High fat diet administration leads to the mitochondrial dysfunction and selectively alters the expression of class 1 GLUT protein in mice

Metabolic syndrome is an agglomeration of disorders including obesity, diabetes and cardiovascular diseases and characterized as chronic mild inflammation which elevates the circulatory inflammatory markers. This could be due to mitochondrial dysfunction, oxidative stress and hypoxia as a consequence of high fat diet (HFD) intake. The present study focuses on the effects of HFD on lactate and mitochondrial metabolism as well as tissue dependent changes in glucose transporter (GLUT) expression in liver, skeletal muscles and adipose tissue of mouse. Lactate dehydrogenase (LDH) and mitochondrial dysfunction established the link between the occurrences of metabolic stress due to HFD. In this work, it was observed that chronic HFD administration aggravated the metabolic alterations by causing reduced ATP production, imbalanced oxidative stress and altered class 1 GLUTs expression. Chronic HFD significantly reduced (p<0.001) the superoxide dismutase (SOD), catalase (CAT) activities alongside elevated liver injury markers AST and ALT. This in turn causes decreased ATP/ADP ratio, mitochondrial dysfunction and exacerbated LDH levels. This imbalance further led to altered GLUT expression in hepatic cells, adipose tissue and skeletal muscles. HFD significantly (p<0.001) upregulated the GLUT 1 and 3 expressions while significant downregulated (p<0.001) GLUT 2 and 4 expression in liver, skeletal muscles and white adipose tissue. These results revealed the link between class 1 GLUTs, mitochondrial dysfunction and HFD-induced metabolic disorder. It can be concluded that HFD impacts mitochondrial metabolism and reprograms tissue-dependent glucose transporter.