Antihyperglycemic effects of 3-O-methyl-D-chiro-inositol and D-chiro-inositol associated with manganese in streptozotocin diabetic rats

The acute effects after administration of 3-O-Methyl-D-Chiro-inositol, D-Ch iro-inositol and manganese, components of the pH 2.0 putative mediator of i nsulin action, on plasma glucose were examined in low dose streptozotocin-t reated rats. 3-O-Methyl-D-Chiro-inositol at a bolus dose of 5 mg/kg decreas ed plasma glucose 6% at 120 min (p < 0.05). A higher bolus dose of 3-O-Meth yl-D-Chiro-inositol (15 mg/kg) promoted a more persistent hypoglycemic effe ct of 22% at 120 min (p < 0.05). Infusion of 8.3 mu g/min of manganese chlo ride lowered plasma glucose by 23% (p < 0.05). 3-O-Methyl-D-Chiro-inositol (15 mg/kg) together with manganese chloride (8.3 mu g/min) promoted a reduc tion of 49% in 120 min (p < 0.05). D-Chiro-inositol at a bolus dose of 5 mg /kg had no effect. A single dose of 15 mg/kg produced a reduction of 21% (p < 0.05) in 120 min. D-Chiro-inositol (15 mg/kg) associated with manganese chloride (8.3 mu g/min) decreased elevated plasma glucose 47% (p < 0.05) in 120 min. D-Chiro-inositol coadministered with manganese reduced glucose co ncentrations during the final 60 min (p < 0.05). 3-O-Methyl-D-Chiro-inosito l and D-chiro-inositol are components of the mediator structure. Manganese is also a presumed component of the mediator, having an important role in g lucose uptake, insulin relase and mediator generation. These compounds have also been identified in the literature as hypogylcemic agents.