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1.
Immunol Invest ; 53(2): 224-240, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38095846

RESUMEN

BACKGROUND: Previous studies have explored the role of AKT protein in anti-apoptotic/proliferative activities. However, there has been a lack of information regarding the role of Akt in association with cytokines expression in HBV-related (wild type HBV and HBV with mutations of 'a' determinant region) studies either in the case of HBV infection or in transfected hepatoma cells. The present study tries to determine the role of Akt and cytokines expression in the presence of small surface gene mutants in the hepatoma cell line. METHODS: Mutations of 'a' determinant region, viz. sA128V and sG145R, were created in wild-type pHBV1.3 by site-directed mutagenesis and transfected in hepatoma cell line. Secretory levels of HBsAg in the wild type as well as in both the mutants were analyzed by ELISA. Apoptotic analysis of transfected cells was studied by flow cytometry. Expression analysis of Akt and cytokines (TNF-alpha, IL-6, and IFN-gamma) was done by qPCR. RESULTS: The presence of significantly more alive cells in sG145R than sA128V transfected cells may be due to the up-regulation of the Akt gene expression. Cytokines expression was nearly similar between sA128V and wild-type pHBV1.3 transfected cells. Presence of sG145R showed dramatically high cytokines expression than sA128V and wild-type pHBV1.3. CONCLUSION: Cytokines expression predominantly contributes to the detrimental effects associated with the 'a' determinant region mutations particularly sG145R mutant. It may also be inferred that mechanisms associated with cellular apoptosis apparently do not play any major role to assign the 'a' determinant small surface gene mutation(s) for their pathological outcome.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Virus de la Hepatitis B/genética , Carcinoma Hepatocelular/genética , Antígenos de Superficie de la Hepatitis B/genética , Citocinas/genética , Proteínas Proto-Oncogénicas c-akt , Mutación , Neoplasias Hepáticas/genética , Línea Celular , Apoptosis/genética , ADN Viral/análisis , ADN Viral/genética , ADN Viral/farmacología
2.
Oxid Med Cell Longev ; 2023: 2297559, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38155869

RESUMEN

The global prevalence of chronic obstructive pulmonary disease (COPD) has increased over the last decade and has emerged as the third leading cause of death worldwide. It is characterized by emphysema with prolonged airflow limitation. COPD patients are more susceptible to COVID-19 and increase the disease severity about four times. The most used drugs to treat it show numerous side effects, including immune suppression and infection. This review discusses a narrative opinion and critical review of COPD. We present different aspects of the disease, from cellular and inflammatory responses to cigarette smoking in COPD and signaling pathways. In addition, we highlighted various risk factors for developing COPD apart from smoking, like occupational exposure, pollutants, genetic factors, gender, etc. After the recent elucidation of the underlying inflammatory signaling pathways in COPD, new molecular targeted drug candidates for COPD are signal-transmitting substances. We further summarize recent developments in biomarker discovery for COPD and its implications for disease diagnosis. In addition, we discuss novel drug targets for COPD that could be explored for drug development and subsequent clinical management of cardiovascular disease and COVID-19, commonly associated with COPD. Our extensive analysis of COPD cause, etiology, diagnosis, and therapeutic will provide a better understanding of the disease and the development of effective therapeutic options. In-depth knowledge of the underlying mechanism will offer deeper insights into identifying novel molecular targets for developing potent therapeutics and biomarkers of disease diagnosis.


Asunto(s)
COVID-19 , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Pulmón , Factores de Riesgo , COVID-19/complicaciones , Prueba de COVID-19
3.
Int J Biol Macromol ; 244: 125405, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37336383

RESUMEN

Protein glycation and aggregation have a pivotal role in many diseases including diabetes and neurodegenerative disorders. N-acetyl aspartate (NAA), an osmolyte derived from L-aspartic acid, is one of the most abundant metabolites in the mammalian brain. Although NAA is supposed to be a substitute for a neuronal marker, its function is not fully elucidated. Herein, we have investigated the effect of NAA on glycation, AGEs formation and aggregation of irisin. AGE-specific fluorescence showed strong inhibition of AGEs formation in the presence of NAA, demonstrating its anti-glycating property. The aggregates present in MG-modified irisin were also reduced by NAA, which was confirmed by Thioflavin T fluorescence and fluorescence microscopy. Further, for the explanation of the strong anti-glycating potential of NAA, the interaction between irisin and NAA was also examined. Interaction studies involving steady-state fluorescence and molecular docking demonstrated that hydrogen bonding and salt bridges by NAA stabilize the irisin. It was found that glycation-prone residues i.e., lysine and arginine are specifically involved in the interaction which might prevent them from getting modified during the process of glycation. This study for the first time reported the antiglycating potential of NAA which can be implicated in the therapeutic management of various glycation-related complications.


Asunto(s)
Ácido Aspártico , Reacción de Maillard , Animales , Ácido Aspártico/metabolismo , Simulación del Acoplamiento Molecular , Fibronectinas/metabolismo , Encéfalo/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Mamíferos/metabolismo
4.
ACS Omega ; 8(16): 14273-14289, 2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37125123

RESUMEN

Hepatitis, liver cirrhosis, and hepatocellular carcinoma are all manifestations of chronic hepatitis B. Its pathogenesis and molecular mechanism remain mysterious. As medical science progresses, different models are being used to study the disease from the physiological and molecular levels. Animal models have played an unprecedented role in achieving in-depth knowledge of the disease while posing no risk of harming humans throughout the study. The scarcity of acceptable animal models has slowed progress in hepatitis B virus (HBV) research and preclinical testing of antiviral medicines since HBV has a narrow species tropism and exclusively infects humans and higher primates. The development of human chimeric mice was supported by a better understanding of the obstacles to interspecies transmission, which has substantially opened the way for HBV research in vivo and the evaluation of possible chronic hepatitis B therapeutics. Animal models are cumbersome to handle, not accessible, and expensive. Hence, it is herculean to investigate the HBV replication cycle in animal models. Therefore, it becomes essential to build a splendid in vitro cell culture system to demonstrate the mechanisms attained by the HBV for its multiplication and sustenance. We also addressed the advantages and caveats associated with different models in examining HBV.

5.
Gut Pathog ; 15(1): 11, 2023 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36895013

RESUMEN

BACKGROUND: Interferon and nucleos(t)ide analogues are current therapeutic treatments for chronic Hepatitis B virus (HBV) infection with the limitations of a functional cure. Chrysin (5, 7-dihydroxyflavone) is a natural flavonoid, known for its antiviral and hepatoprotective activities. However, its anti-HBV activity is unexplored. METHODS: In the present study, the anti-hepatitis B activity of chrysin was investigated using the in vitro experimental cell culture model, HepG2 cells. In silico studies were performed where chrysin and lamivudine (used here as a positive control) were docked with high mobility group box 1 protein (HMGB1). For the in vitro studies, wild type HBV genome construct (pHBV 1.3X) was transiently transfected in HepG2. In culture supernatant samples, HBV surface antigen (HBsAg) and Hepatitis B e antigen (HBeAg) were measured by enzyme-linked immunosorbent assay (ELISA). Secreted HBV DNA and intracellular covalently closed circular DNA (cccDNA) were measured by SYBR green real-time PCR. The 3D crystal structure of HMGB1 (1AAB) protein was developed and docked with the chrysin and lamivudine. In silico drug-likeness, Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) properties of finest ligands were performed by using SwissADME and admetSAR web servers. RESULTS: Data showed that chrysin significantly decreases HBeAg, HBsAg secretion, supernatant HBV DNA and cccDNA, in a dose dependent manner. The docking studies demonstrated HMGB1 as an important target for chrysin as compared to lamivudine. Chrysin revealed high binding affinity and formed a firm kissing complex with HMGB1 (∆G = - 5.7 kcal/mol), as compared to lamivudine (∆G = - 4.3 kcal/mol), which might be responsible for its antiviral activity. CONCLUSIONS: The outcome of our study establishes chrysin as a new antiviral against HBV infection. However, using chrysin to treat chronic HBV disease needs further endorsement and optimization by in vivo studies in animal models.

6.
J Cell Biochem ; 124(1): 156-168, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36502526

RESUMEN

Glycation of proteins leading to the formation of advanced glycation end products (AGEs) has been demonstrated to contribute to the pathogenesis of several diseases. Irisin is a clinically significant protein, putatively involved in obesity, diabetes, and neurological disorders. This study aimed to monitor the methyl-glyoxal (MG) induced AGEs and aggregate formation of irisin, as a function of time, employing multispectroscopic and microscopic approaches. ANS fluorescence suggested a molten globule-like state on Day 6, followed by the formation of irisin AGEs adducts, as confirmed by AGE-specific fluorescence. Glycation of irisin led to aggregate formation, which was characterized by Thioflavin T fluorescence, CD spectroscopy, and microscopic studies. These aggregates were confirmed by exploiting fluorescence microscopy, confocal, and transmission electron microscopy. Molecular docking was performed to determine the crucial residues of irisin involved in irisin-MG interaction. Usually, MG is present in trace amounts as a metabolic by-product in the body, which is found to be elevated in diseased conditions viz. diabetes and Alzheimer's disease. This study characterized the AGEs and aggregates of clinically important protein, irisin; and since MG level has been found to be increased in various pathological conditions, this study provides a clinical perspective. There is a possibility that elevated MG concentrations might glycate irisin resulting in reduced irisin levels as reported in pathological conditions. However, further investigations are required to prove it.


Asunto(s)
Diabetes Mellitus , Productos Finales de Glicación Avanzada , Humanos , Fibronectinas , Productos Finales de Glicación Avanzada/metabolismo , Simulación del Acoplamiento Molecular , Piruvaldehído/farmacología
7.
ACS Omega ; 7(28): 24066-24081, 2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35874215

RESUMEN

Hepatitis B virus infection (HBV) is still a big health problem across the globe. It has been linked to the development of liver cirrhosis and hepatocellular carcinoma and can trigger different types of liver damage. Existing medicines are unable to disable covalently closed circular DNA (cccDNA), which may result in HBV persistence and recurrence. The current therapeutic goal is to achieve a functional cure, which means HBV-DNA no longer exists when treatment stops and the absence of HBsAg seroclearance. However, due to the presence of integrated HBV DNA and cccDNA functional treatment is now regarded to be difficult. In order to uncover pathways for potential therapeutic targets and identify medicines that could result in large rates of functional cure, a thorough understanding of the virus' biology is required. The proteins of the virus and episomal cccDNA are thought to be critical for the management and support of the HBV replication cycle as they interact directly with the host proteome to establish the best atmosphere for the virus while evading immune detection. The breakthroughs of host dependence factors, cccDNA transcription, epigenetic regulation, and immune-mediated breakdown have all produced significant progress in our understanding of cccDNA biology during the past decade. There are some strategies where cccDNA can be targeted either in a direct or indirect way and are presently at the point of discovery or preclinical or early clinical advancement. Editing of genomes, techniques targeting host dependence factors or epigenetic gene maintenance, nucleocapsid modulators, miRNA, siRNA, virion secretory inhibitors, and immune-mediated degradation are only a few examples. Though cccDNA approaches for direct targeting are still in the early stages of development, the assembly of capsid modulators and immune-reliant treatments have made it to the clinic. Clinical trials are currently being conducted to determine their efficiency and safety in patients, as well as their effect on viral cccDNA. The influence of recent breakthroughs in the development of new treatment techniques on cccDNA biology is also summarized in this review.

8.
Int J Mol Sci ; 23(11)2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35682643

RESUMEN

The prevalence of Alzheimer's disease (AD) has been a major health concern for a long time. Despite recent progress, there is still a strong need to develop effective disease-modifying therapies. Several drugs have already been approved to retard the progression of AD-related symptoms; however, there is a need to develop an effective carrier system for the delivery of drugs to combat such diseases. In recent years, various biological macromolecules, including proteins, have been used as carriers for drug delivery. Irisin is a beneficial hormone in such diseases, including AD and related pathologies. Herein, the interaction mechanism of irisin with AD drugs such as memantine, galantamine, and fluoxetine is investigated. Fluorescence studies revealed that the above drugs bind to irisin with significant affinity, with fluoxetine having the highest binding affinity. Isothermal titration calorimetry (ITC) complemented the spontaneous binding of these drugs with irisin, delineating various associated thermodynamic and binding parameters. Molecular docking further validated the fluorescence and ITC results and unfolded the mechanism that hydrogen bonding governs the binding of fluoxetine to irisin with a significant binding score, i.e., -6.3 kcal/mol. We believe that these findings provide a promising solution to fight against AD as well as a platform for further research to utilize irisin in the drug-delivery system for an effective therapeutic strategy.


Asunto(s)
Enfermedad de Alzheimer , Fibronectinas , Enfermedad de Alzheimer/tratamiento farmacológico , Sitios de Unión , Calorimetría/métodos , Fluoxetina , Humanos , Simulación del Acoplamiento Molecular , Preparaciones Farmacéuticas , Unión Proteica , Espectrometría de Fluorescencia , Termodinámica
9.
Int J Biol Macromol ; 207: 1022-1037, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35358582

RESUMEN

TANK-binding kinase 1 (TBK1) plays a fundamental role in regulating the cellular responses and controlling several signaling cascades. It regulates inflammatory, interferon, NF-κB, autophagy, and Akt pathways. Post-translational modifications (PTM) of TBK1 control its action and subsequent cellular signaling. The dysregulation of the TBK1 pathway is correlated to many pathophysiological conditions, including cancer, that implicates the promising therapeutic advantage for targeting TBK1. The present study summarizes current updates on the molecular mechanisms and cancer-inducing roles of TBK1. Designed inhibitors of TBK1 are considered a potential therapeutic agent for several diseases, including cancer. Data from pre-clinical tumor models recommend that the targeting of TBK1 could be an attractive strategy for anti-tumor therapy. This review further highlighted the therapeutic potential of potent and selective TBK1 inhibitors, including Amlexanox, Compound II, BX795, MRT67307, SR8185 AZ13102909, CYT387, GSK8612, BAY985, and Domainex. These inhibitors may be implicated to facilitate therapeutic management of cancer and TBK1-associated diseases in the future.


Asunto(s)
Antineoplásicos , Neoplasias , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Humanos , FN-kappa B/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Transducción de Señal
10.
Molecules ; 27(3)2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35164383

RESUMEN

A sedentary lifestyle or lack of physical activity increases the risk of different diseases, including obesity, diabetes, heart diseases, certain types of cancers, and some neurological diseases. Physical exercise helps improve quality of life and reduces the risk of many diseases. Irisin, a hormone induced by exercise, is a fragmented product of FNDC5 (a cell membrane protein) and acts as a linkage between muscles and other tissues. Over the past decade, it has become clear that irisin is a molecular mimic of exercise and shows various beneficial effects, such as browning of adipocytes, modulation of metabolic processes, regulation of bone metabolism, and functioning of the nervous system. Irisin has a role in carcinogenesis; numerous studies have shown its impact on migration, invasion, and proliferation of cancer cells. The receptor of irisin is not completely known; however, in some tissues it probably acts via a specific class of integrin receptors. Here, we review research from the past decade that has identified irisin as a potential therapeutic agent in the prevention or treatment of various metabolic-related and other diseases. This article delineates structural and biochemical aspects of irisin and provides an insight into the role of irisin in different pathological conditions.


Asunto(s)
Fibronectinas/metabolismo , Enfermedades Metabólicas/metabolismo , Neoplasias/metabolismo , Animales , Carcinogénesis/metabolismo , Ejercicio Físico , Fibronectinas/análisis , Humanos , Enfermedades Metabólicas/fisiopatología , Modelos Moleculares , Neoplasias/fisiopatología , Conformación Proteica , Conducta Sedentaria , Transducción de Señal
11.
J Clin Med ; 10(21)2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34768321

RESUMEN

The gastrointestinal tract is the body's largest interface between the host and the external environment. People infected with SARS-CoV-2 are at higher risk of microbiome alterations and severe diseases. Recent evidence has suggested that the pathophysiological and molecular mechanisms associated with gastrointestinal complicity in SARS-CoV-2 infection could be explained by the role of angiotensin-converting enzyme-2 (ACE2) cell receptors. These receptors are overexpressed in the gut lining, leading to a high intestinal permeability to foreign pathogens. It is believed that SARS-CoV-2 has a lesser likelihood of causing liver infection because of the diminished expression of ACE2 in liver cells. Interestingly, an interconnection between the lungs, brain, and gastrointestinal tract during severe COVID-19 has been mentioned. We hope that this review on the molecular mechanisms related to the gastrointestinal disorders as well as neurological and hepatic manifestations experienced by COVID-19 patients will help scientists to find a convenient solution for this and other pandemic events.

12.
Mol Immunol ; 136: 65-72, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34087625

RESUMEN

Trauma remains a major public health problem worldwide, marked as the fourth leading cause of death among all diseases. Trauma patients who survived at initial stages in the Emergency Department (ED), have significantly higher chances of mortality due to sepsis associated complications in the ICU at the later stage. There is paucity of literature regarding the role of circulating monocytes subsets and development of sepsis complications following trauma haemorrhagic shock (THS). The study was conducted to investigate the circulating level of monocyte subsets (Classical, Inflammatory, and Patrolling) and its functions in patients with acute post-traumatic sepsis. A total 72, THS patients and 30 age matched healthy controls were recruited. Blood samples were collected at different time points on days 1, 7, and 14 to measure the serum levels of cytokines by Cytometric bead assay (CBA), for the immunophenotyping of monocytes subsets, and also for the cell sorting of monocytes subsets for the functional studies. The circulating levels of monocytes subsets were found to be significantly differs among THS patients, who developed sepsis when compared with others who did not. The levels of patrolling monocytes were elevated in THS patients who developed sepsis and showed negative correlation with Sequential organ failure assessment (SOFA) score on days 7 and 14. Classical monocytes responded strongly to bacterial TLR-agonist (LPS) and produced anti-inflammatory cytokines, whereas patrolling monocytes responded with viral TLR agonist TLR-7/8 (R848) and produced inflammatory cytokines in post-traumatic sepsis patients. In conclusion, this study shows disparity in the behaviour of monocytes subsets in patients with acute post-traumatic sepsis.


Asunto(s)
Citocinas/sangre , Septicemia Hemorrágica/inmunología , Septicemia Hemorrágica/patología , Monocitos/clasificación , Monocitos/inmunología , Adulto , Femenino , Septicemia Hemorrágica/microbiología , Humanos , Lipopolisacáridos , Masculino , Índices de Gravedad del Trauma , Heridas y Lesiones/inmunología , Heridas y Lesiones/patología
13.
Front Genet ; 12: 633341, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33777103

RESUMEN

Hepatitis B virus X protein C-terminal 127 amino acid truncation is often found expressed in hepatocellular carcinoma (HCC) tissue samples. The present in vitro study tried to determine the role of this truncation mutant in the hepatitis B-related liver diseases such as fibrosis, cirrhosis, HCC, and metastasis. HBx gene and its 127 amino acid truncation mutant were cloned in mammalian expression vectors and transfected in human hepatoma cell line. Changes in cell growth/proliferation, cell cycle phase distribution, expression of cell cycle regulatory genes, mitochondrial depolarization, and intracellular reactive oxygen species (ROS) level were analyzed. Green fluorescent protein (GFP)-tagged version of HBx and the truncation mutant were also created and the effects of truncation on HBx intracellular expression pattern and localization were studied. Effect of time lapse on protein expression pattern was also analyzed. The truncation mutant of HBx is more efficient in inducing cell proliferation, and causes more ROS production and less mitochondrial depolarization as compared with wild type (wt) HBx. In addition, gene expression is altered in favor of carcinogenesis in the presence of the truncation mutant. Furthermore, mitochondrial perinuclear aggregation is achieved earlier in the presence of the truncation mutant. Therefore, HBx C-terminal 127 amino acid truncation might be playing important roles in the development of hepatitis B-related liver diseases by inducing cell proliferation, altering gene expression, altering mitochondrial potential, inducing mitochondrial clustering and oxidative stress, and changing HBx expression pattern.

14.
ACS Omega ; 6(11): 7910-7921, 2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33778302

RESUMEN

This study was aimed to study the interaction between purified irisin and rivastigmine tartrate (RT), a cholinesterase inhibitor used in Alzheimer's therapy. Irisin mainly promotes brown fat-like features in white adipose tissues; however, it has some important role in the nervous system also, i.e., capable of opposing synapse and memory failure in Alzheimer's disease (AD). The recombinant protein was purified by Ni-NTA chromatography and characterized using spectroscopic and in silico techniques. Further, the mechanism of interaction between irisin and RT was investigated using various biophysical techniques. Fluorescence quenching studies suggested that there exists a moderate binding between irisin and RT with a binding constant (K) of 104 M-1 and the irisin-RT complex is guided by a combination of both static and dynamic modes of quenching. Thermodynamic parameters suggested the reaction to be driven by hydrogen bonding, making it specific. FTIR and CD spectroscopy suggested no secondary structural alterations in irisin in the presence of RT. Molecular docking investigation provided an insight into the important residues that play a key role in irisin-RT interactions. This study delineates an important finding in AD therapy and can provide a platform further to explore the potential of irisin in AD treatment.

15.
J Infect Public Health ; 13(12): 1912-1919, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33148496

RESUMEN

BACKGROUND: Dengue fever has become a hampering menace in New Delhi India, since the disease has become hyperendemic, due to circulation of multiple serotypes of dengue virus (DENV). This hyperendemicity poses a greater risk of secondary infections in human health system. This is a major issue which leads to apprehension amongst the researchers and health organizations and thus requires regular epidemiological surveillance. METHODS: We analyzed the prevalence and serotypic distribution of dengue fever cases reported from the Southern part of New Delhi during continued surveillance from 2011 to 2017. The blood samples for the investigation were obtained from the patients suspected with dengue fever attending the OPD at a local Health Centre. The data for 2011-2016 was already published from our laboratory. The samples collected during 2017 were serotyped and characterized in the present study. RESULTS: A total of 565 samples (59%) were positive for DENV of 958 samples tested by RT-PCR during 7 years (2011-2017). Our study has shown that most infections were caused by DENV-2 during 2011-2015. The data has shown occurrence of all four serotypes of DENV during 2015 and predominance of DENV-3 in 2016 and 2017. Further, predominant combination of DENV-1 and DENV-2 was found in most of the co-infections. To the best of our knowledge this is the first study showing the epidemiological trend of dengue fever in reference to the circulating DENV serotypes and co-infections from a hyperendemic region of New Delhi during 2011-2017. CONCLUSIONS: This hyperendemic pattern of DENV and instantaneous shift in circulation of its serotypes is likely pose a greater risk of secondary infections. Inclusion of comprehensive community and hospital surveillance of dengue fever will assist in formulation and implementation of effective control measures.


Asunto(s)
Virus del Dengue , Dengue , Dengue/epidemiología , Virus del Dengue/genética , Genotipo , Humanos , India/epidemiología , Serogrupo
16.
Oxid Med Cell Longev ; 2019: 1297484, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31772697

RESUMEN

Hepatitis B virus (HBV) infection is one of the major causes of liver diseases, which can lead to hepatocellular carcinoma. The role of HBV envelope proteins is crucial in viral morphogenesis, infection, and propagation. Thus, blocking the pleiotropic functions of these proteins especially the PreS1 and PreS2 domains of the large surface protein (LHBs) is a promising strategy for designing efficient antivirals against HBV infection. Unfortunately, the structure of the LHBs protein has not been elucidated yet, and it seems that any structure-based drug discovery is critically dependent on this. To find effective inhibitors of LHBs, we have modeled and validated its three-dimensional structure and subsequently performed a virtual high-throughput screening against the ZINC database using RASPD and ParDOCK tools. We have identified four compounds, ZINC11882026, ZINC19741044, ZINC00653293, and ZINC15000762, showing appreciable binding affinity with the LHBs protein. The drug likeness was further validated using ADME screening and toxicity analysis. Interestingly, three of the four compounds showed the formation of hydrogen bonds with amino acid residues lying in the capsid binding region of the PreS1 domain of LHBs, suggesting the possibility of inhibiting the viral assembly and maturation process. The identification of potential lead molecules will help to discover more potent inhibitors with significant antiviral activities.


Asunto(s)
Hepatitis B/prevención & control , Simulación del Acoplamiento Molecular/métodos , Proteínas del Envoltorio Viral/metabolismo , Humanos
17.
J Cell Biochem ; 120(10): 17858-17871, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31310366

RESUMEN

Hepatitis B virus (HBV) genome consists of circular partially double stranded DNA of 3.2 kb size which gets converted into covalently closed circular DNA (cccDNA) during its life cycle. It then acts as a template for formation of pregenomicRNA (pgRNA) of 3.5 kb. Absence of appropriate animal models prompted a need to establish a better in vitro culture system to uncover the propagation and survival mechanisms of the virus. There is scarcity of data to represent the significance of varying length of replication competent viral genome on the secretion of viral secretory proteins/antigens and in turn on the overall effects on the accomplishment of the viral life cycle. The present study was undertaken to ascertain a suitable replication competent construct in which the viral life cycle of HBV with varying clinical relevance can be studied efficiently. Two constructs (pHBV 1.3 and pHBV 1X) of different sizes were used to transfect hepatoma cells and consequently the secretory antigens were monitored. In vector free approach (pHBV 1X), 3.2 kb viral DNA is directly transfected in the culture system whereas in vector mediated approach more than full length of viral genome is cloned in a vector (pHBV 1.3X) and transfected to obtain a 3.5 kb pgRNA intermediate. HBV secretes two important antigens; HBsAg and HBeAg. HBsAg is a hallmark of infection and is the first to be secreted in the blood stream whereas HBeAg is a secretory protein and remains associated with the viral replication. The construct pHBV 1.3X referring to as more than full length, by virtue of being capable of undergoing transcription without the synthesis of cccDNA intermediate (unlike the clinical situation where an intermediate step of cccDNA synthesis is an essential component to initiate the viral life cycle) appears to be better system for studying viral life cycle in in vitro culture system. The reasons could be assigned to the fact that as low as 100 ng of viral DNA was shown to quantify the replicative phenotypes with this construct. The better efficiency of this construct at prima facie, appears to be mediated through the significantly higher levels of pgRNA transcript during the viral life cycle.


Asunto(s)
Replicación del ADN/genética , Genoma Viral , Antígenos de Superficie de la Hepatitis B/metabolismo , Antígenos e de la Hepatitis B/metabolismo , Virus de la Hepatitis B/genética , Línea Celular Tumoral , ADN Viral/genética , Sitios Genéticos , Vectores Genéticos/metabolismo , Humanos , Plásmidos/genética , Reproducibilidad de los Resultados , Factores de Tiempo
18.
Int J Biol Macromol ; 136: 1076-1085, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31233792

RESUMEN

Pyruvate dehydrogenase kinase 3 (PDK3) is a mitochondrial protein, has recently been considered as a potential pharmacological target for varying types of cancer. Here, we report the binding mechanism of quercetin to the PDK3 by using molecular docking, simulation, fluorescence spectroscopy and isothermal titration calorimetric assays. Molecular docking along with simulation provided an in-depth analysis of protein-ligand interactions. We have observed that quercetin interacts to the important residues of active site cavity of PDK3 and shows a well-ordered conformational fitting. The stability of quercetin-PDK3 complex is maintained by several non-covalent interactions throughout the simulation. To complement in silico findings with the experiments, we have successfully expressed and purified human PDK3. Both fluorescence and isothermal titration calorimetric experiments showed excellent binding affinity of quercetin to the PDK3. Kinase inhibition assay further revealed a significant inhibitory potential of quercetin to the PDK3 with the IC50 values in µM range. Quercetin is non-toxic to HEK293, and significantly inhibits the proliferation of cancer (HepG2 and A549) cell lines. All these observations clearly indicate that quercetin may be further evaluated as promising therapeutic molecule for PDK3 with required modifications and in vivo validation.


Asunto(s)
Antineoplásicos/farmacología , Inhibidores Enzimáticos/farmacología , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/antagonistas & inhibidores , Quercetina/farmacología , Antineoplásicos/metabolismo , Proliferación Celular/efectos de los fármacos , Inhibidores Enzimáticos/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Concentración 50 Inhibidora , Simulación del Acoplamiento Molecular , Estructura Secundaria de Proteína/efectos de los fármacos , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/química , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/metabolismo , Quercetina/metabolismo
19.
Free Radic Res ; 53(5): 473-485, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31117842

RESUMEN

Gallbladder cancer (GBC) is a fatal condition with dismal prognosis and aggressive local invasiveness; and with uncharacterised molecular pathology relating to non-specific therapeutic modalities. Given the importance of oxidative stress in chronic diseases and carcinogenesis, and the lacunae in literature regarding its role in gallbladder diseases, this study aimed to study the involvement of oxidative stress and deregulation in the base excision repair (BER) pathway in the pathogenesis of gallbladder diseases including GBC. This study involved patients from the North-East Indian population, where the numbers of reported cases are increasing rapidly and alarmingly. Oxidative stress, based on 8-OH-dG levels, was found to be significantly higher in gallbladder anomalies (cholelithiasis [CL] and cholecystitis [CS]) and GBC at the plasma and DNA level, and was associated with GBC severity. The expressions of key BER pathway genes were downregulated in gallbladder anomalies and GBC compared to controls, and in GBC compared to both non-neoplastic controls and gallbladder anomalies. Expression of XRCC1 and hOGG1 was significantly associated with both susceptibility and severity of GBC. The XRCC1 codon280 polymorphism was associated with disease susceptibility; and significantly higher oxidative stress was observed in hOGG1 genotypic variants. The genomes of GBC patients were found to be more hypermethylated compared to controls, with the promoters of XRCC1 and hOGG1 being hypermethylated and, therefore, being silenced. This study underlined the prognostic significance of the oxidative stress marker 8-OH-dG and BER pathway genes, especially hOGG1 and XRCC1, in gallbladder anomalies and GBC, as well as stated their potential for therapeutic targeting.


Asunto(s)
Colecistitis/genética , Colelitiasis/genética , ADN Glicosilasas/genética , Reparación del ADN , Neoplasias de la Vesícula Biliar/genética , Regulación Neoplásica de la Expresión Génica , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X/genética , 8-Hidroxi-2'-Desoxicoguanosina/metabolismo , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Colecistitis/complicaciones , Colecistitis/patología , Colecistitis/cirugía , Colelitiasis/complicaciones , Colelitiasis/patología , Colelitiasis/cirugía , ADN Glicosilasas/metabolismo , Metilación de ADN , Femenino , Vesícula Biliar/metabolismo , Vesícula Biliar/patología , Vesícula Biliar/cirugía , Neoplasias de la Vesícula Biliar/complicaciones , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/cirugía , Predisposición Genética a la Enfermedad , Humanos , India , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estrés Oxidativo/genética , Polimorfismo de Nucleótido Simple , Pronóstico , Regiones Promotoras Genéticas , Índice de Severidad de la Enfermedad , Transducción de Señal , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X/metabolismo
20.
PLoS Negl Trop Dis ; 10(3): e0004511, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26977703

RESUMEN

Dengue fever is the most important arboviral disease in the tropical and sub-tropical countries of the world. Delhi, the metropolitan capital state of India, has reported many dengue outbreaks, with the last outbreak occurring in 2013. We have recently reported predominance of dengue virus serotype 2 during 2011-2014 in Delhi. In the present study, we report molecular characterization and evolutionary analysis of dengue serotype 2 viruses which were detected in 2011-2014 in Delhi. Envelope genes of 42 DENV-2 strains were sequenced in the study. All DENV-2 strains grouped within the Cosmopolitan genotype and further clustered into three lineages; Lineage I, II and III. Lineage III replaced lineage I during dengue fever outbreak of 2013. Further, a novel mutation Thr404Ile was detected in the stem region of the envelope protein of a single DENV-2 strain in 2014. Nucleotide substitution rate and time to the most recent common ancestor were determined by molecular clock analysis using Bayesian methods. A change in effective population size of Indian DENV-2 viruses was investigated through Bayesian skyline plot. The study will be a vital road map for investigation of epidemiology and evolutionary pattern of dengue viruses in India.


Asunto(s)
Virus del Dengue/clasificación , Virus del Dengue/genética , Dengue/virología , Evolución Molecular , Variación Genética , Genotipo , Adulto , Teorema de Bayes , Análisis por Conglomerados , Virus del Dengue/aislamiento & purificación , Productos del Gen env/genética , Humanos , India , Datos de Secuencia Molecular , Filogenia , Análisis de Secuencia de ADN , Serogrupo
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