L-lysine supplementation improved glycemic control, decreased protein glycation, and insulin resistance in type 2 diabetic patients

Lysine treatment decreased diabetic complications associated with type 2 diabetes in the rat models of diabetes and in vitro. Herein, in a single-evaluator–blinded, randomized clinical trial, we investigated the effect of L-Lysine (Lys) intervention in type 2 diabetic patients. Two groups of type 2 diabetic patients (15 females and 10 males in each group) who were under treatment with glibenclamide and metformin underwent a short term (3 months), trial. The test group was orally administered with 3 g/day of Lys. Clinical and biochemical parameters of all patients were measured prior to and after the experimental period and were statistically analyzed. Among the serum parameters, FBS, insulin, HOMA-IR, HSP 70, LCAT, PON1, AOPP, and FRAP improved significantly in the test group. A significant decrease in HbA1c and urine glucose accompanying with positive correlations between HbA1c and FBS, fructosamine and both FBS and HbA1c, HOMA with both insulin and FBS, and FBS with urine glucose indicates that Lys prevents diabetes complications. There were no significant changes in the liver and kidney function tests indicating no toxicity of Lys for patients. In conclusion, Lys inhibited protein glycation, improved glycemic control, and increased antioxidant markers in type 2 diabetic patients; thus, it could be suggested for combinatorial therapy of diabetes with oral hypoglycemic agents to protect against vascular risk factors and other diabetic complications.