Effect of compound chamomile and lidocaine hydrochloride gel on skin wound healing in rats

Objective To explore the effect and mechanism of compound chamomile and lidocaine hydrochloride gel on skin wound healing in rats.

Methods The model rats with skin wound was established by surgical resection, and the rats were randomly divided into experimental group (treated with compound chamomile and lidocaine hydrochloride gel), positive drug group (treated with compound polymyxin B ointment) and model group (treated with normal saline). At 7 and 14 days of treatment, the wound size of rats in each group was measured. Tumor necrosis factor-α (TNF- α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) levels in wound tissues were detected by enzyme-linked immunosorbent assay (ELISA). The expression levels of CD68, CD163 and CC chemokine receptor 7 (CCR7) in the wound tissues were detected by immunohistochemistry, and the change of macrophage phenotype was observed. The distribution of collagen in wound tissues was observed by Picric acid Sirius red staining.

Results After 7 days of treatment, the inflammatory cells and blood vessels decreased while the fibroblasts increased in the experimental group, which was more advantageous than the positive drug group. At the 14th day of treatment, the wound healing of the experimental group was mainly composed of fibroblasts and collagen, and there was no significant difference between the experimental group and the positive drug group (P>0.05). At 7 days of treatment, the expression levels of TNF-α, IL-6 and IL-1β in the experimental group were significantly lower than those of model group and positive drug group (P < 0.05 or P < 0.01). After 14 days of treatment, there were no significant differences in the expression levels of TNF-α, IL-6 and IL-1β in the wound tissues of rats between groups (P>0.05). At 7 and 14 days of treatment, the collagen content in the experimental group increased significantly, but the phenotype of macrophages did not change obviously.

Conclusion Compound chamomile and lidocaine hydrochloride gel has good anti-inflammatory and healing effects on skin wounds, and inhibiting the release of inflammatory factors may be one of its main mechanisms.