Probiotics ameliorate endocrine disorders via modulating inflammatory pathways: a systematic review

Probiotics has offered a new prospect to treat and manage a variety of endocrine disorders such as obesity, diabetes, non- alcoholic fatty liver disease and metabolic syndrome. The precise mechanisms by which probiotics exert their beneficial effects on endocrine disorders and its associated problems are still indecisive. It seems that regulating the immune system and suppressing pro-inflammatory pathways like tumor necrosis factor-α and interleukin-6 or triggering anti-inflammatory pathways like interleukin-4 and 10 may be one of the potential mechanisms in the managing of endocrine disorders. In this systematic review, we hypothesized that various probiotic strains (Lactobacillus, Biofidiobacteria, Streptococcus, Entrococcus, Clostridium, and Bacillus) alone or in combination with each other could manage endocrine disorders via modulating inflammatory pathways such as suppressing pro-inflammatory cytokines (IL-6, IL-12, TNF-α, TNF-β, NFκB, and MCP-1), stimulating anti-inflammatory cytokines (IL-4,IL-6, IL-22, IL-23, IL-33, and TGF-β) and maintaining other factors like C-reactive protein, Toll like receptors, LPS, and NK cells. Data source this search was performed in PubMed and Scopus. Both human and animal studies were included. Among more than 15,000 papers, 25 studies were identified as eligible for more assessments. Quality assessment of the studies was cheeked by two researchers independently by title and abstract screening, then article which have inclusion criteria were included, and data retrieved from the included full text studies as the authors had originally reported. Results specified that Lactobacillus has been the most widely used probiotic as well as which one exhibiting the extend of the therapeutic effects on endocrine disorders, especially obesity by modulating immune responses. Also, most studies have revealed that probiotics through suppressing pro-inflammatory pathways specially via reducing levels TNF-α cytokine exhibited protective or beneficial effects on endocrine diseases particularly obesity as well as through decreasing level of IL-6 induced therapeutic effects in diabetes. This systematic review suggests that probiotics could ameliorate endocrine disorders via their immunomodulatory effects.