Bioenergetic Impairments and Increased Interferon-Stimulated Genes’ Expressions in Human Neurodegenerative Diseases

James P. Bennett, Jr1,2., Paula M. Keeney1,2 (pmaxkeeney@gmail.com), David G. Brohawn2,3(dbroh11@gmail.com), Amy C. Ladd2 (amy.ladd@vcuhealth.org), Knarik Arkun4 (knarik.arkun@tufts.edu), Ann C. Rice2 (acrice@reynolds.edu), Ravindar R. Thomas2 (thomas.rrs@gmail.com).

1Neurodegeneration Therapeutics, Inc.

Charlottesville, Virginia, USA

2Virginia Commonwealth University Parkinson’s and Movement Disorders Center

3Virginia Commonwealth University Department of Medical Genetics

4Virginia Commonwealth University, Department of Pathology (Neuropathology)

Richmond, Virginia, USA

Correspondence:

James P. Bennett, Jr. M.D., Ph.D.
Neurodegeneration Therapeutics, Inc.
3050A Berkmar Drive
Charlottesville, VA 22901-3450

jpb8u@icloud.com

www.NDTherapeutics.org

Abstract: Human neurodegenerative diseases (NDD’s) are commonly age-related, mostly genetically sporadic (non-monogenic) in occurrence, complex in etiology and clinical presentations, and demonstrate clinical phenotypes of Alzheimer’s dementia (AD), or Parkinson’s disease (PD) or motor neuron disease (a.k.a. amyotrophic lateral sclerosis, ALS), among others. NDD’s exact increasing personal and societal burdens as populations age and disease-altering specific therapies remain elusive. We presented data that, at least in postmortem samples from clinically advanced NDD subjects, mitochondrial bioenergetic impairments are reflected in reduced expression of genes required for ATP production and mitochondrial RNA stability. Mitochondrial proteins and nucleic acids can be damaged by oxidative/nitrative stresses during aging, and such damage appears increased in age-matched postmortem NDD samples. Such “mitochondrial stress” may lead to increased release of mitochondrial DNA (mtDNA) into cytosol, activating the innate immune system through the cGAS-STING system. We discuss this possibility and present evidence that expressions of several interferon-stimulated genes (ISG’s) are increased in NDD brain samples. If present, cGAS-STING activation from mtDNA leakage could contribute to neuroinflammation seen in NDD brains and presents an additional potential therapeutic target.

Keywords: human neurodegenerative brain diseases, mitochondrial DNA, mitochondrial oxidative phosphorylation, oxidative stress, neuro-inflammation, interferon-stimulated gene expression, cGAS-STING

Introduction

Neurodegenerative diseases (NDD’s) are characterized by clinical phenotypes that derive from neuronal dysfunction and degeneration. NDDs’ incidences generally increase with aging, occur sporadically except for rare monogenic variants that frequently are familial, exact increasing personal and societal tolls and are commonly causal for death of afflicted individuals. For the most common adult NDD’s, current estimates are that on a world-wide basis, about 30-35 million persons suffer from dementia caused by Alzheimer’s disease (AD), over 10 million suffer from Parkinson’s disease (PD), and about 450,000 are living with amyotrophic lateral sclerosis (ALS, a.k.a. motor neuron disease).

NDD’s are complex medical problems with likely multi-factorial etiologies. As a group, they are among the most debilitating of chronic illnesses of adults, have defied discovery of disease-altering therapies and appear to represent interactions between general brain aging processes and disease-specific molecular pathologies.

Because NDD’s likely appear pathologically over years/decades, chronic mechanisms compared to acute conditions (such as infections, strokes, drug toxicities, etc) are likely etiologic. Two contenders, among several possibilities, that have emerged over the last decade are progressive bioenergetic impairment due to mitochondrial damage and neuroinflammation mediated by the cGAS-STING double-stranded nucleic acid detection system.[1-13]

Mitochondrial bioenergetic deficits have been reported in human brain and animal/cellular models of NDD’s, including amyotrophic lateral sclerosis (ALS) [14-19], Alzheimer’s disease (AD) [14 18 20-29] and Parkinson’s disease (PD) [14 18 23 25 30-49]. These deficits in ATP production may arise from oxidative stress damage [15-17 19 50-53] (ALS); [20-23 26 28 29 51 52 54-65] (AD); and [23 33 34 36 38 39 41 43-45 47 48 51 52 66-72] (PD).

We presented gene expression data from our studies of postmortem NDD brain (AD, PD) and cervical spinal cord (ALS) tissues that support bioenergetic deficiencies in ATP production mediated by OXPHOS) [73-79] and activation of the cGAS-STING system (present study). We also reviewed biochemical and physiological studies from our group and others (see above) that have in toto allowed construction of the hypothesis that NDD’s arise over time from a combination of “wear and tear” on the brain mitochondrial bioenergetic machinery, which could lead to release of mitochondrial DNA (mtDNA) into neuronal cytosol [5 12 52], resulting in activation of the cGAS-STING innate immunity system mediated by increased expression of interferon-stimulated genes (ISG’s) [1-3 6 8-13]. Activation of the cGAS-STING system has been recently demonstrated in human motor neuron IPSC’s and ALS spinal cord homogenates [12]. These ISG’s following cGAS-STING stimulation of expression can cause apoptosis of neurons through multiple mechanisms and can be blocked by recently described cGAS inhibitor small molecules. If this hypothesis is correct, then combined neuroprotective therapy could include mitochondrially concentrated, antioxidative drug(s) and cGAS inhibitor(s) [1-8 80 81].

Results

Postmortem NDD tissues have reduced copy numbers of mitochondrial DNA (mtDNA)

Using quantitative PCR for several mtDNA genes, we showed reduced mtDNA copy numbers in laser-captured neurons of ALS cervical spinal cord [77] in the setting of heterogenous distributions of mtDNA’s in anterior motor neurons. We compared the distribution of mtDNA genes and also found an increase in ALS of deleted mtDNA species [77]. In laser-captured isolated AD hippocampal pyramidal neurons [82] we compared distributions of mtDNA copy numbers and found an altered distribution of mtDNA gene levels. In PD samples, nigral neurons with Lewy bodies (LB+) had on average ~4-fold increased copy numbers of mtDNA compared to LB(-) neurons [83].

Postmortem NDD tissues show reduced expression of OXPHOS genes

By RT-qPCR (ALS, [79]) or RNAseq (ALS [78], AD [74] or PD [74]) expressions of mtDNA OXPHOS genes appear reduced in cervical spinal cord sections (ALS) or LCM-isolated motorneurons (ALS), frontal cortical ribbon (AD) or ventral midbrain (PD). These findings suggested that in all three adult NDD’s, synthesis of ATP is impaired.

Postmortem NDD (AD or PD) tissues show reduced expression of mtRNA stabilizing protein

Using RNAseq, we showed that AD (frontal cortical ribbon) and PD (ventral midbrain) postmortem brain tissues showed reduced expression of LRPPRC ([74], a.k.a. LRP130), a mtRNA stabilizing protein [74 84 85]. This finding suggested that at least part of the reduced expression of mtDNA OXPHOS genes we observed in AD and PD brains could derive from reduced mtRNA stability.

Elevated expression of selected Interferon-Stimulated Genes (ISG) is increased in postmortem AD and ALS tissues.

We used RNAseq analysis of postmortem AD, PD and ALS tissues to assess expression levels of 47 type I interferon-stimulated genes based on their involvement in apoptosis, immune modulation, cell attraction and adhesion, or antiviral and pathogen detection [8]. The results are shown in Fig 1. From that list, we selected 12 genes (CASP4, BAK1, PLSCR1, XAF1, IRF5, IRF7, IL12, VEGFC, EGF1, OAS1, ISG15, ISG20) that exhibited the following expression patterns:

  1. Gene expression was found in tissues from all 3 diseases (ALS, AD, PD), and at least 2/3 genes showed expression > 100% of control
  2. Gene expression was found in 2 out of 3 diseases, and expression of least 1 out of 2 genes was > 200% of control.

We then performed 2-way ANOVA’s on these gene sets. We observed that the patterns of ISG expression elevation were significant for AD frontal cortical ribbon (n=9 CTL, 8 AD) (F=1, 191; p=0.0103) and ALS cervical spinal cord (n=6 CTL, 7 ALS) (F=1,143; p=0.0017) but not for PD ventral midbrain (n=7 CTL, 13 PD) (F=1, 227; p=0.3367). These results on small postmortem tissue sets indicate that expressions of type I interferon-stimulated genes [8] can be increased in some NDD’s, and that the cGAS-STING pathway may be overly activated in these diseases.

Discussion

Release of double-stranded (ds) mtDNA into cell cytosol is viewed as a potent stimulant for activation of cGAS-STING innate immunity signaling, with increased transcription of multiple interferon-stimulated genes [1 2 4-8 10-13 81 86]. Such activation may play a role in neurodegeneration [2 8 10 12 86]. Mitochondrial bioenergetic deficits that can arise from oxidative stress damage to either OXPHOS proteins or mtDNA itself [52 77 86] may trigger neuronal apoptosis, which itself can be a potent activator of the cGAS-STING pathway [86].

In the present study, we have reviewed past studies that showed post-mortem brain (AD, PD) or cervical spinal cord (ALS) tissues and isolated neurons (ALS, [78]) from subjects who died with advanced clinical phenotypes showed evidence of both bioenergetic deficits (decreased expression of OXPHOS genes [74 79 87]) and possible mtRNA instability (decreased expression of mtRNA stabilizing protein [74]). We now show potential activation of the cGAS-STING pathway (increased ISG expression, present study).

Our studies are limited by small numbers of each disease type. Whether such changes are found in larger disease populations await examinations of those larger, heterogenous populations. Also, our findings shed no insight into the problem of selective vulnerability of neuronal populations in each pathological phenotype.

However, in spite of these important limitations, our findings suggest a unifying mechanism of neurodegeneration, composed of mitochondrial bioenergetic deficit, leading to apoptosis of neuronal populations, which results in a clinical phenotype that is worsened by neuroinflammation (cGAS-STING activation). If this formulation is relevant, then combination treatment with antioxidative stress agents, mitochondrial biogenesis activators and cGAS inhibitors could be therapeutic for multiple NDD’s.

This formulation of NDD etiology does not require designation of a particular “genesis event (or events)” that initiate(s) the neurodegenerative cascade. Instead, it is more pragmatic, in that it addresses pathophysiological processes that arise for whatever reason, and the “reasons” may vary from person-person.

Methods

All of the data presented in this paper has been previously published, as have the methods and subject demographics [73 74 76-79]. The data for construction of Figure 1 were derived from these prior studies and used GraphPad Prism v. 9.0.2 for statistical analyses.

Author Contributions: JPB participated in design of all experiments and wrote the manuscript draft. PMK supervised all AD and PD tissues and their RNA/DNA extractions. ACL and DGB participated in experiments involving analyses of ALS tissues. ACR and RRT participated in experiments involving laser capture and analyses of AD tissues. KA and ACR participated in experiments involving laser capture of PD substantia nigra Lewy body (+) and Lewy body (-) neurons. All authors have seen and agree with the final manuscript version.

Ethics Statement: No animals were used in these experiments. Human tissues were obtained either from a non-profit source that had their own IRB oversight (National Disease Research Interchange, Philadelphia, PA http://www.ndriresource.org; ALS/CTL cervical spinal cord), or under local IRB supervision (most AD/CTL and most PD/CTL), or were considered “autopsy tissue” and did not require IRB oversight (some AD/CTL and some PD/CTL). JPB is the inventor on US and EU patents regarding the use of R(+) pramipexole in NDD’s. The authors otherwise declare no competing interests.

Data Availability: RNAseq files that have had Illumina sequencing adapters removed (by Trimmomatic) are available free of charge to all academic and non-profit institutional investigators following queries directed to the corresponding author (JPB).

Figure 1

Figure Legends

Figure 1. Figure 1 shows interferon-stimulated gene (ISG) [8] expression levels measured by RNAseq in postmortem tissue homogenates from Alzheimer disease (AD, red bars, frontal cortical ribbon), or Parkinson disease (PD, green bars, ventral midbrain), or amyotrophic lateral sclerosis (ALS, blue bars, cervical spinal cord), presented as mean % control values. 2-way ANOVA for each NDD (versus CTL) revealed p= 0.0103 (AD), p=0.3367 (PD) or p=0.0017 (ALS). See text for details.

References Cited

1. Cheng Z, Dai T, He X, et al. The interactions between cGAS-STING pathway and pathogens. Signal Transduct Target Ther 2020;5(1):91 doi: 10.1038/s41392-020-0198-7[published Online First: Epub Date]|.

2. Chin AC. Neuroinflammation and the cGAS-STING pathway. J Neurophysiol 2019;121(4):1087-91 doi: 10.1152/jn.00848.2018[published Online First: Epub Date]|.

3. Fu Y, Fang Y, Lin Z, et al. Inhibition of cGAS-Mediated Interferon Response Facilitates Transgene Expression. iScience 2020;23(4):101026 doi: 10.1016/j.isci.2020.101026[published Online First: Epub Date]|.

4. Gao M, He Y, Tang H, Chen X, Liu S, Tao Y. cGAS/STING: novel perspectives of the classic pathway. Molecular Biomedicine 2020;1(1) doi: 10.1186/s43556-020-00006-z[published Online First: Epub Date]|.

5. Hu M, Zhou M, Bao X, et al. ATM inhibition enhances cancer immunotherapy by promoting mtDNA leakage and cGAS/STING activation. J Clin Invest 2021;131(3) doi: 10.1172/JCI139333[published Online First: Epub Date]|.

6. Jiang M, Chen P, Wang L, et al. cGAS-STING, an important pathway in cancer immunotherapy. J Hematol Oncol 2020;13(1):81 doi: 10.1186/s13045-020-00916-z[published Online First: Epub Date]|.

7. Kwon J, Bakhoum SF. The Cytosolic DNA-Sensing cGAS-STING Pathway in Cancer. Cancer Discov 2020;10(1):26-39 doi: 10.1158/2159-8290.CD-19-0761[published Online First: Epub Date]|.

8. Li Y, Wilson HL, Kiss-Toth E. Regulating STING in health and disease. J Inflamm (Lond) 2017;14:11 doi: 10.1186/s12950-017-0159-2[published Online First: Epub Date]|.

9. Parekh NJ, Krouse TE, Reider IE, Hobbs RP, Ward BM, Norbury CC. Type I interferon-dependent CCL4 is induced by a cGAS/STING pathway that bypasses viral inhibition and protects infected tissue, independent of viral burden. PLoS Pathog 2019;15(10):e1007778 doi: 10.1371/journal.ppat.1007778[published Online First: Epub Date]|.

10. Wan D, Jiang W, Hao J. Research Advances in How the cGAS-STING Pathway Controls the Cellular Inflammatory Response. Front Immunol 2020;11:615 doi: 10.3389/fimmu.2020.00615[published Online First: Epub Date]|.

11. Wang Y, Luo J, Alu A, Han X, Wei Y, Wei X. cGAS-STING pathway in cancer biotherapy. Mol Cancer 2020;19(1):136 doi: 10.1186/s12943-020-01247-w[published Online First: Epub Date]|.

12. Yu CH, Davidson S, Harapas CR, et al. TDP-43 Triggers Mitochondrial DNA Release via mPTP to Activate cGAS/STING in ALS. Cell 2020;183(3):636-49 e18 doi: 10.1016/j.cell.2020.09.020[published Online First: Epub Date]|.

13. Zheng J, Mo J, Zhu T, et al. Comprehensive elaboration of the cGAS-STING signaling axis in cancer development and immunotherapy. Mol Cancer 2020;19(1):133 doi: 10.1186/s12943-020-01250-1[published Online First: Epub Date]|.

14. Adhihetty PJ, Beal MF. Creatine and its potential therapeutic value for targeting cellular energy impairment in neurodegenerative diseases. Neuromolecular Med 2008;10(4):275-90 doi: 10.1007/s12017-008-8053-y[published Online First: Epub Date]|.

15. Andreassen OA, Jenkins BG, Dedeoglu A, et al. Increases in cortical glutamate concentrations in transgenic amyotrophic lateral sclerosis mice are attenuated by creatine supplementation. J Neurochem 2001;77(2):383-90 doi: 10.1046/j.1471-4159.2001.00188.x[published Online First: Epub Date]|.

16. Coussee E, De Smet P, Bogaert E, et al. G37R SOD1 mutant alters mitochondrial complex I activity, Ca(2+) uptake and ATP production. Cell Calcium 2011;49(4):217-25 doi: 10.1016/j.ceca.2011.02.004[published Online First: Epub Date]|.

17. Ghiasi P, Hosseinkhani S, Noori A, Nafissi S, Khajeh K. Mitochondrial complex I deficiency and ATP/ADP ratio in lymphocytes of amyotrophic lateral sclerosis patients. Neurol Res 2012;34(3):297-303 doi: 10.1179/1743132812Y.0000000012[published Online First: Epub Date]|.

18. Panchal K, Tiwari AK. Mitochondrial dynamics, a key executioner in neurodegenerative diseases. Mitochondrion 2019;47:151-73 doi: 10.1016/j.mito.2018.11.002[published Online First: Epub Date]|.

19. Parone PA, Da Cruz S, Han JS, et al. Enhancing mitochondrial calcium buffering capacity reduces aggregation of misfolded SOD1 and motor neuron cell death without extending survival in mouse models of inherited amyotrophic lateral sclerosis. J Neurosci 2013;33(11):4657-71 doi: 10.1523/JNEUROSCI.1119-12.2013[published Online First: Epub Date]|.

20. Chen Z, Zhong C. Decoding Alzheimer’s disease from perturbed cerebral glucose metabolism: implications for diagnostic and therapeutic strategies. Prog Neurobiol 2013;108:21-43 doi: 10.1016/j.pneurobio.2013.06.004[published Online First: Epub Date]|.

21. Daulatzai MA. Cerebral hypoperfusion and glucose hypometabolism: Key pathophysiological modulators promote neurodegeneration, cognitive impairment, and Alzheimer’s disease. J Neurosci Res 2017;95(4):943-72 doi: 10.1002/jnr.23777[published Online First: Epub Date]|.

22. Dixit S, Fessel JP, Harrison FE. Mitochondrial dysfunction in the APP/PSEN1 mouse model of Alzheimer’s disease and a novel protective role for ascorbate. Free Radic Biol Med 2017;112:515-23 doi: 10.1016/j.freeradbiomed.2017.08.021[published Online First: Epub Date]|.

23. Janssen CI, Kiliaan AJ. Long-chain polyunsaturated fatty acids (LCPUFA) from genesis to senescence: the influence of LCPUFA on neural development, aging, and neurodegeneration. Prog Lipid Res 2014;53:1-17 doi: 10.1016/j.plipres.2013.10.002[published Online First: Epub Date]|.

24. Kulic L, Wollmer MA, Rhein V, et al. Combined expression of tau and the Harlequin mouse mutation leads to increased mitochondrial dysfunction, tau pathology and neurodegeneration. Neurobiol Aging 2011;32(10):1827-38 doi: 10.1016/j.neurobiolaging.2009.10.014[published Online First: Epub Date]|.

25. Lamarre NS, Braverman AS, Malykhina AP, Barbe MF, Ruggieri MR, Sr. Alterations in nerve-evoked bladder contractions in a coronavirus-induced mouse model of multiple sclerosis. PLoS One 2014;9(10):e109314 doi: 10.1371/journal.pone.0109314[published Online First: Epub Date]|.

26. Nguyen HT, Chen M. High-energy compounds mobilize intracellular Ca2+ and activate calpain in cultured cells: is calpain an energy-dependent protease? Brain Res Bull 2014;102:9-14 doi: 10.1016/j.brainresbull.2014.01.006[published Online First: Epub Date]|.

27. Rhein V, Giese M, Baysang G, et al. Ginkgo biloba extract ameliorates oxidative phosphorylation performance and rescues abeta-induced failure. PLoS One 2010;5(8):e12359 doi: 10.1371/journal.pone.0012359[published Online First: Epub Date]|.

28. Thomas SC, Alhasawi A, Appanna VP, Auger C, Appanna VD. Brain metabolism and Alzheimer’s disease: the prospect of a metabolite-based therapy. J Nutr Health Aging 2015;19(1):58-63 doi: 10.1007/s12603-014-0511-7[published Online First: Epub Date]|.

29. Yin J, Nielsen M, Li S, Shi J. Ketones improves Apolipoprotein E4-related memory deficiency via sirtuin 3. Aging (Albany NY) 2019;11(13):4579-86 doi: 10.18632/aging.102070[published Online First: Epub Date]|.

30. Dabbeni-Sala F, Di Santo S, Franceschini D, Skaper SD, Giusti P. Melatonin protects against 6-OHDA-induced neurotoxicity in rats: a role for mitochondrial complex I activity. FASEB J 2001;15(1):164-70 doi: 10.1096/fj.00-0129com[published Online First: Epub Date]|.

31. Dalton CM, Szabadkai G, Carroll J. Measurement of ATP in single oocytes: impact of maturation and cumulus cells on levels and consumption. J Cell Physiol 2014;229(3):353-61 doi: 10.1002/jcp.24457[published Online First: Epub Date]|.

32. Dos-Santos-Pereira M, Acuna L, Hamadat S, et al. Microglial glutamate release evoked by alpha-synuclein aggregates is prevented by dopamine. Glia 2018;66(11):2353-65 doi: 10.1002/glia.23472[published Online First: Epub Date]|.

33. Dragicevic E, Schiemann J, Liss B. Dopamine midbrain neurons in health and Parkinson’s disease: emerging roles of voltage-gated calcium channels and ATP-sensitive potassium channels. Neuroscience 2015;284:798-814 doi: 10.1016/j.neuroscience.2014.10.037[published Online First: Epub Date]|.

34. Haglin L. High serum phosphate concentration as the result of smoking might underlie the lower risk of Parkinson’s disease. Med Hypotheses 2015;85(3):287-90 doi: 10.1016/j.mehy.2015.05.017[published Online First: Epub Date]|.

35. Hilker R, Pilatus U, Eggers C, et al. The bioenergetic status relates to dopamine neuron loss in familial PD with PINK1 mutations. PLoS One 2012;7(12):e51308 doi: 10.1371/journal.pone.0051308[published Online First: Epub Date]|.

36. Iannielli A, Bido S, Folladori L, et al. Pharmacological Inhibition of Necroptosis Protects from Dopaminergic Neuronal Cell Death in Parkinson’s Disease Models. Cell Rep 2018;22(8):2066-79 doi: 10.1016/j.celrep.2018.01.089[published Online First: Epub Date]|.

37. Klivenyi P, Kekesi KA, Hartai Z, Juhasz G, Vecsei L. Effects of mitochondrial toxins on the brain amino acid concentrations. Neurochem Res 2005;30(11):1421-7 doi: 10.1007/s11064-005-8512-x[published Online First: Epub Date]|.

38. Liu HF, Ho PW, Leung GC, et al. Combined LRRK2 mutation, aging and chronic low dose oral rotenone as a model of Parkinson’s disease. Sci Rep 2017;7:40887 doi: 10.1038/srep40887[published Online First: Epub Date]|.

39. Liu W, Vives-Bauza C, Acin-Perez R, et al. PINK1 defect causes mitochondrial dysfunction, proteasomal deficit and alpha-synuclein aggregation in cell culture models of Parkinson’s disease. PLoS One 2009;4(2):e4597 doi: 10.1371/journal.pone.0004597[published Online First: Epub Date]|.

40. Magnoni R, Palmfeldt J, Christensen JH, et al. Late onset motoneuron disorder caused by mitochondrial Hsp60 chaperone deficiency in mice. Neurobiol Dis 2013;54:12-23 doi: 10.1016/j.nbd.2013.02.012[published Online First: Epub Date]|.

41. Morais VA, Verstreken P, Roethig A, et al. Parkinson’s disease mutations in PINK1 result in decreased Complex I activity and deficient synaptic function. EMBO Mol Med 2009;1(2):99-111 doi: 10.1002/emmm.200900006[published Online First: Epub Date]|.

42. Muddapu VR, Chakravarthy VS. Influence of energy deficiency on the subcellular processes of Substantia Nigra Pars Compacta cell for understanding Parkinsonian neurodegeneration. Sci Rep 2021;11(1):1754 doi: 10.1038/s41598-021-81185-9[published Online First: Epub Date]|.

43. Norwitz NG, Hu MT, Clarke K. The Mechanisms by Which the Ketone Body D-beta-Hydroxybutyrate May Improve the Multiple Cellular Pathologies of Parkinson’s Disease. Front Nutr 2019;6:63 doi: 10.3389/fnut.2019.00063[published Online First: Epub Date]|.

44. Patki G, Che Y, Lau YS. Mitochondrial dysfunction in the striatum of aged chronic mouse model of Parkinson’s disease. Front Aging Neurosci 2009;1:3 doi: 10.3389/neuro.24.003.2009[published Online First: Epub Date]|.

45. Pinheiro-Carrera M, Tomaz C, Huston JP, Dai H, Carey RJ. L-dopa induced increases in brain uric acid in an animal model of Parkinson’s disease: a relationship to behavioral activation. Life Sci 1994;55(13):991-7 doi: 10.1016/0024-3205(94)00633-4[published Online First: Epub Date]|.

46. Przedborski S, Jackson-Lewis V, Djaldetti R, et al. The parkinsonian toxin MPTP: action and mechanism. Restor Neurol Neurosci 2000;16(2):135-42

47. Rabaneda-Lombarte N, Xicoy-Espaulella E, Serratosa J, Saura J, Sola C. Parkinsonian Neurotoxins Impair the Pro-inflammatory Response of Glial Cells. Front Mol Neurosci 2018;11:479 doi: 10.3389/fnmol.2018.00479[published Online First: Epub Date]|.

48. Tretter L, Sipos I, Adam-Vizi V. Initiation of neuronal damage by complex I deficiency and oxidative stress in Parkinson’s disease. Neurochem Res 2004;29(3):569-77 doi: 10.1023/b:nere.0000014827.94562.4b[published Online First: Epub Date]|.

49. Vincent A, Briggs L, Chatwin GF, et al. parkin-induced defects in neurophysiology and locomotion are generated by metabolic dysfunction and not oxidative stress. Hum Mol Genet 2012;21(8):1760-9 doi: 10.1093/hmg/ddr609[published Online First: Epub Date]|.

50. Bozzo F, Mirra A, Carri MT. Oxidative stress and mitochondrial damage in the pathogenesis of ALS: New perspectives. Neurosci Lett 2017;636:3-8 doi: 10.1016/j.neulet.2016.04.065[published Online First: Epub Date]|.

51. Butterfield DA, Castegna A, Drake J, Scapagnini G, Calabrese V. Vitamin E and neurodegenerative disorders associated with oxidative stress. Nutr Neurosci 2002;5(4):229-39 doi: 10.1080/10284150290028954[published Online First: Epub Date]|.

52. Islam MT. Oxidative stress and mitochondrial dysfunction-linked neurodegenerative disorders. Neurol Res 2017;39(1):73-82 doi: 10.1080/01616412.2016.1251711[published Online First: Epub Date]|.

53. Wang Z, Bai Z, Qin X, Cheng Y. Aberrations in Oxidative Stress Markers in Amyotrophic Lateral Sclerosis: A Systematic Review and Meta-Analysis. Oxid Med Cell Longev 2019;2019:1712323 doi: 10.1155/2019/1712323[published Online First: Epub Date]|.

54. Butterfield DA. Amyloid beta-peptide (1-42)-induced oxidative stress and neurotoxicity: implications for neurodegeneration in Alzheimer’s disease brain. A review. Free Radic Res 2002;36(12):1307-13 doi: 10.1080/1071576021000049890[published Online First: Epub Date]|.

55. Butterfield DA, Griffin S, Munch G, Pasinetti GM. Amyloid beta-peptide and amyloid pathology are central to the oxidative stress and inflammatory cascades under which Alzheimer’s disease brain exists. J Alzheimers Dis 2002;4(3):193-201 doi: 10.3233/jad-2002-4309[published Online First: Epub Date]|.

56. Butterfield DA, Kanski J. Methionine residue 35 is critical for the oxidative stress and neurotoxic properties of Alzheimer’s amyloid beta-peptide 1-42. Peptides 2002;23(7):1299-309 doi: 10.1016/s0196-9781(02)00066-9[published Online First: Epub Date]|.

57. Butterfield DA, Lauderback CM. Lipid peroxidation and protein oxidation in Alzheimer’s disease brain: potential causes and consequences involving amyloid beta-peptide-associated free radical oxidative stress. Free Radic Biol Med 2002;32(11):1050-60 doi: 10.1016/s0891-5849(02)00794-3[published Online First: Epub Date]|.

58. Chang YT, Chang WN, Tsai NW, et al. The roles of biomarkers of oxidative stress and antioxidant in Alzheimer’s disease: a systematic review. Biomed Res Int 2014;2014:182303 doi: 10.1155/2014/182303[published Online First: Epub Date]|.

59. Cheignon C, Tomas M, Bonnefont-Rousselot D, Faller P, Hureau C, Collin F. Oxidative stress and the amyloid beta peptide in Alzheimer’s disease. Redox Biol 2018;14:450-64 doi: 10.1016/j.redox.2017.10.014[published Online First: Epub Date]|.

60. Chen Z, Zhong C. Oxidative stress in Alzheimer’s disease. Neurosci Bull 2014;30(2):271-81 doi: 10.1007/s12264-013-1423-y[published Online First: Epub Date]|.

61. Kanski J, Aksenova M, Schoneich C, Butterfield DA. Substitution of isoleucine-31 by helical-breaking proline abolishes oxidative stress and neurotoxic properties of Alzheimer’s amyloid beta-peptide. Free Radic Biol Med 2002;32(11):1205-11 doi: 10.1016/s0891-5849(02)00821-3[published Online First: Epub Date]|.

62. Kanski J, Varadarajan S, Aksenova M, Butterfield DA. Role of glycine-33 and methionine-35 in Alzheimer’s amyloid beta-peptide 1-42-associated oxidative stress and neurotoxicity. Biochim Biophys Acta 2002;1586(2):190-8 doi: 10.1016/s0925-4439(01)00097-7[published Online First: Epub Date]|.

63. LaFontaine MA, Mattson MP, Butterfield DA. Oxidative stress in synaptosomal proteins from mutant presenilin-1 knock-in mice: implications for familial Alzheimer’s disease. Neurochem Res 2002;27(5):417-21 doi: 10.1023/a:1015560116208[published Online First: Epub Date]|.

64. Tonnies E, Trushina E. Oxidative Stress, Synaptic Dysfunction, and Alzheimer’s Disease. J Alzheimers Dis 2017;57(4):1105-21 doi: 10.3233/JAD-161088[published Online First: Epub Date]|.

65. Wang X, Wang W, Li L, Perry G, Lee HG, Zhu X. Oxidative stress and mitochondrial dysfunction in Alzheimer’s disease. Biochim Biophys Acta 2014;1842(8):1240-7 doi: 10.1016/j.bbadis.2013.10.015[published Online First: Epub Date]|.

66. Guo JD, Zhao X, Li Y, Li GR, Liu XL. Damage to dopaminergic neurons by oxidative stress in Parkinson’s disease (Review). Int J Mol Med 2018;41(4):1817-25 doi: 10.3892/ijmm.2018.3406[published Online First: Epub Date]|.

67. Khan Z, Ali SA. Oxidative stress-related biomarkers in Parkinson’s disease: A systematic review and meta-analysis. Iran J Neurol 2018;17(3):137-44

68. Nguyen M, Wong YC, Ysselstein D, Severino A, Krainc D. Synaptic, Mitochondrial, and Lysosomal Dysfunction in Parkinson’s Disease. Trends Neurosci 2019;42(2):140-49 doi: 10.1016/j.tins.2018.11.001[published Online First: Epub Date]|.

69. Poewe W, Seppi K, Tanner CM, et al. Parkinson disease. Nat Rev Dis Primers 2017;3:17013 doi: 10.1038/nrdp.2017.13[published Online First: Epub Date]|.

70. Raza C, Anjum R, Shakeel NUA. Parkinson’s disease: Mechanisms, translational models and management strategies. Life Sci 2019;226:77-90 doi: 10.1016/j.lfs.2019.03.057[published Online First: Epub Date]|.

71. Trist BG, Hare DJ, Double KL. Oxidative stress in the aging substantia nigra and the etiology of Parkinson’s disease. Aging Cell 2019;18(6):e13031 doi: 10.1111/acel.13031[published Online First: Epub Date]|.

72. Wei Z, Li X, Li X, Liu Q, Cheng Y. Oxidative Stress in Parkinson’s Disease: A Systematic Review and Meta-Analysis. Front Mol Neurosci 2018;11:236 doi: 10.3389/fnmol.2018.00236[published Online First: Epub Date]|.

73. Bennett JP, Keeney PM. RNA-Sequencing Reveals Similarities and Differences in Gene Expression in Vulnerable Brain Tissues of Alzheimer’s and Parkinson’s Diseases. J Alzheimers Dis Rep 2018;2(1):129-37 doi: 10.3233/ADR-180072[published Online First: Epub Date]|.

74. Bennett JP, Jr., Keeney PM. Alzheimer’s and Parkinson’s brain tissues have reduced expression of genes for mtDNA OXPHOS Proteins, mitobiogenesis regulator PGC-1alpha protein and mtRNA stabilizing protein LRPPRC (LRP130). Mitochondrion 2020;53:154-57 doi: 10.1016/j.mito.2020.05.012[published Online First: Epub Date]|.

75. Bennett JP, Jr., Keeney PM, Brohawn DG. RNA Sequencing Reveals Small and Variable Contributions of Infectious Agents to Transcriptomes of Postmortem Nervous Tissues From Amyotrophic Lateral Sclerosis, Alzheimer’s Disease and Parkinson’s Disease Subjects, and Increased Expression of Genes From Disease-Activated Microglia. Front Neurosci 2019;13:235 doi: 10.3389/fnins.2019.00235[published Online First: Epub Date]|.

76. Brohawn DG, O’Brien LC, Bennett JP, Jr. RNAseq Analyses Identify Tumor Necrosis Factor-Mediated Inflammation as a Major Abnormality in ALS Spinal Cord. PLoS One 2016;11(8):e0160520 doi: 10.1371/journal.pone.0160520[published Online First: Epub Date]|.

77. Keeney PM, Bennett JP, Jr. ALS spinal neurons show varied and reduced mtDNA gene copy numbers and increased mtDNA gene deletions. Mol Neurodegener 2010;5:21 doi: 10.1186/1750-1326-5-21[published Online First: Epub Date]|.

78. Ladd AC, Brohawn DG, Thomas RR, et al. RNA-seq analyses reveal that cervical spinal cords and anterior motor neurons from amyotrophic lateral sclerosis subjects show reduced expression of mitochondrial DNA-encoded respiratory genes, and rhTFAM may correct this respiratory deficiency. Brain Res 2017;1667:74-83 doi: 10.1016/j.brainres.2017.05.010[published Online First: Epub Date]|.

79. Ladd AC, Keeney PM, Govind MM, Bennett JP, Jr. Mitochondrial oxidative phosphorylation transcriptome alterations in human amyotrophic lateral sclerosis spinal cord and blood. Neuromolecular Med 2014;16(4):714-26 doi: 10.1007/s12017-014-8321-y[published Online First: Epub Date]|.

80. Hall J, Brault A, Vincent F, et al. Discovery of PF-06928215 as a high affinity inhibitor of cGAS enabled by a novel fluorescence polarization assay. PLoS One 2017;12(9):e0184843 doi: 10.1371/journal.pone.0184843[published Online First: Epub Date]|.

81. Hertzog J, Rehwinkel J. Regulation and inhibition of the DNA sensor cGAS. EMBO Rep 2020:e51345 doi: 10.15252/embr.202051345[published Online First: Epub Date]|.

82. Rice AC, Keeney PM, Algarzae NK, Ladd AC, Thomas RR, Bennett JP, Jr. Mitochondrial DNA copy numbers in pyramidal neurons are decreased and mitochondrial biogenesis transcriptome signaling is disrupted in Alzheimer’s disease hippocampi. J Alzheimers Dis 2014;40(2):319-30 doi: 10.3233/JAD-131715[published Online First: Epub Date]|.

83. Arkun K, Rice AC, Bennett JP. Effect of Lewy Bodies on Mitochondrial DNA Copy Numbers and Deletion Burden in Parkinson’s Disease Substantia nigra Neurons. Journal of Alzheimer’s Disease & Parkinsonism 2015;05(01) doi: 10.4172/2161-0460.1000175.

84. Cui J, Wang L, Ren X, Zhang Y, Zhang H. LRPPRC: A Multifunctional Protein Involved in Energy Metabolism and Human Disease. Front Physiol 2019;10:595 doi: 10.3389/fphys.2019.00595[published Online First: Epub Date]|.

85. Ruzzenente B, Metodiev MD, Wredenberg A, et al. LRPPRC is necessary for polyadenylation and coordination of translation of mitochondrial mRNAs. EMBO J 2012;31(2):443-56 doi: 10.1038/emboj.2011.392[published Online First: Epub Date]|.

86. Riley JS, Tait SW. Mitochondrial DNA in inflammation and immunity. EMBO Rep 2020;21(4):e49799 doi: 10.15252/embr.201949799[published Online First: Epub Date]|.

87. Rice AC, Ladd AC, Bennett JP, Jr. Postmortem Alzheimer’s Disease Hippocampi Show Oxidative Phosphorylation Gene Expression Opposite that of Isolated Pyramidal Neurons. J Alzheimers Dis 2015;45(4):1051-9 doi: 10.3233/JAD-142937[published Online First: Epub Date]|.