Protective Effect Of FFTSG On Deep Second Degree Scald And Its Mechanisms In Rats

Scalds/Burns is common and frequently-occurring disease in clinical, which is oneof the most common accidental injuries in the daily work and life. Variety of risk factorsthat cause scalds/burns, the severity depends on the scope and depth of the damagedtissue, which have a higher fatality rate, there is no specific treatment. Fu Fang TangShang Gao (FFTSG) adopts the secret prescription handed down from a famoustraditional Chinese medicine doctor, which is compound synthesis of traditional Chinesemedicine preparations. FFTSG will not only remove rot and promote muscle growth,but also promote the regeneration of tissue cells and epidermal cells. We observed theprotective effect of FFTSG on the model of deep second degree scald in rats, andexplored the possible mechanisms of wound healing, in order to provide sufficienttheoretical and experimental basis for its clinical application and development.. Themain results are as follows:1Effects of FFTSG on burn wound healing in rat model of deep second degreescaldThe model of deep second degree scald wound was established with an iron rodimmersed in boiling water. The wound was identified as deep second degree scaldwound.30min after scalded, the rats were divided into5groups as follows: threeconcentration of FFTSG treated groups（0.4，0.2，0.1g extract.g crude drug-1）, SRSSG（0.32g extract.g crude drug-1）was used as a positive group. The drugs wereadministered topically on the surface of scalded places respectively by0.5g, once a dayfor continuously for21days. The rats were bred separately. The wound tissues were taken at different times after scald to observe the effects of FFTSG on wounds healingrate, wound tissues water contents and histopathology.1.1Effect of FFTSG on wound healing rate in rat model of deep second degreescaldTranslucent paper converting weigh method was adopted to calculate the woundhealing rate at post scald24h,7d,14d,21d. The results showed that the woundhealing rate in FFTSG（0.4,0.2g extract.g crude drug-1）treated group increased at postburn7d after scald; the wound healing rate in FFTSG（0.4,0.2,0.1g extract.g crudedrug-1） treated group increased obviously at14d21d after scald. The resultsdemonstrated that FFTSG have a good protective effect on rat model of second degreescald, which could visibly promote wound healing up and presented a dose-effect,time-effect relationship.1.2Effect of FFTSG on wound tissues water contents in rat model of deep seconddegree scaldThe dry wet weigh method was applied to compute the wound tissues watercontents at24h,48h,7d,14d,21d after scald. The results showed that the woundtissues water contents in FFTSG（0.4g extract.g crude drug-1） treated group decreasedobviously at48h after scald and also further declined in medium and lowconcentration of FFTSG treated group at7d,14d,21d after scald.1.3Effect of FFTSG on histopathology in rat model of deep second degree scaldThe wound tissues were taken at days1,7,14and21d after scald, and wereexecuted paraffin slice. The tissue morphological change on pathology slice wasobserved after hematoxylin and eosin (HE) staining. The results showed thatperformance of the model group for the epidermal structure is incomplete, edema,necrosis and inflammatory exudation, epidermis covered part of the wound. Thenumbers of collagen fiber bundles and fibroblasts of the model group were less than treated group. Treated group performance for the basic integrity of the epidermalstructure, epidermis covered partial or entirely wound. The numbers of collagen fiberbundles and fibroblasts of the treated group were more than model group. The growth ofgranulation tissue and hair follicle tissue of the treated group were much better thanmodel group. The numbers of inflammation cell infiltrated of the treated group wereless than model group. With the time passing, treated group’s wound healing will getbetter.2The possible action mechanism of FFTSG on rat model of deep second degreescald2.1Effect of FFTSG on the levels of vascular endothelial growth factor(VEGF) inrat model of deep second degree scaldThe levels of VEGF of the wound tissue were determined by enzyme-linkedimmunosorbent assay (ELISA) at24h,48h,7d,14d, and21d after scald. The resultsshowed that the levels of VEGF in FFTSG（0.4,0.2g extract.g crude drug-1）treatedgroup’s obviously increased at14d after scald and also further increased in FFTSG（0.4,0.2,0.1g extract.g crude drug-1）treated groups at21d after scald. Suggesting themechanism of FFTSG on the wound healing is probably related to increase the levels ofVEGF of the wound tissue.2.2Effect of FFTSG on the microvascular density(MVD) in rat model of deepsecond degree scaldMicrovascular density of the wound tissue with factor Ⅷ immunohistochemistrystaining were determined at48h,7d,14d,21d after scald. The results showed thatMVD in FFTSG（0.4,0.2g extract.g crude drug-1） treated group’s MVD obviouslyincreased at7d after scald. Further increase also showed in FFTSG（0.4,0.2g extract.gcrude drug-1）treated groups at14d,21d after scald. Suggesting the mechanisms ofFFTSG on the wound healing is probably related to increase the wound tissue MVD. 2.3The antioxidation effect of FFTSG on rat model of deep second degree scaldUV spectrophotometer analysis technique was used to detect the content ofmalondialdehyde(MDA) and the activity of superoxide dismutase(SOD) in blood serumof the wound rats at24h,48h,7d after scald. The results showed that the content ofMDA in FFTSG（0.4,0.2g extract.g crude drug-1） treated group’s obviously decreasedat post burn48h and further decreased in drug treated groups at7d after scald. Theactivity of SOD in FFTSG（0.4,0.2g extract.g crude drug-1） treated group’s obviouslyincreased at48h and further increased in durg treated group’s at7d after scald. Theseevidences showed FFTSG have strong antioxidation effect and it may be anotherimportant mechanism of its pharmacodynamics.2.4Effect of FFTSG on the levels of tumor necrosis factor-a(TNF-a) andinterleukin-1(IL-1) in rat model of deep second degree scaldThe levels of TNF-a and IL-1in blood serum were determined by enzyme-linkedimmunosorbent assay (ELISA) at24h,48h after scald. The results showed that thelevels of TNF-a obviously decreased in drug treated group’s at24h,48h after scald.The levels of IL-1in FFTSG（0.4,0.2g extract.g crude drug-1） treated group’sobviously decreased at48h after scald. Suggesting the mechanisms of FFTSG on thewound healing is probably related to inhibit inflammatory factors releasing.Conclusion: FFTSG has good therapeutic effect on rat model of deep second degreescald, which could visibly promote the wound healing up, decrease the wound tissueswater contents, and improve the changes of histopathology. The mechanisms of FFTSGmight be related with increasing the amount of wound VEGF releasing, enhancing thewound micrangium formation, decreasing the content of MDA in blood serum,increasing the activity of SOD in blood serum, inhibiting inflammatory factors ofTNF-a and IL-1releasing.