Efeitos do treinamento resistido no rim de ratos alimentados com dieta hiperlipídica: aspectos morfológicos, na expressão protéica e nos biomarcadores inflamatórios locais e sistêmicos

Abstract

The prevalence of overweight and obesity increased worldwide in the past decades and are considered major public health problems. Among the many comorbidities associated with these diseases, the kidneys are also a target-organ also affected and in this respect, the physical intervention (recommended as effective against morphophysiological changes) may positively affect this relationship. The aim of the present study was to evaluate the effect of resistance training in rats fed with high-fat diet in protein expression and systemic and local inflammatory biomarkers, and also on histological aspects of renal tissue. 35 male Wistar rats (Rattus norvegicus var albinos, Rodentia, Mammalia) were used and divided into four groups: sedentary (SED; standard diet), sedentary obese [SED-OB; fat diet (30% fat)], trained (RT; standard diet, resistance training) and trained obese [RT-OB; resistance training; fat diet (30% fat)]. After weaning (day 21), animals were randomized into different groups and submitted to the experimental diets for 24 weeks. After 12 weeks of diet, RT and RT-OB groups started the resistance training program for 12 weeks. Training consisted of 4 to 9 climbs (8 to 12 dynamic movements per climb) on a ladder suited with 1.1 meters in height and slope of 80º. Training sessions were carried out with the aid of weights tied to the animal´s tail, with progression weight (50, 75, 90 and 100%) of the maximum predicted load. Every maximum load was increased to the extent that mice could perform the movement with values above 100% in extra climbing. The trainings were performed on mondays, wednesdays and fridays at night cycle of the animals. After the end of the experimental period, the rats were sacrificed and their tissues collected. A high-fat diet was responsible for the weight gain of the animals and induced a lower food intake when compared to those fed with standard chow. The resistance training was effective in gain induction of animal force. Systemically, fat diet induced higher plasma levels of insulin, leptin and MCP-1 in sedentary animals. Locally, this diet increased mTOR and PAI-1, while resistance training seemed effective in phospho-mTOR control. The resistance training was also able to promote histological changes in the kidneys, increasing the area of the glomerulus and renal corpuscle in animals with standard diet.