Protective effect of Danhong injection on cerebral ischemia-reperfusion injury in rats

Ethnopharmacological relevance: Danhong injection (DH), a Chinese medical product, is used extensively for the treatment of cerebrovascular diseases such as acutely cerebral infarction in clinic. Aim of the study: To explore the protective effect and the relevant mechanisms of DH on cerebral ischemia-reperfusion (I/R) injury. Materials and methods: Cerebral I/R injury was induced through four-vessel occlusion (4-VO) or middle cerebral artery occlusion (MCAO). Adult male SD rats were randomly divided into six kinds of groups: normal control group, sham-operated group, I/R injury group, DH-treated groups at doses of 0.5 ml/kg, 1.0 ml/kg and 2.0 ml/kg. The effects of DH on murine neurological deficits and cerebral infarct volume, 6-keto-prostagladin F-1 alpha (6-keto-PGF(1 alpha)) level, malondialdehyde (MDA) level and superoxide dismutase (SOD) activity in brain tissue, as well as the activities of plasma tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) after I/R were evaluated. Moreover, the expressions of Bcl-2 and Box protein were detected by immunohistochemistry. Results: There was no significant difference between the control group and the sham-operated group based on the measurement indicators. Compared with the vehicle-treated group, rats treated with DH showed dose dependent reductions in brain infarction size, and improvement of neurological outcome. The level of 6-keto-PGF(1 alpha) and the activities of SOD and plasma t-PA were enhanced significantly, whereas the level of MDA and the activity of plasma PAI were declined significantly. The immunohistochemical staining results also revealed that the expression of Bcl-2 protein was up-regulated and that of Bax protein was down-regulated when exposed to DH. Conclusion: DH demonstrates a strong ameliorative effect on cerebral I/R damage in rats by its anticoagulant, antithrombotic, antifibrinolytic and antioxidant activities. Furthermore, suppressing apoptosis through regulating Bcl-2 and Bax protein expressions should be another potential mechanism by which DH exerts its neuroprotective function. (C) 2012 Elsevier Ireland Ltd. All rights reserved.