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1.
Molecules ; 28(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446769

RESUMO

Potentilla nepalensis Hook is a perennial Himalayan medicinal herb of the Rosaceae family. The present study aimed to evaluate biological activities such as the antioxidant, antibacterial, and anticancer activities of roots and shoots of P. nepalensis and its synergistic antibacterial activity with antibacterial drugs. Folin-Ciocalteau and aluminium chloride methods were used for the calculation of total phenolic (TPC) and flavonoid content (TFC). A DPPH radical scavenging assay and broth dilution method were used for the determination of the antioxidant and antibacterial activity of the root and shoot extracts of P. nepalensis. Cytotoxic activity was determined using a colorimetric MTT assay. Further, phytochemical characterization of the root and shoot extracts was performed using the Gas chromatography-mass spectrophotometry (GC-MS) method. The TPC and TFC were found to be higher in the methanolic root extract of P. nepalensis. The methanolic shoot extract of P. nepalensis showed good antioxidant activity, while then-hexane root extract of P. nepalensis showed strong cytotoxic activity against tested SK-MEL-28 cells. Subsequently, in silico molecular docking studies of the identified bioactive compounds predicted potential anticancer properties. This study can lead to the production of new herbal medicines for various diseases employing P. nepalensis, leading to the creation of new medications.


Assuntos
Melanoma , Plantas Medicinais , Potentilla , Simulação de Acoplamento Molecular , Antioxidantes/química , Potentilla/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Fenóis/química , Antibacterianos/farmacologia , Metanol/química , Melanoma/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Computadores
2.
Ann Neurol ; 94(4): 713-726, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37486023

RESUMO

OBJECTIVE: The objective of this study was to aggregate data for the first genomewide association study meta-analysis of cluster headache, to identify genetic risk variants, and gain biological insights. METHODS: A total of 4,777 cases (3,348 men and 1,429 women) with clinically diagnosed cluster headache were recruited from 10 European and 1 East Asian cohorts. We first performed an inverse-variance genomewide association meta-analysis of 4,043 cases and 21,729 controls of European ancestry. In a secondary trans-ancestry meta-analysis, we included 734 cases and 9,846 controls of East Asian ancestry. Candidate causal genes were prioritized by 5 complementary methods: expression quantitative trait loci, transcriptome-wide association, fine-mapping of causal gene sets, genetically driven DNA methylation, and effects on protein structure. Gene set and tissue enrichment analyses, genetic correlation, genetic risk score analysis, and Mendelian randomization were part of the downstream analyses. RESULTS: The estimated single nucleotide polymorphism (SNP)-based heritability of cluster headache was 14.5%. We identified 9 independent signals in 7 genomewide significant loci in the primary meta-analysis, and one additional locus in the trans-ethnic meta-analysis. Five of the loci were previously known. The 20 genes prioritized as potentially causal for cluster headache showed enrichment to artery and brain tissue. Cluster headache was genetically correlated with cigarette smoking, risk-taking behavior, attention deficit hyperactivity disorder (ADHD), depression, and musculoskeletal pain. Mendelian randomization analysis indicated a causal effect of cigarette smoking intensity on cluster headache. Three of the identified loci were shared with migraine. INTERPRETATION: This first genomewide association study meta-analysis gives clues to the biological basis of cluster headache and indicates that smoking is a causal risk factor. ANN NEUROL 2023;94:713-726.


Assuntos
Cefaleia Histamínica , Transtornos de Enxaqueca , Masculino , Humanos , Feminino , Cefaleia Histamínica/epidemiologia , Cefaleia Histamínica/genética , Fatores de Risco , Estudo de Associação Genômica Ampla , Fumar/efeitos adversos , Fumar/genética , Polimorfismo de Nucleotídeo Único/genética , Predisposição Genética para Doença/genética
3.
Brain ; 146(7): 2723-2729, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-36797998

RESUMO

CAG repeat expansions in exon 1 of the AR gene on the X chromosome cause spinal and bulbar muscular atrophy, a male-specific progressive neuromuscular disorder associated with a variety of extra-neurological symptoms. The disease has a reported male prevalence of approximately 1:30 000 or less, but the AR repeat expansion frequency is unknown. We established a pipeline, which combines the use of the ExpansionHunter tool and visual validation, to detect AR CAG expansion on whole-genome sequencing data, benchmarked it to fragment PCR sizing, and applied it to 74 277 unrelated individuals from four large cohorts. Our pipeline showed sensitivity of 100% [95% confidence interval (CI) 90.8-100%], specificity of 99% (95% CI 94.2-99.7%), and a positive predictive value of 97.4% (95% CI 84.4-99.6%). We found the mutation frequency to be 1:3182 (95% CI 1:2309-1:4386, n = 117 734) X chromosomes-10 times more frequent than the reported disease prevalence. Modelling using the novel mutation frequency led to estimate disease prevalence of 1:6887 males, more than four times more frequent than the reported disease prevalence. This discrepancy is possibly due to underdiagnosis of this neuromuscular condition, reduced penetrance, and/or pleomorphic clinical manifestations.


Assuntos
Atrofia Muscular Espinal , Receptores Androgênicos , Humanos , Masculino , Receptores Androgênicos/genética , Atrofia Muscular Espinal/genética , Atrofia Muscular , Reação em Cadeia da Polimerase , Expansão das Repetições de Trinucleotídeos/genética
4.
Comput Biol Med ; 155: 106644, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36774886

RESUMO

It has been indicated that leukemic stem cells (LSCs), a subset of leukaemia cells, are responsible for therapy resistance and relapse in acute myeloid leukaemia (AML). Therefore, the current study aimed to discover an LSC biomarker in AML patients and identify a natural compound that may target the same. By performing the different gene expression analyses, we identified 12 up-regulated and 192 down-regulated genes in LSCs of AML compared to normal bone marrow-derived HSCs. Further STRING interaction, GO enrichment and KEGG pathway analysis were carried out to top hub genes. Wilms' tumour-1 (WT1) transcription factor was pointed out as the top hub gene and a potential biomarker for LSCs in AML. For the targeted inhibition of WT1, we performed screening and stimulation of potential natural compounds. The results revealed Gallic acid (GA) and Chlorogenic acid (CA) as promising WT1 inhibitors. In-vitro validation of cytotoxic effects of both GA and CA on THP-1 and HL-60 cell lines suggested that both these compounds inhibited cell proliferation. Still, GA has a more cytotoxic effect compared to CA. Next, we performed cell cycle analysis and apoptosis analysis and found that both compounds arrested cells in G0/G1 phase and induced apoptosis in both cell lines. Surprisingly, a significant decrease in colony formation and cell migration was also observed. However, GA gave more promising results in all cellular assays than CA. Furthermore, we studied the mRNA expression of WT1 and BCL2, which are transcriptionally activated by it. We found that GA significantly downregulated both these genes compared to CA. Our results suggested that GA is a potential inhibitor of WT1 and might be an excellent anti-LSCs natural drug for AML patients.


Assuntos
Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Biomarcadores/metabolismo , Células-Tronco/metabolismo , Compostos Fitoquímicos/farmacologia , Células-Tronco Neoplásicas/metabolismo
5.
PLoS Biol ; 21(2): e3002022, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36763683

RESUMO

The past 20 years of research has elucidated new innate immune sensing and cell death pathways with disease relevance. Future molecular characterization of these pathways and their crosstalk and functional redundancies will aid in development of therapeutic strategies.


Assuntos
Imunidade Inata , Morte Celular
6.
Proteins ; 91(2): 277-289, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36116110

RESUMO

Understanding how MHC class II (MHC-II) binding peptides with differing lengths exhibit specific interaction at the core and extended sites within the large MHC-II pocket is a very important aspect of immunological research for designing peptides. Certain efforts were made to generate peptide conformations amenable for MHC-II binding and calculate the binding energy of such complex formation but not directed toward developing a relationship between the peptide conformation in MHC-II structures and the binding affinity (BA) (IC50 ). We present here a machine-learning approach to calculate the BA of the peptides within the MHC-II pocket for HLA-DRA1, HLA-DRB1, HLA-DP, and HLA-DQ allotypes. Instead of generating ensembles of peptide conformations conventionally, the biased mode of conformations was created by considering the peptides in the crystal structures of pMHC-II complexes as the templates, followed by site-directed peptide docking. The structural interaction fingerprints generated from such docked pMHC-II structures along with the Moran autocorrelation descriptors were trained using a random forest regressor specific to each MHC-II peptide lengths (9-19). The entire workflow is automated using Linux shell and Perl scripts to promote the utilization of MHC2AffyPred program to any characterized MHC-II allotypes and is made for free access at https://github.com/SiddhiJani/MHC2AffyPred. The MHC2AffyPred attained better performance (correlation coefficient [CC] of .612-.898) than MHCII3D (.03-.594) and NetMHCIIpan-3.2 (.289-.692) programs in the HLA-DRA1, HLA-DRB1 types. Similarly, the MHC2AffyPred program achieved CC between .91 and .98 for HLA-DP and HLA-DQ peptides (13-mer to 17-mer). Further, a case study on MHC-II binding 15-mer peptides of severe acute respiratory syndrome coronavirus-2 showed very close competency in computing the IC50 values compared to the sequence-based NetMHCIIpan v3.2 and v4.0 programs with a correlation of .998 and .570, respectively.


Assuntos
COVID-19 , Humanos , Cadeias HLA-DRB1/metabolismo , Peptídeos/química , Antígenos HLA-DP/química , Antígenos HLA-DP/metabolismo , Antígenos HLA-DQ/química , Antígenos HLA-DQ/metabolismo , Aprendizado de Máquina , Ligação Proteica
7.
J Comput Chem ; 43(12): 847-863, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35301752

RESUMO

Structure-based pharmacophore models are often developed by selecting a single protein-ligand complex with good resolution and better binding affinity data which prevents the analysis of other structures having a similar potential to act as better templates. PharmRF is a pharmacophore-based scoring function for selecting the best crystal structures with the potential to attain high enrichment rates in pharmacophore-based virtual screening prospectively. The PharmRF scoring function is trained and tested on the PDBbind v2018 protein-ligand complex dataset and employs a random forest regressor to correlate protein pocket descriptors and ligand pharmacophoric elements with binding affinity. PharmRF score represents the calculated binding affinity which identifies high-affinity ligands by thorough pruning of all the PDB entries available for a particular protein of interest with a high PharmRF score. Ligands with high PharmRF scores can provide a better basis for structure-based pharmacophore enumerations with a better enrichment rate. Evaluated on 10 protein-ligand systems of the DUD-E dataset, PharmRF achieved superior performance (average success rate: 77.61%, median success rate: 87.16%) than Vina docking score (75.47%, 79.39%). PharmRF was further evaluated using the CASF-2016 benchmark set yielding a moderate correlation of 0.591 with experimental binding affinity, similar in performance to 25 scoring functions tested on this dataset. Independent assessment of PharmRF on 8 protein-ligand systems of LIT-PCBA dataset exhibited average and median success rates of 57.55% and 74.72% with 4 targets attaining success rate > 90%. The PharmRF scoring model, scripts, and related resources can be accessed at https://github.com/Prasanth-Kumar87/PharmRF.


Assuntos
Aprendizado de Máquina , Proteínas , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Proteínas/química
8.
Chem Biol Interact ; 353: 109774, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34958756

RESUMO

Poor prognosis and metastasis have been recognized as the major cause of breast cancer related deaths worldwide. Recent experimental evidence has shown that Hsp90, the prime chaperone, is overexpressed in many cancers and is responsible if reducing the 5-year survival rate of cancer patients. Therefore, targeted inhibition of Hsp90 may be a new and effective way to target cancer as well as enhancing therapeutic outcomes. In the present study, screening and simulation of potential natural compounds result in the identification of theaflavin-3-gallate as a promising inhibitory compound of Hsp90. Further in-vitro validation of the cytotoxic effect of theaflavin-3-gallate in human breast carcinoma cell line MCF7 and normal cell line MCF10A revealed that theaflavin-3-gallate significantly inhibited the cell proliferation of MCF7 cells whereas no cytotoxic effect was observed on MCF10A cells. We also found that theaflavin-3-gallate significantly induced programmed cell death by arresting cells in the G2/M phase of the cell cycle. A significant decrease in cell migration and colony formation by theaflavin-3-gallate treatment was also observed in MCF7 cells. Furthermore, theaflavin-3-gallate significantly downregulated the mRNA expression patterns of the HSP90, MMP9, VEGFA, and SPP1 genes. Collectively, our results demonstrated theaflavin-3-gallate as a potential natural Hsp90 inhibitor that can be used to enhance the therapeutic efficacy of existing breast cancer therapies and improve overall survival of breast cancer patients.


Assuntos
Biflavonoides/farmacologia , Catequina/farmacologia , Proliferação de Células/efeitos dos fármacos , Ácido Gálico/análogos & derivados , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Biflavonoides/química , Biflavonoides/metabolismo , Sítios de Ligação , Catequina/química , Catequina/metabolismo , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Ácido Gálico/química , Ácido Gálico/metabolismo , Ácido Gálico/farmacologia , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Simulação de Acoplamento Molecular , Transcriptoma/efeitos dos fármacos
9.
J Biomol Struct Dyn ; 40(24): 13675-13681, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34693877

RESUMO

Heat shock protein 90 (Hsp90) is the prime molecular chaperone found to be overexpressed in cancer cells and pose as an anti-cancer therapeutic drug target for cancer chemotherapy. Even drugs are available which inhibit Hsp90, the associated side effects along with multi-drug regimen necessitate the identification of natural molecules to block the activity of Hsp90. In this present investigation, we performed virtual screening of Hsp90 inhibitors from a curated collection of natural molecules with proven pharmacological effects. This process helped in the identification of the top two scoring ligands, ginkgetin and theaflavin with favorable as well as crucial interactions with the Hsp90 ligand-binding pocket. Molecular dynamics simulations of these two natural molecules exhibited minimal fluctuations in the binding pattern of ginkgetin and theaflavin to Hsp90 which retained crucial contacts throughout the simulation time. We anticipate that ginkgetin and theaflavin could act as potent Hsp90 inhibitors which are under current investigation in our laboratory.Communicated by Ramaswamy H. Sarma.


Assuntos
Antineoplásicos , Biflavonoides , Proteínas de Choque Térmico HSP90 , Biflavonoides/farmacologia , Antineoplásicos/química , Simulação de Dinâmica Molecular
10.
J Biomol Struct Dyn ; 40(17): 7744-7761, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33749528

RESUMO

The viral particle, SARS-CoV-2 is responsible for causing the epidemic of Coronavirus disease 2019 (COVID-19). To combat this situation, numerous strategies are being thought for either creating its antidote, vaccine, or agents that can prevent its infection. For enabling research on these strategies, several target proteins are identified where, Spike (S) protein is of great potential. S-protein interacts with human angiotensin-converting-enzyme-2 (ACE2) for entering the cell. S-protein is a large protein and a portion of it designated as a receptor-binding domain (RBD) is the key region that interacts with ACE2, following to which the viral membrane fuses with the alveolar membrane to enter the human cell. The hypothesis is to identify molecules from the pool of anticancer phytochemicals as a lead possessing the ability to interact and mask the amino acids of RBD, making them unavailable to form associations with ACE2. Such a molecule is termed as 'fusion inhibitor'. We hypothesized to identify fusion inhibitors from the NPACT library of anticancer phytochemicals. For this, all the molecules from the NPACT were screened using molecular docking, the five top hits (Theaflavin, Ginkgetin, Ursolic acid, Silymarin and Spirosolane) were analyzed for essential Pharmacophore features and their ADMET profiles were studied following to which the best two hits were further analyzed for their interaction with RBD using Molecular Dynamics (MD) simulation. Binding free energy calculations were performed using MM/GBSA, proving these phytochemicals containing anticancer properties to serve as fusion inhibitors.Communicated by Ramaswamy H. Sarma.


Assuntos
Tratamento Farmacológico da COVID-19 , Silimarina , Aminoácidos/metabolismo , Enzima de Conversão de Angiotensina 2 , Angiotensinas/metabolismo , Antídotos , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Peptidil Dipeptidase A/química , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia , Ligação Proteica , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo
11.
Sci Rep ; 11(1): 20295, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645849

RESUMO

Novel SARS-CoV-2, an etiological factor of Coronavirus disease 2019 (COVID-19), poses a great challenge to the public health care system. Among other druggable targets of SARS-Cov-2, the main protease (Mpro) is regarded as a prominent enzyme target for drug developments owing to its crucial role in virus replication and transcription. We pursued a computational investigation to identify Mpro inhibitors from a compiled library of natural compounds with proven antiviral activities using a hierarchical workflow of molecular docking, ADMET assessment, dynamic simulations and binding free-energy calculations. Five natural compounds, Withanosides V and VI, Racemosides A and B, and Shatavarin IX, obtained better binding affinity and attained stable interactions with Mpro key pocket residues. These intermolecular key interactions were also retained profoundly in the simulation trajectory of 100 ns time scale indicating tight receptor binding. Free energy calculations prioritized Withanosides V and VI as the top candidates that can act as effective SARS-CoV-2 Mpro inhibitors.


Assuntos
Tratamento Farmacológico da COVID-19 , Proteases 3C de Coronavírus/metabolismo , Compostos Fitoquímicos/farmacologia , Antivirais/farmacologia , Biologia Computacional/métodos , Proteases 3C de Coronavírus/efeitos dos fármacos , Proteases 3C de Coronavírus/ultraestrutura , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Simulação de Acoplamento Molecular/métodos , Simulação de Dinâmica Molecular , Peptídeo Hidrolases/efeitos dos fármacos , Compostos Fitoquímicos/metabolismo , Inibidores de Proteases/farmacologia , Ligação Proteica/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/patogenicidade
12.
Ann Neurol ; 90(2): 193-202, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34184781

RESUMO

OBJECTIVE: This study was undertaken to identify susceptibility loci for cluster headache and obtain insights into relevant disease pathways. METHODS: We carried out a genome-wide association study, where 852 UK and 591 Swedish cluster headache cases were compared with 5,614 and 1,134 controls, respectively. Following quality control and imputation, single variant association testing was conducted using a logistic mixed model for each cohort. The 2 cohorts were subsequently combined in a merged analysis. Downstream analyses, such as gene-set enrichment, functional variant annotation, prediction and pathway analyses, were performed. RESULTS: Initial independent analysis identified 2 replicable cluster headache susceptibility loci on chromosome 2. A merged analysis identified an additional locus on chromosome 1 and confirmed a locus significant in the UK analysis on chromosome 6, which overlaps with a previously known migraine locus. The lead single nucleotide polymorphisms were rs113658130 (p = 1.92 × 10-17 , odds ratio [OR] = 1.51, 95% confidence interval [CI] = 1.37-1.66) and rs4519530 (p = 6.98 × 10-17 , OR = 1.47, 95% CI = 1.34-1.61) on chromosome 2, rs12121134 on chromosome 1 (p = 1.66 × 10-8 , OR = 1.36, 95% CI = 1.22-1.52), and rs11153082 (p = 1.85 × 10-8 , OR = 1.30, 95% CI = 1.19-1.42) on chromosome 6. Downstream analyses implicated immunological processes in the pathogenesis of cluster headache. INTERPRETATION: We identified and replicated several genome-wide significant associations supporting a genetic predisposition in cluster headache in a genome-wide association study involving 1,443 cases. Replication in larger independent cohorts combined with comprehensive phenotyping, in relation to, for example, treatment response and cluster headache subtypes, could provide unprecedented insights into genotype-phenotype correlations and the pathophysiological pathways underlying cluster headache. ANN NEUROL 2021;90:193-202.


Assuntos
Cefaleia Histamínica/epidemiologia , Cefaleia Histamínica/genética , Loci Gênicos/genética , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Estudos de Casos e Controles , Cefaleia Histamínica/diagnóstico , Estudos de Coortes , Feminino , Humanos , Masculino , Suécia/epidemiologia , Reino Unido/epidemiologia
13.
Mol Divers ; 25(1): 421-433, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32996011

RESUMO

The pandemic outbreak of the Corona viral infection has become a critical global health issue. Biophysical and structural evidence shows that spike protein possesses a high binding affinity towards host angiotensin-converting enzyme 2 and viral hemagglutinin-acetylesterase (HE) glycoprotein receptor. We selected HE as a target in this study to identify potential inhibitors using a combination of various computational approaches such as molecular docking, ADMET analysis, dynamics simulations and binding free energy calculations. Virtual screening of NPACT compounds identified 3,4,5-Trihydroxy-1,8-bis[(2R,3R)-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]benzo[7]annulen-6-one, Silymarin, Withanolide D, Spirosolane and Oridonin as potential HE inhibitors with better binding energy. Furthermore, molecular dynamics simulations for 100 ns time scale revealed that most of the key HE contacts were retained throughout the simulations trajectories. Binding free energy calculations using MM/PBSA approach ranked the top-five potential NPACT compounds which can act as effective HE inhibitors.


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Hemaglutininas Virais/metabolismo , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo , Proteínas Virais de Fusão/metabolismo , COVID-19/virologia , Humanos , Simulação de Acoplamento Molecular/métodos , Simulação de Dinâmica Molecular , Pandemias/prevenção & controle , Ligação Proteica
14.
Ann Clin Transl Neurol ; 7(9): 1716-1725, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32777174

RESUMO

Neuronal intranuclear inclusion disease (NIID) is a clinically heterogeneous neurodegenerative condition characterized by pathological intranuclear eosinophilic inclusions. A CGG repeat expansion in NOTCH2NLC was recently identified to be associated with NIID in patients of Japanese descent. We screened pathologically confirmed European NIID, cases of neurodegenerative disease with intranuclear inclusions and applied in silico-based screening using whole-genome sequencing data from 20 536 participants in the 100 000 Genomes Project. We identified a single European case harbouring the pathogenic repeat expansion with a distinct haplotype structure. Thus, we propose new diagnostic criteria as European NIID represents a distinct disease entity from East Asian cases.


Assuntos
Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/fisiopatologia , Receptor Notch2/genética , Adolescente , Adulto , Idade de Início , Europa (Continente) , Feminino , Humanos , Corpos de Inclusão Intranuclear/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Expansão das Repetições de Trinucleotídeos , População Branca , Sequenciamento Completo do Genoma
15.
J Clin Invest ; 130(11): 6080-6092, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32790644

RESUMO

No treatment for frontotemporal dementia (FTD), the second most common type of early-onset dementia, is available, but therapeutics are being investigated to target the 2 main proteins associated with FTD pathological subtypes: TDP-43 (FTLD-TDP) and tau (FTLD-tau). Testing potential therapies in clinical trials is hampered by our inability to distinguish between patients with FTLD-TDP and FTLD-tau. Therefore, we evaluated truncated stathmin-2 (STMN2) as a proxy of TDP-43 pathology, given the reports that TDP-43 dysfunction causes truncated STMN2 accumulation. Truncated STMN2 accumulated in human induced pluripotent stem cell-derived neurons depleted of TDP-43, but not in those with pathogenic TARDBP mutations in the absence of TDP-43 aggregation or loss of nuclear protein. In RNA-Seq analyses of human brain samples from the NYGC ALS cohort, truncated STMN2 RNA was confined to tissues and disease subtypes marked by TDP-43 inclusions. Last, we validated that truncated STMN2 RNA was elevated in the frontal cortex of a cohort of patients with FTLD-TDP but not in controls or patients with progressive supranuclear palsy, a type of FTLD-tau. Further, in patients with FTLD-TDP, we observed significant associations of truncated STMN2 RNA with phosphorylated TDP-43 levels and an earlier age of disease onset. Overall, our data uncovered truncated STMN2 as a marker for TDP-43 dysfunction in FTD.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Lobo Frontal/metabolismo , Demência Frontotemporal/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Estatmina/metabolismo , Biomarcadores/metabolismo , Proteínas de Ligação a DNA/genética , Feminino , Lobo Frontal/patologia , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Estatmina/genética
16.
Proteins ; 88(9): 1207-1225, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32323374

RESUMO

Receptor-based QSAR approaches can enumerate the energetic contributions of amino acid residues toward ligand binding only when experimental binding affinity is associated. The structural data of protein-ligand complexes are witnessing a tremendous growth in the Protein Data Bank deposited with a few entries on binding affinity. We present here a new approach to compute the Energetic CONTributions of Amino acid residues and its possible Cross-Talk (ECONTACT) to study ligand binding using per-residue energy decomposition, molecular dynamics simulations and rescoring method without the need for experimental binding affinity. This approach recognizes potential cross-talks among amino acid residues imparting a nonadditive effect to the binding affinity with evidence of correlative motions in the dynamics simulations. The protein-ligand interaction energies deduced from multiple structures are decomposed into per-residue energy terms, which are employed as variables to principal component analysis and generated cross-terms. Out of 16 cross-talks derived from eight datasets of protein-ligand systems, the ECONTACT approach is able to associate 10 potential cross-talks with site-directed mutagenesis, free energy, and dynamics simulations data strongly. We modeled these key determinants of ligand binding using joint probability density function (jPDF) to identify cross-talks in protein structures. The top two cross-talks identified by ECONTACT approach corroborated with the experimental findings. Furthermore, virtual screening exercise using ECONTACT models better discriminated known inhibitors from decoy molecules. This approach proposes the jPDF metric to estimate the probability of observing cross-talks in any protein-ligand complex. The source code and related resources to perform ECONTACT modeling is available freely at https://www.gujaratuniversity.ac.in/econtact/.


Assuntos
Enzimas/química , Escherichia coli/enzimologia , Mycobacterium tuberculosis/enzimologia , Software , Aminoácidos , Animais , Sítios de Ligação , Conjuntos de Dados como Assunto , Enzimas/genética , Enzimas/metabolismo , Escherichia coli/genética , Expressão Gênica , Humanos , Internet , Cinética , Ligantes , Camundongos , Simulação de Acoplamento Molecular , Mutação , Mycobacterium tuberculosis/genética , Análise de Componente Principal , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Especificidade por Substrato , Termodinâmica
17.
J Biomol Struct Dyn ; 38(13): 3838-3855, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31502527

RESUMO

Understanding the DNA-ligand interaction mechanism is of utmost importance to design selective inhibitors targeting the GC- and AT-rich DNA. This forms a primary strategy to block the association of transcription factors to promoters and subsequently, reduce the expression of genes. We present here an integrated approach combining various docking scoring functions, selective ligand-based pharmacophore models, molecular dynamics simulations and binding free energy calculations to prioritize natural compounds specific to GC minor groove binding. The approach initially applies a selective ligand-based pharmacophore model built upon known GC minor groove binders to identify potential GC minor groove binders from natural compound repositories. These GC minor groove binders were then cross-examined with selective pharmacophore models (controls) based on AT-rich binders and GC intercalators to assess its unfitness. This approach involves the calculation of binding energies of known GC- and AT minor groove binders using three scoring functions without any constraint on groove specificity of GC- and AT-rich DNA. The evaluation of empirical scoring functions led to enumeration of a new parameter, the energy difference computed using Glide (sensitivity = 80%) to recognize GC-rich binders effectively. Molecular dynamics simulations and binding free energy calculations (MM/GBSA) constituted the final phase of this approach to analyze the interactions of natural molecules (hits) with GC-rich DNA comprehensively. Seven natural molecules were selected which exhibited fewer fluctuations in RMSD and RMSF profiles and better GC-rich DNA binding with low free energies of binding. These natural hits prioritized by this integrated approach can be tested in DNA binding assay.Communicated by Ramaswamy H. Sarma.


Assuntos
DNA , Simulação de Dinâmica Molecular , Ligantes , Simulação de Acoplamento Molecular
18.
Toxicol Mech Methods ; 30(3): 159-166, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31618094

RESUMO

The assessment of major organ toxicities through in silico predictive models plays a crucial role in drug discovery. Computational tools can predict chemical toxicities using the knowledge gained from experimental studies which drastically reduces the attrition rate of compounds during drug discovery and developmental stages. The purpose of in silico predictions for drug leads and anticipating toxicological endpoints of absorption, distribution, metabolism, excretion and toxicity, clinical adverse impacts and metabolism of pharmaceutically active substances has gained widespread acceptance in academia and pharmaceutical industries. With unrestricted accessibility to powerful biomarkers, researchers have an opportunity to contemplate the most accurate predictive scores to evaluate drug's adverse impact on various organs.A multiparametric model involving physico-chemical properties, quantitative structure-activity relationship predictions and docking score was found to be a more reliable predictor for estimating chemical toxicities with potential to reflect atomic-level insights. These in silico models provide informed decisions to carry out in vitro and in vivo studies and subsequently confirms the molecules clues deciphering the cytotoxicity, pharmacokinetics, and pharmacodynamics and organ toxicity properties of compounds. Even though the drugs withdrawn by USFDA at later phases of drug discovery which should have passed all the state-of-the-art experimental approaches and currently acceptable toxicity filters, there is a dire need to interconnect all these molecular key properties to enhance our knowledge and guide in the identification of leads to drug optimization phases. Current computational tools can predict ADMET and organ toxicities based on pharmacophore fingerprint, toxicophores and advanced machine-learning techniques.


Assuntos
Descoberta de Drogas , Testes de Toxicidade/métodos , Animais , Humanos , Modelos Estatísticos , Especificidade de Órgãos , Relação Quantitativa Estrutura-Atividade
19.
J Recept Signal Transduct Res ; 39(3): 226-234, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31509043

RESUMO

Cardiotonic steroids (CTS) are steroidal drugs, processed from the seeds and dried leaves of the genus Digitalis as well as from the skin and parotid gland of amphibians. The most commonly known CTS are ouabain, digoxin, digoxigenin and bufalin. CTS can be used for safer medication of congestive heart failure and other related conditions due to promising pharmacological and medicinal properties. Ouabain isolated from plants is widely utilized in in vitro studies to specifically block the sodium potassium (Na+/K+-ATPase) pump. For checking, whether ouabain derivatives are robust inhibitors of Na+/K+-ATPase pump, molecular docking simulation was performed between ouabain and its derivatives using YASARA software. The docking energy falls within the range of 8.470 kcal/mol to 7.234 kcal/mol, in which digoxigenin was found to be the potential ligand with the best docking energy of 8.470 kcal/mol. Furthermore, pharmacophore modeling was applied to decipher the electronic features of CTS. Molecular dynamics simulation was also employed to determine the conformational properties of Na+/K+-ATPase-ouabain and Na+/K+-ATPase-digoxigenin complexes with the plausible structural integrity through conformational ensembles for 100 ns which promoted digoxigenin as the most promising CTS for treating conditions of congestive heart failure patients.


Assuntos
Glicosídeos Cardíacos/farmacologia , Simulação de Acoplamento Molecular , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Difusão , Digoxina/química , Digoxina/farmacologia , Ligação de Hidrogênio , Ligantes , Modelos Biológicos , Ouabaína/química , Ouabaína/farmacologia , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes , ATPase Trocadora de Sódio-Potássio/metabolismo
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