Autophagy upregulation and apoptosis downregulation in DAHP and triptolide treated cerebral ischemia.
It has previously been demonstrated that ischemic stroke activates autophagy pathways; however, the mechanism remains unclear. The aim of this study is to further investigate the role that autophagy plays in cerebral ischemia. 2, 4-diamino-6-hydroxy-pyrimidine (DAHP), for its nitric oxide synthase (NOS) inhibiting neuroprotective effect, and triptolide (TP), for its anti-inflammatory property, were selected to administer pre middle cerebral artery occlusion (MCAO). The drugs were administered 12 hours prior to MCAO. Both magnetic resonance imaging (MRI) and 2, 3, 5-triphenyltetrazolium chloride (TTC) staining showed that the drugs reduce the area of infarction. Immunoblotting analysis revealed increases in Beclin-1 and myeloid cell leukelia-1(Mcl-1) in treated rats. This could be a contributing factor to the reduction in autophagy induced damage. Immunochemistry and western blot showed that mTOR expression in treated rats was marginally different 24 h after injury, and this could also be significant in the mechanism. Furthermore, terminal deoxynucleotidyl transferase- (TdT-) mediated dUTP nick end labeling (TUNEL) staining proved that the drugs are effective in reducing apoptosis. The upregulation of Beclin-1 and Mcl-1 and downregulation of Bcl-2, caspase-3, and the Bcl-2/Beclin-1 ratio infer that the neuroprotective effect of DAHP and TP act via the mediation of autophagy and apoptosis pathways.
Institute of Neuroscience, Zhejiang University School of Medicine, Hangzhou 310058, China.
Yang
Y
Yang
Institute of Neuroscience, Zhejiang University School of Medicine, Hangzhou 310058, China.
Keqiang
K
Gao
Department of Obstetrics and Gynecology, Hangzhou Red Cross Hospital, Hangzhou 310003, China.
Zhiying
Z
Hu
Institute of Neuroscience, Zhejiang University School of Medicine, Hangzhou 310058, China.
Weiyun
W
Li
Institute of Neuroscience, Zhejiang University School of Medicine, Hangzhou 310058, China.
Henry
H
Davies
Institute of Neuroscience, Zhejiang University School of Medicine, Hangzhou 310058, China.
Shucai
S
Ling
School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
John A
JA
Rudd
Institute of Neuroscience, Zhejiang University School of Medicine, Hangzhou 310058, China.
Marong
M
Fang
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001343:Autophagy / Q000235:genetics / Q000502:physiology*; D015153:Blotting, Western; D002545:Brain Ischemia / Q000188:drug therapy*; D004224:Diterpenes / Q000627:therapeutic use*; D004852:Epoxy Compounds / Q000627:therapeutic use; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D010616:Phenanthrenes / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013400:Sugar Acids / Q000627:therapeutic use*
C017182:5-dehydro-3-deoxy-D-arabino-heptulosonic acid-7-phosphate; D004224:Diterpenes; D004852:Epoxy Compounds; D010616:Phenanthrenes; D013400:Sugar Acids; C001899:triptolide