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1.
Curr Issues Mol Biol ; 44(7): 2825-2841, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35877418

RESUMEN

Diabetic peripheral neuropathy (DPN) is a common diabetes complication (DM). Aldose reductase -2 (ALR-2) is an oxidoreductase enzyme that is most extensively studied therapeutic target for diabetes-related complications that can be inhibited by epalrestat, which has severe adverse effects; hence the discovery of potent natural inhibitors is desired. In response, a pharmacophore model based on the properties of eplarestat was generated. The specified pharmacophore model searched the NuBBEDB database of natural compounds for prospective lead candidates. To assess the drug-likeness and ADMET profile of the compounds, a series of in silico filtering procedures were applied. The compounds were then put through molecular docking and interaction analysis. In comparison to the reference drug, four compounds showed increased binding affinity and demonstrated critical residue interactions with greater stability and specificity. As a result, we have identified four potent inhibitors: ZINC000002895847, ZINC000002566593, ZINC000012447255, and ZINC000065074786, that could be used as pharmacological niches to develop novel ALR-2 inhibitors.

2.
Biomed Pharmacother ; 150: 112985, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35658219

RESUMEN

Diabetes is a complicated multifactorial disorder in which the patient generally observes polyphagia, polydipsia, and polyuria due to uncontrolled growth in blood sugar levels. For its management, the pharmaceutical industry is working day and night to find a better drug with no or least toxicity. That's why nowadays a more focused branch is to use herbal phytoconstituents for its prevention. Shikonin is a naphthoquinone natural dye that is isolated from the plants of the Boraginaceae family and has proven its role as an anti-cancer, anti-inflammatory, and anti-gonadotrophic agent. In our previous study, we have published its anti-diabetic action by inhibiting the enzyme protein tyrosine phosphatase 1B. In this study, we were more focused on finding out the role of Shikonin and its pharmacophores by inhibiting the action of aldose reductase (AR) enzyme. The study was conducted using pharmacophore modeling, molecular docking, and molecular dynamics simulation studies. The absorption, distribution, metabolism, excretion (ADME), and toxicity profile were also evaluated in this study. Along with all the computational biology parameters we also focused on the in vitro activity and kinetic study of inhibitory activity of Shikonin against aldose reductase.


Asunto(s)
Diabetes Mellitus , Naftoquinonas , Aldehído Reductasa/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Humanos , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Simulación del Acoplamiento Molecular , Naftoquinonas/farmacología , Naftoquinonas/uso terapéutico
3.
Cell Mol Biol (Noisy-le-grand) ; 68(11): 90-96, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37114302

RESUMEN

PKP1 has been crucially involved in enhancing the MYC translation leading to lung carcinogenesis via evading numerous tumour-suppressing checkpoint systems. Plakophilin 1(PKP1) is the part of armadillo and plakophilin gene families and it is a necessary component of desmosomes. Several researches reported PKP1 protein as one of the most overexpressed proteins in human lung cancer. Therefore, we have designed our research towards elucidating better plant-based compounds as drug candidates for the management of lung cancer with minimal adverse effects over other chemotherapeutic drugs such as afatinib. This study comprises forty-six flavonoids for targeting PKP1 using in silico approaches that were not used earlier as an anti-cancerous agent targeting PKP1 in lung cancer treatment. Flavonoids are plant-derived natural compounds that exhibited enormous anti-cancerous potential against several human cancers. NPACT database was used to screen potent flavonoids that have not been used to target the PKP1 protein in lung cancer. Patch Dock and CB Dock were employed to elucidate the PKP1 (1XM9) inhibitory potential of selected flavonoids. Analysis with both the docking tools has revealed that calyxins I  showed maximum affinity in comparison to the standard drug, afatinib. Further PASS and BAS analyses were performed using SWISS ADME and molinspiration to investigate the pharmacokinetic profiling of potent flavonoids having significant binding energy. Visualization of complexes was done by using UCSF chimera. However, further detailed in vitro studies are needed to validate the candidature of calyxinsI for being developed as an anticancer drug for the management of lung cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Afatinib , Neoplasias Pulmonares/tratamiento farmacológico , Proteínas/metabolismo , Flavonoides/farmacología , Flavonoides/uso terapéutico , Placofilinas/genética , Placofilinas/metabolismo
4.
Cell Mol Biol (Noisy-le-grand) ; 67(1): 45-49, 2021 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-34817369

RESUMEN

The hunt for potential lead/drug molecules from different resources, especially from natural resources, for possible treatment of COVID-19 is ongoing. Several compounds have already been identified, but only a few are good enough to show potential against the virus. Among the identified druggable target proteins of SARS-CoV-2, this study focuses on non-structural RNA-dependent RNA polymerase protein (RdRp), a well-known enzyme for both viral genome replication and viral mRNA synthesis, and is therefore considered to be the primary target. In this study, the virtual screening followed by an in-depth docking study of the Compounds Library found that natural compound Cyclocurcumin and Silybin B have strong interaction with RdRp and much better than the remdesivir with free binding energy and inhibition constant value as êzŒ-6.29 kcal/mol and 58.39 µMêzŒ, and êzŒ-7.93kcal/mol and 45.3 µMêzŒ, respectively. The finding indicated that the selected hits (Cyclocurcumin and Silybin B) could act as non-nucleotide anti-polymerase agents, and can be further optimized as a potential inhibitor of RdRp by benchwork experiments.


Asunto(s)
Adenosina Monofosfato/análogos & derivados , Alanina/análogos & derivados , Antivirales/metabolismo , Productos Biológicos/metabolismo , COVID-19/metabolismo , ARN Polimerasa Dependiente de ARN de Coronavirus/metabolismo , Descubrimiento de Drogas/métodos , Simulación del Acoplamiento Molecular/métodos , Fitoquímicos/metabolismo , SARS-CoV-2/enzimología , Adenosina Monofosfato/química , Adenosina Monofosfato/metabolismo , Alanina/química , Alanina/metabolismo , Antivirales/química , Productos Biológicos/química , COVID-19/virología , Dominio Catalítico , ARN Polimerasa Dependiente de ARN de Coronavirus/antagonistas & inhibidores , ARN Polimerasa Dependiente de ARN de Coronavirus/química , Curcumina/análogos & derivados , Curcumina/química , Curcumina/metabolismo , Bases de Datos de Proteínas , Evaluación Preclínica de Medicamentos/métodos , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Fitoquímicos/química , Unión Proteica , Silibina/química , Silibina/metabolismo
5.
Molecules ; 26(13)2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34208908

RESUMEN

Diabetes mellitus is a multifactorial disease that affects both developing and developed countries and is a major public health concern. Many synthetic drugs are available in the market, which counteracts the associated pathologies. However, due to the propensity of side effects, there is an unmet need for the investigation of safe and effective drugs. This research aims to find a novel phytoconstituent having diminished action on blood glucose levels with the least side effects. Shikonin is a naturally occurring naphthoquinone dying pigment obtained by the roots of the Boraginaceae family. Besides its use as pigments, it can be used as an antimicrobial, anti-inflammatory, and anti-tumor agent. This research aimed to hypothesize the physicochemical and phytochemical properties of Shikonin's in silico interaction with protein tyrosine phosphate 1B, as well as it's in vitro studies, in order to determine its potential anti-diabetic impact. To do so, molecular docking experiments with target proteins were conducted to assess their anti-diabetic ability. Analyzing associations with corresponding amino acids revealed the significant molecular interactions between Shikonin and diabetes-related target proteins. In silico pharmacokinetics and toxicity profile of Shikonin using ADMET Descriptor, Toxicity Prediction, and Calculate Molecular Properties tools from Biovia Discovery Studio v4.5. Filter by Lipinski and Veber Rule's module from Biovia Discovery Studio v4.5 was applied to assess the drug-likeness of Shikonin. The in vitro studies exposed that Shikonin shows an inhibitory potential against the PTP1B with an IC50 value of 15.51 µM. The kinetics studies revealed that it has a competitive inhibitory effect (Ki = 7.5 M) on the enzyme system, which could be useful in the production of preventive and therapeutic agents. The findings of this research suggested that the Shikonin could be used as an anti-diabetic agent and can be used as a novel source for drug delivery.


Asunto(s)
Inhibidores Enzimáticos/química , Hipoglucemiantes/química , Simulación del Acoplamiento Molecular , Naftoquinonas/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Regulación Alostérica , Humanos , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Proteína Tirosina Fosfatasa no Receptora Tipo 1/química , Relación Estructura-Actividad
6.
Molecules ; 26(6)2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33799871

RESUMEN

Considering the urgency of the COVID-19 pandemic, we developed a receptor-based pharmacophore model for identifying FDA-approved drugs and hits from natural products. The COVID-19 main protease (Mpro) was selected for the development of the pharmacophore model. The model consisted of a hydrogen bond acceptor, donor, and hydrophobic features. These features demonstrated good corroboration with a previously reported model that was used to validate the present model, showing an RMSD value of 0.32. The virtual screening was carried out using the ZINC database. A set of 208,000 hits was extracted and filtered using the ligand pharmacophore mapping, applying the lead-like properties. Lipinski's filter and the fit value filter were used to minimize hits to the top 2000. Simultaneous docking was carried out for 200 hits for natural drugs belonging to the FDA-approved drug database. The top 28 hits from these experiments, with promising predicted pharmacodynamic and pharmacokinetic properties, are reported here. To optimize these hits as Mpro inhibitors and potential treatment options for COVID-19, bench work investigations are needed.


Asunto(s)
Antivirales/química , Antivirales/farmacología , Productos Biológicos/química , Productos Biológicos/farmacología , Tratamiento Farmacológico de COVID-19 , Receptores de Droga/metabolismo , Sitios de Unión , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Proteasas 3C de Coronavirus/química , Proteasas 3C de Coronavirus/metabolismo , Bases de Datos Farmacéuticas , Descubrimiento de Drogas , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Ligandos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Unión Proteica , Relación Estructura-Actividad Cuantitativa
7.
Molecules ; 26(8)2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33923734

RESUMEN

Mycobacterium tuberculosis (Mtb) is a deadly tuberculosis (TB)-causing pathogen. The proteasome is vital to the survival of Mtb and is therefore validated as a potential target for anti-TB therapy. Mtb resistance to existing antibacterial agents has enhanced drastically, becoming a worldwide health issue. Therefore, new potential therapeutic agents need to be developed that can overcome the complications of TB. With this purpose, in the present study, 224,205 natural compounds from the ZINC database have been screened against the catalytic site of Mtb proteasome by the computational approach. The best scoring hits, ZINC3875469, ZINC4076131, and ZINC1883067, demonstrated robust interaction with Mtb proteasome with binding energy values of -7.19, -7.95, and -7.21 kcal/mol for the monomer (K-chain) and -8.05, -9.10, and -7.07 kcal/mol for the dimer (both K and L chains) of the beta subunit, which is relatively higher than that of reference compound HT1171 (-5.83 kcal/mol (monomer) and -5.97 kcal/mol (dimer)). In-depth molecular docking of top-scoring compounds with Mtb proteasome reveals that amino acid residues Thr1, Arg19, Ser20, Thr21, Gln22, Gly23, Asn24, Lys33, Gly47, Asp124, Ala126, Trp129, and Ala180 are crucial in binding. Furthermore, a molecular dynamics study showed steady-state interaction of hit compounds with Mtb proteasome. Computational prediction of physicochemical property assessment showed that these hits are non-toxic and possess good drug-likeness properties. This study proposed that these compounds could be utilized as potential inhibitors of Mtb proteasome to combat TB infection. However, there is a need for further bench work experiments for their validation as inhibitors of Mtb proteasome.


Asunto(s)
Antituberculosos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Inhibidores de Proteasoma/farmacología , Dominio Catalítico , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Unión Proteica , Tuberculosis/microbiología
8.
Molecules ; 25(23)2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33271751

RESUMEN

SARS-CoV-2 is a positive-stranded RNA virus that bundles its genomic material as messenger-sense RNA in infectious virions and replicates these genomes through RNA intermediates. Several virus-encoded nonstructural proteins play a key role during the viral life cycle. Endoribonuclease NSP15 is vital for the replication and life cycle of the virus, and is thus considered a compelling druggable target. Here, we performed a combination of multiscoring virtual screening and molecular docking of a library of 1624 natural compounds (Nuclei of Bioassays, Ecophysiology and Biosynthesis of Natural Products (NuBBE) database) on the active sites of NSP15 (PDB:6VWW). After sequential high-throughput screening by LibDock and GOLD, docking optimization by CDOCKER, and final scoring by calculating binding energies, top-ranked compounds NuBBE-1970 and NuBBE-242 were further investigated via an indepth molecular-docking and molecular-dynamics simulation of 60 ns, which revealed that the binding of these two compounds with active site residues of NSP15 was sufficiently strong and stable. The findings strongly suggest that further optimization and clinical investigations of these potent compounds may lead to effective SARS-CoV-2 treatment.


Asunto(s)
Antivirales/farmacología , Endorribonucleasas/química , Ensayos Analíticos de Alto Rendimiento/métodos , Proteínas no Estructurales Virales/química , Antivirales/química , Antivirales/farmacocinética , Dominio Catalítico , Endorribonucleasas/metabolismo , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Ligandos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Proteínas no Estructurales Virales/metabolismo , Tratamiento Farmacológico de COVID-19
9.
Bioinformation ; 16(8): 586-593, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33214746

RESUMEN

Methicillin resistant Staphylococcus aureus infections impose a huge risk to public health in healthcare and community settings worldwide. Therefore, it is of interest to document data on the anti-biogramas and genotypes of isolates from Saudi Arabia. We assessed the antimicrobial susceptibility, determined spa (protein A gene) and analyzed multilocus MLST genotypes, and detected PVL gene in these isolates. We collected 28 clinical MRSA isolates, cultured and determined the minimum inhibitory concentrations of 17 antimicrobial agents using Vitek2 system (BioMerieux, USA) from 3 hospitals in Saudi Arabia during the year 2012. Polymorphic region of the spa and seven housekeeping genes were amplified and sequenced. BioNumerics v.5.1 (Applied Maths) was used for spa typing and MLST. Samples were screened for the presence of PVL and mecA genes using polymerase chain reaction (PCR). Analysis shows that all isolates were susceptible to chloramphenicol, rifampicin, nitrofurantoin, teicoplanin, daptomycin and vancomycin. The T4573/ST22 strains are found to be prevalent in the Saudi Arabia (N=6, 21%). We further noted that three isolates (t363/ST240 strain) were resistant to eight antimicrobial agents. Most of t4573/ST22 strains were PVL positive, resistant to ciprofloxacin and linked to HA-MRSA infections. We document data for the presence of emerging multi drug resistant S. aureus strains carrying the PVL gene circulating within hospitals. This highlights the urgent need for continuous active surveillance and implementation of prevention measures.

10.
AIMS Public Health ; 7(2): 354-362, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32617362

RESUMEN

Cardiovascular disease is a well-known and widely studied disease. Epidemiological studies indicated that the mortality rate due to cardiovascular diseases increases every year. According to the WHO (world health organization) report, cardiovascular disease is one of the most prevalent non-communicable diseases in Saudi Arabia. Moreover, the Ministry of Health, Kingdom of Saudi Arabia, also reported that 42% of the non-communicable disease death is associated with cardiovascular disease in Saudi Arabia. Various reports suggest that heart disease is associated with several risk factors. Moreover, diabetes is one of the high-risk factors. Clinical result suggests a good association between diabetes and cardiovascular complications. In the present work, we focus on some of the important risk factors responsible for heart disease such as weight, blood pressure, age, and diabetes. A set questionnaire, which includes all the parameters associated with cardiovascular disease, was prepared. Data collected from the heart patient's records of different hospitals in Al-Qassim, Saudi Arabia. We applied statistical tools to analyze the data. Our results shows very interactive and significant pattern. We found significant inter-correlation between the different risk factors. In conclusion, the inter-correlation among different risk factors of heart disease is found. It is suggested that both pre and post-heart patients should be more concern about these risk factors. Moreover, this study can be used for further research, and, will increase people awareness regarding their healthy choice.

11.
Cell Mol Biol (Noisy-le-grand) ; 64(4): 46-51, 2018 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-29642988

RESUMEN

Lymphatic filariasis (LF) is a chronic and debilitating disease that affects people in tropical and sub-tropical areas of Asia, Africa, and Western Pacific. It is one of the leading community health problems in some of the endemic districts in India including Hardoi district of Uttar Pradesh. The disease is caused by the parasites Wuchereria bancrofti (W. bancrofti), Brugia malayi (B. malayi) and Brugia timori (B. timori), transmitted by the vector Culex, Anopheles and other mosquitoes. This cross-sectional survey study was carried out in rural areas, where its inhabitants vary in socio-economic status, from low to middle-income class. 12 villages of Hardoi district, Uttar Pradesh, India were included. The aim was to see the impact of age and gender on various clinical forms of LF and in estimating its economic and social implications. 260 LF affected people in different parts of Hardoi district were surveyed. The results revealed that the Mass Drug Administration (MDA) coverage reached more than 90%. The overall Microfilaria rate had been reduced, however the prevalence of elephantiasis increased with the progression of age and was found to be highest among people of >70 years of age, regardless of their gender.


Asunto(s)
Filariasis Linfática/epidemiología , Filariasis Linfática/prevención & control , Enfermedades Endémicas/prevención & control , Administración Masiva de Medicamentos , Adolescente , Adulto , Factores de Edad , Anciano , Albendazol/uso terapéutico , Animales , Anopheles/parasitología , Antiparasitarios/uso terapéutico , Brugia Malayi/efectos de los fármacos , Niño , Estudios Transversales , Culex/parasitología , Femenino , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores Sexuales , Factores Socioeconómicos , Wuchereria bancrofti/efectos de los fármacos
12.
Curr Drug Metab ; 19(9): 798-805, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29512446

RESUMEN

BACKGROUND: Understanding of cervical cancer severity is still an important health issue across the world, especially for developing countries. Cancer or abnormal growth of the cell is one of the major health problems of the world. There are about two hundred types of malignancies reported till date. An updated statistic of all the main types of cancer and pathophysiology of cervical cancer is a significant need for designing the future treatment strategy. OBJECTIVE: In this review, a brief update on cancer, its causes and different types has been discussed along with updated statistics of patient's mortality. A brief overview of cervical cancer and its pathophysiology has been discussed with special emphasis on its causative agent, human papilloma virus (HPV). A brief introduction and update on genetics, molecular pathogenesis and prevalence of HPV and its role in cervical cancer have been added. CONCLUSION: This review delivered an updated status of cervical cancer and provide novel therapeutic approaches for targeting HPV. The detailed molecular and genomic information of the HPV help the researchers to develop more effective and efficacious therapeutic strategies and preventive vaccines that will significantly contribute to the control and anticipation of cervical cancer. Ultimately this may open new vistas to get rid of this deadly disease and may offer significant reduction in the numbers of advanced cervical cancers and deaths from cervical cancer in the affected nations.


Asunto(s)
Infecciones por Papillomavirus/complicaciones , Neoplasias del Cuello Uterino/etiología , Femenino , Genes Supresores de Tumor , Genoma Viral , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/transmisión , Neoplasias del Cuello Uterino/epidemiología
13.
Mol Biosyst ; 13(2): 350-362, 2017 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-27934984

RESUMEN

The nuclear matrix associated protein SMAR1 is sensitive to p53 and acts as a stress inducer as well as a regulator in the p53 regulatory network. Depending on the amount of stress SMAR1 stimulates, it can drive the p53 dynamics in the system to various dynamical states which correspond to various cellular states. The behavior of p53 in these dynamical states is found to be multifractal, due to the mostly long range correlations and large scale fluctuations imparted by stress. This fractal behavior is exhibited in the topological properties of the networks constructed from these dynamical states, and is a signature of self-organization to optimize information flow in the dynamics. The assortativity found in these networks is due to perturbation induced by stress, and indicates that the hubs in the time series play a significant role in stress management. SMAR1 can also regulate apoptosis in the presence of HDAC1, depending on the stress induced by it.


Asunto(s)
Apoptosis/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Algoritmos , Proteínas Portadoras , Daño del ADN , Fractales , Histona Desacetilasa 1/metabolismo , Humanos , Modelos Biológicos , Unión Proteica , Proteína p53 Supresora de Tumor/metabolismo , Flujo de Trabajo
14.
Comput Biol Chem ; 59 Pt B: 55-66, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26375870

RESUMEN

We present the mechanism of interaction of Wnt network module, which is responsible for periodic somitogenesis, with p53 regulatory network, which is one of the main regulators of various cellular functions, and switching of various oscillating states by investigating p53-Wnt model. The variation in Nutlin concentration in p53 regulating network drives the Wnt network module to different states, stabilized, damped and sustain oscillation states, and even to cycle arrest. Similarly, the change in Axin2 concentration in Wnt could able to modulate the p53 dynamics at these states. We then solve the set of coupled ordinary differential equations of the model using quasi steady state approximation. We, further, demonstrate the change of p53 and GSK3 interaction rate, due to hypothetical catalytic reaction or external stimuli, can able to regulate the dynamics of the two network modules, and even can control their dynamics to protect the system from cycle arrest (apoptosis).


Asunto(s)
Redes Reguladoras de Genes , Proteína p53 Supresora de Tumor/metabolismo , Vía de Señalización Wnt , Apoptosis , Proteína Axina/metabolismo , Redes Reguladoras de Genes/genética , Glucógeno Sintasa Quinasa 3/metabolismo , Humanos , Imidazoles/metabolismo , Modelos Biológicos , Piperazinas/metabolismo , Proteína p53 Supresora de Tumor/genética , Vía de Señalización Wnt/genética
15.
PLoS One ; 10(6): e0129620, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26090895

RESUMEN

We study the regulating mechanism of p53 on the properties of cell cycle dynamics in the light of the proposed model of interacting p53 and cell cycle networks via p53. Irradiation (IR) introduce to p53 compel p53 dynamics to suffer different phases, namely oscillating and oscillation death (stabilized) phases. The IR induced p53 dynamics undergo collapse of oscillation with collapse time Δt which depends on IR strength. The stress p53 via IR drive cell cycle molecular species MPF and cyclin dynamics to different states, namely, oscillation death, oscillations of periods, chaotic and sustain oscillation in their bifurcation diagram. We predict that there could be a critical Δtc induced by p53 via IRc, where, if Δt〈Δtc the cell cycle may come back to normal state, otherwise it will go to cell cycle arrest (apoptosis).


Asunto(s)
Ciclo Celular/fisiología , Proteína p53 Supresora de Tumor/metabolismo , Ciclo Celular/efectos de la radiación , Ciclinas/metabolismo , Factor Promotor de Maduración/metabolismo , Modelos Biológicos , Unión Proteica , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Radiación Ionizante
16.
Math Med Biol ; 32(4): 437-56, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25713051

RESUMEN

We study transition of the temporal behaviours of p53 and MDM2 in a stress p53-MDM2-NO regulatory network induced by a bioactive molecule NO (Nitric Oxide). We further study synchronization among a group of identical stress systems arranged in a 3D array with nearest neighbour diffusive coupling. The role of NO and the effect of noise are investigated. In the single system study, we found three distinct types of temporal behaviour of p53, namely oscillation death, damped oscillation and sustained oscillation, depending on the amount of stress induced by NO, indicating how p53 responds to incoming stress. The correlation among coupled systems increases as the value of the coupling constant (ϵ) is increased (γ increases) and becomes constant after a certain value of ϵ. The permutation entropy spectra H(ϵ) for p53 and MDM2 as a function of ϵ are found to be different due to direct and indirect interaction of NO with respective proteins. We find γ versus ϵ for p53 and MDM2 to be similar in a deterministic approach but different in a stochastic approach, and the separation between γ of the respective proteins as a function of ϵ decreases as system size increases. The role of NO is found to be two-fold: stress induced by NO is prominent at small and large values of ϵ but synchrony induced by it dominates in the moderate range of ϵ. Excess stress induces apoptosis.


Asunto(s)
Modelos Biológicos , Óxido Nítrico/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Estrés Fisiológico/fisiología , Proteína p53 Supresora de Tumor/metabolismo , Entropía , Humanos
17.
PLoS One ; 8(2): e52736, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23437037

RESUMEN

We construct a stress p53-Mdm2-p300-HDAC1 regulatory network that is activated and stabilised by two regulatory proteins, p300 and HDAC1. Different activation levels of [Formula: see text] observed due to these regulators during stress condition have been investigated using a deterministic as well as a stochastic approach to understand how the cell responds during stress conditions. We found that these regulators help in adjusting p53 to different conditions as identified by various oscillatory states, namely fixed point oscillations, damped oscillations and sustain oscillations. On assessing the impact of p300 on p53-Mdm2 network we identified three states: first stabilised or normal condition where the impact of p300 is negligible, second an interim region where p53 is activated due to interaction between p53 and p300, and finally the third regime where excess of p300 leads to cell stress condition. Similarly evaluation of HDAC1 on our model led to identification of the above three distinct states. Also we observe that noise in stochastic cellular system helps to reach each oscillatory state quicker than those in deterministic case. The constructed model validated different experimental findings qualitatively.


Asunto(s)
Proteína p300 Asociada a E1A/metabolismo , Histona Desacetilasa 1/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Transducción de Señal , Estrés Fisiológico , Proteína p53 Supresora de Tumor/metabolismo , Humanos , Cinética , Modelos Biológicos , Estabilidad Proteica , Procesos Estocásticos , Factores de Tiempo
18.
Mol Biosyst ; 9(3): 508-21, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23360948

RESUMEN

The integration of calcium and a p53-Mdm2 oscillator model is studied using a deterministic as well as a stochastic approach, to investigate the impact of a calcium wave on single cell dynamics and on the inter-oscillator interaction. The high dose of calcium in the system activates the nitric oxide synthase, synthesizing nitric oxide which then downregulates Mdm2 and influences drastically the p53-Mdm2 network regulation, lifting the system from a normal to a stressed state. The increase in calcium level switches the system to different states, as identified by the different behaviours of the p53 temporal dynamics, i.e. oscillation death to sustain the oscillation state via a mixed state of dampened and oscillation death states. Further increase of the calcium dose in the system switches the system from sustained to oscillation death state again, while an excess of calcium shifts the cell to an apoptotic state. Another important property of the calcium ion is its ability to behave as a synchronizing agent among the interacting systems. The time evolution of the p53 dynamics of the two diffusively coupled systems at stress condition via Ca(2+) shows synchronization between the two systems. The noise contained in the system interestingly helps the system to maintain its stabilized state (normal condition). However, noise has the tendency to destruct the synchronization effect, which means that it tries to restrict the system from external signals to maintain its normal condition. However, at the stress condition, the synchronization rate is found to be faster.


Asunto(s)
Señalización del Calcio , Modelos Biológicos , Proteína p53 Supresora de Tumor/fisiología , Algoritmos , Calcio/fisiología , Simulación por Computador , Humanos , Redes y Vías Metabólicas , Estabilidad Proteica , Proteínas Proto-Oncogénicas c-mdm2/fisiología , Análisis de la Célula Individual , Estrés Fisiológico
19.
Comput Biol Chem ; 41: 10-7, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23131789

RESUMEN

We examine the possibilities of various coupling mechanisms among a group of identical stochastic oscillators via Chemical Langevin formalism where each oscillator is modeled by stochastic model of testosterone (T) releasing pathway. Our results show that the rate of synchrony among the coupled oscillators depends on various parameters namely fluctuating factor, coupling constants [symbol; see text], and interestingly on system size. The results show that synchronization is achieved much faster in classical deterministic system rather than stochastic system. Then we do large scale simulation of such coupled pathways using stochastic simulation algorithm and the detection of synchrony is measured by various order parameters such as synchronization manifolds, phase plots etc and found that the proper synchrony of the oscillators is maintained in different coupling mechanisms and support our theoretical claims. We also found that the coupling constant follows power law behavior with the systems size (V) by [symbol; see text] ~ AV(-γ), where γ=1 and A is a constant. We also examine the phase transition like behavior in all coupling mechanisms that we have considered for simulation. The behavior of the system is also investigated at thermodynamic limit; where V → ∞, molecular population, N → ∞ but N/V → finite, to see the role of noise in information processing and found the destructive role in the rate of synchronization.


Asunto(s)
Modelos Biológicos , Testosterona/química , Testosterona/metabolismo , Algoritmos , Procesos Estocásticos , Termodinámica
20.
Biosystems ; 110(2): 74-83, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23059707

RESUMEN

We have modeled an MTBP-MDM2-p53 regulatory network by integrating p53-MDM2 autoregulatory model (Proctor and Gray, 2008) with the effect of a cellular protein MTBP (MDM2 binding protein) which is allowed to bind with MDM2 (Brady et al., 2005). We study this model to investigate the activation of p53 and MDM2 steady state levels induced by MTBP protein under different stress conditions. Our simulation results in three approaches namely deterministic, Chemical Langevin equation and stochastic simulation of Master equation show a clear transition from damped limit cycle oscillation to fixed point oscillation during a certain time period with constant stress condition in the cell. This transition is the signature of transition of p53 and MDM2 levels from activated state to stabilized steady state levels. We present various phase diagrams to show the transition between unstable and stable states of p53 and MDM2 concentration levels and also their possible relations among critical value of the parameters at which the respective protein level reach stable steady states. In the stochastic approach, the dynamics of the proteins become noise induced process depending on the system size. We found that this noise enhances the stability of the p53 steady state level.


Asunto(s)
Proteínas Portadoras/metabolismo , Redes Reguladoras de Genes , Homeostasis/fisiología , Modelos Biológicos , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Simulación por Computador , Humanos
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