Effect of salvia miltiorrhiza combined with roxadustat on wound healing of full-thickness skin defects in diabetic rats and its mechanism
Objective To explore the effect of salvia miltiorrhiza combined with roxadustat on wound healing of full-thickness skin defects in diabetic rats and its mechanism.Methods This study was an experimental study.Twenty male 8-week-old Sprague-Dawley rats were used to successfully establish diabetic model,then full-thickness skin defect wounds on their backs were made.The rats were divided into normal saline group,roxadustat alone group,salvia miltiorrhiza alone group,and roxadustat+salvia miltiorrhiza group according to the random number table,with 5 rats in each group.Immediately after injury,the rats in normal saline group were given 5 mL normal saline by gavage,the rats in roxadustat alone group were given 1.5 mg/mL roxadustat suspension by gavage at 25 mg/kg,the rats in salvia miltiorrhiza alone group were given 18 mg/mL salvia miltiorrhiza suspension by gavage at 300 mg/kg,and the rats in roxadustat+salvia miltiorrhiza group were given 19.5 mg/mL roxadustat and salvia miltiorrhiza suspension at roxadustat 25 mg/kg and salvia miltiorrhiza 300 mg/kg.All were administered once a day for 2 weeks.The wounds at 0(immediately),4,8,and 12 d after injury were observed,and the wound healing rates at 4,8,and 12 d after injury were calculated(n=5).At 14 d after injury,abdominal aortic blood was collected,and hemoglobin,red cell count,and white blood cell count were detected(n=5).The wound tissue was collected for hematoxylin-eosin staining to observe inflammatory infiltration,skin tissue structure,and neovascularization,for Masson staining to observe the proportion of collagen fiber(n=3),for Western blotting to detect the protein expression levels of vascular endothelial growth factor(VEGF),CD31,interleukin 6(IL-6),tumor necrosis factor α(TNF-α),and IL-1β(n=3),and for immunohistochemical staining to determine the protein expression levels of epidermal growth factor receptor(EGFR),hypoxia-inducible factor 1α(HIF-1α),and proliferating cell nuclear antigen(PCNA),with sample number of 3.Results From 0 to 12 d after injury,the wound areas of rats in 4 groups were gradually decreased.At 4 d after injury,the wound healing rates of rats in salvia miltiorrhiza alone group and roxadustat+salvia miltiorrhiza group were significantly higher than those in normal saline group and roxadustat alone group(P＜0.05).At 8 d after injury,the wound healing rates of rats in roxadustat alone group and salvia miltiorrhiza alone group were significantly higher than the rate in normal saline group(P＜0.05),and the wound healing rate of rats in roxadustat+salvia miltiorrhiza group was significantly higher than the rates in the other 3 groups(with P values all＜0.05).At 12 d after injury,the wound healing rates of rats in roxadustat alone group,salvia miltiorrhiza alone group,and roxadustat+salvia miltiorrhiza group were significantly higher than the rate in normal saline group(P＜0.05).At 14 d after injury,there were no statistically significant differences in the hemoglobin or red blood cell count of rats in 4 groups(P＜0.05).The white blood cell count of rats in roxadustat alone group,salvia miltiorrhiza alone group,and roxadustat+salvia miltiorrhiza group were respectively(24.3±1.2)×109/L,(26.3±2.4)×109/L,and(15.0±0.7)×109/L,which were significantly lower than(33.8±2.7)×109/L in normal saline group(P＜0.05);the white blood cell count of rats in roxadustat+salvia miltiorrhiza group was significantly lower than that in roxadustat alone group and salvia miltiorrhiza alone group(with P values both＜0.05).At 14 d after injury,a large number of inflammatory cell infiltration,disordered skin tissue structure,and few new blood vessels were observed in the wounds of rats in normal saline group;while a small amount of inflammatory cell infiltration,tight skin tissue structure,and rich neovascularization were observed in the wounds of rats in the other 3 groups.There were no statistically significant differences in the proportion of collagen fiber of wounds in rats among the 4 groups(P＞0.05).At 14 d after injury,the protein expression levels of VEGF and CD31 in the wound tissue of rats in roxadustat alone group,salvia miltiorrhiza alone group,and roxadustat+salvia miltiorrhiza group were significantly higher than those in normal saline group(P＜0.05),the protein expression level of CD31 in the wound tissue of rats in roxadustat+salvia miltiorrhiza group was significantly higher than the levels in roxadustat alone group and salvia miltiorrhiza alone group(with P values both＜0.05).At 14 d after injury,the protein expression levels of IL-6,TNF-α,and IL-1β in the wound tissue of rats in roxadustat alone group,salvia miltiorrhiza alone group,and roxadustat+salvia miltiorrhiza group were significantly lower than those in normal saline group(P＜0.05);the protein expression levels of IL-6 and IL-1β in the wound tissue of rats in roxadustat+salvia miltiorrhiza group were significantly lower than those in roxadustat alone group and salvia miltiorrhiza alone group(P＜0.05);the protein expression level of TNF-α in the wound tissue of rats in roxadustat+salvia miltiorrhiza group was significantly lower than that in salvia miltiorrhiza alone group(P＜0.05).At 14 d after injury,the protein expression level of EGFR in the wound tissue of rats in roxadustat+salvia miltiorrhiza group was significantly higher than the levels in the other 3 groups(with P values all＜0.05);the protein expression levels of HIF-1α in the wound tissue of rats in roxadustat alone group and roxadustat+salvia miltiorrhiza group were significantly higher than the level in normal saline group(P＜0.05),and the protein expression level of HIF-1α in the wound tissue of rats in roxadustat+salvia miltiorrhiza group was significantly higher than that in salvia miltiorrhiza alone group(P＜0.05);there were no statistically significant differences in the protein expression level of PCNA in the wound tissue of rats in 4 groups(P＞0.05).Conclusions Roxadustat combined with salvia miltiorrhiza can promote the wound healing of full-thickness skin defects in diabetic rats by promoting blood vessel regeneration and reducing inflammatory response.
万方数据
维普
