title: MicroRNA-873 Inhibits Morphine-Induced Macrophage Apoptosis by Elevating A20 Expression.
abstract: OBJECTIVE
  To study the role of microRNA-873 (miR-873) in suppressing morphine-induced macrophage apoptosis and morphine dependence, and to identify molecular targets within the miR-873 pathway for the treatment of immune suppression and morphine addiction.
  
  
  METHODS
  As morphine elevates TLR9 expression and induces TLR9-mediated apoptosis, we used TLR9 knockout Balb/C mice to study TLR9-independent effects of miR-873 on morphine-induced macrophage apoptosis. Forty TLR9-knockout mice were randomly and equally assigned to morphine group and control group. Following the administration of morphine, miR-873 mimics or miR negative control was injected into mice in each group. Using freshly isolated macrophages from mice and RAW264.7 murine macrophage cell line, miR-873 level was determined by qRT-PCR and morphine induced apoptosis was measured by TUNEL assays. Western blotting was used to detect and quantify the expression level of A20, a protein that negatively regulates inflammation and TNF-induced apoptosis.
  
  
  RESULTS
  qRT-PCR analysis revealed a markedly lower expression of miR-873 in freshly isolated peritoneal macrophages, liver tissue and spleen tissue in the morphine group compared with the corresponding tissues in the control group. TUNEL assays showed that the apoptosis rates in the morphine groups treated with miR-873 mimics was markedly lower than their respective control groups. Western blotting results showed that A20 expression level was sharply elevated in the experimental groups treated with miR-873 mimics than the negative and blank control groups.
  
  
  CONCLUSIONS
  Our results show that miR-873 elevates A20 levels and inhibits morphine-induced macrophage apoptosis.
authors.affiliation: Department of Anesthesiology, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College, Qingdao University, Yantai.
authors.forename: Ming-Chuan
authors.initials: MC
authors.lastname: Li
authors.affiliation: Department of Anesthesiology, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College, Qingdao University, Yantai.
authors.forename: Jian-Hong
authors.initials: JH
authors.lastname: Yu
authors.affiliation: Department of Anesthesiology, People's Hospital of Rizhao, Rizhao, P.R. China.
authors.forename: Shou-Shui
authors.initials: SS
authors.lastname: Yu
authors.affiliation: Department of Anesthesiology, Yantai Yuhuangding Hospital, Affiliated Hospital of Medical College, Qingdao University, Yantai.
authors.forename: Yun-Yang
authors.initials: YY
authors.lastname: Chi
authors.affiliation: Department of Anesthesiology, Yantai University, Pharmacy College, Yantai, P.R. China.
authors.forename: Yong-Bing
authors.initials: YB
authors.lastname: Xiang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D002460:Cell Line; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D035683:MicroRNAs / Q000378:metabolism*; D009020:Morphine / Q000008:administration & dosage*; D000067996:RAW 264.7 Cells; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3; D015854:Up-Regulation / Q000502:physiology / Q000528:radiation effects
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; C000593791:MIRN873 microRNA, mouse; D035683:MicroRNAs; D009020:Morphine; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3; D003546:Cysteine Endopeptidases; C513261:Tnfaip3 protein, mouse
keywords: Immune Suppression; Macrophage Apoptosis; MicroRNA-873; Morphine; Morphine Addiction; Morphine Dependence; Real-Time Quantitative PCR; TUNEL Assays