P3. Moderate intensity treadmill exercise increases ovulation and modulates genes in the hypothalamus of adult female rats

Rodrigo Marcondes (BR), Thiago Gonçalves (BR), Giulia Araujo (BR), Igor Gomes-Santos (US), Carlos Negrão (BR), Kátia Carvalho (BR), Edmund Baracat (BR), Gustavo Maciel (BR)

[Marcondes] Faculdade de Medicina da Universidade de São Paulo, São Paulo, [Gonçalves] Faculdade de Medicina da Universidade de São Paulo, São Paulo, [Araujo] Faculdade de Medicina da Universidade de São Paulo, São Paulo, [Gomes-Santos] Massachusetts General Hospital / Harvard Medical School, Boston, [Negrão] Faculdade de Medicina da Universidade de São Paulo, São Paulo, [Carvalho] Faculdade de Medicina da Universidade de São Paulo, São Paulo, [Baracat] Faculdade de Medicina da Universidade de São Paulo, São Paulo, [Maciel ] Faculdade de Medicina da Universidade de São Paulo, São Paulo

Context: Exercise is the major challenge to the whole-body homeostasis and induces adaptive responses in many tissues, including reproductive tissues. Lifestyle changes, including exercise, are commonly prescribed to treat some causes of infertility in women. However, the effects of moderate intensity exercise on reproductive parameters are largely unknown. Objective: To investigate the impact of exercise on reproductive tissues and estrous cycle of adult female rats. Methods: At 80 days of age, female rats were randomly sorted into Sedentary controls (Sed; n = 5) or Exercise (Ex; n = 5) groups. Exercise was performed in a treadmill at 60% of VO2peak (moderate intensity) 5 days/week for 6 weeks. Estrous cycle was evaluated. Body weight and food intake were also evaluated. After 6 weeks of exercise, the rats were euthanized and ovaries, uterus, hypothalamus and pituitary were taken. All rats were euthanized during estrus phase. Ovaries and uterus were weighed. Ovarian morphology was evaluated by optical microscopy. Expression of genes related to control of gonadotropin-releasing hormone (GnRH) function in the hypothalamus and pituitary were assessed by qRT-PCR (showed as relative quantification [RQ]). Animals: Female Wistar rats. Interventions: Rats were submitted to treadmill exercise. Main Outcome Measures: Ovarian morphology and expression of genes in hypothalamus and pituitary. Results: Ex rats presented ovaries (29.3 ± 4.4 mg) and uterus (0.823 ± 0.123 g) with higher weight than Sed rats (16.5 ± 1.7 mg and 0.375 ± 0.062 g, respectively) (both p < 0.05). Ovaries from Ex rats presented higher number of corpora lutea compared to controls (33.7 ± 2.9 vs 16.8 ± 2.8 % of total follicles; p < 0.01). Also, there was a tendency to decrease number of atresic follicles (P=0.07) in Ex rats compared to sedentary group. Hypothalamic mRNA expression of Kisspeptin was increased (RQ= 2.98 ± 0.48) and Pro-opiomelanocortin (POMC) (RQ = 0.18 ± 0.003) was decreased in Ex rats compared to Sed (1.0 ± 0.0) (both p < 0.05). There were no differences in estrous cycle, gene expression in the pituitary, body weight and food intake. Conclusions: Exercised showed to increase ovulation in adult female rats, possibly by modulating neuroendocrine factors in the hypothalamus, such as Kisspeptin and POMC. A better knowledge of exercise mechanisms on ovulation might help in the discovering of new targets to develop treatments to infertility.