Severe dyslipidaemia, atherosclerosis, and sudden cardiac death in mice lacking all NO synthases fed a high-fat diet

• Published in: Cardiovascular research 2010-09, Vol.87 (4), p.675-682
• Main Authors: Yatera, Yasuko, Shibata, Kiyoko, Furuno, Yumi, Sabanai, Ken, Morisada, Naoya, Nakata, Sei, Morishita, Tsuyoshi, Toyohira, Yumiko, Wang, Ke-Yong, Tanimoto, Akihide, Sasaguri, Yasuyuki, Tasaki, Hiromi, Nakashima, Yasuhide, Shimokawa, Hiroaki, Yanagihara, Nobuyuki, Otsuji, Yutaka, Tsutsui, Masato
• Format: Article
• Language: English
• Subjects: Animals; Aorta - enzymology; Aorta - pathology; Apolipoproteins E - blood; Atherosclerosis; Atherosclerosis - enzymology; Atherosclerosis - genetics; Atherosclerosis - pathology; Atherosclerosis - physiopathology; Biomarkers - blood; Biomarkers - urine; Blood Pressure; C-Reactive Protein - metabolism; Cholesterol, Dietary - blood; Cholesterol, Dietary - metabolism; Cholesterol, LDL - blood; Death, Sudden, Cardiac - etiology; Death, Sudden, Cardiac - pathology; Dinoprost - analogs & derivatives; Dinoprost - urine; Disease Models, Animal; Dyslipidemias - enzymology; Dyslipidemias - genetics; Dyslipidemias - pathology; Dyslipidemias - physiopathology; Genotype; Liver - enzymology; Male; Membrane Transport Proteins - metabolism; Mice; Mice, Inbred C57BL; Mice, Knockout; Myocardium - enzymology; Nitric oxide; Nitric oxide synthase; Nitric Oxide Synthase - deficiency; Nitric Oxide Synthase - genetics; Nitric Oxide Synthase Type I - deficiency; Nitric Oxide Synthase Type I - genetics; Nitric Oxide Synthase Type II - deficiency; Nitric Oxide Synthase Type II - genetics; Nitric Oxide Synthase Type III - deficiency; Nitric Oxide Synthase Type III - genetics; Peptidyl-Dipeptidase A - metabolism; Phenotype; Receptors, LDL - metabolism; Severity of Illness Index; Sterol Regulatory Element Binding Protein 2 - metabolism; Time Factors
• ISSN: 0008-6363; 1755-3245
• DOI: 10.1093/cvr/cvq092

Aims The precise role of the nitric oxide synthase (NOS) system in lipid metabolism remains to be elucidated. We addressed this point in mice that we have recently developed and that lack all three NOS isoforms. Methods and results Wild-type (WT), singly, doubly, and triply NOS−/− mice were fed either a regular or high-cholesterol diet for 3–5 months. The high-cholesterol diet significantly increased serum low-density lipoprotein (LDL) cholesterol levels in all the genotypes when compared with the regular diet. Importantly, when compared with the WT genotype, the serum LDL cholesterol levels in the high-cholesterol diet were significantly and markedly elevated only in the triply NOS−/− genotype, but not in any singly or doubly NOS−/− genotypes, and this was associated with remarkable atherosclerosis and sudden cardiac death, which occurred mainly in the 4–5 months after the high-cholesterol diet. Finally, hepatic LDL receptor expression was markedly reduced only in the triply NOS−/− genotype, accounting for the diet-induced dyslipidaemia in the genotype. Conclusion These results provide the first direct evidence that complete disruption of all NOS genes causes severe dyslipidaemia, atherosclerosis, and sudden cardiac death in response to a high-fat diet in mice in vivo through the down-regulation of the hepatic LDL receptor, demonstrating the critical role of the whole endogenous NOS system in maintaining lipid homeostasis.