The influence of alpha-lipoic acid on ovarian follicle growth in induced aging mice

Abstract

The ovary contains follicles at various developmental stages. The present study aimed to investigate the antioxidant efficiency of alpha-lipoic acid (α-LA) on follicle growth in induced aging ovaries. Juvenile female mice (n=24) were allocated into four groups (n=6, each); the control group received distilled water, and the induced aging group (T1) received D-galactose (300 mg/kg). The co-administrated group (T2) was treated with α-LA (300 mg/kg) and D-galactose (100 mg/kg), while the fourth group (T3) was treated with α-LA (100 mg/kg). At the end of treatments (8 weeks), animals were sacrificed, and ovaries were processed for hematoxylin and eosin staining and immunostaining for proliferating cell nuclear antigen (PCNA). PCNA was detectable in oocytes but only in granulosa cells of activated follicles. The D-galactose treatment successfully induced ovarian aging as the proportion of primordial and growing follicles was significantly reduced accompanied by massively increased atretic follicles. Additionally, only numerous PCNA positively stained follicles were recognized. The co-administrated α-LA moderately rescued the characteristics of ovarian aging. Mice treated with α-LA demonstrated a substantial increase in the population of atretic follicles, antral follicles, and PCNA positively stained follicles. There was no change in oocyte size at any follicle growth stage among groups. In conclusion, α-LA moderately rescued the detrimental impacts of induced ovarian aging. For the first time, the expression of PCNA was linked with ovarian aging, where PCNA-staining has been recognized as a valuable tool to evaluate the proliferative activity of the granulosa cells.

Keywords

• alpha-lipoic acid
• induced ovarian aging
• pcna immunoreactivity