Extending Injury- and Disease-Tolerant Phenotypes by Repetitive Conditioning

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1 Extending Injury- and Disease-Tolerant Phenotypes by Repetitive Conditioning Promoting Long-Lasting Protection in the CNS Jeff Gidday PhD Neurosurgery Ophthalmology & Visual Sciences Cell Biology & Physiology Washington University School of Medicine Contact:

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4 CNS Disease Acute and Chronic Disease Stroke Retinal Ischemia and Glaucoma

5 Hypoxic Preconditioning newborn rat stroke Gidday et al., JCBFM, 1999

6 Infarct Volume (mm 3 ) Hypoxic preconditioning Adult mouse stroke Sham PC HPC Miller et al., NeuroReport, 2000 Wacker et al., JCBFM, 2012

7 CNS Disease Acute and Chronic Disease Stroke Retinal Ischemia Glaucoma

8 The Mammalian Retina anatomy refresher

9 Histology Hypoxic Preconditioning-Induced Protection Control Ischemia Hypoxic Preconditioning + Ischemia Zhu et al., IOVS, 2002

10 Flash Electroretinogram Quantifying the Retinal Response to Light 10-µsec flash

11 Hypoxic Preconditioning functional protection against retinal ischemia Zhu et al., IOVS, 2002

12 Ischemic Preconditioning Protection Against Retinal Ischemic Injury Roth et al., IOVS, 1998

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14 Transient Protection Rat Retina Roth et al., IOVS, 1998

15 Transient Protection Mouse Retina Percent of Nonischemic Controls Nonischemic controls Ischemia PC + ischemia 1 day later PC + ischemia 3 days later PC + ischemia 7 days later # # # # # # # 0 OLM-ILM INL IPL INL GCL layer thickness number of cells Zhu et al., IOVS, 2002

16 Retinal Phototoxicity Tolerance transient protection Experimental Protocol Liu C et al., J. Neurosci., 1998

17 Hypoxic preconditioning in adult transient focal stroke Reductions in leukocyte-endothelial adherence and infiltration 500 Leukocyte Adherence (number/mm 2 ) # # 0 N NT SHP 2 days SHP 2 wks N NT SHP 2 days SHP 2 wks Focal Ischemia TNF

18 Home Sweet Home?

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20 Magnitude Duration Frequency

21 Intermittent Hypoxia In vivo preclinical studies Promotes hippocampal neurogenesis (Zhu et al., J Neurosci 2010) Enhances proliferation of neuroprogenitor cells (Zhu et al., Brain Res 2005) Upregulates egr-1 and other survival-promoting transcription factors (Rybnikova et al., Behav Brain Res 2005) Protects against iron-, MPTP-, and kainic acidinduced neuronal injury (Lin et al., Exp Neurol 2002) Prevents mitochondrial DNA deletion and inhibits opening of MPTPs in heart (Zhu et al., J Mol Cell Cardiol 2006) Prolongs survival in a leukemic mouse model via tumor arrest and differentiation induction (Liu et al., Blood 2010)

22 Intermittent Hypoxia dose titration critical

23 Epaulette shark Hemiscyllium ocellatum

24 Repetitive Hypoxic Preconditioning RHP Experimental Design days ISCH weeks?? ISCH RHP = Systemic hypoxia (11% oxygen, 6 treatments over 2 wks)

25 Long-Term Tolerance Against Stroke Stowe et al., Ann Neurol. 2011

26 Control Long-Term Tolerance Against Retinal Ischemia Ischemia RHP + Ischemia (4 wks after RHP) Zhu et al., IOVS. 2007

27 Prolonged Retinal Ischemic Tolerance Following Repetitive Hypoxic Preconditioning (RHP) Thickness of OLN-ILM ( m) # # Thickness of IPL ( m) # # Thickness of INL ( m ) # # 0 Control Ischemia HP x 1 (1 wk) HP x 6 (4 wks) 0 Control Ischemia HP x 1 (1 wk) HP x 6 (4 wks) 0 Control Ischemia HP x 1 (1 wk) HP x 6 (4 wks) Single Hypoxic Preconditioning (HP x 1) Repetitive Hypoxic Preconditioning over 2 wks (HP x 6) Cell Density in INL (per 75 m) Control Ischemia # # HP x 1 (1 wk) HP x 6 (4 wks) Cell Density in GCL (per 250 m) Control Ischemia # # HP x 1 (1 wk) HP x 6 (4 wks) Zhu et al., IOVS, 2007

28 Prolonged Retinal Ischemic A Tolerance B Following Repetitive Hypoxic Preconditioning (RHP) Baseline Post-Ischemia Wave Amplitude (μv) C E D F Ischemia RHP + Ischemia (4 wks later) Stimulus Intensity (log cd.s/m 2 ) Zhu et al., IOVS, 2007

29 Intermittent Hypoxia for SCI sustained functional protection Lovett-Barr et al., J Neurosci., 2013

30 Mechanisms? H I F

31 Hypoxia-Inducible Factor-1 (HIF-1 ) and the Prolyl Hydroxylases Sharp & Bernaudin, Nat Rev Neurosci., 2004

32 Hypoxia-Induced HIF-1 Protein Expression Severity- and duration-dependent regulation 1 hour 6% O 2 Stroka et al., FASEB J, 2001

33 HIF-1 Drives Many Cell Survival Responses Sharp & Bernaudin, Nat Rev Neurosci., 2004

34 Retinal HIF-1 protein expression following hypoxic preconditioning (SHP vs. RHP) HIF-1 Protein (fold increase) # # # # RHP SHP RHP SHP Baseline C 0h C 0h 2h kda 120 kda 1 h after SHP 1 h after RHP 0-7 C Time after Preconditioning Stimulus (days) Zhu et al., IOVS, 2007

35 4 3 Retinal HO-1 protein expression following hypoxic preconditioning (SHP vs. RHP) # # # # RHP SHP Baseline 1 wk after SHP 4 wks after RHP HO-1 Protein (fold increase) 2 1 Ischemia SHP+Ischemia 1 wk later RHP+Ischemia 4 wks later 0-7 C Time after Preconditioning Stimulus (days) Zhu et al., IOVS, 2007

36 Cerebral HIF-1 dose-response single or repetitive hypoxia Shao G et al., Neurosignals, 2005

37 Daily Hypoxia......for Good Health????

38 Repetitive Pre-Conditioning for Neurodegenerative Disease? Injury / Disease weeks months

39 Repetitive Pre- and Post-Conditioning for Neurodegenerative Disease? Injury / Disease months years?

40 CNS Disease Acute and Chronic Disease Stroke Retinal Ischemia Glaucoma

41 Glaucoma Progressive retinal ganglion cell (RGC) death

42 Repetitive Preconditioning for Glaucoma Experimental Design Chronic Elevation of Intraocular Pressure 2 weeks Repetitive Hypoxic Preconditioning (RHP) Surgical induction of glaucoma 3 or 10 weeks RGC cell survival and function = Hypoxia (11% oxygen for 2 h)

43 Glaucoma Retinal ganglion cell injury/protection Morphology - Cell bodies (in retina) - Axons (in retina and optic nerve)

44 RGC Cell Body Survival Glaucoma eye Fellow eye Untreated RHP

45 RGC Axon Survival

46 RGC Axon Survival

47 RGC Axon Survival

48 Glaucoma Retinal ganglion cell injury/protection Morphology - Cell bodies (in retina) - Axons (in retina and optic nerve) Function - Visual acuity - Visual performance visual evoked potentials (VEPs)

49 Visual Acuity Optokinetic Response Prusky et al., IOVS, 2004

50 Flash Visual Evoked Potentials

51 Cell Body Survival 21% loss 2% loss 91% protection 30% loss 3% loss 87% protection Zhu et al., Mol Med, 2012

52 Axon Survival 5% loss 87% protection 35% loss Zhu et al., Mol Med, 2012

53 Repetitive Preconditioning GLAUCOMA months years

54 Repetitive Postconditioning GLAUCOMA months years

55 Intraocular Pressure Control 20.4 ± 0.6 mmhg 19.2 ± 0.6 mmhg RHP

56 Visual Performance 22-23% loss 6-9% loss 62-73% protection

57 Visual Acuity 30% loss 10% loss 67% protection

58 Retinal Ganglion Cells Cell Body Survival 16% loss 2% loss 85% protection

59 Retinal Ganglion Cells Axon Survival 19% loss 5% loss 74% protection

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63 Inheritance of Acquired Characteristics Jean-Baptiste Lamarck, 1809

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65 Transgenerational Epigenetics Experimental Design Gestation Growth/Maturation 4 months of Repetitive Hypoxic Preconditioning (RHP) + Normoxic Controls 3 wks 10 wks Retinal Ischemia Breeding Births ERGs

66 Transgenerational Epigenetics children inherit injury resilience of parents 21% loss 12% loss 61% protection 78% protection 54% loss 54% loss

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68 ACKNOWLEDGMENTS NIH (NEI, NINDS) The Glaucoma Foundation BrightFocus (AHAF) Spastic Paralysis Research Foundation of the Illinois-Eastern Iowa District of Kiwanis International