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1.
Cell ; 149(1): 88-100, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22386318

RESUMO

Posttranscriptional regulatory mechanisms superimpose "fine-tuning" control upon "on-off" switches characteristic of gene transcription. We have exploited computational modeling with experimental validation to resolve an anomalous relationship between mRNA expression and protein synthesis. The GAIT (gamma-interferon-activated inhibitor of translation) complex repressed VEGF-A synthesis to a low, constant rate independent of VEGF-A mRNA expression levels. Dynamic model simulations predicted an inhibitory GAIT-element-interacting factor to account for this relationship and led to the identification of a truncated form of glutamyl-prolyl tRNA synthetase (EPRS), a GAIT constituent that mediates binding to target transcripts. The truncated protein, EPRS(N1), shields GAIT-element-bearing transcripts from the inhibitory GAIT complex, thereby dictating a "translational trickle" of GAIT target proteins. EPRS(N1) mRNA is generated by polyadenylation-directed conversion of a Tyr codon in the EPRS-coding sequence to a stop codon (PAY(∗)). Genome-wide analysis revealed multiple candidate PAY(∗) targets, including the authenticated target RRM1, suggesting a general mechanism for production of C terminus-truncated regulatory proteins.


Assuntos
Aminoacil-tRNA Sintetases/genética , Regulação da Expressão Gênica , Genoma Humano , Biossíntese de Proteínas , Sequência de Aminoácidos , Aminoacil-tRNA Sintetases/química , Códon de Terminação , Humanos , Leucócitos Mononucleares/metabolismo , Dados de Sequência Molecular , Complexos Multiproteicos/metabolismo , Poliadenilação , Transcriptoma , Células U937 , Fator A de Crescimento do Endotélio Vascular/genética
2.
Langmuir ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989856

RESUMO

An ensemble of nanosystems can be considered to improve magnetic resonance imaging (MRI) transverse relaxivity. Herein, an interacting superparamagnetic competing structure of an isotropic-anisotropic trimagnetic hybrid nanosystem, γ-Fe2O3@δ-MnO2@NiFe2O4, is considered for MRI relaxivity exploration. The interacting superparamagnetic system reveals fascinating dynamic magnetic behavior, where flower-shaped two-dimensional flakes are decorated over nanoparticles. The hybrid nanosystem exhibits modulated shape anisotropy with spin blocking and energy barrier broadening, which help in achieving faster MR transverse relaxivity. The hierarchical architecture ensemble of the trimagnetic landscape shows effective MR transverse relaxivity with a transverse (r2)/longitudinal (r1) relaxivity of 61.5 and potential cell viability. The competing trimagnetic system with regulated activation energy is found to be the underlying reason for such signal enhancement in MRI contrast efficiency. Hence, this study displays a novel pathway correlating MR transverse relaxivity with dynamic magnetic behavior and competing landscape of hierarchical trimagnetic ensembles.

3.
Langmuir ; 40(3): 1793-1803, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38181379

RESUMO

The potential application of magnetic nanosystems as magnetic resonance imaging (MRI) contrast agents has been thoroughly investigated. This work seeks to attain robust MRI-contrast efficiency by designing an interacting landscape of a bimagnetic ensemble of zinc ferrite nanorods and maghemite nanoparticles, γ-Fe2O3@ZnFe2O4. Because of competing spin clusters and structural anisotropy triggered by isotropic γ-Fe2O3 and anisotropic ZnFe2O4, γ-Fe2O3@ZnFe2O4 undergoes the evolution of cluster spin-glass state as evident from the critical slowing down law. Such interacting γ-Fe2O3@ZnFe2O4 with spin flipping of 1.2 × 10-8 s and energy barrier of 8.2 × 10-14 erg reflects enhanced MRI-contrast signal. Additionally, γ-Fe2O3@ZnFe2O4 is cell-viable to noncancerous HEK 293 cell-line and shows no pro-tumorigenic activity as observed in MDA-MB-231, an extremely aggressive triple-negative breast cancer cell line. As a result, γ-Fe2O3@ZnFe2O4 is a feasible option for an MRI-contrast agent having longitudinal relaxivity, r1, of 0.46 s-1mM-1 and transverse relaxivity, r2, of 15.94 s-1mM-1, together with r2/r1 of 34.65 at 1.41 T up to a modest metal concentration of 0.1 mM. Hence, this study addresses an interacting isotropic/anisotropic framework with faster water proton decay in MR-relaxivity resulting in phantom signal amplification.

4.
Mol Cell Biochem ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951378

RESUMO

Ribosomal proteins (RPs) are constituents of macromolecular machinery, ribosome that translates genetic information into proteins. Besides ribosomal functions, RPs are now getting appreciated for their 'moonlighting'/extra-ribosomal functions modulating many cellular processes. Accumulating evidence suggests that a number of RPs are involved in inflammation. Though acute inflammation is a part of the innate immune response, uncontrolled inflammation is a driving factor for several chronic inflammatory diseases. An in-depth understanding of inflammation regulation has always been valued for the better management of associated diseases. Hence, this review first outlines the common livelihood of RPs and then provides a comprehensive account of five RPs that significantly contribute to the inflammation process. Finally, we discuss the possible therapeutic uses of RPs against chronic inflammatory diseases.

5.
Langmuir ; 38(36): 11087-11098, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36041119

RESUMO

The aim of the work is to explore structure-relaxivity relationship by observing transverse relaxivity enhancement in magnetic resonance imaging (MRI) of differently organized superparamagnetic complex ensembles of zinc ferrite isotropic/anisotropic nanosystems. We observe that superparamagnetic systems show a correlation of MRI-transverse relaxivity, r2/r1, with spatial arrangement of nanoparticles, as well as magnetic easy axes and thermal-energy-dependent anisotropy energy landscape. The presence of highly random/partially aligned easy axes with enhanced anisotropy constant leads to modulation in transverse relaxation. As a result, we achieve highest contrast efficiency in compact ensemble of isotropic nanoparticles and hollow core ensemble. Indeed, core-shell ensemble with combined effect of aligned and randomly oriented easy magnetic axes shows a reduction in MRI contrast efficiency. However, we address a hypothesis for transverse contrast efficiency where we depict the correlation among MRI-transverse contrast efficiency with structural complexity of ensembles, differently arranged primary nanoparticles/magnetic easy axes, anisotropy constant, and collective magnetic behavior. In consequence, we simplify the limitation of quantum mechanical outer-sphere diffusion model of magnetic resonance relaxivity by neglecting the contribution of magnetization and introducing an anisotropy constant contribution with complex structure landscape of easy axes.


Assuntos
Nanopartículas de Magnetita , Anisotropia , Meios de Contraste/química , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Nanopartículas de Magnetita/química
6.
Expert Rev Proteomics ; 18(6): 463-481, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34110968

RESUMO

Background: The snake venom nerve growth factor (NGF)-induced signal transduction mechanism has never been explored.Research design and methods: Homology modeling and molecular dynamic studies of the interaction between Russell's viper venom NGF (RVV-NGFa) and mammalian tropomyosin-receptor kinase A (TrkA) was done by computational analysis. Transcriptomic and quantitative tandem mass spectrometry analyses determined the expression of intracellular genes and proteins, respectively, in RVV-NGFa-treated PC-12 neuronal cells. Small synthetic inhibitors of the signal transduction pathways were used to validate the major signaling cascades of neuritogenesis by RVV-NGFa.Results: A comparative computational analysis predicted the binding of RVV-NGFa, mouse 2.5S-NGF (conventional neurotrophin), and Nn-α-elapitoxin-1 (non-conventional neurotrophin) to different domains of the TrkA receptor in PC-12 cells. The transcriptomic and quantitative proteomic analyses in unison showed differential expressions of common and unique genes and intracellular proteins, respectively, in RVV-NGFa-treated cells compared to control (untreated) mouse 2.5S-NGF and Nn-α-elapitoxin-1-treated PC-12 cells. The RVV-NGFa primarily triggered the mitogen-activated protein kinase-1 (MAPK1) signaling pathway for inducing neuritogenesis; however, 36 pathways of neuritogenesis were uniquely expressed in RVV-NGFa-treated PC-12 cells compared to mouse 2.5S NGF or Nn-α-elapitoxin-1 treated cells.Conclusion: The common and unique intracellular signaling pathways of neuritogenesis by classical and non-classical neurotrophins were identified.


Assuntos
Neoplasias das Glândulas Suprarrenais , Daboia , Feocromocitoma , Animais , Camundongos , Fator de Crescimento Neural , Proteômica , Ratos , Transcriptoma , Venenos de Víboras
7.
Nutr Cancer ; 73(11-12): 2477-2490, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33034216

RESUMO

Medicinal plants offer enormous possibilities in the quest of novel bioactive formulation for cancer therapy. Here, we studied the anticancer efficacy of the extract of edible tuber Amorphophallus paeoniifolius (Dennst.) (APTE) against estrogen positive MCF-7 and triple negative MDA-MB-231 breast cancer cell lines. APTE showed significant cytotoxic activity in both MCF-7 and MDA-MB-231 cells in a dose and time-dependent manner. The effect of APTE on metastatic parameters e.g., migration, adhesion, and invasion in MCF-7 and MDA-MB-231 cells were studied using wound healing, collagen adhesion, and transwell matrigel invasion assays, respectively. APTE significantly reduced migration in both the cell lines, however, its effect on the inhibition of adhesion and invasion was higher in MDA-MB-231 cells. Annexin V-Cy3 staining suggested that APTE induced apoptosis in these cells which was further validated by attenuation of antiapoptotic Bcl-2 and induction of pro-apoptotic Bax, Caspase-7 expression and cleavage of PARP. High resolution-liquid chromatography mass spectroscopy analysis with bioactive ethyl acetate and butanol fractions of APTE detected several compounds with anticancer activities. Overall, the study described the mechanism of anticancer activity of a common edible tuber A. paeoniifolius and contributes to growing list of naturally occurring chemo-preventive strategies.


Assuntos
Amorphophallus , Neoplasias da Mama , Amorphophallus/química , Apoptose , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Células MCF-7 , Extratos Vegetais/química , Extratos Vegetais/farmacologia
8.
J Neurochem ; 155(6): 612-637, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33460153

RESUMO

This is the first report showing unique neuritogenesis potency of Indian Cobra N. naja venom long-chain α-neurotoxin (Nn-α-elapitoxin-1) exhibiting no sequence similarity to conventional nerve growth factor, by high-affinity binding to its tyrosine kinase A (TrkA) receptor of rat pheochromocytoma (PC-12) cells without requiring low-affinity receptor p75NTR. The binding residues between Nn-α-elapitoxin-1 and mammalian TrkA receptor are predicted by in silico analysis. This binding results in a time-dependent internalization of TrkA receptor into the cytoplasm of PC-12 cells. The transcriptomic analysis has demonstrated the differential expression of 445 genes; 38 and 32 genes are up-regulated and down-regulated, respectively in the PC-12 cells post-treatment with Nn-α-elapitoxin-1. Global proteomic analysis in concurrence with transcriptomic data has also demonstrated that in addition to expression of a large number of common intracellular proteins in the control and Nn-α-elapitoxin-1-treated PC-12 cells, the latter cells also showed the expression of uniquely up-regulated and down-regulated intracellular proteins involved in diverse cellular functions. Altogether, the data from transcriptomics, proteomics, and inhibition of downstream signaling pathways by specific inhibitors, and the immunoblot analysis of major regulators of signaling pathways of neuritogenesis unambiguously demonstrate that, similar to mouse 2.5S-nerve growth factor, the activation of mitogen activated protein kinase/extracellular signal-regulated kinase is the major signaling pathway for neuritogenesis by Nn-α-elapitoxin-1. Nonetheless, fibroblast growth factor signaling and heterotrimeric G-protein signaling pathways were found to be uniquely expressed in Nn-α-elapitoxin-1-treated PC-12 cells and not in mouse 2.5S-nerve growth factor -treated cells. The TrkA binding region of Nn-α-elapitoxin-1 may be developed as a peptide-based drug prototype for the treatment of major central neurodegenerative diseases. Read the Editorial Highlight for this article on page 599.


Assuntos
Venenos Elapídicos/metabolismo , Venenos Elapídicos/farmacologia , Proteômica/métodos , Receptor trkA/metabolismo , Transcriptoma/fisiologia , Sequência de Aminoácidos , Animais , Venenos Elapídicos/genética , Células HEK293 , Humanos , Células MCF-7 , Naja , Células PC12 , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Estrutura Secundária de Proteína , Ratos , Receptor trkA/genética , Transcriptoma/efeitos dos fármacos
9.
Inflamm Res ; 69(11): 1143-1156, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32852592

RESUMO

OBJECTIVE: IL-6-induced STAT3 activation is associated with various chronic inflammatory diseases. In this study, we investigated the anti-STAT3 mechanism of the dietary polyphenol, biochanin A (BCA), in IL-6-treated macrophages. METHODS: The effect of BCA on STAT3 and p38 MAPK was analyzed by immunoblot. The localization of both these transcription factors was determined by immunofluorescence and fractionation studies. The impact on DNA-binding activity of STAT3 was studied by luciferase assay. To understand which of the isoforms of p38 MAPK was responsible for BCA-mediated regulation of STAT3, overexpression of the proteins, site-directed mutagenesis, pull-down assays and computational analysis were performed. Finally, adhesion-migration assays and semi-quantitative PCR were employed to understand the biological effects of BCA-mediated regulation of STAT3. RESULTS: BCA prevented STAT3 phosphorylation (Tyr705) and increased p38 MAPK phosphorylation (Thr180/Tyr182) in IL-6-stimulated differentiated macrophages. This opposing modulatory effect of BCA was not observed in cells treated with other stress-inducing stimuli that activate p38 MAPK. BCA abrogated IL-6-induced nuclear translocation of phospho-STAT3 and its transcriptional activity, while increasing the cellular abundance of phospho-p38 MAPK. BCA-induced phosphorylation of p38δ, but not α, ß, or γ was responsible for impeding IL-6-induced STAT3 phosphorylation. Interestingly, interaction with phospho-p38δ masked the Tyr705 residue of STAT3, preventing its phosphorylation. BCA significantly reduced STAT3-dependent expression of icam-1 and mcp-1 diminishing IL-6-mediated monocyte adhesion and migration. CONCLUSION: This differential regulation of STAT3 and p38 MAPK in macrophages establishes a novel anti-inflammatory mechanism of BCA which could be important for the prevention of IL-6-associated chronic inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Genisteína/farmacologia , Interleucina-6/farmacologia , Macrófagos/efeitos dos fármacos , Proteína Quinase 13 Ativada por Mitógeno/metabolismo , Fator de Transcrição STAT3/metabolismo , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/fisiologia , Macrófagos/fisiologia , Proteína Quinase 13 Ativada por Mitógeno/genética , Fosforilação/efeitos dos fármacos , Células THP-1
10.
Water Sci Technol ; 77(3-4): 638-646, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29431708

RESUMO

Biochar obtained through the pyrolysis of Pongamia glabra seed cover (PGSC) at 550 °C with a heating rate of 40 °C/min was characterized and its ability to adsorb the dyes Methylene blue (MB) and Rhodamine B (RB) from aqueous solutions was investigated. The effect of pH, temperature and initial concentration of the dyes on adsorption behavior were investigated. The equilibrium sorption data were analyzed by using Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich (D-R) isotherms. Equilibrium data were well fitted for D-R isotherm in case of MB and Langmuir isotherm in case of RB dyes. The kinetics of dye adsorption on PGSC biochar was well described by applying pseudo-second-order rate equations. The surface of adsorbent before and after the removal of dyes was characterized by using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis. The study suggested that PGSC biochar could be used as a highly efficient adsorbent for the removal of synthetic dyes.


Assuntos
Carvão Vegetal/química , Corantes/química , Azul de Metileno/química , Pongamia , Rodaminas/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Sementes , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
11.
J Biochem Mol Toxicol ; 31(10)2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28608598

RESUMO

The present study describes the purification and partial characterization of a basic anticoagulant PLA2 enzyme named as Rv(i) PLA2 from the venom of Indian Daboia russelii. The molecular mass of the protein was found to be 13,659.65 Da, and peptide mass fingerprinting revealed that it belongs to group II PLA2 family. The peptide sequence showed similarity to uncharacterized basic PLA2 enzyme having an accession no. of P86368 reported from Sri Lankan D. russelii. Rv(i) PLA2 exhibited strong phospholipase A2 and anticoagulant activity. It also induced expression of COX-2 and TNF-α mRNA in a dose-dependent manner in phorbol 12-myristate 13-acetate differentiated THP-1 cells, which play a crucial role during inflammation. Chemical modification of His residue in Rv(i) PLA2 with p-bromophenacyl bromide abolished the enzymatic, anticoagulant, and inflammatory activities. The result indicates that the catalytic site of Rv(i) PLA2 might play a vital role in inducing inflammation at the bite site during D. russelii envenomation.


Assuntos
Anticoagulantes/toxicidade , Daboia , Fosfolipases A2 do Grupo II , Mediadores da Inflamação/metabolismo , Venenos de Víboras/enzimologia , Animais , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Linhagem Celular Tumoral , Fosfolipases A2 do Grupo II/química , Fosfolipases A2 do Grupo II/isolamento & purificação , Fosfolipases A2 do Grupo II/toxicidade , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Venenos de Víboras/química
12.
Mol Cell ; 35(2): 164-80, 2009 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-19647514

RESUMO

Glutamyl-prolyl tRNA synthetase (EPRS) is a component of the heterotetrameric gamma-interferon-activated inhibitor of translation (GAIT) complex that binds 3'UTR GAIT elements in multiple interferon-gamma (IFN-gamma)-inducible mRNAs and suppresses their translation. Here, we elucidate the specific EPRS phosphorylation events that regulate GAIT-mediated gene silencing. IFN-gamma induces sequential phosphorylation of Ser(886) and Ser(999) in the noncatalytic linker connecting the synthetase cores. Phosphorylation of both sites is essential for EPRS release from the parent tRNA multisynthetase complex. Ser(886) phosphorylation is required for the interaction of NSAP1, which blocks EPRS binding to target mRNAs. The same phosphorylation event induces subsequent binding of ribosomal protein L13a and GAPDH and restores mRNA binding. Finally, Ser(999) phosphorylation directs the formation of a functional GAIT complex that binds initiation factor eIF4G and represses translation. Thus, two-site phosphorylation provides structural and functional pliability to EPRS and choreographs the repertoire of activities that regulates inflammatory gene expression.


Assuntos
Aminoacil-tRNA Sintetases/fisiologia , Inativação Gênica/fisiologia , Biossíntese de Proteínas/fisiologia , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/metabolismo , Células Cultivadas , Fator de Iniciação Eucariótico 4G/metabolismo , Humanos , Interferon gama/metabolismo , Interferon gama/fisiologia , Modelos Genéticos , Fosforilação , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , RNA Mensageiro/fisiologia , Proteínas Ribossômicas/metabolismo , Serina/metabolismo
13.
Genomics ; 107(6): 239-47, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27133569

RESUMO

The objective of the study was to gain molecular insights into the progression of atherosclerosis in Apob(tm2Sgy)Ldlr(tm1Her) mice, using transcriptome profiles. Weighted gene co network analysis (WGCNA) and time course analysis using limma were used to study disease progression from 0 to 20weeks. Five co-expression modules were identified by WGCNA using the expression values of 2153 genes. Genes associated with autophagy, endoplasmic reticulum stress, inflammation and lipid metabolism were differentially expressed at early stages of atherosclerosis. Time course analysis highlighted activation of inflammatory gene signaling at 4weeks, cell proliferation and calcification at 8weeks, amyloid like structures and oxidative stress at 14weeks and enhanced production of inflammatory cytokines at 20weeks. Our results suggest that maximum gene perturbations occur during early atherosclerosis which could be the danger signals associated with subclinical disease. Understanding these genes and associated pathways can help in improvement of diagnostic and therapeutic targets for atherosclerosis.


Assuntos
Apolipoproteínas B/genética , Aterosclerose/genética , Inflamação/genética , Receptores de LDL/efeitos dos fármacos , Animais , Aterosclerose/patologia , Autofagia/genética , Modelos Animais de Doenças , Progressão da Doença , Estresse do Retículo Endoplasmático/genética , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Inflamação/patologia , Metabolismo dos Lipídeos/genética , Camundongos , Camundongos Knockout , Estresse Oxidativo/genética
14.
Water Sci Technol ; 75(5-6): 1138-1147, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28272042

RESUMO

Fresh water streams contaminated with synthetic dye-containing effluents pose a threat to aquatic and human life either by preventing aquatic photosynthesis or by entering into the food chain. Adsorptive removal of such dyes with potent biosorbents is an important technique to reduce bioaccumulation and biomagnifications of the dyes in human life. We report use of betel nut (BN) husk and banana peel (BP), two most abundant ligno-cellulosic wastes, as efficient adsorbents for the removal of the basic dye methylene blue (MB). The adsorption by BN and BP was consistently high over wide ranges of pH and temperature, suggesting their dye removal potential in diverse conditions. Physico-chemical studies, e.g. scanning electron microscopy and Fourier transform-infrared spectroscopy studies, revealed changes in surface topology and functional moieties of BN and BP post adsorption, implying dye interaction with the biomass surface. The dye adsorption in both cases followed pseudo-second-order kinetics. While adsorption of MB by BN was better fitted with the Temkin isotherm model, adsorption with BP followed both Langmuir and Freundlich isotherm models. Our studies concluded that both adsorbents efficiently remove MB from its aqueous solution with BP proved to be marginally superior to BN.


Assuntos
Agricultura , Azul de Metileno/isolamento & purificação , Temperatura , Resíduos , Adsorção , Areca/ultraestrutura , Biomassa , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Modelos Teóricos , Musa/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água
15.
J Cardiovasc Pharmacol ; 68(1): 89-96, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27385185

RESUMO

Cardiovascular diseases (CVDs) are the commonest cause of global mortality and morbidity. Atherosclerosis, the fundamental pathological manifestation of CVDs, is a complex process and is poorly managed both in terms of preventive and therapeutic intervention. Aberrant lipid metabolism and chronic inflammation play critical roles in the development of atherosclerosis. These processes can be targeted for effective management of the disease. Although managing lipid metabolism is in the forefront of current therapeutic approaches, controlling inflammation may also prove to be crucial for an efficient treatment regimen of the disease. Flavonoids, the plant-derived polyphenols, are known for their antiinflammatory properties. This review discusses the possible antiatherogenic role of 3 flavonoids, namely, chrysin, quercetin, and luteolin primarily known for their antiinflammatory properties.


Assuntos
Anti-Inflamatórios/administração & dosagem , Aterosclerose/prevenção & controle , Dieta Saudável , Flavonoides/administração & dosagem , Inflamação/prevenção & controle , Luteolina/administração & dosagem , Quercetina/administração & dosagem , Animais , Anti-Inflamatórios/farmacocinética , Aterosclerose/metabolismo , Aterosclerose/patologia , Aterosclerose/fisiopatologia , Disponibilidade Biológica , Flavonoides/farmacocinética , Humanos , Inflamação/metabolismo , Inflamação/patologia , Inflamação/fisiopatologia , Mediadores da Inflamação/metabolismo , Absorção Intestinal , Metabolismo dos Lipídeos/efeitos dos fármacos , Luteolina/farmacocinética , Quercetina/farmacocinética
16.
Mol Cell ; 32(3): 371-82, 2008 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-18995835

RESUMO

Phosphorylation of ribosomal protein L13a is essential for translational repression of inflammatory genes by the interferon (IFN)-gamma-activated inhibitor of translation (GAIT) complex. Here we show that IFN-gamma activates a kinase cascade in which death-associated protein kinase-1 (DAPK) activates zipper-interacting protein kinase (ZIPK), culminating in L13a phosphorylation on Ser(77), L13a release from the ribosome, and translational silencing of GAIT element-bearing target mRNAs. Remarkably, both kinase mRNAs contain functional 3'UTR GAIT elements, and thus the same inhibitory pathway activated by the kinases is co-opted to suppress their expression. Inhibition of DAPK and ZIPK facilitates cell restoration to the basal state and allows renewed induction of GAIT target transcripts by repeated stimulation. Thus, the DAPK-ZIPK-L13a axis forms a unique regulatory module that first represses, then repermits inflammatory gene expression. We propose that the module presents an important checkpoint in the macrophage "resolution of inflammation" program, and that pathway defects may contribute to chronic inflammatory disorders.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Inflamação/genética , MAP Quinase Quinase Quinases/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação , Regulação da Expressão Gênica , Humanos , Inflamação/enzimologia , Inflamação/fisiopatologia , Fragmentos de Peptídeos/química , Fosforilação , Plasmídeos , RNA Mensageiro/genética , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Ribossomos/genética , Ribossomos/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transfecção , Células U937
17.
Trends Biochem Sci ; 34(7): 324-31, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19535251

RESUMO

Functionally related genes are coregulated by specific RNA-protein interactions that direct transcript-selective translational control. In myeloid cells, interferon (IFN)-gamma induces formation of the heterotetrameric, IFN-gamma-activated inhibitor of translation (GAIT) complex comprising glutamyl-prolyl tRNA synthetase (EPRS), NS1-associated protein 1 (NSAP1), ribosomal protein L13a and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). This complex binds defined 3' untranslated region elements within a family of inflammatory mRNAs and suppresses their translation. IFN-gamma-dependent phosphorylation, and consequent release of EPRS and L13a from the tRNA multisynthetase complex and 60S ribosomal subunit, respectively, regulates GAIT complex assembly. EPRS recognizes and binds target mRNAs, NSAP1 negatively regulates RNA binding, and L13a inhibits translation initiation by binding eukaryotic initiation factor 4G. Repression of a post-transcriptional regulon by the GAIT system might contribute to the resolution of chronic inflammation.


Assuntos
Inflamação/genética , Interferon gama/metabolismo , Processamento Pós-Transcricional do RNA/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Regiões 3' não Traduzidas/metabolismo , Aminoacil-tRNA Sintetases/metabolismo , Animais , Fator de Iniciação Eucariótico 4G/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , MicroRNAs/metabolismo , Células Mieloides/metabolismo , Proteínas Ribossômicas/metabolismo
18.
Heliyon ; 10(1): e23616, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38187223

RESUMO

Scrub typhus is a vector-borne infectious disease caused by Orientia tsutsugamushi and it is reportedly associated with up to 20 % of hospitalized cases of febrile illnesses. The major challenge of vaccine development is the lack of identified antigens that can induce both heterotypic and homotypic immunity including the production of antibodies, cytotoxic T lymphocyte, and helper T lymphocytes. We employed a comprehensive immunoinformatic prediction algorithm to identify immunogenic epitopes of the 56-kDa type-specific cell membrane surface antigen and surface cell antigen A of O. tsutsugamushi to select potential candidates for developing vaccines and diagnostic assays. We identified 35 linear and 29 continuous immunogenic B-cell epitopes and 51 and 27 strong-binding T-cell epitopes of major histocompatibility complex class I and class II molecules, respectively, in the conserved and variable regions of the 56-kDa type-specific surface antigen. The predicted B- and T-cell epitopes were used to develop immunogenic multi-epitope candidate vaccines and showed to elicit a broad-range of immune protection. A stable interactions between the multi-epitope vaccines and the host fibronectin protein were observed using docking and simulation methods. Molecular dynamics simulation studies demonstrated that the multi-epitope vaccine constructs and fibronectin docked models were stable during simulation time. Furthermore, the multi-epitope vaccine exhibited properties such as antigenicity, non-allergenicity and ability to induce interferon gamma production and had strong associations with their respective human leukocyte antigen alleles of world-wide population coverage. A correlation of immune simulations and the in-silico predicted immunogenic potential of multi-epitope vaccines implicate for further investigations to accelerate designing of epitope-based vaccine candidates and chimeric antigens for development of serological diagnostic assays for scrub typhus.

19.
Transl Oncol ; 21: 101433, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35462210

RESUMO

While the anti-inflammatory activities of Eriodictyol, a plant-derived flavonoid is well-known, reports on its anti-cancer efficacy and selective cytotoxicity in cancer cells are still emerging. However, little is known regarding its mechanism of selective anti-cancer activities. Here, we show the mechanism of selective cytotoxicity of Eriodictyol towards cancer cells compared to normal cells. Investigation reveals that Eriodictyol significantly upregulates TNFR1 expression in tumor cells (HeLa and SK-RC-45) while sparing the normal cells (HEK, NKE and WI-38), which display negligible TNFR1 expression, irrespective of the absence or presence of Eriodictyol. Further investigation of the molecular events reveal that Eriodictyol induces apoptosis through expression of the pro-apoptotic DISC components leading to activation of the caspase cascade. In addition, CRISPR-Cas9 mediated knockout of TNFR1 completely blocks apoptosis in HeLa cells in response to Eriodictyol, confirming that Eriodictyol induced cancer cell apoptosis is indeed TNFR1-dependent. Finally, in vivo data demonstrates that Eriodictyol not only impedes tumor growth and progression, but also inhibits metastasis in mice implanted with 4T1 breast cancer cells. Thus, our study has identified Eriodictyol as a compound with high selectivity towards cancer cells through TNFR1 and suggests that it can be further explored for its prospect in cancer therapeutics.

20.
Front Public Health ; 10: 956422, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36249255

RESUMO

Background: Home visitation has emerged as an effective model to provide high-quality care during pregnancy, childbirth, and post-natal period and improve the health outcomes of mother- new born dyad. This 3600 assessment documented the constraints faced by the community health workers (known as the Accredited Social Health Activists, ASHAs) to accomplish home visitation and deliver quality services in a poor-performing district and co-created the strategies to overcome these using a nexus planning approach. Methods: The study was conducted in the Raisen district of Madhya Pradesh, India. The grounded theory approach was applied for data collection and analysis using in-depth interviews, and focus group discussions with stakeholders representing from health system (including the ASHAs) and the community (rural population). A key group of diverse stakeholders were convened to utilize the nexus planning five domain framework (social-cultural, educational, organizational, economic, and physical) to prioritize the challenges and co-create solutions for improving the home visitation program performance and quality. The nexus framework provides a systemic lens for evaluating the success of the ASHAs home visitation program. Results: The societal (caste and economic discrimination), and personal (domestic responsibilities and cultural constraints of working in the village milieu) issues emerged as the key constraints for completing home visits. The programmatic gaps in imparting technical knowledge and skills, mentoring system, communication abilities, and unsatisfactory remuneration system were the other barriers to the credibility of the services. The nexus planning framework emphasized that each of the above factors/domains is intertwined and affects or depends on each other for home-based maternal and newborn care services delivered with quality through the ASHAs. Conclusion: The home visitation program services, quality and impact can be enhanced by addressing the social-cultural, organizational, educational, economic, and physical nexus domains with concurrent efforts for skill and confidence enhancement of the ASHAs and their credibility.


Assuntos
Agentes Comunitários de Saúde , Visita Domiciliar , Feminino , Humanos , Lactente , Recém-Nascido , Mães , Gravidez , Pesquisa Qualitativa , População Rural
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