Effect of carbamylated erythropoietin on neuronal apoptosis in fetal rats during intrauterine hypoxic-ischemic encephalopathy

Abstract

Background Hypoxic-ischemic encephalopathy (HIE) is a common disease that occurs during the perinatal period. The primary cause of neonatal HIE is related to fetal intrauterine anoxia. Carbamylated erythropoietin (CEPO), a derivative of erythropoietin (EPO), does not exert any erythropoietic effect; however, the neuroprotective effects resemble those of EPO. Previous studies have shown the potential benefits of CEPO on the central nervous system. The present study aimed to investigate the role of CEPO in neuronal apoptosis during intrauterine HIE and the underlying mechanisms. Results To validate our hypothesis, we established an intrauterine HIE model by occluding the bilateral utero-ovarian arteries of pregnant Sprague–Dawley rats. Compared to the I/R group, neuronal apoptosis in the CEPO group was significantly lower at 4, 12, 24, and 48 h (P < 0.05). CEPO significantly inhibited CC3 expression (P < 0.05) during the early-stages after ischemia–reperfusion (0.5, 4, 8, 12 and 24 h), upregulated Bcl-2 expression, and downregulated Bax expression at 4, 8, 12, and 24 h (P < 0.05). Conclusions Carbamylated erythropoietin pretreatment inhibited the expression of proapoptotic protein CC3 in brain and regulated the Bcl-2/Bax ratio, resulting in reduced neuronal apoptosis and thus resulting in a protective effect on intrauterine HIE.

Overexpression of miR-146a inhibits the apoptosis of hippocampal neurons of rats with cerebral hemorrhage by regulating autophagy

“…24,25 Bcl-2 and Bax are major regulators of apoptosis, which play a crucial role in the regulation of apoptosis in brain injury diseases, including ICH 25 and hypoxic ischemic reperfusion (I/R). 26 As a pro-apoptotic member of the Bcl-2 family, Bax translocates from the cytoplasm to the mitochondrial outer membrane, which results in caspase 3 activation. 26 When the ratio of Bcl-2/Bax is decreased, apoptosis is induced, while the opposite occurs when it is increased.…”

The analytical approach for detection of carbamylated erythropoietin for doping control purposes

“…The literature data show that electrophoretic mobility of CEPO is similar to rhEPO when denaturing SDS-containing gels are used. 12 CEPO mobility is higher than rhEPO in native gels, which can be explained by the increase in the net electric charge of the molecule. 13 (Figure 3b).…”

“…This protocol was also used in other studies that showed complete conversion of EPO to CEPO (Figure 1). 7,8,12 Surprisingly, the SAR-PAGE analysis of the CEPO product showed as broad band with an apparent mass slightly lower than rhEPO (Figure 2), even though nine carbamyl moieties were supposed to be bounded to the eight lysins and N-terminus. This should slightly (by 387 Da) increase the molecular mass of rhEPO, which should not be enough to see the difference when using the gel electrophoretic technique denaturating 10% polyacrylamide gel.…”

Pathogenic substantiation of application of erythropoietin modified forms and peptide analogues as cytotprotectors

“…Профилактическое введение крысам СЕРО приводит к ингибированию экспрессии про-апоптогенного белка CC3 в мозге и регулирует соотношение Bcl-2/Bax, что в конечном счете ограничивает апоптоз нейронов и характеризуется защитным эффектом на модели внутриматочной гипоксии-ишемии [45].…”

“…Как и Эпо, Epotris проникает через ГЭБ, ослабляет нейротоксические эффекты каината, однако не стимулирует эритропоэз. В литературе присутствует информация об исследованиях пептидного аналога Эпо Epopeptide-ab, представляющего собой последовательность из 17 аминокислот (AEHCSLNENITVPDTKV), соответствующую области AB-петли Эпо (последовательность аминокислот [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47], который обладает активностью, сходной с целым белком. Нейропротективный эффект Epopeptide-ab подтвержден в опытах in vivo на модели ишемического повреждения нейронов [59].…”