Poster Topical Area: Vitamins and Minerals
Location: Hall D
Poster Board Number: 515
Objective: Endothelial dysfunction is an important factor in the pathogenesis of diabetes-related vascular complications. In previous studies, we reported that chromium picolinate and histidinate are nutritional supplements widely promoted to exert beneficial metabolic effects in rats with type 2 diabetes/impaired glucose tolerance. However, whether chromium supplementation may prevent endothelial dysfunction in the process of diabetes and underlying mechanisms remains largely unknown. The aim of this study was to investigate the effects of supplemental chromium picolinate (CrPic) and chromium histidinate (CrHis) on several metabolic parameters and expressions of endothelial nuclear factor-kappa B (NF-κB p65), nitric oxide synthase (eNOS), sirtuin 1 (SIRT1), gp91(phox) and p22(phox) proteins of the aortas in type 2 diabetic rats.
Methods: Nondiabetic and diabetic male Wistar rats were either not supplemented or supplemented with CrPic or CrHis via drinking water to consume 8 μg elemental chromium (Cr) per day for 12 weeks. Diabetes was induced by streptozotocin injection (40 mg/kg i.p., for 2 weeks) and maintained by high-fat-diet feeding.
Results: Diabetes was associated with decreases in endothelial eNOS and SIRT1 and increases in endothelial NF-κB, gp91(phox) and p22(phox) protein levels. Both Cr chelates were effective to increase levels of endothelial eNOS and SIRT1 proteins and to decrease levels of endothelial NF-κB, gp91(phox) and p22(phox) protein in diabetic rats. However, responses to these increases and decreases were more notable when Cr was supplemented as CrHis than as CrPic.
Conclusions: Cr prevents diabetes-induced endothelial dysfunction via enhancing eNOS and SIRT1 activities and by reducing inflammation through endothelial NF-κB p65 inhibition. Histidinate form of Cr was superior to picolinate form of Cr in reducing endothelial NF-κB expression and increasing endothelial eNOS and SIRT1 expression in the diabetic rats.
Elazig, Elazig, Turkey