Oligomannuronate-chromium (III) complex ameliorates insulin resistance in C57BL/KsJ-db/db mice

Diabetes mellitus is the most common metabolic disease and its prevalence is increasing in many countries year by year. More than 90% of diabetes patients are type 2 diabetes, which is caused by insulin resistance and beta-cell dysfunction. In this paper, the oligomannuronate-chromium (III) complex (OM2) was prepared and its effect and mechanism on attenuating insulin resistance in diabetic C57BL/KsJ-db/db mice were studied. The results indicated that oral intake of OM2 (50 mg kg⁻¹d⁻¹) for 42 d decreased blood glucose and lipid concentration, which was associated with the reduced serum insulin concentration and insulin resistance. According to western blot assay, OM2 could activate AMPK pathway to regulate glycogen synthesis, gluconeogenesis and lipid metabolism in the liver, and attenuate the hyperglycemic symptom in db/db mice. The effects of OM2 on attenuating insulin resistance were comparable to that of the established antidiabetic drug metformin, and OM2 showed less adverse effect than metformin in vivo. Based on the effectiveness and low toxicity, OM2 may potentially be used for prevention and treatment of type 2 diabetes mellitus.