Eicosatrienoic acid inhibits estradiol synthesis through the CD36/FOXO1/CYP19A1 signaling pathway to improve PCOS in mice.

Polycystic ovary syndrome (PCOS) is a common metabolic and endocrine disorder characterized by abnormal elevation in hormone levels, with currently lacking effective treatment options. N-3 polyunsaturated fatty acids (PUFA) have broad pharmacological activity and play a beneficial role in the development of PCOS. In this study, we observed that n-3 PUFA-eicosatrienoic acid (ETA) improves the estrous cycle and ovarian morphology in dehydroepiandrosterone (DHEA)-induced PCOS mice, particularly serum hormone levels. Additionally, it suppresses the expression of CYP19A1 and E2 synthesis in human granulosa-like tumor cell line (KGN) cells. Further investigation revealed that ETA significantly upregulates the expression of CD36, cAMP, P-PKA, and FOXO1 in KGN cells and mouse ovaries to lower E2 levels. This conclusion was supported by inhibiting CD36 and FOXO1 at both the mouse and cellular levels. Additionally, ETA treatment decreased the expression of ESR1, Kiss1, Gnrh in the hypothalamus, and GnRHR, Lhß, Egr1, Pitx1, Sf1 in the pituitary of PCOS mice. No differences were observed after ETA treatment in the CD36 and FOXO1 inhibitor groups, indicating that ETA improves PCOS mice by regulating the hypothalamic-pituitary axis through E2 synthesis inhibition. In summary, we have elucidated for the first time the mechanism by which CD36 regulates E2 synthesis in ovarian granulosa cells and demonstrated that ETA activates the CD36 receptor to inhibit E2 synthesis through the cAMP/PKA/FOXO1/CYP19A1 signaling pathway, thereby improving hormonal imbalance and treating PCOS. This provides a new strategy for the effective prevention and treatment of PCOS.

Ginsenoside F2-Mediated Intestinal Microbiota and Its Metabolite Propionic Acid Positively Impact the Gut-Skin Axis in Atopic Dermatitis Mice.

Atopic dermatitis (AD) is a complex inflammatory skin disease induced by multiple factors. AD can also cause intestinal inflammation and disorders of the gut microbiota. Ginseng is a kind of edible and medicinal plant; its main active components are ginsenosides. Ginsenosides have a variety of anti-inflammatory effects and regulate the gut microbiota; however, their role in AD and the underlying mechanisms are unclear. In this study, we found that intragastric administration of ginsenoside F2 improved AD-like skin symptoms and reduced inflammatory cell infiltration, serum immunoglobulin E levels, and mRNA expression of inflammatory cytokines in AD mice. 16s rRNA sequencing analysis showed that ginsenoside F2 altered the intestinal microbiota structure and enriched the short-chain fatty acid-producing microbiota in AD mice. Metabolomic analysis revealed that ginsenoside F2 significantly increased the propionic acid (Pa) content of feces and serum in AD mice, which was positively correlated with significant enrichment of Parabacteroides goldsteinii and Lactobacillus plantarum in the intestines. Pa inhibits inflammatory responses in the gut and skin of AD mice through the G-protein-coupled receptor43/NF-κB pathway, thereby improving skin AD symptoms. These results revealed, for the first time, the mechanism by which ginsenoside F2 improves AD through the Pa (a metabolite of intestinal microbiota)-gut-skin axis.