Estudo do efeito do inibidor de tripsina purificado de sementes de tamarindo (tamarindus indica l.) em alterações metabólicas e moleculares induzida por dieta em ratos Wistar

Abstract

The increasing prevalence of obesity and all associated noncommunicable chronic diseases (NCDs) has increased the search for new methods to combat them. To investigate the effect of the nutritional pathways of nutritionally unbalanced diets on markers and/or parameters metabolic/biochemical, inflammatory and molecular, and look for molecules that can act by reverse thissituation is essential. In this study, an experimental diet rich in ultraprocessed foods was evaluated and, subsequently, the effect of purified tamarind seed trypsin inhibitor in an experimental model on biochemical and molecular parameters. An experimental diet was produced and its centesimal composition, glycemic index and glycemic load were analyzed. For glycemic index and glycemic load analyzes two groups of Wistar rats were used. It was also evaluated the metabolic changes induced by either this experimental diet and the tamarind seed purified trypsin inhibitor (ITTp). The experiments were conducted in two phases: 1) 17 weeks, in which two groups of Wistar rats (n = 5) were used, one group of animals were fed with the experimental diet, while the other group with the standard diet (Labina®). At the end of this phase, were analyzed: nutritional status, and biochemical, inflammatory, hormonal and molecular parameters and markers. 2) four groups of Wistar rats (n = 5) were used. Of these, three groups of animals were initially fed for 17 weeks with an experimental diet and presented obesity and then two of these groups were treated for 10 days with a) standard diet or b) ITTp (730 µg / kg). The third group of obese Wistar rats received no treatment (negative control) and one more group of eutrophic Wistar rats were added to the experiment as a positive control. On the 11th day of the experiment were evaluated: zoomometric measurements; consumption and weight gain; and biochemical and molecular parameters and markers. The experimental diet showed high glycemic index (77.6) and high glycemic load (38.8). There was a statistically significant difference (p <0.0001) in the cumulative weekly difference in Lee Index values, evidencing an increase in the 17 weeks of study in the group that received the experimental diet. The animals that received the experimental diet presented significantly increased fasting glucose (p = 0.008) when compared to the animals fed by standard diet. There were also statistically significant difference in relation to VLDL-c (p = 0.016) and TG (p = 0.016), being higher in the group of animals that received the experimental diet. Rats from the experimental diet group had significantly higher PPARγ mRNA relative expression in the gonadal and retroperitoneal tissues (p = 0.0121 and p = 0.0024, respectively). The pTTI-treated group showed significantly lower medians than the experimental diet group (p = 0.0065).The group of obese Wistar rats treated with ITTp had the lowest TG and VLDL-c concentrations (p = 0.0108) compared to the other groups. In addition, the group of animals treated with ITTp had significantly lower TNF-α mRNA relative expression (p = 0.025) compared to the other groups, regardless of PPAR-γ mRNA relative expression. This present study presents the ITTp as a bioactive molecule that acts on the modulation of metabolic changes caused by a high glycemic index experimental diet. Therefore, ITTp is a molecule with great biotechnological potential, especially for the development of biopharmaceuticals with anti-TNF-α function.