phyto-equivalency of its different commercial products. Metabolomics 2019, 15, 80. [Google Scholar] [CrossRef]
  51. Omer, H.A.A.; Caprioli, G.; Abouelenein, D.; Mustafa, A.M.; Uba, A.I.; Ak, G.; Ozturk, R.B.; Zengin, G.; Yagi, S. Phenolic Profile, Antioxidant and Enzyme Inhibitory Activities of Leaves from Two Cassia and Two Senna Species. Molecules 2022, 27, 5590. [Google Scholar] [CrossRef]
  52. Coetzee, J.; McIteka, L.; Malan, E.; Ferreira, D. Structure and synthesis of the first procassinidin dimers based on epicatechin, and gallo- and epigallo-catechin. Phytochemistry 2000, 53, 795–804. [Google Scholar] [CrossRef]
  53. Zhou, Z.-h.; Fang, Z.; Jin, H.; Chen, Y.; He, L. Selective Monomethylation of Quercetin. Synthesis 2010, 2010, 3980–3986. [Google Scholar]
  54. Hatano, T.; Uebayashi, H.; Ito, H.; Shiota, S.; Tsuchiya, T.; Yoshida, T. Phenolic constituents of cassia seeds and antibacterial effect of some naphthalenes and anthraquinones on methicillin-resistant Staphylococcus aureus. Chem. Pharm. Bull. 1999, 47, 1121–1127. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  55. Madkour, H.M.; Ghareeb, M.A.; Abdel-Aziz, M.S.; Khalaf, O.M.; Saad, A.M.; El-Ziaty, A.K.; Abdel-Mogib, M. Gas chromatography-mass spectrometry analysis, antimicrobial, anticancer and antioxidant activities of n-hexane and methylene chloride extracts of Senna Ital. J. Appl. Pharm. Sci. 2017, 7, 23–32. [Google Scholar]
  56. Wald, A. Constipation: Advances in Diagnosis and Treatment. JAMA 2016, 315, 185–191. [Google Scholar] [CrossRef] [PubMed]
  57. Kobayashi, M.; Yamaguchi, T.; Odaka, T.; Nakamura, T.; Tsuchiya, S.; Yokosuka, O.; Yano, S. Regionally differential effects of sennoside A on spontaneous contractions of colon in mice. Basic Clin. Pharmacol. Toxicol. 2007, 101, 121–126. [Google Scholar] [CrossRef] [PubMed]
  58. Kon, R.; Ikarashi, N.; Nagoya, C.; Takayama, T.; Kusunoki, Y.; Ishii, M.; Ueda, H.; Ochiai, W.; Machida, Y.; Sugita, K.; et al. Rheinanthrone, a metabolite of sennoside A, triggers macrophage activation to decrease aquaporin-3 expression in the colon, causing the laxative effect of rhubarb extract. J. Ethnopharmacol. 2014, 152, 190–200. [Google Scholar] [CrossRef] [PubMed]
  59. Mncube, S.; Gololo, S.; Mogale, M. Seasonal variations of phytochemical content and antioxidant activity of Senna italica leaves. Asian J. Chem. 2020, 32, 2371–2374. [Google Scholar] [CrossRef]
  60. Le, J.; Ji, H.; Zhou, X.; Wei, X.; Chen, Y.; Fu, Y.; Ma, Y.; Han, Q.; Sun, Y.; Gao, Y.; et al. Pharmacology, Toxicology, and Metabolism of Sennoside A, A Medicinal Plant-Derived Natural Compound. Front. Pharmacol. 2021, 12, 714586. [Google Scholar] [CrossRef] [PubMed]
  61. Sun, L.L.; Jiang, H.B.; Liu, B.Y.; Li, W.D.; Du, A.L.; Luo, X.Q.; Li, X.Q. Effects of rhein on intestinal transmission, colonic electromyography and expression of aquaporin-3 by colonic epithelium cells in constipated mice. Int. J. Clin. Exp. Pathol. 2018, 11, 614–623. [Google Scholar] [PubMed]
  62. Zhang, B.; Huo, M.; Chen, Z.; Gao, F.; Liu, Y.; Zhou, X. Long-Term Administration of Anthraquinone Rhein on Induction of Constipation in Sprague-Dawley Rats via SCF/c-Kit Signaling Pathways. Can. J. Gastroenterol. Hepatol. 2021, 2021, 6649199. [Google Scholar] [CrossRef]
  63. Zheng, Y.F.; Liu, C.F.; Lai, W.F.; Xiang, Q.; Li, Z.F.; Wang, H.; Lin, N. The laxative effect of emodin is attributable to increased aquaporin 3 expression in the colon of mice and HT-29 cells. Fitoterapia 2014, 96, 25–32. [Google Scholar] [CrossRef]
Metabolites 13 00559 g001 550
Figure 1. Senna italica (A) and Senna alexandrina (B) [5].
Figure 1. Senna italica (A) and Senna alexandrina (B) [5].
Metabolites 13 00559 g001
Metabolites 13 00559 g002 550
Figure 2. Viability of HepG2 cells after 48 h treatment with different concentrations (100–3.1 µg/mL) of the methanol extracts of S. italica and S. alexandrina. Doxorubicin (10 µg/mL) and DMSO (1%) were used as positive and negative controls, respectively. Analyses were carried out using the GraphPad Prism V.8 software and the one-way ANOVA test as well as Dunnett’s comparison test. The corresponding p-values marked with an asterisk are as follows: * < 0.05. The data are presented as mean ± SD (n = 3).
Figure 2. Viability of HepG2 cells after 48 h treatment with different concentrations (100–3.1 µg/mL) of the methanol extracts of S. italica and S. alexandrina. Doxorubicin (10 µg/mL) and DMSO (1%) were used as positive and negative controls, respectively. Analyses were carried out using the GraphPad Prism V.8 software and the one-way ANOVA test as well as Dunnett’s comparison test. The corresponding p-values marked with an asterisk are as follows: * < 0.05. The data are presented as mean ± SD (n = 3).
Metabolites 13 00559 g002
Metabolites 13 00559 g003 550
Figure 3. HPLC-based activity profiling of the 100% MeOH extract of (A) Senna italica and (B) Senna alexandrina. The UV chromatograms (266 nm) of separations of 50 mg of extracts on a semipreparative RP-HPLC column are shown. Activity of 5 min microfractions is indicated with colored columns for cytotoxic activity against HepG2 cells, expressed as % cell viability. The cytotoxicity of the microfractions were evaluated at concentration 50 µg/mL.
Figure 3. HPLC-based activity profiling of the 100% MeOH extract of (A) Senna italica and (B) Senna alexandrina. The UV chromatograms (266 nm) of separations of 50 mg of extracts on a semipreparative RP-HPLC column are shown. Activity of 5 min microfractions is indicated with colored columns for cytotoxic activity against HepG2 cells, expressed as % cell viability. The cytotoxicity of the microfractions were evaluated at concentration 50 µg/mL.
Metabolites 13 00559 g003
Metabolites 13 00559 g004 550
Figure 4. LC-MS chromatograms of (A) 100% and (B) 70% MeOH extracts of S. alexandrina (pink) and S. italica (black). For the separation, XBridge® BEH C18 column (150 × 3.0 mm i.d., particle size 2.5 μm; Waters), gradient elution with MeOH and 0.2% aqueous acetic acid with a flow rate 0.2 cm3 min−1 was used. E5: 105, E6: 106. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Figure 4. LC-MS chromatograms of (A) 100% and (B) 70% MeOH extracts of S. alexandrina (pink) and S. italica (black). For the separation, XBridge® BEH C18 column (150 × 3.0 mm i.d., particle size 2.5 μm; Waters), gradient elution with MeOH and 0.2% aqueous acetic acid with a flow rate 0.2 cm3 min−1 was used. E5: 105, E6: 106. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Metabolites 13 00559 g004
Metabolites 13 00559 g005 550
Figure 5. LC-MS chromatograms of 70% (green) and 100% (brown) MeOH extracts of (A) S. alexandrina and (B) S. italica. For the separation, XBridge® BEH C18 column (150 × 3.0 mm i.d., particle size 2.5 μm; Waters), gradient elution with MeOH and 0.2% aqueous acetic acid with a flow rate 0.2 cm3 min−1 were used. E5: 105, E6: 106. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Figure 5. LC-MS chromatograms of 70% (green) and 100% (brown) MeOH extracts of (A) S. alexandrina and (B) S. italica. For the separation, XBridge® BEH C18 column (150 × 3.0 mm i.d., particle size 2.5 μm; Waters), gradient elution with MeOH and 0.2% aqueous acetic acid with a flow rate 0.2 cm3 min−1 were used. E5: 105, E6: 106. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Metabolites 13 00559 g005
Metabolites 13 00559 g006 550
Figure 6. A 2D heat map representing semi-quantitative distribution and metabolite profiling of samples 100% MeOH extract of S. alexandrina (SA1), 100% MeOH extract of S. italica (SI1), 70% MeOH extract of S. alexandrina (SA2), and 70% MeOH extract of S. italica (SI2). Sample identity is displayed on the y-axis (right-hand-side of the heatmap). The importance score of each feature is indicated by asterisks. Bayesian clustering was applied. Features (RT and m/z values) are represented on the x-axis. The color intensity (blue to dark red) refers to compound abundance in each sample. ** p < 0.01, *** p < 0.001. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Figure 6. A 2D heat map representing semi-quantitative distribution and metabolite profiling of samples 100% MeOH extract of S. alexandrina (SA1), 100% MeOH extract of S. italica (SI1), 70% MeOH extract of S. alexandrina (SA2), and 70% MeOH extract of S. italica (SI2). Sample identity is displayed on the y-axis (right-hand-side of the heatmap). The importance score of each feature is indicated by asterisks. Bayesian clustering was applied. Features (RT and m/z values) are represented on the x-axis. The color intensity (blue to dark red) refers to compound abundance in each sample. ** p < 0.01, *** p < 0.001. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Metabolites 13 00559 g006
Metabolites 13 00559 g007 550
Figure 7. HPLC-ESIMS chromatographic profile of S. italica (orange) and S. alexandrina (black) 100% MeOH extracts. ESIMS: base peak chromatogram (BPC), negative ion mode, m/z 150–1500. The compounds were identified by comparing their LC/ESIMS characteristics with literature. Peaks 10s are sennoside A in both samples. Peaks 4 is sennoside B in sample S. alexandrina, and peak 6 in sennoside B in S. italica. E5: 105, E6: 106. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Figure 7. HPLC-ESIMS chromatographic profile of S. italica (orange) and S. alexandrina (black) 100% MeOH extracts. ESIMS: base peak chromatogram (BPC), negative ion mode, m/z 150–1500. The compounds were identified by comparing their LC/ESIMS characteristics with literature. Peaks 10s are sennoside A in both samples. Peaks 4 is sennoside B in sample S. alexandrina, and peak 6 in sennoside B in S. italica. E5: 105, E6: 106. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Metabolites 13 00559 g007
Metabolites 13 00559 g008 550
Figure 8. Extracted ion chromatograms (XICs) of sennosides A and B for S. italica (black) and S. alexandrina (orange) 100% MeOH extracts. ESIMS: extracted ion chromatograms (XIC), negative ion mode, m/z 861.000–862.0000. E5: 105, E6: 106. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Figure 8. Extracted ion chromatograms (XICs) of sennosides A and B for S. italica (black) and S. alexandrina (orange) 100% MeOH extracts. ESIMS: extracted ion chromatograms (XIC), negative ion mode, m/z 861.000–862.0000. E5: 105, E6: 106. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article).
Metabolites 13 00559 g008
Metabolites 13 00559 g009 550
Figure 9. ESI− mass spectra of a sennoside: (A) parent [M-H]− ion of m/z = 861.0721; (B) MS2 spectrum of the ion m/z = 430.0370.
Figure 9. ESI− mass spectra of a sennoside: (A) parent [M-H]− ion of m/z = 861.0721; (B) MS2 spectrum of the ion m/z = 430.0370.
Metabolites 13 00559 g009
Metabolites 13 00559 g010 550
Figure 10. Proposed fragmentation pathway for sennoside A and sennoside B.
Figure 10. Proposed fragmentation pathway for sennoside A and sennoside B.
Metabolites 13 00559 g010
Table
Table 1. The botanical characteristics and distribution of Senna italica and Senna alexandrina [5].
Table 1. The botanical characteristics and distribution of Senna italica and Senna alexandrina [5].
Senna italicaSenna alexandrina
Plantan annual or perennial erect to prostrate herb or subshruba subshrub, shrub, or tree
Distributionseasonally dry tropical biomesubtropical biome
Leaves3–12 cm long, eglandular5–15 cm long, eglandular
Stipulestriangular to ovate-triangular, 3–9 mm longsubulate, linear or narrowly triangular, 3–5 mm long
Leaflets4–6 pairs, obovate-elliptic to obovate-oblong, minutely appressed puberulous4–8 pairs, lanceolate to elliptic, appressed puberulous or pubescent
Racemes2–25 cm long5–30 cm long
Bractsbroadly ovate or elliptic, shortly acuminate, 3–5 mm long, caducouselliptic to obovate, obtuse to shortly acuminate, 5–11 mm long
Sepalsusually blackish or brownish except for hyaline marginsgreenish or hyaline
Petalsyellowish-white to bright yellow, 0.8–2 cm longyellow or orange-yellow, 0.7–1.7 cm long
Stamensarranged, 9–10: 2 anthers large, 4–5 medium-sized, 3 small10: 2 anthers large, 5 medium-sized, 3 small
Podsshortly oblong-falcate, flattened, 3–6 × 1.3–2 cm, transversely venose, with a ridge of raised crests along middle of each valveshortly oblong, slightly curved to almost straight, flattened, dehiscent, transversely septate within
Seedstransversely arranged, compressed, oblong-ovate, apiculate near hilum, often emarginate at opposite end, reticulate, with a small areole on each facetransversely arranged, compressed, oblong or oblong-ovate, apiculate near hilum, often emarginate at opposite end, reticulate or rugose, with a small areole on each face
Native rangeAlgeria, Angola, Botswana, Burkina, Cameroon, Cape Provinces, Cape Verde, Central African Republic, Chad, Djibouti, Egypt, Eritrea, Ethiopia, Free State, Gambia, Gulf States, India, Iran, Iraq, Kenya, KwaZulu-Natal, Lebanon–Syria, Libya, Mali, Mauritania, Morocco, Mozambique, Namibia, Niger, Nigeria, Northern Provinces, Oman, Pakistan, Palestine, Saudi Arabia, Senegal, Sinai, Somalia, Sudan, Swaziland, Tanzania, Uganda, West Himalaya, Western Sahara, Yemen, and ZimbabweAlgeria, Central African Republic, Chad, Djibouti, Egypt, Eritrea, Ethiopia, Gulf of Guinea Island, India, Kenya, Mali, Mauritania, Niger, Nigeria, Oman, Pakistan, Palestine, Saudi Arabia, Sinai, Socotra, Somalia, Sri Lanka, Sudan, and Yemen
Table
Table 2. The amounts of sennosides A and B in 70% and 100% MeOH extracts of S. italica and S. alexandrina. SA1, SA2, SI1, and SI2 refer to S. alexandrina 100%, S. alexandrina 70%, S. italica 100%, and S. italica 70% MeOH extracts, respectively.
Table 2. The amounts of sennosides A and B in 70% and 100% MeOH extracts of S. italica and S. alexandrina. SA1, SA2, SI1, and SI2 refer to S. alexandrina 100%, S. alexandrina 70%, S. italica 100%, and S. italica 70% MeOH extracts, respectively.
SampleContent %
Sennoside A 1Sennoside B
SA11.85 ± 0.0950.41 ± 0.12
SA21.61 ± 0.380.24 ± 0.13
SI11.00 ± 0.380.32 ± 0.17
SI20.61 ± 0.340.18 ± 0.14
1 The sennosides A and B were measured by LC-MS technique using authentic standards.
Table
Table 3. Identification of the compounds in the chromatograms of Senna alexandrina (peak number in Figure 7, retention time in the chromatogram, m/z of [M-H]− ion, molecular formula, identity, and reference to mass spectrum used for confirmation of the substance).
Table 3. Identification of the compounds in the chromatograms of Senna alexandrina (peak number in Figure 7, retention time in the chromatogram, m/z of [M-H]− ion, molecular formula, identity, and reference to mass spectrum used for confirmation of the substance).
Peak No.tr 1 (min)MS−FormulaMS/MSIdentificationRef.
13.52 2149.0249-89.0131Unresolved-
212.01593.0678-503.0483, 473.0416, 383.0238, 353.0172Unresolved-
315.47625.0513C27H30O17300.99381. Quercetin-O-di-hexoside
2. Hydroxykaempferol di-hexoside		[50]
416.61861.0703C42H38O20699.0378, 386.0472, 224.0159, 430.0312Sennoside B[45]
517.17609.0591C27H30O16300.9933Rutin[45,50]
617.32463.0223C21H20O12299.9863, 300.9929Isoquercitrin/hyperoside[51]
717.75609.0586C27H30O16285.0010Kaempferol-O-di-glycoside[45]
818.25639.0654C28H32O17315.0075Isorhamnetin-O-di-hexoside[50]
918.42529.0751C30H26O9289.0320Cassiaflavan-epicatechin[52]
1019.02861.0729C42H38O20430.0303, 386.0474, 224.0176Sennoside A[45]
1119.44593.0671C27H30O15447.0313, 285.0010Kaempferol-O-hexoside-pentoside[45]
1219.65447.0308C21H20O11283.99392-Hydroxyemodin glucoside[50]
1319.86407.0770C20H24O9245.0477Tinnevellin-O-glucoside
Torachrysone/Isotorachrysone O-glucoside		[45,50]
1420.0623.0706C28H32O16315.00701. Rhamnetin/isorhamnetin 3-neohesperidoside
2. Nepetin di-hexoside
3. 2′,3′,4′,6,7-Pentahydroxyflavone di-hexoside		[53]
1524.94245.0484C14H14O4230.0267,
215.0054		Torachrysone/isotorachrysone/tinnevellin[50]
1 Retention time; 2 the common compounds in both species are shown in bold.
Table
Table 4. Identification of the compounds in the chromatograms of Senna italica (peak number in Figure 7, retention time in the chromatogram, m/z of [M–H]− ion, molecular formula, identity, and reference to mass spectrum used for confirmation of the substance).
Table 4. Identification of the compounds in the chromatograms of Senna italica (peak number in Figure 7, retention time in the chromatogram, m/z of [M–H]− ion, molecular formula, identity, and reference to mass spectrum used for confirmation of the substance).
Peak No.tr1 (min)MS−FormulaMS/MSIdentificationRef.
13.52 2149.0249-89.0131Unresolved-
215.16741.0855-299.9895Unresolved-
315.53581.1065C26H30O15563.0961,
257.0457,
239.0385		Norrubrofusarin gentiobioside[54]
415.80487.0218-240.9692Unresolved-
515.85431.0377C21H20O10269.0079
240.0096		Aloe-emodin glucoside[50]
616.61861.0293C42H38O20430.0293, 386.0465, 224.0171Sennoside B[45]
716.96445.0155C21H18O11282.9854, 239.0021Cassic acid (rhein) glucoside[50]
817.17609.0604C27H30O16300.9929Rutin[45,50]
917.75419.0768C20H20O10401.0677, 257.0465, 239.0390De-methyl-toralactone hexoside[54]
1019.02861.0695C42H38O20430.0298, 386.0461, 224.0164Sennoside A[45]
1119.44593.0665C27H30O15447.0316, 285.0000Kaempferol-O-hexoside-pentoside[45]
1219.65447.0301C21H20O11283.99392-Hydroxyemodin glucoside[50]
1319.86407.0768C20H24O9245.0476Tinnevellin-O-glucoside
Torachrysone/Isotorachrysone O-glucoside		[45,50]
1420.0623.0743C28H32O16315.00681. Rhamnetin/isorhamnetin 3-neohesperidoside
2. Nepetin di-hexoside
3. 2’,3’,4’,6,7-Pentahydroxyflavone di-hexoside		[53]
1521.38245.0476C14H14O4230.0260, 215.0048Torachrysone/isotorachrysone/tinnevellin[45,50]
1 Retention time; 2 the common compounds in both species are shown in bold.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Zibaee, E.; Akaberi, M.; Tayarani-Najaran, Z.; Nesměrák, K.; Štícha, M.; Shahraki, N.; Javadi, B.; Emami, S.A. Comparative LC-ESIMS-Based Metabolite Profiling of Senna italica with Senna alexandrina and Evaluating Their Hepatotoxicity. Metabolites 2023, 13, 559. https://doi.org/10.3390/metabo13040559

AMA Style

Zibaee E, Akaberi M, Tayarani-Najaran Z, Nesměrák K, Štícha M, Shahraki N, Javadi B, Emami SA. Comparative LC-ESIMS-Based Metabolite Profiling of Senna italica with Senna alexandrina and Evaluating Their Hepatotoxicity. Metabolites. 2023; 13(4):559. https://doi.org/10.3390/metabo13040559

Chicago/Turabian Style

Zibaee, Elaheh, Maryam Akaberi, Zahra Tayarani-Najaran, Karel Nesměrák, Martin Štícha, Naghmeh Shahraki, Behjat Javadi, and Seyed Ahmad Emami. 2023. "Comparative LC-ESIMS-Based Metabolite Profiling of Senna italica with Senna alexandrina and Evaluating Their Hepatotoxicity" Metabolites 13, no. 4: 559. https://doi.org/10.3390/metabo13040559

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop