Effects of medicinal mushroom (Sparassis crispa) on wound healing in streptozotocin-induced diabetic rats.

BACKGROUND: The impaired wound healing in diabetes mellitus is a major clinical problem. Sparassis crispa (SC) is a medicinal mushroom and its beta-glucan content is more than 40%. This study investigated whether oral administration of SC could improve the impaired wound healing in diabetic rats. METHODS: Full-thickness skin wounds were created on the backs of streptozotocin (STZ)-induced diabetic rats. Diabetic rats were then divided into 2 groups: SC-treated group that was orally administered doses of 1,000 mg/kg body weight per day of SC for 4 weeks and a control group without SC administration. Moreover, collagen synthesis of purified beta-glucan from SC was estimated in vitro. RESULTS: Wound closure was significantly accelerated by oral administration of SC. Furthermore, in SC-treated wounds there were significant increases in macrophage and fibroblast migration, collagen regeneration, and epithelialization compared with the control group. The levels of type I collagen synthesized by cultured human dermal fibroblasts for the SC group were significantly higher than those for the control group. CONCLUSIONS: SC can improve the impaired healing of diabetic wounds. This effect might involve an increase in the migration of macrophages and fibroblasts, and beta-glucan from SC directly increases the synthesis of type I collagen. Therefore, the use of SC may be extended to the clinical setting and prove an effective promoter of wound healing in patients with diabetes.