Use of a Model of a Blood-Induced Bruise for the Evaluation of Formulations on Bruising

Esthetic treatments can induce swelling and bruises. Thus, a treatment that would prevent or hasten the resolution of bruising should be very useful. Generally, the regression of bruising was conducted with patients or animals models. So we decided firstly to develop an ex vivo model in order to test antibruising properties of topical formulations and secondly to evaluate a curative effect of a cream (mixture of arnica extract and apigenin) in comparison with a positive control (vulnerary cream) and also to estimate the preventive interest of this cream. The results showed that the injection of 25 μl of blood into the dermis of skin fragments was sufficient to create a model of induced-bruise. The duration of 24 hours was chosen to compare the effects of actives on the decrease in the size of the bruise. Joint effects of a pretreatment and a treatment of a mixture of arnica extract and apigenin decreased significantly the area of bruising compared to the treatment group, the control group and the positive control group. Many topical products claim to improve bruising on their package label. Our model can demonstrate their efficacy and determinate the best topical antibruising formulation. The mechanism involved in anti-inflammatory activity of active compounds of topical formulations is often not fully understood. Our blood-induced model may bring some responses through the study of mediators of the inflammation.