Expression of Bcl-2 and Bad in hippocampus of status epileptic rats and molecular mechanism of intervened recombinant human erythropoietin

Abstract

Injury of hippocampal neurons in status epilepticus (SE) SD rats kindled by pentylenetetrazol (PTZ) were studied, and the changes of apoptosis neurons, protein expression of Bad and Bcl-2 alone and combined application of phosphatidyl inositol 3-kinase (PI3K) inhibitor LY294002 and recombinant human erythropoietin (rHuEpo) were evaluated for the possible mechanisms of rHuEpo. The SE rats kindled by the PTZ were randomly divided into normal control group [normal saline (NS)], model group (PTZ + NS), rHuEpo treated group (PTZ + rHuEpo), LY294002 treated group (PTZ + LY294002 + rHuEpo) and LY294002 control group (rHuEpo + PTZ + DMSO). Apoptosis of hippocampal neurons was detected by TUNEL method; expression of phosphorylation protein kinase B (p-PKB/p-Akt), Bcl-2 and Bad were detected by immunohistochemistry; the expression of Bcl-2 mRNA, Bad mRNA in hippocampal neurons of rats were detected through reverse transcription polymerase chain reaction (RT-PCR); the expression of Akt, p-Akt and Bcl-2, Bad protein in hippocampal neurons of rats were detected by western blotting. The amount of apoptotic neurons was less in the rHuEpo treated group and the LY294002 control group than in the LY294002 treated group (P<0.05). The expression of p-Akt protein and Bcl-2 protein increased while the Bad protein decreased significantly in the rHuEpo treated group and the LY294002 control group compared with the LY294002 treated group (P<0.05). The expression of Bad protein and Bad mRNA in hippocampus increased while the p-Akt, Bcl-2, Bcl-2 mRNA decreased significantly in the LY294002 treated group compared with the rHuEpo treated group (P<0.05). The PI3K/Akt signaling pathway is one of the pathways of rHuEpo neuroprotective effects and was confirmed from both the of positive and negative aspects. rHuEpo regulates the expression of mitochondrial apoptotic pathway related factors Bad and Bcl-2 to inhibit apoptosis and promotes neuronal survival.

The Neuroprotective Effect of Astaxanthin on Pilocarpine-Induced Status Epilepticus in Rats

“…TUNEL staining directly detects apoptotic cells, and the Bcl-2 protein family regulates apoptosis by controlling the release of mitochondrial apoptosis factors, cytochrome c, and apoptosis induction factors, which activate downstream executive reactions, including caspases (Zamzami and Kroemer, 2001). Previous studies demonstrated that caspase-3 was significantly activated in the brain of rats with epilepsy, cleaved caspase-3 significantly increased, the pro-apoptotic protein Bax increased, and the anti-apoptotic protein Bcl-2 decreased (Akcali et al, 2005; Yu et al, 2018). Our results confirmed these changes, and AST reversed these changes.…”

“…However, the underlying molecular mechanisms are yet completely understood. Previous studies reported that the neuronal death in the brain after SE mainly includes apoptosis and necrosis, and apoptosis is an important factor (Yu et al, 2018). Our study showed that neuronal apoptosis in the hippocampal CA1 region was obvious in SE rats using TUNEL staining, which is consistent with previous studies (Kotloski et al, 2002).…”

The role of erythropoietin in the regulation of cardiac tolerance to impact of ischemia and reperfusion

“…Активация эритропоэтином Akt и PI3K была подтверждена в ряде исследований [15,[32][33][34][35][36]. Дополнительно, путем стимуляции PI3K, эритропоэтин демонстрировал противовоспалительный эффект [37].…”