Angiogenic effect of the aqueous extract of Cynodon dactylon on human umbilical vein endothelial cells and granulation tissue in rat.

BACKGROUND: Cynodon dactylon, a valuable medicinal plant, is widely used in Iranian folk medicine for the treatment of various cardiovascular diseases such as heart failure and atherosclerosis. Moreover, its anti-diabetic, anti-cancer and anti-microbial properties have been also reported. Concerning the critical role of angiogenesis in the incidence and progression of tumors and also its protective role in cardiovascular diseases, we investigated the effects of the aqueous extract prepared from the rhizomes of C. dactylon on vascular endothelial growth factor (VEGF) expressions in Human Umbilical Vein Endothelial Cells (HUVECs) and also on angiogenesis in carrageenan induced air-pouch model in rats. METHODS: In the air-pouch model, carrageenan was injected into an air-pouch on the back of the rats and following an IV injection of carmine red dye on day 6, granulation tissue was processed for the assessment of the dye content. Furthermore, in an in vitro study, angiogenic property of the extract was assessed through its effect on VEGF expression in HUVECs. RESULTS: Oral administration of 400 mg/kg/day of the extract significantly increased angiogenesis (p<0.05) and markedly decreased neutrophil (p<0.05) and total leukocyte infiltration (p<0.001) into the granulation tissues. Moreover, the extract increased the expression of total VEGF in HUVECs at a concentration of (100 µl/ml). CONCLUSION: The present study showed that the aqueous extract of C. dactylon promotes angiogenesis probably through stimulating VEGF expression.

[Effects of reinforcing qi and nourishing blood recipes on vascular endothelial growth factor and microvessel count in granulation tissue in rats with chronic skin ulcers].

OBJECTIVE: To explore the effects of reinforcing qi and nourishing blood recipes on vascular endothelial growth factor (VEGF) and the microvessel count (MVC)in granulation tissue in rats with chronic skin ulcers. METHODS: A total of 90 male SD rats with back full-thickness skin lesion were used in this study. Except for the normal control group, the rats were injected with hydrocortisone for inducing chronic skin ulcers, and were randomly divided into untreated group, Sijunzi Decoction group, Siwu Decoction group and Bazhen Decoction group. The time of wound healing was observed; immunohistochemical method and image analytical method were used to test the expressions of VEGF and MVC in granulation tissue of dermal chronic ulcers in the rats. RESULTS: In the untreated group, the time of wound healing was significantly longer than that in the normal group (P<0.01). The time of wound healing was obviously shortened in the three treated groups as compared with the untreated group (P<0.01, P<0.05). In the Sijunzi Decoction group, the time of wound healing was obviously shorter than those in Siwu Decoction group and Bazhen Decoction group (P<0.05, P<0.01). In the untreated group, the expression of VEGF and MVC were significantly lower than those in the normal control group (P<0.01). The expression of VEGF and MVC were obviously increased in the three treated groups as compared with those in the untreated group (P<0.01, P<0.05). In the Sijunzi Decoction group, the expression of VEGF and MVC were obviously lower than those in Siwu Decoction group and Bazhen Decoction group (P<0.05, P<0.01). CONCLUSION: Reinforcing qi and nourishing blood recipes can promote wound healing in rats through up-regulating the expression of VEGF in granulation tissue of dermal chronic ulcers, and inducing angiogenesis.

Enhanced wound contraction in fresh wounds dressed with honey in Wistar rats (Rattus Novergicus).

BACKGROUND: Due to reports that honey accelerates wound healing, an investigation on its role in wound contraction in fresh wounds inflicted on wistar rats was carried out. METHOD: Twenty adult male wistar rats had 2cm by 2cm square wound inflicted on their right dorsolateral trunk. They were divided into two groups. The experimental group had their wounds dressed with honey while the control group had normal saline dressing. Wound dressing was done every five days and measurements taken at each dressing. Wound morphology was also assessed. RESULTS: Dressing with honey significantly enhanced percentage wound contraction on day 10 with value of 79.20+/-2.94 compared to control value of 53.50+/-4.32. p=0.0. The mean wound measurement on day 10 reduced significantly in honey group, 1.15+/-0.18 compared to control group 2.38+/-0.28. p=0.002. However, there was no significant difference in fibroblast count per high power field in honey group 68.0+/-2.59 compared to control 90.2+/-17.40, p=0.242. Honey dressing increased mean blood vessel count per high power field, 18.8+/-3.77 albeit non significantly when compared to control value of 13.4+/-2.44, p=0.264. Also honey dressing caused increased granulation tissue formation in wounds dressed with honey compared to control group. CONCLUSION: Our study suggests that honey dressing enhances wound contraction in fresh wounds which is one of the key features of wound healing.