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1.
Nat Commun ; 13(1): 7561, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36476471

RESUMO

Global overturning circulation underwent significant changes in the late Miocene, driven by tectonic forcing, and impacted the global climate. Prevailing hypotheses related to the late Miocene deep water circulation (DWC) changes driven by the closure of the Central American Seaways (CAS) and its widespread impact remains untested due to the paucity of suitable records away from the CAS region. Here, we test the hypothesis of the large-scale circulation changes by providing a high-resolution record of DWC since the late Miocene (11.3 to ~2 Ma) from the north-western Indian Ocean. Our investigation reveals a progressive shift from Pacific-dominated DWC before ~9.0 Ma to the onset of a modern-like DWC system in the Indian Ocean comprising of Antarctic bottom water and northern component water during the Miocene-Pliocene transition (~6 Ma) caused by progressive shoaling of the CAS and suggests its widespread impact.


Assuntos
População da América Central , Água , Humanos , Oceano Índico , Regiões Antárticas
2.
Sci Total Environ ; 843: 157035, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35780895

RESUMO

El Niño Southern Oscillation (ENSO) is one of the dominant climate modes influencing global precipitation and temperature. ENSO has a large impact on the monsoonal precipitations over the Indian subcontinent and thereby influences hydrological conditions. Due to dearth of long-term instrumental records of the hydrological parameters on sufficient spatial resolution, it is difficult to assess the impact of ENSO on regional hydrology. Though several geochemical proxies have been used to reconstruct past ENSO events through tracing the changes in past hydrological and climatic parameters, however, such reconstructions are often complicated by the influence of multiple processes and/or factors and their nonlinear relation with the proxy records. In this study, Sr isotope composition (87Sr/86Sr) was measured in Porites coral from the Lakshadweep, south-eastern Arabian Sea to reconstruct past ENSO events and to trace its regional hydrological impacts. The high precision measurements of 87Sr/86Sr in Lakshadweep coral show resolvable variations ranging from 0.709080 to 0.709210. The 87Sr/86Sr record shows an inverse relation with Niño 3.4 record; lower values matched with El Niño years and higher values with La Niña years. Our investigation reveals that ENSO driven precipitation changes impacted submarine groundwater discharge (SGD) to the Minicoy Atoll and resulted in 87Sr/86Sr variations of the Minicoy Atoll water. Therefore, deviation from the average seawater 87Sr/86Sr value can be quantified in terms of SGD contribution to the Minicoy Atoll. Our estimates based on binary mixing between seawater and SGD 87Sr/86Sr suggest a significant supply of SGD, maximum up to ~20 % of the total volume of the Minicoy Atoll during La Niña years due to higher rainfall compared to El Niño years. This finding highlights potential application of coral 87Sr/86Sr record as an alternate proxy to reconstruct past ENSO events and to trace its quantitative impact on regional hydrology, chemical and nutrient fluxes to coastal oceans via SGD.


Assuntos
Antozoários , El Niño Oscilação Sul , Isótopos de Estrôncio , Animais , Antozoários/química , Hidrologia , Oceanos e Mares , Isótopos de Estrôncio/análise , Temperatura
3.
Cytokine ; 152: 155821, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35151928

RESUMO

Leprosy type 1 reaction (T1R) is a cell-mediated inflammatory reaction which involves skin and peripheral nerves in leprosy. Lesions with T1R have higher production of IL-17 cytokine from CD4+ T cells along with lower TGF-ß producing FOXP3+ CD4+ Tregs. IL-21 is an important cytokine that promotes the development and stability of Th17 cells in an autocrine manner. It can play an important role in the pathogenesis of T1R in leprosy. However, the mechanism by which IL-21 influences the pathogenic progress of leprosy T1R remains poorly understood. In the present study, we evaluated the expression of IL-21 cytokine in skin lesions of both non-reactional (NR) and T1R via immuno-histochemistry and quantitative PCR (qPCR). Further, expression of various genes (IL-17A, IL-17F, TGF-ß, FOXP3, RORC and IL-21) was also measured by qPCR in cultured cells. We also analyzed the secretion of various cytokines such as of IL-21, IL-17A/F and TGF-ß in the culture supernatants by ELISA. In addition, differentiation of Th17 and Treg cells were studied in PBMC cultures after stimulation with Mycobacterium leprae sonicated antigens and rIL-21 for 48 hrs and the phenotypes of Th17 and Tregs were determined by flowcytometric analysis. Our results clearly indicate that IL-21+T cells were significantly higher in both peripheral blood and skin lesions of T1R as compared to NR patients. Moreover, we observed that recombinant IL-21 cytokine inhibited TGF-ß producing Treg cells differentiation along with up-regulating Th17 cells under in-vitro conditions. The gene expression of IL-21 was significantly negatively correlated with Treg and positively correlated with Th17 cell markers in T1R patients. Our results suggested that IL-21 promotes T1R mediated inflammation via modulating the balance of Th17 and Treg cell populations.


Assuntos
Hipersensibilidade , Hanseníase , Citocinas , Fatores de Transcrição Forkhead , Humanos , Inflamação , Interleucina-17/metabolismo , Interleucinas , Leucócitos Mononucleares/metabolismo , Linfócitos T Reguladores , Células Th17 , Fator de Crescimento Transformador beta/metabolismo
4.
Oxid Med Cell Longev ; 2021: 4572471, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33747345

RESUMO

The brain is a sexually dimorphic organ that implies different functions and structures depending on sex. Current pharmacological approaches against different neurological diseases act distinctly in male and female brains. In all neurodegenerative diseases, including Alzheimer's disease (AD), sex-related outcomes regarding pathogenesis, prevalence, and response to treatments indicate that sex differences are important for precise diagnosis and therapeutic strategy. Pathogenesis of AD includes vascular dementia, and in most cases, this is accompanied by metabolic complications with similar features as those assembled in diabetes. This review discusses how AD-associated dementia and diabetes affect cognition in relation to sex difference, as both diseases share similar pathological mechanisms. We highlight potential protective strategies to mitigate amyloid-beta (Aß) pathogenesis, emphasizing how these drugs act in the male and female brains.


Assuntos
Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/terapia , Cognição , Diabetes Mellitus/fisiopatologia , Diabetes Mellitus/terapia , Caracteres Sexuais , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Diabetes Mellitus/genética , Diabetes Mellitus/patologia , Feminino , Humanos , Masculino , Estresse Oxidativo , Fatores de Risco
5.
Sci Rep ; 10(1): 15143, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934336

RESUMO

Th17 cells play vital role during pathogenesis of leprosy reactions. Previously, we have reported that IL-23 is involved in Th17 cells differentiation. Subsequently, our group also showed that IL-6 induces Th17 cell differentiation along with TGF-ß in leprosy reactions. Here, we next asked the question that whether IL-6 or IL-23 induced Th17 cells are different in nature? In this study, Type 1 Reactions (T1R) showed significantly (p < 0.001) higher percentage of IL-17A producing CD4+IL6R+ T cells as compared to non-reaction (NR) patients. Furthermore, recombinant IL-6, IL-23 and TGF-ß promoted IL-17A secretion by CD4+IL6R+ T cells. Subsequently, IL-6R and IL-23R blocking experiments showed significantly (p < 0.002) down regulated IL-17A in T1R reaction as compared to NR leprosy patients. The present study for the first time establishes that pathogenic Th17 cells produce IL-17 in an IL-6 dependent manner in leprosy T1R reactions. Thus, present approaches that specifically target Th17 cells and/or the cytokines that promote their development, such as IL-6, TGF-ß and IL-23A may provide more focused treatment strategies for the management of Mycobacterium leprae and its reactions.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Interleucina-6/metabolismo , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Receptores de Interleucina-6/metabolismo , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Adolescente , Adulto , Feminino , Humanos , Interleucina-17/imunologia , Interleucina-17/metabolismo , Hanseníase/metabolismo , Hanseníase/microbiologia , Hanseníase/patologia , Masculino , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Adulto Jovem
6.
J Perinat Med ; 47(7): 724-731, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31318696

RESUMO

Background Pregnancy is associated with biochemical changes leading to increased nutritional demands for the developing fetus that result in altered micronutrient status. The Indian dietary pattern is highly diversified and the data about dietary intake patterns, blood micronutrient profiles and their relation to low birthweight (LBW) is scarce. Methods Healthy pregnant women (HPW) were enrolled and followed-up to their assess dietary intake of nutrients, micronutrient profiles and birthweight using a dietary recall method, serum analysis and infant weight measurements, respectively. Results At enrolment, more than 90% of HPW had a dietary intake below the recommended dietary allowance (RDA). A significant change in the dietary intake pattern of energy, protein, fat, vitamin A and vitamin C (P < 0.001) was seen except for iron (Fe) [chi-squared (χ2) = 3.16, P = 0.177]. Zinc (Zn) deficiency, magnesium deficiency (MgDef) and anemia ranged between 54-67%, 18-43% and 33-93% which was aggravated at each follow-up visit (P ≤ 0.05). MgDef was significantly associated with LBW [odds ratio (OR): 4.21; P = 0.01] and the risk exacerbate with the persistence of deficiency along with gestation (OR: 7.34; P = 0.04). Pre-delivery (OR: 0.57; P = 0.04) and postpartum (OR: 0.37; P = 0.05) anemia, and a vitamin A-deficient diet (OR: 3.78; P = 0.04) were significantly associated with LBW. LBW risk was much higher in women consuming a vitamin A-deficient diet throughout gestation compared to vitamin A-sufficient dietary intake (OR: 10.00; P = 0.05). Conclusion The studied population had a dietary intake well below the RDA. MgDef, anemia and a vitamin A-deficient diet were found to be associated with an increased likelihood of LBW. Nutrient enrichment strategies should be used to combat prevalent micronutrient deficiencies and LBW.


Assuntos
Deficiências Nutricionais , Dieta/métodos , Recém-Nascido de Baixo Peso/metabolismo , Micronutrientes , Complicações na Gravidez , Adulto , Peso ao Nascer/fisiologia , Deficiências Nutricionais/sangue , Deficiências Nutricionais/diagnóstico , Deficiências Nutricionais/epidemiologia , Deficiências Nutricionais/etiologia , Comportamento Alimentar/fisiologia , Feminino , Humanos , Índia/epidemiologia , Micronutrientes/sangue , Micronutrientes/classificação , Micronutrientes/deficiência , Avaliação das Necessidades , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/etiologia , Serviços Preventivos de Saúde , Recomendações Nutricionais , Fatores de Risco
7.
J Cell Biochem ; 120(9): 15119-15130, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31021496

RESUMO

Calcium/calmodulin-dependent protein kinase IV (CAMKIV) is a key regulatory molecule of cell signaling, and thereby controls its growth and proliferation, including expression of certain genes. The overexpression of CAMKIV is directly associated with the development of different types of cancers. Hesperidin is abundantly found in citrus fruits and exhibits wide range of pharmacological activities including anti-inflammatory, antibacterial and anticancerous effects. We have investigated binding mechanism of hesperidin with the CAMKIV using molecular docking methods followed by fluorescence quenching and isothermal titration calorimetric assays. An appreciable binding affinity of hesperidin was observed with CAMKIV during fluorescence quenching and isothermal titration calorimetric studies. Efficacy of hesperidin to inhibit the growth of human hepatic carcinoma (HepG2) and neuroblastoma (SH-SY5Y) cancer cell lines were investigated. Hesperidin has significantly reduced the proliferation of HepG2 and SH-SY5Y cells and induces apoptosis by activating the caspase-3-dependent intrinsic pathway through the upregulation of proapoptotic Bax protein. Hesperidin treatment reduces the mitochondrial membrane potential of HepG2 and SH-SY5Y cells. All these observations clearly anticipated hesperidin a potent inhibitor of CAMKIV which may be further exploited a newer therapeutic approach for the management of different cancer types.


Assuntos
Apoptose , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/metabolismo , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Hesperidina/farmacologia , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Neuroblastoma/enzimologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Células HEK293 , Hesperidina/química , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Neuroblastoma/patologia , Transdução de Sinais/efeitos dos fármacos
8.
J Inflamm Res ; 11: 377-388, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30319283

RESUMO

BACKGROUND: The clinical forms of cutaneous tuberculosis (CTB) consist of a spectrum that reflects the host's immune response to Mycobacterium tuberculosis; it provides an ideal model to study the immunological dysregulation in humans. IL-17 plays an important role in initial immune response and is involved in both immune-mediated protection and pathology during M. tuberculosis infection. TGF-ß producing regulatory T-cells (Tregs) are high in leprosy patients and responsible for immune suppression. However, in CTB, the involvement of Tregs and Th17 remains unevaluated. OBJECTIVE: To study the role of proinflammatory Th17 and Treg cells in the human CTB. METHODS: Blood and skin biopsies of CTB patients and healthy controls (HC) were included in the study. Flow cytometric analysis of IL-17, FOXP3, and TGF-ß in blood was done followed by immunohistochemistry on paraffin-embedded skin sections. Expression of IFN-γ, TGF-ß, and IL-17 was evaluated by quantitative real-time PCR. RESULTS: We found significant (P<0.0002) lower expression of proinflammatory IL-17 and IFN-γ (P<0.01) in CTB skins as compared to HC. However, the frequency of TGF-ß producing Treg cells was found to be high in CTB patients (P<0.001) as compared to HC. A similar type of profile was observed by flow cytometric analysis. Treg cells produced suppressive cytokine TGF-ß which showed a positive correlation with FOXP3 gene expression. CONCLUSION: Our study found an increase in lineage-specific CD4+ Tregs in CTB as compared to the HC individuals. Such cells secrete TGF-ß, a suppressive cytokine and may play a role in negatively regulating the T-cell immune responses in CTB. In addition, Tregs with TGF-ß may downregulate Th17 cell responses leading to the antigen-specific anergy associated with CTB patients.

9.
Front Immunol ; 9: 1636, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30083152

RESUMO

Regulatory B cells (Bregs) are known to exhibit their regulatory functions through interleukin-10 (IL-10) cytokine which suppress inflammation. There are only a few studies explaining the phenotype and functioning of these cells in contribution to host immunity in leprosy. Here, we evaluated the role of IL-10 producing Bregs in the pathogenesis of leprosy and assessed their immunoregulatory effects on Tregs and effector T cells. We found an increased frequency of Bregs and increased expression of their immune modulatory molecules (IL-10, FoxP3, and PDL-1) in leprosy patients. The potential immunoregulatory mechanism of Bregs was also investigated using MACS sorted Teff (CD4+CD25-) and Treg (CD4+CD25+) cells were cocultured with Bregs to elucidate the effects of Bregs on effector T and regulatory T cells. Cell coculture results showed that purified Bregs cells from leprosy patients convert CD4+CD25- cells into CD4+CD25+ cells. Cell coculture experiments also demonstrated that leprosy derived IL-10 producing Bregs enhance FoxP3 and PD-1 expression in Tregs and enhanced Tregs activity. Blocking of IL-10 receptor confirmed that IL-10 producing Breg has immunomodulatory effect on Tregs and effector T cells as effector T cells are not converted into Tregs and enhanced expression of FoxP3 and PD-1 was not observed on Tregs. Collectively, these findings demonstrate that IL-10 producing Breg cells play an important mechanism in controlling the immunopathogenesis of leprosy and have an immunomodulatory effect on Tregs and effector T cells. Our findings may pave way for novel targets of IL-10 producing Bregs for immunotherapy in leprosy patients.

10.
Immunol Lett ; 200: 55-65, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30006101

RESUMO

BACKGROUND: Leprosy reactions appear episodically in leprosy patients, which lead to high inflammation, morbidity and peripheral nerve damage. The role of Th17 cell has been well studied in leprosy reactions but the role of γδ or unconventional T cells which is an other major source of IL-17 in many diseases, not studied in leprosy reactional episodes. OBJECTIVE: The aim of the present study to elucidate the role of γδ T cells in leprosy reactions. METHODOLOGY: A total of 40 untreated non-reaction and reactions patients were recruited. PBMCs were isolated and stimulated with M. leprae sonicated antigen (MLSA) for 48 h and immuno-phenotyping was done using flow cytometry. Moreover, γδ T cells were isolated by Magnetic beads technology and mRNA expression of IL-17, IFN-γ, TGF-ß and FOXP3 were analyzed by real-time PCR (qPCR) and cytokine was estimated in the culture supernatant by ELISA. RESULTS: γδ T cells were significantly increased in both Reversal reaction (RR) and Erythema nodosum leprosum (ENL) reaction patients. These cells produced significant amount of IL-17 and IFN-γ. Furthermore, CD3+TCRγδ+ T cells expressed transient FOXP3 with a low amount of TGF-ß in both reactions as compared to stable patients. Moreover, low TGF-ß producing TCR-γδ cells were associated with low phosphorylation of STAT5A. CONCLUSION: This study will add to our understanding of the immunological features that mediate and regulate the pathogenesis of leprosy and may helpful to reduce the immuno-pathogenesis of leprosy reaction by targeting these cells.


Assuntos
Inflamação/etiologia , Inflamação/metabolismo , Hanseníase/etiologia , Hanseníase/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Antígenos de Superfície/metabolismo , Biomarcadores , Citocinas/metabolismo , Expressão Gênica , Humanos , Imunofenotipagem , Inflamação/patologia , Hanseníase/patologia , Fosforilação , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
11.
Infect Genet Evol ; 60: 160-172, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29501636

RESUMO

Hepatitis C virus plays a significant role in the development of hepatocellular carcinoma (HCC) globally. The pathogenic mechanisms of hepatocellular carcinoma with HCV infection are generally linked with inflammation, cytokines, fibrosis, cellular signaling pathways, and liver cell proliferation modulating pathways. HCV encoded proteins (Core, NS3, NS4, NS5A) interact with a broad range of hepatocytes derived factors to modulate an array of activities such as cell signaling, DNA repair, transcription and translational regulation, cell propagation, apoptosis, membrane topology. These four viral proteins are also implicated to show a strong conversion potential in tissue culture. Furthermore, Core and NS5A also trigger the accretion of the ß-catenin pathway as a common target to contribute viral induced transformation. There is a strong association between HCV variants within Core, NS4, and NS5A and host single nucleotide polymorphisms (SNPs) with the HCC pathogenesis. Identification of such viral mutants and host SNPs is very critical to determine the risk of HCC and response to antiviral therapy. In this review, we highlight the association of key variants, mutated proteins, and host SNPs in development of HCV induced HCC. How such viral mutants may modulate the interaction with cellular host machinery is also discussed.


Assuntos
Carcinoma Hepatocelular , Hepacivirus/genética , Hepatite C , Neoplasias Hepáticas , Polimorfismo de Nucleotídeo Único/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Genoma Viral/genética , Hepatite C/complicações , Hepatite C/genética , Hepatite C/virologia , Interações Hospedeiro-Patógeno/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Mutação/genética , Mapas de Interação de Proteínas , Proteínas Virais/genética
12.
Curr Protein Pept Sci ; 19(9): 889-899, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28847289

RESUMO

Leprosy is an infectious disease caused by non-cultivable bacteria Mycobacterium leprae. Ridley and Jopling classified the disease into five polar forms, Tuberculoid (TT) and Lepromatous (LL), in between two forms of the disease Borderline tuberculoid (BT), Borderline (BB) and Borderline lepromatous (BL) are laid. The tuberculoid type (BT/TT) leprosy patients show good recall of cellmediated immune (CMI) response and Th1 type of immune response, while lepromatous leprosy (LL) patients show defect in cell-mediated immunity to the causative agent and Th2 type of immune response. Due to distinct clinical and immunological spectra of the disease, leprosy attracted immunologists to consider an ideal model for the study of deregulations of various immune reactions. Recent studies show that Tregs, Th3 (TGF-ß, IL-10), IL-35 producing Treg immune response associated with the immune suppressive environment, survival of bugs. IL-17 producing Th17 immune response associated with tuberculoid leprosy and play protective role. γδ T cells also increased from tuberculoid to lepromatous pole of leprosy. In this review, we will discuss the role of various subtypes of T-cell and their cytokines in the pathogenesis of leprosy.


Assuntos
Hanseníase/imunologia , Linfócitos T/fisiologia , Anticorpos/química , Anticorpos/metabolismo , Biomarcadores/metabolismo , Citocinas/metabolismo , Progressão da Doença , Descoberta de Drogas , Humanos , Imunoterapia/métodos , Hanseníase/classificação , Hanseníase/terapia , Mycobacterium leprae , Linfócitos T/patologia , Linfócitos T Reguladores/fisiologia , Células Th1/fisiologia , Células Th2/fisiologia
13.
Mol Cell Biochem ; 438(1-2): 35-45, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28744811

RESUMO

Human calcium/calmodulin-dependent protein kinase IV (CAMKIV) is a member of Ser/Thr kinase family, and is associated with different types of cancer and neurodegenerative diseases. Vanillin is a natural compound, a primary component of the extract of the vanilla bean which possesses varieties of pharmacological features including anti-oxidant, anti-inflammatory, anti-bacterial and anti-tumor. Here, we have investigated the binding mechanism and affinity of vanillin to the CAMKIV which is being considered as a potential drug target for cancer and neurodegenerative diseases. We found that vanillin binds strongly to the active site cavity of CAMKIV and stabilized by a large number of non-covalent interactions. We explored the utility of vanillin as anti-cancer agent and found that it inhibits the proliferation of human hepatocyte carcinoma (HepG2) and neuroblastoma (SH-SY5Y) cells in a dose-dependent manner. Furthermore, vanillin treatment resulted into the significant reduction in the mitochondrial membrane depolarization and ROS production that eventually leads to apoptosis in HepG2 and SH-SY5Y cancer cells. These findings may offer a novel therapeutic approach by targeting the CAMKIV using natural product and its derivative with a minimal side effect.


Assuntos
Antineoplásicos , Benzaldeídos , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina , Carcinoma Hepatocelular , Neoplasias Hepáticas , Simulação de Acoplamento Molecular , Proteínas de Neoplasias , Neuroblastoma , Antineoplásicos/química , Antineoplásicos/farmacologia , Benzaldeídos/química , Benzaldeídos/farmacologia , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/química , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Neuroblastoma/tratamento farmacológico , Neuroblastoma/enzimologia , Neuroblastoma/genética , Neuroblastoma/patologia , Ligação Proteica
14.
Immunol Lett ; 184: 61-66, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28235552

RESUMO

Leprosy is an ancient disease caused by gram positive, rod shaped bacilli called Mycobacterium leprae. Patients present with varied clinico-pathological disease depending on the host immune response to Mycobacterium leprae. Thus tuberculoid (TT) and lepromatous (LL) patients represent two ends of a spectrum where the former shows limited disease, high T cell mediate immune (CMI) response and low antibody (HI) levels in serum. In contrast the latter has low T cell and high humoral immune response i.e antibody levels. The mechanisms underlying these differences have been investigated intensely; however, there is no consensus on the primary immunological basis. Over three decades, Th1 and Th2 paradigm were thought to underling tuberculoid and lepromatous disease respectively. However many patients were shown to have mixed Th1/Th2 pattern of (IFN-γ/IL-4) cytokines. The present review was undertaken with a view to understand the T cells and cytokine dysregulation in leprosy. In recent years the sub classes of T cells that are Regulatory in nature (Treg) have been implicated in immune diseases where they were shown to suppress T cell functions. Additionally Th17 cells secreting IL-17A, IL17F, were implicated in immune inflammation. Taken together these regulatory cells may play a part in influencing immune responses in leprosy.


Assuntos
Hanseníase/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Anergia Clonal/imunologia , Citocinas/metabolismo , Progressão da Doença , Suscetibilidade a Doenças , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Celular , Hanseníase/metabolismo , Hanseníase/microbiologia , Hanseníase/patologia , Mycobacterium leprae/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo
15.
Exp Dermatol ; 26(10): 946-948, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28109171

RESUMO

This study, for the first time, reveals the role of M. leprae-specific CD4+ TCRγδ+ FoxP3+ cells in the progression and pathogenesis of leprosy. Co-culture with CD4+ CD25- cells suggested the immunosuppressive nature of CD4+ TCRγδ+ cells in dose-dependent manner. Isolation of CD4+ TCRγδ+ cells from leprosy patients and then culture in presence of M. leprae cell wall antigens (MLCwA) along with TGF ß, IPP and IL-2 suggested that these cells are M. leprae specific. TGF-ß-mediated SMAD3 signalling was turned out to be major factor towards the expression of FoxP3 in these cells. SMAD3 silencing during induction of these cells barely showed the induction of FoxP3. High density of SMAD3 binding at TGFßRII in CD4+ TCRγδ+ FoxP3+ furthermore suggested the TGF-ß-directed SMAD3 signalling in these cells. Taken together the above data, we can conclude that CD4+ TCRγδ+ FoxP3+ cells possess the potential to track the severity of the disease in leprosy patients.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Tolerância Imunológica , Hanseníase Multibacilar/imunologia , Hanseníase Paucibacilar/imunologia , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Progressão da Doença , Fatores de Transcrição Forkhead/metabolismo , Humanos , Interferon gama/sangue , Interleucina-17/sangue , Hanseníase Multibacilar/sangue , Hanseníase Paucibacilar/sangue , Mycobacterium leprae/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Índice de Gravidade de Doença , Transdução de Sinais
16.
Mol Immunol ; 83: 72-81, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28110210

RESUMO

Leprosy is a bacterial disease caused by M. leprae. Its clinical spectrum reflects the host's immune response to the M. leprae and provide an ideal model to investigate the host pathogen interaction and immunological dysregulation. Tregs are high in leprosy patients and responsible for immune suppression of the host by producing IL-10 and TGF-ß cytokines. In leprosy, plasticity of Tregs remain unstudied. This is the first study describing the conversion of Tregs into Th1-like and Th17-like cells using in vitro cytokine therapy in leprosy patients. Peripheral blood mononuclear cells from leprosy patients were isolated and stimulated with M. leprae antigen (MLCwA), rIL-12 and rIL-23 for 48h. Expression of FoxP3 in CD4+CD25+ Tregs, intracellular cytokines IFN-γ, TGF-ß, IL-10 and IL-17 in Tregs cells were evaluated by flow cytometry (FACS) after stimulation. rIL-12 treatment increases the levels of pStat4 in Tregs and IFN-γ production. In the presence of rIL-23, pStat3+ and IL-17A+ cells increase. rIL-12 and r-IL-23 treatment downregulated the FoxP3 expression, IL-10 and TGF-ß production by Tregs and enhances the expression of co-stimulatory molecules (CD80, CD86). In conclusion rIL-12 converts Tregs into IFN-γ producing cells through STAT-4 signaling while rIL-23 converts Tregs into IL-17 producing cells through STAT-3 signaling in leprosy patients. This study may helpful to provide a new avenue to overcome the immunosuprression in leprosy patients using in vitro cytokine.


Assuntos
Diferenciação Celular/imunologia , Interleucina-12/imunologia , Interleucina-23/imunologia , Hanseníase/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Western Blotting , Regulação para Baixo , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Fatores de Transcrição Forkhead/imunologia , Humanos , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Cytokine ; 91: 82-88, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28038394

RESUMO

BACKGROUND: The clinical forms of leprosy consist of a spectrum that reflects the host's immune response to the M. leprae; it provides an ideal model to study the host pathogen interaction and immunological dysregulation in humans. IL-10 and TGF-ß producing Tregs are high in leprosy patients and responsible for immune suppression and M. leprae specific T cells anergy. In leprosy, involvement of IL-35 producing Tregs and Bregs remain unstudied. OBJECTIVE: To study the role of IL-35 producing Tregs and Bregs in the human leprosy. METHODS: Peripheral blood mononuclear cells from leprosy patients were isolated and stimulated with M. leprae antigen (MLCwA) for 48h. Intracellular cytokine IL-35 was evaluated in CD4+CD25+ Tregs, CD19+ cells by FACS. Expression of PD-1 on CD4+CD25+ Tregs, CD19+ cells and its ligand (PD-L1) on B cells, CD11c cells were evaluated by flow cytometry (FACS). Serum IL-35 level was estimated by ELISA. RESULTS: The frequency of IL-35 producing Tregs and Bregs cells were found to be high in leprosy patients (p<0.0001) as compared to healthy controls. These cells produced suppressive cytokine IL-35 which showed positive correlation with bacteriological index (BI) and TGF-ß producing Tregs, indicating its suppressive nature. We found higher expression of PD-1 on Tregs, B cell and its ligand (PD-L1) on antigen presenting cells in leprosy patients. CONCLUSION: This study point out a shift in our understanding of the immunological features that mediate and regulate the immune suppression and the disease progression in leprosy patients with a new paradigm (IL-35 producing Tregs and Bregs) that is beyond TGF-ß and IL-10 producing Treg cells.


Assuntos
Antígenos de Bactérias/imunologia , Linfócitos B Reguladores/imunologia , Interleucinas/imunologia , Hanseníase/imunologia , Mycobacterium leprae/imunologia , Linfócitos T Reguladores/imunologia , Adolescente , Adulto , Linfócitos B Reguladores/metabolismo , Linfócitos B Reguladores/patologia , Feminino , Humanos , Interleucinas/sangue , Hanseníase/sangue , Hanseníase/patologia , Masculino , Pessoa de Meia-Idade , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia
18.
Int J Biol Macromol ; 96: 161-170, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27956097

RESUMO

Human calcium/calmodulin-dependent protein kinase IV (CAMKIV), a member of Ser/Thr kinase family, is associated with cancer, cerebral hypoxia and neurodegenerative diseases. ß-carotene is a colored organic compound, abundant in plants and fruits and is used in cancer prevention. Here, we report a strong binding affinity of ß-carotene with CAMKIV using molecular docking, fluorescence binding and isothermal titration calorimetry methods. Furthermore, ß-carotene also reduces the enzyme activity of CAMKIV moderately as observed during ATPase assay. To see the role of ß-carotene on cell proliferation and apoptosis, cancerous cells (HeLa, HuH7and MCF-7) and normal (HEK-293-T) cell lines were used. Admirable anticancer activity of ß-carotene was observed. We further performed propidium iodide and DAPI (4',6-diamidino-2-phenylindole) assays to understand the mechanism of anticancer activity of ß-carotene at molecular level. Our findings provide a newer insight into the use of ß-carotene in cancer prevention and protection via inhibition of CAMKIV by regulating the signaling pathways.


Assuntos
Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , beta Caroteno/metabolismo , beta Caroteno/farmacologia , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Conformação Proteica , Transdução de Sinais/efeitos dos fármacos
19.
Chem Biol Drug Des ; 89(5): 741-754, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27809417

RESUMO

Calcium/calmodulin-dependent protein kinase IV (CAMKIV) is a multifunctional Ser/Thr kinase, associated with cerebral hypoxia, cancer, and neurodegenerative diseases. Here, we report design, synthesis, and biological evaluation of seven pyrimidine-substituted novel inhibitors of CAMKIV. We successfully synthesized and extensively characterized (ESI-MS, 1 H NMR, and 13 C NMR studies) seven compounds that are showing appreciable binding affinity to the CAMKIV. Molecular docking and fluorescence binding studies revealed that compound 1 is showing very high binding free energy (ΔG = -11.52 kcal/mol) and binding affinity (K = 9.2 × 1010 m-1 ) to the CAMKIV. We further performed MTT assay to check the cytotoxicity and anticancer activity of these compounds. An appreciable IC50 (39 µm) value of compound 1 was observed on human hepatoma cell line and nontoxic till the 400 µm on human embryonic kidney cells. To ensure anticancer activity of all these compounds, we further performed propidium iodide assay to evaluate cell viability and DNA content during the cell cycle. We found that compound 1 is again showing a better anticancer activity on both human hepatoma and human embryonic kidney cell lines.


Assuntos
Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Inibidores de Proteínas Quinases/síntese química , Pirimidinas/química , Sítios de Ligação , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Estrutura Terciária de Proteína , Pirimidinas/metabolismo , Pirimidinas/farmacologia , Espectrometria de Fluorescência
20.
J Ayurveda Integr Med ; 7(1): 38-43, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27297508

RESUMO

BACKGROUND: The search for an ideal and new antiulcer drug has been extended to herbals for novel molecules that decrease the incidence of relapse and afford better protection. OBJECTIVE: The present study was designed to investigate the protective effect of hydro-alcoholic extract of Ruta graveolens (RGE) Linn. leaves on indomethacin (IND) and pylorus ligation-induced gastric ulcer in Wistar rats. MATERIALS AND METHODS: The rats of all the six groups were deprived of food for 24 h. Then, the first group received 1 ml/kg/day p.o. of 1% carboxymethylcellulose calcium (CMC), second group 1 ml/kg/day p.o. of 1% CMC and third group 20 mg/kg/day p.o. of IND. Fourth and fifth groups received RGE 200 and 400 mg/kg/day p.o., respectively; while the sixth group 10 mg/kg/day p.o. omeprazole. After 30 min, last three groups received 20 mg/kg/day p.o. of IND also. All these treatments after food deprivation were repeated each day for 5 consecutive days. Pylorus ligation was performed on 6th day in last five groups. After 4 h, stomach by sacrifice of the rats was examined for ulcer index (UI) and gastric mucus. Gastric juice was assessed for acidity, pH and pepsin; while gastric tissues were assessed for thiobarbituric acid reactive substance (TBARS) and glutathione (GSH). RESULTS: Fifth group showed significant decrease in UI (10.33 ± 0.67), TBARS (0.33 ± 0.03 mmol/mg), free acidity (48.78 ± 5.12 meq/l/100 g), total acidity (99.33 ± 9.31 meq/l/100 g), and pepsin activity (8.47 ± 0.41 µg/ml) levels while it showed significant increase in mucus (412.4 ± 21.6 µg/g), GSH (57.9 ± 4.8 mmol/mg) and pH (3.32 ± 0.27) compared to third group. Percent protection in RGE 400 mg was found to be 63.32 compared to indomethacin. CONCLUSION: RGE possesses antiulcerogenic activity as it exhibits protective effect on gastric ulcer in rats.

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