PMID- 27724964 OWN - NLM STAT- MEDLINE DCOM- 20171005 LR - 20220311 IS - 1742-2094 (Electronic) IS - 1742-2094 (Linking) VI - 13 IP - 1 DP - 2016 Oct 10 TI - Sinomenine activates astrocytic dopamine D2 receptors and alleviates neuroinflammatory injury via the CRYAB/STAT3 pathway after ischemic stroke in mice. PG - 263 LID - 263 AB - BACKGROUND: Astrocyte-mediated neuroinflammation plays a critical role in ischemic stroke-induced secondary cerebral injury. Previous studies have suggested that the dopamine D2 receptor (DRD2) acts as a key target in regulating the neuroinflammatory response. However, the underlying molecular mechanisms are still unknown, and effective DRD2 agonists are lacking. In the present study, we examined the anti-inflammatory and neuroprotective effects of sinomenine (Sino), a monomeric compound with potential immunoregulatory properties in nervous system. METHODS: TTC staining, apoptosis assay, evaluation of brain edema, and neurological assessment were performed in the middle cerebral artery occlusion (MCAO) mouse model. Primary astrocytes exposed to oxygen glucose deprivation (OGD) were used in the in vitro experiments. Quantitative PCR was applied to assess the levels of inflammatory cytokines. Multi-labeling immunofluorescence, Western blot, co-immunoprecipitation, and electrophoretic mobility shift assay (EMSA) were also used to investigate the molecular mechanisms underlying the Sino-mediated anti-inflammatory effects in vivo and in vitro. RESULTS: Sino remarkably attenuated the cerebral infarction and neuronal apoptosis, reduced the levels of inflammatory cytokines, and alleviated neurological deficiency in MCAO mice. Sino significantly inhibited astrocytic activation and STAT3 phosphorylation as well as increased DRD2 and alphaB-crystallin (CRYAB) expression after MCAO. In vitro, Sino blocked OGD-induced activation of STAT3 and generation of pro-inflammatory cytokines in primary astrocytes, and these effects were significantly abolished by either DRD2 or CRYAB knockdown. Additionally, Sino induced up-regulation and nuclear translocation of CRYAB in astrocytes and enhanced the interaction between CRYAB and STAT3, which further inhibited the activation and DNA-binding activity of STAT3. CONCLUSIONS: Our study demonstrates that Sino activates astrocytic DRD2 and thereby suppresses neuroinflammation via the CRYAB/STAT3 pathway, which sheds some light on a promising therapeutic strategy for ischemic stroke. FAU - Qiu, Jing AU - Qiu J AD - Department of Neurology, The General Hospital of Shenyang Military Region, Shenyang, Liaoning, 110016, People's Republic of China. FAU - Yan, Zhongjun AU - Yan Z AD - Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China. FAU - Tao, Kai AU - Tao K AD - Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China. FAU - Li, Yansong AU - Li Y AD - Department of Neurology, The 463rd Hospital of PLA, Shenyang, Liaoning, 110042, People's Republic of China. FAU - Li, Yuqian AU - Li Y AD - Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China. FAU - Li, Jingchen AU - Li J AD - Department of Neurosurgery, The General Hospital of Shenyang Military Region, Shenyang, Liaoning, 110016, People's Republic of China. FAU - Dong, Yushu AU - Dong Y AD - Department of Neurosurgery, The General Hospital of Shenyang Military Region, Shenyang, Liaoning, 110016, People's Republic of China. FAU - Feng, Dayun AU - Feng D AD - Department of Neurosurgery, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, 710038, People's Republic of China. dayunfmmu@163.com. FAU - Chen, Huisheng AU - Chen H AD - Department of Neurology, The General Hospital of Shenyang Military Region, Shenyang, Liaoning, 110016, People's Republic of China. chsshenyang@sina.cn. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20161010 PL - England TA - J Neuroinflammation JT - Journal of neuroinflammation JID - 101222974 RN - 0 (Antirheumatic Agents) RN - 0 (Cryab protein, mouse) RN - 0 (Morphinans) RN - 0 (Receptors, Dopamine D2) RN - 0 (STAT3 Transcription Factor) RN - 0 (alpha-Crystallin B Chain) RN - 63LT81K70N (sinomenine) SB - IM MH - Animals MH - Animals, Newborn MH - Antirheumatic Agents/pharmacology/therapeutic use MH - Astrocytes/*drug effects MH - Brain Edema/drug therapy/etiology MH - Cells, Cultured MH - Cerebral Infarction/drug therapy/etiology MH - Disease Models, Animal MH - *Encephalitis/drug therapy/etiology/pathology MH - Hypoxia/drug therapy MH - Infarction, Middle Cerebral Artery/*complications MH - Mice MH - Mice, Inbred C57BL MH - Morphinans/*pharmacology/*therapeutic use MH - Nervous System Diseases/drug therapy/etiology MH - RNA Interference/physiology MH - Receptors, Dopamine D2/*metabolism MH - STAT3 Transcription Factor/metabolism MH - Signal Transduction/*drug effects MH - alpha-Crystallin B Chain/metabolism PMC - PMC5057372 OTO - NOTNLM OT - Astrocyte OT - Dopamine D2 receptor (DRD2) OT - Ischemic stroke OT - Neuroinflammation OT - Sinomenine EDAT- 2016/10/12 06:00 MHDA- 2017/10/06 06:00 PMCR- 2016/10/10 CRDT- 2016/10/12 06:00 PHST- 2016/04/27 00:00 [received] PHST- 2016/09/29 00:00 [accepted] PHST- 2016/10/12 06:00 [entrez] PHST- 2016/10/12 06:00 [pubmed] PHST- 2017/10/06 06:00 [medline] PHST- 2016/10/10 00:00 [pmc-release] AID - 10.1186/s12974-016-0739-8 [pii] AID - 739 [pii] AID - 10.1186/s12974-016-0739-8 [doi] PST - epublish SO - J Neuroinflammation. 2016 Oct 10;13(1):263. doi: 10.1186/s12974-016-0739-8.