Insulin secretion in magnesium silicate-induced osteopenia in rats

Local inflammation induced in rats by subcutaneous injection of magnesium silicate is followed by general metabolic, endocrine and immune reactions. Three weeks after inflammation induction, important bone loss, inflammation-mediated osteopenia (IMO) were found. The study proposes to investigate if IMO influences endogenous insulin secretion and if insulin therapy modifies the amount of bone loss, knowing its osteoprotective effect. Experiments were carried out on adult rats, three weeks after local inflammation induction. Baseline glucose and insulin levels did not change as compared to controls. After glucose stimulation, insulinogenic index decreased in the IMO group, which evidences decrease of insulin secretion. Insulin treatment initiated at the same time with IMO did not induce significant changes as regards the response to glucose tolerance test. However, bone calcium was increased as compared to the untreated IMO group, without reaching the control level.