Neurotrophic Effects of Swimming and Crocin Consumption on the Rats with Obesity Induced by a High-fat Diet

Obesity is known as a multifactorial physical disorder. On the other hand, regular sport exercises and crocin consumption have beneficial effects on obesity. In this regard, the present study aimed to investigate the effect of eight weeks of swimming training with crocin consumption on neurotrophic factors in the heart tissue of obese rats.  In this experimental study, 28 obese Sprague Dawley rats (24 g fat, 24 g protein and 41 g carbohydrates per 100 g) were selected randomly and divided in five groups of seven subjects, including: 1) control (receiving normal saline); (2) swimming training; (3) crocin consumption; and (4) swimming training with crocin consumption. Groups 2 and 4 performed swimming training for eight weeks, three sessions per week, and each session 30-60 minutes, and groups 3 and 4 daily received 25 mg / kg of crocin peritoneally.  Eight weeks of swimming training and swimming training with crocin consumption led to increased expression of BDNF in the heart tissue of obese rats (p≤0.05). Crocin consumption had a significant effect on brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) increase in the heart tissue of obese rats (p ≤0.05). There was no significant difference in BDNF and NGF gene expression levels in the heart tissue of rats in the swimming training with crocin consumption group compared to the crocin consumption group (p ≥0.05).  According to the results, swimming training, swimming training along with crocin consumption, and crocin consumption have the same effects on the increase of BDNF in the heart tissue of obese rats. Also, crocin consumption has a significant effect on increased expression of NGF in the heart tissue of obese rats