Effects of hyperbaric oxygen therapy on circulating interleukin-8, nitric oxide, and insulin-like growth factors in patients with type 2 diabetes mellitus

Abstract

Background: The potential benefits of hyperbaric oxygen therapy (HBOT) have been reported in diabetic patients with foot ulcers. However, the roles of HBOT on wound healing-associated growth factors and inflammatory mediators are not completely understood in diabetes mellitus (DM). Objectives: The aim of this study was to investigate the effects of HBOT on circulating cytokines, NO, and insulin-like growth factors (IGF) in patients with type 2 DM. Design and methods: Serum samples were collected from patients with type 2 DM ( n = 31) and healthy subjects ( n = 29) before (baseline) and after the first and third exposure. Results: Before HBOT, body mass index (BMI) and serum HbA1c were significantly greater, whereas serum IGF-I was significantly lower in diabetic patients compared to healthy subjects (one-way ANOVA, p < 0.05). After adjusting for age, gender, and BMI, serum insulin, growth hormone (GH), IGF-II, IGF-binding protein (IGFBP)-1, IGFBP-3, leptin, interleukin (IL)-8, and NO were not significantly altered by HBOT in diabetic patients and healthy subjects (repeated-measures ANOVA). Change in serum insulin (baseline to the third exposure) was a positive predictor of changes in leptin and NO in healthy subjects and diabetic patients, respectively. Conclusions: Our results suggest that short-term HBOT may not alter the circulating insulin, IGF, leptin, IL-8, and NO levels. In addition, healthy subjects and diabetic patients showed differential responses to HBOT in the relationships of leptin, insulin, and NO. Further studies are needed to clarify the mechanism of HBOT-improved wound healing in diabetic patients with foot ulcers.