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BH4 Increases nNOS Activity and Preserves Left Ventricular Function in Diabetes
- Source :
- Circ Res, CIRCULATION RESEARCH, r-IIS La Fe. Repositorio Institucional de Producción Científica del Instituto de Investigación Sanitaria La Fe, instname
- Publication Year :
- 2021
-
Abstract
- Rationale: In diabetic patients, heart failure with predominant left ventricular (LV) diastolic dysfunction is a common complication for which there is no effective treatment. Oxidation of the NOS (nitric oxide synthase) cofactor tetrahydrobiopterin (BH4) and dysfunctional NOS activity have been implicated in the pathogenesis of the diabetic vascular and cardiomyopathic phenotype. Objective: Using mice models and human myocardial samples, we evaluated whether and by which mechanism increasing myocardial BH4 availability prevented or reversed LV dysfunction induced by diabetes. Methods and Results: In contrast to the vascular endothelium, BH4 levels, superoxide production, and NOS activity (by liquid chromatography) did not differ in the LV myocardium of diabetic mice or in atrial tissue from diabetic patients. Nevertheless, the impairment in both cardiomyocyte relaxation and [Ca 2+ ]i (intracellular calcium) decay and in vivo LV function (echocardiography and tissue Doppler) that developed in wild-type mice 12 weeks post–diabetes induction (streptozotocin, 42–45 mg/kg) was prevented in mGCH1-Tg (mice with elevated myocardial BH4 content secondary to trangenic overexpression of GTP-cyclohydrolase 1) and reversed in wild-type mice receiving oral BH4 supplementation from the 12th to the 18th week after diabetes induction. The protective effect of BH4 was abolished by CRISPR/Cas9-mediated knockout of nNOS (the neuronal NOS isoform) in mGCH1-Tg. In HEK (human embryonic kidney) cells, S-nitrosoglutathione led to a PKG (protein kinase G)-dependent increase in plasmalemmal density of the insulin-independent glucose transporter GLUT-1 (glucose transporter-1). In cardiomyocytes, mGCH1 overexpression induced a NO/sGC (soluble guanylate cyclase)/PKG–dependent increase in glucose uptake via GLUT-1, which was instrumental in preserving mitochondrial creatine kinase activity, oxygen consumption rate, LV energetics (by 31 phosphorous magnetic resonance spectroscopy), and myocardial function. Conclusions: We uncovered a novel mechanism whereby myocardial BH4 prevents and reverses LV diastolic and systolic dysfunction associated with diabetes via an nNOS-mediated increase in insulin-independent myocardial glucose uptake and utilization. These findings highlight the potential of GCH1/BH4–based therapeutics in human diabetic cardiomyopathy. Graphic Abstract: A graphic abstract is available for this article.
- Subjects :
- 0301 basic medicine
cardiovascular disease, glucose, heart failure, mice, nitric oxide synthase
medicine.medical_specialty
Physiology
Diabetic Cardiomyopathies
Diastole
Nitric Oxide Synthase Type I
030204 cardiovascular system & hematology
Article
03 medical and health sciences
Mice
Ventricular Dysfunction, Left
0302 clinical medicine
Text mining
Internal medicine
Diabetes mellitus
medicine
Effective treatment
Animals
Humans
Myocytes, Cardiac
GTP Cyclohydrolase
Glucose Transporter Type 1
biology
Ventricular function
business.industry
medicine.disease
Biopterin
Glutathione
Nitric oxide synthase
Mice, Inbred C57BL
030104 developmental biology
Glucose
HEK293 Cells
Heart failure
biology.protein
Cardiology
cardiovascular system
Cardiology and Cardiovascular Medicine
business
Complication
Subjects
Details
- ISSN :
- 15244571 and 00097330
- Volume :
- 128
- Issue :
- 5
- Database :
- OpenAIRE
- Journal :
- Circulation research
- Accession number :
- edsair.doi.dedup.....c1f58f0b9789a0b049d23bdbbd2346cb