Fig. 2

NMN intervention improves POI rats’ estrous cycle and endocrine function. A) Cytological evaluation of vaginal smears (n = 6 rats per group, day 33–42). B) Representative estrous cycles. C) Analyze the percentage of time spent in each estrous cycle quantitatively (n = 6 rats per group). D) Indicators of serum hormones include estradiol (E2) (1) follicle-stimulating hormone (FSH) (2) and luteinizing hormone (LH) (3) (n = 6 rats per group). The data of C are presented as mean ± standard deviation (SD). *p < 0.05, **p < 0.01, ***p < 0.001. ns: no statistically significant difference