PURPOSE: Evaluation of the rheological, biological and therapeutic properties of a new topical formulation consisting of chitosan gel containing 1% silver sulfadiazine, as an alternative for the treatment of burn wounds. METHODS: An experimental study was done with 21 Wistar rats divided into three groups. Group I was treated with chitosan gel without the antimicrobial, group II was treated with chitosan gel with 1% silver sulfadiazine and group III was treated with commercially available 1% silver sulfadiazine cream. RESULTS: Due to its pseudoplastic characteristic and good bioadhesiveness, the chitosan gels showed a satisfactory retention time over the wounds. No statistical difference was found in the amount of drug released from the chitosan gel and commercially available cream, as well as in the healing time among the groups. Wounds treated with chitosan gel with silver sulfadiazine showed a higher fibroblast production and a better angiogenesis than in the other groups, which are important parameters on the evolution of the healing process. CONCLUSION: The topical use of chitosan gel in association with silver sulfadiazine ameliorated the neovascularization and inflammatory reaction in burn wounds. This new formulation showed advantageous rheological properties and efficient release of the drug.

OBJECTIVES: Seeds are excellent sources of proteinase inhibitors, some of which may have satietogenic and slimming actions. We evaluated the effect of a trypsin inhibitor from Tamarindus indica L. seeds on weight gain, food consumption and cholecystokinin levels in Wistar rats. METHODS: A trypsin inhibitor from Tamarindus was isolated using ammonium sulfate (30-60%) following precipitation with acetone and was further isolated with Trypsin-Sepharose affinity chromatography. Analyses were conducted to assess the in vivo digestibility, food intake, body weight evolution and cholecystokinin levels in Wistar rats. Histological analyses of organs and biochemical analyses of sera were performed. RESULTS: The trypsin inhibitor from Tamarindus reduced food consumption, thereby reducing weight gain. The in vivo true digestibility was not significantly different between the control and Tamarindus trypsin inhibitor-treated groups. The trypsin inhibitor from Tamarindus did not cause alterations in biochemical parameters or liver, stomach, intestine or pancreas histology. Rats treated with the trypsin inhibitor showed significantly elevated cholecystokinin levels compared with animals receiving casein or water. CONCLUSION: The results indicate that the isolated trypsin inhibitor from Tamarindus reduces weight gain by reducing food consumption, an effect that may be mediated by increased cholecystokinin. Thus, the potential use of this trypsin inhibitor in obesity prevention and/or treatment should be evaluated.