PMID- 32452260 OWN - NLM STAT- MEDLINE DCOM- 20211230 LR - 20240226 IS - 1554-8635 (Electronic) IS - 1554-8627 (Print) IS - 1554-8627 (Linking) VI - 17 IP - 6 DP - 2021 Jun TI - Autophagy and post-ischemic conditioning in retinal ischemia. PG - 1479-1499 LID - 10.1080/15548627.2020.1767371 [doi] AB - Retinal ischemia is a major cause of vision loss and a common underlying mechanism associated with diseases, such as diabetic retinopathy and central retinal artery occlusion. We have previously demonstrated the robust neuroprotection in retina induced by post-conditioning (post-C), a brief period of ischemia, 24 h, following a prolonged and damaging initial ischemia. The mechanisms underlying post-C-mediated retinal protection are largely uncharacterized. We hypothesized that macroautophagy/autophagy is a mediator of post-C-induced neuroprotection. This study employed an in vitro model of oxygen glucose deprivation (OGD) in the retinal R28 neuronal cell line, and an in vivo rat model of retinal ischemic injury. In vivo, there were significant increases in autophagy proteins, MAP1LC3-II/LC3-II, and decreases in SQSTM1/p62 (sequestosome 1) in ischemia/post-C vs. ischemia/sham post-C. Blockade of Atg5 and Atg7 in vivo decreased LC3-II, increased SQSTM1, attenuated the functional protective effect of post-C, and increased histological damage and TUNEL compared to non-silencing siRNA. TUNEL after ischemia in vivo was found in retinal ganglion, amacrine, and photoreceptor cells. Blockade of Atg5 attenuated the post-C neuroprotection by a brief period of OGD in vitro. Moreover, in vitro, post-C attenuated cell death, loss of cellular proliferation, and defective autophagic flux from prolonged OGD. Stimulating autophagy using Tat-Beclin 1 rescued retinal neurons from cell death after OGD. As a whole, our results suggest that autophagy is required for the neuroprotective effect of retinal ischemic post-conditioning and augmentation of autophagy offers promise in the treatment of retinal ischemic injury.Abbreviations: BECN1: Beclin 1, autophagy related; DAPI: 4',6-diamidino-2-phenylindole; DR: diabetic retinopathy; EdU: 5-ethynyl-2'-deoxyuridine; ERG: Electroretinogram; FITC: Fluorescein isothiocyanate; GCL: Ganglion cell layer; GFAP: Glial fibrillary acidic protein; INL: Inner nuclear layer; IPL: Inner plexiform layer; MAP1LC3/LC3: Microtubule-associated protein 1 light chain 3; OGD: Oxygen-glucose deprivation; ONL: Outer nuclear layer; OP: Oscillatory potential; PFA: Paraformaldehyde; PL: Photoreceptor layer; post-C: post-conditioning; RFP: Red fluorescent protein; RGC: Retinal ganglion cell; RPE: Retinal pigment epithelium; RT-PCR: Real-time polymerase chain reaction; SEM: Standard error of the mean; siRNA: Small interfering RNA; SQSTM1: Sequestosome 1; STR: Scotopic threshold response; Tat: Trans-activator of transcription; TUNEL: Terminal deoxynucleotidyl transferase dUTP nick end labeling. FAU - Mathew, Biji AU - Mathew B AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. FAU - Chennakesavalu, Mohansrinivas AU - Chennakesavalu M AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. FAU - Sharma, Monica AU - Sharma M AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. FAU - Torres, Leianne A AU - Torres LA AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. FAU - Stelman, Clara R AU - Stelman CR AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. FAU - Tran, Sophie AU - Tran S AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. FAU - Patel, Raj AU - Patel R AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. FAU - Burg, Nathan AU - Burg N AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. FAU - Salkovski, Maryna AU - Salkovski M AD - Department of Chemistry, College of Liberal Arts and Sciences, University of Illinois at Chicago, Chicago, IL, USA. FAU - Kadzielawa, Konrad AU - Kadzielawa K AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. FAU - Seiler, Figen AU - Seiler F AD - Electron Microscopy Core Facility, University of Illinois at Chicago, Chicago, IL, USA. FAU - Aldrich, Leslie N AU - Aldrich LN AUID- ORCID: 0000-0001-8406-720X AD - Department of Chemistry, College of Liberal Arts and Sciences, University of Illinois at Chicago, Chicago, IL, USA. FAU - Roth, Steven AU - Roth S AUID- ORCID: 0000-0002-4955-9855 AD - Department of Anesthesiology, And College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. AD - Department of Ophthalmology and Visual Sciences, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA. LA - eng GR - P30 EY001792/EY/NEI NIH HHS/United States GR - R01 EY010343/EY/NEI NIH HHS/United States GR - R21 EY028690/EY/NEI NIH HHS/United States GR - UL1 TR002003/TR/NCATS NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural PT - Research Support, Non-U.S. Gov't DEP - 20200526 PL - United States TA - Autophagy JT - Autophagy JID - 101265188 RN - 0 (Beclin-1) RN - IY9XDZ35W2 (Glucose) RN - S88TT14065 (Oxygen) SB - IM MH - Animals MH - Astrocytes/metabolism MH - Autophagy/*physiology MH - Beclin-1/*metabolism MH - Cell Death/physiology MH - Glucose/*metabolism MH - *Ischemic Postconditioning/methods MH - Lysosomes/metabolism MH - Male MH - Oxygen/*metabolism MH - Rats, Wistar MH - Rats PMC - PMC8205079 OTO - NOTNLM OT - ATG proteins OT - LC3 OT - MTOR OT - SQSTM1/p62 OT - TUNEL OT - autophagic flux OT - macroautophagy/autophagy OT - post-ischemic conditioning OT - retina COIS- No potential conflict of interest was reported by the authors. EDAT- 2020/05/27 06:00 MHDA- 2021/12/31 06:00 PMCR- 2021/05/26 CRDT- 2020/05/27 06:00 PHST- 2020/05/27 06:00 [pubmed] PHST- 2021/12/31 06:00 [medline] PHST- 2020/05/27 06:00 [entrez] PHST- 2021/05/26 00:00 [pmc-release] AID - 1767371 [pii] AID - 10.1080/15548627.2020.1767371 [doi] PST - ppublish SO - Autophagy. 2021 Jun;17(6):1479-1499. doi: 10.1080/15548627.2020.1767371. Epub 2020 May 26.