Ichda Chayati^{1, 2,}, Sunarti³, Yustinus Marsono⁴, Mary Astuti⁴

Hyperglycemia and insulin resistance are caused by high fat, fructose, or fat and fructose diet. The aim of this study was to investigate the effect of anthocyanin extract of purple corn (AEPC) on insulin resistance of rats fed high fat and fructose diet (HFFD). Insulin resistance was induced by feeding HFFD for 4 weeks and Wistar male rats were orally supplemented with the following treatments for the next six weeks: pioglitazone 1.35 mg kg^-1 body weight (bw) as a positive control group (PC), AEPC 6 mg kg^-1 bw (LA), AEPC 12.5 mg kg^-1 bw (MA), and AEPC 25 mg kg^-1 bw (HA), or no treatment as a negative control group (NC). A normal control group was fed a normal diet (NLC) for along 10 weeks. Insulin resistance was indicated by Homeostasis Model Assessments for Insulin Resistance (HOMA-IR) scores. The results showed that HFFD feeding increased HOMA-IR score and blood glucose levels, and decreased levels of plasma glucagon-like peptide 1 (GLP1) and pancreatic glucagon-like peptide 1 receptor (GLP1R). Administration of AEPC reduced HOMA-IR scores and blood glucose levels, increased HOMA-β and HOMA-IS scores, plasma GLP1 and pancreatic GLP1R levels, and improved pancreatic morphology. Our finding suggests that AEPC 12.5 mg kg^-1 bw gave the best conditions to improve insulin resistance as well as standard drug administration pioglitazone 1.35 mg kg^-1 bw via GLP1 and GLP1R mechanism.

anthocyanin, purple corn, hyperglycemia, insulin resistance, GLP1, GLP1R