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1.
Life Sci ; 352: 122857, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914305

RESUMO

AIM: AMPK can be considered as an important target molecule for cancer for its unique ability to directly recognize cellular energy status. The main aim of this study is to explore the role of different AMPK activators in managing cancer cell aggressiveness and to understand the mechanistic details behind the process. MAIN METHODS: First, we explored the AMPK expression pattern and its significance in different subtypes of lung cancer by accessing the TCGA data sets for LUNG, LUAD and LUSC patients and then established the correlation between AMPK expression pattern and overall survival of lung cancer patients using Kaplan-Meire plot. We further carried out several cell-based assays by employing different wet lab techniques including RT-PCR, Western Blot, proliferation, migration and invasion assays to fulfil the aim of the study. KEY FINDINGS: SIGNIFICANCE: This study identifies the importance of AMPK activators as a repurposing agent for combating lung and colon cancer cell aggressiveness. It also suggests SRT-1720 as a potent repurposing agent for cancer treatment especially in NSCLC patients where a point mutation is present in LKB1.

2.
Langmuir ; 39(31): 10947-10964, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37501125

RESUMO

A series of pyrrolidine-based Pd(II) complexes, [Pd(AEP)Cl2] (C-1), [Pd(AEP)(OH2)2]2+(C-2), [Pd(AEP)(L-cys)]+ (C-3), [Pd(AEP)(N-ac-L-cys)] (C-4), [Pd(AEP)(GSH)] (C-5), and [Pd(AEP)(DL-meth)]2+ (C-6) (where, AEP = 1-(2-aminoethyl)pyrrolidine, L-cys = l-cysteine, N-ac-L-cys = N-acetyl-l-cysteine, GSH = glutathione, and DL-meth = dl-methionine), as anticancer drug candidates have been synthesized and characterized. The DNA binding property of the complexes was executed by gel electrophoresis and spectrophotometric and viscometric methods, and their interaction with BSA was also investigated by various spectroscopic methodologies. The binding activity of the Pd(II) complexes with DNA and BSA were assessed to evaluate their binding mode and binding constants. Molecular docking was performed to correlate with the experimental results on the interaction of the complexes with DNA and BSA. The changes in the microenvironmental and structural properties of BSA are monitored by a synchronous and 3D fluorescence study. The structural properties were evaluated by DFT and TD-DFT studies. The anticarcinogenic activity of the Pd(II) complexes was assessed by PASS prediction software to corroborate with the experimental results of the anticancer activity of the complexes. The ROS generation in cancer cell lines has been investigated, and the cell death mechanism through apoptosis was confirmed by measuring the protein expression. All these complexes have excellent anticancer activity compared to ancillary ligands. The cancer cell line (HCT116) shows almost similar or better cell inhibition activity when treated with the Pd(II) complexes compared to cisplatin, whereas the adverse effect is minimum on a normal cell (NKE). Both the Pd(II) and Pt(II) complexes carrying the same ligands reveal almost similar antiproliferative activity.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Humanos , Simulação de Acoplamento Molecular , Paládio/farmacologia , Paládio/química , Ligantes , DNA/química , Linhagem Celular , Antineoplásicos/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Soroalbumina Bovina/química
4.
Heliyon ; 9(2): e13620, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36873140

RESUMO

In the quest of recognizing hazardous nitro-aromatic compounds in water, two pyridine-functionalized Schiff-base chemosensors, DMP ((E)-N-(3,4-dimethoxybenzylidene)(pyridin-2-yl)methanamine)) and MP (4-((E)-((pyridin-2-yl)methylimino)methyl)-2-ethoxyphenol) have been synthesized to detect mutagenic 2,4,6-Trinitrophenol (TNP) in soil, water as well as cellular matrices by producing turn-off emission responses as a combined consequence of PET and RET processes. Several experimental analyses including ESI-MS, FT-IR, photoluminescence, 1H NMR titration, and the theoretical calculations ascertained the formation and sensing efficacies of the chemosensors. The analytical substantiations revealed that structural variation of the chemosensors played a significant role in improving the sensing efficiency, which would certainly be worthwhile in developing small molecular TNP sensors. The present work depicted that the electron density within the MP framework was more than that of DMP due to the intentional incorporation of -OEt and -OH groups. As a result, MP represented a strong interaction mode towards the electron-deficient TNP with a detection limit of 39 µM.

5.
Free Radic Biol Med ; 195: 309-328, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36592660

RESUMO

This study depicted the effect of IL-13 and 13(S)HpODE (the endogenous product during IL-13 activation) in the process of cancer cell apoptosis. We examined the role of both IL-13 and 13(S)HpODE in mediating apoptotic pathway in three different in vitro cellular models namely A549 lung cancer, HCT116 colorectal cancer and CCF52 GBM cells. Our data showed that IL-13 promotes apoptosis of A549 lung carcinoma cells through the involvement of 15-LO, PPARγ and MAO-A. Our observations demonstrated that IL-13/13(S)HpODE stimulate MAO-A-mediated intracellular ROS production and p53 as well as p21 induction which play a crucial role in IL-13-stimulated A549 cell apoptosis. We further showed that 13(S)HpODE promotes apoptosis of HCT116 and CCF52 cells through the up-regulation of p53 and p21 expression. Our data delineated that IL-13 stimulates p53 and p21 induction which is mediated through 15-LO and MAO-A in A549 cells. In addition, we observed that PPARγ plays a vital role in apoptosis as well as in p53 and p21 expression in A549 cells in the presence of IL-13. We validated our observations in case of an in vivo colon cancer tumorigenic study using syngeneic mice model and demonstrated that 13(S)HpODE significantly reduces solid tumor growth through the activation of apoptosis. These data thus confirmed that IL-13 > 15-LO>13(S)HpODE > PPARγ>MAO-A > ROS > p53>p21 axis has a major contribution in regulating cancer cell apoptosis and further identified 13(S)HpODE as a potential chemo-preventive agent which can improve the efficacy of cancer treatment as a combination compound.


Assuntos
Apoptose , Interleucina-13 , Neoplasias Pulmonares , Proteína Supressora de Tumor p53 , Animais , Camundongos , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Interleucina-13/farmacologia , Neoplasias Pulmonares/patologia , Monoaminoxidase/genética , Monoaminoxidase/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Humanos , Células A549
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 287(Pt 1): 122059, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36410178

RESUMO

The complex [Pt(AEP)Cl2]; C-1 (where, AEP = 1-(2-Aminoethyl) pyrrolidine) and its hydrolyzed diaqua form cis-[Pt(AEP)(H2O)2]2+; C-2 were synthesized for their bioactivity and in vitro kinetic study with bioactive thiol group (-SH) containing ligands (like; L- cysteine and N-ac-L- cysteine) for their biological importance for 'drug reservoir' activity. The Thermal Gravimetric Analysis (TGA) was executed to confirm about the weight loss due to coordinated water molecules at high temperature range. At pH 4.0, the substitution behavior of C-2 with the thiols was studied in pseudo-first order reaction condition. The interaction mechanism of thiols with complex C-2 to their corresponding thiol substituted C-3 [Pt(AEP)(L-cys)] and C-4 [Pt(AEP)(N-ac-L-cys)] (where L-cys = L-cysteine and N-ac-L-cys = N-ac-L- cysteine) were proposed from their thermodynamical activation parameters (ΔH≠ and ΔS≠), which were obtained from Eyring equation. DNA and BSA binding activity of the complexes C-1 to C-4 were investigated by gel electrophoresis technique, spectroscopic titration and viscosity methods. The binding activity of the complexes with DNA and BSA was evaluated using a theoretical approach molecular docking study. The drug-like nature of the complexes is supported by the prediction of activity spectra for substance (PASS) from 2D structure of the Pt(II) complexes. Structural optimization, HOMO-LUMO energy calculation, Molecular electrostatic potential surface, NBO and TD-DFT calculation were executed by using density functional theory (DFT) with Gaussian 09 software package to pre-assessment of biological activity of the complexes. DFT-based descriptors were determined from the HOMO-LUMA energy to be related with the ability of binding affinity of Pt(II) complexes towards DNA and BSA to the formation of their corresponding adducts. The anticancer property of the design complexes were examined on HCT116 (colorectal carcinoma) cancer cell lines and as well as human normal cell NKE (Normal Kidney Epithelial) and compared with the recognised anticancer drug cisplatin. The Reactive Oxygen Species (ROS) production was assessed by DCFDA assay in presence of the Pt(II) complexes.


Assuntos
Cisteína , DNA , Humanos , Simulação de Acoplamento Molecular , Cinética , Pirrolidinas , Compostos de Sulfidrila
7.
Bone Rep ; 17: 101642, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36504506

RESUMO

Aromatase (CYP19A1) is the only enzyme known to catalyse the conversion of androgen to estrogen. Aromatase deficiency occurs due to mutation in CYP19A1gene which has an autosomal recessive inheritance pattern. It leads to decrease in estrogen synthesis and delayed epiphyseal closure, eunuchoid habitus and osteopenia. We are presenting here, a 24 years old male, with history of progressive increase in height and knock knees. X-ray showed open wrist and knee epiphysis. The serum testosterone level was normal and serum estradiol level was undetectable. Semen analysis showed azoospermia. Clinical exome sequencing gave two novel mutations in CYP19A1. The first variant was a novel single nucleotide deletion of thiamine at 570th base of the cDNA (c.570delT) of CYP19A1 gene. The second variant detected was again a novel one in the same gene in Exon 5 corresponding 344th base of the cDNA (c344G>A) resulting in a missense mutation of 115th arginine to glutamine in the protein. Sanger sequencing showed that the later mutation was inherited from the father. The patient was started on oral estradiol valerate for epiphyseal closure to prevent further increase in height. Only 15 mutations have been reported in the aromatase gene in males till date, our report of these novel mutations will be an add-on to the literature.

8.
iScience ; 25(9): 105021, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36111254

RESUMO

The usual treatment for anemia and especially for anemia of inflammation (also called anemia of chronic disease) is supportive care with the target of improving the lifestyle of the patients. There is no effective medication to date for proper management. As the inflammation, erythropoiesis, and oxidative stress are the major concerns in this case, it inspired us to use a nano-erythropoietin stimulating agent (nano-ESA) made up of a nano-complex of manganese and citrate (Mn-citrate nano-complex), which has been hypothesized to have excellent antioxidant and anti-inflammatory mechanisms. Single oral dose of the nano-ESA efficiently prevented the onset of anemia as well as led to recovery from anemia in our phenylhydrazine (PHz)-intoxicated C57BL/6J mice model of anemia without any toxicological side effects. These preliminary findings may pave the way for an affordable and safe clinical use of the nano-ESA as a rapid recovery medication of anemia, especially anemia of inflammation.

9.
Front Chem ; 10: 978668, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118312

RESUMO

Enzyme function can be altered via modification of its amino acid residues, side chains and large-scale domain modifications. Herein, we have addressed the role of residue modification in catalytic activity and molecular recognition of an enzyme alpha-chymotrypsin (CHT) in presence of a covalent cross-linker formalin. Enzyme assay reveals reduced catalytic activity upon increased formalin concentration. Polarization gated anisotropy studies of a fluorophore 8-Anilino-1-naphthalenesulfonic acid (ANS) in CHT show a dip rise pattern in presence of formalin which is consistent with the generation of multiple ANS binding sites in the enzyme owing to modifications of its local amino acid residues. Molecular docking study on amino acid residue modifications in CHT also indicate towards the formation of multiple ANS binding site. The docking model also predicted no change in binding behavior for the substrate Ala-Ala-Phe-7-amido-4-methylcoumarin (AMC) at the active site upon formalin induced amino acid cross-linking.

10.
Bioorg Chem ; 128: 106093, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35985157

RESUMO

Herein, we report the synthesis and characterisation of a series of Pd(II) complexes: Pd(TEEDA)Cl2, C-1; [Pd(TEEDA)(OH2)2](NO3)2, C-2; [Pd(TEEDA)(l-cys)](NO3)2, C-3; [Pd(TEEDA)(NALC)], C-4; [Pd(TEEDA)(Meth)](NO3)2, C-5; and [Pd(TEEDA)(GSH)], C-6 (where TEEDA = N,N,N'-Triethylenediamine, l-cys = l-cysteine, NALC = N-acetyl-l-cysteine, Meth = dl-methionine and GSH = glutathione). UV-Vis spectroscopic characterisation was supported by TD-DFT theoretical simulation using Gaussian09 software. Different reactivity parameters were calculated from the energy difference between HOMO and LUMO of the complexes by DFT. The bonding mode of the labile ligands was confirmed by NBO analysis. Interaction of the complexes with DNA has been observed by gel electrophoresis experiment. DNA binding nature as well as binding constants of the complexes were measured with UV-Vis and fluorescence spectroscopic method. The binding nature of the complexes with DNA was confirmed by viscometric titration. Interaction of the complexes with BSA was investigated by UV-Vis and fluorescence titration method. Cytotoxic activity of the Pd(II) complexes was evaluated on A549 (lung carcinoma epithelial cells), HCT116(Colorectal Carcinoma) and HEK293 (Human embryonic kidney cells) cell lines. The ROS generation in the presence of the complexes was tested both on cancer cell lines A549 and HCT116 as well as human normal cell HEK293.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Antineoplásicos/química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , DNA/química , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Paládio/química , Paládio/farmacologia , Soroalbumina Bovina/química
11.
Prostaglandins Other Lipid Mediat ; 160: 106637, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35341977

RESUMO

The oxygenation of polyunsaturated fatty acids such as arachidonic and linoleic acid through enzymes like lipoxygenases (LOXs) are common and often leads to the production of various bioactive lipids that are important both in acute inflammation and its resolution and thus in disease progression. Amongst the several isoforms of LOX that are expressed in mammals, 15-lipoxygenase (15-LOX) has shown to be crucial in the context of inflammation. Moreover, being expressed in cells of the immune system, as well as in epithelial cells; the enzyme has been shown to crosstalk with a number of important signalling pathways. Mounting evidences from recent reports suggest that 15-LOX has anti-cancer activities which are dependent or independent of its metabolites, and is executed through several downstream pathways like cGMP, PPAR, p53, p21 and NAG-1. However, it is still unclear whether the up-regulation of 15-LOX is associated with cancer cell apoptosis. Monoamine oxidase A (MAO-A), on the other hand, is a mitochondrial flavoenzyme which is believed to be involved in the pathogenesis of atherosclerosis and inflammation and in many other neurological disorders. MAO-A has also been reported as a potential therapeutic target in different types of cancers like prostate cancer, lung cancer etc. In this review, we discussed about the role of fatty acids and their lipid mediators in cancer cell apoptosis. Here we particularly focused on the contribution of oxidative enzymes like 15-LOX and MAO-A in mediating apoptosis in lung cancer cell after fatty acid induction.


Assuntos
Ácidos Graxos , Neoplasias Pulmonares , Animais , Apoptose , Inflamação , Mamíferos , Monoaminoxidase
12.
ChemMedChem ; 16(24): 3739-3749, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34550644

RESUMO

Functionalized nanoparticles reveal new frontiers in therapeutics and diagnostics, simultaneously referred to as theranostics. Functionalization of an inorganic nanoparticle (NP) with an organic ligand determines the interaction of the functionalized NPs with various cellular components, leading to the desired therapeutic effect, while diminishing adverse side effects. Apart from the therapeutic effect of the nanoparticles, other physical properties of the organic-inorganic complex (nanohybrid) including fluorescence, X-ray or MRI contrast offer diagnosis of the anomalous target cell. In this study we functionalized Mn3 O4 NPs with organic citrate (C-Mn3 O4 ) and folic acid (FA-Mn3 O4 ) ligands and investigated their antimicrobial activities using Staphylococcus hominis as a model bacteria, which can be remediated through their membrane rupture. While high-resolution transmission microscopy (HR-TEM), XRD, DLS, absorbance and fluorescence spectroscopy were used for structural characterisation of the functionalised NPs, zeta potential measurements and temperature-dependent reactive oxygen speices (ROS) generation reveal their drug action. We used high-end density functional theory (DFT) calculations to rationalise the specificity of the drug action of the NPs. Picosecond-resolved FRET studies confirm the enhanced affinity of FA-Mn3 O4 to the bacteria relative to C-Mn3 O4 , leading to enhanced antimicrobial activity. We have shown that the functionalised nanoparticles offer significant X-ray contrast in in-vitro studies, indicating the FA-Mn3 O4 NPs to be a potential theranostic agent against bacterial infection.


Assuntos
Antibacterianos/farmacologia , Teoria da Densidade Funcional , Staphylococcus hominis/efeitos dos fármacos , Antibacterianos/química , Ácido Cítrico/química , Ácido Cítrico/farmacologia , Relação Dose-Resposta a Droga , Difusão Dinâmica da Luz , Ácido Fólico/química , Ácido Fólico/farmacologia , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Nanopartículas/química , Óxidos/química , Óxidos/farmacologia , Espectrometria de Fluorescência , Relação Estrutura-Atividade , Nanomedicina Teranóstica , Difração de Raios X
13.
Commun Biol ; 4(1): 1013, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446827

RESUMO

Targeting reactive oxygen species (ROS) while maintaining cellular redox signaling is crucial in the development of redox medicine as the origin of several prevailing diseases including chronic kidney disease (CKD) is linked to ROS imbalance and associated mitochondrial dysfunction. Here, we have shown that a potential nanomedicine comprising of Mn3O4 nanoparticles duly functionalized with biocompatible ligand citrate (C-Mn3O4 NPs) can maintain cellular redox balance in an animal model of oxidative injury. We developed a cisplatin-induced CKD model in C57BL/6j mice with severe mitochondrial dysfunction and oxidative distress leading to the pathogenesis. Four weeks of treatment with C-Mn3O4 NPs restored renal function, preserved normal kidney architecture, ameliorated overexpression of pro-inflammatory cytokines, and arrested glomerulosclerosis and interstitial fibrosis. A detailed study involving human embryonic kidney (HEK 293) cells and isolated mitochondria from experimental animals revealed that the molecular mechanism behind the pharmacological action of the nanomedicine involves protection of structural and functional integrity of mitochondria from oxidative damage, subsequent reduction in intracellular ROS, and maintenance of cellular redox homeostasis. To the best of our knowledge, such studies that efficiently treated a multifaceted disease like CKD using a biocompatible redox nanomedicine are sparse in the literature. Successful clinical translation of this nanomedicine may open a new avenue in redox-mediated therapeutics of several other diseases (e.g., diabetic nephropathy, neurodegeneration, and cardiovascular disease) where oxidative distress plays a central role in pathogenesis.


Assuntos
Mitocôndrias/fisiologia , Nanomedicina , Espécies Reativas de Oxigênio/administração & dosagem , Insuficiência Renal Crônica/terapia , Animais , Feminino , Masculino , Camundongos , Oxirredução
14.
ACS Biomater Sci Eng ; 7(6): 2475-2484, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34060316

RESUMO

Precise control of intracellular redox status, i.e., maintenance of the physiological level of reactive oxygen species (ROS) for mediating normal cellular functions (oxidative eustress) while evading the excess ROS stress (distress), is central to the concept of redox medicine. In this regard, engineered nanoparticles with unique ROS generation, transition, and depletion functions have the potential to be the choice of redox therapeutics. However, it is always challenging to estimate whether ROS-induced intracellular events are beneficial or deleterious to the cell. Here, we propose the concept of redox buffering capacity as a therapeutic index of engineered nanomaterials. As a steady redox state is maintained for normal functioning cells, we hypothesize that the ability of a nanomaterial to preserve this homeostatic condition will dictate its therapeutic efficacy. Additionally, the redox buffering capacity is expected to provide information about the nanoparticle toxicity. Here, using citrate-functionalized trimanganese tetroxide nanoparticles (C-Mn3O4 NPs) as a model nanosystem, we explored its redox buffering capacity in erythrocytes. Furthermore, we went on to study the chronic toxic effect (if any) of this nanomaterial in the animal model to co-relate with the experimentally estimated redox buffering capacity. This study could function as a framework for assessing the capability of a nanomaterial as redox medicine (whether maintains eustress or damages by creating distress), thus orienting its application and safety for clinical use.


Assuntos
Nanopartículas , Nanoestruturas , Animais , Nanoestruturas/toxicidade , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio
15.
Adv Healthc Mater ; 10(7): e2001736, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33326181

RESUMO

The potentiality of nano-enzymes in therapeutic use has directed contemporary research to develop a substitute for natural enzymes, which are suffering from several disadvantages including low stability, high cost, and difficulty in storage. However, inherent toxicity, inefficiency in the physiological milieu, and incompatibility to function in cellular enzyme networks limit the therapeutic use of nanozymes in living systems. Here, it is shown that citrate functionalized manganese-based biocompatible nanoscale material (C-Mn3 O4 NP) efficiently mimics glutathione peroxidase (GPx) enzyme in the physiological milieu and easily incorporates into the cellular multienzyme cascade for H2 O2 scavenging. A detailed computational study reveals the mechanism of the nanozyme action. The in vivo therapeutic efficacy of C-Mn3 O4 nanozyme is further established in a preclinical animal model of Huntington's disease (HD), a prevalent progressive neurodegenerative disorder, which has no effective medication to date. Management of HD in preclinical animal trial using a biocompatible (non-toxic) nanozyme as a part of the metabolic network may uncover a new paradigm in nanozyme based therapeutic strategy.


Assuntos
Antioxidantes , Manganês , Animais , Materiais Biocompatíveis
16.
Soft Matter ; 16(12): 3050-3062, 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32133476

RESUMO

Enzymes are dynamical macromolecules and their conformation can be altered via local fluctuations of side chains, large scale loop and even domain motions which are intimately linked to their function. Herein, we have addressed the role of dynamic flexibility in the catalytic activity of a thermostable enzyme almond beta-glucosidase (BGL). Optical spectroscopy and classical molecular dynamics (MD) simulation were employed to study the thermal stability, catalytic activity and dynamical flexibility of the enzyme. An enzyme assay reveals high thermal stability and optimum catalytic activity at 333 K. Polarization-gated fluorescence anisotropy measurements employing 8-anilino-1-napthelenesulfonic acid (ANS) have indicated increasing flexibility of the enzyme with an increase in temperature. A study of the atomic 3D structure of the enzyme shows the presence of four loop regions (LRs) strategically placed over the catalytic barrel as a lid. MD simulations have indicated that the flexibility of BGL increases concurrently with temperature through different fluctuating characteristics of the enzyme's LRs. Principal Component Analysis (PCA) and the Steered Molecular Dynamics (SMD) simulation manifest the gatekeeper role of the four LRs through their dynamic fluctuations surrounding the active site which controls the catalytic activity of BGL.


Assuntos
Prunus dulcis/enzimologia , beta-Glucosidase/química , Domínio Catalítico , Estabilidade Enzimática , Simulação de Dinâmica Molecular , Conformação Proteica , Estrutura Secundária de Proteína , Prunus dulcis/química , Temperatura , Trifolium/química , Trifolium/enzimologia
17.
ChemMedChem ; 15(5): 420-429, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-31828971

RESUMO

Human exposure to heavy metals can cause a variety of life-threatening disorders, affecting almost every organ of the body, including the nervous, circulatory, cardiac, excretory, and hepatic systems. The presence of heavy metal (cause) and induced oxidative stress (effect) are both responsible for the observed toxic effects. The conventional and effective way to combat heavy metal overload diseases is through use of metal chelators. However, they possess several side effects and most importantly they fail to manage the entire causality. In this study, we introduce citrate-functionalized Mn3 O4 nanoparticles (C-Mn3 O4 NPs) as an efficient chelating agent for treatment of heavy metal overload diseases. By means of UV/Vis absorbance and steady-state fluorescence spectroscopic techniques we investigated the efficacy of the NPs in chelation of a model heavy metal, lead (Pb). We also explored the retention of antioxidant properties of the Pb-chelated C-Mn3 O4 NPs using a UV/Vis-assisted DPPH assay. Through CD spectroscopic studies we established that the NPs can reverse the Pb-induced structural modifications of biological macromolecules. We also studied the in vivo efficacy of NPs in Pb-intoxicated C57BL/6j mice. The NPs were not only able to mobilize the Pb from various organs through chelation, but also saved the organs from oxidative damage. Thus, the C-Mn3 O4 NPs could be an effective nanotherapeutic agent for complete reversal of heavy-metal-induced toxicity through chelation of the heavy metal and healing of the associated oxidative stress.


Assuntos
Quelantes/farmacologia , Chumbo/toxicidade , Compostos de Manganês/farmacologia , Nanopartículas/química , Nitratos/antagonistas & inibidores , Nitratos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Óxidos/farmacologia , Animais , Compostos de Bifenilo/antagonistas & inibidores , Quelantes/química , Dicroísmo Circular , Feminino , Injeções Intraperitoneais , Chumbo/administração & dosagem , Masculino , Compostos de Manganês/química , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Nitratos/administração & dosagem , Óxidos/química , Picratos/antagonistas & inibidores , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
18.
Trans Indian Natl Acad Eng ; 5(3): 509-518, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-38624452

RESUMO

With 6.93M confirmed cases of COVID-19 worldwide, making individuals aware of their sanitary health and ongoing pandemic remains the only way to prevent the spread of this virus. Wearing masks is an important step in this prevention. Hence, there is a need for monitoring if people are wearing masks or not. Closed circuit television (CCTV) cameras endowed with computer vision function by embedded systems, have become popular in a wide range of applications, and can be used in this case for real time monitoring of people wearing masks or not. In this paper, we propose to model this task of monitoring as a special case of object detection. However, real-time scene parsing through object detection running on edge devices is very challenging, due to limited memory and computing power of embedded devices. To deal with these challenges, we used a few popular object detection algorithms such as YOLOv3, YOLOv3Tiny, SSD and Faster R-CNN and evaluated them on Moxa3K benchmark dataset. The results obtained from these evaluations help us to determine methods that are more efficient, faster, and thus are more suitable for real-time object detection specialized for this task.

19.
J Biol Chem ; 293(36): 14040-14064, 2018 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-30021838

RESUMO

Monoamine oxidase A (MAO-A) is a mitochondrial flavoenzyme implicated in the pathogenesis of atherosclerosis and inflammation and also in many neurological disorders. MAO-A also has been reported as a potential therapeutic target in prostate cancer. However, the regulatory mechanisms controlling cytokine-induced MAO-A expression in immune or cancer cells remain to be identified. Here, we show that MAO-A expression is co-induced with 15-lipoxygenase (15-LO) in interleukin 13 (IL-13)-activated primary human monocytes and A549 non-small cell lung carcinoma cells. We present evidence that MAO-A gene expression and activity are regulated by signal transducer and activator of transcription 1, 3, and 6 (STAT1, STAT3, and STAT6), early growth response 1 (EGR1), and cAMP-responsive element-binding protein (CREB), the same transcription factors that control IL-13-dependent 15-LO expression. We further established that in both primary monocytes and in A549 cells, IL-13-stimulated MAO-A expression, activity, and function are directly governed by 15-LO. In contrast, IL-13-driven expression and activity of MAO-A was 15-LO-independent in U937 promonocytic cells. Furthermore, we demonstrate that the 15-LO-dependent transcriptional regulation of MAO-A in response to IL-13 stimulation in monocytes and in A549 cells is mediated by peroxisome proliferator-activated receptor γ (PPARγ) and that signal transducer and activator of transcription 6 (STAT6) plays a crucial role in facilitating the transcriptional activity of PPARγ. We further report that the IL-13-STAT6-15-LO-PPARγ axis is critical for MAO-A expression, activity, and function, including migration and reactive oxygen species generation. Altogether, these results have major implications for the resolution of inflammation and indicate that MAO-A may promote metastatic potential in lung cancer cells.


Assuntos
Interleucina-13/fisiologia , Monoaminoxidase/metabolismo , Monócitos/metabolismo , Células A549 , Araquidonato 15-Lipoxigenase/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Inflamação , Neoplasias Pulmonares/patologia , Monoaminoxidase/fisiologia , Metástase Neoplásica , PPAR gama/metabolismo , Fator de Transcrição STAT6/metabolismo , Células U937
20.
J Environ Sci (China) ; 67: 136-144, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29778145

RESUMO

To use stabilized nanoparticles (NPs) in water as disinfectants over a very long period, the amount of coating agent (for NP stabilization) needs to be optimized. To this end, silver nanoparticles (Ag-NPs) with two different coating densities of tri-sodium citrate (12.05 and 46.17molecules/nm2, respectively), yet of very similar particle size (29 and 27 nm, respectively) were synthesized. Both sets of citrate capped NPs were then separately impregnated on plasma treated activated carbon (AC), with similar Ag loading of 0.8 and 0.82wt.%, respectively. On passing contaminated water (containing 104 CFU Escherichia coli/mL of water) through a continuous flow-column packed with Ag/AC, zero cell concentration was achieved in 22 and 39 min, with Ag-NPs (impregnated on AC, named as Ag/AC) having lower and higher coating density, respectively. Therefore, even on ensuring similar Ag-NP size and loading, there is a significant difference in antibacterial performance based on citrate coating density in Ag/AC. This is observed in lower coating density case, due to both: (i) higher Ag+ ion release from Ag-NP and (ii) stronger binding of individual Ag-NPs on AC. The latter ensures that, Ag-NP does not detach from the AC surface for a long duration. TGA-DSC shows that Ag-NPs with a low coating density bind to AC with 4.55 times higher adsorption energy, compared to Ag/AC with a high coating density, implying stronger binding. Therefore, coating density is an important parameter for achieving higher antibacterial efficacy, translating into a faster decontamination rate in experiments, over a long period of flow-column operation.


Assuntos
Antibacterianos/química , Nanopartículas Metálicas/química , Prata/química , Adsorção , Antibacterianos/toxicidade , Carvão Vegetal , Ácido Cítrico/química , Desinfetantes , Desinfecção/métodos , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Prata/toxicidade , Purificação da Água/métodos
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