Impaired L-arginine metabolism marks endothelial dysfunction in CD73-deficient mice.
Mol Cell Biochem 2019;
458:133-142. [PMID:
31093850 PMCID:
PMC6616215 DOI:
10.1007/s11010-019-03537-4]
[Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 04/12/2019] [Indexed: 12/18/2022]
Abstract
Changes in the ecto-5′-nucleotidase activity—an extracellular nucleotide catabolic enzyme may lead to the inflammation and endothelial dysfunction. We investigated the effect of CD73 deletion on the endothelial function and l-arginine metabolism in various age groups of mice. 1-,3-,6-, and 12-month-old, male C57BL/6 J wild type (WT) and C57BL/6 J CD73−/− (CD73−/−) mice were used. Blood samples were used for the analysis of adenine nucleotide concentrations. Serum samples were analyzed for the concentration of amino acids, Interleukin 6 (IL-6), Intercellular Adhesion Molecule 1 (ICAM-1), Vascular Cell Adhesion Molecule 1 (VCAM-1), and endothelial nitric oxide synthase (eNOS) level. Serum and aortic nitrate/nitrite, as well as aortic arginase and NOS activity in endothelial cells (EC) were evaluated. CD73 deletion led to age-dependent increase in IL-6, ICAM-1, and VCAM-1 concentration compared to WT. All CD73−/− mice age groups were characterized by reduced l-Arginine concentration and eNOS level. Significantly lower NOS activity was noticed in EC isolated from CD73−/− mice lungs in comparison to EC isolated from WT lungs. The l-Arginine/ADMA ratio in the CD73−/− decreased in age-dependent manner in comparison to WT. The nitrate/nitrite ratio was reduced in serum and in aortas of 6-month-old CD73−/− mice as compared to WT. The ornithine/arginine and ornithine/citrulline ratios were increased in CD73−/− compared to controls. Blood (erythrocyte) Adenosine-5′-triphosphate and Adenosine-5′-diphosphate levels were reduced in favor to higher blood Adenosine-5′-monophosphate concentration in CD73−/− mice in comparison to WT. The CD73 deletion leads to the development of age-dependent endothelial dysfunction in mice, associated with impaired l-arginine metabolism. CD73 activity seems to protect endothelium.
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