ObjectiveBased on the adenosine 5'-monophosphate （AMP）-activated protein kinase/protein kinase B/nuclear factor erythroid 2-related factor 2 （AMPK/Akt/Nrf2） pathway， this study aims to explore the mechanism by which modified Guishenwan improves glucose and lipid metabolism and oxidative stress in polycystic ovary syndrome （PCOS） rats.MethodsA PCOS rat model was established by continuous oral administration of letrozole （1 mg·kg^-1·d^-1） for 21 days. Successfully modeled rats were randomly divided into a model group， a metformin group （0.25 g·kg^-1）， and low-， medium-， and high-dose modified Guishenwan groups （4.01， 8.02， and 16.04 g·kg^-1·d^-1）， with 8 rats in each group. Ten normal rats were assigned to the normal group. The drug groups were given their respective doses， while the normal and model groups were given an equal volume of normal saline. Intervention lasted for 4 weeks. Testosterone （T）， estradiol （E₂）， follicle-stimulating hormone （FSH）， and luteinizing hormone （LH） were measured by enzyme-linked immunosorbent assay （ELISA）， and the LH/FSH ratio was calculated. Fasting blood glucose （FPG）， fasting insulin （FINS）， triglyceride （TG）， and total cholesterol （TC） levels were measured using an automatic biochemical analyzer， and the insulin resistance index （HOMA-IR） and insulin sensitivity index （HOMA-ISI） were calculated. Oral glucose tolerance test （OGTT） and insulin tolerance test （ITT） were conducted. Malondialdehyde （MDA）， advanced glycation end products （AGEs）， and superoxide dismutase （SOD） levels in serum and ovarian tissue were measured using a chemical fluorescence method. Hematoxylin-eosin （HE） staining was used to assess ovarian tissue pathology. Real-time quantitative fluorescent polymerase chain reaction （Real-time PCR） and Western blot were used to measure the expression of AMPK/Akt/Nrf2 pathway-related genes and proteins in ovarian tissue.ResultsCompared with the normal group， the model group exhibited significantly increased levels of T， LH， LH/FSH， FPG， FINS， TG， TC， and HOMA-IR， while FSH， E₂， and HOMA-ISI were significantly decreased （P<0.05， P<0.01）. MDA and AGEs levels were significantly higher in both serum and ovarian tissue， and SOD levels were significantly reduced （P<0.05）. AMPK， Akt， and Nrf2 mRNA and protein expression in ovarian tissue was also significantly reduced （P<0.05）. The OGTT and ITT results showed significantly higher blood glucose levels at each time point （P<0.05， P<0.01）， with impaired glucose and insulin tolerance. Ovarian follicles showed polycystic changes， reduced corpus luteum， and sparse granulosa cell layers. Compared with the model group， the metformin group and the high-dose modified Guishenwan group showed significant decreases in T， LH， LH/FSH， FPG， FINS， TG， TC， and HOMA-IR， while FSH， E₂， and HOMA-ISI were significantly increased （P<0.05， P<0.01）. In the high-dose modified Guishenwan group， MDA and AGEs levels in serum and ovarian tissue were significantly reduced， and SOD levels were significantly increased （P<0.05）. The mRNA and protein expression of AMPK， Akt， and Nrf2 in ovarian tissue was significantly increased （P<0.05）. OGTT and ITT results showed that blood glucose levels in rats decreased significantly at each time point （P<0.05， P<0.01）. No obvious abnormalities were observed in ovarian tissue. Compared with the low-dose modified Guishenwan group， the high-dose group showed significant decreases in T， LH， LH/FSH， FPG， FINS， TG， TC， and HOMA-IR， while FSH， E₂， and HOMA-ISI were significantly increased （P<0.05）. OGTT and ITT results indicated that the high-dose modified Guishenwan group significantly improved glucose and insulin tolerance in rats. No significant abnormalities were observed in ovarian tissue.ConclusionModified Guishenwan effectively improves glucose and lipid metabolism abnormalities and inhibits oxidative stress in PCOS rats， potentially through regulation of the AMPK/Akt/Nrf2 pathway.

polycystic ovary syndrome;modified Guishenwan;oxidative stress;adenosine 5'-monophosphate （AMP）-activated protein kinase （AMPK）;protein kinase B （Akt）;nuclear factor erythroid 2-related factor 2 （Nrf2）