Effects of Electrical Stimulation on the Expression of Angiogenic Growth Factor and Wound Healing

The use of electrical stimulation for the treatment of chronic wounds is not a new issue, and its history dates back to ۳۰۰ years ago, when gold leaves were used to prevent smallpox wounds. During the last few decades, the beneficial and positive effects of electrical stimulation have been reported in human and animal models, so that there are many evidences in support of the use of electrical stimulation for wound healing. In general, three types of electric current have been proposed with therapeutic application for wound healing; direct current, pulsed current and alternating current. In most studies, only DC and PC currents have been used for wound healing. Recently, it has been reported that it has profound and extensive effects on the angiogenesis process. One of the proposed mechanisms for electrical stimulation in connection with wound healing is the angiogenic effects of electrical stimulation in the wound healing process. The increase of angiogenesis by electrical stimulation, both with an intensity at the limit of skeletal muscle contraction or an intensity below the threshold of contraction in ischemic and non-ischemic muscles, through the increase of angiogenic factors such as VEGF. In the studies conducted on animal and human wounds, it has been observed by performing a biopsy of the wound tissue that electrical stimulation increases the expression of angiogenic factors (VEGF, FGF), the density of capillary vessels and angiogenesis in the wound tissue. The results of our previous study on diabetic foot ulcers showed that electrical stimulation can increase the release of VEGF in diabetic foot ulcers. The pattern of VEGF release in diabetic wounds in the stimulation group was different from the placebo. In the first session, immediately after applying electrical stimulation, the amount of VEGF increased significantly compared to the baseline value before stimulation. In the twelfth (last) session, similar to the first session, immediately after applying electrical stimulation, the amount of VEGF in the wound fluid compared to before Stimulation also showed a significant increase compared to the baseline value in the first session.based on the available evidence, It can be concluded that application of ES can increases the release of angiogenic factors such as of VEGF in wound site, which may lead to improved angiogenesis and accelerate wound closing in chronic wound such as diabetic foot ulcers.