en Nutrition Nutrition پژوهشي Research <span style="font-size:10pt"><span style="unicode-bidi:embed"><span new="" roman="" style="font-family:" times="">Digestion, absorption and metabolism of foods are major functions of intestines as well as liver. Variations in major food components such as carbohydrates, fats and proteins in the diet has been shown to produce negative effects on human health, leading to several diseases. Effects of high carbohydrate diet and high fat diet on various serum parameters and enzymes of brush border membrane, carbohydrate metabolism and oxidative stress in small intestines and livers of rats were assessed. Rats were fed with high carbohydrate diets and/or high fat diets for 28 d. Serum glucose, cholesterol, inorganic phosphate (Pi) and serum alkaline phosphatase increased differentially by high carbohydrate diets and high fat diets. The activity of brush border membrane <a name="_Hlk176637160">enzymes, alkaline phosphatase </a>and sucrose, increased; however, &gamma;-glutamyl transferase decreased by high carbohydrate diet whereas alkaline phosphatase and &gamma;-glutamyl transferase increased; however, sucrase decreased by high fat diet. The activities of metabolic enzymes except lactate dehydrogenase, which was profoundly increased by high carbohydrate diet., significantly decreased by high carbohydrate diet and high fat diet in small intestine. The activity of lactate, malate, glucose-6-phosphate dehydrogenases and NADP-malic enzyme significantly increased; however, glucose-6-phosphatase and fructose-6-phosphatase decreased in the liver by high carbohydrate diets. However, these decreased by high fat diets. The two diets increased oxidative stress as apparent by increased lipid peroxidation with decreased activity of superoxide dismutase and catalase in mucosal and liver homogenates. In conclusion, consumption of <a name="_Hlk177940186">high carbohydrate and fat diets caused extensive alterations in mucosal brush border membrane and liver, disrupted metabolic activity and antioxidant defence mechanism differentially as indicated by the changes in associated enzymes and other parameters. </a></span></span></span> High carbohydrate diets, High fat diets, Intestine, Liver, Brush border membrane, Carbohydrate metabolism, Oxidative stress 47 56 http://nfsr.sbmu.ac.ir/browse.php?a_code=A-10-1142-1&slc_lang=en&sid=1 Neelam Farooq ayusufi@mail.com 10031947532846006897 10031947532846006897 No Aligarh Muslim University Samina Salim ssalim@uh.edu 10031947532846006898 10031947532846006898 No University of Houston Faiz Noor Khan Yusufi fnkyusufi@gmail.com 10031947532846006899 10031947532846006899 No Aligarh Muslim University Faaiza Shahid alisheeba.ali@gmail.com 10031947532846006900 10031947532846006900 No Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, India Sheeba Khan meetsak@rediffmail.com 10031947532846006901 10031947532846006901 No Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, India Sara Anees Khan mkhan268@uic.edu 10031947532846006902 10031947532846006902 No SVKMs Mithibai College, Bhakti Vedanta Swami Marg, Vile Parle (W), Mumbai 400056, India Md Wasim Khan shirinhasan2008@gmail.com 10031947532846006903 10031947532846006903 No Division of Endocrinology, Diabetes & Metabolism, Department of Medicine, University of Illinois, Chicago, IL, USA Shirin Hasan ayusufi@mail.com 10031947532846006904 10031947532846006904 No Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, India Shazia Aman 10031947532846006906 10031947532846006906 No Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, India Ahad Noor Khan Yusufi ayusufi@mail.com 10031947532846006905 0009-0007-4478-2832 Yes Aligarh Muslim University