title: Nupr1/Chop signal axis is involved in mitochondrion-related endothelial cell apoptosis induced by methamphetamine.
abstract: Methamphetamine (METH) abuse has been a serious global public health problem for decades. Previous studies have shown that METH causes detrimental effects on the nervous and cardiovascular systems. METH-induced cardiovascular toxicity has been, in part, attributed to its destructive effect on vascular endothelial cells. However, the underlying mechanism of METH-caused endothelium disruption has not been investigated systematically. In this study, we identified a novel pathway involved in endothelial cell apoptosis induced by METH. We demonstrated that exposure to METH caused mitochondrial apoptosis in human umbilical vein endothelial cells and rat cardiac microvascular endothelial cells in vitro as well as in rat cardiac endothelial cells in vivo. We found that METH mediated endothelial cell apoptosis through Nupr1-Chop/P53-PUMA/Beclin1 signaling pathway. Specifically, METH exposure increased the expression of Nupr1, Chop, P53 and PUMA. Elevated p53 expression raised up PUMA expression, which initiated mitochondrial apoptosis by downregulating antiapoptotic Bcl-2, followed by upregulation of proapoptotic Bax, resulting in translocation of cytochrome c (cyto c), an apoptogenic factor, from the mitochondria to cytoplasm and activation of caspase-dependent pathways. Interestingly, increased Beclin1, upregulated by Chop, formed a ternary complex with Bcl-2, thereby decreasing the dissociative Bcl-2. As a result, the ratio of dissociative Bcl-2 to Bax was also significantly decreased, which led to translocation of cyto c and initiated more drastic apoptosis. These findings were supported by data showing METH-induced apoptosis was significantly inhibited by silencing Nupr1, Chop or P53, or by PUMA or Beclin1 knockdown. Based on the present data, a novel mechanistic model of METH-induced endothelial cell toxicity is proposed. Collectively, these results highlight that the Nupr1-Chop/P53-PUMA/Beclin1 pathway is essential for mitochondrion-related METH-induced endothelial cell apoptosis and may be a potential therapeutic target for METH-caused cardiovascular toxicity. Future studies using knockout animal models are warranted to substantiate the present findings.
authors.affiliation: Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China.
authors.forename: D
authors.initials: D
authors.lastname: Cai
authors.affiliation: Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China.
authors.forename: E
authors.initials: E
authors.lastname: Huang
authors.affiliation: Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China.
authors.forename: B
authors.initials: B
authors.lastname: Luo
authors.affiliation: Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Key Lab of Forensic Pathology, Guangdong Provincial Public Security Department, Guangzhou 510050, China.
authors.forename: F
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Guangzhou Forensic Science Institute, Guangzhou 510030, China.
authors.forename: C
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Anatomy and Physiology, College of Veterinary Medicine, Institute of Computational Comparative Medicine, Kansas State University, Manhattan, KS 66506, USA.
authors.forename: Z
authors.identifier: http://orcid.org/0000-0002-8731-8366
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China.
authors.forename: W-B
authors.initials: WB
authors.lastname: Xie
authors.affiliation: Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China.
authors.forename: H
authors.initials: H
authors.lastname: Wang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D051792:Basic Helix-Loop-Helix Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000071186:Beclin-1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D000697:Central Nervous System Stimulants / Q000633:toxicity; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008694:Methamphetamine / Q000633:toxicity*; D008928:Mitochondria / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects; D051742:Transcription Factor CHOP / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; D051792:Basic Helix-Loop-Helix Proteins; D000071186:Beclin-1; D000697:Central Nervous System Stimulants; D008694:Methamphetamine; D009363:Neoplasm Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051742:Transcription Factor CHOP; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; C533952:Bbc3 protein, rat; C497251:Ddit3 protein, rat; C109741:Nupr1 protein, rat