Efeitos da restrição de caloria, proteínas e aminoácidos de cadeia ramificada no envelhecimento ovariano de camundongos fêmeas

Abstract

Calorie restriction (CR) is a dietary intervention that promote longevity, delays the onset of chronic diseases and preserves the ovarian reserve in females. These effects are attributed to the control of oxidative stress, inflammatory status, cell differentiation, DNA damage and regulation of intracellular pathways such as mTORC1 and FOXO3. However, some studies have observed that the positive impacts of CR can be linked to restriction of protein and branched-chain amino acids (BCAAs) caused by the strategy. The aim of this study was to evaluate the effects of protein and BCAA restriction on primordial follicle activation compared to 30% calorie restriction in mice. For so, 35 female C57BL/6 mice were randomized into 4 groups and treated for 4 months: control group (CTL; n = 8), 30% calorie restriction (CR; n = 9), protein restriction (PR; 15% restriction; n = 9) and BCAA restriction group (BCAAR; 32% restriction of the amino acids leucine, isoleucine and valine; n = 9). Body mass, body composition, food intake, serum levels of BCAAs, glucose metabolism, ovarian reserve and estrous cyclicity were evaluated. We observed that calorie, protein and BCAA restriction prevented mass gain and changed body composition compared to the control. BCAA restriction resulted in increased calorie intake compared to control mice. Interestingly, we observed that calorie and protein restriction prevented activation of primordial follicles and increased the duration of the estrous cycle. No differences were observed for BCAA restriction regarding cyclicity and ovarian reserve. Our data indicates that protein restriction has similar effects to calorie restriction on preservation of ovarian reserve, whereas BCAA restriction alone did not affect it. This occurred despite PR did not reducing calorie intake and CR did not reducing protein intake in levels similar to PR.