L-Arginine-Dependent Nitric Oxide Production in the Blood of Patients with Type 2 Diabetes: A Pilot, Five-Year Prospective Study.

: Type 2 diabetes mellitus (T2DM) is a major cardiovascular risk factor. Nitric oxide (NO) is one of the many molecules that regulate vascular tone, and red blood cells (RBCs) are known to play an important role in adjusting cardiac function through NO export from RBCs. Our study prospectively investigated the L-arginine (L-arg)-nitric oxide (NO) metabolic pathway in the erythrocytes and plasma of subjects with T2DM.

L-arginine catabolism is driven mainly towards nitric oxide synthesis in the erythrocytes of patients with type 2 diabetes at first clinical onset.

Background: We investigated the l-arginine (l-Arg)-nitric oxide (NO) metabolic pathway in the erythrocytes (RBCs) and plasma of subjects with type 2 diabetes at first clinical onset.

Methods: RBCs and plasma were collected from 26 patients with type 2 diabetes at first clinical onset and 19 age-matched non-diabetes subjects as controls. l-Arg content was assayed by capillary electrophoresis.

Erythrocyte caspase-3 and antioxidant defense is activated in red blood cells and plasma of type 2 diabetes patients at first clinical onset.

Objectives: We studied erythrocyte (RBC) caspase-3 activity and oxidative status in plasma and RBCs of 33 patients with type 2 diabetes at first clinical onset and 23 age-matched non-diabetes control subjects.

Methods: Caspase-3 activity was assayed during the life span of RBCs; lipid peroxides and total antioxidant capacity (TEAC) were assessed in plasma and RBCs as indicators of oxidative stress and non-enzymatic antioxidant defense; and superoxide dismutase, catalase, and glutathione peroxidase activity were measured in RBCs as enzymatic antioxidants.

Results: We found that, compared to controls, RBCs caspase-3 is activated early in type 2 diabetes (P < 0.