Antagonizing Effects of Chromium Against Iron-Decreased Glucose Uptake by Regulating ROS-Mediated PI3K/Akt/GLUT4 Signaling Pathway in C2C12

To investigate the effect of chromium and iron on glucose metabolism via the PI3K/Akt/GLUT4 signaling pathway. Skeletal muscle gene microarray data in T2DM (GSE7014) was selected using Gene Expression Omnibus database. Element-gene interaction datasets of chromium and iron were extracted from comparative toxicogenomics database (CTD). Gene ontology (GO)and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed using DAVID online tool. Cell viability, insulin-stimulated glucose uptake, intracellular reactive oxygen species (ROS) level, and protein expression level were measured in C2C12 cells. The bioinformatics research indicated that PI3K/Akt signaling pathway participated in the effects of chromium and iron associated with T2DM. Insulin-stimulated glucose uptake level was significantly higher in chromium picolinate (Cr group) and lower in ammonium iron citrate (FA group) than that for the control group (P < 0.05); chromium picolinate + ammonium iron citrate (Cr + FA group) glucose uptake level was higher than that for the FA group (P < 0.05). Intracellular ROS level was significantly higher in the FAC group than that for the control group (P < 0.05), and that for the Cr + FA group was lower than that for the FA group (P < 0.05). p-PI3K/PI3K, p-Akt/Akt, and GLUT4 levels were significantly lower in the FA group than that for the control group (P < 0.05), and the Cr + FA group had higher levels than the FA group (P < 0.05). Chromium might have a protective effect on iron-induced glucose metabolism abnormalities through the ROS-mediated PI3K/Akt/GLUT4 signaling pathway.