Exploration of the anti-inflammatory, analgesic, and wound healing activities of Bletilla Striata polysaccharide

Abstract

Bletilla Striata (BS) Polysaccharide (BSP) is one of the main components of the traditional Chinese medicinal plant Bletilla striata Rchb. F. BSP has been widely used in antimicrobial and hemostasis treatments in clinics. Despite its use in skin disease treatment and cosmetology, the effects of BSP on wound healing remain unclear. Here we investigated the anti-inflammatory, antioxidant, and analgesic effects of BSP and explored its impact on morphological changes and inflammatory mediators during wound healing. A carrageenan-induced mouse paw edema model was established to evaluate the anti-inflammatory effect of BSP. Antioxidant indicators, including NO, SOD, and MDA, were measured in the blood and liver. The increased pain threshold induced by BSP was also determined using the hot plate test. A mouse excisional wound model was applied to evaluate the wound healing rate, and HE staining and Masson staining were used to detect tissue structure changes. In addition, ELISA was employed to detect the expression of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β in serum. BSP significantly decreased the concentration of NO and MDA in serum and liver while increasing SOD activity. It exhibited a notable improvement in mouse paw edema induced by carrageenan. BSP dose-dependently delayed the appearance of licking behavior in mice, indicating its analgesic effect. Compared to the control group, the wound healing rate was significantly improved in the BSP treatment group. HE and Masson staining results showed that the BSP and 'Jingwanhong' ointment groups had slightly milder inflammatory responses and significantly promoted more new granulation tissue formation. The levels of serum inflammatory mediators TNF-α, IL-1β, and IL-6 were reduced to varying degrees. The results demonstrated that BSP possesses anti-inflammatory, antioxidant, analgesic, and wound healing properties, and it may promote wound healing through inhibition of inflammatory cytokine synthesis and release.

Keywords: Analgesic; Anti-inflammatory; Bletilla striata polysaccharide; Inflammatory indicator; Wound healing.