Lactobacillus acidophilus LA-5 Ameliorates Inflammation and Alveolar Bone Loss Promoted by A. actinomycetemcomitans and S. gordonii in Mice and Impacts Oral and Gut Microbiomes

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

With interest I’ve read the paper Lactobacillus acidophilus LA-5 ameliorates inflammation and alveolar bone loss promoted by A. actinomycetemcomitans and S. gordonii in mice and impacts oral and gut microbiomes. The authors conducted an animal study in periodontitis model in mice infected with A. actinomycetemcomitans and S. gordonii. Alveolar bone loss, expression of inflammatory mediators and pathogens recognition patterns in the gingiva, as well as the oral and gut microbiomes were assessed in non-infected negative control, positive control (A. actinomycetemcomitans and S. gordonii), probiotic control (Lactobacillus acidophilus) and test group (A. actinomycetemcomitans and S. gordonii + Lactobacillus acidophilus).  The study received the necessary ethical clearance. Also, it is well-planned and well-written. 

Keywords: please, arrange the keywords in the alphabetical order, spell Aggregatibacter actinomycetemcomitans 

 completely, and check if the keywords are MeSH terms.

Introduction

More information is needed on the effects of Lactobacillus-containing probiotics in patients with periodontal disease. There are several systematic reviews on the topic.

Please, add spaces before references in square braces throughout the manuscript.

Please, discuss the possible mechanism explaining the upregulation of Tlr2 and Tlr4 by Lactobacillus acidophilus in mice infected with A. actinomycetemcomitans and S. gordonii (Aa+Sg+LA5) in contrast to mice not infected with these microorganisms (LA5 group).

Please, add directions for further research.

Author Response

Please see the attachment.

Reviewer 2 Report

Comments and Suggestions for Authors

Review.

Journal Microorganisms (ISSN 2076-2607)

Manuscript ID microorganisms-2920597

TypeArticle

Title :Lactobacillus acidophilus LA-5 ameliorates inflammation and alveolar bone loss promoted by A. actinomycetemcomitans and S. gordonii in mice and impacts oral and gut microbiomes.

Authors

Manuela Rocha Bueno * , Fernando Henrique Martins , Catarina Mendes Rocha , Dione Kawamoto , Karin Hitomi Ishikawa , Ellen Sayuri Ando-Suguimoto , Aline Ramos Carlucci , Leticia Sandoli Arroteia , Renato Correa Viana Casarin , Marcia Pinto Alves Mayer

Section

Gut Microbiota

Special Issue

Probiotics, Prebiotics, and Gut Microbes

The conclusion of the article should clearly emphasize that the effectiveness of LA5 is based on in vitro studies with necessary reservations. In fact, the article refers to in vitro research work. Reference: 6 - only suggests a concept. 7- 8- 9-10- 11 are all from in vitro research, 12 - also in vitro and only suggest results. 13- also in vitro with the following comment “The positive regulation of inflammatory factors such as IL-1β promoted by L. acidophilus LA-5 can increase the innate defense antibacterial activity of periodontal tissues. However, this property can be deleterious by increasing the inflammatory response.”

The reference model of the interaction between A. actinomycetemcomitans-S. gordonii (mice), having induced respiratory metabolism is based on studies limited to in vivo experimental abscess model. S. gordonii exhibits synergy with wild-type A. actinomycetemcomitans. The abscess was formed with the strains collected after only 3 days. The authors extrapolate their results to the mouth where a diversity of other Streptococcus species favor periodontal diseases associate with A. actinomycetemcomitans. However, the fact that commensal bacteria promote virulence of pathogens is essentially based on in vitro experimentation. Reservations are necessary before concluding the same results in vivo (humans).

Line 94 : 1984 ref is old  more recent  precision is necessary like  ref 53 and  a new classification can also be mentioned like..

Nørskov-Lauritsen N, Claesson R, Birkeholm Jensen A, Åberg CH, Haubek D. Aggregatibacter Actinomycetemcomitans: Clinical Significance of a Pathobiont Subjected to Ample Changes in Classification and Nomenclature. Pathogens. 2019 Nov 18;8(4):243. doi: 10.3390/pathogens8040243. PMID: 31752205; PMCID: PMC6963667.

 Line 310 : it is necessary to specify for these three references the particular context of these findings (37- use of ATB). 38- diabetes status. 39- review of the literature concerning probiotics in particular). Line 317 : At the end of this paragraph, we must emphasize the need to confirm these various findings through additional investigations.

Line 318 :  this sentence requires a reference (in vivo or in vitro?). Line 320 : instead of pathogens it is better to use the term pathobiont since these bacteria are originally considered as commensals. Line 364: This statement regarding the effectiveness of LA5 must be modulated by the disparity of studies dose, duration and strains of probiotics, animal models, sample sizes, differences from baseline values severity of periodontal disease and follow-up results.

 In addition, tests on a few microorganisms associated with different delivery vehicles

were grouped together in the framework of meta-analyses, thus biasing results.

  Other  recent bibliography  

Probiotic and gingivalis:

·  Duarte C, Al-Yagoob A, Al-Ani A (2019). Efficacy of probiotics used as a periodontal treatment aid: A pilot study. Saudi Dent J. 31(1):143-147.

·   Akram Z, Shafqat SS, Aati Set al. (2020). Clinical efficacy of probiotics in the treatment of gingivitis: A systematic review and meta-analysis. Aust Dent J. 65(1):12-20

Enhance acid resistance of lactobacillus.

·        Qiao Y, Yin B, Zhou W, Wang M, Chang Z, Zhou J, Yue M, Chen J, Liu F, Feng Z. Strategies for enhancing acid resistance of lactobacillus acidophilus through analyzing nutrient consumption patterns. J Sci Food Agric. 2024 Mar 1. doi: 10.1002/jsfa.13424. Epub ahead of print. PMID: 38427028.

Conclusion

No adverse effects of probiotics were reported in a recent systematic review (Ho et al. 2020). However, their use has been associated with a higher risk of infection and/or morbidity (bacteremia and fungemia) in patients who are critically ill, hospitalized, or immunocompromised (Suez et al. 2019). The clinical efficacy, safety, and host modulatory potential of probiotics should be further established through larger-scale, longer clinical trials.

Author Response

Please see the attachment.

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors I thank the authors for their responses and explanations. The article thus corrected with the usual reservations presents the necessary guarantees for publication.v