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1.
J Cell Physiol ; 238(6): 1226-1236, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120832

RESUMO

The perisinusoidal hepatic stellate cells (HSCs) have been investigated extensively for their role as the major fibrogenic cells during chronic liver injury. HSCs also produce numerous cytokines, chemokines, and growth mediators, and express cell adhesion molecules constitutively and in response to stimulants such as endotoxin (lipopolysaccharide). With this property and by interacting with resident and recruited immune and inflammatory cells, HSCs regulate hepatic immune homeostasis, inflammation, and acute injury. Indeed, experiments with HSC-depleted animal models and cocultures have provided evidence for the prominent role of HSCs in the initiation and progression of inflammation and acute liver damage due to various toxic agents. Thus HSCs and/or mediators derived thereof during acute liver damage may be considered as potential therapeutic targets.


Assuntos
Hepatopatias , Fígado , Animais , Fígado/metabolismo , Citocinas/metabolismo , Células Estreladas do Fígado/metabolismo , Hepatopatias/metabolismo , Inflamação/patologia , Cirrose Hepática/patologia
2.
Am J Pathol ; 192(3): 518-535, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34954210

RESUMO

Acetaminophen (APAP)-induced liver injury is influenced by inflammatory Gram-negative bacterial endotoxin [lipopolysaccharide (LPS)], mechanisms of which are not completely understood. Because LPS-stimulated perisinusoidal hepatic stellate cells (HSCs) produce cytokines that affect survival of hepatocytes, this study investigated their role in APAP-induced liver injury. Fed (nonstarved) rats were administered 5 mg/kg LPS or phosphate-buffered saline (PBS) vehicle, followed by 200 mg/kg APAP or PBS an hour later, and euthanized at 6 hours. Control rats received PBS at both time points. Both LPS and APAP caused mild hepatocyte injury (apoptosis), as assessed by histopathology, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining, and caspase-3 activation. The liver injury was augmented in rats administered LPS + APAP, in association with increased nuclear translocation of interferon-regulatory factor-1 (IRF1). In vitro, APAP augmented LPS/HSC-conditioned medium-induced inhibition of DNA and protein synthesis, apoptosis, and nuclear IRF1 in hepatocytes. LPS-stimulated HSCs produced interferon-ß (IFN-ß), and LPS/HSC + APAP-induced hepatocyte apoptosis was inhibited by anti-IFN-ß antibody. Finally, HSC-depleted mice produced significantly lower IFN-ß and tumor necrosis factor-α, exhibited less oxidative stress, and were protected from excessive injury due to high APAP dose (600 mg/kg), as well as LPS (5 mg/kg overnight) followed by APAP. In co-culture with or without LPS, HSCs increased expression of proinflammatory cytokines by Kupffer cells. These results suggest that HSCs play a critical role in APAP-induced liver injury without or with LPS preconditioning, and it involves INF-ß-IRF1 signaling.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Acetaminofen/metabolismo , Acetaminofen/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Citocinas/metabolismo , Endotoxinas/metabolismo , Endotoxinas/toxicidade , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Lipopolissacarídeos/toxicidade , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ratos
3.
J Assoc Physicians India ; 71(8): 11-12, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37651243

RESUMO

BACKGROUND: Chronic obstructive lung disease (COPD) has been characterized as a smoker's disease, which has resulted in the usual exclusion of never-smokers from COPD studies. It is now recognized that never-smokers account for nearly one-fourth of all COPD cases, and thus airflow limitation in never-smokers needs further evaluation. Our study aims to elucidate the clinical and physiological aspects of COPD in nonsmokers and to compare smokers and nonsmokers with COPD. MATERIALS AND METHODS: A total of 200 naïve sequential patients with COPD were recruited. The severity of airflow limitation in COPD patients was defined as per Global Initiative for COPD (GOLD) 2019 criteria, and the severity of breathlessness was assessed by the modified Medical Research Council (MRC) dyspnea scale. Data was collected using a patient pro forma, including risk factors for COPD and detailed clinical history. Phenotypic differences along with biomass exposure between never-smokers and smokers were analyzed. RESULTS: Compared to smokers, never-smokers presented at a younger age (55.69 ± 11.5 years; p < 0.001), with a longer duration of dyspnea (5.05 ± 4.96 vs 7.35 ± 6.98 years, p < 0.01). Chest radiographs revealed hyperinflation in a higher number of smokers as compared to never-smokers (82.9 vs 64.6%, p < 0.05). On spirometry evaluation, smokers were found to have significantly poorer lung function [forced expiratory volume in first second (FEV1) 40.36 ± 17.76%; forced vital capacity (FVC): 58.16 ± 17.02%] as compared to never-smokers (FEV1: 47.1 ± 16.47%; FVC: 67.38 ± 17.02%) with p < 0.05. With respect to severity at presentation, most (45.8%) never-smokers presented with stage 2 COPD as compared to the majority of smokers (46.7%) who presented with stage 3 COPD (p-value of <0.05). Absolute eosinophil count (AEC) and eosinophil proportion in total leucocyte count (TLC) was significantly higher in never-smokers as compared to the smokers (232 ± 204.2 vs 309 ± 238.8, p < 0.05). Risk factor analysis showed mean biomass exposure index was significantly higher in never-smokers as compared to smokers (56.02 vs 6.28; p-value of <0.001). CONCLUSION: Compared to smokers, COPD in never-smokers presents at a younger age, with a longer duration of dyspnea and higher eosinophil count. Biomass exposure is one of the major contributors to etiologies for COPD in nonsmokers.


Assuntos
não Fumantes , Doença Pulmonar Obstrutiva Crônica , Humanos , Dispneia/etiologia , Fenótipo , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Fumantes , Estudos Prospectivos
4.
Hepatology ; 72(5): 1586-1604, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32031683

RESUMO

BACKGROUND AND AIMS: The augmenter of liver regeneration (ALR) protein is critical for lipid homeostasis and mitochondrial function. We investigated high-fat/high-carbohydrate (HF/HC) diet-induced nonalcoholic fatty liver disease (NAFLD) in wild-type (WT), hepatocyte-specific ALR-knockout (ALR-H-KO), and ALR-heterozygous (ALR-H-HET) mice. ALR was measured in serum of human nonalcoholic steatohepatitis (NASH) and NASH-induced cirrhosis (serum and liver). APPROACH AND RESULTS: HF/HC feeding decreased ALR expression in all groups of mice. The otherwise normal ALR-H-HET mice gained more weight and steatosis than WT mice when challenged metabolically with the HF/HC diet; ALR-H-KO mice gained the least weight and had the least steatosis. These findings were consistent with correspondingly increased triglycerides and cholesterol and altered expression of carnitine palmitoyltransferase 1a, sterol regulatory element-binding protein, acetyl coenzyme A carboxylase, and fatty acid synthase. All HF/HC-fed mice developed insulin resistance, the magnitude being lower in ALR-H-KO mice. HF/HC-fed ALR-H-HET mice were more resistant to glucose challenge than WT or ALR-H-KO mice. The frequency of tumor necrosis factor alpha-producing, interleukin 6 (IL6)-producing, and IL17-producing cells was greater in ALR-H-KO than ALR-H-HET and lowest in WT mice. HF/HC feeding did not increase their number in ALR-H-KO mice, and the increase in ALR-H-HET was greater than that in WT mice except for IL17 cells. Cluster of differentiation 25-positive (CD25+ ) forkhead box P3-positive CD4+ regulatory T-cell frequency was lower in ALR-H-HET than WT mice and further reduced in ALR-H-KO mice; HF/HC reduced regulatory T-cell frequency only in WT mice. HF/HC-fed ALR-H-HET, but not WT, mice developed fibrosis; and ALR-H-KO mice progressed to cirrhosis. White adipose tissue of HF/HC-fed ALR-deficient mice developed strong inflammation, indicating bidirectional interactions with the liver. Hepatic and serum ALR levels were significantly reduced in patients with NASH-cirrhosis. Serum ALR was also significantly lower in patients with NASH. CONCLUSIONS: Hepatic ALR deficiency may be a critical predisposing factor for aggressive NAFLD progression.


Assuntos
Cirrose Hepática/metabolismo , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/deficiência , Adulto , Idoso , Animais , Biópsia , Colesterol/sangue , Colesterol/metabolismo , Dieta da Carga de Carboidratos/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Hepatectomia , Heterozigoto , Humanos , Resistência à Insulina , Fígado/cirurgia , Cirrose Hepática/sangue , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Regeneração Hepática , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/sangue , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Triglicerídeos/sangue , Triglicerídeos/metabolismo
5.
FASEB J ; 33(3): 3825-3840, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30540918

RESUMO

Levels of augmenter of liver regeneration (ALR), a multifunctional protein, are reduced in steatohepatitis. ALR depletion from ALR flox/flox/Alb-Cre [ALR-L-knockout (KO)] mouse causes robust steatosis and apoptosis of hepatocytes, and pericellular fibrosis between 1 and 2 wk postbirth. Steatosis regresses by 4 wk upon reappearance of ALR-expressing hepatocytes. We investigated mechanisms of ALR depletion-induced steatosis. ALR-L-KO mice (1-, 2-, and 4 wk old) and Adeno-Cre-transfected ALR flox/flox hepatocytes were used for in vivo and in vitro studies. ALR depletion from hepatocytes in vivo downregulated peroxisome proliferator-activated receptor (PPAR)-α, carnitine palmitoyl transferase I (CPT1)a, peroxisomal membrane protein 70 (PMP70) (modest down-regulation), and acyl-CoA oxidase 1 (ACOX1). The markedly up-regulated (20X) novel microRNA-540 (miR-540) was identified to target PPARα, PMP70, ACOX1, and CPT1a. ALR depletion from primary hepatocytes increased oxidative stress, miR-540 expression, and steatosis and down-regulated PPARα, ACOX1, PMP70, and CPT1a expression. Anti-miR-540 mitigated ALR depletion-induced steatosis and prevented loss of PPARα, ACOX1, PMP70, and CPT1a expression. Antioxidant N-acetylcysteine and recombinant ALR (rALR) both inhibited ALR depletion-induced miR-540 expression and lipid accumulation in hepatocytes. Finally, treatment of ALR-L-KO mice with rALR between 1 and 2 wk prevented miR-540 expression, and arrested steatosis and fibrosis. We conclude that ALR deficiency-mediated oxidative stress induces generation of miR-540, which promotes steatosis by dysregulating peroxisomal and mitochondrial lipid homeostasis.-Kumar, S., Rani, R., Karns, R., Gandhi, C. R. Augmenter of liver regeneration protein deficiency promotes hepatic steatosis by inducing oxidative stress and microRNA-540 expression.


Assuntos
Fígado Gorduroso/genética , Regeneração Hepática/genética , MicroRNAs/genética , Deficiência de Proteína/genética , Animais , Apoptose/genética , Retículo Endoplasmático/genética , Feminino , Hepatócitos/patologia , Humanos , Fígado/patologia , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Estresse Oxidativo/genética , PPAR alfa/genética , Regulação para Cima/genética
6.
J Biol Chem ; 293(48): 18466-18476, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30348900

RESUMO

Mice depleted of hepatic stellate cells (HSCs) are protected from concanavalin A (ConA)-induced liver injury that is mediated by the activation of interferon regulatory factor 1 (IRF1). The aim of this study was to determine the mechanisms of ConA-mediated signaling and synthesis/release of mediators by HSCs that damage hepatocytes. Primary cultures of wildtype (WT) and IRF1-knockout (KO) HSCs and hepatocytes were used, and ConA-induced liver damage in interferon (IFN)αß receptor-deficient (IFNαßR-KO) mice was determined. Specific binding of ConA to HSCs induced rapid activation of JAK2 and STAT1. ConA-induced expression of IRF1, IFNß, tumor necrosis factor α, and CXCL1 was abrogated by selective inhibition of JAK2 and STAT1. Despite activating JAK2/STAT1, ConA failed to stimulate expression of inflammatory cytokines in HSCs from IRF1-KO mice. ConA-conditioned WT-HSC medium caused activation of JNK and caspase 3, and apoptosis of hepatocytes from WT but not from IRF1-KO or IFNαßR-KO mice. Conversely, ConA-conditioned medium of IRF1-KO HSCs failed to cause apoptosis of WT or IRF1-KO hepatocytes. IFNαßR-KO mice were protected from ConA-induced liver damage, and ConA-induced hepatic expression of IRF1 and pro-inflammatory cytokines and chemokines, and infiltration of neutrophils were significantly lower in IFNαßR-KO than in WT mice. These results demonstrate distinct roles of IRF1 in hepatic inflammation (HSCs) and injury (hepatocytes) and can be an important target for intervention in acute liver injury.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Concanavalina A/farmacologia , Citocinas/biossíntese , Células Estreladas do Fígado/efeitos dos fármacos , Fator Regulador 1 de Interferon/fisiologia , Animais , Células Cultivadas , Meios de Cultivo Condicionados , Citocinas/metabolismo , Células Estreladas do Fígado/metabolismo , Fator Regulador 1 de Interferon/genética , Interferon gama/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor de Interferon alfa e beta/genética , Transdução de Sinais , Superóxido Dismutase-1/metabolismo
7.
Analyst ; 145(1): 83-90, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31710323

RESUMO

The labelling and imaging of mitochondria and nucleolus have attracted great attention because of the involvement of these cellular organelles in critical cellular activities. Therefore, a large number of mitochondria- or nucleolus-labelling probes have been developed throughout the world. However, in the current study, we successfully developed two pyrazole-based, copper-linked triphenylphosphine-coupled emissive metallo-complexes (C1 and C2) for the simultaneous visualization of mitochondria and nucleolus in a single run. These complexes were very inexpensive and could be synthesized by a simple one-pot multicomponent reaction scheme. The complexes were very specific, and only a small concentration of 5 µM was found to be sufficient to probe both the organelles efficiently. Additionally, even under a shorter incubation period (half hour), the fluorescence intensity from the cells was appreciable. Also, both the compounds were found to be photostable when torched with 10% of a 100 mW laser for up to 10 min. All these results indicate that both the complexes may contribute towards the future development of cell imaging tools. To the best of our knowledge, this is the first report on the development of multifunctional live cell imaging tools for simultaneous mitochondria and nucleolus imaging and within the shortest incubation time of about 30 minutes.


Assuntos
Nucléolo Celular/metabolismo , Complexos de Coordenação/química , Corantes Fluorescentes/química , Mitocôndrias/metabolismo , Compostos Organofosforados/química , Pirazóis/química , Complexos de Coordenação/síntese química , Complexos de Coordenação/efeitos da radiação , Cobre/química , Cobre/efeitos da radiação , Teoria da Densidade Funcional , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Células HeLa , Humanos , Lasers , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Modelos Químicos , Compostos Organofosforados/síntese química , Compostos Organofosforados/efeitos da radiação , Pirazóis/síntese química , Pirazóis/efeitos da radiação , Raios Ultravioleta
8.
Am J Pathol ; 187(9): 2008-2019, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28710903

RESUMO

Concanavalin A (ConA) causes immune cell-mediated liver damage, but the contribution of resident nonparenchymal cells (NPCs) is also evident. Hepatic stellate cells (HSCs) induce hepatic inflammation and immunological reactions; we therefore investigated their role in ConA-induced liver injury. ConA was administered i.v. to control or HSC-depleted mice; hepatic histopathology and cytokines/chemokines were determined after 6 hours. In vitro, effects of ConA-conditioned HSC medium on hepatocytes were determined. ConA induced inflammation, sinusoidal congestion, and extensive midzonal hepatocyte death in control mice, which were strongly minimized in HSC-depleted mice. CD4 and natural killer T cells and neutrophils were markedly reduced in ConA-treated HSC-depleted mice compared with control mice. The increase in cytokines/chemokines of hepatic injury was much higher in ConA-treated control mice than in HSC-depleted mice. ConA-treated HSCs showed increased expression of interferon-ß, tumor necrosis factor-α, and CXCL1, induced oxidative stress in hepatocytes, and caused hepatocyte apoptosis. ConA induced nuclear translocation of interferon-regulatory factor-1 (IRF1) in hepatocytes in vivo, and ConA/HSC induced a similar effect in cultured hepatocytes. IRF1-knockout mice were resistant to ConA-induced liver damage, and anti-interferon ß antibody mitigated ConA/HSC-induced injury. In HSC-NPC co-culture, ConA-induced expression of inflammatory cytokines/chemokines was significantly augmented compared with NPCs alone. HSCs play an essential role in ConA-induced liver injury directly via the interferon-ß/IRF1 axis, and by modulating properties of NPCs.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/patologia , Concanavalina A/toxicidade , Células Estreladas do Fígado/patologia , Fígado/patologia , Animais , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Quimiocinas/metabolismo , Citocinas/metabolismo , Células Estreladas do Fígado/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos
9.
Bioprocess Biosyst Eng ; 41(7): 917-929, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29564535

RESUMO

Direct measurement of cell biomass is difficult in a solid-state fermentation (SSF) process involving filamentous fungi since the mycelium and the solid substrate are often inseparable. However, respiratory data are rich in information for real-time monitoring of microbial biomass production. In this regard, a correlation was obtained between oxygen uptake rate (OUR) and biomass concentration (X) of Rhizopus oryzae MTCC 1987, during phytase production, in an intermittently mixed novel SSF bioreactor. To obtain the correlation, various models describing sigmoidal growth were tested, namely the logistic, Gompertz, Stannard, and Schnute models. Regression analysis of experimental results, at different operating conditions of inlet air flow rate and relative humidity suggested that OUR and X were correlated well by the logistic model (R2 > 0.90). To corroborate the use of respiratory data for on-line measurement of metabolic activity, OUR was related to metabolic heat generation rate (Rq), and the logistic model was found to satisfactorily correlate Rq and X as well. The model parameter, YQ/X, when substituted into a heat transfer design equation, along with the values of other parameters and operating variables, gave reliable estimates of bed temperature. The correlations developed in the present study, between respiratory activity and biomass concentration may be extended on to other SSF processes for further validation and real-time monitoring of cell biomass and bed temperature.


Assuntos
Biomassa , Reatores Biológicos , Modelos Biológicos , Consumo de Oxigênio , Oxigênio/metabolismo , Rhizopus/crescimento & desenvolvimento
10.
Eur J Immunol ; 44(2): 431-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24214631

RESUMO

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. FoxP3 have been shown to have important implications in various diseases. The present study describes the mechanism of action of FoxP3 in CD4⁺CD25⁺ T cells derived from leprosy patients. Increased molecular interactions of FoxP3 with histone deacetylases 7/9 in the nucleus of CD4⁺CD25⁺ T cells derived from borderline lepromatous leprosy/lepromatous leprosy (BL/LL) patients were found to be responsible for FoxP3-driven immune suppression activities during the progression of leprosy. Further, downregulation of CTLA-4 and CD25 genes in siFoxP3-treated PBMCs derived from BL/LL patients elucidated the transcription-activating nature of FoxP3. This observation was supported by direct binding of FoxP3 to the promoter region of the CTLA-4 and CD25 genes, and FoxP3's molecular interaction with histone acetyl transferases. The study also revealed that the increased expression of miR155 in CD4⁺CD25⁺ cells from BL/LL governs the competitive fitness of these cells. Again, reduced Annexin V & propidium iodide staining and Nur77 expression, and concomitantly increased Ki-67 positivity suggested that CD4⁺CD25⁺ cells derived from BL/LL patients are more competitively fit than those from borderline tuberculoid leprosy/tuberculoid leprosy and healthy controls. Taken together, the study shows the orchestration of FoxP3 leading to competitive fitness of Treg cells in leprosy.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica/genética , Subunidade alfa de Receptor de Interleucina-2/genética , Hanseníase/genética , Transcrição Gênica/genética , Adolescente , Adulto , Linfócitos T CD4-Positivos/metabolismo , Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Antígeno CTLA-4/metabolismo , Proliferação de Células , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Feminino , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica/imunologia , Histona Desacetilases/genética , Histona Desacetilases/imunologia , Histona Desacetilases/metabolismo , Humanos , Interleucina-2/genética , Interleucina-2/imunologia , Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-2/imunologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Hanseníase/imunologia , Hanseníase/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/imunologia , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Mycobacterium leprae/genética , Mycobacterium leprae/imunologia , Mycobacterium leprae/metabolismo , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Transcrição Gênica/imunologia , Adulto Jovem
11.
Crit Rev Anal Chem ; : 1-41, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593050

RESUMO

In recent years, the field of Supramolecular Chemistry has witnessed tremendous progress owing to the development of versatile optical sensors for the detection of harmful biological analytes. Nitrobenzoxadiazole (NBD) is one such scaffold that has been exploited as fluorescent probes for selective recognition of harmful analytes and their optical imaging in various cell lines including HeLa, PC3, A549, SMMC-7721, MDA-MB-231, HepG2, MFC-7, etc. The NBD-derived molecular probes are majorly synthesized from the chloro derivative of NBD via nucleophilic aromatic substitution. This general NBD moiety ligation method to nucleophiles has been leveraged to develop various derivatives for sensing analytes. NBD-derived probes are extensively used as optical sensors because of remarkable properties like excellent stability, large Stoke's shift, high efficiency and stability, visible excitation, easy use, low cost, and high quantum yield. This article reviewed NBD-based probes for the years 2017-2023 according to the sensing of analyte(s), including cations, anions, thiols, and small molecules like hydrogen sulfide. The sensing mechanism, designing of the probe, plausible binding mechanism, and biological application of chemosensors are summarized. The real-time application of optical sensors has been discussed by various methods, such as paper strips, molecular logic gates, smartphone detection, development of test kits, etc. This article will update the researchers with the in vivo and in vitro biological applicability of NBD-based molecular probes and challenges the research fraternity to design, propose, and develop better chemosensors in the future possessing commercial utility.

12.
Org Biomol Chem ; 10(40): 8076-81, 2012 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-22932925

RESUMO

A new naphthalimide-rhodamine-based dyad in CH(3)CN-HEPES (1 : 1) buffer solution exhibits fluorescence resonance energy transfer (FRET) from naphthalimide to the rhodamine moiety on addition of only Hg(2+) ions and allows ratiometric absorption and fluorimetric estimation of Hg(2+) ions between 50 nM (10 ppb) to 2 µM (0.4 ppm). FRET-induced fluorescence changes were recovered again by the subsequent addition of thiol amino acids via reverse FRET. The interconversion of probe and via the complexation/decomplexation by the modulation of Hg(2+)/Cys exhibited a selective probe for biothiols in real samples.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Mercúrio/análise , Naftalimidas/química , Compostos Organometálicos/química , Rodaminas/química , Compostos de Sulfidrila/análise , Corantes Fluorescentes/síntese química , Estrutura Molecular , Compostos Organometálicos/síntese química
13.
Heliyon ; 8(12): e12122, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36568679

RESUMO

A solitary wave is the dispersion-less solution of nonlinear evolutionary equations that travels at a constant speed without dissipating its energy. The purpose of this article is to provide insight into the discovery and history of solitons. The different types of the solitons are discussed in brief that is helpful for the researchers. For the discussion of the nature of solitons, the solution behavior of the Korteweg de Vries equation (KdV), the sine-Gordon (SG), the Camassa-Holm (CH) equation, and the nonlinear Schrodinger (NLS) equation are considered. This article deals with the various applications of solitons in different fields such as biophysics, nonlinear optics, Bose-Einstein condensation, plasma physics, Josephson junction, etc. focusing on the properties of solitons based on their classification.

14.
Eur J Med Chem ; 166: 267-280, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30721822

RESUMO

A series of phenanthro[9,10-d]imidazole/oxazole and acenaphtho[1,2-d]imidazole with different aryl groups at C2-position has been synthesized. These compounds were in vitro evaluated for antitumor activity against a panel of 60 human cancer cell lines. Compound 8 exhibits higher cytotoxicity towards leukemia, colon, melanoma, renal, and breast cancer cell lines than the other evaluated cell panels and low toxicity against normal cell line Hek293. The binding properties of compound 8 with DNA have been investigated with absorption, emission and circular dichroism as well as thermal denaturation experiments which indicate intercalation with base pairs of human and calf thymus DNA. The molecular docking and site-selective binding studies also reveal the predominant intercalation of compound 8 in base pairs of DNA. The interaction between thiazolidine based phenanthrene 8 and serum albumins (HSA and BSA), transport proteins, has also been explored which shows quenching of fluorescence through static mechanism. The thermodynamic parameters, obtained from van't Hoff relationship indicate the prevalence of hydrogen-bonding/hydrophobic interactions for the binding phenomenon.


Assuntos
DNA/metabolismo , Albumina Sérica/metabolismo , Tiazolidinedionas/síntese química , Tiazolidinedionas/farmacologia , Animais , Bovinos , Técnicas de Química Sintética , DNA/química , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico , Tiazolidinedionas/química , Tiazolidinedionas/metabolismo
15.
J Biotechnol ; 269: 16-34, 2018 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-29408199

RESUMO

In recent years, substantial credibility in employing Solid-State Fermentation (SSF) technique has been witnessed owing to its numerous advantages over submerged fermentation (SmF). In spite of enormous advantages, true potential of SSF technology has not been fully realized at industrial scale. The lack of rational and scalable bioreactor designs backed by mathematical models and automated control system that could successfully address heterogeneity with respect to heat and mass, and also operate aseptically, remains the prime reason for it. As a result, there still exists vast scope in SSF bioreactor research and development to facilitate broad spectrum of biotechnological applications. The present article reviews state-of-the-art in SSF technology with focus on bioreactors that have been employed for bioprocess applications, in particular, enzyme production. Based on the mode of operation, bioreactors are divided into four categories with emphasis on design features, effect of operating conditions on productivity, applications and limitations. Selected modeling studies developed over the years, have been revised and presented in problem specific manner in order to address the limitations. Some interesting designs including few recent ones that have been proposed and/or employed at pilot and industrial levels are discussed in more detail.


Assuntos
Reatores Biológicos , Microbiologia Industrial , Desenho de Equipamento , Fermentação
16.
PLoS One ; 11(1): e0147864, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26808690

RESUMO

Why only a subpopulation (about 15%) of humans develops liver cirrhosis due to alcohol is a critical as yet unanswered question. Liver-specific depletion of augmenter of liver regeneration (ALR) protein in mice causes robust steatosis and hepatocyte apoptosis by 2 weeks; these pathologies regress subsequently with return of ALR expression even at lower than control levels, but the mice develop modest steatohepatitis by 8 weeks. We aimed to investigate whether chronic alcohol ingestion promotes excessive hepatic fibrosis in these ALR-deficient mice. Liver-specific ALR-deficient and wild type (WT) female mice (8-10 weeks old) were placed on 4% alcohol-supplemented or isocaloric diet for 4 weeks. Liver sections were examined for histopathology, and parameters of steatosis and fibrosis were quantified. The mRNA expression of alcohol dehydrogenase-1, acetaldehyde dehydrogenase-1 and cytochrome P450-2E1 increased in WT mice but decreased in ALR-deficient mice upon alcohol ingestion. While alcohol induced steatosis and mild inflammation in WT mice, ALR-deficient mice showed minimal steatosis, strong hepatocellular injury and inflammation, prominent ductular proliferation, and robust fibrosis. Compared to the WT mice, alcohol feeding of ALR-deficient mice resulted in significantly greater increase in hepatic TNFα and TGFß, and oxidative stress; there was also hepatic iron accumulation, robust lipid peroxidation and mitochondrial DNA damage. Importantly, similar to ALR-deficient mice, lower hepatic ALR levels in human alcoholic liver cirrhosis were associated with increased iron content, reduced expression of alcohol dehydrogenase and acetaldehyde dehydrogenase, and elevated fibrogenic markers. We conclude that ALR deficiency or anomaly can play a critical role in alcohol-induced hepatic fibrosis/cirrhosis, mechanisms of which may involve dysregulation of alcohol metabolism and iron homeostasis, mitochondrial damage and oxidative injury.


Assuntos
Etanol/toxicidade , Cirrose Hepática/patologia , Regeneração Hepática/fisiologia , Álcool Desidrogenase/metabolismo , Família Aldeído Desidrogenase 1 , Animais , Feminino , Isoenzimas/metabolismo , Peroxidação de Lipídeos , Hepatopatias/etiologia , Hepatopatias/metabolismo , Camundongos , Retinal Desidrogenase/metabolismo
17.
Mol Immunol ; 56(4): 513-20, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23911408

RESUMO

Leprosy is a chronic human disease that results from infection of Mycobacterium leprae. T reg cells have been shown to have important implications in various diseases. However, in leprosy, it is still unclear whether T regs can mediate immune suppression during progression of the disease. In the present study, we have proposed the putative mechanism leading to high proportion of T reg cells and investigated its significance in human leprosy. High levels of TGF-ß followed by adaptation of FoxP3(+) naive and memory (CD4(+)CD45RA(+)/RO(+)) T cells were observed as the principal underlying factors leading to higher generation of T reg cells during disease progression. Furthermore, TGF-ß was found to be associated with increased phosphorylation-mediated-nuclear-import of SMAD3 and NFAT towards BL/LL pole to facilitate FoxP3 expression in these cells, the same as justified after using nuclear inhibitors of SMAD3 (SIS3) and NFAT (cyclosporin A) in CD4(+)CD25(+) cells in the presence of TGF-ß and IL-2. Interestingly, low ubiquitination of FoxP3 in T reg cells of BL/LL patients was revealed to be a major driving force in conferring stability to FoxP3 which in turn is linked to suppressive potential of T regs. The present study has also pinpointed the presence of CD4(+)CD25(+)IL-10(+) sub class of T regs (Tr1) in leprosy.


Assuntos
Fatores de Transcrição Forkhead/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Hanseníase/imunologia , Linfócitos T Reguladores/imunologia , Acetilação , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Adolescente , Adulto , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Ciclosporina/farmacologia , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Imunossupressores/farmacologia , Interleucina-2/imunologia , Interleucina-2/metabolismo , Interleucina-2/farmacologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Isoquinolinas/farmacologia , Hanseníase/metabolismo , Hanseníase/patologia , Antígenos Comuns de Leucócito/imunologia , Antígenos Comuns de Leucócito/metabolismo , Masculino , Pessoa de Meia-Idade , Fatores de Transcrição NFATC/antagonistas & inibidores , Fatores de Transcrição NFATC/imunologia , Fatores de Transcrição NFATC/metabolismo , Fosforilação/efeitos dos fármacos , Piridinas/farmacologia , Pirróis/farmacologia , Proteína Smad3/antagonistas & inibidores , Proteína Smad3/imunologia , Proteína Smad3/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Ubiquitinação , Adulto Jovem
18.
Immunobiology ; 218(12): 1488-96, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23816300

RESUMO

The defective antigen presenting ability of antigen presenting cells (APCs) modulates host cytokines and co-stimulatory signals that may lead to severity of leprosy. In the present study, we sought to evaluate the phenotypic features of APCs along with whether DC SIGN (DC-specific intercellular adhesion molecule-grabbing nonintegrin) influences IL-10 production while moving from tuberculoid (BT/TT) to lepromatous (BL/LL) pole in leprosy pathogenesis. The study revealed an increased expression of DC SIGN on CD11c⁺ cells from BL/LL patients and an impaired form of CD83 (∼50 kDa). However, the cells after treatment with GM-CSF+IL-4+ManLAM showed an increased expression of similar form of CD83 on DCs. Upon treatment with ManLAM, DCs were found to show increased nuclear presence of NF-κB, thus leading to higher IL-10 production. High IL-10 production from ManLAM treated PBMCs further suggested the role of DC SIGN in subverting the DCs function towards BL/LL pole of leprosy. Anti-DC SIGN treatment resulting in restricted nuclear ingression of NF-κB as well as its acetylation along with enhanced T cell proliferation validated our findings. In conclusion, Mycobacterium leprae component triggers DC SIGN on DCs to induce production of IL-10 by modulating intracellular signalling pathway at the level of transcription factor NF-κB towards BL/LL pole of disease.


Assuntos
Moléculas de Adesão Celular/metabolismo , Células Dendríticas/imunologia , Lectinas Tipo C/metabolismo , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Receptores de Superfície Celular/metabolismo , Linfócitos T/imunologia , Acetilação/efeitos dos fármacos , Adolescente , Adulto , Anticorpos Bloqueadores/farmacologia , Antígenos CD/metabolismo , Moléculas de Adesão Celular/genética , Proliferação de Células , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/microbiologia , Progressão da Doença , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Evasão da Resposta Imune , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-4/farmacologia , Lectinas Tipo C/genética , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Receptores de Superfície Celular/genética , Adulto Jovem
19.
Bioresour Technol ; 102(22): 10641-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21945206

RESUMO

Present study introduces linseed oil cake as a novel substrate for phytase production by Rhizopus oryzae. Statistical approach was employed to optimize various medium components under solid state fermentation (SSF). An overall 8.41-fold increase in phytase production was achieved at the optimum concentrations (w/w, mannitol, 2.05%; ammonium sulfate, 2.84% and phosphate, 0.38%). Further enhancement by 59% was observed due to a novel strain improvement approach. Purified phytase (∼34 kDa) showed optimal temperature of 45 °C, dual pH optima at 1.5 and 5.5 and possesses high catalytic efficiency (2.38×10(6) M(-1) s(-1)). Characterization study demonstrates the phytase as highly thermostable and resistant to proteolysis, heavy metal ions, etc. Furthermore, an improved HPLC method was introduced to confirm the ability of phytase to degrade phytic acid completely and was found to be an efficient method.


Assuntos
6-Fitase/biossíntese , 6-Fitase/isolamento & purificação , Biotecnologia/métodos , Fermentação , Rhizopus/enzimologia , Agricultura , Análise de Variância , Cromatografia Líquida de Alta Pressão , Hidrólise , Modelos Biológicos , Mutação/genética , Ácido Fítico/metabolismo , Análise de Regressão , Reprodutibilidade dos Testes , Especificidade por Substrato , Fatores de Tempo
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