Issue Archive

Humanin protects neurons against apoptosis induced by Aβ31-35 through suppression of intrinsic pathway

LI Ling-Min, ZHANG Yu, QIAO Jian-Tian, ZHANG Ce

Department of Pathology； Department of Physiology, Shanxi Medical University, Taiyuan 030001, China

Abstract

The present study aimed to investigate the effects of humanin (HN) on primary cortical neuronal apoptosis induced by Aβ31-35, and explore the potential mechanisms. Cultured cortical neurons were pretreated with different concentrations of HN (5, 10, 20 μmol/L) fordifferent time period (0, 8 and 16 h) respectively, and then exposed to Aβ31-35 (25 μmol/L) for additional 24 h and the neuronalapoptosis was examined by morphological analysis, flow cytometric assays and TUNEL staining. Caspase activities were measuredusing a spectrophotometer. Bax expression was measured by Western blot. The results were as follows. (1) Pretreatment with HN (20μmol/L) for 16 h significantly prevented Aβ31-35-induced apoptosis in cortical neurons; (2) HN significantly decreased Aβ31-35-inducedelevation of caspase-3 and -9 activities; (3) HN suppressed Aβ31-35-induced translocation of Bax from the cytosol to mitochondria, buthad no effect on overall Bax expression. In conclusions, HN attenuated Aβ31-35-induced cortical neuronal apoptosis by blocking intrinsiccaspase-dependent apoptotic pathways.

Key words: Aβ31-35; humanin; apoptosis; neuroprotection; intrinsic pathways

Received: 2009-12-03　　Accepted: 2010-01-21

Corresponding author: 张策　　E-mail: cezh2002@yahoo.com

Citing This Article：

LI Ling-Min, ZHANG Yu, QIAO Jian-Tian, ZHANG Ce. Humanin protects neurons against apoptosis induced by Aβ31-35 through suppression of intrinsic pathway. Acta Physiol Sin 2010; 62 (2): 93-100 (in Chinese with English abstract).