Arachidonic acid-rich ARASCO oil has anti-inflammatory and antidiabetic actions against streptozotocin + high fat diet induced diabetes mellitus in Wistar rats.

OBJECTIVES:The aim of this study was to investigate the effects of arachidonic acid (AA)-rich ARASCO oil on high-fat diet (HFD) + streptozotocin (STZ)-induced diabetes mellitus in male Wistar rats and its possible mechanisms of action. METHODS:Male Wistar rats with HFD + STZ-induced diabetes were employed in the present study. ARASCO oil was administered orally for the first 7 d consecutively, followed by once weekly throughout the study (14 wk). At various time points, blood glucose and body weight and oral glucose tolerance tests were measured. At the end of the study, animals were sacrificed to collect plasma and various organs and stored at -80°C. Plasma insulin, tumor necrosis factor-α, interleukin-6, and lipoxin A4 were measured. Expression of the following genes was determined: nuclear factor-κΒ (NF-κB), cyclooxygenase-2 (COX-2), 12-lipoxygenase (12-LOX) in pancreas and lipocalin 2 (LPCLN2) in adipose tissue. Various antioxidants were measured in the plasma and other tissues. Area under the curve and insulin sensitivity index were assessed by computing homeostatic model of assessment for insulin resistance, quantitative insulin check index, Matsuda, and Belfiore indices. RESULTS:ARASCO oil treatment decreased hyperglycemia, restored insulin sensitivity, suppressed inflammation, enhanced plasma lipoxin A4 levels, and reversed altered antioxidant status to near normal in animals with HFD + STZ-induced diabetes. CONCLUSION:These results suggest that ARASCO, a rich source of AA, can prevent HFD + STZ-induced diabetes in Wistar rats owing to its anti-inflammatory action. It remains to be seen whether ARASCO oil is useful in preventing or postponing the development of type 2 diabetes mellitus in humans.