基于PI3K/Akt信号通路探讨麻黄连翘赤小豆汤改善肥胖型多囊卵巢综合征大鼠的机制OA

Objective:To investigate the mechanisms by which Mahuang Lianqiao Chixiaodoutang(MLC)improves obesity-type polycystic ovary syndrome(PCOS)through the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)signaling pathway.Methods:Thirty-six female Sprague-Dawley(SD)rats were randomly divided into a blank control group(Con)and an obesity-type PCOS model preparation group.The model was induced by gavage with letrozole(1 mg·kg-1)combined with a high-fat diet(HFD).After model establishment,the obesity-type PCOS model preparation group was further divided into the model group(Mod,normal saline),metformin group(Met,0.3 g·kg-1),low-dose MLC group(MLC-L,4.3 g·kg-1),medium-dose MLC group(MLC-M,8.6 g·kg-1),and high-dose MLC group(MLC-H,17.2 g·kg-1).Active components of MLC and targets of obesity-type PCOS were screened from databases,a protein-protein interaction(PPI)network was constructed,and gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis was performed.The gut microbiota structure was analyzed based on 16S rRNA sequencing and correlated with network pharmacology pathways.Body weight and estrous cycle were dynamically monitored.Ovarian morphology was observed by hematoxylin-eosin(HE)staining.Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling(TUNEL).Enzyme-linked immunosorbent assay(ELISA)was used to detect levels of follicle-stimulating hormone(FSH),luteinizing hormone(LH),anti-Müllerian hormone(AMH),testosterone(T),and estradiol(E2).Western blot was used to detect the protein expression levels of phosphorylated PI3K/PI3K(p-PI3K/PI3K),phosphorylated Akt/Akt(p-Akt/Akt),B-cell lymphoma-2(Bcl-2),and Bcl-2-associated X protein(Bax).Results:Network pharmacology screening identified 124 active components of MLC and 408 overlapping targets between the herbal formula and the disease.Core targets such as Akt1 and Bcl-2 were revealed.As indicated by 16S rRNA sequencing,the abundances of Lachnospiraceae,Lachnoclostridium,and Dorea were increased in the MLC groups(P＜0.05),while the abundance of Veillonella was decreased(P＜0.05).KEGG correlation analysis integrating network pharmacology and gut microbiota data showed significant enrichment of the PI3K/Akt signaling pathway.Animal experiments showed that,compared with the Mod group,body weight decreased to normal levels in the Met,MLC-M,and MLC-H groups.The estrous cycle became regular.The number of corpora lutea increased and cystic follicles decreased.Serum levels of T,FSH,and LH/FSH were reduced(P＜0.05,P＜0.01),while the E2 level was increased(P＜0.01).Ovarian cell apoptosis was reduced(P＜0.01),and the protein expression levels of p-PI3K/PI3K,p-Akt/Akt,and Bcl-2 in ovarian tissue were significantly increased,whereas Bax protein expression was significantly decreased(P＜0.05,P＜0.01).Conclusion:MLC can regulate gut microbiota structure,effectively improve ovarian pathology in rats with obesity-type PCOS,and inhibit ovarian granulosa cell apoptosis.The mechanism may be associated with upregulation of the PI3K/Akt signaling pathway.