Disease ⇒ Polycystic ovary syndrome {40000170}

Shared Reference Notes

• [1.1] 
  - A dysbiotic gut microbiome from women with PCOS or #Bacteroides vulgatus (positively associated with PCOS in antibiotic-treated mice) transplanted into mice induced a PCOS-like phenotype (HA, disrupted estrous cycle, decreased ovulation, ovarian cysts, and a decrease in fertility.) - Higher testosterone levels are linked with changes in the overall composition of the gut microbial community. It is unclear whether testosterone exerts an effect on gut microbes directly and/or indirectly through actions in androgen target tissues.
• [#Bifidobacterium animalis lactis] - A strain of Bifidobacterium lactis given as a 10-week treatment for PCOS in 14 women with the disorder decreased luteinizing hormone and increased intestinal short-chain fatty acids in a new study
• - #Lactobacillus given to letrozole-treated (induces PCOS) rats reduced androgen levels, improved estrous cyclicity, normalized ovarian morphology, as well as increased #Lactobacillus and #Clostridium species and decreased #Prevotella.
• [#Dexterin] - Resistant dextrin when given to women with PCOS and women without the disorder for three months lowered levels of free testosterone, hirsutism, the interval between menstrual cycles, fasting blood glucose, and lipid profile in group with PCOS
• [#High Fat Diet] - #Inulin improve gut dysbiosis, lower testosterone, and increase estradiol levels while improving ovarian morphology and weight gain in mice fed a high-fat diet
• [1.2] 
  - Women with PCOS has a homogenous gut microbiome and an enrichment in Bacteroides vulgatus, along with an increase in genes that encode bile salt hydrolases. - Stool transplantation from women with PCOS or the administration of B. vulgatus by oral gavage induced insulin resistance, a disrupted estrous cycle and ovarian morphology, altered bile acid metabolism, reduced interleukin-22 secretion and infertility and changes in testosterone and luteinizing hormone levels in recipient mice. - Decrease in glycodeoxycholic acid and subsequent decreased IL-22 also documented in women with PCOS. glycodeoxycholic acid induced intestinal group 3 innate lymphoid cell IL-22 secretion through GATA binding protein 3, and IL-22 in turn improved the PCOS phenotype. This finding is consistent with the reduced levels of IL-22 in individuals with PCOS.
• [1.3] 
  - Bacteroidetes was the phylum with the highest relative abundance among all patients, followed by Firmicutes. - Those with visceral obesity had a higher abundance of Prevotella, Megamonas, and Dialister genera, positively correlated with metabolic markers, and lower abundance of Phascolarctobacterium and Neisseria genera, negatively correlated with metabolic markers.
• [1.4] [#Inflamatory bowel disease] [#Akkermansia muciniphila] [#Antibiotic Therapy] 
  - Conditions like inflammatory bowel disease (IBD), #Salmonella typhimurium infection or post-antibiotic reconstitution may not benefit from #Akkermansia supplementation. - using #Akkermansia in patients with endocrine and gynecological disorders—such as polycystic ovary syndrome (PCOS) or #Endometriosis—that have a higher risk of developing IBD, should be critically evaluated. - the gut microbiota of patients suffering from #Parkinson’s Disease or #Multiple Sclerosis exhibits a characteristic signature of #Akkermansia municiphila abundance.
• [1.5] 
  - The enriched bacterial hydroxysteroid deconjugate activity may contribute to the modulation of the interconversion of conjugated forms of estrogens as well as androgenic molecules > play a role in hormonal dysregulation in PCOS.
• - #Bacteroides vulgatus has also been shown to be enriched in the gut microbiota of PCOS patients and induced PCOS-like symptoms in a murine model by altering bile acid metabolism and host immune response
• [#Bacteroides fragilis, #Escherichia coli] - In patients with PCOS, there were enrichment of #Fusobacterium, #Escherichia, and #Bacteroides at the genus level and #Bacteroides fragilis and #Escherichia coli at the species level.
• [#Butyrate, #Short Chain Fatty Acid] - Butylated #Starch could be metabolized by the gut microbiota to produce SCFAs, which could stimulate the peptide-#Tyrosine-#Tyrosine secretion and the hypothalamic-pituitary-ovarian axis to alleviate PCOS.
• - PCOS > reduction of bile acid (#Glycodeoxycholic acid and #Tauroursodeoxycholic acid) and #IL-22 secretion - administration of #Chenodeoxycholic acid could improve PCOS phenotypes in mice experiments.
• - #Fusobacterium has also been observed to be enriched in the oral microbiota of PCOS patients.
• [1.6] 
  - These deconjugated and unbound “active” estrogens enter the bloodstream and subsequently act on #Estrogen receptor alpha (ERα) and #Estrogen receptor beta (ERβ), eliciting downstream activation of intracellular signaling cascades, gene transcription, and epigenetic effects. - When there is a decrease in β-glucuronidase activity due to an imbalance in the GM community (dysbiosis), there is less #Estrogen deconjugation, resulting in lower circulating #Estrogen levels. - increased β-glucuronidase activity can increase #Estrogen levels.
• [1.7] [#Chronic periodontitis, #Periodontal disease] 
  - women with PCOS may be more likely to suffer from periodontal diseases.
• - Women suffering from PCOS had increased levels of #Fusobacterium and decreased levels of #Actinobacteria in their salivary microbiomes

References Notes