الفهرس 
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Abstract
The worldwide epidemic of obesity was a serious threat to public health, in part because the increase in the mass of white adipose tissue (WAT) in obese individuals increases the risk for development of type 2 diabetes mellitus and cardiovascular diseases. The field of nutrigenomics studies the effect of nutrients on health through altering genome, proteome, metabolome, and resulting in physiological changes. For that the present study was conducted to investigate the impact of different dietary components of some appetite related hormones gene expression and their serum protein level in relation with inflammatory adipocytokines, oxidative stress imbalance, blood lipids profile, atherogenic indices and glucose metabolic dysfunction markers in adult male obese albino rats.
Throughout this study a sufficient number of healthy adult male albino rats Sprague-Dawley strain weighing 200 ± 10 g were available for experimentation. All rats were offered the balanced diet with drinking water ad libitum for 7 days for adaptation. A number of 12 animals served as healthy control group fed on balanced diet (group 1). The rest of the 75 animals consumed the high fat- high sucrose diet for 7.5 weeks for induction of obesity until measurement of obesity by body mass index (BMI) [ 0.83±0.046 g/cm2] and Lee index [0.327±0.007 g/cm]. Then the obese rats were divided as following: group (2): Obese control rats fed on the high fat-high sucrose diet, group (3): Obese rats fed on high fiber (20% fiber) as low caloric diet, group (4): Obese rats fed on high antioxidant vitamins (A & E) (782 mg of vitamin A and 2.19 g of vitamin E) and group (5): Obese rats fed on high fiber-high antioxidant vitamins (A & E) mixed diet containing the tested doses. The experimental period was 4 weeks after induction of obesity and the measurements included in this study were nutritional and anthropometrical measures, apparent digestibility measurements, gene expression measurements, in addition of biochemical measurements.
1- The biological data of the study reported that dietary induction of obesity by feeding the high fat-high sucrose diet in rats caused a statistically significant (P<0.05) increment in energy intake, FER, body weight, BMI and Lee index by about 29.4%, 128.6%, 40.9%, 40.7% and 11.6% respectively as compared with the control normal group consumed the balanced diet. However, treatment of obese rats by the mixed high fiber- high antioxidant vitamins (A & E) diet resulted in significant (P<0.05) reduction in energy intake, FER, body weight, BMI and Lee index by about 35.1%, 198.2%, 22.5%, 21.7% and 7.95% respectively as compared with the control obese group. Whereas no significant (P<0.05) changes were observed in food intake and body length of all rat groups.
2- Considering apparent digestibility/fecal characteristics measurements, the high fat-high sucrose diet caused a statistically significant (P<0.05) increase in fecal pH by about 8.1%, with significant decrement in fecal volume by 18.6% as compared with the control normal rats group. Also obesity resulted in a reduction in fecal weight and increase in fecal density which were not significantly (P<0.05) different from their values in the control normal rats group. While treatment of obese rats with high fiber diet resulted in significant (P<0.05) increment in fecal weight and volume by 286.2% and 452.8% with significant (P<0.05) decrement in fecal density and pH by 30.4% and 18.5% respectively as compared with obese control group. Treatment of obese rats with high antioxidant vitamins diet caused similar results. Furthermore, treatment of obese rats with the mixed high fiber- high antioxidant vitamins (A & E) diet resulted in significant (P<0.05) increment in fecal weight and volume by 230.2% and 460.3% respectively accompanied by significant (P<0.05) decrement in fecal density and pH by 41.1% and 18.3% respectively, as compared with obese control group.
3- In studying the potential effect of different dietary components on the gene expression of leptin and adiponectin in adipose tissue, the data presented that induction of obesity resulted in significant (P<0.05) increment in the level of gene expression of leptin hormone in adipose tissue of obese rats by about 57.3%, and significant (P<0.05) reduction in adiponectin gene expression by 35.1% in comparison with the normal control rats fed on the balanced diet. Whereas obese rats treated with the mixed diet containing high fiber- high antioxidant vitamins (A & E) showed a significant (P<0.05) reduction in leptin gene expression in adipose tissue by 27.86% and increase in adiponectin gene expression by 41.84% as compared with obese control group. However, the obese rats fed on the high fiber diet and the obese rats fed on high antioxidant vitamins (A & E) diet didn’t show significant (P<0.05) change in the levels of leptin and adiponectin gene expression in comparison with the control obese group.
4- A significant (P<0.05) reductions in the antioxidant markers GSH blood level and erythrocyte SOD and GPx enzyme activities were observed in the obese rats fed on the HFHS diet by 63.8%, 55.77% and 29.28% respectively as compared with the control normal group. While significant (P<0.05) increase was observed in the pro-oxidative stress markers MDA and NO serum levels by induction of obesity with HFHS diet which recorded 21.41±1.85 µmol/L and 37.19±0.84 µmol/L respectively as compared with control normal group (2.14±0.09 µmol/L and 17.96±0.52 µmol/L respectively). Whereas consumption of high fiber- high antioxidant vitamins (A & E) diet by obese rats resulted in significant (P<0.05) increment in the antioxidants, GSH blood level, and erythrocyte SOD and GPx enzyme activities by 101.2%, 94.02% and 28.81% respectively as compared with the control obese group accompanied by significant (P<0.05) reduction in the pro-oxidant markers, MDA and NO serum levels by 59.7% and 32.2% respectively as compared with the control obese group.
5- from the results it was clear that, induction of obesity resulted in significant (P<0.05) reduction in the anti-inflammatory adipocytokines omentin and vaspin serum levels by 26.9 % and 73.3% respectively with concomitant significant (P<0.05) increase in the pro-inflammatory adipocytokines, TNF-α and IL-6 serum levels by about 229.7% and 345.6% respectively as compared with control normal group. Whereas treatment of obese rats with the mixed diet containing high fiber-high antioxidant vitamins (A & E) caused better and significant (P<0.05) increase in serum omentin and vaspin levels by 20.2% and 180.6% respectively along with significant (P<0.05) reduction in TNF-α and IL-6 serum levels by about 63.7% and 34.3% respectively as compared with obese control group.
6- The results of the study reported that the serum level of leptin hormone was significantly (P<0.05) increased in obese rats fed on the HFHS diet by 129.82% and serum adiponectin hormone level was significantly (P<0.05) reduced by 60.68 % in comparison with the normal group fed on the balanced diet. Whereas obese rats fed on the mixed high fiber- high antioxidant vitamins (A & E) diet showed significant (P<0.05) improvement in the leptin resistance status with significant reduction in serum leptin levels by 30.34% and significant (P<0.05) increment in serum adiponectin levels by 99.09% as compared with the control obese group.
7- With respect to the blood lipids profile and atherogenic indices, obesity resulted in significant (P<0.05) increment in the serum levels of TC, TAGs, VLDL-C and LDL-C by 29.65%, 35.59%, 35.57% and 47.21%, respectively as compared with the normal rat group consuming the balanced diet. This was also reflected on significant increment in the atherogenic indices with increased risk for developing CVDs. While significant (P<0.05) reduction was observed in the serum level of HDL-C in obese rats by 35.79% when compared with the normal rats. Whereas treatment of obese rats with the mixed high fiber- high antioxidant vitamins (A & E) diet resulted in significant (P<0.05) increment in the blood level of HDL-C by 26.76% accompanied by significant (P<0.05) reduction in the serum levels of TC, TAGs, VLDL-C and LDL-C by 20.46%, 21.17%, 21.16% and 26.23% respectively as compared with the control obese group. This was found to be reflected on the values of atherogenic indices which were significantly reduced in the treated groups resulting in reduced risk for CVDs as compared with the obese group.
8- Focusing on the glucose metabolic dysfunction markers blood levels; insulin, HOMA-IR, QUICKI and glucose, HbA1c, it was clear that induction of obesity by feeding the animals on the HFHS diet resulted in significant (P<0.05) increment in the blood levels of insulin, HOMA-IR, glucose and HbA1c by 20.35%, 56.80%, 30.22% and 28.64% respectively as well as significant decrement in the level of QUICK index by 5.26% as compared with the control normal group. However, treatment of obese rats with the mixed high fiber- high antioxidant vitamins (A & E) diet resulted in significant (P<0.05) reduction in the blood levels of insulin, HOMA-IR, glucose and HbA1c by 7.67%, 18.15%, 11.53% and 18.36%, respectively accompanied by significant increment in the level of QUICK index by 2.59% as compared with the control obese group.
In general, the results obtained in this study showed that the different dietary components (high fiber diet and high antioxidant vitamins (A & E) diet) could affect the gene expression of some genes and their protein products level related to obesity. In addition, the low calorie diet and antioxidant vitamins supplemented in diets could improve the state of oxidative stress, inflammation, leptin resistance, lipotoxicity and insulin resistance, which were induced by high calorie diet induced obesity. These results concluded that nutrigenomics can be useful in improvement, treatment and prevention of some public health problems as obesity. Also, the two newly discovered adipokines; omentin and vaspin, can be used as important serum markers of obesity related metabolic dysregulation.