Effect of glycemic control on plasma plant sterol levels and post-heparin diamine oxidase activity in type 1 diabetic patients.

We examined the effect of glycemic control on the plasma plant sterol levels (a measure of cholesterol absorption efficacy) and the plasma post-heparin diamine oxidase (DAO) activity (a measure of intestinal mucosal mass) in type 1 diabetes. The plasma plant sterol levels (mmol/mol of cholesterol) and the DAO activities after 30 U/kg of intravenous heparin were determined in age- and sex-matched three groups (12 type 1 diabetic patients undergoing conventional insulin therapy, ten patients undergoing intensive insulin therapy, and ten normal subjects). All patients continued their indicated insulin regimen for 14 days with a weight-maintaining energy restricted diet. The conventional group showed a significant higher (p < 0.001) level of the fasting plasma glucose (FPG) or the glycated albumin (GA), a higher (P < 0.01) DAO activity (2-fold of the peak level), which was observed 10-30 min after the heparin injection, and a higher (P < 0.01) plasma plant sterol levels (1.5-fold) compared with those in the other two groups, respectively. The DAO activity 30 min after the heparin injection significantly correlated with either the glycated albumin (GA) concentration or the plant sterol levels in all subjects. Furthermore, the acute glycemic control by the changes of insulin regimen from conventional to intensive showed a significant reduction of the DAO activity and plant sterols in the same patients. These results suggest that glycemic control in part relates to the intestinal adaptation to cholesterol absorption efficacy in type 1 diabetes.