RESUMO
BACKGROUND: Astragalus genus includes most of the common, historical herbal medicines that have various applications in Asian countries. However, clinical data and mechanistic insights into their actions are still lacking. PURPOSE: In this study, we aimed to examine the effects of astragalosides on wound healing in vitro and in vivo, as well as the underlying mechanisms of these actions. METHODS: The wound healing activity of astragalosides was investigated in human HaCaT keratinocytes, human dermal fibroblast (HDF) cells, and murine models of wound healing. RESULTS: All eight astragalosides studied enhanced epidermal growth factor receptor (EGFR) activity in HaCaT cells. Among them, astragaloside VI (AS-VI) showed the strongest EGFR activation. Consistently, AS-VI and cycloastragenol-6-O-beta-D-glucoside (CMG), which is the major metabolite of astragalosides, enhanced extracellular signal-regulated kinase (ERK) activity in a concentration-dependent manner. In agreement, both compounds induced EGFR-dependent cell proliferation and migration in HaCaT and HDF cells. In addition, we showed that AS-VI and CMG accelerated the healing of both sterile and infected wounds in vivo. These effects were associated with increased angiogenesis in the scar tissue. CONCLUSION: AS-VI and CMG increased the proliferation and migration of skin cells via activation of the EGFR/ERK signalling pathway, resulting in the improvement of wound healing in vitro and in vivo. These findings indicate the therapeutic potential of AS-VI and CMG to accelerate wound healing; additionally, they suggest the mechanistic basis of this activity.
Assuntos
Glucosídeos/farmacologia , Saponinas/farmacologia , Triterpenos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Astrágalo/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Receptores ErbB/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Pele/citologia , Pele/efeitos dos fármacosRESUMO
OBJECTIVE: To observe the effectiveness of MEBO in the treatment of burn patients with burn area over 50% TBSA. METHODS: Two hundred and ninety-eight patients hospitalized in our hospital from May of 1991 to December of 2003 with burn area over 50% TBSA, who had MEBO treatment before hospitalization, were enrolled in the study as the experiment (E) group. Another group of 300 burn patients with burn area over 50% TBSA that treated with SD-Ag cream were enrolled in the study as the control (C) group. Bacterial culture results, major changes in injury and mortality were compared between the two groups. RESULTS: There were 1 506 bacteria strains isolated from wounds in E group, and 9 main changes in injury (1679 cases) occurred with 20.8% mortality in this group. There were 353 bacteria strains isolated, with occurrence of 9 changes in injury (518 cases) and 4.7% mortality in the SD-Ag group. CONCLUSION: MEBO is much less effective for the treatment of the burn patients with large burn area compared with SD-Ag cream treatment.