ABSTRACT
The purpose of this study was to investigate the effect of inhibition of calpain on retinal ganglion cell-5 (RGC-5) necroptosis following oxygen glucose deprivation (OGD). RGC-5 cells were cultured in Dulbecco's-modified essential medium and necroptosis was induced by 8-h OGD. PI staining and flow cytometry were performed to detect RGC-5 necrosis. The calpain expression was detected by Western blotting and immunofluorescence staining. The calpain activity was tested by activity detection kit. Flow cytometry was used to detect the effect of calpain on RGC-5 necroptosis following OGD with or without N-acetyl-leucyl-leucyl-norleucinal (ALLN) pre-treatment. Western blot was used to detect the protein level of truncated apoptosis inducing factor (tAIF) in RGC-5 cells following OGD. The results showed that there was an up-regulation of the calpain expression and activity following OGD. Upon adding ALLN, the calpain activity was inhibited and tAIF was reduced following OGD along with the decreased number of RGC-5 necroptosis. In conclusion, calpain was involved in OGD-induced RGC-5 necroptosis with the increased expression of its downstream molecule tAIF.
Subject(s)
Animals , Humans , Mice , Apoptosis Inducing Factor , Genetics , Calpain , Genetics , Gene Expression Regulation , Glucose , Metabolism , Leupeptins , Oxygen , Metabolism , Retinal Ganglion Cells , Metabolism , Pathology , Retinal Necrosis Syndrome, Acute , Genetics , PathologyABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects and mechanism of qi-tonifying and stasis-eliminating (QTSE) therapy on the expression of vascular endothelial growth factor (VEGF) and its receptors Flt-1 and Flk-1 in the brains of intracerebral hemorrhagic (model) rats.</p><p><b>METHODS</b>One hundred and eighty Sprague-Dawley rats were randomly divided into six groups: the normal group (n=5), the sham-operative (SO) group (n=35), the model group (n=35), the QTSE group (n=35), the QT group (n=35) and the SE group (n=35). All the rats except those in the normal group and SO group were established into an intracerebral hemorrhage(ICH) model by intracerebral injection of collagenase type VII and the latter three were orally administered with Buyang Huanwu Decoction (a classical recipe for QTSE) or with some of its components for qi-tonification and for stasis-elimination, respectively. To the other three groups, normal saline solutions were given instead. Behavioral tests were carried out in the animals randomly chosen from each group on days 1, 2, 4, 7, 14, 21 and 28 after modeling. The expressions of VEGF, Flk-1 and Flt-1 were determined by immunohistochemistry and the number of vascular segments with positive expression in the injured brain area of the rats was calculated.</p><p><b>RESULTS</b>From day 7 onwards, the asymmetric forelimb use rate in the QTSE group recovered more significantly than that in the other model groups. In the model group, the expressions of VEGF, Flk-1 and Flt-1 appeared on day 1 and reached a peak on day 21, then weakened gradually. In the QTSE group, as compared with the other model groups, a higher level of VEGF expression was shown from day 7 (P<0.01) and a higher level of Flt-1 expression was shown from the 7th day to the 21st day (P<0.01).</p><p><b>CONCLUSION</b>QTSE therapy can up-regulate the expressions of VEGF and its receptors (Flk-1 and Flt-1) and improve the recovery of kinetic function in the ICH rats, which may be correlated with its action in modulating vascular regeneration to promote the reconstruction of microvascular networks in the damaged areas.</p>
Subject(s)
Animals , Female , Male , Rats , Behavior, Animal , Brain , Metabolism , Cerebral Hemorrhage , Drug Therapy , Metabolism , Forelimb , Medicine, Chinese Traditional , Methods , Phytotherapy , Methods , Qi , Rats, Sprague-Dawley , Vascular Endothelial Growth Factor A , Metabolism , Vascular Endothelial Growth Factor Receptor-1 , Metabolism , Vascular Endothelial Growth Factor Receptor-2 , MetabolismABSTRACT
OBJECTIVE@#To explore the effect of precursor of brain-derived neurotrophic factor (proBDNF) on cultured hippocampal neuron and its intracellular mechanism.@*METHODS@#The hippocampal neurons were dissociated from E18 rats and cultured in neurobasal medium, and then the cells were treated with proBDNF, preBDNF(propeptide of proBDNF) and proBDNF antiserum,respectively. Thirty minutes, 1 hour or 48 hours later, the cells were stained with Nissl solution, and the immunocytochemistry methods of ELK-p (Ets domain protein), ErK2(extracellular signal regulated kinase) and c-fos were performed.@*RESULTS@#The expressions of ELK-p, ErK and c-fos were significantly upregulated in the cultured hippocampal neurons after they were treated with proBDNF protein,and the immuno-positive staining was also obvious in some nuclei. While the endogenous proBDNF was neutralized by proBDNF antiserum treatment, the expressions of ELK-p, ErK and c-fos were downregulated and many cells showed swelling and vasoculation. The immunoreactivity in preBDNF treated cells was similar to that in normal cultured cells.@*CONCLUSION@#proBDNF plays an important role in sustaining the hippocampal neuron survival through upregulating the ELK and ErK pathways.