RESUMO
OBJECTIVE: To determine the effects of naoyian (NYA) serum on the expression of vascular endothelial growth factor (VEGF) protein in cultured rat cerebral microvascular endothelial cell (RCMEC) with hypoxia. METHODS: NYA serum was separated from rat heart which had been filled stomach with NYA successively for 3 days. The rat cerebral microvascular endothelial cells were taken from the Sprageu-Dawley rat brain at postborn 7 days. The rat cerebral microvascular endothelial cells were incubated at anaerobic incubator to establish the hypoxia models. The vigo of RCMEC was determined by MTT. The level of expression of VEGF protein was measured by cell immunohistochemistry and Western blot. RESULTS: The OD value of NYA serum group was higher than the control groups after hypoxia for 18 hours. VEGF protein was increased by hypoxia in cerebral microvascular endothelial cells (P < 0.05). The content of VEGF protein in NYA serum containing medium was more significantly elevated than those cultured in other control media (P < 0.01). CONCLUSION: VEGF protein was induced by hypoxia in rat cerebral microvascular endothelial cells, and NYA could upregulate the expression of VEGF protein, which may be one of the protection mechanisms for cerebral microvascular endothelial cells.
Assuntos
Córtex Cerebral/irrigação sanguínea , Medicamentos de Ervas Chinesas/farmacologia , Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Animais Recém-Nascidos , Capilares/citologia , Hipóxia Celular , Células Cultivadas , Endotélio Vascular/citologia , Feminino , Masculino , Ratos , Ratos Sprague-Dawley , Soro , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
Bcl-xL is a well characterized death-suppressing molecule of the Bcl-2 family. Bcl-xL is expressed in embryonic and adult neurons of the CNS and may play a critical role in preventing neuronal apoptosis that occurs during brain development or results from diverse pathologic stimuli, including cerebral ischemia. In this study, we used a novel approach to study the potential neuroprotective effect of Bcl-xL as a therapeutic agent in the murine model of focal ischemia/reperfusion. We created a Bcl-xL fusion protein, designated as PTD-HA-Bcl-xL, which contains the protein transduction domain (PTD) derived from the human immunodeficiency TAT protein. We demonstrated that this fusion protein is highly efficient in transducing into primary neurons in cultures and potently inhibited staurosporin-induced neuronal apoptosis. Furthermore, intraperitoneal injection of PTD-HA-Bcl-xL into mice resulted in robust protein transduction in neurons in various brain regions within 1-2 hr, and decreased cerebral infarction (up to approximately 40%) in a dose-dependent manner, as determined at 3 d after 90 min of focal ischemia. PTD-HA-Bcl-xL was effective even when it was administered after the completion of ischemia (up to 45 min), and the protective effect was independent of the changes in cerebral blood flow or other physiological parameters. Finally, as shown by immunohistochemistry, Western blotting, and substrate-cleavage assays, PTD-HA-Bcl-xL attenuated ischemia-induced caspase-3 activation in ischemic neurons. These results thus confirm the neuroprotective effect of Bcl-xL against ischemic brain injury and provide the first evidence that the PTD can be used to efficiently transduce a biologically active neuroprotectant in experimental cerebral ischemia.