PMID- 31683519 OWN - NLM STAT- MEDLINE DCOM- 20200330 LR - 20200728 IS - 1422-0067 (Electronic) IS - 1422-0067 (Linking) VI - 20 IP - 21 DP - 2019 Oct 31 TI - EPO and TMBIM3/GRINA Promote the Activation of the Adaptive Arm and Counteract the Terminal Arm of the Unfolded Protein Response after Murine Transient Cerebral Ischemia. LID - 10.3390/ijms20215421 [doi] LID - 5421 AB - Ischemic stroke is known to cause the accumulation of misfolded proteins and loss of calcium homeostasis leading to impairment of endoplasmic reticulum (ER) function. The unfolded protein response (UPR) is an ER-located and cytoprotective pathway that aims to resolve ER stress. Transmembrane BAX inhibitor-1 motif-containing (TMBIM) protein family member TMBIM3/GRINA is highly expressed in the brain and mostly located at the ER membrane suppressing ER calcium release by inositol-1,4,5-trisphosphate receptors. GRINA confers neuroprotection and is regulated by erythropoietin (EPO) after murine cerebral ischemia. However, the role of GRINA and the impact of EPO treatment on the post-ischemic UPR have not been elucidated yet. We subjected GRINA-deficient (Grina(-/-)) and wildtype mice to transient (30 min) middle cerebral artery occlusion (tMCAo) followed by 6 h or 72 h of reperfusion. We administered EPO or saline 0, 24 and 48 h after tMCAo/sham surgery. Oxygen-glucose deprivation (OGD) and pharmacological stimulation of the UPR using Tunicamycin and Thapsigargin were carried out in primary murine cortical mixed cell cultures. Treatment with the PERK-inhibitor GSK-2606414, IRE1a-RNase-inhibitor STF-083010 and EPO was performed 1 h prior to either 1 h, 2 h or 3 h of OGD. We found earlier and larger infarct demarcations in Grina(-/-) mice compared to wildtype mice, which was accompanied by a worse neurological outcome and an abolishment of EPO-mediated neuroprotection after ischemic stroke. In addition, GRINA-deficiency increased apoptosis and the activation of the corresponding PERK arm of the UPR after stroke. EPO enhanced the post-ischemic activation of pro-survival IRE1a and counteracted the pro-apoptotic PERK branch of the UPR. Both EPO and the PERK-inhibitor GSK-2606414 reduced cell death and regulated Grina mRNA levels after OGD. In conclusion, GRINA plays a crucial role in post-ischemic UPR and the use of both GSK-2606414 and EPO might lead to neuroprotection. FAU - Habib, Pardes AU - Habib P AUID- ORCID: 0000-0002-5771-216X AD - Department of Neurology, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany. phabib@ukaachen.de. FAU - Stamm, Ann-Sophie AU - Stamm AS AD - Department of Neurology, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany. ann-sophie.stamm@rwth-aachen.de. FAU - Schulz, Joerg B AU - Schulz JB AD - Department of Neurology, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany. jschulz@ukaachen.de. AD - JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging, Forschungszentrum Julich GmbAnd RWTH Aachen University, 52074 Aachen, Germany. jschulz@ukaachen.de. FAU - Reich, Arno AU - Reich A AD - Department of Neurology, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany. areich@ukaachen.de. FAU - Slowik, Alexander AU - Slowik A AD - Institute of Neuroanatomy, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany. aslowik@ukaachen.de. FAU - Capellmann, Sandro AU - Capellmann S AD - Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany. scapellmann@ukaachen.de. FAU - Huber, Michael AU - Huber M AD - Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany. mhuber@ukaachen.de. FAU - Wilhelm, Thomas AU - Wilhelm T AD - Institute of Biochemistry and Molecular Immunology, Medical Faculty, RWTH Aachen University, 52074 Aachen, Germany. twilhelm@ukaachen.de. LA - eng GR - START 111/17 PH/Medizinische Fakultat, RWTH Aachen University/ PT - Journal Article DEP - 20191031 PL - Switzerland TA - Int J Mol Sci JT - International journal of molecular sciences JID - 101092791 RN - 0 (7-methyl-5-(1-((3-(trifluoromethyl)phenyl)acetyl)-2,3-dihydro-1H-indol-5-yl)-7H-pyrrolo(2,3-d)pyrimidin-4-amine) RN - 0 (Grina protein, mouse) RN - 0 (Indoles) RN - 0 (Membrane Proteins) RN - 0 (Nerve Tissue Proteins) RN - 0 (Neuroprotective Agents) RN - 0 (STF 083010) RN - 0 (Sulfonamides) RN - 0 (Thiophenes) RN - 11089-65-9 (Tunicamycin) RN - 11096-26-7 (Erythropoietin) RN - 67526-95-8 (Thapsigargin) RN - IY9XDZ35W2 (Glucose) RN - JAC85A2161 (Adenine) RN - S88TT14065 (Oxygen) SB - IM MH - Adenine/analogs & derivatives/pharmacology MH - Animals MH - Apoptosis/drug effects/genetics MH - Cells, Cultured MH - Endoplasmic Reticulum Stress/drug effects/genetics MH - Erythropoietin/*pharmacology MH - Glucose/metabolism MH - Indoles/pharmacology MH - Infarction, Middle Cerebral Artery/genetics/metabolism/prevention & control MH - Ischemic Attack, Transient/genetics/metabolism/*prevention & control MH - Male MH - Membrane Proteins/genetics/*metabolism MH - Mice, 129 Strain MH - Mice, Inbred C57BL MH - Mice, Knockout MH - Nerve Tissue Proteins/genetics/*metabolism MH - Neuroprotective Agents/pharmacology MH - Oxygen/metabolism MH - Sulfonamides/pharmacology MH - Thapsigargin/pharmacology MH - Thiophenes/pharmacology MH - Tunicamycin/pharmacology MH - Unfolded Protein Response/*drug effects/genetics PMC - PMC6862264 OTO - NOTNLM OT - EPO OT - GRINA OT - GSK-2606414 OT - IRE1alpha OT - PERK OT - STF-083010 OT - UPR OT - neuroprotection OT - stroke COIS- The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. All experiments were conducted in compliance with the ARRIVE guidelines. The study was not pre-registered. The datasets of the current study are available from the corresponding author on reasonable request. EDAT- 2019/11/07 06:00 MHDA- 2020/03/31 06:00 PMCR- 2019/11/01 CRDT- 2019/11/06 06:00 PHST- 2019/09/25 00:00 [received] PHST- 2019/10/24 00:00 [revised] PHST- 2019/10/30 00:00 [accepted] PHST- 2019/11/06 06:00 [entrez] PHST- 2019/11/07 06:00 [pubmed] PHST- 2020/03/31 06:00 [medline] PHST- 2019/11/01 00:00 [pmc-release] AID - ijms20215421 [pii] AID - ijms-20-05421 [pii] AID - 10.3390/ijms20215421 [doi] PST - epublish SO - Int J Mol Sci. 2019 Oct 31;20(21):5421. doi: 10.3390/ijms20215421.