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European Archives of Psychiatry and... Aug 2021The objective is to understand genetic predisposition to delirium. Following PRISMA guidelines, we undertook a systematic review of studies involving delirium and... (Meta-Analysis)
Meta-Analysis
The objective is to understand genetic predisposition to delirium. Following PRISMA guidelines, we undertook a systematic review of studies involving delirium and genetics in the databases of Pubmed, Scopus, Cochrane Library and PsycINFO, and performed a meta-analysis when appropriate. We evaluated 111 articles, of which 25 were finally included in the analysis. The studies were assessed by two independent researchers for methodological quality using the Downs and Black Tool and for genetic analysis quality. We performed a meta-analysis of 10 studies of the Apolipoprotein E (APOE) gene, obtaining no association with the presence of delirium (LOR 0.18, 95% CI - 0.10-0.47, p = 0.21). Notably, only 5 out of 25 articles met established criteria for genetic studies (good quality) and 6 were of moderate quality. Seven studies found an association with APOE4, the dopamine transporter gene SCL6A3, dopamine receptor 2 gene, glucocorticoid receptor, melatonin receptor and mitochondrial DNA haplotypes. One genome-wide association study found two suggestive long intergenic non-coding RNA genes. Five studies found no association with catechol-o-methyltransferase, melatonin receptor or several interleukins genes. The studies were heterogenous in establishing the presence of delirium. Future studies with large samples should further specify the delirium phenotype and deepen our understanding of interactions between genes and other biological factors.
Topics: Delirium; Genetic Predisposition to Disease; Humans
PubMed: 33779822
DOI: 10.1007/s00406-021-01255-x -
Neurobiology of Disease Feb 2021Neurodegenerative disorders such as Alzheimer's disease (AD), Lewy body diseases (LBD), and the amyotrophic lateral sclerosis and frontotemporal dementia (ALS-FTD)... (Meta-Analysis)
Meta-Analysis
Neurodegenerative disorders such as Alzheimer's disease (AD), Lewy body diseases (LBD), and the amyotrophic lateral sclerosis and frontotemporal dementia (ALS-FTD) spectrum are defined by the accumulation of specific misfolded protein aggregates. However, the mechanisms by which each proteinopathy leads to neurodegeneration remain elusive. We hypothesized that there is a common "pan-neurodegenerative" gene expression signature driving pathophysiology across these clinically and pathologically diverse proteinopathies. To test this hypothesis, we performed a systematic review of human CNS transcriptomics datasets from AD, LBD, and ALS-FTD patients and age-matched controls in the Gene Expression Omnibus (GEO) and ArrayExpress databases, followed by consistent processing of each dataset, meta-analysis, pathway enrichment, and overlap analyses. After applying pre-specified eligibility criteria and stringent data pre-processing, a total of 2600 samples from 26 AD, 21 LBD, and 13 ALS-FTD datasets were included in the meta-analysis. The pan-neurodegenerative gene signature is characterized by an upregulation of innate immunity, cytoskeleton, and transcription and RNA processing genes, and a downregulation of the mitochondrial electron transport chain. Pathway enrichment analyses also revealed the upregulation of neuroinflammation (including Toll-like receptor, TNF, and NFκB signaling) and phagocytosis, and the downregulation of mitochondrial oxidative phosphorylation, lysosomal acidification, and ubiquitin-proteasome pathways. Our findings suggest that neuroinflammation and a failure in both neuronal energy metabolism and protein degradation systems are consistent features underlying neurodegenerative diseases, despite differences in the extent of neuronal loss and brain regions involved.
Topics: Alzheimer Disease; Amyotrophic Lateral Sclerosis; Brain; Energy Metabolism; Frontotemporal Dementia; Humans; Inflammation; Inflammation Mediators; Lewy Body Disease; Neurodegenerative Diseases; Proteostasis; Transcriptome
PubMed: 33347974
DOI: 10.1016/j.nbd.2020.105225 -
Cellular and Molecular Neurobiology May 2022Neurodegenerative diseases might be slow but relentless, as we continue to fail in treating or delaying their progression. Given the complexity in the pathogenesis of... (Review)
Review
Neurodegenerative diseases might be slow but relentless, as we continue to fail in treating or delaying their progression. Given the complexity in the pathogenesis of these diseases, a broad-acting approach like photobiomodulation can prove promising. Photobiomodulation (PBM) uses red and infrared light for therapeutic benefits, working by stimulating growth and proliferation. The implications of photobiomodulation have been studied in several neurodegenerative disease models. It has been shown to improve cell survival, decrease apoptosis, alleviate oxidative stress, suppress inflammation, and rescue mitochondrial function. In in vivo models, it has reportedly preserved motor and cognitive skills. Beyond mitochondrial stimulation, the molecular mechanisms by which photobiomodulation protects against neurodegeneration have not been very well studied. This review has systematically been undertaken to study the effects of photobiomodulation at a molecular level and identify the different biochemical pathways and molecular changes in the process. The data showed the involvement of pathways like extracellular signal-regulated kinase (ERK), mitogen-activated protein kinase (MAPK), and protein kinase B (Akt). In addition, the expression of several genes and proteins playing different roles in the disease mechanisms was found to be influenced by PBM, such as neurotrophic factors and secretases. Studying the literature indicated that PBM can be translated to a potential therapeutic tool, acting through a spectrum of mechanisms that work together to decelerate disease progression in the organism, which is difficult to achieve through pharmacological interventions.
Topics: Cell Survival; Humans; Low-Level Light Therapy; Mitochondria; Mitogen-Activated Protein Kinases; Neurodegenerative Diseases
PubMed: 33301129
DOI: 10.1007/s10571-020-01016-9 -
Molecular Biology Reports Dec 2020The mitochondrial encephalomyopathies represent a clinically heterogeneous group of neurodegenerative disorders. The clinical phenotype of patients could be explained by... (Review)
Review
The mitochondrial encephalomyopathies represent a clinically heterogeneous group of neurodegenerative disorders. The clinical phenotype of patients could be explained by mutations of mitochondria-related genes, notably SUCLG1 and SUCLA2. Here, we presented a 5-year-old boy with clinical features of mitochondrial encephalomyopathy from Iran. Also, a systematic review was performed to explore the involvement of SUCLG1 mutations in published mitochondrial encephalomyopathies cases. Genotyping was performed by implementing whole-exome sequencing. Moreover, quantification of the mtDNA content was performed by real-time qPCR. We identified a novel, homozygote missense variant chr2: 84676796 A > T (hg19) in the SUCLG1 gene. This mutation substitutes Cys with Ser at the 60-position of the SUCLG1 protein. Furthermore, the in-silico analysis revealed that the mutated position in the genome is well conserved in mammalians, that implies mutation in this residue would possibly result in phenotypic consequences. Here, we identified a novel, homozygote missense variant chr2: 84676796 A > T in the SUCLG1 gene. Using a range of experimental and in silico analysis, we found that the mutation might explain the observed phenotype in the family.
Topics: Child, Preschool; DNA, Mitochondrial; Homozygote; Humans; Iran; Male; Mitochondria; Mitochondrial Encephalomyopathies; Mutation, Missense; Succinate-CoA Ligases
PubMed: 33230783
DOI: 10.1007/s11033-020-05999-y -
Environmental Research Feb 2021Exposure to air pollution during the first 1000 days of life (from conception to the 2nd year of life) might be of particular relevance for long-term child health.... (Review)
Review
BACKGROUND
Exposure to air pollution during the first 1000 days of life (from conception to the 2nd year of life) might be of particular relevance for long-term child health. Changes in molecular markers such as DNA methylation and telomere length could underlie the association between air pollution exposure and pollution-related diseases as well as serve as biomarkers for past exposure. The objective of this systematic review was to assess the association between air pollution exposure during pregnancy and the first two years of life and changes in DNA methylation or telomere length in children.
METHODS
PubMed was searched in October 2020 by using terms relative to ambient air pollution exposure, DNA methylation, telomere length and the population of interest: mother/child dyads and children. Screening and selection of the articles was completed independently by two reviewers. Thirty-two articles matched our criteria. The majority of the articles focused on gestational air pollution exposure and measured DNA methylation/telomere length in newborn cord blood or placental tissue, to study global, candidate-gene or epigenome-wide methylation patterns and/or telomere length. The number of studies in children was limited.
RESULTS
Ambient air pollution exposure during pregnancy was associated with global loss of methylation in newborn cord blood and placenta, indicating the beginning of the pregnancy as a potential period of susceptibility. Candidate gene and epigenome-wide association studies provided evidence that gestational exposure to air pollutants can lead to locus-specific changes in methylation, in newborn cord blood and placenta, particularly in genes involved in cellular responses to oxidative stress, mitochondrial function, inflammation, growth and early life development. Telomere length shortening in newborns and children was seen in relation to gestational pollutant exposure.
CONCLUSIONS
Ambient air pollution during pregnancy is associated with changes in both global and locus-specific DNA methylation and with telomere length shortening. Future studies need to test the robustness of the association across different populations, to explore potential windows of vulnerability and assess the role of the methylation and telomere length as mediators in the association between early exposure to ambient air pollutants and specific childhood health outcomes.
Topics: Air Pollutants; Air Pollution; Child; Epigenome; Female; Humans; Infant, Newborn; Maternal Exposure; Particulate Matter; Pregnancy; Telomere
PubMed: 33221306
DOI: 10.1016/j.envres.2020.110504 -
Pharmacopsychiatry Jan 2021The implementation of pharmacogenomic (PGx) testing in psychiatry remains modest, in part due to divergent perceptions of the quality and completeness of the evidence...
The implementation of pharmacogenomic (PGx) testing in psychiatry remains modest, in part due to divergent perceptions of the quality and completeness of the evidence base and diverse perspectives on the clinical utility of PGx testing among psychiatrists and other healthcare providers. Recognizing the current lack of consensus within the field, the International Society of Psychiatric Genetics assembled a group of experts to conduct a narrative synthesis of the PGx literature, prescribing guidelines, and product labels related to psychotropic medications as well as the key considerations and limitations related to the use of PGx testing in psychiatry. The group concluded that to inform medication selection and dosing of several commonly-used antidepressant and antipsychotic medications, current published evidence, prescribing guidelines, and product labels support the use of PGx testing for 2 cytochrome P450 genes (). In addition, the evidence supports testing for human leukocyte antigen genes when using the mood stabilizers carbamazepine (), oxcarbazepine (), and phenytoin (CYP2C9, HLA-B). For valproate, screening for variants in certain genes () is recommended when a mitochondrial disorder or a urea cycle disorder is suspected. Although barriers to implementing PGx testing remain to be fully resolved, the current trajectory of discovery and innovation in the field suggests these barriers will be overcome and testing will become an important tool in psychiatry.
Topics: Anticonvulsants; Antidepressive Agents; Antipsychotic Agents; Cytochrome P-450 CYP2C19; Cytochrome P-450 CYP2D6; Dose-Response Relationship, Drug; HLA Antigens; Humans; Pharmacogenomic Testing; Practice Guidelines as Topic; Psychiatry; Urea Cycle Disorders, Inborn
PubMed: 33147643
DOI: 10.1055/a-1288-1061 -
Journal of Alzheimer's Disease Reports Jun 2020Preclinical studies, clinical trials, and reviews suggest increasing 3',5'-cyclic adenosine monophosphate (cAMP) and 3',5'-cyclic guanosine monophosphate (cGMP) with... (Review)
Review
BACKGROUND
Preclinical studies, clinical trials, and reviews suggest increasing 3',5'-cyclic adenosine monophosphate (cAMP) and 3',5'-cyclic guanosine monophosphate (cGMP) with phosphodiesterase inhibitors is disease-modifying in Alzheimer's disease (AD). cAMP/protein kinase A (PKA) and cGMP/protein kinase G (PKG) signaling are disrupted in AD. cAMP/PKA and cGMP/PKG activate cAMP response element binding protein (CREB). CREB binds mitochondrial and nuclear DNA, inducing synaptogenesis, memory, and neuronal survival gene (e.g., brain-derived neurotrophic factor) and peroxisome proliferator-activated receptor- coactivator-1 (PGC1). cAMP/PKA and cGMP/PKG activate Sirtuin-1, which activates PGC1. PGC1 induces mitochondrial biogenesis and antioxidant genes (e.g.,Nrf2) and represses BACE1. cAMP and cGMP inhibit BACE1-inducing NFB and tau-phosphorylating GSK3β.
OBJECTIVE AND METHODS
We review efficacy-testing clinical trials, epidemiology, and meta-analyses to critically investigate whether phosphodiesteraseinhibitors prevent or treat AD.
RESULTS
Caffeine and cilostazol may lower AD risk. Denbufylline and sildenafil clinical trials are promising but preliminary and inconclusive. PF-04447943 and BI 409,306 are ineffective. Vinpocetine, cilostazol, and nicergoline trials are mixed. Deprenyl/selegiline trials show only short-term benefits. Broad-spectrum phosphodiesterase inhibitor propentofylline has been shown in five phase III trials to improve cognition, dementia severity, activities of daily living, and global assessment in mild-to-moderate AD patients on multiple scales, including the ADAS-Cogand the CIBIC-Plus in an 18-month phase III clinical trial. However, two books claimed based on a MedScape article an 18-month phase III trial failed, so propentofylline was discontinued. Now, propentofylline is used to treat canine cognitive dysfunction, which, like AD, involves age-associated wild-type Aβ deposition.
CONCLUSION
Phosphodiesterase inhibitors may prevent and treat AD.
PubMed: 32715279
DOI: 10.3233/ADR-200191 -
Surgery For Obesity and Related... Nov 2020Bariatric surgery is currently the most effective treatment for patients with severe obesity. Uncoupling proteins (UCP) 1, 2, and 3 play key roles in the regulation of...
BACKGROUND
Bariatric surgery is currently the most effective treatment for patients with severe obesity. Uncoupling proteins (UCP) 1, 2, and 3 play key roles in the regulation of energy balance and weight. Previous studies have suggested that changes in UCP1-3 genes could influence weight loss after bariatric surgery. However, it is still unclear if these UCPs are indeed involved in weight loss variability after surgery. Therefore, we performed a systematic review aiming to summarize the results of studies on this subject.
METHODS
A literature search was performed for all studies that evaluated associations of UCP1-3 expressions and their polymorphisms with obesity-related outcomes after bariatric surgery.
RESULTS
Twenty-six studies were eligible for inclusion in this systematic review. Among them, 18 evaluated UCP1-3 expressions while 8 studies investigated the association between UCP1-3 polymorphisms and weight loss after bariatric surgery. In general, UCP2 and UCP3 expressions in adipose tissue and skeletal muscle seem to be affected by metabolic changes of bariatric surgery, which might be influenced by the surgery type. Data on UCP1 expression in adipose tissue is still inconclusive. Only few studies investigated the association between polymorphisms in UCP1-3 genes and weight loss after bariatric surgery, with contradictory results.
CONCLUSION
Available studies suggest that changes caused by bariatric surgery could influence UCP2 and UCP3 expressions in adipose tissue and muscles, consequently affecting weight loss. However, because of the reduced number of studies, further studies are needed to confirm whether these UCPs and their polymorphisms are indeed involved in weight loss after bariatric surgery.
Topics: Bariatric Surgery; Humans; Ion Channels; Mitochondrial Proteins; Muscle, Skeletal; Uncoupling Protein 1; Uncoupling Protein 2; Uncoupling Protein 3; Weight Loss
PubMed: 32703736
DOI: 10.1016/j.soard.2020.06.015 -
Biochimica Et Biophysica Acta.... Oct 2020Malignant conversion of cancer cells requires efficient mitochondria reprogramming orchestrated by hundreds of genes. The transformation includes increased energy...
Malignant conversion of cancer cells requires efficient mitochondria reprogramming orchestrated by hundreds of genes. The transformation includes increased energy demand, biosynthesis of precursors, and reactive oxygen species needed to accelerate cell growth, proliferation, and survival. Reprogramming involves complex gene alterations that have not been methodically curated. Therefore, we systematically analyzed the literature of cancer-related genes in mitochondria. Through the analysis of >2500 PubMed abstracts and >1600 human genes, we identified 228 genes showing clear roles in cancer. Each gene was classified according to their homeostatic function, together with the pathological transitions that contribute to specific cancer hallmarks. The potential clinical relevance of these hallmarks and genes is discussed by representative examples and validated by detecting differences in gene expression levels across 16 different types of cancer. A compendium, including the gene functions and alterations underpinning cancer progression, can be explored at http://bioinformatica.mty.itesm.mx/MitoCancer.
Topics: Cell Proliferation; Cell Transformation, Neoplastic; Databases, Factual; Humans; Mitochondria; Mitochondrial Proteins; Neoplasms; Reactive Oxygen Species
PubMed: 32473387
DOI: 10.1016/j.bbadis.2020.165846 -
Pharmaceuticals (Basel, Switzerland) May 2020Epilepsy is a serious neurological disorder affecting around 70 million people globally and is characterized by spontaneous recurrent seizures. Recent evidence indicates... (Review)
Review
Epilepsy is a serious neurological disorder affecting around 70 million people globally and is characterized by spontaneous recurrent seizures. Recent evidence indicates that dysfunction in metabolic processes can lead to the alteration of neuronal and network excitability, thereby contributing to epileptogenesis. Developing a suitable animal model that can recapitulate all the clinical phenotypes of human metabolic epilepsy (ME) is crucial yet challenging. The specific environment of many symptoms as well as the primary state of the applicable neurobiology, genetics, and lack of valid biomarkers/diagnostic tests are the key factors that hinder the process of developing a suitable animal model. The present systematic review summarizes the current state of available animal models of metabolic dysfunction associated with epileptic disorders. A systematic search was performed by using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) model. A range of electronic databases, including google scholar, Springer, PubMed, ScienceDirect, and Scopus, were scanned between January 2000 and April 2020. Based on the selection criteria, 23 eligible articles were chosen and are discussed in the current review. Critical analysis of the selected literature delineated several available approaches that have been modeled into metabolic epilepsy and pointed out several drawbacks associated with the currently available models. The result describes available models of metabolic dysfunction associated with epileptic disorder, such as mitochondrial respiration deficits, Lafora disease (LD) model-altered glycogen metabolism, causing epilepsy, glucose transporter 1 (GLUT1) deficiency, adiponectin responsive seizures, phospholipid dysfunction, glutaric aciduria, mitochondrial disorders, pyruvate dehydrogenase (PDH) α-subunit gene (PDHA1), pyridoxine dependent epilepsy (PDE), BCL2-associated agonist of cell death (BAD), Kcna1 knock out (KO), and long noncoding RNAs (lncRNA) cancer susceptibility candidate 2 (lncRNA CASC2). Finally, the review highlights certain focus areas that may increase the possibilities of developing more suitable animal models and underscores the importance of the rationalization of animal models and evaluation methods for studying ME. The review also suggests the pressing need of developing precise robust animal models and evaluation methods for investigating ME.
PubMed: 32466498
DOI: 10.3390/ph13060106