Circulating levels of nitrated apolipoprotein A-I are increased in type 2 diabetic patients

• Published in: Clinical chemistry and laboratory medicine Vol. 43; no. 6; pp. 601 - 606
• Main Authors: Hermo, Ricardo, Mier, Cristina, Mazzotta, Mary, Tsuji, Masatomi, Kimura, Satoshi, Gugliucci, Alejandro
• Format: Journal Article
• Language: English
• Published: Berlin Walter de Gruyter 01.01.2005; New York, NY De Gruyter
• Subjects: Aged; Apolipoprotein A-I - blood; Apolipoprotein A-I - metabolism; Arteriosclerosis - etiology; Arteriosclerosis - metabolism; Biological and medical sciences; Biomarkers - blood; Case-Control Studies; diabetes; Diabetes Complications - etiology; Diabetes Complications - metabolism; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - metabolism; Diabetic Angiopathies - etiology; Diabetic Angiopathies - metabolism; Female; General aspects; Glycated Hemoglobin A - analysis; high-density lipoprotein (HDL); Humans; Investigative techniques, diagnostic techniques (general aspects); macroangiopathy; macroangiopathy, myeloperoxidase; Male; Medical sciences; Middle Aged; myeloperoxidase; Nitrates - blood; Nitrates - metabolism; nitrosative stress; peroxynitrite; Endocrinopathy; Human; Immunopathology; Apolipoprotein(a); Enzyme; Autoimmune disease; Apolipoprotein; Stress; Medicine; Peroxidases; Type 1 diabetes; Clinical biology; Peroxidase; diabetes; high-density lipoprotein (HDL); macroangiopathy; myeloperoxidase; nitrosative stress; peroxynitrite; Oxidoreductases; Lipoprotein HDL; Macroangiopathy
• ISSN: 1434-6621; 1437-4331
• DOI: 10.1515/CCLM.2005.104

Recent work has shown that high-density lipoprotein (HDL) isolated from human atherosclerotic lesions and the blood of patients with established coronary artery disease contains elevated levels of 3-nitrotyrosine and 3-chlorotyrosine. A higher nitrotyrosine content in lipoprotein is significantly associated with diminished cholesterol efflux capacity of the lipoprotein. Since accelerated atherogenesis is a key complication of diabetes mellitus, and nitrosative stress has recently been implicated in diabetic pathology, we set out to demonstrate an increase in the circulating levels of nitrated apolipoprotein A (apoA)-I in type 2 diabetic patients and its putative correlation with metabolic biomarkers. In this work we addressed this hypothesis in a case-control study with 30 type 2 diabetic patients and 30 age-matched control subjects. Nitrated apoA-I was 3280±1910 absorbance peak area/apoA-I (g/L) for diabetic patients and 2320±890 for control subjects (p<0.037). This represents a 50% increase in circulating nitrated apoA-I in diabetic patients to age-matched controls. Diabetic patients also showed increases of a similar magnitude in circulating advanced glycation endproducts measured as pentosidine fluorescence (44.16±16.26 vs. 30.84±12.86 AU; p<0.01) and in circulating lipoperoxides (46.0±18.0 vs. 37.2±18.0 nmol/L; p<0.03). No significant correlation was found between nitration of apoA-I and glycosylated hemoglobin or any of the other parameters measured. If proven in subsequent functional and in vivo studies, increased nitrated apoA-I would represent another mechanism by which nitrosative stress participates in diabetic macro-angiopathy.