The Mechanism And Effects Of Emu Oil On Wound Healing In Scalded Rats

SUPPORTED BYKey Program of Natural Science Foundation of Guangdong Province, NO. 020089.AIMTo observe the effects of topical emu oil on concrescence of superficial second degree burn wound of rats, and to discuss the mechanism of accelerating wound healing.METHODSTo establish the model of rats. 108 Wistar rats with superficial second degree burn were randomly and equally divided into simple burn group(group A), povidone iodine group (group B) and emu oil group(group C). After burn, all the wounds were covered by normal saline gauze, povidone iodine gauze, and emu oil gauze, respectively. Then all the rats were bound by axenic gauze, back to feed in their separate cages,and the medicine was changed once daily. The wound tissues were taken at days 1,3,5,10 and 14 after burn,and were executed paraffin slice.The wound was observed: The inflammation reaction of wound was observed every day;The healing time was observed: 6 rats of every group were observed about the time of wound healing,according to epithelization of the whole wound.The healing rate were observed: 6 rats of every group were observed about the wound concrescence rate (the 7~th, 10~th, 14~thday).The pathologic and tissue morphological change was observed: The tissue morphological change on pathology slice was observed after hematoxylin and eosin(HE) staining.Immunohistochemical staining of proliferating cell nuclear antigen (PCN A):SABC immunohistochemical staining was performed to evaluate the expression ofPCNA in burn wound(the 5th, 10th, 14lhday).The PCNA positive cells were measured by Labeling index (LI).Immunohistochemical staining of Keratin 10(K10) and Keratin 14(K14): The expression of K10 in burn wound was detected by Keratin 10 Ab-1 and SP immunohistochemical staining(the 10th, 14thday).The difference of the groups was observed. The expression of K14 in burn wound was detected by Keratin 14 Ab-1 and SP immunohistochemical staining(the 10th, 14thday).The difference of the groups was observed.Immunohistochemical staining of epidermal growth factor (EGF) : The expression of EGF in burn wound was detected by Rabbit Anti -EGF and SP immunohistochemical staining(the 5th ,10th, 14thday).The difference of the groups was observed.the cell positive rate was count.All data was expressed by Mean±SD,and was Statisticed in SPSS 10.0 by Oneway ANOVA,Repeated Measures and Factorial analysis.RESULTSCompared with groups A,B, the swelling and effusion of the wound was reduced in group C. The time for wound healing in group C was significantly shorter than that in the others (One- way ANOVA, F= 15.00, P<0.01) . The wound healing rate was significantly higher in group C than in the others (Repeated Measures, F=443.96, P<0.01) .It is shown by the analysis of pathological sections that the early inflammatory r-eaction was relieved in the burnt wound by using emu oil. And shown by the histolo-gical analysis that the wound epithelization was facilitated in group C.The epidermis in emu oil treated wound was thick and the epidermal ridges were enlarged.The expression of PCNA in wound tissues specimens in group C was higher than that in the other groups (Factorial analysis? F—962.40, P<0.01 ),and was decreased obviously over time (Factorial analysis, F=95.63, P<0.01) .The negative cells of K10 staining in wound tissues specimens in group C were bigger in size and larger in number and localized at the base of epidermis than that in the other groups at the 10th, 14th day.lt was found that there were some negative cells in epidermis treated with emu oil at the 10th, 14thday and absent from the others.Immunohistochemical staining from K14 showed that the positive cells at epidermis in wound tissues specimens in group C were more than that in the other groups at the 10th, 14thday.The cell positive rate of EGF in wound tissues specimens in group C was higher than that in other groups at the 5th , 10th, 14th day (Factorial analysis, F= 1219.68, P<0.01) .It was the biggest at the 10th day in group C.CONCLUSIONEmu oil can accelerate wound healing; Emu oil can speed the proliferation of repair cells in wound tissues;Emu oil can hasten mitogenic and differentiation of skinstem cells ;Emu oil can accelerate the expression of EGF in the burnt wound.