Effect of Therapeutic Pulsed Ultrasound on Lipoperoxidation and Fibrogenesis in an Animal Model of Wound Healing

Evidence from the literature has shown that the wound healing process is enhanced by ultrasound therapy. In the present study, we measured thiobarbituric acid-reactive substances (TBARS; index of lipo-peroxidation) and hydroxyproline (index of collagen synthesis) levels in wounds after therapeutic pulsed ultrasound (TPU) treatment. Male Wistar rats were submitted to skin ulceration, and three doses of TPU (0.4, 0.6, and 0.8W/cm(2)) were used. A circular area of skin was removed with a punch biopsy from the medial dorsal region. After TPU for 10 days, TBARS (Draper and Hadley [21]) and hydroxyproline (Woessner [22]) levels were measured in the tissue around the wound. Results showed that TPU improved wound healing, since the wound size was significantly smaller 5 and 10 days after ulceration in groups submitted to this treatment. Moreover, TBARS levels were decreased in the 0.4, 0.6, and 0.8W/cm(2) TPU groups, and hydroxyproline levels were increased in the 0.6 and 0.8W/cm(2) TPU groups. These findings indicate that TPU presents beneficial effects on the wound healing process, probably by speeding up the inflammatory phase and inducing collagen synthesis. (C) 2010 Elsevier Inc. All rights reserved.