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Molecular Biology Reports

, Volume 40, Issue 1, pp 51–58 | Cite as

Acylated ghrelin protects hippocampal neurons in pilocarpine-induced seizures of immature rats by inhibiting cell apoptosis

  • Ruiyun Zhang
  • Guanglu Yang
  • Qingyi Wang
  • Feng Guo
  • Hua Wang
Article

Abstract

Ghrelin has two major molecular forms, acylated ghrelin (AG) and unacylated ghrelin (UAG). Only AG to bind growth hormone secretagogue receptor 1a (GHSR-1a) has central endocrine activities. An antiapoptotic effect of AG in cortical neuronal cells has recently been reported. However, whether there is a neuroprotective effect of AG in hippocampal neurons of pilocarpine-induced seizures in rats, is still unknown. Therefore, in the present study, the underlying mechanism of AG on lithium-pilocarpine-induced excitotoxicity was examined in the hippocampus of rat. The results showed that AG inhibited pilocarpine-induced apoptosis. Exposure of rats to the receptor-specific antagonist D-Lys-3-GHRH-6 abolished the protective effects of AG against epilepsy. Administration of AG resulted in increased expression of phosphor-Akt in status epilepticus model in rats, which was accompanied with the attenuation of hippocampal cell death. Furthermore, administration of AG resulted in decreased expression of phosphor-JNK in pyramidal neurons of hippocampus after status epilepsy, which was also accompanied with the attenuation of hippocampal cell death, too. In addition, AG increased the Bcl-2/Bax ratio and inhibited caspase-3 activation. The data indicate that AG can function as a neuroprotective agent that inhibits apoptotic pathways. These effects may be mediated via activation of the PI3K/Akt pathway.

Keywords

Acylated ghrelin Apoptosis Neuroprotective effect Epilepsy Hippocampus Pilocarpine 

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Copyright information

© Springer Science+Business Media Dordrecht 2012

Authors and Affiliations

  • Ruiyun Zhang
    • 1
    • 2
  • Guanglu Yang
    • 1
  • Qingyi Wang
    • 3
  • Feng Guo
    • 4
  • Hua Wang
    • 1
  1. 1.Department of PediatricsShengjing Hospital, China Medical UniversityShenyangChina
  2. 2.Department of PediatricsHongqi Hospital, Mudanjiang Medical UniversityMudanjiangChina
  3. 3.Department of OrthopaedicsHongqi Hospital, Mudanjiang Medical UniversityMudanjiangChina
  4. 4.Department of Pharmaceutical ToxicologySchool of Pharmaceutical Science, China Medical UniversityShenyangChina

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