Repeated sauna therapy attenuates ventricular remodeling after myocardial infarction in rats by increasing coronary vascularity of noninfarcted myocardium

Abstract

Repeated sauna therapy (ST) increases endothelial nitric oxide synthase (eNOS) activity and improves cardiac function in heart failure as well as peripheral blood flow in ischemic limbs. The present study investigates whether ST can increase coronary vascularity and thus attenuate cardiac remodeling after myocardial infarction (MI). We induced MI by ligating the left coronary artery of Wistar rats. The rats were placed in a far-infrared dry sauna at 41°C for 15 min and then at 34°C for 20 min once daily for 4 wk. Cardiac hemodynamic, histopathological, and gene analyses were performed. Despite the similar sizes of MI between the ST and non-ST groups (51.4 ± 0.3 vs. 51.1 ± 0.2%), ST reduced left ventricular (LV) end-diastolic (9.7 ± 0.4 vs. 10.7 ± 0.5 mm, P < 0.01) and end-systolic (8.6 ± 0.5 vs. 9.6 ± 0.6 mm, P < 0.01) dimensions and attenuated MI-induced increases in LV end-diastolic pressure. Cross-sectional areas of cardiomyocytes were smaller in ST rats and associated with a significant reduction in myocardial atrial natriuretic peptide mRNA levels. Vascular density was reduced in the noninfarcted myocardium of non-ST rats, and the density of cells positive for CD31 and for α-smooth muscle actin was decreased. These decreases were attenuated in ST rats compared with non-ST rats and associated with increases in myocardial eNOS and vascular endothelial growth factor mRNA levels. In conclusion, ST attenuates cardiac remodeling after MI, at least in part, through improving coronary vascularity in the noninfarcted myocardium. Repeated ST might serve as a novel noninvasive therapy for patients with MI.

Heat therapy promotes the expression of angiogenic regulators in human skeletal muscle

“…Several animal studies demonstrated unequivocally that heat therapy promotes angiogenesis in the heart (21,28,69) and in skeletal muscle (1,40,43), but the molecular mechanisms underlying this adaptation remain poorly defined. One attractive candidate is VEGF, a potent angiogenic inducer that acts by promoting proliferation and enhancing migration and invasion of endothelial cells (5).…”

“…One attractive candidate is VEGF, a potent angiogenic inducer that acts by promoting proliferation and enhancing migration and invasion of endothelial cells (5). Increased capillarization in the myocardium following whole body heat stress in rats is, indeed, associated with a marked upregulation of VEGF expression (21,28,69). In the present study, an increase in VEGF mRNA expression in skeletal muscle was observed following both LBH and TH, demonstrating that this central proangiogenic factor might also mediate the angiogenic response to heat therapy in skeletal muscle.…”

“…The exact mechanisms underlying these documented clinical benefits are unclear, but several pieces of evidence indicate that heat therapy might work, in part, by promoting angiogenesis. First, whole body heat stress induced by far-infrared dry sauna or a heating blanket promotes the expression of the proangiogenic mediator vascular endothelial growth factor (VEGF) and increases capillary density in the myocardium in healthy (21) and hypertensive (28) rats, as well as in a model of myocardial infarction (69). Second, repeated treatment with far infrared dry sauna increases skeletal muscle capillary density in a mouse model of PAD (1,40) and diabetes (26) and in rats treated with glucocorticoids (43).…”

Waon Therapy Improves Quality of Life as Well as Cardiac Function and Exercise Capacity in Patients With Chronic Heart Failure

“…[1][2][3] The precise mechanisms of the salutary effects of WT in CHF treatment are not yet fully understood, although WT-induced vasodilation and improvement of endothelial function through up-regulation of endothelial nitric oxide synthase (eNOS) could contribute to the beneficial effects. 4,5) Depressive symptoms are common in patients with CHF and many CHF patients have impairment of all aspects of their quality of life (QOL) as assessed by SF-36 scores. 6) Moreover, having depressive illness or impaired QOL in CHF patients is linked to a worse prognosis.…”

The Effect of Thermal Therapy on Uremic Pruritus in Hemodialysis Patients

“…Thus, thermotherapy using electromagnetic FIR waves is considered as an effective type of physiotherapy for improving the health of patients with cardiovascular disease, diabetes, and chronic kidney disease. The usefulness of FIR and its positive protective effects have been proven on endothelium (26).…”