Nejvíce citovaný článek - PubMed ID 19734902
Neural networks are responsible for processing sensory stimuli and driving the synaptic activity required for brain function and behavior. This computational capacity is expensive and requires a steady supply of energy and building blocks to operate. Importantly, the neural networks are composed of different cell populations, whose metabolic profiles differ between each other, thus endowing them with different metabolic capacities, such as, for example, the ability to synthesize specific metabolic precursors or variable proficiency to manage their metabolic waste. These marked differences likely prompted the emergence of diverse intercellular metabolic interactions, in which the shuttling and cycling of specific metabolites between brain cells allows the separation of workload and efficient control of energy demand and supply within the central nervous system. Nevertheless, our knowledge about brain bioenergetics and the specific metabolic adaptations of neural cells still warrants further studies. In this review, originated from the Fourth International Society for Neurochemistry (ISN) and Journal of Neurochemistry (JNC) Flagship School held in Schmerlenbach, Germany (2022), we describe and discuss the specific metabolic profiles of brain cells, the intercellular metabolic exchanges between these cells, and how these bioenergetic activities shape synaptic function and behavior. Furthermore, we discuss the potential role of faulty brain metabolic activity in the etiology and progression of Alzheimer's disease, Parkinson disease, and Amyotrophic lateral sclerosis. We foresee that a deeper understanding of neural networks metabolism will provide crucial insights into how higher-order brain functions emerge and reveal the roots of neuropathological conditions whose hallmarks include impaired brain metabolic function.
- Klíčová slova
- astrocytes, glycolysis, lipids, mitochondria, neurodegeneration, neurons,
- MeSH
- energetický metabolismus * fyziologie MeSH
- lidé MeSH
- metabolické sítě a dráhy * fyziologie MeSH
- mozek * metabolismus MeSH
- nervová síť * metabolismus MeSH
- neurony * metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Aging and age-related neurodegenerative disorders are characterized by the dysfunction or loss of brain nicotinic acetylcholine receptors (nAChRs), and these changes may be related to other senescence markers, such as oxidative stress and DNA repair dysfunction. However, the mechanism of nAChR loss in the aging brain and the modification of this process by drugs (e.g., memantine, Mem) are not yet fully understood. To study whether the differences in nAChR expression in the rat brain occur due to aging or oxidative stress and are modulated by Mem, we analyzed nAChR subunits (at RNA and protein levels) and other biomarkers by real-time quantitative polymerase chain reaction (RQ-PCR) and Western blot validation. Twenty-one female Wistar rats were divided into four groups, depending on age, and the oldest group received injections of Mem or water with the use of intragastric catheters. We studied the cerebral grey matter (CGM), subcortical white matter (SCWM), and cerebellum (Ce). Results showed an age-related decrease of α7 nAChR mRNA level in SCWM. The α7 nAChR mRNA loss was accompanied by reduced expression of 8-oxoguanine DNA glycosylase 1 (OGG1) and an increased tumor necrosis factor alpha (TNFα) level. In the water group, we observed a higher level of α7 nAChR protein in the SCWM and Ce. Biomarker levels changed, but to a different extent depending on the brain area. Importantly, the dysfunction in antioxidative status was stopped and even regressed under Mem treatment. After two weeks of treatment, an increase in TP53 protein level and a decrease in 8-oxo-2'deoxyguanosine (8-oxo-2'dG) level were observed. We conclude that Mem administration may be protective against the senescence process by antioxidative mechanisms.
- Klíčová slova
- aging, brain, memantine, nicotinic receptor, oxidative stress,
- MeSH
- alfa7 nikotinové acetylcholinové receptory * genetika metabolismus MeSH
- DNA-glykosylasy metabolismus genetika MeSH
- krysa rodu Rattus MeSH
- memantin * farmakologie MeSH
- mozek * metabolismus účinky léků MeSH
- nikotinové receptory * metabolismus genetika MeSH
- oxidační stres * účinky léků MeSH
- poškození DNA * účinky léků MeSH
- potkani Wistar MeSH
- stárnutí * metabolismus genetika účinky léků MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- alfa7 nikotinové acetylcholinové receptory * MeSH
- DNA-glykosylasy MeSH
- memantin * MeSH
- nikotinové receptory * MeSH
Alzheimer's disease (AD) is one of the most persistent and devastating neurodegenerative disorders of old age, and is characterized clinically by an insidious onset and a gradual, progressive deterioration of cognitive abilities, ranging from loss of memory to impairment of judgement and reasoning. Despite years of research, an effective cure is still not available. Autophagy is the cellular 'garbage' clearance system which plays fundamental roles in neurogenesis, neuronal development and activity, and brain health, including memory and learning. A selective sub-type of autophagy is mitophagy which recognizes and degrades damaged or superfluous mitochondria to maintain a healthy and necessary cellular mitochondrial pool. However, emerging evidence from animal models and human samples suggests an age-dependent reduction of autophagy and mitophagy, which are also compromised in AD. Upregulation of autophagy/mitophagy slows down memory loss and ameliorates clinical features in animal models of AD. In this review, we give an overview of autophagy and mitophagy and their link to the progression of AD. We also summarize approaches to upregulate autophagy/mitophagy. We hypothesize that age-dependent compromised autophagy/mitophagy is a cause of brain ageing and a risk factor for AD, while restoration of autophagy/mitophagy to more youthful levels could return the brain to health.
- Klíčová slova
- Ageing, Alzheimer’s disease, Autophagy, Mitophagy,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Damage or loss of brain cells and impaired neurochemistry, neurogenesis, and synaptic and nonsynaptic plasticity of the brain lead to dementia in neurodegenerative diseases, such as Alzheimer's disease (AD). Injury to synapses and neurons and accumulation of extracellular amyloid plaques and intracellular neurofibrillary tangles are considered the main morphological and neuropathological features of AD. Age, genetic and epigenetic factors, environmental stressors, and lifestyle contribute to the risk of AD onset and progression. These risk factors are associated with structural and functional changes in the brain, leading to cognitive decline. Biomarkers of AD reflect or cause specific changes in brain function, especially changes in pathways associated with neurotransmission, neuroinflammation, bioenergetics, apoptosis, and oxidative and nitrosative stress. Even in the initial stages, AD is associated with Aβ neurotoxicity, mitochondrial dysfunction, and tau neurotoxicity. The integrative amyloid-tau-mitochondrial hypothesis assumes that the primary cause of AD is the neurotoxicity of Aβ oligomers and tau oligomers, mitochondrial dysfunction, and their mutual synergy. For the development of new efficient AD drugs, targeting the elimination of neurotoxicity, mutual potentiation of effects, and unwanted protein interactions of risk factors and biomarkers (mainly Aβ oligomers, tau oligomers, and mitochondrial dysfunction) in the early stage of the disease seems promising.
- Klíčová slova
- Alzheimer’s disease, amyloid beta, drug, mitochondria, tau protein,
- MeSH
- Alzheimerova nemoc * metabolismus MeSH
- amyloid metabolismus MeSH
- amyloidní beta-protein metabolismus MeSH
- amyloidogenní proteiny metabolismus MeSH
- lidé MeSH
- mitochondrie metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- amyloid MeSH
- amyloidní beta-protein MeSH
- amyloidogenní proteiny MeSH
Clusterin (CLU; also known as apolipoprotein J, ApoJ) is a protein of inconstant structure known to be involved in diverse processes inside and outside of brain cells. CLU can act as a protein chaperon or protein solubilizer, lipid transporter as well as redox sensor and be anti- or proapoptotic, depending on context. Primary structure of CLU is encoded by CLU gene which contains single nucleotide polymorphisms (SNP's) associated with the risk of late-onset Alzheimer's disease (LOAD). Studying a sample of Czech population and using the case-control association approach we identified C allele of the SNP rs11136000 as conferring a reduced risk of LOAD, more so in females than in males. Additionally, data from two smaller subsets of the population sample suggested a possible association of rs11136000 with diabetes mellitus. In a parallel study, we found no association between rs11136000 and mild cognitive impairment (MCI). Our findings on rs11136000 and LOAD contradict those of some previous studies done elsewhere. We discuss the multiple roles of CLU in a broad range of molecular mechanisms that may contribute to the variability of genetic studies of CLU in various ethnic groups. The above discordance notwithstanding, our conclusions support the association of rs1113600 with the risk of LOAD.
- Klíčová slova
- Clusterin, Genetic risk, Late-onset Alzheimer’s disease, Mild cognitive impairment, Neurodegeneration, Neuroprotection, Single nucleotide polymorphism,
- MeSH
- Alzheimerova nemoc etiologie genetika MeSH
- genetická predispozice k nemoci MeSH
- jednonukleotidový polymorfismus MeSH
- klusterin genetika MeSH
- kognitivní dysfunkce etiologie genetika MeSH
- lidé MeSH
- rizikové faktory MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- CLU protein, human MeSH Prohlížeč
- klusterin MeSH
Premature termination codon (PTC) mutations in the ATP-Binding Cassette, Sub-Family A, Member 7 gene (ABCA7) have recently been identified as intermediate-to-high penetrant risk factor for late-onset Alzheimer's disease (LOAD). High variability, however, is observed in downstream ABCA7 mRNA and protein expression, disease penetrance, and onset age, indicative of unknown modifying factors. Here, we investigated the prevalence and disease penetrance of ABCA7 PTC mutations in a large early onset AD (EOAD)-control cohort, and examined the effect on transcript level with comprehensive third-generation long-read sequencing. We characterized the ABCA7 coding sequence with next-generation sequencing in 928 EOAD patients and 980 matched control individuals. With MetaSKAT rare variant association analysis, we observed a fivefold enrichment (p = 0.0004) of PTC mutations in EOAD patients (3%) versus controls (0.6%). Ten novel PTC mutations were only observed in patients, and PTC mutation carriers in general had an increased familial AD load. In addition, we observed nominal risk reducing trends for three common coding variants. Seven PTC mutations were further analyzed using targeted long-read cDNA sequencing on an Oxford Nanopore MinION platform. PTC-containing transcripts for each investigated PTC mutation were observed at varying proportion (5-41% of the total read count), implying incomplete nonsense-mediated mRNA decay (NMD). Furthermore, we distinguished and phased several previously unknown alternative splicing events (up to 30% of transcripts). In conjunction with PTC mutations, several of these novel ABCA7 isoforms have the potential to rescue deleterious PTC effects. In conclusion, ABCA7 PTC mutations play a substantial role in EOAD, warranting genetic screening of ABCA7 in genetically unexplained patients. Long-read cDNA sequencing revealed both varying degrees of NMD and transcript-modifying events, which may influence ABCA7 dosage, disease severity, and may create opportunities for therapeutic interventions in AD.
- Klíčová slova
- ATP-Binding Cassette, Early Onset Alzheimer’s disease, Loss-of-function, Member 7 (ABCA7), Modifier, RNA sequencing, Sub-Family A, Third-generation long-read sequencing,
- MeSH
- ABC transportéry genetika MeSH
- Alzheimerova nemoc genetika MeSH
- dospělí MeSH
- genetická predispozice k nemoci * MeSH
- genetické asociační studie MeSH
- jednonukleotidový polymorfismus * MeSH
- lidé středního věku MeSH
- lidé MeSH
- mutace * MeSH
- senioři MeSH
- věk při počátku nemoci MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- ABC transportéry MeSH
- ABCA7 protein, human MeSH Prohlížeč
Alzheimer's disease (AD) is the most common type of dementia, with a prevalence that is rising every year. AD is associated with type 2 diabetes mellitus (T2DM) and insulin resistance, and is therefore sometimes called "type 3 diabetes mellitus". The aim of this study was to examine whether the variants of some candidate genes involved in the development of AD, namely BIN1 (rs744373), CLU (rs11136000), CR1 (rs3818361), and PICALM (rs3851179), are related to several disorders of glucose metabolism-gestational diabetes (GDM), T2DM and impaired glucose tolerance (IGT). Our study included 550 women with former GDM and 717 control women, 392 patients with T2DM and 180 non-diabetic controls, and 117 patients with IGT and 630 controls with normal glucose tolerance. Genotyping analysis was performed using specially-designed TaqMan assays. No significant associations of the genetic variants rs744373 in BIN1, rs11136000 in CLU, or rs3818361 in CR1 were found with GDM, T2DM or IGT, but rs3851179 in PICALM was associated with an increased risk of GDM. The frequency of the AD risk-associated C allele was significantly higher in the GDM group compared to controls: OR 1.21; 95% CI (1.03-1.44). This finding was not apparent in T2DM and IGT; conversely, the C allele of the PICALM SNP was protective for IGT: OR 0.67; 95% CI (0.51-0.89). This study demonstrates an association between PICALM rs3851179 and GDM as well as IGT. However, elucidation of the possible role of this gene in the pathogenesis of GDM requires further independent studies.
- Klíčová slova
- Alzheimer’s disease, Gestational diabetes mellitus, Glucose metabolism, Impaired glucose tolerance, Polymorphisms, Type 2 diabetes mellitus,
- MeSH
- adaptorové proteiny signální transdukční krev genetika MeSH
- alely MeSH
- Alzheimerova nemoc komplikace genetika MeSH
- běloši genetika MeSH
- diabetes mellitus 2. typu genetika MeSH
- dospělí MeSH
- frekvence genu MeSH
- genetická predispozice k nemoci MeSH
- genetická variace MeSH
- genetické asociační studie metody MeSH
- gestační diabetes genetika metabolismus MeSH
- jaderné proteiny krev genetika MeSH
- jednonukleotidový polymorfismus genetika MeSH
- klusterin krev genetika MeSH
- lidé středního věku MeSH
- lidé MeSH
- monomerní proteiny vytvářející klathrin krev genetika MeSH
- nádorové supresorové proteiny krev genetika MeSH
- odds ratio MeSH
- porucha glukózové tolerance genetika metabolismus MeSH
- receptory komplementu 3b krev genetika MeSH
- rizikové faktory MeSH
- senioři MeSH
- těhotenství MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- adaptorové proteiny signální transdukční MeSH
- BIN1 protein, human MeSH Prohlížeč
- CLU protein, human MeSH Prohlížeč
- CR1 protein, human MeSH Prohlížeč
- jaderné proteiny MeSH
- klusterin MeSH
- monomerní proteiny vytvářející klathrin MeSH
- nádorové supresorové proteiny MeSH
- PICALM protein, human MeSH Prohlížeč
- receptory komplementu 3b MeSH
Alzheimer's disease (AD) is the most common form of dementia. The risk of AD increases with age. Although two of the main pathological features of AD, amyloid plaques and neurofibrillary tangles, were already recognized by Alois Alzheimer at the beginning of the 20th century, the pathogenesis of the disease remains unsettled. Therapeutic approaches targeting plaques or tangles have not yet resulted in satisfactory improvements in AD treatment. This may, in part, be due to early-onset and late-onset AD pathogenesis being underpinned by different mechanisms. Most animal models of AD are generated from gene mutations involved in early onset familial AD, accounting for only 1% of all cases, which may consequently complicate our understanding of AD mechanisms. In this article, the authors discuss the pathogenesis of AD according to the two main neuropathologies, including senescence-related mechanisms and possible treatments using stem cells, namely mesenchymal and neural stem cells.
- Klíčová slova
- Alzheimer’s disease, Tau, amyloid-β, mesenchymal stem cells, neural stem cells,
- MeSH
- Alzheimerova nemoc etiologie metabolismus patologie terapie MeSH
- amyloidní beta-protein imunologie metabolismus MeSH
- amyloidní plaky metabolismus patologie MeSH
- buněčná a tkáňová terapie * metody MeSH
- energetický metabolismus MeSH
- imunoterapie metody MeSH
- kmenové buňky cytologie metabolismus MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- mutace MeSH
- neuroglie metabolismus MeSH
- proteiny tau imunologie metabolismus MeSH
- stárnutí genetika imunologie metabolismus MeSH
- transplantace kmenových buněk metody MeSH
- věk při počátku nemoci MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- amyloidní beta-protein MeSH
- proteiny tau MeSH