Kinoanın (Chenopodium quinoa Willd.) Kafeterya Diyetiyle Beslenen Ratlarda Glikoz Homeostazına Etkisi

Abstract

It is emphasized that pseudo-grains, which provide a superior nutritional composition and biochemical content compared to traditional grains, may be beneficial in the management of metabolic control in obesity and related comorbidities. This study aimed to elucidate the possible protective role of quinoa in rats which metabolic defects such as obesity, glucose intolerance and insulin resistance were induced by cafeteria diet. A total of twenty-four male Wistar rats (aged 3 weeks) were randomly allocated into four experimental groups. Rats were fed with one of the following dietary regimens for 15 weeks: Control diet (CON) (n=6), control diet with quinoa (QUI) (n=6), cafeteria diet (CAF) (n=6), cafeteria diet with quinoa (CFQ) (n=6). Food intake and body weight were recorded on a daily basis. At the end of the dietary intervention, an intraperitoneal glucose tolerance test (IPGTT) was performed. Plasma insulin, GLP-1 ve IGF-1 concentrations were quantified. The relative mRNA expression levels of the hepatic IRS1, IRS2, INSR, AKT2 and AMPK genes involved in the insulin signaling pathway were determined with real-time quantitative PCR. Total daily food intake (g/day) was as follows between the groups: QUI>CON>CAF>CFQ (27.18±0.37 g/day, 25.14±0.60 g/day, 22.81±0.41 g/day, 20.93±0.54 g/day, respectively; p<0.0001); while the average daily energy intake (kcal/day) was QUI>CON=CAF>CFQ (106.8±1.18 kcal/day, 99.57±1.37 kcal/day, 96.31±1.28 kcal/day, 88.20±1.17 kcal/day, respectively; p<0.01) after post hoc analyses. CAF group had the highest final body weight and average weekly weight gain whereas QUI group had the lowest (CAF:416.17±18.61 g vs. QUI:339.67±8.73 g, p<0.05; CAF:18.24±1.03 g vs. QUI:13.92±1.07 g, respectively; p<0.05). In binary comparisons between CON, QUI and CFQ groups, the relevant variables did not differ significantly. The total AUC value of the glycemic response in the IPGTT process was CAF>CON>CFQ>QUI, from weakest glucose tolerance to the strongest among groups after post hoc analyses (p<0.0001). The total AUC value of the insulinemic response provided in the IPGTT process was CON>CFQ=CAF>QUI after post hoc analyses (p<0.0001). Plasma GLP-1 concentration was similar between groups (p>0.05); while plasma IGF-1 level was significantly different (p<0.01). It has been determined that the relative gene expression level of IRS1 gene was significantly different between dietary groups and ranged as QUI>CFQ=CON>CAF (2.433±0.189, 1.342±0.083, 1.268±0.120, 0.664±0.070; p<0.0001, respectively) after post hoc analyses. In addition, the relative gene expression level of the AMPK gene was significantly different between dietary groups (CON:0.955±0.072, QUI:1.570±0.062, CAF:0.638±0.073, CFQ: 0.880±0.095; p<0.0001). Relative gene expression levels of IRS2, AKT2 and INSR genes were similar between dietary groups (for each p>0.05). Quinoa, which is considered as a functional food recently may have the potential to allaviate metabolic defects triggered by an obesogenic diet when included in an adequate and balanced dietary pattern.