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Baghaei A, Zoshk MY, Hosseini M, Fasihi H, Nassireslami E, Shayesteh S, Laripour R, Amoli AE, Heidari R, Chamanara M. Prominent genetic variants and epigenetic changes in post-traumatic stress disorder among combat veterans. Mol Biol Rep 2024; 51:325. [PMID: 38393604 DOI: 10.1007/s11033-024-09276-0] [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: 10/22/2023] [Accepted: 01/19/2024] [Indexed: 02/25/2024]
Abstract
Post-traumatic stress disorder (PTSD) is one of the most widespread and disabling psychiatric disorders among combat veterans. Substantial interindividual variability in susceptibility to PTSD suggests the presence of different risk factors for this disorder. Twin and family studies confirm genetic factors as important risk factors for PTSD. In addition to genetic factors, epigenetic factors, especially DNA methylation, can be considered as a potential mechanism in changing the risk of PTSD. So far, many genetic and epigenetic association studies have been conducted in relation to PTSD. In genetic studies, many single nucleotide polymorphisms have been identified as PTSD risk factors. Meanwhile, the variations in catecholamines-related genes, serotonin transporter and receptors, brain-derived neurotrophic factor, inflammatory factors, and apolipoprotein E are the most prominent candidates. CpG methylation in the upstream regions of many genes is also considered a PTSD risk factor. Accurate identification of genetic and epigenetic changes associated with PTSD can lead to the presentation of suitable biomarkers for susceptible individuals to this disorder. This study aimed to delineate prominent genetic variations and epigenetic changes associated with post-traumatic stress disorder in military veterans who have experienced combat, focusing on genetic and epigenetic association studies.
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Affiliation(s)
- Ahmadali Baghaei
- Trauma Research center, AJA university of Medical sciences, Tehran, Iran
| | | | - Mohsen Hosseini
- The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Fasihi
- Biomaterial and Medicinal Chemistry Research Center, AJA University of Medical Science, Tehran, Iran
| | - Ehsan Nassireslami
- Toxicology Research Center, AJA University of Medical Sciences, Tehran, Iran
- Department of Pharmacology and Toxicology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Sevda Shayesteh
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alborz University of Medical Sciences, Karaj, Iran
| | - Reza Laripour
- Social and Preventive Medicine Department, School of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Aynaz Eslami Amoli
- Trauma Research center, AJA university of Medical sciences, Tehran, Iran
| | - Reza Heidari
- Cancer Epidemiology Research Center (AJA-CERTC), AJA University of Medical Sciences, Tehran, Iran.
- Medical Biotechnology Research Center, AJA University of Medical Sciences, Tehran, Iran.
| | - Mohsen Chamanara
- Toxicology Research Center, AJA University of Medical Sciences, Tehran, Iran.
- Student research committee, AJA University of Medical Sciences, Tehran, Iran.
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Vetterlein A, Monzel M, Reuter M. Are catechol-O-methyltransferase gene polymorphisms genetic markers for pain sensitivity after all? - A review and meta-analysis. Neurosci Biobehav Rev 2023; 148:105112. [PMID: 36842714 DOI: 10.1016/j.neubiorev.2023.105112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 12/08/2022] [Accepted: 02/22/2023] [Indexed: 02/28/2023]
Abstract
The catechol-O-methyltransferase (COMT) gene has arguably been the designated pain sensitivity gene for nearly two decades. However, the literature provides inconsistent evidence. We performed several meta-analyses including k = 31 samples and n = 4631 participants thereby revealing small effects of rs4680 on pain thresholds in fibromyalgia, headache and across chronic pain conditions. Moreover, rs4680 effects were found across pain patients when affected, but not unaffected, body sites were assessed. No effect was detected for any other SNP investigated. Importantly, our results corroborate earlier findings in that we found a small effect of COMT haplotypes on pain sensitivity. Our review and meta-analysis contribute to the understanding of COMT-dependent effects on pain perception, provide insights into research issues and offer future directions. The results support the theory that rs4680 might only impact behavioural measures of pain when descending pain modulatory pathways are sufficiently challenged. After all, COMT polymorphisms are genetic markers of pain sensitivity, albeit with some limitations which are discussed with respect to their implications for research and clinical significance.
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Affiliation(s)
| | - Merlin Monzel
- Department of Psychology, University of Bonn, Germany
| | - Martin Reuter
- Department of Psychology, University of Bonn, Germany; Center for Economics and Neuroscience (CENs), Laboratory of Neurogenetics, University of Bonn, Germany
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Srivastava K, Ochuba O, Sandhu JK, Alkayyali T, Ruo SW, Waqar A, Jain A, Joseph C, Poudel S. Effect of Catechol-O-Methyltransferase Genotype Polymorphism on Neurological and Psychiatric Disorders: Progressing Towards Personalized Medicine. Cureus 2021; 13:e18311. [PMID: 34725583 PMCID: PMC8553290 DOI: 10.7759/cureus.18311] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 09/27/2021] [Indexed: 12/28/2022] Open
Abstract
Different polymorphisms of the catechol-O-methyltransferase (COMT) gene affect the COMT enzyme activity. The COMT enzyme plays a major role in the pathophysiology of various neurological and psychiatric disorders. This review article aims to discuss what recent research has discovered about the association of COMT genotype polymorphism with neurological and psychiatric disorders and the scope for the knowledge to be applied for advancement in therapeutics. We searched PubMed and Google Scholar databases and found 1656 articles. We included observational studies, clinical trials, and meta-analyses in the English language published between 2019 and 2021. We screened the articles based on the title and the abstract and found 26 relevant articles. Diseases or conditions studied primarily were schizophrenia, Parkinson’s disease, Alzheimer’s disease, substance use, and depression. This article highlights how genetics influences the susceptibility of an individual to neurological and psychiatric diseases and the variations in the specific symptoms of those diseases. The review showed that the variability in individual response to therapeutic interventions stems from the gene level. This knowledge can contribute towards the dawn of a new era of personalized medicine.
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Affiliation(s)
- Kosha Srivastava
- Neurology, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Olive Ochuba
- Internal Medicine, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Jasmine K Sandhu
- Obstetrics and Gynecology, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Tasnim Alkayyali
- Pathology, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Sheila W Ruo
- General Surgery Research, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Ahsan Waqar
- Family Medicine, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Ashish Jain
- Internal Medicine, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Christine Joseph
- Urology and Obstetrics & Gynecology, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA
| | - Sujan Poudel
- Psychiatry and Behavioral Sciences, California Institute of Behavioral Neurosciences & Psychology, Fairfield, USA.,Division of Research & Academic Affairs, Larkin Community Hospital, South Miami, USA
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Chitrala KN, Nagarkatti P, Nagarkatti M. Computational analysis of deleterious single nucleotide polymorphisms in catechol O-Methyltransferase conferring risk to post-traumatic stress disorder. J Psychiatr Res 2021; 138:207-218. [PMID: 33865170 PMCID: PMC8969201 DOI: 10.1016/j.jpsychires.2021.03.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Revised: 03/18/2021] [Accepted: 03/24/2021] [Indexed: 10/21/2022]
Abstract
Post-traumatic stress disorder (PTSD) is one of the prevalent neurological disorder which is drawing increased attention over the past few decades. Major risk factors for PTSD can be categorized into environmental and genetic factors. Among the genetic risk factors, polymorphisms in the catechol-O-methyltransferase (COMT) gene is known to be associated with the risk for PTSD. In the present study, we analysed the impact of deleterious single nucleotide polymorphisms (SNPs) in the COMT gene conferring risk to PTSD using computational based approaches followed by molecular dynamic simulations. The data on COMT gene associated with PTSD were collected from several databases including Online Mendelian Inheritance in Man (OMIM) search. Datasets related to SNP were downloaded from the dbSNP database. To study the structural and dynamic effects of COMT wild type and mutant forms, we performed molecular dynamics simulations (MD simulations) at a time scale of 300 ns. Results from screening the SNPs using the computational tools SIFT and Polyphen-2 demonstrated that the SNP rs4680 (V158M) in COMT has a deleterious effect with phenotype in PTSD. Results from the MD simulations showed that there is some major fluctuations in the structural features including root mean square deviation (RMSD), radius of gyration (Rg), root mean square fluctuation (RMSF) and secondary structural elements including α-helices, sheets and turns between wild-type (WT) and mutant forms of COMT protein. In conclusion, our study provides novel insights into the deleterious effects and impact of V158M mutation on COMT protein structure which plays a key role in PTSD.
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Affiliation(s)
- Kumaraswamy Naidu Chitrala
- Dept. of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, SC, 29208, USA; Fels Cancer Institute for Personalized Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, 19140, USA.
| | - Prakash Nagarkatti
- Dept. of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, SC, 29208, USA
| | - Mitzi Nagarkatti
- Dept. of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, SC, 29208, USA
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Tunbridge EM, Narajos M, Harrison CH, Beresford C, Cipriani A, Harrison PJ. Which Dopamine Polymorphisms Are Functional? Systematic Review and Meta-analysis of COMT, DAT, DBH, DDC, DRD1-5, MAOA, MAOB, TH, VMAT1, and VMAT2. Biol Psychiatry 2019; 86:608-620. [PMID: 31303260 DOI: 10.1016/j.biopsych.2019.05.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 04/11/2019] [Accepted: 05/01/2019] [Indexed: 01/19/2023]
Abstract
BACKGROUND Many polymorphisms in dopamine genes are reported to affect cognitive, imaging, or clinical phenotypes. It is often inferred or assumed that such associations are causal, mediated by a direct effect of the polymorphism on the gene product itself. However, the supporting evidence is not always clear. METHODS We conducted systematic reviews and meta-analyses to assess the empirical evidence for functional polymorphisms in genes encoding dopaminergic enzymes (COMT, DBH, DDC, MAOA, MAOB, and TH), dopamine receptors (DRD1, DRD2, DRD3, DRD4, and DRD5), the dopamine transporter (DAT), and vesicular transporters (VMAT1 and VMAT2). We defined functionality as an effect of the polymorphism on the expression, abundance, activity, or affinity of the gene product. RESULTS We screened 22,728 articles and identified 255 eligible studies. We found robust and medium to large effects for polymorphisms in 4 genes. For catechol-O-methyltransferase (COMT), the Val158Met polymorphism (rs4680) markedly affected enzyme activity, protein abundance, and protein stability. Dopamine β-hydroxylase (DBH) activity was associated with rs1611115, rs2519152, and the DBH-STR polymorphism. Monoamine oxidase A (MAOA) activity was associated with a 5' VNTR polymorphism. Dopamine D2 receptor (DRD2) binding was influenced by the Taq1A (rs1800497) polymorphism, and rs1076560 affected DRD2 splicing. CONCLUSIONS Some widely studied dopaminergic polymorphisms clearly and substantially affect the abundance or activity of the encoded gene product. However, for other polymorphisms, evidence of such an association is negative, inconclusive, or lacking. These findings are relevant when selecting polymorphisms as "markers" of dopamine function, and for interpreting the biological plausibility of associations between these polymorphisms and aspects of brain function or dysfunction.
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Affiliation(s)
- Elizabeth M Tunbridge
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, United Kingdom; Oxford Health NHS Foundation Trust, Oxford, United Kingdom
| | - Marco Narajos
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, United Kingdom
| | | | - Charles Beresford
- Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | - Andrea Cipriani
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, United Kingdom; Oxford Health NHS Foundation Trust, Oxford, United Kingdom
| | - Paul J Harrison
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, United Kingdom; Oxford Health NHS Foundation Trust, Oxford, United Kingdom.
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Bastos P, Gomes T, Ribeiro L. Catechol-O-Methyltransferase (COMT): An Update on Its Role in Cancer, Neurological and Cardiovascular Diseases. Rev Physiol Biochem Pharmacol 2017; 173:1-39. [DOI: 10.1007/112_2017_2] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Patra N, Ioannidis EI, Kulik HJ. Computational Investigation of the Interplay of Substrate Positioning and Reactivity in Catechol O-Methyltransferase. PLoS One 2016; 11:e0161868. [PMID: 27564542 PMCID: PMC5001633 DOI: 10.1371/journal.pone.0161868] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/13/2016] [Indexed: 12/27/2022] Open
Abstract
Catechol O-methyltransferase (COMT) is a SAM- and Mg2+-dependent methyltransferase that regulates neurotransmitters through methylation. Simulations and experiments have identified divergent catecholamine substrate orientations in the COMT active site: molecular dynamics simulations have favored a monodentate coordination of catecholate substrates to the active site Mg2+, and crystal structures instead preserve bidentate coordination along with short (2.65 Å) methyl donor-acceptor distances. We carry out longer dynamics (up to 350 ns) to quantify interconversion between bidentate and monodentate binding poses. We provide a systematic determination of the relative free energy of the monodentate and bidentate structures in order to identify whether structural differences alter the nature of the methyl transfer mechanism and source of enzymatic rate enhancement. We demonstrate that the bidentate and monodentate binding modes are close in energy but separated by a 7 kcal/mol free energy barrier. Analysis of interactions in the two binding modes reveals that the driving force for monodentate catecholate orientations in classical molecular dynamics simulations is derived from stronger electrostatic stabilization afforded by alternate Mg2+ coordination with strongly charged active site carboxylates. Mixed semi-empirical-classical (SQM/MM) substrate C-O distances (2.7 Å) for the bidentate case are in excellent agreement with COMT X-ray crystal structures, as long as charge transfer between the substrates, Mg2+, and surrounding ligands is permitted. SQM/MM free energy barriers for methyl transfer from bidentate and monodentate catecholate configurations are comparable at around 21-22 kcal/mol, in good agreement with experiment (18-19 kcal/mol). Overall, the work suggests that both binding poses are viable for methyl transfer, and accurate descriptions of charge transfer and electrostatics are needed to provide balanced relative barriers when multiple binding poses are accessible, for example in other transferases.
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Affiliation(s)
- Niladri Patra
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, United States of America
| | - Efthymios I. Ioannidis
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, United States of America
| | - Heather J. Kulik
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, United States of America
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mRNA Capping by Venezuelan Equine Encephalitis Virus nsP1: Functional Characterization and Implications for Antiviral Research. J Virol 2015; 89:8292-303. [PMID: 26041283 DOI: 10.1128/jvi.00599-15] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 05/19/2015] [Indexed: 12/26/2022] Open
Abstract
UNLABELLED Alphaviruses are known to possess a unique viral mRNA capping mechanism involving the viral nonstructural protein nsP1. This enzyme harbors methyltransferase (MTase) and nsP1 guanylylation (GT) activities catalyzing the transfer of the methyl group from S-adenosylmethionine (AdoMet) to the N7 position of a GTP molecule followed by the formation of an m(7)GMP-nsP1 adduct. Subsequent transfer of m(7)GMP onto the 5' end of the viral mRNA has not been demonstrated in vitro yet. Here we report the biochemical characterization of Venezuelan equine encephalitis virus (VEEV) nsP1. We have developed enzymatic assays uncoupling the different reactions steps catalyzed by nsP1. The MTase and GT reaction activities were followed using a nonhydrolyzable GTP (GIDP) substrate and an original Western blot assay using anti-m3G/m(7)G-cap monoclonal antibody, respectively. The GT reaction is stimulated by S-adenosyl-l-homocysteine (Ado-Hcy), the product of the preceding MTase reaction, and metallic ions. The covalent linking between nsP1 and m(7)GMP involves a phosphamide bond between the nucleotide and a histidine residue. Final guanylyltransfer onto RNA was observed for the first time with an alphavirus nsP1 using a 5'-diphosphate RNA oligonucleotide whose sequence corresponds to the 5' end of the viral genome. Alanine scanning mutagenesis of residues H37, H45, D63, E118, Y285, D354, R365, N369, and N375 revealed their respective roles in MT and GT reactions. Finally, the inhibitory effects of sinefungin, aurintricarboxylic acid (ATA), and ribavirin triphosphate on MTase and capping reactions were investigated, providing possible avenues for antiviral research. IMPORTANCE Emergence or reemergence of alphaviruses represents a serious health concern, and the elucidation of their replication mechanisms is a prerequisite for the development of specific inhibitors targeting viral enzymes. In particular, alphaviruses are able, through an original reaction sequence, to add to their mRNA a cap required for their protection against cellular nucleases and initiation of viral proteins translation. In this study, the capping of a 5' diphosphate synthetic RNA mimicking the 5' end of an alphavirus mRNA was observed in vitro for the first time. The different steps for this capping are performed by the nonstructural protein 1 (nsP1). Reference compounds known to target the viral capping inhibited nsP1 enzymatic functions, highlighting the value of this enzyme in antiviral development.
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Behbahani P, Kazemi-Nezhad SR, Foroughmand AM, Ahmadi L. Association study of single nucleotide polymorphism rs165599 of COMT gene, with schizophrenia and bipolar mood disorder in the south-west of Iran. MOLECULAR BIOLOGY RESEARCH COMMUNICATIONS 2015; 4:67-72. [PMID: 27843998 PMCID: PMC5019293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Linkage studies and epidemiological findings indicate that some possible genes in schizophrenia (SCZ) and bipolar mood disorder (BPD) are common. Numerous evidences for linkage of two diseases on chromosome 22 have been found. These findings suggest that one or more genes in the 22q11.21 region may be involved in the development of both disorders. In the present case-control study, association between the mentioned disorders and a genetic polymorphism (rs165599) of catechol O- methyltransferase (COMT, OMIM: 116790) was studied. Here 100 BPD patients, 100SCZ patients, and 100 healthy controls were included in the study. The samples were matched in terms of gender and ethnicity. Statistical analysis showed that there was a significant association this polymorphism and risk of SCZ. The AG (OR=7.41, 95% CI: 3.21-17.1, P<0.001) and GG genotypes (OR=13.9, 95% CI: 5.61-34.4, P<0.001) increased the risk of SCZ compared with the GG genotypes. The AG (OR=14.3, 95% CI: 4.16-49.4, P<0.001) and AA genotypes (OR=54.2, 95% CI: 15.3-191, P<0.001) significantly associated with the risk of BPD. The risk of SCZ (x2=37.4, P<0.001) and BPD (x2=66.2, P<0.001) significantly increased as a function of numbers of the A allele. The present study revealed that this polymorphism associated with risks of SCZ, and BPD.
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Cacabelos R, Cacabelos P, Aliev G. Genomics of schizophrenia and pharmacogenomics of antipsychotic drugs. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/ojpsych.2013.31008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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11
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Haerian MS, Baum L, Haerian BS. Association of 8q24.21 loci with the risk of colorectal cancer: a systematic review and meta-analysis. J Gastroenterol Hepatol 2011; 26:1475-84. [PMID: 21722176 DOI: 10.1111/j.1440-1746.2011.06831.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND AND AIM Recent genome-wide association studies of colorectal cancer (CRC) have identified rs6983267 and trs10505477 polymorphisms as key loci in the 8q24 region to be associated with CRC. In the present study, we performed a meta-analysis to determine whether these loci are risk factors for susceptibility to CRC. METHODS We meta-analyzed the 22 included studies (47 003 cases and 45 754 controls) that evaluated the association of rs6983267 and trs10505477 with CRC under alternative genetic models. RESULTS A meta-analysis of the pooled data showed allelic and genotypic association of the rs6983267 polymorphism with CRC risk in Asians, Europeans, and European-Americans. A subanalysis of the US studies showed negative results in the studies with non-identified ethnicity of the patients. A meta-analysis of included studies of rs10505477 polymorphisms identified allelic and genotypic associations with CRC risk in the US patients. A further meta-analysis of the US studies demonstrated positive results in the studies with non-identified ethnicity of the samples. CONCLUSION Our data suggested that the rs6983267 G > T polymorphism is a risk factor for CRC in Asians, Europeans, and Americans with European ancestry.
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Affiliation(s)
- Monir Sadat Haerian
- Research Center for Gastroenterology and Liver Disease, Shaheed Beheshti University, Tehran, Iran
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Abstract
Schizophrenia (SCZ) is among the most disabling of mental disorders. Several neurobiological hypotheses have been postulated as responsible for SCZ pathogenesis: polygenic/multifactorial genomic defects, intrauterine and perinatal environment-genome interactions, neurodevelopmental defects, dopaminergic, cholinergic, serotonergic, gamma-aminobutiric acid (GABAergic), neuropeptidergic and glutamatergic/N-Methyl-D-Aspartate (NMDA) dysfunctions, seasonal infection, neuroimmune dysfunction, and epigenetic dysregulation. SCZ has a heritability estimated at 60-90%. Genetic studies in SCZ have revealed the presence of chromosome anomalies, copy number variants, multiple single-nucleotide polymorphisms of susceptibility distributed across the human genome, aberrant single nucleotide polymorphisms (SNPs) in microRNA genes, mitochondrial DNA mutations, and epigenetic phenomena. Pharmacogenetic studies of psychotropic drug response have focused on determining the relationship between variation in specific candidate genes and the positive and adverse effects of drug treatment. Approximately, 18% of neuroleptics are major substrates of CYP1A2 enzymes, 40% of CYP2D6, and 23% of CYP3A4; 24% of antidepressants are major substrates of CYP1A2 enzymes, 5% of CYP2B6, 38% of CYP2C19, 85% of CYP2D6, and 38% of CYP3A4; 7% of benzodiazepines are major substrates of CYP2C19 enzymes, 20% of CYP2D6, and 95% of CYP3A4. About 10-20% of Western populations are defective in genes of the CYP superfamily. Only 26% of Southern Europeans are pure extensive metabolizers for the trigenic cluster integrated by the CYP2D6+CYP2C19+CYP2C9 genes. The pharmacogenomic response of SCZ patients to conventional psychotropic drugs also depends on genetic variants associated with SCZ-related genes. Consequently, the incorporation of pharmacogenomic procedures both to drugs in development and drugs on the market would help to optimize therapeutics in SCZ and other central nervous system (CNS) disorders.
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Affiliation(s)
- Ramón Cacabelos
- EuroEspes Biomedical Research Center, 15165-Bergondo, Coruña, Spain.
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Lazar NL, Neufeld RWJ, Cain DP. Contribution of nonprimate animal models in understanding the etiology of schizophrenia. J Psychiatry Neurosci 2011; 36:E5-29. [PMID: 21247514 PMCID: PMC3120891 DOI: 10.1503/jpn.100054] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Schizophrenia is a severe psychiatric disorder that is characterized by positive and negative symptoms and cognitive impairments. The etiology of the disorder is complex, and it is thought to follow a multifactorial threshold model of inheritance with genetic and neurodevelop mental contributions to risk. Human studies are particularly useful in capturing the richness of the phenotype, but they are often limited to the use of correlational approaches. By assessing behavioural abnormalities in both humans and rodents, nonprimate animal models of schizophrenia provide unique insight into the etiology and mechanisms of the disorder. This review discusses the phenomenology and etiology of schizophrenia and the contribution of current nonprimate animal models with an emphasis on how research with models of neuro transmitter dysregulation, environmental risk factors, neurodevelopmental disruption and genetic risk factors can complement the literature on schizophrenia in humans.
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Affiliation(s)
- Noah L Lazar
- Department of Psychology, University of Western Ontario, London, Ont.
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14
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Huang X, Gao D, Zhan CG. Computational design of a thermostable mutant of cocaine esterase via molecular dynamics simulations. Org Biomol Chem 2011; 9:4138-43. [PMID: 21373712 PMCID: PMC4365906 DOI: 10.1039/c0ob00972e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cocaine esterase (CocE) has been known as the most efficient native enzyme for metabolizing naturally occurring cocaine. A major obstacle to the clinical application of CocE is the thermoinstability of native CocE with a half-life of only ∼11 min at physiological temperature (37 °C). It is highly desirable to develop a thermostable mutant of CocE for therapeutic treatment of cocaine overdose and addiction. To establish a structure-thermostability relationship, we carried out molecular dynamics (MD) simulations at 400 K on wild-type CocE and previously known thermostable mutants, demonstrating that the thermostability of the active form of the enzyme correlates with the fluctuation (characterized as the root-mean square deviation and root-mean square fluctuation of atomic positions) of the catalytic residues (Y44, S117, Y118, H287, and D259) in the simulated enzyme. In light of the structure-thermostability correlation, further computational modelling including MD simulations at 400 K predicted that the active site structure of the L169K mutant should be more thermostable. The prediction has been confirmed by wet experimental tests showing that the active form of the L169K mutant had a half-life of 570 min at 37 °C, which is significantly longer than those of the wild-type and previously known thermostable mutants. The encouraging outcome suggests that the high-temperature MD simulations and the structure-thermostability relationship may be considered as a valuable tool for the computational design of thermostable mutants of an enzyme.
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Affiliation(s)
- Xiaoqin Huang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, Kentucky 40536
| | - Daquan Gao
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, Kentucky 40536
| | - Chang-Guo Zhan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, Kentucky 40536
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van der Kamp MW, Daggett V. Molecular dynamics as an approach to study prion protein misfolding and the effect of pathogenic mutations. Top Curr Chem (Cham) 2011; 305:169-97. [PMID: 21526434 DOI: 10.1007/128_2011_158] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Computer simulation of protein dynamics offers unique high-resolution information that complements experiment. Using experimentally derived structures of the natively folded prion protein (PrP), physically realistic dynamics and conformational changes can be simulated, including the initial steps of misfolding. By introducing mutations in silico, the effect of pathogenic mutations on PrP conformation and dynamics can be assessed. Here, we briefly introduce molecular dynamics methods and review the application of molecular dynamics simulations to obtain insight into various aspects of the PrP, including the mechanism of misfolding, the response to changes in the environment, and the influence of disease-related mutations.
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Affiliation(s)
- Marc W van der Kamp
- Department of Bioengineering, University of Washington, Seattle, WA 98195-5013, USA
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van der Kamp MW, Daggett V. Pathogenic mutations in the hydrophobic core of the human prion protein can promote structural instability and misfolding. J Mol Biol 2010; 404:732-48. [PMID: 20932979 PMCID: PMC2994014 DOI: 10.1016/j.jmb.2010.09.060] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Accepted: 09/27/2010] [Indexed: 11/21/2022]
Abstract
Transmissible spongiform encephalopathies, or prion diseases, are caused by misfolding and aggregation of the prion protein PrP. These diseases can be hereditary in humans and four of the many disease-associated missense mutants of PrP are in the hydrophobic core: V180I, F198S, V203I and V210I. The T183A mutation is related to the hydrophobic core mutants as it is close to the hydrophobic core and known to cause instability. We used extensive molecular dynamics simulations of these five PrP mutants to compare their dynamics and conformations to those of the wild type PrP. The simulations highlight the changes that occur upon introduction of mutations and help to rationalize experimental findings. Changes can occur around the mutation site, but they can also be propagated over long distances. In particular, the F198S and T183A mutations lead to increased flexibility in parts of the structure that are normally stable, and the short β-sheet moves away from the rest of the protein. Mutations V180I, V210I and, to a lesser extent, V203I cause changes similar to those observed upon lowering the pH, which has been linked to misfolding. Early misfolding is observed in one V180I simulation. Overall, mutations in the hydrophobic core have a significant effect on the dynamics and stability of PrP, including the propensity to misfold, which helps to explain their role in the development of familial prion diseases.
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Affiliation(s)
- Marc W. van der Kamp
- Department of Bioengineering, University of Washington, Seattle, Washington, USA 98195-5013
| | - Valerie Daggett
- Department of Bioengineering, University of Washington, Seattle, Washington, USA 98195-5013
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Zhao A, Cheng Y, Li X, Li Q, Wang L, Xu J, Xiang Y, Xing Q, He L, Zhao X. Promoter hypomethylation of COMT in human placenta is not associated with the development of pre-eclampsia. Mol Hum Reprod 2010; 17:199-206. [PMID: 21047975 DOI: 10.1093/molehr/gaq092] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Disruption of the Catechol-O-methyltransferase (COMT) gene has been shown to be involved in pre-eclampsia (PE). To investigate whether two promoters of the COMT gene are differentially regulated by methylation in PE patients, we have analyzed the genomic DNA extracted from placenta (cases n = 16; controls n = 21), maternal peripheral blood (cases n = 4; controls n = 6) and umbilical cord blood (cases n = 8; controls n = 8) of women with PE and women with normal pregnancy. Bisulfite sequencing identified the predominantly unmethylated MB-COMT promoter in placenta, maternal peripheral blood and umbilical cord blood samples (PE and control). Subsequent quantitative MassArray data confirmed a significant tissue-specific hypomethylation of the S-COMT promoter in placenta (mean = 28.6%) when compared with its densely methylated patterns in blood samples (mean = 74.5%, P < 0.001), consistent with the sequencing data. However, no PE-specific methylation difference was found between cases and controls either in placenta or in blood samples. Moreover, none of the clinical characteristics had an effect on the methylation status of the S-COMT promoter. This study does not support a causal link between methylation regulation of COMT promoters and PE. However, the observed placenta-specific S-COMT promoter may be a potential marker for early prediction of PE in maternal plasma, although this remains to be further evaluated.
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Affiliation(s)
- Arman Zhao
- Institute of Biomedical Sciences, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
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Dynameomics: a comprehensive database of protein dynamics. Structure 2010; 18:423-35. [PMID: 20399180 DOI: 10.1016/j.str.2010.01.012] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 01/17/2010] [Accepted: 01/21/2010] [Indexed: 12/15/2022]
Abstract
The dynamic behavior of proteins is important for an understanding of their function and folding. We have performed molecular dynamics simulations of the native state and unfolding pathways of over 2000 protein/peptide systems (approximately 11,000 independent simulations) representing the majority of folds in globular proteins. These data are stored and organized using an innovative database approach, which can be mined to obtain both general and specific information about the dynamics and folding/unfolding of proteins, relevant subsets thereof, and individual proteins. Here we describe the project in general terms and the type of information contained in the database. Then we provide examples of mining the database for information relevant to protein folding, structure building, the effect of single-nucleotide polymorphisms, and drug design. The native state simulation data and corresponding analyses for the 100 most populated metafolds, together with related resources, are publicly accessible through http://www.dynameomics.org.
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Rutherford K, Daggett V. Polymorphisms and disease: hotspots of inactivation in methyltransferases. Trends Biochem Sci 2010; 35:531-8. [PMID: 20382027 DOI: 10.1016/j.tibs.2010.03.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 03/10/2010] [Accepted: 03/10/2010] [Indexed: 01/13/2023]
Abstract
Methyltransferases catalyze the methylation processes essential for protein/DNA repair, transcriptional regulation, and drug metabolism in vivo. More than 500 human methyltransferase polymorphisms have been identified, many of which are linked to disease. We mapped all available coding polymorphisms of seven methyltransferases onto their structures to address their structural significance, and identified a polymorphic hotspot ∼20Å from the active site in four of the proteins. Molecular dynamics simulations of these proteins reveal a common mechanism of destabilization: the mutations alter important side-chain contacts within the polymorphic site that are propagated through the protein, thereby distorting the active site. We propose that this hotspot might have arisen to modulate enzymatic activity, with decreased activity actually conferring an advantage in three of the four methyltransferases.
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Affiliation(s)
- Karen Rutherford
- Department of Biochemistry, Box 355013, University of Washington, Seattle WA 98195-5013, USA
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