Objective: To investigate the protective mechanism of geniposide, baicalin and berberine on hypoxia and reoxygenation injury in cultured rat cerebral microvascular endothelial cells.
Method: A model of four hours hypoxia and twelve hours reoxygenation injury in rat cerebral microvascular endothelial cells in vitro was established. The injured cells were treated with geniposide (0.128, 0.064, 0.032 mmol x L(-1)), baicalin (0.028, 0.014, 0.007 mmol L(-1)) and berberine (0.024, 0.012, 0.006 mmol L(-1)), respectively. The immunocytochemical method and techniques of image quantitative analysis were used to detect the mean optical density and mean area in order to match the protein expression of VCAM-1. The method of RT-PCR was adopted to observe and match the mRNA expression of VCAM-1.
Result: As compared with the normal group, the mean optical density, the mean area and the mRNA expression of VCAM-1 of model group were significant increased (P < 0.01, P < 0.01, P < 0.01). As compared with the model group, both the mean optical density and the mean area of all treated groups were decreased, and there was significant difference between them (P < 0.01, P < 0.01). As compared with normal group, the mean optical density of baicalin (0.007 mmol x L(-1)) and berberine (0.012, 0.006 mmol x L(-1)) were significant decreased (P < 0.05, P < 0.01, P < 0.01), but there was no significant difference between the other groups and the normal group. As compared with normal group, the mean area of baicalin (0.0014 mmol x L(-1)) was significant decreased (P < 0.05), but there was significant difference between the other groups and the normal group. The mRNA expression of all treated groups was not only lower than that of the model group but also higher than that of the normal group (P < 0.05, P < 0.05).
Conclusion: The results suggest that geniposide, baicalin and berberine, which are effective compositions of huanglian jiedu decoting, can protect hypoxia-reoxygenation injuried rat cerebral microvascular endothelial cells. One of the protected mechanisms is that they can inhibit the expression of VCAM-1.