Pulsed Electromagnetic Fields Increase Angiogenesis and Improve Cardiac Function After Myocardial Ischemia in Mice

Abstract

Background: Previous studies have shown that pulsed electromagnetic fields (PEMF) stimulate angiogenesis and may be a potential treatment strategy to improve cardiac function after myocardial infarction (MI). This study explored the effects and its related mechanisms of PEMF in MI mice. Methods and Results: MI mice were used in PEMF treatment (15 Hz 1.5 mT PEMF or 30 Hz 3.0 mT PEMF) for 45 min per day for 2 weeks. Furthermore, an in vivo Matrigel plug assay was used to observe the effect of PEMF in promoting angiogenesis. Compared with the sham PEMF group, PEMF treatment with 30 Hz 3.0 mT significantly improved heart function. PEMF treatment with 15 Hz 1.5 mT and 30 Hz 3.0 mT both increased capillary density, decreased infarction area size, increased the protein expression of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor 2 (VEGFR2), Ser473-phosphorylated Akt (p Ser473-Akt) and S1177-phosphorylated endothelial nitric oxide synthase (p S1177-eNOS), and increased the mRNA level of VEGF and hypoxia inducible factor 1-alpha (HIF-1α) in the infarct border zone. Additionally, treatment with 30 Hz 3.0 mT also increased protein and mRNA level of fibroblast growth factor 2 (FGF2), and protein level of β1 integrin, and shows a stronger therapeutic effect. Conclusions: PEMF treatment could promote angiogenesis of the infarct border zone and improve cardiac function in MI mice. A treatment parameter of 30 Hz 3.0 mT is remarkably effective in MI mice. The effect is associated with the proangiogenic signaling pathways of HIF-1α/VEGF/Akt/eNOS or HIF-1α/FGF2/Akt/eNOS.

Effects of Acute Low-Frequency Pulsed Electromagnetic Field Therapy on Aerobic Performance during a Preseason Training Camp: A Pilot Study

“…Based on our findings, the improvement was likely due to enhanced angiogenesis in the PEMF group. The majority of evidence supporting a link between PEMF and promotion of angiogenesis is from clinical studies [ 30 , 31 , 32 , 33 ], rather than an athletic setting. Nevertheless, because athletic performance, specifically high-intensity running, can cause hypoxic conditions within exercising skeletal muscle [ 34 ], translation of clinical findings to an athletic scenario may be viable.…”

“…Nevertheless, because athletic performance, specifically high-intensity running, can cause hypoxic conditions within exercising skeletal muscle [ 34 ], translation of clinical findings to an athletic scenario may be viable. In particular, PEMF-induced angiogenesis has been observed in diseases where ischemia and hypoxia are major problems, such as myocardial infarction [ 30 , 35 ] peripheral arterial disease [ 31 ], and diabetes [ 36 ]. In these diseases, ischemia and subsequent tissue hypoxia are contributing factors to both the underlying pathogenesis and the symptomatic manifestations of the disease.…”

The Effect of Pulsed Electromagnetic Fields on Angiogenesis

“…Some experiments with the myocardial infarction model have revealed the role of PEMF on angiogenesis. Three experiments [Albertini et al, 1999; Yuan et al, 2010; Hao et al, 2014] have investigated the effects of PEMF on myocardial infarction in rats and one [Peng et al, 2020] in mice and two experiments [Albertini et al, 1999; Ma et al, 2016] have researched the effects of PEMF on myocardial ischemia‐reperfusion (I/R) injury in rats. The results of these experiments showed that PEMF improved cardiac function, limited the expansion of infarction, and improved cardiac remodeling by promoting angiogenesis.…”

“…They found that PEMF stimulation of 10 Hz 4m T or 15 Hz 6 mT may increase myocardial capillary density, and then result in decreased left ventricular end‐diastolic pressure (LVEDP), increased left ventricular pressure maximal rise rate (LV + dp / dt max ), and decreased ventricular mass and myocardial infarct area [Yuan et al, 2010]. Other studies reported that 30 Hz 3 mT PEMF increased ejection fraction (EF) and fractional shortening (FS) [Peng et al, 2020], and 30 Hz PEMF activated the HIF‐1α/Akt axis in the infarct border area [Hao et al, 2014; Peng et al, 2020]. In the study of Ma et al [2016], the effect of PEMF on myocardial I/R injury was proven for the first time: the number and function of circulating endothelial progenitor cells (EPCs) increased in I/R rats treated with 30 Hz PEMF [Ma et al, 2016].…”

An eight-week pulsed electromagnetic field improves physical functional performance and ankle-brachial index in men with Fontaine stage II peripheral artery disease

“…The pulsed electromagnetic field (PEMF) has recently gained attention by researchers involved in the realm of cardiovascular disease management owing to its multiple therapeutic benefits. There has been considerable evidence supporting the cardiovascular effects of PEMF in terms of stimulating angiogenesis and preserving cardiac function in rat models with ischemic lesions [5,6], improving flow-mediated dilatation and blood pressure in hypertensive subjects [7], increasing nitric oxide bioavailability, and reducing blood pressure in metabolic syndrome [8], as well as reducing the intimal medial thickness, increasing blood flow velocity, and improving the ankle-brachial index (ABI) in patients with PAD [9,10]. Yet, there is insufficient evidence to support the functional outcomes of PEMF in terms of enhanced walking/physical functional performance, particularly, in patients with PAD.…”