Oral benfotiamine plus α-lipoic acid normalises complication-causing pathways in type 1 diabetes

Aims/hypothesis We determined whether fixed doses of benfotiamine in combination with slow-release alpha-lipoic acid normalise markers of reactive oxygen species-induced pathways of complications in humans. Methods Male participants with and without type 1 diabetes were studied in the General Clinical Research Centre of the Albert Einstein College of Medicine. Glycaemic status was assessed by measuring baseline values of three different indicators of hyperglycaemia. Intracellular AGE formation, hexosamine pathway activity and prostacyclin synthase activity were measured initially, and after 2 and 4 weeks of treatment. Results In the nine participants with type 1 diabetes, treatment had no effect on any of the three indicators used to assess hyperglycaemia. However, treatment with benfotiamine plus alpha-lipoic acid completely normalised increased AGE formation, reduced increased monocyte hexosamine-modified proteins by 40% and normalised the 70% decrease in prostacyclin synthase activity from 1,709 +/- 586 pg/ml 6-keto-prostaglandin F(1 alpha) to 4,696 +/- 533 pg/ml. Conclusions/interpretation These results show that the previously demonstrated beneficial effects of these agents on complication-causing pathways in rodent models of diabetic complications also occur in humans with type 1 diabetes.