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1.
Nat Immunol ; 14(3): 281-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23334788

RESUMO

TCRαß thymocytes differentiate into either CD8αß(+) cytotoxic T lymphocytes or CD4(+) helper T cells. This functional dichotomy is controlled by key transcription factors, including the helper T cell master regulator ThPOK, which suppresses the cytolytic program in major histocompatibility complex (MHC) class II-restricted CD4(+) thymocytes. ThPOK continues to repress genes of the CD8 lineage in mature CD4(+) T cells, even as they differentiate into effector helper T cell subsets. Here we found that the helper T cell fate was not fixed and that mature, antigen-stimulated CD4(+) T cells terminated expression of the gene encoding ThPOK and reactivated genes of the CD8 lineage. This unexpected plasticity resulted in the post-thymic termination of the helper T cell program and the functional differentiation of distinct MHC class II-restricted CD4(+) cytotoxic T lymphocytes.


Assuntos
Linfócitos T Citotóxicos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular , Linhagem da Célula , Citrobacter rodentium/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Proteínas de Homeodomínio/genética , Interleucina-7/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/metabolismo , Timócitos/metabolismo
2.
Toxicol Appl Pharmacol ; 487: 116978, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795847

RESUMO

Non-small cell lung cancer (NSCLC) is a complex malignancy with a high degree of heterogeneity, representing approximately 85% of all lung cancer cases. The treatment landscape for NSCLC has been revolutionised by incorporating targeted and immunotherapies; however, novel therapeutic modalities are consistently needed to enhance the treatment outcomes. Indeed, alternative anti-cancer therapies involving natural products have drawn the attention of clinicians and scientists owing to their remarkable chemopreventive potential, often displaying minimal toxicity. D-carvone (CN) is one such natural product that has exhibited numerous promising therapeutic benefits, yet its efficacy against NSCLC remains enigmatic. In the present study, network pharmacological studies and molecular docking in conjunction with in-vitro validation were used to elucidate the underlying mechanism of action of CN comprehensively. Different databases revealed a total of 77 putative anti-NSCLC targets of CN. The identified core targets were utilised to construct a "Compound- Target- Disease" network by Cytoscape (v3.9.0). Further analysis identified 5 core/ hub targets of CN including JAK2, ERK1, ESR1, GSK3B and HSP90AA1. Molecular docking indicated a strong binding interaction of the compound with these core targets. Also, Gene Ontology and KEGG analysis validated the involvement of multiple biological processes. Additionally, CN significantly inhibited cell proliferation, clonogenicity, and wound healing potential while promoting apoptosis in a dose-dependent manner in H1299 and A549 cell lines as examined by flow cytometry, morphological assessment, and western blotting. In conclusion, this study delineates the therapeutic effects of CN on NSCLC, thus highlighting CN as a putative drug candidate for further analysis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Monoterpenos Cicloexânicos , Neoplasias Pulmonares , Simulação de Acoplamento Molecular , Farmacologia em Rede , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Monoterpenos Cicloexânicos/farmacologia , Células A549 , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Mapas de Interação de Proteínas , Apoptose/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química
3.
Mol Pharm ; 21(2): 535-549, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38271213

RESUMO

We report an efficient sustainable two-step anion exchange synthetic procedure for the preparation of choline API ionic liquids (Cho-API-ILs) that contain active pharmaceutical ingredients (APIs) as anions combined with choline-based cations. We have evaluated the in vitro cytotoxicity for the synthesized compounds using three different cells lines, namely, HEK293 (normal kidney cell line), SW480, and HCT 116 (colon carcinoma cells). The solubility of APIs and Cho-API-ILs was evaluated in water/buffer solutions and was found higher for Cho-API-ILs. Further, we have investigated the antimicrobial potential of the pure APIs, ILs, and Cho-API-ILs against clinically relevant microorganisms, and the results demonstrated the promise of Cho-API-ILs as potent antimicrobial agents to treat bacterial infections. Moreover, the aggregation and adsorption properties of the Cho-API-ILs were observed by using a surface tension technique. The aggregation behavior of these Cho-API-ILs was further supported by conductivity and pyrene probe fluorescence. The thermodynamics of aggregation for Cho-API-ILs has been assessed from the temperature dependence of surface tension. The micellar size and their stability have been studied by dynamic light scattering, transmission electron microscopy, and zeta potential. Therefore, the duality in the nature of Cho-API-ILs has been explored with the upgradation of their physical, chemical, and biopharmaceutical properties, which enhance the opportunities for advances in pharmaceutical sciences.


Assuntos
Anti-Infecciosos , Líquidos Iônicos , Humanos , Solubilidade , Líquidos Iônicos/química , Células HEK293 , Micelas , Colina/química
4.
Pediatr Surg Int ; 40(1): 57, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353772

RESUMO

PURPOSE: Wilms' tumor (WT) is a rare kidney cancer that primarily affects children. Exosomes are extracellular vesicles that cargo nucleic acids, proteins,etc. for cellular communication. Long non-coding RNAs (lncRNAs) have utility as biomarkers for cancer diagnosis, prognosis, and disease monitoring. We hypothesize that expression of lncRNA, metastasis-associated lung adenocarcinoma transcript-1(MALAT1), is dysregulated and possibly trafficked within exosomes to influence the tissue microenvironment for metastasis and recurrence of WT. METHODS: We investigated the expression of MALAT1 in thirty WT samples by qPCR. Exosomes were isolated using a precipitated and affinity-binding-based kit, and characterized using TEM, NTA, and DLS. RESULTS: Mean number of exosomes was 9.01×108/mL in primary culture, 1.64×108/mL in urine, and 4.65×108/plasma:400µl. Average yield of total RNA was 1.28µg (primary-culture supernatant:1ml), 1.47µg (Urine:1ml), 1.65µg (Plasma:400 µL). We quantified MALAT1 in exosomes derived from these sources in patients of WT. Expression of MALAT1 was significantly downregulated (p=0.008) in WT samples. CONCLUSION: This is the first study that demonstrated the presence of lncRNA MALAT1 in various invasive and non-invasive samples of patients with WT(primary tissue culture, urine, and plasma samples).


Assuntos
Exossomos , Neoplasias Renais , RNA Longo não Codificante , Tumor de Wilms , Criança , Humanos , RNA Longo não Codificante/genética , Tumor de Wilms/genética , Neoplasias Renais/genética , Biópsia Líquida , Exossomos/genética , Microambiente Tumoral
5.
J Cell Biochem ; 123(2): 259-274, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34636440

RESUMO

The treatments available for non-small cell lung cancer exert various side effects in patients, and the burden of treatment cost is high. Therefore, exploring the alternative system of medicines, including therapies based on natural compounds, has become inevitable in developing anticancer therapeutics. This study used an integrated approach involving in-silico and in-vitro methods to explore natural compounds targeting Bax and Bcl2 for their apoptotic potential. Molecular docking followed by molecular dynamics (MD) simulation of thymoquinone (Tq) and quercetin (Qu) with Bax and Bcl2 were carried out to explore their interactions and stability under explicit solvent conditions. Tq and Qu showed appreciable binding affinities toward Bax (-6.2 and -7.1 kcal/mol, respectively) and Bcl2 (-5.6 and -6.4 kcal/mol, respectively) with well-organized conformational fitting compatibility. The MD simulation results revealed the development of stable complexes maintained by various noncovalent interactions that were preserved throughout the 100 ns trajectories. Further studies with these compounds were carried out using various in-vitro experimental approaches like MTT assay, apoptotic assay, and Western blot. IC50 values of Tq and Qu alone in A549 cells were found to be 45.78 and 35.69 µM, while in combination, it comes down to 22.49 µM, which is quite impressive. Similarly, in apoptosis assay, a combination of Tq and Qu shows 50.9% early apoptosis compared to Tq (40.6%) and Qu (33.3%) when taken alone. These assays signify their apoptotic induction potential, whereas both compounds significantly reduce the expression of antiapoptotic protein Bcl2 and induce proapoptotic Bax, suggestive of sensitizing NSCLS cells toward apoptosis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo , Células A549 , Benzoquinonas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Quercetina/farmacologia
6.
Toxicol Appl Pharmacol ; 417: 115467, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33631231

RESUMO

Owing to the technological advancements, including next generation sequencing, the significance of deregulated epigenetic mechanisms in cancer initiation, progression and treatment has become evident. The accumulating knowledge relating to the epigenetic markers viz. DNA methylation, Histone modifications and non-coding RNAs make them one of the most interesting candidates for developing anti-cancer therapies. The reversibility of deregulated epigenetic mechanisms through environmental and dietary factors opens numerous avenues in the field of chemoprevention and drug development. Recent studies have proven that plant-derived natural products encompass a great potential in targeting epigenetic signatures in cancer and numerous natural products are being explored for their possibility to be considered as "epi-drug". This review intends to highlight the major aberrant epigenetic mechanisms and summarizes the essential functions of natural products like Resveratrol, Quercetin, Genistein, EGCG, Curcumin, Sulforaphane, Apigenin, Parthenolide and Berberine in modulating these aberrations. This knowledge along with the challenges and limitations in this field has potential and wider implications in developing novel and successful therapeutic strategies. The increased focus in the area will possibly provide a better understanding for the development of dietary supplements and/or drugs either alone or in combination. The interaction of epigenetics with different hallmarks of cancer and how natural products can be utilized to target them will also be interesting in the future therapeutic approaches.


Assuntos
Anticarcinógenos/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Reprogramação Celular/efeitos dos fármacos , Dieta , Epigênese Genética/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Animais , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/genética , Neoplasias/patologia
7.
Mol Pharm ; 15(9): 4173-4189, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30040903

RESUMO

Apoptotic evasion by cancerous cells being one of the striking hallmarks of cancer has turned into a new arena of drug discovery. A large number of pathways reported that govern the apoptotic evasion have been reported. Fas-activated serine/threonine kinase (FASTK) is a member of Ser/Thr kinase family, and it has been implicated in the apoptotic evasion and, hence, the development of cancer. Keeping this in view, a series of novel thienopyrimidine-based chalcones have been synthesized and evaluated to modulate the FASTK mediated apoptotic evasion. Initial screening was done by enzyme inhibition assay and binding studies, which showed that out of 15 synthesized compounds, 3 thienopyrimidine-based chalcone derivatives possess considerably high binding affinity and enzyme inhibitory potential (nM range) for FASTK. Cell proliferation assessment of selected compounds was performed on HEK-293 and MCF-7 cells. For MCF-7 cells, compounds 2, 10, and 12 show IC50 values of 20.22 ± 1.50, 6.52 ± 0.82, and 8.20 ± 0.61 µM, respectively. Annexin-V and PI staining suggested that these molecules induce apoptosis in MCF-7 cells, arrest the cell cycle in the G0/G1 phase, and subsequently inhibit cell migration presumably by inhibiting FASTK and reactive oxygen species production. In conclusion, we have successfully designed, synthesized, and characterized thienopyrimidine-based chalcones that inhibit FASTK and induce apoptosis. These compounds may be exploited as potential anticancer agents.


Assuntos
Proliferação de Células/efeitos dos fármacos , Chalconas/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirimidinas/farmacologia , Apoptose/efeitos dos fármacos , Calorimetria , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Chalconas/química , Células HEK293 , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Pirimidinas/química , Espécies Reativas de Oxigênio/metabolismo
8.
Virus Genes ; 54(5): 647-661, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30022343

RESUMO

It is important to study the molecular properties of vertically transmitted viruses in early infancy to understand disease progression. P24 having an important role in virus assembly and maturation was selected to explore the genotypic characteristics. Blood samples, obtained from 82 HIV-1 positive infants, were categorized into acute (≤ 6 months) and early (> 6-18 months) age groups. Of the 82 samples, 79 gave amplification results for p24, which were then sequenced and analysed. Amino acid heterogeneity analysis showed that substitutions were more frequent. Several substitution mutations were present in some of the sequences of both the age groups in the functional motifs of the gene namely Beta hairpin, CyPA binding loop, residues L136 and L190, linker region and major homology region. In the acute age group, an insertion of Asparagine residue (N5NL6) was observed in the ß hairpin region in one of the sequences. This insertion was accompanied with analogous substitutions of N5Q, Q7L and G8R. In the early age group, a deletion of two residues; VK181-182, was observed at the C-terminal end in one of the sequences. These mutations may impair the structure of the protein leading to defective virus assembly. Protein variation effect analyzer software showed that deleterious mutations were more in the acute than the early age group. Variability analysis revealed that the amino acid heterogeneity was comparatively higher in the acute than the early age group. Variability in the virus was decreasing with the increasing age of the infants indicating that the virus is gradually evolving under positive selection pressure. HLA class 1 binding peptide analysis showed that the epitopes TPQDLNTML and RMYSPVSIL may be helpful in designing epitope based vaccine.


Assuntos
Variação Genética , Proteína do Núcleo p24 do HIV/genética , Infecções por HIV/virologia , HIV-1/genética , Motivos de Aminoácidos , Evolução Molecular , Genes Virais , Proteína do Núcleo p24 do HIV/química , Proteína do Núcleo p24 do HIV/metabolismo , HIV-1/classificação , Antígenos HLA/metabolismo , Humanos , Lactente , Reação em Cadeia da Polimerase , Análise de Sequência de Proteína
9.
Brief Bioinform ; 16(4): 675-99, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25256288

RESUMO

Dysregulation or inhibition of apoptosis favors cancer and many other diseases. Understanding of the network interaction of the genes involved in apoptotic pathway, therefore, is essential, to look for targets of therapeutic intervention. Here we used the network theory methods, using experimentally validated 25 apoptosis regulatory proteins and identified important genes for apoptosis regulation, which demonstrated a hierarchical scale-free fractal protein-protein interaction network. TP53, BRCA1, UBIQ and CASP3 were recognized as a four key regulators. BRCA1 and UBIQ were also individually found to control highly clustered modules and play an important role in the stability of the overall network. The connection among the BRCA1, UBIQ and TP53 proteins was found to be important for regulation, which controlled their own respective communities and the overall network topology. The feedback loop regulation motif was identified among NPM1, BRCA1 and TP53, and these crucial motif topologies were also reflected in high frequency. The propagation of the perturbed signal from hubs was found to be active upto some distance, after which propagation started decreasing and TP53 was the most efficient signal propagator. From the functional enrichment analysis, most of the apoptosis regulatory genes associated with cardiovascular diseases and highly expressed in brain tissues were identified. Apart from TP53, BRCA1 was observed to regulate apoptosis by influencing motif, propagation of signals and module regulation, reflecting their biological significance. In future, biochemical investigation of the observed hub-interacting partners could provide further understanding about their role in the pathophysiology of cancer.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Fractais , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/fisiologia , Ligação Proteica
10.
Am J Pathol ; 186(2): 347-58, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26683666

RESUMO

Dysregulated growth and loss of podocytes are important features of HIV-associated nephropathy. Recently, HIV was reported to induce a new type of programed cell death, pyroptosis, in T lymphocytes through induction of Nod-like receptor protein 3 (NLRP3) inflammasome complexes. We evaluated the role of HIV in podocyte NLRP3 inflammasome formation both in vivo and in vitro. Renal cortical sections of HIV-transgenic mice (Tg26) displayed increased expression of NLRP3, ASC (a CARD protein), caspase-1, and IL-1ß proteins, confirming NLRP3 inflammasome complex formation in podocytes of Tg26 mice. Renal tissues of Tg26 mice also displayed enhanced mRNA levels and protein expressions of inflammasome markers (NLRP3, ASC, and caspase-1, and IL-1ß). Serum of Tg26 mice also showed elevated concentrations of IL-1ß cytokine compared with FVBN mice. HIV induced pyroptosis in a dose- and time-dependent manner within podocytes, a phenotype of inflammasome activation. Caspase-1 inhibitor not only attenuated podocyte expression of caspase-1 and IL-1ß but also provided protection against pyroptosis, suggesting that HIV-induced podocyte injury was mediated by caspase-1 activation. Interestingly, HIV-induced podocyte pyroptosis could be partially inhibited by Tempol (a superoxide dismutase-mimetic agent) and by glyburide (an inhibitor of potassium efflux). These findings suggest that generation of reactive oxygen species and potassium efflux contribute to HIV-induced pyroptosis and NLRP3 inflammasome activation in podocytes.


Assuntos
Nefropatia Associada a AIDS/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Transporte/metabolismo , Inflamassomos/metabolismo , Podócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose/fisiologia , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Podócitos/virologia
11.
J Med Virol ; 89(9): 1606-1619, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28370302

RESUMO

Targeting properties of vertically transmitted viruses in early infancy is important to understand disease progression. To investigate genotypic characteristics of transmitted viruses, blood samples were obtained from infants aged 6 weeks-18 months, categorized in two age groups, acute (<6 months) and early (>6-18 months). Nef having an important role in pathogenesis was selected to explore the viral characteristics. A total of 57 PCR positive samples, amplified by nef gene were sequenced. Analysis showed that 50 sequences belonged to subtype C. In one sequence of acute age group, a long insertion of 10 residues (AAERMRRAEP) in variable region and a 13 residues deletion (ATNNADCAWLEAQ) around proteolytic cleavage region of gene in another sequence was observed. Insertions were also observed in sequences of early age group, however, they ranged from two to eight residues only. In one sequence of early age group, 3/4 arginines at positions 19, 21, 22 of arginine cluster were mutated to glutamine, alanine, and glutamine, respectively. Entropy analysis of two age groups revealed presence of several residues with statistically significant differences in their variability. Among these, 15 (R18,R23,R24; A66,L68,Q71; E74,E77,E78; V87,M92; R119, P144, E167, and C176) belonged to functional motifs, out of which, 12 were in acute age group, suggesting that variability was greater in this group. Prediction of HLA binding peptide motif revealed that epitope LTFGWCFKL was present in >80% study sequences. This epitope was also present in maximum number of HLA types circulating in India and vaccine candidate sequences, suggesting that it may be helpful in designing an epitope-based vaccine.


Assuntos
Variação Genética , Infecções por HIV/virologia , HIV-1/genética , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética , Sangue/virologia , Epitopos de Linfócito T/genética , Genótipo , Humanos , Índia , Lactente , Mutação , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Produtos do Gene nef do Vírus da Imunodeficiência Humana/classificação
12.
Semin Immunol ; 25(4): 273-81, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24246226

RESUMO

During thymic development, thymocytes expressing a T cell receptor consisting of an alpha and beta chain (TCRαß), commit to either the cytotoxic- or T helper-lineage fate. This lineage dichotomy is controlled by key transcription factors, including the T helper (Th) lineage master regulator, the Th-inducing BTB/POZ domain-containing Kruppel-like zinc-finger transcription factor, ThPOK, (formally cKrox or Zfp67; encoded by Zbtb7b), which suppresses the cytolytic program in major histocompatibility complex (MHC) class II-restricted CD4(+) thymocytes and the Runt related transcription factor 3 (Runx3), which counteracts ThPOK in MHC class I restricted precursor cells and promotes the lineage commitment of CD8αß(+) cytolytic T lymphocytes (CTL). ThPOK continues to repress the CTL gene program in mature CD4(+) T cells, even as they differentiate into effector Th cell subsets. The Th cell fate however is not fixed and two recent studies showed that mature, antigen-stimulated CD4(+) T cells have the flexibility to terminate the expression of ThPOK and functionally reprogram to cytotoxic effector cells. This unexpected plasticity of CD4(+) T cells results in the post-thymic termination of the Th lineage fate and the functional differentiation of distinct MHC class II-restricted CD4(+) CTL. The recognition of CD4 CTL as a defined separate subset of effector cells and the identification of the mechanisms and factors that drive their reprogramming finally create new opportunities to explore the physiological relevance of these effector cells in vivo and to determine their pivotal roles in both, protective immunity as well as in immune-related pathology.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Citotoxicidade Imunológica , Subpopulações de Linfócitos T/imunologia , Animais , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Regulação da Expressão Gênica , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Ativação Linfocitária/imunologia , Tecido Linfoide/imunologia , Tecido Linfoide/metabolismo , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Timo/imunologia , Timo/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica
13.
Arch Virol ; 161(5): 1101-13, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26801790

RESUMO

Drug resistance mutations in the Pol gene of human immunodeficiency virus 1 (HIV-1) are one of the critical factors associated with antiretroviral therapy (ART) failure in HIV-1 patients. The issue of resistance to reverse transcriptase inhibitors (RTIs) in HIV infection has not been adequately addressed in the Indian subcontinent. We compared HIV-1 reverse transcriptase (RT) gene sequences to identify mutations present in HIV-1 patients who were ART non-responders, ART responders and drug naive. Genotypic drug resistance testing was performed by sequencing a 655-bp region of the RT gene from 102 HIV-1 patients, consisting of 30 ART-non-responding, 35 ART-responding and 37 drug-naive patients. The Stanford HIV Resistance Database (HIVDBv 6.2), IAS-USA mutation list, ANRS_09/2012 algorithm, and Rega v8.02 algorithm were used to interpret the pattern of drug resistance. The majority of the sequences (96 %) belonged to subtype C, and a few of them (3.9 %) to subtype A1. The frequency of drug resistance mutations observed in ART-non-responding, ART-responding and drug-naive patients was 40.1 %, 10.7 % and 20.58 %, respectively. It was observed that in non-responders, multiple mutations were present in the same patient, while in responders, a single mutation was found. Some of the drug-naive patients had more than one mutation. Thymidine analogue mutations (TAMs), however, were found in non-responders and naive patients but not in responders. Although drug resistance mutations were widely distributed among ART non-responders, the presence of resistance mutations in the viruses of drug-naive patients poses a big concern in the absence of a genotyping resistance test.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Transcriptase Reversa do HIV/genética , HIV-1/efeitos dos fármacos , Adulto , Idoso , Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral/genética , Feminino , Infecções por HIV/virologia , Transcriptase Reversa do HIV/efeitos dos fármacos , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Filogenia , Análise de Sequência de DNA , Falha de Tratamento , Adulto Jovem
14.
Am J Physiol Renal Physiol ; 309(3): F189-203, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26084932

RESUMO

ANG II type 1 receptor blockade (AT1R-BLK) is used extensively to slow down the progression of proteinuric kidney diseases. We hypothesized that AT1R-BLK provides podocyte protection through regulation of silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) and vitamin D receptor (VDR) expression under adverse milieus such as high glucose and human immunodeficiency virus infection. Both AT1R-BLK and VDR agonists (VDAs) stimulated VDR complex formation that differed not only in their composition but also in their functionality. AT1R-BLK-induced VDR complexes contained predominantly unliganded VDR, SMRT, and phosphorylated histone deacetylase 3, whereas VDA-VDR complexes were constituted by liganded VDR and CREB-binding protein/p300. AT1R-BLK-induced complexes attenuated podocyte acetyl-histone 3 levels as well as cytochrome P-450 family 24A1 expression, thus indicating their deacetylating and repressive properties. On the other hand, VDA-VDR complexes not only increased podocyte acetyl-histone 3 levels but also enhanced cytochrome P-450 family 24A1 expression, thus suggesting their acetylating and gene activation properties. AT1R-BLK- induced podocyte SMRT inhibited expression of the proapoptotic gene BAX through downregulation of Wip1 and phosphorylation of checkpoint kinase 2 in high-glucose milieu. Since SMRT-depleted podocytes lacked AT1R-BLK-mediated protection against DNA damage, it appears that SMRT is necessary for DNA repairs during AT1R-BLK. We conclude that AT1R-BLK provides podocyte protection in adverse milieus predominantly through SMRT expression and partly through unliganded VDR expression in 1,25(OH)2D-deficient states; on the other hand, AT1R-BLK contributes to liganded VDR expression in 1,25(OH)2D-sufficient states.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Correpressor 2 de Receptor Nuclear/fisiologia , Acetilação , Proteínas Reguladoras de Apoptose/biossíntese , Proteínas Correpressoras/efeitos dos fármacos , Dano ao DNA , Relação Dose-Resposta a Droga , Histonas/metabolismo , Humanos , Losartan/farmacologia , Podócitos/efeitos dos fármacos , Podócitos/enzimologia , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Receptores de Calcitriol/efeitos dos fármacos , Vitamina D3 24-Hidroxilase/biossíntese , Vitamina D3 24-Hidroxilase/metabolismo
15.
Cancer Metastasis Rev ; 32(1-2): 229-68, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23114844

RESUMO

Hepatocellular carcinoma (HCC) is one of the most lethal and prevalent cancers in many developing countries including India. Among the various etiological factors being implicated in the cause of HCC, the most important cause, however, is hepatitis B virus (HBV) infection. Among all HBV genes, HBx is the most critical carcinogenic component, the molecular mechanisms of which have not been completely elucidated. Despite its clinical significance, there exists a very elemental understanding of the molecular, cellular, and environmental mechanisms that drive disease pathogenesis in HCC infected with HBV. Furthermore, there are only limited therapeutic options, the clinical benefits of which are insignificant. Therefore, the quest for novel and effective therapeutic regimen against HBV-related HCC is of paramount importance. This review attempts to epitomize the current state of knowledge of this most common and dreaded liver neoplasm, highlighting the putative treatment avenues and therapeutic research strategies that need to be implemented with immediate effect for tackling HBV-related HCC that has plagued the medical and scientific fraternity for decades. Additionally, this review proposes a novel "five-point" management algorithm for HBV-related HCC apart from portraying the unmet needs, principal challenges, and scientific perspectives that are relevant to controlling this accelerating global health crisis.


Assuntos
Carcinoma Hepatocelular/etiologia , Vírus da Hepatite B , Hepatite B/complicações , Neoplasias Hepáticas/etiologia , Animais , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/terapia , Modelos Animais de Doenças , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/terapia , Terapia de Alvo Molecular , Metástase Neoplásica
16.
Arch Virol ; 159(9): 2303-20, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24748005

RESUMO

Genetic heterogeneity in the nef genes from human immunodeficiency virus type 1 (HIV-1)-infected rapid progressors (RPs) and long-term nonprogressors (LTNPs) was analyzed to identify various amino acid substitutions responsible for the discernible difference in disease progression. It was found that the majority of the strains characterized belonged to subtype C, followed by several BC recombinants and subtype A1. Complete nef subtype C sequences from 33 RPs and seven LTNPs were compared, and it was observed that, in the majority of the sequences from both groups, highly conserved functional motifs showed subtle changes. However, drastic changes were observed in two isolates from LTNPs where the arginine cluster was deleted, while in one of them, additionally, acidic residues were replaced by basic residues (EEEEE→RK(R)KKE). The deletion of the arginine cluster and the mutation of acidic residues to basic residues are predicted to delay disease development by abolishing CD4 downmodulation and causing diminution of major histocompatibility complex class I (MHC-I) downregulation, respectively. Nonetheless, this is an exclusive finding in these LTNPs, which necessitates their analysis at the functional level. The synonymous-to-nonsynonymous substitution ratio was greater than one in both of the groups, suggesting amino acid sequence conservation and functional robustness. Interpatient nucleotide distance within the group and between the two groups showed very little variation, confirming genetic relatedness among isolates.


Assuntos
Síndrome da Imunodeficiência Adquirida/patologia , Síndrome da Imunodeficiência Adquirida/virologia , Variação Genética , HIV-1/genética , Mutação , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética , Adulto , Feminino , Sobreviventes de Longo Prazo ao HIV , HIV-1/imunologia , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Análise de Sequência de DNA , Adulto Jovem , Produtos do Gene nef do Vírus da Imunodeficiência Humana/metabolismo
17.
Exp Cell Res ; 319(13): 2073-2080, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23611955

RESUMO

Recent studies suggested that miRNAs are involved in the development of the pathogenesis of HIV-associated nephropathy (HIVAN). Rapamycin, a widely used mTOR inhibitor, has been demonstrated to slow down the progression of HIVAN. However, the role of miRNA in the regulation of these processes has not been investigated so far. In the current study, we have used a microarray-based approach in combination with real-time PCR to profile the miRNA expression patterns in rapamycin-treated HIVAN mice (Tg26). Our results demonstrated that 19 miRNAs belonging to 13 different families expressed differentially in renal tissues of rapamycin-receiving Tg26 mice when compared to Tg26 mice-receiving saline only. The patterns of miRNAs expression in rapamycin-receiving Tg26 mice took a reverse turn. These miRNAs were classified into 8 functional categories. In in vitro studies, we examined the expression of specific miRNAs in HIV-1 transduced human podocytes (HIV/HPs). HIV/HPs displayed attenuation of expression of miR-99a, -100a, -199a and miR-200, whereas, rapamycin inhibited this effect of HIV. These findings suggest that rapamycin-mediated up-regulation of specific miRNAs could contribute to amelioration of renal lesions in HIVAN mice.


Assuntos
Nefropatia Associada a AIDS/genética , MicroRNAs/genética , Sirolimo/farmacologia , Nefropatia Associada a AIDS/patologia , Nefropatia Associada a AIDS/prevenção & controle , Animais , Células Cultivadas , Progressão da Doença , Avaliação Pré-Clínica de Medicamentos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , HIV-1/fisiologia , Células HeLa , Humanos , Imunossupressores/farmacologia , Masculino , Camundongos , Camundongos Transgênicos
18.
Food Nutr Bull ; 35(2): 277-85, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25076775

RESUMO

BACKGROUND: To achieve the United Nations Millennium Development Goals, particularly reduction in child mortality (Millennium Development Goal 4), effective interventions to address severe and moderate acute malnutrition (SAM and MAM) among children under 5 years of age must be implemented and brought to scale alongside preventive measures. Bangladesh has an estimated 600,000 children with SAM, for a prevalence of 4%, while 1.8 million children suffer from MAM. OBJECTIVE: To assess the feasibility and constraints of community-based management of acute malnutrition (CMAM), a relatively new approach, in managing SAM and MAM among children in Bangladesh. METHODS: The methodology involved desk reviews of documents by searching through PubMed and other databases for published literature on CMAM in Bangladesh. We also did a hand search of policy and program documents, including the draft National Nutrition Policy 2013; the Health, Nutrition, Population Sector Development Program document of the Ministry of Health and Family Welfare, Government of Bangladesh; the Sixth Five Year Plan; and the Operational Plans of the National Nutrition Services of Bangladesh. RESULTS: . The conventional approach in Bangladesh has been to treat children suffering from SAM and associated complications in hospital settings. There is no program to take care of children with MAM. There is a dearth of local evidence to operationalize and implement CMAM in the context of Bangladesh. This paper summarizes the scientific literature and rationale for the implementation of CMAM in Bangladesh. It also provides recommendations to improve health strategies related to CMAM, discusses diets being developed that may result in better implementation of CMAM, and offers recommendations for areas of additional necessary research. CONCLUSIONS: A recommended approach for Bangladesh on the management of acute malnutrition would be to integrate CMAM into the rollout of the National Nutrition Services so that screening, identification, referral, and treatment of acutely malnourished children could be effectively managed within the community-based health service delivery system. Given that the vast majority of children are suffering from MAM and could be treated with locally developed food supplements, a significant emphasis of the CMAM approach in Bangladesh should be to screen and treat MAM. Over time, this would also result in fewer SAM cases. However, even with this approach, there would still be a small number of children who have SAM and who ideally should be treated with specialized therapeutic foods. While the Government of Bangladesh is awaiting full-scale production of a local ready-to-use therapeutic food (RUTF), an interim strategy is needed to effectively treat these severely wasted children on an outpatient basis.


Assuntos
Serviços de Saúde Comunitária , Desnutrição/terapia , Doença Aguda , Bangladesh , Pré-Escolar , Serviços de Saúde Comunitária/economia , Custos e Análise de Custo , Comportamentos Relacionados com a Saúde , Implementação de Plano de Saúde , Política de Saúde , Recursos em Saúde/economia , Recursos em Saúde/organização & administração , Financiamento da Assistência à Saúde , Humanos , Lactente , Desnutrição/prevenção & controle , Política Nutricional , Nações Unidas
19.
PLOS Glob Public Health ; 4(2): e0002596, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422092

RESUMO

Tuberculosis (TB) and non-communicable diseases (NCD) share predisposing risk factors. TB-associated NCD might cluster within households affected with TB requiring shared prevention and care strategies. We conducted an individual participant data meta-analysis of national TB prevalence surveys to determine whether NCD cluster in members of households with TB. We identified eligible surveys that reported at least one NCD or NCD risk factor through the archive maintained by the World Health Organization and searching in Medline and Embase from 1 January 2000 to 10 August 2021, which was updated on 23 March 2023. We compared the prevalence of NCD and their risk factors between people who do not have TB living in households with at least one person with TB (members of households with TB), and members of households without TB. We included 16 surveys (n = 740,815) from Asia and Africa. In a multivariable model adjusted for age and gender, the odds of smoking was higher among members of households with TB (adjusted odds ratio (aOR) 1.23; 95% CI: 1.11-1.38), compared with members of households without TB. The analysis did not find a significant difference in the prevalence of alcohol drinking, diabetes, hypertension, or BMI between members of households with and without TB. Studies evaluating household-wide interventions for smoking to reduce its dual impact on TB and NCD may be warranted. Systematically screening for NCD using objective diagnostic methods is needed to understand the actual burden of NCD and inform comprehensive interventions.

20.
Am J Physiol Renal Physiol ; 304(11): F1347-57, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23467424

RESUMO

Alterations in the podocyte actin cytoskeleton have been implicated in the development of proteinuric kidney diseases. In the present study, we evaluated the effect of HIV on the podocyte actin cytoskeleton and the mechanism involved. We hypothesized that HIV may be compromising the actin cytoskeleton via downregulation of the vitamin D receptor (VDR) of conditionally immortalized differentiated human podocytes (CIDHPs). HIV-transduced podocytes (HIV/CIDHPs) not only displayed downregulation of VDR but also showed activation of the renin-angiotensin system (RAS) in the form of enhanced expression of renin and increased production of ANG II. Moreover, CIDHPs lacking VDR displayed enhanced ANG II production, and treatment of HIV/CIDHPs with EB1089 (vitamin D3; VD) attenuated ANG II production. HIV/CIDHPs as well as ANG II-treated CIDHPs exhibited enhanced expression of cathepsin (CTS) L. Additionally, losartan (an ANG II type I receptor blocker) inhibited both HIV- and ANG II-induced podocyte cathepsin L expression. Furthermore, VD downregulated HIV-induced podocyte CTSL expression. Both losartan and free radical scavengers attenuated HIV- and ANG II-induced podocyte reactive oxygen species (ROS) generation. HIV also led to cytosolic CTSL accumulation through enhancement of podocyte lysosomal membrane permeabilization; on the other hand, VD, losartan, and superoxide dismutase (SOD) attenuated HIV-induced enhanced podocyte cytosolic CTSL accumulation. Morphological evaluation of HIV/CIDHPs revealed sparse actin filaments and attenuated expression of dynamin. Interestingly, podocytes lacking CTSL displayed enhanced dynamin expression, and HIV/CIDHPs expressing CTSL exhibited downregulation of dynamin. These findings indicate that HIV-induced downregulation of podocyte VDR and associated RAS activation and cytosolic CTSL accumulation compromised the actin cytoskeleton.


Assuntos
Actinas , Citoesqueleto/ultraestrutura , Regulação para Baixo , HIV-1/fisiologia , Podócitos/virologia , Receptores de Calcitriol/genética , Nefropatia Associada a AIDS/virologia , Angiotensina II/biossíntese , Catepsina L/genética , Expressão Gênica , Infecções por HIV/patologia , Infecções por HIV/fisiopatologia , HIV-1/genética , Humanos , Estresse Oxidativo , Podócitos/ultraestrutura , Receptores de Calcitriol/fisiologia , Sistema Renina-Angiotensina/fisiologia , Transdução Genética , Transfecção
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