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Kugler BA, Lysaker CR, Franczak E, Hauger BM, Csikos V, Stopperan JA, Allen JA, Stanford JA, Koch LG, Britton SL, Thyfault JP, Wilkins HM. Intrinsic aerobic capacity modulates Alzheimer's disease pathological hallmarks, brain mitochondrial function and proteome during aging. GeroScience 2024; 46:4955-4967. [PMID: 38867031 PMCID: PMC11336007 DOI: 10.1007/s11357-024-01248-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Accepted: 06/06/2024] [Indexed: 06/14/2024] Open
Abstract
Low aerobic capacity is strongly associated with all-cause mortality and risk for Alzheimer's disease (AD). Individuals with early dementia and AD have lower aerobic capacity compared to age-matched controls. The mechanism by which aerobic capacity influences AD risk is unknown but is likely mediated by sexual dimorphism and tissue-level differences in mitochondrial energetics. Here, we used rats selectively bred for large differences in intrinsic aerobic exercise capacity. Brain tissue from 18-month and 24-month-old female and male low-capacity runner (LCR) and high-capacity runner (HCR) rats were analyzed for markers of mitochondrial function and AD-associated pathologies. LCR rats, irrespective of sex, exhibited a greater increase in brain amyloid beta (Aβ42) and tau hyperphosphorylation (pTauthr181/total tau) with aging. In female LCR rats, brain mitochondrial respiration at states 3, 4, and FCCP-induced uncoupling, when stimulated with pyruvate/malate, was reduced at 18 and 24 months, leading to lower ATP-linked mitochondrial respiration compared to mitochondria from HCR rats. Male LCR rats also showed reduced complex II-stimulated mitochondrial respiration (succinate + rotenone) at 24 months compared to HCR rats. Differences in mitochondrial respiration were associated with tau hyperphosphorylation and Aβ42 alterations in both HCR and LCR strains. Proteomic analysis unveiled a distinct difference in the mitochondrial proteome, wherein female LCR rats displayed diminished mitochondrial translation and oxidative phosphorylation (OXPHOS) proteins at 18 months compared to female HCR rats. Conversely, male LCR rats exhibited increased OXPHOS protein abundance but reduced tricarboxylic acid (TCA) cycle proteins compared to male HCR rats. These findings underscore a robust association between intrinsic aerobic exercise capacity, brain mitochondrial function, and AD pathologies during aging.
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Affiliation(s)
- Benjamin A Kugler
- University of Kansas Medical Center Department of Cell Biology and Physiology and Internal Medicine, Kansas City, KS, USA
| | - Colton R Lysaker
- University of Kansas Alzheimer's Disease Center and Department of Neurology, Kansas City, KS, USA
| | - Edziu Franczak
- University of Kansas Medical Center Department of Cell Biology and Physiology and Internal Medicine, Kansas City, KS, USA
| | - Brittany M Hauger
- University of Kansas Alzheimer's Disease Center and Department of Neurology, Kansas City, KS, USA
| | - Vivien Csikos
- University of Kansas Alzheimer's Disease Center and Department of Neurology, Kansas City, KS, USA
| | - Julia A Stopperan
- University of Kansas Alzheimer's Disease Center and Department of Neurology, Kansas City, KS, USA
| | - Julie A Allen
- University of Kansas Medical Center Department of Cell Biology and Physiology and Internal Medicine, Kansas City, KS, USA
| | - John A Stanford
- University of Kansas Medical Center Department of Cell Biology and Physiology and Internal Medicine, Kansas City, KS, USA
| | - Lauren G Koch
- Department of Physiology and Pharmacology, College of Medicine and Life Sciences, The University of Toledo, Toledo, OH, USA
| | - Steven L Britton
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - John P Thyfault
- University of Kansas Alzheimer's Disease Center and Department of Neurology, Kansas City, KS, USA
- University of Kansas Medical Center Department of Cell Biology and Physiology and Internal Medicine, Kansas City, KS, USA
- Research Service, Kansas City VA Medical Center Department of Veterans Affairs, University of Kansas Diabetes Center, Kansas City, KS, USA
- University of Kansas Medical Center Department of Molecular Biology and Biochemistry, Kansas City, KS, USA
| | - Heather M Wilkins
- University of Kansas Alzheimer's Disease Center and Department of Neurology, Kansas City, KS, USA.
- University of Kansas Medical Center Department of Molecular Biology and Biochemistry, Kansas City, KS, USA.
- Department of Neurology University of Kansas Medical Center, Kansas City, KS, USA.
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Zeng S, Zhu W, Luo Z, Wu K, Lu Z, Li X, Wang W, Hu W, Qin Y, Chen W, Yi L, Fan S, Chen J. Role of OGDH in Atophagy-IRF3-IFN-β pathway during classical swine fever virus infection. Int J Biol Macromol 2023; 249:126443. [PMID: 37604413 DOI: 10.1016/j.ijbiomac.2023.126443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 08/23/2023]
Abstract
Classical swine fever (CSF) is a severe infectious disease caused by the classical swine fever virus (CSFV) that poses significant challenges to the swine industry. α-ketoglutarate dehydrogenase (OGDH), the first rate-limiting enzyme of the tricarboxylic acid (TCA) cycle, catalyzes α-ketoglutarate (α-KG) to succinyl-CoA, playing a crucial role in glycometabolism. Our previous studies showed that CSFV disrupts the TCA cycle, resulting in α-KG accumulation. However, the interplay between CSFV and OGDH remains unclear. In this study, we found that CSFV significantly reduces OGDH protein levels and promotes α-KG secretion through OGDH in PK-15 cells. Furthermore, we observed CSFV C protein interacts with OGDH and revealed that CSFV utilizes NDP52/NBR1 to target OGDH protein degradation in the autophagy-lysosome pathway. We also unveiled that OGDH overexpression inhibits CSFV proliferation, whereas OGDH knockdown increases CSFV proliferation. Further investigation into the mechanisms of OGDH on CSFV replication revealed that OGDH regulates the AMPK-mTOR-autophagy pathway. Additionally, using the autophagy agonist/inhibitor, rapamycin/3-MA, we observed that OGDH modulates autophagy to regulate the IRF3-IFN-β network and CSFV replication. These findings shed light on the role of OGDH in CSFV infection and host metabolism, promoting the development of innovative strategies for combating CSFV and other viral infections via targeting metabolic pathways.
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Affiliation(s)
- Sen Zeng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Wenhui Zhu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Zipeng Luo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Keke Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Zhimin Lu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Xiaowen Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Weijun Wang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Wenshuo Hu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Yuwei Qin
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Wenxian Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Lin Yi
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Shuangqi Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China.
| | - Jinding Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China; Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China.
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Mitochondrial DNA population variation is not associated with Alzheimer's in the Japanese population: A consistent finding across global populations. PLoS One 2022; 17:e0276169. [PMID: 36264923 PMCID: PMC9584534 DOI: 10.1371/journal.pone.0276169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 10/02/2022] [Indexed: 11/06/2022] Open
Abstract
Several mitochondrial DNA (mtDNA) haplogroup association studies have suggested that common mtDNA variants are associated with multifactorial diseases, including Alzheimer’s disease (AD). However, such studies have also produced conflicting results. A new mtDNA association model, the ‘variant load model’ (VLM), has been applied to multiple disease phenotypes. Application of the VLM in a 2017 study failed to find different variant loads in AD patients compared to controls, in two cohorts of European origin. The study also suggested a lower variant load in healthy elderly individuals, but could offer no replicate cohort to support this observation. Here, the VLM is applied to Japanese mtDNA sequences; in doing so, we explored the role of mtDNA variation in AD and ageing in a different global population. Consistent with the previous findings using the VLM in two populations of European origin, we found no evidence for an association between rarer, non-haplogroup associated variation and the development of AD. However, the result in the context of ageing that suggested those with fewer mildly deleterious mutations might undergo healthier ageing, was not replicated. In contrast to our previous study, our present results suggest that those living to advanced old age may harbour more mildly deleterious mtDNA variations. Importantly our analysis showed this finding is not primarily being driven by many rare population variants dispersed across the mtDNA, but by a few more frequent variants with high MutPred scores. It is suggested the variants in question do not exert a mildly deleterious effect in their most frequent haplogroup context.
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Mitochondrial function and Aβ in Alzheimer's disease postmortem brain. Neurobiol Dis 2022; 171:105781. [PMID: 35667615 DOI: 10.1016/j.nbd.2022.105781] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/15/2022] [Accepted: 05/31/2022] [Indexed: 10/18/2022] Open
Abstract
INTRODUCTION Mitochondrial dysfunction is observed in Alzheimer's disease (AD). However, the relationship between functional mitochondrial deficits and AD pathologies is not well established in human subjects. METHODS Post-mortem human brain tissue from 11 non-demented (ND) and 12 AD subjects was used to examine mitochondrial electron transport chain (ETC) function. Data were analyzed by neuropathology diagnosis and Apolipoprotein E (APOE) genotype. Relationships between AD pathology and mitochondrial function were determined. RESULTS AD subjects had reductions in brain cytochrome oxidase (COX) function and complex II Vmax. APOE ε4 carriers had COX, complex II and III deficits. AD subjects had reduced expression of Complex I-III ETC proteins, no changes were observed in APOE ε4 carriers. No correlation between p-Tau Thr 181 and mitochondrial outcomes was observed, although brains from non-demented subjects demonstrated positive correlations between Aβ concentration and COX Vmax. DISCUSSION These data support a dysregulated relationship between brain mitochondrial function and Aβ pathology in AD.
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Bhatia S, Rawal R, Sharma P, Singh T, Singh M, Singh V. Mitochondrial Dysfunction in Alzheimer's Disease: Opportunities for Drug Development. Curr Neuropharmacol 2022; 20:675-692. [PMID: 33998995 PMCID: PMC9878959 DOI: 10.2174/1570159x19666210517114016] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/24/2021] [Accepted: 04/28/2021] [Indexed: 11/22/2022] Open
Abstract
Alzheimer's disease (AD) is one of the major reasons for 60-80% cases of senile dementia occurring as a result of the accumulation of plaques and tangles in the hippocampal and cortical neurons of the brain leading to neurodegeneration and cell death. The other pathological features of AD comprise abnormal microvasculature, network abnormalities, interneuronal dysfunction, increased β-amyloid production and reduced clearance, increased inflammatory response, elevated production of reactive oxygen species, impaired brain metabolism, hyperphosphorylation of tau, and disruption of acetylcholine signaling. Among all these pathologies, Mitochondrial Dysfunction (MD), regardless of it being an inciting insult or a consequence of the alterations, is related to all the associated AD pathologies. Observed altered mitochondrial morphology, distribution and movement, increased oxidative stress, dysregulation of enzymes involved in mitochondrial functioning, impaired brain metabolism, and impaired mitochondrial biogenesis in AD subjects suggest the involvement of mitochondrial malfunction in the progression of AD. Here, various pre-clinical and clinical evidence establishing MD as a key mediator in the progression of neurodegeneration in AD are reviewed and discussed with an aim to foster future MD based drug development research for the management of AD.
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Affiliation(s)
- Shiveena Bhatia
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Rishi Rawal
- School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India
| | - Pratibha Sharma
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Tanveer Singh
- Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, Punjab, India
| | - Manjinder Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India;,Address correspondence to this author at the Chitkara College of Pharmacy, Chitkara University, Punjab, India; E-mails: ;
| | - Varinder Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India;,Address correspondence to this author at the Chitkara College of Pharmacy, Chitkara University, Punjab, India; E-mails: ;
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6
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Austad SN, Ballinger S, Buford TW, Carter CS, Smith DL, Darley-Usmar V, Zhang J. Targeting whole body metabolism and mitochondrial bioenergetics in the drug development for Alzheimer's disease. Acta Pharm Sin B 2022; 12:511-531. [PMID: 35256932 PMCID: PMC8897048 DOI: 10.1016/j.apsb.2021.06.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/26/2021] [Accepted: 06/16/2021] [Indexed: 02/07/2023] Open
Abstract
Aging is by far the most prominent risk factor for Alzheimer's disease (AD), and both aging and AD are associated with apparent metabolic alterations. As developing effective therapeutic interventions to treat AD is clearly in urgent need, the impact of modulating whole-body and intracellular metabolism in preclinical models and in human patients, on disease pathogenesis, have been explored. There is also an increasing awareness of differential risk and potential targeting strategies related to biological sex, microbiome, and circadian regulation. As a major part of intracellular metabolism, mitochondrial bioenergetics, mitochondrial quality-control mechanisms, and mitochondria-linked inflammatory responses have been considered for AD therapeutic interventions. This review summarizes and highlights these efforts.
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Key Words
- ACE2, angiotensin I converting enzyme (peptidyl-dipeptidase A) 2
- AD, Alzheimer's disease
- ADP, adenosine diphosphate
- ADRD, AD-related dementias
- Aβ, amyloid β
- CSF, cerebrospinal fluid
- Circadian regulation
- DAMPs
- DAMPs, damage-associated molecular patterns
- Diabetes
- ER, estrogen receptor
- ETC, electron transport chain
- FCCP, trifluoromethoxy carbonylcyanide phenylhydrazone
- FPR-1, formyl peptide receptor 1
- GIP, glucose-dependent insulinotropic polypeptide
- GLP-1, glucagon-like peptide-1
- HBP, hexoamine biosynthesis pathway
- HTRA, high temperature requirement A
- Hexokinase biosynthesis pathway
- I3A, indole-3-carboxaldehyde
- IRF-3, interferon regulatory factor 3
- LC3, microtubule associated protein light chain 3
- LPS, lipopolysaccharide
- LRR, leucine-rich repeat
- MAVS, mitochondrial anti-viral signaling
- MCI, mild cognitive impairment
- MRI, magnetic resonance imaging
- MRS, magnetic resonance spectroscopy
- Mdivi-1, mitochondrial division inhibitor 1
- Microbiome
- Mitochondrial DNA
- Mitochondrial electron transport chain
- Mitochondrial quality control
- NLRP3, leucine-rich repeat (LRR)-containing protein (NLR)-like receptor family pyrin domain containing 3
- NOD, nucleotide-binding oligomerization domain
- NeuN, neuronal nuclear protein
- PET, fluorodeoxyglucose (FDG)-positron emission tomography
- PKA, protein kinase A
- POLβ, the base-excision repair enzyme DNA polymerase β
- ROS, reactive oxygen species
- Reactive species
- SAMP8, senescence-accelerated mice
- SCFAs, short-chain fatty acids
- SIRT3, NAD-dependent deacetylase sirtuin-3
- STING, stimulator of interferon genes
- STZ, streptozotocin
- SkQ1, plastoquinonyldecyltriphenylphosphonium
- T2D, type 2 diabetes
- TCA, Tricarboxylic acid
- TLR9, toll-like receptor 9
- TMAO, trimethylamine N-oxide
- TP, tricyclic pyrone
- TRF, time-restricted feeding
- cAMP, cyclic adenosine monophosphate
- cGAS, cyclic GMP/AMP synthase
- hAPP, human amyloid precursor protein
- hPREP, human presequence protease
- i.p., intraperitoneal
- mTOR, mechanistic target of rapamycin
- mtDNA, mitochondrial DNA
- αkG, alpha-ketoglutarate
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Affiliation(s)
- Steven N. Austad
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Scott Ballinger
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Thomas W. Buford
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Christy S. Carter
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Daniel L. Smith
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Victor Darley-Usmar
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Jianhua Zhang
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Troutwine BR, Hamid L, Lysaker CR, Strope TA, Wilkins HM. Apolipoprotein E and Alzheimer's disease. Acta Pharm Sin B 2022; 12:496-510. [PMID: 35256931 PMCID: PMC8897057 DOI: 10.1016/j.apsb.2021.10.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/30/2021] [Accepted: 10/07/2021] [Indexed: 12/14/2022] Open
Abstract
Genetic variation in apolipoprotein E (APOE) influences Alzheimer's disease (AD) risk. APOE ε4 alleles are the strongest genetic risk factor for late onset sporadic AD. The AD risk is dose dependent, as those carrying one APOE ε4 allele have a 2-3-fold increased risk, while those carrying two ε4 alleles have a 10-15-fold increased risk. Individuals carrying APOE ε2 alleles have lower AD risk and those carrying APOE ε3 alleles have neutral risk. APOE is a lipoprotein which functions in lipid transport, metabolism, and inflammatory modulation. Isoform specific effects of APOE within the brain include alterations to Aβ, tau, neuroinflammation, and metabolism. Here we review the association of APOE with AD, the APOE isoform specific effects within brain and periphery, and potential therapeutics.
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Affiliation(s)
- Benjamin R. Troutwine
- Department of Neurology University of Kansas Medical Center, Kansas City, KS 66160, USA
- University of Kansas Alzheimer's Disease Center, Kansas City, KS 66160, USA
| | - Laylan Hamid
- University of Kansas Alzheimer's Disease Center, Kansas City, KS 66160, USA
| | - Colton R. Lysaker
- University of Kansas Alzheimer's Disease Center, Kansas City, KS 66160, USA
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Taylor A. Strope
- University of Kansas Alzheimer's Disease Center, Kansas City, KS 66160, USA
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Heather M. Wilkins
- Department of Neurology University of Kansas Medical Center, Kansas City, KS 66160, USA
- University of Kansas Alzheimer's Disease Center, Kansas City, KS 66160, USA
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
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Swerdlow NS, Wilkins HM. Mitophagy and the Brain. Int J Mol Sci 2020; 21:ijms21249661. [PMID: 33352896 PMCID: PMC7765816 DOI: 10.3390/ijms21249661] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 02/06/2023] Open
Abstract
Stress mechanisms have long been associated with neuronal loss and neurodegenerative diseases. The origin of cell stress and neuronal loss likely stems from multiple pathways. These include (but are not limited to) bioenergetic failure, neuroinflammation, and loss of proteostasis. Cells have adapted compensatory mechanisms to overcome stress and circumvent death. One mechanism is mitophagy. Mitophagy is a form of macroautophagy, were mitochondria and their contents are ubiquitinated, engulfed, and removed through lysosome degradation. Recent studies have implicated mitophagy dysregulation in several neurodegenerative diseases and clinical trials are underway which target mitophagy pathways. Here we review mitophagy pathways, the role of mitophagy in neurodegeneration, potential therapeutics, and the need for further study.
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Affiliation(s)
- Natalie S. Swerdlow
- University of Kansas Alzheimer’s Disease Center, University of Kansas, Kansas City, KS 66160, USA;
| | - Heather M. Wilkins
- University of Kansas Alzheimer’s Disease Center, University of Kansas, Kansas City, KS 66160, USA;
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS 66160, USA
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
- Correspondence:
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Maldonado C, Vázquez M, Fagiolino P. Potential Therapeutic Role of Carnitine and Acetylcarnitine in Neurological Disorders. Curr Pharm Des 2020; 26:1277-1285. [PMID: 32048954 DOI: 10.2174/1381612826666200212114038] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 01/30/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND Current therapy of neurological disorders has several limitations. Although a high number of drugs are clinically available, several subjects do not achieve full symptomatic remission. In recent years, there has been an increasing interest in the therapeutic potential of L-carnitine (LCAR) and acetyl-L-carnitine (ALCAR) because of the multiplicity of actions they exert in energy metabolism, as antioxidants, neuromodulators and neuroprotectors. They also show excellent safety and tolerability profile. OBJECTIVE To assess the role of LCAR and ALCAR in neurological disorders. METHODS A meticulous review of the literature was conducted in order to establish the linkage between LCAR and ALCAR and neurological diseases. RESULTS LCAR and ALCAR mechanisms and effects were studied for Alzheimer's disease, depression, neuropathic pain, bipolar disorder, Parkinson's disease and epilepsy in the elderly. Both substances exert their actions mainly on primary metabolism, enhancing energy production, through β-oxidation, and the ammonia elimination via urea cycle promotion. These systemic actions impact positively on the Central Nervous System state, as Ammonia and energy depletion seem to underlie most of the neurotoxic events, such as inflammation, oxidative stress, membrane degeneration, and neurotransmitters disbalances, present in neurological disorders, mainly in the elderly. The impact on bipolar disorder is controversial. LCAR absorption seems to be impaired in the elderly due to the decrease of active transportation; therefore, ALCAR seems to be the more effective option to administer. CONCLUSION ALCAR emerges as a simple, economical and safe adjuvant option in order to impair the progression of most neurological disorders.
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Affiliation(s)
- Cecilia Maldonado
- Biopharmaceutics and Therapeutics, Pharmaceutical Sciences Department, Faculty of Chemistry, Universidad de la Republica, Montevideo, Uruguay
| | - Marta Vázquez
- Biopharmaceutics and Therapeutics, Pharmaceutical Sciences Department, Faculty of Chemistry, Universidad de la Republica, Montevideo, Uruguay
| | - Pietro Fagiolino
- Biopharmaceutics and Therapeutics, Pharmaceutical Sciences Department, Faculty of Chemistry, Universidad de la Republica, Montevideo, Uruguay
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Berlanga-Acosta J, Guillén-Nieto G, Rodríguez-Rodríguez N, Bringas-Vega ML, García-del-Barco-Herrera D, Berlanga-Saez JO, García-Ojalvo A, Valdés-Sosa MJ, Valdés-Sosa PA. Insulin Resistance at the Crossroad of Alzheimer Disease Pathology: A Review. Front Endocrinol (Lausanne) 2020; 11:560375. [PMID: 33224105 PMCID: PMC7674493 DOI: 10.3389/fendo.2020.560375] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 08/13/2020] [Indexed: 12/16/2022] Open
Abstract
Insulin plays a major neuroprotective and trophic function for cerebral cell population, thus countering apoptosis, beta-amyloid toxicity, and oxidative stress; favoring neuronal survival; and enhancing memory and learning processes. Insulin resistance and impaired cerebral glucose metabolism are invariantly reported in Alzheimer's disease (AD) and other neurodegenerative processes. AD is a fatal neurodegenerative disorder in which progressive glucose hypometabolism parallels to cognitive impairment. Although AD may appear and progress in virtue of multifactorial nosogenic ingredients, multiple interperpetuative and interconnected vicious circles appear to drive disease pathophysiology. The disease is primarily a metabolic/energetic disorder in which amyloid accumulation may appear as a by-product of more proximal events, especially in the late-onset form. As a bridge between AD and type 2 diabetes, activation of c-Jun N-terminal kinase (JNK) pathway with the ensued serine phosphorylation of the insulin response substrate (IRS)-1/2 may be at the crossroads of insulin resistance and its subsequent dysmetabolic consequences. Central insulin axis bankruptcy translates in neuronal vulnerability and demise. As a link in the chain of pathogenic vicious circles, mitochondrial dysfunction, oxidative stress, and peripheral/central immune-inflammation are increasingly advocated as major pathology drivers. Pharmacological interventions addressed to preserve insulin axis physiology, mitochondrial biogenesis-integral functionality, and mitophagy of diseased organelles may attenuate the adjacent spillover of free radicals that further perpetuate mitochondrial damages and catalyze inflammation. Central and/or peripheral inflammation may account for a local flood of proinflammatory cytokines that along with astrogliosis amplify insulin resistance, mitochondrial dysfunction, and oxidative stress. All these elements are endogenous stressor, pro-senescent factors that contribute to JNK activation. Taken together, these evidences incite to identify novel multi-mechanistic approaches to succeed in ameliorating this pandemic affliction.
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Affiliation(s)
- Jorge Berlanga-Acosta
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China
- Tissue Repair and Cytoprotection Research Group, Center for Genetic Engineering and Biotechnology, Havana, Cuba
| | - Gerardo Guillén-Nieto
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China
- Tissue Repair and Cytoprotection Research Group, Center for Genetic Engineering and Biotechnology, Havana, Cuba
| | - Nadia Rodríguez-Rodríguez
- Tissue Repair and Cytoprotection Research Group, Center for Genetic Engineering and Biotechnology, Havana, Cuba
| | - Maria Luisa Bringas-Vega
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China
- Cuban Neurosciences Center, Cubanacan, Havana, Cuba
| | | | - Jorge O. Berlanga-Saez
- Applied Mathematics Department, Institute of Mathematics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ariana García-Ojalvo
- Tissue Repair and Cytoprotection Research Group, Center for Genetic Engineering and Biotechnology, Havana, Cuba
| | - Mitchell Joseph Valdés-Sosa
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China
- Cuban Neurosciences Center, Cubanacan, Havana, Cuba
| | - Pedro A. Valdés-Sosa
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, University of Electronic Science and Technology of China, Chengdu, China
- Cuban Neurosciences Center, Cubanacan, Havana, Cuba
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Mohajeri M, Martín-Jiménez C, Barreto GE, Sahebkar A. Effects of estrogens and androgens on mitochondria under normal and pathological conditions. Prog Neurobiol 2019; 176:54-72. [DOI: 10.1016/j.pneurobio.2019.03.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 02/23/2019] [Accepted: 03/05/2019] [Indexed: 02/06/2023]
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12
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Wilkins HM, Weidling IW, Ji Y, Swerdlow RH. Mitochondria-Derived Damage-Associated Molecular Patterns in Neurodegeneration. Front Immunol 2017; 8:508. [PMID: 28491064 PMCID: PMC5405073 DOI: 10.3389/fimmu.2017.00508] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 04/12/2017] [Indexed: 12/21/2022] Open
Abstract
Inflammation is increasingly implicated in neurodegenerative disease pathology. As no acquired pathogen appears to drive this inflammation, the question of what does remains. Recent advances indicate damage-associated molecular pattern (DAMP) molecules, which are released by injured and dying cells, can cause specific inflammatory cascades. Inflammation, therefore, can be endogenously induced. Mitochondrial components induce inflammatory responses in several pathological conditions. Due to evidence such as this, a number of mitochondrial components, including mitochondrial DNA, have been labeled as DAMP molecules. In this review, we consider the contributions of mitochondrial-derived DAMPs to inflammation observed in neurodegenerative diseases.
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Affiliation(s)
- Heather M Wilkins
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA.,University of Kansas Alzheimer's Disease Center, Kansas City, KS, USA
| | - Ian W Weidling
- University of Kansas Alzheimer's Disease Center, Kansas City, KS, USA.,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Yan Ji
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA.,University of Kansas Alzheimer's Disease Center, Kansas City, KS, USA
| | - Russell H Swerdlow
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA.,University of Kansas Alzheimer's Disease Center, Kansas City, KS, USA.,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA.,Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, USA
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Alterations in Cytosolic and Mitochondrial [U- 13C]Glucose Metabolism in a Chronic Epilepsy Mouse Model. eNeuro 2017; 4:eN-NWR-0341-16. [PMID: 28303258 PMCID: PMC5343280 DOI: 10.1523/eneuro.0341-16.2017] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 01/10/2017] [Accepted: 01/16/2017] [Indexed: 01/17/2023] Open
Abstract
Temporal lobe epilepsy is a common form of adult epilepsy and shows high resistance to treatment. Increasing evidence has suggested that metabolic dysfunction contributes to the development of seizures, with previous studies indicating impairments in brain glucose metabolism. Here we aim to elucidate which pathways involved in glucose metabolism are impaired, by tracing the hippocampal metabolism of injected [U-13C]glucose (i.p.) during the chronic stage of the pilocarpine-status epilepticus mouse model of epilepsy. The enrichment of 13C in the intermediates of glycolysis and the TCA cycle were quantified in hippocampal extracts using liquid chromatography–tandem mass spectroscopy, along with the measurement of the activities of enzymes in each pathway. We show that there is reduced incorporation of 13C in the intermediates of glycolysis, with the percentage enrichment of all downstream intermediates being highly correlated with those of glucose 6-phosphate. Furthermore, the activities of all enzymes in this pathway including hexokinase and phosphofructokinase were unaltered, suggesting that glucose uptake is reduced in this model without further impairments in glycolysis itself. The key findings were 33% and 55% losses in the activities of pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase, respectively, along with reduced 13C enrichment in TCA cycle intermediates. This lower 13C enrichment is best explained in part by the reduced enrichment in glycolytic intermediates, whereas the reduction of key TCA cycle enzyme activity indicates that TCA cycling is also impaired in the hippocampal formation. Together, these data suggest that multitarget approaches may be necessary to restore metabolism in the epileptic brain.
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Hu H, Li M. Mitochondria-targeted antioxidant mitotempo protects mitochondrial function against amyloid beta toxicity in primary cultured mouse neurons. Biochem Biophys Res Commun 2016; 478:174-180. [PMID: 27444386 DOI: 10.1016/j.bbrc.2016.07.071] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 07/17/2016] [Indexed: 11/27/2022]
Abstract
Mitochondrial defects including excess reactive oxygen species (ROS) production and compromised ATP generation are featured pathology in Alzheimer's disease (AD). Amyloid beta (Aβ)-mediated mitochondrial ROS overproduction disrupts intra-neuronal Redox balance, in turn exacerbating mitochondrial dysfunction leading to neuronal injury. Previous studies have found the beneficial effects of mitochondria-targeted antioxidants in preventing mitochondrial dysfunction and neuronal injury in AD animal and cell models, suggesting that mitochondrial ROS scavengers hold promise for the treatment of this neurological disorder. In this study, we have determined that mitotempo, a novel mitochondria-targeted antioxidant protects mitochondrial function from the toxicity of Aβ in primary cultured neurons. Our results showed that Aβ-promoted mitochondrial superoxide production and neuronal lipid oxidation were significantly suppressed by the application of mitotempo. Moreover, mitotempo also demonstrated protective effects on mitochondrial bioenergetics evidenced by preserved mitochondrial membrane potential, cytochrome c oxidase activity as well as ATP production. In addition, the Aβ-induced mitochondrial DNA (mtDNA) depletion and decreased expression levels of mtDNA replication-related DNA polymerase gamma (DNA pol γ) and Twinkle were substantially mitigated by mitotempo. Therefore, our study suggests that elimination of excess mitochondrial ROS rescues mitochondrial function in Aβ-insulted neruons; and mitotempo has the potential to be a promising therapeutic agent to protect mitochondrial and neuronal function in AD.
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Affiliation(s)
- Hongtao Hu
- Department of Neurology, Beijing Jishuitan Hospital, 31 Xinjiekou E Rd, Xicheng, Beijing, 100035, China.
| | - Mo Li
- Department of Neurology, Beijing Jishuitan Hospital, 31 Xinjiekou E Rd, Xicheng, Beijing, 100035, China
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15
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Glycolytic enzyme upregulation and numbness of mitochondrial activity characterize the early phase of apoptosis in cerebellar granule cells. Apoptosis 2015; 20:10-28. [PMID: 25351440 DOI: 10.1007/s10495-014-1049-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Alzheimer's disease (AD) and cancer proceed via one or more common molecular mechanisms: a metabolic shift from oxidative phosphorylation to glycolysis-corresponding to the activation of the Warburg effect-occurs in both diseases. The findings reported in this paper demonstrate that, in the early phase of apoptosis, glucose metabolism is enhanced, i.e. key proteins which internalize and metabolize glucose-glucose transporter, hexokinase and phosphofructokinase-are up-regulated, in concomitance with a parallel decrease in oxygen consumption by mitochondria and increase of L-lactate accumulation. Reversal of the glycolytic phenotype occurs in the presence of dichloroacetate, inhibitor of the pyruvate dehydrogenase kinase enzyme, which speeds up apoptosis of cerebellar granule cells, reawakening mitochondria and then modulating glycolytic enzymes. Loss of the adaptive advantage afforded by aerobic glycolysis, which occurs in the late phase of apoptosis, exacerbates the pathological processes underlying neurodegeneration, leading inevitably the cell to death. In conclusion, the data propose that both aerobic, i.e. Warburg effect, essentially due to the protective numbness of mitochondria, and anaerobic glycolysis, rather due to the mitochondrial impairment, characterize the entire time frame of apoptosis, from the early to the late phase, which mimics the development of AD.
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Wilkins HM, Carl SM, Greenlief ACS, Festoff BW, Swerdlow RH. Bioenergetic dysfunction and inflammation in Alzheimer's disease: a possible connection. Front Aging Neurosci 2014; 6:311. [PMID: 25426068 PMCID: PMC4226164 DOI: 10.3389/fnagi.2014.00311] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 10/23/2014] [Indexed: 11/29/2022] Open
Abstract
Inflammation is observed in Alzheimer’s disease (AD) subject brains. Inflammation-relevant genes are increasingly implicated in AD genetic studies, and inflammatory cytokines to some extent even function as peripheral biomarkers. What underlies AD inflammation is unclear, but no “foreign” agent has been implicated. This suggests that internally produced damage-associated molecular pattern (DAMPs) molecules may drive inflammation in AD. A more complete characterization and understanding of AD-relevant DAMPs could advance our understanding of AD and suggest novel therapeutic strategies. In this review, we consider the possibility that mitochondria, intracellular organelles that resemble bacteria in many ways, trigger and maintain chronic inflammation in AD subjects. Data supporting the possible nexus between AD-associated bioenergetic dysfunction are discussed.
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Affiliation(s)
- Heather M Wilkins
- Department of Neurology, University of Kansas Medical Center , Kansas City, KS , USA ; University of Kansas Alzheimer's Disease Center, University of Kansas Medical Center , Kansas City, KS , USA
| | - Steven M Carl
- University of Kansas Alzheimer's Disease Center, University of Kansas Medical Center , Kansas City, KS , USA
| | - Alison C S Greenlief
- University of Kansas Alzheimer's Disease Center, University of Kansas Medical Center , Kansas City, KS , USA
| | - Barry W Festoff
- Department of Neurology, University of Kansas Medical Center , Kansas City, KS , USA ; Department of Pharmacology, University of Kansas Medical Center , Kansas City, KS , USA ; Department of Molecular and Integrative Physiology, University of Kansas Medical Center , Kansas City, KS , USA ; pHLOGISTIX Neurodiagnostics , Lenexa, KS , USA
| | - Russell H Swerdlow
- Department of Neurology, University of Kansas Medical Center , Kansas City, KS , USA ; University of Kansas Alzheimer's Disease Center, University of Kansas Medical Center , Kansas City, KS , USA ; Department of Molecular and Integrative Physiology, University of Kansas Medical Center , Kansas City, KS , USA ; Department of Biochemistry and Molecular Biology, University of Kansas Medical Center , Kansas City, KS , USA
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Pettegrew JW, McClure RJ. Acetyl-l-carnitine as a possible therapy for Alzheimer’s disease. Expert Rev Neurother 2014; 2:647-54. [DOI: 10.1586/14737175.2.5.647] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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18
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Wang X, Wang LP, Tang H, Shan WY, Wang X, Liu D, Wu YY, Tian Q, Wang JZ, Zhu LQ. Acetyl-L-carnitine rescues scopolamine-induced memory deficits by restoring insulin-like growth factor II via decreasing p53 oxidation. Neuropharmacology 2013; 76 Pt A:80-7. [PMID: 24012657 DOI: 10.1016/j.neuropharm.2013.08.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 08/19/2013] [Accepted: 08/22/2013] [Indexed: 10/26/2022]
Abstract
Alzheimer's disease (AD) is characterized by the cholinergic neurons loss and impairments of learning and memory. Scopolamine is common used to imitate AD pathological features and also causes an obvious oxidative stress. In this study, we found that intraperitoneal administration of supplementary acetyl-L-carnitine partially reverses the learning and memory defects induced by scopolamine. We also found that acetyl-L-carnitine reverses the impairment of long-term potentiation, dendritic abnormalities, and the impaired recruitment of synaptic protein. The beneficial effects of acetyl-L-carnitine may occur through amelioration of oxidative stress because it effectively decreases the levels of oxidative products and increases the activity of superoxide dismutase; this leads to a recovery in the suppressed activity of p53 caused oxidative stimuli, which in turn restores levels of insulin-like growth factor II, an important hormone for learning and memory. Our study provides the first evidence of the potential utility of acetyl-L-carnitine in treating the synaptic disorders prevalent in AD and other neurodegenerative diseases. This article is part of the Special Issue entitled 'The Synaptic Basis of Neurodegenerative Disorders'.
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Affiliation(s)
- Xiang Wang
- Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, PR China
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McLain AL, Cormier PJ, Kinter M, Szweda LI. Glutathionylation of α-ketoglutarate dehydrogenase: the chemical nature and relative susceptibility of the cofactor lipoic acid to modification. Free Radic Biol Med 2013; 61:161-9. [PMID: 23567190 PMCID: PMC3883985 DOI: 10.1016/j.freeradbiomed.2013.03.020] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Revised: 03/09/2013] [Accepted: 03/25/2013] [Indexed: 01/13/2023]
Abstract
α-Ketoglutarate dehydrogenase (KGDH) is reversibly inhibited when rat heart mitochondria are exposed to hydrogen peroxide (H2O2). H2O2-induced inhibition occurs through the formation of a mixed disulfide between a protein sulfhydryl and glutathione. Upon consumption of H2O2, glutaredoxin can rapidly remove glutathione, resulting in regeneration of enzyme activity. KGDH is a key regulatory site within the Krebs cycle. Glutathionylation of the enzyme may therefore represent an important means to control mitochondrial function in response to oxidative stress. We have previously provided indirect evidence that glutathionylation occurs on lipoic acid, a cofactor covalently bound to the E2 subunit of KGDH. However, lipoic acid contains two vicinal sulfhydryls and rapid disulfide exchange might be predicted to preclude stable glutathionylation. The current study sought conclusive identification of the site and chemistry of KGDH glutathionylation and factors that control the degree and rate of enzyme inhibition. We present evidence that, upon reaction of free lipoic acid with oxidized glutathione in solution, disulfide exchange occurs rapidly, producing oxidized lipoic acid and reduced glutathione. This prevents the stable formation of a glutathione-lipoic acid adduct. Nevertheless, 1:1 lipoic acid-glutathione adducts are formed on KGDH because the second sulfhydryl on lipoic acid is unable to participate in disulfide exchange in the enzyme's native conformation. The maximum degree of KGDH inhibition that can be achieved by treatment of mitochondria with H2O2 is 50%. Results indicate that this is not due to glutathionylation of a subpopulation of the enzyme but, rather, the unique susceptibility of lipoic acid on a subset of E2 subunits within each enzyme complex. Calcium enhances the rate of glutathionylation by increasing the half-life of reduced lipoic acid during enzyme catalysis. This does not, however, alter the maximal level of inhibition, providing further evidence that specific lipoic acid residues within the E2 complex are susceptible to glutathionylation. These findings offer chemical information necessary for the identification of mechanisms and physiological implications of KGDH glutathionylation.
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Affiliation(s)
- Aaron L McLain
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, OK 73104, USA
| | - Peter J Cormier
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Michael Kinter
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Geriatric Medicine, Reynolds Center on Aging, University of Oklahoma Health Science Center, Oklahoma City, OK 73104, USA
| | - Luke I Szweda
- Free Radical Biology and Aging Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA; Department of Biochemistry and Molecular Biology, University of Oklahoma Health Science Center, Oklahoma City, OK 73104, USA; Department of Geriatric Medicine, Reynolds Center on Aging, University of Oklahoma Health Science Center, Oklahoma City, OK 73104, USA.
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20
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Duarte AI, Moreira PI, Oliveira CR. Insulin in central nervous system: more than just a peripheral hormone. J Aging Res 2012; 2012:384017. [PMID: 22500228 PMCID: PMC3303591 DOI: 10.1155/2012/384017] [Citation(s) in RCA: 179] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 10/12/2011] [Accepted: 11/23/2011] [Indexed: 12/14/2022] Open
Abstract
Insulin signaling in central nervous system (CNS) has emerged as a novel field of research since decreased brain insulin levels and/or signaling were associated to impaired learning, memory, and age-related neurodegenerative diseases. Thus, besides its well-known role in longevity, insulin may constitute a promising therapy against diabetes- and age-related neurodegenerative disorders. More interestingly, insulin has been also faced as the potential missing link between diabetes and aging in CNS, with Alzheimer's disease (AD) considered as the "brain-type diabetes." In fact, brain insulin has been shown to regulate both peripheral and central glucose metabolism, neurotransmission, learning, and memory and to be neuroprotective. And a future challenge will be to unravel the complex interactions between aging and diabetes, which, we believe, will allow the development of efficient preventive and therapeutic strategies to overcome age-related diseases and to prolong human "healthy" longevity. Herewith, we aim to integrate the metabolic, neuromodulatory, and neuroprotective roles of insulin in two age-related pathologies: diabetes and AD, both in terms of intracellular signaling and potential therapeutic approach.
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Affiliation(s)
- Ana I. Duarte
- CNC, Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
| | - Paula I. Moreira
- CNC, Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
- Institute of Physiology, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal
| | - Catarina R. Oliveira
- CNC, Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
- Institute of Biochemistry, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal
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21
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Abstract
Copper has been known to be essential for health for more than three quarters of a century. Myriad experiments with animals reveal that the cardiovascular, musculoskeletal and nervous systems are most sensitive to deficiency. Copper in the Western diet has been decreasing at least since the 1930s; half of the adult population consumes less than the amount recommended in the European Communities and the United Kingdom. At least one fourth of adults consume less than the estimated average requirement published for the United States and Canada. Hundreds of people have been reported in journals about medicine and neurology rather than nutrition to have impaired copper nutriture based on the criteria of low copper concentrations and low activities of enzymes dependent on copper in various fluids and tissues. In contrast, only 46 people have participated in depletion/repletion experiments needed to define requirements. Almost 1000 people have benefited from supplements containing copper in controlled trials. People deficient in copper are being identified increasingly; it is unknown if unusually high requirements or unusually low diets are causal. Alzheimer's disease, ischemic heart disease and osteoporosis are the most likely human illnesses from low copper intakes.
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Affiliation(s)
- Leslie M Klevay
- Department of Internal Medicine, University of North Dakota, School of Medicine and Health Sciences, Grand Forks, ND 58201, United States.
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McLain AL, Szweda PA, Szweda LI. α-Ketoglutarate dehydrogenase: a mitochondrial redox sensor. Free Radic Res 2010; 45:29-36. [PMID: 21110783 DOI: 10.3109/10715762.2010.534163] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
α-Ketoglutarate dehydrogenase (KGDH), a key regulatory enzyme within the Krebs cycle, is sensitive to mitochondrial redox status. Treatment of mitochondria with H₂O₂ results in reversible inhibition of KGDH due to glutathionylation of the cofactor, lipoic acid. Upon consumption of H₂O₂, glutathione is removed by glutaredoxin restoring KGDH activity. Glutathionylation appears to be enzymatically catalysed or require a unique microenvironment. This may represent an antioxidant response, diminishing the flow of electrons to the respiratory chain and protecting sulphydryl residues from oxidative damage. KGDH is, however, also susceptible to oxidative damage. 4-Hydroxy-2-nonenal (HNE), a lipid peroxidation product, reacts with lipoic acid resulting in enzyme inactivation. Evidence indicates that HNE modified lipoic acid is cleaved from KGDH, potentially the first step of a repair process. KGDH is therefore a likely redox sensor, reversibly altering metabolism to reduce oxidative damage and, under severe oxidative stress, acting as a sentinel of mitochondrial viability.
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Affiliation(s)
- Aaron L McLain
- Free Radical Biology and Aging Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA
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23
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Simpkins JW, Yi KD, Yang SH, Dykens JA. Mitochondrial mechanisms of estrogen neuroprotection. Biochim Biophys Acta Gen Subj 2009; 1800:1113-20. [PMID: 19931595 DOI: 10.1016/j.bbagen.2009.11.013] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 11/11/2009] [Accepted: 11/12/2009] [Indexed: 01/11/2023]
Abstract
Mitochondria have become a primary focus in our search not only for the mechanism(s) of neuronal death but also for neuroprotective drugs and therapies that can delay or prevent Alzheimer's disease and other chronic neurodegenerative conditions. This is because mitochrondria play a central role in regulating viability and death of neurons, and mitochondrial dysfunction has been shown to contribute to neuronal death seen in neurodegenerative diseases. In this article, we review the evidence for the role of mitochondria in cell death and neurodegeneration and provide evidence that estrogens have multiple effects on mitochondria that enhance or preserve mitochondrial function during pathologic circumstances such as excitotoxicity, oxidative stress, and others. As such, estrogens and novel non-hormonal analogs have come to figure prominently in our efforts to protect neurons against both acute brain injury and chronic neurodegeneration.
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Affiliation(s)
- James W Simpkins
- Department of Pharmacology & Neuroscience, Institute for Aging and Alzheimer's Disease Research, University of North Texas Health Science Center, Fort Worth, TX, USA.
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Abstract
Proteins, nucleic acids, and lipids can undergo various forms of oxidative modification. In numerous instances, these modifications result in irreversible loss of function. The age-dependent accumulation of oxidatively modified and dysfunctional macromolecules provides the basis for the free radical theory of aging. Pro-oxidants, however, are also capable of catalyzing fully reversible modifications to protein. It is increasingly apparent that these reactions participate in redox-dependent regulation of cell metabolism and response to stress. The adventitious use of free radical species adds complexity to the experimental and theoretical manner in which the free radical theory is to be tested and considered. Elucidation of mechanisms by which reversible oxidative processes are controlled, the components involved, and the metabolic consequences and how they are altered with age will provide new insight on the aging process and attempts to delay the inevitable.
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Simpkins JW, Yang SH, Sarkar SN, Pearce V. Estrogen actions on mitochondria--physiological and pathological implications. Mol Cell Endocrinol 2008; 290:51-9. [PMID: 18571833 PMCID: PMC2737506 DOI: 10.1016/j.mce.2008.04.013] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 04/08/2008] [Accepted: 04/10/2008] [Indexed: 02/07/2023]
Abstract
Estrogens are potent neuroprotective hormones and mitochondria are the site of cellular life-death decisions. As such, it is not surprising that we and others have shown that estrogens have remarkable effects on mitochondrial function. Herein we provide evidence for a primary effect of estrogens on mitochondrial function, achieved in part by the import of estrogen receptor beta (ERbeta) into the mitochondria where it mediates a number of estrogen actions on this vital organelle. ERbeta is imported into the mitochondria, through tethering to cytosolic chaperone protein and/or through direct interaction with mitochondrial import proteins. In the mitochondria, ERbeta can affect transcription of critical mitochondrial genes through the interaction with estrogen response elements (ERE) or through protein-protein interactions with mitochondrially imported transcription factors. The potent effects of estrogens on mitochondrial function, particularly during mitochondrial stress, argues for a role of estrogens in the treatment of mitochondrial defects in chronic neurodegenerative diseases like Alzheimer's disease (AD) and Parkinson's disease (PD) and more acute conditions of mitochondrial compromise, like cerebral ischemia and traumatic brain injury.
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Affiliation(s)
- James W Simpkins
- Department of Pharmacology & Neuroscience, Institute for Aging and Alzheimer's Disease Research, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA.
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Studzinski CM, MacKay WA, Beckett TL, Henderson ST, Murphy MP, Sullivan PG, Burnham WM. Induction of ketosis may improve mitochondrial function and decrease steady-state amyloid-β precursor protein (APP) levels in the aged dog. Brain Res 2008; 1226:209-17. [DOI: 10.1016/j.brainres.2008.06.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Revised: 06/03/2008] [Accepted: 06/03/2008] [Indexed: 01/06/2023]
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Mancuso C, Bates TE, Butterfield DA, Calafato S, Cornelius C, Lorenzo AD, Dinkova Kostova AT, Calabrese V. Natural antioxidants in Alzheimer's disease. Expert Opin Investig Drugs 2007; 16:1921-31. [DOI: 10.1517/13543784.16.12.1921] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Viña J, Lloret A, Vallés SL, Borrás C, Badía MC, Pallardó FV, Sastre J, Alonso MD. Effect of gender on mitochondrial toxicity of Alzheimer's Abeta peptide. Antioxid Redox Signal 2007; 9:1677-90. [PMID: 17822363 DOI: 10.1089/ars.2007.1773] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The aim of this article is to review the role of mitochondria in the pathogenesis of Alzheimer's disease. Additionally, the effect of gender on the incidence of Alzheimer's disease and the pathophysiological mechanisms involved will be discussed. Mitochondria, in the presence of Alzheimer's amyloid-beta peptide, increase the formation of reactive oxygen species which act both as damaging agents and also as signaling molecules. These radicals, in fact, unleash a mechanism involving the liberation of cytochrome c that leads to neuronal apoptosis. Notably, young females appear protected against the mitochondrial toxicity of amyloid-beta, likely due to the upregulation of antioxidant enzymes which occur in females. Estrogens are responsible for this effect. Overall, the findings support the notion that amyloid-beta causes intracellular toxicity via the increased production of oxidant species. Reactive oxygen species generated by mitochondria act as a signal to start the mitochondrial apoptotic pathway. There is a possibility of prevention, and indirect evidence shows that estrogenic compounds (either endogenous estradiol or phytoestrogens such as genistein) may increase the expression of antioxidant enzymes, leading to a lowering of oxidative stress and thus protection against intracellular toxicity of amyloid-beta peptide. These ideas open up the possibility of using phytoestrogens to prevent the onset of Alzheimer's disease. More studies are required to determine whether estrogens and/or phytoestrogens fulfill these expectations.
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Affiliation(s)
- Jose Viña
- Departamento de Fisiología, Facultad de Medicina, Universidad de Valencia, Valencia, Spain.
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29
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Rhein V, Eckert A. Effects of Alzheimer's amyloid-beta and tau protein on mitochondrial function -- role of glucose metabolism and insulin signalling. Arch Physiol Biochem 2007; 113:131-41. [PMID: 17922309 DOI: 10.1080/13813450701572288] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Alzheimer's disease (AD) is the most frequent form of dementia among the elderly and is characterized by neuropathological hallmarks of extracellular amyloid-beta (Abeta) plaques and intracellular neurofibrillary tangles composed of abnormally hyperphosphorylated microtubular protein tau in the brains of AD patients. Of note, current data illustrate a complex interplay between the amyloid and tau pathology during the course of the disease. We hypothesize a direct impact of abnormally phosphorylated tau and Abeta on proteins/enzymes involved in metabolism, respiratory chain function and cellular detoxification. Probably at the level of mitochondria, both Alzheimer proteins exhibit synergistic effects finally leading to/accelerating neurodegenerative mechanisms. Moreover, accumulating evidence that mitochondria failure, reduced glucose utilization and deficient energy metabolism occur already very early in the course of the disease suggests a role of impaired insulin signalling in the pathogenesis of AD. Thus, this review addresses also the question if mitochondrial dysfunction may represent a link between diabetes and AD.
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Affiliation(s)
- Virginie Rhein
- Neurobiology Laboratory, Psychiatric University Clinics Basel, Basel, Switzerland.
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Simpkins JW, Dykens JA. Mitochondrial mechanisms of estrogen neuroprotection. ACTA ACUST UNITED AC 2007; 57:421-30. [PMID: 17512984 DOI: 10.1016/j.brainresrev.2007.04.007] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Revised: 04/20/2007] [Accepted: 04/21/2007] [Indexed: 11/19/2022]
Abstract
Oxidative stress, bioenergetic failure and mitochondrial dysfunction are all implicated in the etiology of neurodegenerative diseases such as Alzheimer's disease (AD). The mitochondrial involvement in neurodegenerative diseases reflects the regulatory role mitochondrial failure plays in both necrotic cell death and apoptosis. The potent feminizing hormone, 17 beta-estradiol (E2), is neuroprotective in a host of cell and animal models of stroke and neurodegenerative diseases. The discovery that 17alpha-estradiol, an isomer of E2, is equally as neuroprotective as E2 yet is >200-fold less active as a hormone, has permitted development of novel, more potent analogs where neuroprotection is independent of hormonal potency. Studies of structure-activity relationships and mitochondrial function have led to a mechanistic model in which these steroidal phenols intercalate into cell membranes where they block lipid peroxidation reactions, and are in turn recycled. Indeed, the parental estrogens and novel analogs stabilize mitochondria under Ca(2+) loading otherwise sufficient to collapse membrane potential. The neuroprotective and mitoprotective potencies for a series of estrogen analogs are significantly correlated, suggesting that these compounds prevent cell death in large measure by maintaining functionally intact mitochondria. This therapeutic strategy is germane not only to sudden mitochondrial failure in acute circumstances, such as during a stroke or myocardial infarction, but also to gradual mitochondrial dysfunction associated with chronic degenerative disorders such as AD.
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Affiliation(s)
- James W Simpkins
- Department of Pharmacology and Neuroscience, Institute for Aging and Alzheimer's Disease Research, University of North Texas Health Science Center, 3500 Camp Bowie Boul., Fort Worth, TX 76102, USA.
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Moreira PI, Santos MS, Seiça R, Oliveira CR. Brain mitochondrial dysfunction as a link between Alzheimer's disease and diabetes. J Neurol Sci 2007; 257:206-14. [PMID: 17316694 DOI: 10.1016/j.jns.2007.01.017] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
It has been argued that in late-onset Alzheimer's disease a disturbance in the control of neuronal glucose metabolism consequent to impaired insulin signalling strongly resembles the pathophysiology of type 2 diabetes in non-neural tissue. The fact that mitochondria are the major generators and direct targets of reactive oxygen species led several investigators to foster the idea that oxidative stress and damage in mitochondria are contributory factors to several disorders including Alzheimer's disease and diabetes. Since brain possesses high energetic requirements, any decline in brain mitochondria electron chain could have a severe impact on brain function and particularly on the etiology of neurodegenerative diseases. This review is primarily focused in the discussion of brain mitochondrial dysfunction as a link between diabetes and Alzheimer's disease.
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Affiliation(s)
- Paula I Moreira
- Center for Neuroscience and Cell Biology, Institute of Physiology, Faculty of Medicine, University of Coimbra, 3004-354 Coimbra, Portugal
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32
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Kato M, Wynn RM, Chuang JL, Brautigam CA, Custorio M, Chuang DT. A synchronized substrate-gating mechanism revealed by cubic-core structure of the bovine branched-chain alpha-ketoacid dehydrogenase complex. EMBO J 2006; 25:5983-94. [PMID: 17124494 PMCID: PMC1698891 DOI: 10.1038/sj.emboj.7601444] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Accepted: 10/19/2006] [Indexed: 01/07/2023] Open
Abstract
The dihydrolipoamide acyltransferase (E2b) component of the branched-chain alpha-ketoacid dehydrogenase complex forms a cubic scaffold that catalyzes acyltransfer from S-acyldihydrolipoamide to CoA to produce acyl-CoA. We have determined the first crystal structures of a mammalian (bovine) E2b core domain with and without a bound CoA or acyl-CoA. These structures reveal both hydrophobic and the previously unreported ionic interactions between two-fold-related trimers that build up the cubic core. The entrance of the dihydrolipoamide-binding site in a 30-A long active-site channel is closed in the apo and acyl-CoA-bound structures. CoA binding to one entrance of the channel promotes a conformational change in the channel, resulting in the opening of the opposite dihydrolipoamide gate. Binding experiments show that the affinity of the E2b core for dihydrolipoamide is markedly increased in the presence of CoA. The result buttresses the model that CoA binding is responsible for the opening of the dihydrolipoamide gate. We suggest that this gating mechanism synchronizes the binding of the two substrates to the active-site channel, which serves as a feed-forward switch to coordinate the E2b-catalyzed acyltransfer reaction.
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Affiliation(s)
- Masato Kato
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - R Max Wynn
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jacinta L Chuang
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Chad A Brautigam
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Myra Custorio
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - David T Chuang
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA. Tel.: +1 214 648 2457; Fax: +1 214 648 8856; E-mail:
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Calabrese V, Sultana R, Scapagnini G, Guagliano E, Sapienza M, Bella R, Kanski J, Pennisi G, Mancuso C, Stella AMG, Butterfield DA. Nitrosative stress, cellular stress response, and thiol homeostasis in patients with Alzheimer's disease. Antioxid Redox Signal 2006; 8:1975-86. [PMID: 17034343 DOI: 10.1089/ars.2006.8.1975] [Citation(s) in RCA: 175] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder with cognitive and memory decline, personality changes, and synapse loss. Increasing evidence indicates that factors such as oxidative and nitrosative stress, glutathione depletion, and impaired protein metabolism can interact in a vicious cycle, which is central to AD pathogenesis. In the present study, we demonstrate that brains of AD patients undergo oxidative changes classically associated with a strong induction of the so-called vitagenes, including the heat shock proteins (HSPs) heme oxygenase-1 (HO-1), HSP60, and HSP72, as well as thioredoxin reductase (TRXr). In inferior parietal brain of AD patients, a significant increase in the expression of HO-1 and TRXr was observed, whereas HO-2 expression was decreased, compared with controls. TRHr was not increased in AD cerebellum. Plasma GSH was decreased in AD patients, compared with the control group, and was associated with a significant increase in oxidative stress markers (i.e., GSSG, hydroxynonenal, protein carbonyl content, and nitrotyrosine). In AD lymphocytes, we observed an increased expression of inducible nitric oxide synthase, HO-1, Hsp72, HSP60, and TRXr. Our data support a role for nitrative stress in the pathogenesis of AD and indicate that the stress-responsive genes, such as HO-1 and TRXr, may represent important targets for novel cytoprotective strategies.
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Affiliation(s)
- Vittorio Calabrese
- Department of Chemistry, Biochemistry, & Molecular Biology Section, Faculty of Medicine, University of Catania, Catania, Italy.
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Singh M, Dykens JA, Simpkins JW. Novel mechanisms for estrogen-induced neuroprotection. Exp Biol Med (Maywood) 2006; 231:514-21. [PMID: 16636299 DOI: 10.1177/153537020623100505] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Estrogens are gonadal steroid hormones that are present in the circulation of both males and females and that can no longer be considered within the strict confines of reproductive function. In fact, the bone, the cardiovascular system, and extrahypothalamic regions of the brain are now well-established targets of estrogens. Among the numerous aspects of brain function regulated by estrogens are their effects on mood, cognitive function, and neuronal viability. Here, we review the supporting evidence for estrogens as neuroprotective agents and summarize the various mechanisms that may be involved in this effect, focusing particularly on the mitochondria as an important target. On the basis of this evidence, we discuss the clinical applicability of estrogens in treating various age-related disorders, including Alzheimer disease and stroke, and identify the caveats that must be considered.
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Affiliation(s)
- Meharvan Singh
- Department of Pharmacology & Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
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35
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Moreira PI, Zhu X, Lee HG, Honda K, Smith MA, Perry G. The (un)balance between metabolic and oxidative abnormalities and cellular compensatory responses in Alzheimer disease. Mech Ageing Dev 2006; 127:501-6. [PMID: 16516950 DOI: 10.1016/j.mad.2006.01.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2006] [Indexed: 11/27/2022]
Abstract
Compelling evidence supports the importance of metabolic abnormalities in Alzheimer disease pathogenesis. Indeed, that oxidative mechanisms are involved in the neuropathology associated with Alzheimer disease is evidenced by the large number of metabolic signs of oxidative stress as well as by specific markers of oxidative damage. However, in the initial stages of disease development, neurons adapt to the oxidative environment through the development of compensatory responses resulting in a shift of neuronal priority from normal function to basic survival.
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Affiliation(s)
- Paula I Moreira
- Department of Pathology, Case Western Reserve University, 2103 Cornell Road, Cleveland, OH 44106, USA
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36
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Abstract
The integrity of mitochondrial function is fundamental to cell life. It follows that disturbances of mitochondrial function will lead to disruption of cell function, expressed as disease or even death. In this review, I consider recent developments in our knowledge of basic aspects of mitochondrial biology as an essential step in developing our understanding of the contributions of mitochondria to disease. The identification of novel mechanisms that govern mitochondrial biogenesis and replication, and the delicately poised signalling pathways that coordinate the mitochondrial and nuclear genomes are discussed. As fluorescence imaging has made the study of mitochondrial function within cells accessible, the application of that technology to the exploration of mitochondrial bioenergetics is reviewed. Mitochondrial calcium uptake plays a major role in influencing cell signalling and in the regulation of mitochondrial function, while excessive mitochondrial calcium accumulation has been extensively implicated in disease. Mitochondria are major producers of free radical species, possibly also of nitric oxide, and are also major targets of oxidative damage. Mechanisms of mitochondrial radical generation, targets of oxidative injury and the potential role of uncoupling proteins as regulators of radical generation are discussed. The role of mitochondria in apoptotic and necrotic cell death is seminal and is briefly reviewed. This background leads to a discussion of ways in which these processes combine to cause illness in the neurodegenerative diseases and in cardiac reperfusion injury. The demands of mitochondria and their complex integration into cell biology extends far beyond the provision of ATP, prompting a radical change in our perception of mitochondria and placing these organelles centre stage in many aspects of cell biology and medicine.
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Affiliation(s)
- Michael R Duchen
- Department of Physiology and Mitochondrial Biology Group, University College London, Gower Street, London WC1E 6BT, UK.
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Abramov AY, Canevari L, Duchen MR. Calcium signals induced by amyloid β peptide and their consequences in neurons and astrocytes in culture. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2004; 1742:81-7. [PMID: 15590058 DOI: 10.1016/j.bbamcr.2004.09.006] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2004] [Revised: 09/05/2004] [Accepted: 09/08/2004] [Indexed: 11/20/2022]
Abstract
In Alzheimer's disease, amyloid beta (Abeta) peptide is deposited in neuritic plaques in the brain. The Abeta peptide 1-42 or the fragment 25-35 are neurotoxic. We here review our recent explorations of the mechanisms of Abeta toxicity in hippocampal cultures. Abeta had no effect on intracellular calcium in neurons but caused striking changes in nearby astrocytes. The [Ca(2+)](c) signals started approximately 5-15 min after Abeta application and consisted of sporadic [Ca(2+)](c) pulses. These were entirely dependent on extracellular Ca(2+), independent of ER Ca(2+) stores and resulted from Ca(2+) influx, probably through Abeta-induced membrane channels. The Ca(2+) signals were closely associated with transient, episodic acidification which may reflect displacement of protons from binding sites or Ca(2+)/2H(+) exchange. Abeta caused an increased rate of generation of reactive oxygen species (ROS), also seen in astrocytes and not in neurons. The increased ROS generation was blocked by inhibitors of the NADPH oxidase, strongly suggesting that this enzyme, normally associated with immune cells, is expressed in astrocytes. ROS generation was also Ca(2+)-dependent, suggesting that Abeta activation of the enzyme may be secondary to the increase in [Ca(2+)](c). Abeta caused delayed neuronal death despite the fact that all responses were seen only in astrocytes. Neurons could not be protected by glutamate receptor antagonists, but were rescued by inhibition of the NADPH oxidase, by antioxidants and by increasing glutathione. These data suggest that Abeta causes Ca(2+)-dependent oxidative stress by activating an astrocytic NADPH oxidase, and that neuronal death follows through a failure of antioxidant support.
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Affiliation(s)
- Andrey Y Abramov
- Department of Physiology, University College London, Gower Street WC1E 6BT, London, UK
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38
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Abstract
Mitochondrial dysfunction and free radical-induced oxidative damage have been implicated in the pathogenesis of several different neurodegenerative diseases such as Parkinson disease (PD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD), and Alzheimer's disease (AD). The defective adenosine triphosphate (ATP) production and increased oxygen radicals may induce mitochondria-dependent cell death because damaged mitochondria are unable to maintain the energy demands of the cell. The role of vascular hypoperfusion-induced mitochondria failure in the pathogenesis of AD now has been widely accepted. However, the exact cellular mechanisms behind vascular lesions and their relation to oxidative stress markers identified by RNA oxidation, lipid peroxidation, or mitochondrial DNA (mtDNA) deletion remain unknown. Future studies comparing the spectrum of mitochondrial damage and the relationship to oxidative stress-induced damage during the aging process or, more importantly, during the maturation of AD pathology are warranted.
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Affiliation(s)
- Xiongwei Zhu
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio, USA
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Canevari L, Abramov AY, Duchen MR. Toxicity of amyloid beta peptide: tales of calcium, mitochondria, and oxidative stress. Neurochem Res 2004; 29:637-50. [PMID: 15038611 DOI: 10.1023/b:nere.0000014834.06405.af] [Citation(s) in RCA: 166] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Alzheimer's disease (AD) is characterized by the accumulation of amyloid-beta (Abeta) peptides. Although the disease undoubtedly reflects the interaction of complex multifactorial processes, Abeta itself is toxic to neurons in vitro and the load of Abeta in vivo correlates well with the degree of cognitive impairment. There has therefore been considerable interest in the mechanism(s) of Abeta neurotoxicity. We here review the basic biology of Abeta processing and consider some of the major areas of focus of this research. It is clear that both AD and Abeta toxicity are characterized by oxidative stress, alterations in the activity of enzymes of intermediary metabolism, and mitochondrial dysfunction, especially impaired activity of cytochrome c oxidase. Studies in vitro also show alterations in cellular calcium signaling. We consider the mechanisms proposed to mediate cell injury and explore evidence to indicate which of these many changes in function are primary and which secondary.
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Affiliation(s)
- Laura Canevari
- Division of Neurochemistry, Institute of Neurology, Queen Square, London WC1N 3BG, United Kingdom.
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40
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Abstract
Extensive, replicated evidence in patients in vivo and in Alzheimer (AD) tissues in vitro indicates that impaired brain metabolism is one of the cardinal and essentially invariable events in AD. The degree of impairment in brain metabolism is proportional to the degree of clinical disability, both in vivo and in vitro. The 'cerebrometabolic lesion' cannot be attributed to 'slower thinking' or 'brain atrophy', because of quantitative considerations and because the metabolic lesion precedes the development of neuropsychological abnormalities or decreases in brain mass detectable by modern imaging techniques. The causes of the cerebrometabolic lesion in AD are not well defined. Free radicals seem likely to be involved, including free radicals generated from Alzheimer amyloid. Thus, the importance of the cerebrometabolic lesion is entirely compatible with most versions of the widely accepted 'amyloid cascade hypothesis' of AD. A variety of plausible, redundantly documented mechanisms are compatible with the proposal that the cerebrometabolic lesion is a proximate cause of the clinical disability in AD. In agreement with these findings, recent attempts to treat the cerebrometabolic lesion in AD have given encouraging preliminary results. The cerebrometabolic lesion in AD deserves further study.
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Affiliation(s)
- John P Blass
- Dementia Research Service, Burke Medical Research Institute, Weill Medical College of Cornell University, 785 Mamaroneck Avenue, White Plains, NY 10708, USA.
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41
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Swerdlow RH, Kish SJ. Mitochondria in Alzheimer's disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2003; 53:341-85. [PMID: 12512346 DOI: 10.1016/s0074-7742(02)53013-0] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Russell H Swerdlow
- Department of Neurology, University of Virginia, Charlottesville, Virginia 22908, USA
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42
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Lucas DT, Aryal P, Szweda LI, Koch WJ, Leinwand LA. Alterations in mitochondrial function in a mouse model of hypertrophic cardiomyopathy. Am J Physiol Heart Circ Physiol 2003; 284:H575-83. [PMID: 12414446 DOI: 10.1152/ajpheart.00619.2002] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Familial hypertrophic cardiomyopathy (HCM) is an autosomal dominant disease characterized by varying degrees of ventricular hypertrophy and myofibrillar disarray. Mutations in cardiac contractile proteins cause HCM. However, there is an unexplained wide variability in the clinical phenotype, and it is likely that there are multiple contributing factors. Because mitochondrial dysfunction has been described in heart disease, we tested the hypothesis that mitochondrial dysfunction contributes to the varying HCM phenotypes. Mitochondrial function was assessed in two transgenic models of HCM: mice with a mutant myosin heavy chain gene (MyHC) or with a mutant cardiac troponin T (R92Q) gene. Despite mitochondrial ultrastructural abnormalities in both models, the rate of state 3 respiration was significantly decreased only in the mutant MyHC mice by approximately 23%. Notably, this decrease in state 3 respiration preceded hemodynamic dysfunction. The maximum activity of alpha-ketogutarate dehydrogenase as assayed in isolated disrupted mitochondria was decreased by 28% compared with isolated control mitochondria. In addition, complexes I and IV were decreased in mutant MyHC transgenic mice. Inhibition of beta-adrenergic receptor kinase, which is elevated in mutant MyHC mouse hearts, can prevent mitochondrial respiratory impairment in mutant MyHC mice. Thus our results suggest that mitochondria may contribute to the hemodynamic dysfunction seen in some forms of HCM and offer a plausible mechanism responsible for some of the heterogeneity of the disease phenotypes.
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Affiliation(s)
- David T Lucas
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder 80309, USA
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43
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Abstract
During normal cellular metabolism, mitochondrial electron transport results in the formation of superoxide anion (O(2)) and subsequently hydrogen peroxide (H(2)O(2)). Because H(2)O(2) increases in concentration under certain physiologic and pathophysiologic conditions and can oxidatively modify cellular components, it is critical to understand the response of mitochondria to H(2)O(2). In the present study, treatment of isolated rat heart mitochondria with H(2)O(2) resulted in a decline and subsequent recovery of state 3 NADH-linked respiration. Alterations in NADH levels induced by H(2)O(2) closely paralleled changes in the rate of state 3 respiration. Assessment of electron transport chain complexes and Krebs cycle enzymes revealed that alpha-ketoglutarate dehydrogenase (KGDH), succinate dehydrogenase (SDH), and aconitase were susceptible to H(2)O(2) inactivation. Of particular importance, KGDH and SDH activity returned to control levels, concurrent with the recovery of state 3 respiration. Inactivation is not because of direct interaction of H(2)O(2) with KGDH and SDH. In addition, removal of H(2)O(2) alone is not sufficient for reactivation. Enzyme activity does not recover unless mitochondria remain intact. The sensitivity of KGDH and SDH to H(2)O(2)-mediated inactivation and the reversible nature of inactivation suggest a potential role for H(2)O(2) in the regulation of KGDH and SDH.
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Affiliation(s)
- A C Nulton-Persson
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio 44106-4970, USA
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de la Torre JC. Impaired cerebromicrovascular perfusion. Summary of evidence in support of its causality in Alzheimer's disease. Ann N Y Acad Sci 2001; 924:136-52. [PMID: 11193790 DOI: 10.1111/j.1749-6632.2000.tb05572.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
After nearly a century of inquiry, the cause of Alzheimer's disease (AD) remains to be found. In this review, basic and clinical evidence is presented that assembles and hypothetically explains most of the key pathologic events associated with the development of AD. These pathologic events are triggered in AD by impaired cerebral perfusion originating in the microvasculature that affects the optimal delivery of glucose and oxygen and results in an energy metabolic breakdown of brain cell biosynthetic and synaptic pathways. We propose that two factors must be present before cognitive dysfunction and neurodegeneration is expressed in the AD brain: (1) advanced aging, (2) presence of a condition that lowers cerebral perfusion, such as a vascular risk factor. The first factor introduces a normal but potentially menacing process that lowers cerebral blood flow in proportion to increased aging, while the second factor adds a crucial burden that further lowers brain perfusion and places vulnerable neurons in a state of metabolic compromise leading to a death pathway. These two factors will lead to a critically attained threshold of cerebral hypoperfusion (CATCH). CATCH is a self-sustaining and progressive circulatory insufficiency that will destabilize neurons, synapses, neurotransmission, and cognitive function, creating in its wake a neurodegenerative process characterized by the formation of senile plaques, neurofibrillary tangles, amyloid angiopathy, and, in some cases, Lewy bodies. Since any of a considerable number of vessel-related conditions must be present in the aging individual for cognition to be affected, CATCH supports the heterogeneic disease profile assumed to be characteristic of the AD syndrome. A brief discussion of target therapy based on the proposed pathogenesis of AD is also reviewed.
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Affiliation(s)
- J C de la Torre
- Department of Neuroscience, University of California, San Diego, La Jolla, California 92093, USA.
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45
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Buerstatte CR, Behar KL, Novotny EJ, Lai JC. Brain regional development of the activity of alpha-ketoglutarate dehydrogenase complex in the rat. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2000; 125:139-45. [PMID: 11154769 DOI: 10.1016/s0165-3806(00)00134-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study was initiated to test the hypothesis that the development of alpha-ketoglutarate dehydrogenase complex (KGDHC) activity, like that of pyruvate dehydrogenase complex, is one of the late developers of tricarboxylic acid (TCA) cycle enzymes. The postnatal development of KGDHC in rat brain exhibits four distinct region-specific patterns. The age-dependent increases in olfactory bulb (OB) and hypothalamus (HYP) form one pattern: low in postnatal days (P) 2 and 4, KGDHC activity rose linearly to attain adult level at P30. The increases in mid-brain (MB) and striatum (ST) constitute a second pattern: being <40% of adult level at P2 and P4, KGDHC activity rose steeply between P10 and P17 and attained adult level by P30. The increases in cerebellum (CB), cerebral cortex (CC), and hippocampus (HIP) form a third pattern: being 25-30% of adult level at P2 and P4, KGDHC activity doubled between P10 and P17 and rose to adult level by P30. KGDHC activity development is unique in pons and medulla (PM): being >60% of the adult level at P2, it rose rapidly to adult level by P10. Thus, KGDHC activity develops earlier in phylogenetically older regions (PM) than in phylogenetically younger regions (CB, CC, HIP). Being lowest in activity among all TCA cycle enzymes, KGDHC activity in any region at any age will exert a limit on the maximum TCA cycle flux therein. The results may have functional and pathophysiological implications in control of brain glucose oxidative metabolism, energy metabolism, and neurotransmitter syntheses.
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Affiliation(s)
- C R Buerstatte
- Department of Pharmaceutical Sciences, College of Pharmacy, Idaho State University, Campus Box 8334, Pocatello, ID 83209-8334, USA
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46
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de la Torre JC, Stefano GB. Evidence that Alzheimer's disease is a microvascular disorder: the role of constitutive nitric oxide. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 2000; 34:119-36. [PMID: 11113503 DOI: 10.1016/s0165-0173(00)00043-6] [Citation(s) in RCA: 208] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Evidence is fast accumulating which indicates that Alzheimer's disease is a vascular disorder with neurodegenerative consequences rather than a neurodegenerative disorder with vascular consequences. It is proposed that two factors need to be present for AD to develop: (1) advanced ageing, (2) presence of a condition that lowers cerebral perfusion, such as a vascular-risk factor. The first factor introduces a normal but potentially insidious process that lowers cerebral blood flow in inverse relation to increased ageing; the second factor adds a crucial burden which further lowers brain perfusion and places vulnerable neurons in a state of high energy compromise leading to a cascade of neuronal metabolic turmoil. Convergence of the two factors above will culminate in a critically attained threshold of cerebral hypoperfusion (CATCH). CATCH is a hemodynamic microcirculatory insufficiency that will destabilize neurons, synapses, neurotransmission and cognitive function, creating in its wake a neurodegenerative state characterized by the formation of senile plaques, neurofibrillary tangles, amyloid angiopathy and in some cases, Lewy bodies. Since any of a considerable number of vascular-related conditions must be present in the ageing individual for cognition to be disturbed, CATCH identifies an important aspect of the heterogeneic disease profile assumed to be present in the AD syndrome. It is proposed that CATCH initiates AD by distorting regional brain capillary structure involving endothelial cell shape changes and impairment of nitric oxide (NO) release which affect signaling between the immune, cardiovascular and nervous systems. Evidence is presented that in many tissues there is a basal level of NO being produced and that the actions of several signaling molecules may initiate increases in basal NO levels. Moreover, these temporary increases in basal NO levels exert inhibitory cellular actions, via cellular conformational changes. Findings indicate that (a) constitutive NO is responsible for a basal or 'tonal' level of NO; (b) this NO keeps particular types of cells in a state of inhibition and (c) activation of these cells occurs through disinhibition. Consequently, tissues not maintaining a basal NO level are more prone to excitatory, immune, vascular and neural influences. Under such circumstances, these tissues cannot be down-regulated to normal basal levels, thus prolonging their excitatory state. Thus, the clinical convergence of advanced ageing in the presence of a chronic, pre-morbid vascular risk factor, can, in time, contribute to an endotheliopathy involving basal NO deficit, to the degree where regional metabolic dysfunction leads to cognitive meltdown and to progressive neurodegeneration characteristic of Alzheimer's disease.
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Affiliation(s)
- J C de la Torre
- Department of Pathology, University of California, San Diego, 1363 Shinly, Suite 100, Escondido, CA 92026, USA.
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47
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Abstract
Brain aging, Alzheimer disease and stroke share common elements of deficits in calcium regulation, declines in mitochondrial function, increases in generation of reactive oxygen species (ROS), accumulated damage from ROS and immune system dysfunction. The problem is to distinguish less significant side reactions, such as gray hair, from aspects of aging that contribute to disease. Toward establishing cause and effect relationships, a neuron cell culture system is described that allows comparisons with age under uniform environmental conditions. This neuron culture model indicates that susceptibility to death by apoptosis and consequences of the inflammatory response from beta-amyloid are age-related and an inherent characteristic of the neurons. Further mechanistic investigations are possible. New therapeutic approaches are suggested that combine inhibition of calcium overloads (calcium channel blockers), reduced ROS damage (melatonin, N-acetyl-cysteine), and bolstered mitochondrial function and energy generation (creatine). Together with newly demonstrated capabilities for adult and aged neuron regeneration and multiplication, i.e. plasticity, these approaches offer new hope toward reversing age-related decrements and damage from neurodegenerative disease.
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Affiliation(s)
- G J Brewer
- Department of Neurology, School of Medicine, Southern Illinois University, Springfield, IL, 62794-9626, USA.
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Pettegrew JW, Levine J, McClure RJ. Acetyl-L-carnitine physical-chemical, metabolic, and therapeutic properties: relevance for its mode of action in Alzheimer's disease and geriatric depression. Mol Psychiatry 2000; 5:616-32. [PMID: 11126392 DOI: 10.1038/sj.mp.4000805] [Citation(s) in RCA: 199] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Acetyl-L-carnitine (ALCAR) contains carnitine and acetyl moieties, both of which have neurobiological properties. Carnitine is important in the beta-oxidation of fatty acids and the acetyl moiety can be used to maintain acetyl-CoA levels. Other reported neurobiological effects of ALCAR include modulation of: (1) brain energy and phospholipid metabolism; (2) cellular macromolecules, including neurotrophic factors and neurohormones; (3) synaptic morphology; and (4) synaptic transmission of multiple neurotransmitters. Potential molecular mechanisms of ALCAR activity include: (1) acetylation of -NH2 and -OH functional groups in amino acids and N terminal amino acids in peptides and proteins resulting in modification of their structure, dynamics, function and turnover; and (2) acting as a molecular chaperone to larger molecules resulting in a change in the structure, molecular dynamics, and function of the larger molecule. ALCAR is reported in double-blind controlled studies to have beneficial effects in major depressive disorders and Alzheimer's disease (AD), both of which are highly prevalent in the geriatric population.
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Affiliation(s)
- J W Pettegrew
- Department of Psychiatry, School of Medicine, University of Pittsburgh, PA 15213, USA. pettegre+@pitt.edu
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Gibson GE, Park LC, Zhang H, Sorbi S, Calingasan NY. Oxidative stress and a key metabolic enzyme in Alzheimer brains, cultured cells, and an animal model of chronic oxidative deficits. Ann N Y Acad Sci 2000; 893:79-94. [PMID: 10672231 DOI: 10.1111/j.1749-6632.1999.tb07819.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Oxidative stress and diminished metabolism occur in several neurodegenerative disorders. Brains from Alzheimer's disease (AD) patients exhibit several indicators of oxidative stress and have reduced activities of the alpha-ketoglutarate dehydrogenase complex (KGDHC), a key mitochondrial enzyme. Whether these abnormalities are secondary to neurodegenerative processes or are inherent properties of the cells cannot be determined in autopsy brain. Studies in cultured fibroblasts suggest that AD-related differences in oxidative stress and KGDHC reflect inherent properties of AD cells. KGDHC is sensitive to oxidative stress whether the enzyme is studied in cells, in purified mitochondria, or as an isolated protein. Reductions of brain KGDHC in living rodents lead to oxidative stress and selective cell death. The results suggest that KGDHC participates in a deleterious cascade of events related to oxidative stress that are critical in selective neuronal loss in neurodegenerative diseases.
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Affiliation(s)
- G E Gibson
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University at Burke Medical Research Institute, White Plains, New York 10605, USA.
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Aksenov MY, Tucker HM, Nair P, Aksenova MV, Butterfield DA, Estus S, Markesbery WR. The expression of several mitochondrial and nuclear genes encoding the subunits of electron transport chain enzyme complexes, cytochrome c oxidase, and NADH dehydrogenase, in different brain regions in Alzheimer's disease. Neurochem Res 1999; 24:767-74. [PMID: 10447460 DOI: 10.1023/a:1020783614031] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In this study, changes of the expression of two mitochondrial and two nuclear genes encoding the subunits of cytochrome c oxidase (CO) and NADH dehydrogenase (ND) were studied in the hippocampus, inferior parietal lobule, and cerebellum of 10 Alzheimer's disease (AD) and 10 age-matched control subjects. The altered proportion between CO II and CO IV mRNAs was observed in the AD brain. Changes of the proportion between CO II and CO IV transcripts may contribute to the kinetic perturbation of CO documented in AD. A coordinated decrease of ND4 and ND15 mRNAs was found in the AD hippocampus and inferior parietal lobule, but not in cerebellum. The decrease of ND4 gene expression may lead to the inhibition of normal ubiquinone oxidoreductase activity of ND. This study suggests that changes of the expression of mitochondrial and nuclear genes, encoding parts of ND and CO enzyme complexes, may contribute to alterations of oxidative metabolism in AD.
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Affiliation(s)
- M Y Aksenov
- Sanders-Brown Center on Aging, University of Kentucky, Lexington 40536, USA. mikeal@.uky.campus.mci.net
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