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1.
Plants (Basel) ; 12(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37765339

RESUMO

Chickpea is widely grown in rainfed areas of developing countries because of its nutritional abundance and adaptability. To overcome the environmental effect of drought on yield, a characteristic-linked selection strategy is proved as well-thought-out and advantageous for the development of drought-tolerant cultivars. To precisely understand the contribution of various physio-biochemical and yield-attributing traits toward drought tolerance in chickpea (Cicer arietinum L.), forty chickpea genotypes were evaluated in the years 2020-2021 and 2021-2022 under normal irrigated as well as drought-stressed conditions. Among the studied genotypes, genotype ICC4958 retained the highest chl content (0.55 mg g-1 FW), minimal electrolyte leakage, and superoxide dismutase (1.48 U/mg FW) and peroxidase (2.21 µmol/min/g FW) activities while cultivar JG11 maintained the maximum relative water content and proline accumulation. The principal-component-based biplots prioritized the physio-biochemical and yield-accrediting characteristics based on their association significance and contribution to terminal drought tolerance. Under drought stress, grain yield per plant was depicted to have a strongly positive association with canopy temperature depression, catalase, superoxide dismutase, and peroxidase activities as well as total soluble sugar, proline, and chlorophyll content, along with the numbers of pods and biological yield per plant. These identified physio-biochemical and yield-attributing traits can be further deployed to select drought-tolerant chickpea genotypes for the breeding of climate-smart chickpea genotypes.

2.
Viral Immunol ; 36(8): 495-502, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37643285

RESUMO

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) stimulates the plasma B cells to secrete specific antibodies against the viral antigen. However, not all antibodies can prevent the virus from entering the cells. The subpopulation of antibodies which blocks the entry of the virus into host cells is termed neutralizing antibodies (NAbs). The gold standard test for the detection of NAbs is the viral plaque reduction and neutralization test; however, various other methods can also be utilized to detect NAbs. In this study, we have developed an Enzyme Linked Immunosobent Assay (ELISA)-based protocol for rapid detection of SARS CoV-2 NAb by inhibiting the binding of the spike protein receptor-binding domain to angiotensin converting enzyme 2 and compared it with cPASS neutralizing antibody kit, which was approved by the Food and Drug Administration (FDA). The results obtained suggest that the in-house ELISA developed for the detection of NAbs against SARS-CoV-2 is rapid and reliable. Compared to FDA-approved GenScript's cPass assay, the specificity and the sensitivity of the in-house-developed ELISA kit were 100% (95% confidence intervals of 69.15-100.00) and 96% (95% confidence intervals of 86.29-99.51), respectively. Thus, the ELISA protocol developed to test the neutralizing activities of antibodies is rapid, which requires a BSL-2 infrastructure facility and can be easily performed. It has very high potential applications in the rapid screening of NAb against SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Anticorpos Antivirais , Anticorpos Neutralizantes , Ensaio de Imunoadsorção Enzimática , Glicoproteína da Espícula de Coronavírus/química
3.
Cureus ; 15(2): e34791, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36915844

RESUMO

Gitelman's syndrome (GS) is a disorder characterized by hypokalaemia, hypomagnesemia, hypocalciuric and metabolic alkalosis. Despite the fact that it affects women of child-bearing age, only limited information is available regarding its impact on maternal and foetal outcome. We present the case of an un-booked and un-investigated 23-year-old primigravida who presented with chief complaints of vomiting and loose stools. The patient also complained of absent foetal movements in the last 12 hours. Investigations revealed hypokalaemia and hypomagnesemia and ultrasound revealed intra-uterine foetal demise. The patient was symptomatically relieved after electrolyte correction. Scarce reports on Gitelman's syndrome in pregnancy have been documented with the majority of cases showing positive outcomes for the foetus. We hereby present a report of a primigravida with Gitelman's syndrome and foetal loss which is considered uncommon.

4.
Viral Immunol ; 35(4): 284-290, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35325564

RESUMO

Coronavirus disease 2019 (COVID-19) continuously affecting the lives of millions of people. The virus is spread through the respiratory route to an uninfected person, causing mild-to-moderate respiratory disease-like symptoms that sometimes progress to severe form and can be fatal. When the host is infected with the virus, both innate and adaptive immunity comes into play. The effector T cells act as the master player of adaptive immune response in eradicating the virus from the system. But during cancer and chronic viral infections, the fate of an effector T cell is altered, and the T cell may enters a state of exhaustion, which is marked by loss of effector function, depleted proliferative capacity and cytotoxic effect accomplished by an increased expression of numerous inhibitory receptors such as programmed cell death protein 1 (PD-1), lymphocyte-activation protein 3 (LAG-3), and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) on their surface. Various other transcriptional and epigenetic changes take place inside the T cell when it enters into an exhausted state. Latest studies point toward the induction of an abnormal immune response such as lymphopenia, cytokine storm, and T cell exhaustion during SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection. This review sheds light on the dysfunctional state of T cells during chronic viral infection and COVID-19. Understanding the cause and the effect of T cell exhaustion observed during COVID-19 may help resolve new therapeutic potentials for treating chronic infections and other diseases.


Assuntos
COVID-19 , Imunidade Adaptativa , Síndrome da Liberação de Citocina , Humanos , SARS-CoV-2 , Linfócitos T
5.
Immunopharmacol Immunotoxicol ; 44(2): 141-146, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35130792

RESUMO

Over the last twenty months, the attention of the world has been focusing on managing the unprecedented and devastating wave of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV 2) and mitigating its impacts. Recent findings indicated that high levels of pro-inflammatory cytokines are leading cause of poor prognosis in severely ill COVID-19 patients. Presently, the multiple variants and highly contagious nature of virus makes challenge humongous. The shortage and vaccine hesitancy also prompted to develop antiviral therapeutic agents to manage this pandemic. Nanocurcumin has potential antiviral activities and also beneficial in post COVID inflammatory complications. We have developed nanocurcumin based formulation using pyrroloquinoline quinone (PQQ) which protects cardio-pulmonary function and mitochondrial homeostasis in hypobaric hypoxia induced right ventricular hypertrophy in animal model and human ventricular cardiomyocytes. Nanocurcumin based formulation (NCF) with improved bioavailability, has proven several holistic therapeutic effects including myocardial protection, and prevents edema formation, anti-inflammatory and antioxidant properties, maintaining metabolic and mitochondrial homeostasis under hypoxic condition. The post COVID-inflammatory syndrome also reported to cause impaired heart function, lung injuries and increased C-reactive protein level in severely ill patients. Thus, we speculate that NCF could be a new treatment option to manage post COVID-19 inflammatory syndrome.


Assuntos
Tratamento Farmacológico da COVID-19 , Animais , Antioxidantes/farmacologia , Humanos , Hipóxia/tratamento farmacológico , Hipóxia/metabolismo , Mitocôndrias , Pandemias
7.
Biophys J ; 119(9): 1771-1780, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33086046

RESUMO

Mechanical forces between cells and their microenvironment critically regulate the asymmetric morphogenesis and physiological functions in vascular systems. Here, we investigated the asymmetric cell alignment and cellular forces simultaneously in micropatterned endothelial cell ring-shaped sheets and studied how the traction and intercellular forces are involved in the asymmetric vascular morphogenesis. Tuning the traction and intercellular forces using different topographic geometries of symmetric and asymmetric ring-shaped patterns regulated the vascular asymmetric morphogenesis in vitro. Moreover, pharmacologically suppressing the cell traction force and intercellular force disturbed the force-dependent asymmetric cell alignment. We further studied this phenomenon by modeling the vascular sheets with a mechanical force-propelled active particle model and confirmed that mechanical forces synergistically drive the asymmetric endothelial cell alignments in different tissue geometries. Further study using mouse diabetic aortic endothelial cells indicated that diseased endothelial cells exhibited abnormal cell alignments, traction, and intercellular forces, indicating the importance of mechanical forces in physiological vascular morphogenesis and functions. Overall, we have established a controllable micromechanical platform to study the force-dependent vascular asymmetric morphogenesis and thus provide a direct link between single-cell mechanical processes and collective behaviors in a multicellular environment.


Assuntos
Células Endoteliais , Fenômenos Mecânicos , Animais , Fenômenos Biomecânicos , Camundongos , Morfogênese , Estresse Mecânico
8.
Int J Med Mushrooms ; 22(6): 547-558, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32865896

RESUMO

This study was designed to understand the effect of extraction temperature, i.e., room temperature (GLRT), 50°C (GL50), 100°C (hot water; GL100), and 200°C (GL200) on antioxidant and biological activity of G. lucidum. The % yield obtained was 5.3%, 7.6%, 10.7%, and 13.2% at various extraction temperatures; room temperature, 50°C, 100°C and 200°C, respectively. Similarly, phenolic content (51.6, 57.9, 82.9, and 93.1 mg/g extract) and flavonoid content (18.8, 23.2, 34.3, and 36.3 mg/g extract) were observed to be increased with rise in extraction temperature. However, extraction temperature resulted in loss of antioxidant activities above 100°C as evident by chemical assays such as DPPH, FRAP, ABTS, and TRP conducted on extracts. In contrast, three bioactive compounds, i.e., adenine (3.26, 3.48, 2.16, and 1.45 mg/g extract), uracil (3.99, 3.21, 2.51, and 1.47 mg/g extract), and adenosine (5.92, 5.62, 2.22 and 0.7 mg/g extract), quantified by high performance thin layer chromatography showed decrease in their content with increasing extraction temperature. Extract prepared at room temperature and 50°C prevented loss of cell viability and generation of reactive oxygen species resulted after hydrogen peroxide exposure; however, cytoprotective efficacy was not significant at 100°C and 200°C The order of cytoprotective effects observed by these extract were in the following order: room temperature ≥ 50°C > 100°C > 200°C. Overall, the optimal temperature conditions for the efficient extraction of G. lucidum with water retaining bioactive compounds and biological activity was found to be below 100°C.


Assuntos
Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Citoproteção , Estresse Oxidativo , Reishi/química , Adenina/análise , Adenosina/análise , Animais , Morte Celular , Linhagem Celular , Flavonoides/análise , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/toxicidade , Camundongos , Fenóis/análise , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Temperatura , Uracila/análise
9.
Cell Stress Chaperones ; 25(3): 427-440, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32144684

RESUMO

Activator protein-1 (AP-1) plays a decisive role in cell proliferation, apoptosis, and inflammation under hypoxia; thus, AP-1 subunits or dimers could be modulated for a desired phenomenon in a cell using a suitable compound of therapeutic potential. Herein, we used Tanshinone-IIA as an AP-1 (subunits) modulator, and the purpose of the study was to investigate the signaling mechanism exhibited by Tan-IIA in facilitating tolerance to hypoxia. A549 cells were pretreated with Tan-IIA and exposed to hypoxia for 6, 12, 24, and 48 h. Biochemical and molecular parameters were assessed in order to trace the signaling pathway. Tan-IIA attenuated hypoxia-induced oxidative stress by modulating the expression of AP-1 subunits (via. MAPK) and Nrf2 transcription factor, which in turn were responsible for maintaining the higher levels of antioxidant enzymes and genes (HO). Tan-IIA increased the cell survival. This could be attributed to an increased NO level via iNOS gene and activated JNK, ERK pathway that induced c-jun/c-fos, c-jun/fosB, junD/c-fos, and junD/fosB heterodimers. This in turn leads to the cell cycle progression by activating cyclins (D and B). This was further confirmed by the lower levels of p53 and their downstream genes (p16, p21, p27). In addition, Tan-IIA decreased pro-inflammatory cytokine levels by inhibiting the formation of junB/fra-1 heterodimer regulated by p38. Tan-IIA increased cell survival to hypoxia by maintaining the higher levels of cellular iNOS, HO-1, jun-D, c-jun, fos B via Nrf2-AP-1.


Assuntos
Abietanos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Fator de Transcrição AP-1/metabolismo , Células A549 , Cálcio/metabolismo , Ciclo Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteínas Inibidoras de Quinase Dependente de Ciclina/metabolismo , Ciclinas/metabolismo , Citocinas/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
10.
Environ Res ; 184: 109253, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32145548

RESUMO

The practice of hair dyeing is a rapidly expanding industry on a global scale; however, it has become a major concern for Asian countries because they have been undergoing rapid transformations of their environment and lifestyles. While the socio-economic benefits and impacts of this globalization trend are widely understood, the environmental effects are largely unknown. In particular, commonly available oxidative dyes potentially pose specific environmental risks due to their use of a toxic aromatic amine p-Phenylenediamine (PPD). In investigating the environmental impacts of PPD chemicals, we first provide context to the study by setting out the socio-psychological drivers to industrial expansion in Asian countries along with an overview of research into its effects, to show that its environmental impacts are under-researched. We then investigate the environmental toxicity of PPD by focusing on the role of microbes in metabolizing waste products. Results show that Acinetobacter baumannii EB1 isolated from dye effluent prevents autoxidation of PPD under oxygen-enriched (shaking) or oxygen-deficient (static) conditions representing different environmental settings. Microbes transformed PPD into more toxic metabolites, which then significantly reduced plant growth, thereby having a direct bearing on ecosystem services. Based on the findings, we argue that stricter regulatory controls on hair dye wastewater are necessary, particularly in newly industrialising Asian countries where the expansion of commercial practice is most prevalent.


Assuntos
Tinturas para Cabelo , Estilo de Vida , Águas Residuárias , Poluentes Químicos da Água , Ásia , Ecossistema , Tinturas para Cabelo/toxicidade , Humanos , Fenilenodiaminas/toxicidade , Águas Residuárias/química , Poluentes Químicos da Água/toxicidade
11.
JNMA J Nepal Med Assoc ; 57(219): 352-356, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32329463

RESUMO

INTRODUCTION: Many vision threatening or life threatening neoplastic conditions often mimic less aggressive neoplastic or non-neoplastic inflammatory variants. This study aims to comprehensively analyze the histopathological spectrum of ophthalmic neoplastic lesions tumors in a pathology laboratory in a tertiary care hospital. METHODS: A descriptive cross-sectional study was conducted in the Department of Pathology at Birat Medical College and Teaching Hospital, Morang, Nepal over a period from November 2016 to October 2018. Ethical clearance was taken from Institutional Review Committee of Birat Medical College. Sample size was calculated and convenience sampling was done. Data was collected in excel and analyzed in Statistical Package for Social Sciences version 16. Point estimate at 95% Confidence Interval was calculated and frequency and percentage was calculated for binary data. Subgroup analysis was done based on age, sex, nature of lesions and site of lesions. RESULTS: Prevalence of ophthalmic neoplastic lesion was 139 (55.37%), of which 74 (53.24%) were benign and 65 (46.76%) were malignant. Benign was mostly seen in females and of second decade and malignant was common in males and seventh decade of life respectively. Nevus in 18 (24.3%) and squamous cell carcinoma in 30 (17.6%) was found to be the most common benign and malignant lesions among the specimens. Conjunctiva and cornea in 52 (37.41%) was the most common location for those neoplastic lesions. CONCLUSIONS: The most common ophthalmic neoplastic lesion was benign. Nevus is common in females and second decade and squamous cell carcinoma is common in males and seventh decade of life.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias Oculares/diagnóstico , Nevo/diagnóstico , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Criança , Pré-Escolar , Estudos Transversais , Neoplasias Oculares/epidemiologia , Neoplasias Oculares/patologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Nepal , Nevo/epidemiologia , Nevo/patologia , Prevalência , Distribuição por Sexo , Centros de Atenção Terciária , Adulto Jovem
12.
J Cell Physiol ; 233(10): 6851-6865, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29665093

RESUMO

This study reports the role of MAPKs (JNK, ERK, and p38), and activator protein-1 (AP-1) transcription factor in the hypobaric hypoxia induced change in lung tissue. Healthy male Sprague-Dawley rats were exposed to hypobaric hypoxia for 6, 12, 24, 48, 72, and 120 hr. Hypoxia resulted in significant increase in reactive oxygen species (ROS), vascular endothelial growth factor (VEGF) and decreased nitric oxide (NO), these act as signaling molecules for activation of MAPK and also contribute in development of vascular leakage (an indicator of pulmonary edema) as confirmed by histological studies. Our results confirmed JNK activation as an immediate early response (peaked at 6-48 hr), activation of ERKs (peaked at 24-72 hr) and p38 (peaked at 72-120 hr) as a secondary response to hypoxia. The MAPK pathway up regulated its downstream targets phospho c-Jun (peaked at 6-120 hr), JunB (peaked at 24-120 hr) however, decreased c-Fos, and JunD levels. DNA binding activity also confirmed activation of AP-1 transcription factor in lung tissue under hypobaric hypoxia. Further, we analyzed the proliferative and inflammatory genes regulated by different subunits of AP-1 to explore its role in vascular leakage. Increased expression of cyclin D1 (peaked at 12-72 hr) and p16 level (peaked at 48-120 hr) were correlated to the activation of c-jun, c-Fos and JunB. Administration of NFκB inhibitor caffeic acid phenethyl ester (CAPE) and SP600125 (JNK inhibitor) had no effect on increased levels of Interferon-γ (IFN-γ), Interleukin-1 (IL-1), and Tumor Necrosis Factor-α (TNF-α) thereby confirming the involvement of AP-1 as well as NFκB in inflammation. Expression of c-jun, c-Fos were correlated with activation of proliferative genes and JunB, Fra-1 with pro-inflammatory cytokines. In conclusion immediate response to hypobaric hypoxia induced c-Jun:c-Fos subunits of AP-1; responsible for proliferation that might cause inhomogeneous vasoconstriction leading to vascular leakage and inflammation at increased duration of hypobaric hypoxia exposure.


Assuntos
Hipóxia/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Fator de Transcrição AP-1/metabolismo , Ativação Transcricional/fisiologia , Animais , Humanos , Pulmão/metabolismo , Masculino , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Mol Cell Biochem ; 436(1-2): 99-110, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28589371

RESUMO

Activator protein-1 (AP-1) transcription factor plays a central role in hypoxia to modulate the expression of genes that decides the fate of the cell. The aim of the present study was to explore the role of AP-1 subunits in lung epithelial (A549) cells under hypoxia. Cell cycle studies by flow cytometry indicated that cell viability was unaffected by the initial hypoxia exposure (0.5% O2 at 37 °C) for 6 and 12 h. However, both transient cell cycle arrest and cell death was detected at 24 and 48 h. Flow cytometry and spectrofluorometry data confirmed the increase in ROS levels. Elevated ROS and calcium levels activated the stress-related MAPK signaling cascade. ERK and JNK were activated in early hypoxic exposure (within 6 h), whereas p38 were activated in 48 h of hypoxia. These subtypes further stimulated the subunits of AP-1 at different times of hypoxia exposure to orchestrate different genes responsible for cell proliferation (6 and 12 h) and apoptosis (24 and 48 h). Our results clearly depict the role of AP-1 heterodimer, i.e., p-c-jun/c-fos, p-c-jun/fosB, junD/c-fos, and junD/fosB in cell proliferation/survival by regulating the expression of Bcl-2 and cyclins (D1 and B1) at 6 h and 12 h of hypoxia, whereas junB/Fra-1 heterodimer have important role in apoptosis by regulating the expression of p53, Bax, and cyclin-dependent kinase inhibitors (p16, p21, p27) at 24 h and 48 h of hypoxia. Also, the cell survival signaling pathway NO-AKT interrupted at 24 h and 48 h of hypoxia indicating cell death. In conclusion, hypoxia for different time points activated different subunits of AP-1 that combined to form different heterodimers. These dimers regulated the expression of genes responsible for cell proliferation and apoptosis. Since, AP-1 plays a role in the decisive phenomenon of the cell to choose between proliferation and apoptosis; thus, its subunits or dimers could be a good therapeutic target for many diseases.


Assuntos
Células Epiteliais Alveolares/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Pontos de Checagem do Ciclo Celular , Sistema de Sinalização das MAP Quinases , Fator de Transcrição AP-1/metabolismo , Células A549 , Células Epiteliais Alveolares/citologia , Proteínas Reguladoras de Apoptose/genética , Hipóxia Celular , Humanos
14.
Mol Biol Rep ; 41(10): 6537-43, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25001590

RESUMO

Interferon gamma (IFN-γ) is an important immunoregulatory cytokine that has a central role against viral and bacterial infections. In this study, the cDNA encoding 141 amino acids of mature IFN-γ from mice splenocytes was cloned in a prokaryotic expression vector pQE 30. Optimization of expression conditions resulted in high IFN-γ protein. Western blot showed that recombinant IFN-γ was specifically recognized by its counterpart anti-mouse IFN-γ antibodies. In vitro dose-dependent studies, with A549 and HeLa cell lines, showed that cloned IFN-γ was safe and had no effect on cell proliferation. The protein prediction and analysis using SOPMA program, revealed that IFN-γ had 80 α-helices, 8 ß-turns jointed by 9 extended strands and 44 random coils. A total of four major clusters were observed with murine IFN-γ sharing 39 % homology with human IFN-γ. Pair-wise alignment studies with human revealed 26 % identity and 43.3 % similarity. The recovery of bioactive proteins from inclusion bodies (IBs) is a complex process and various protocols have been developed. We report here a simple, robust and inexpensive purification approach for obtaining recombinant IFN-γ protein expressed as IBs in E.coli.


Assuntos
Escherichia coli/genética , Expressão Gênica , Interferon gama/genética , Proteínas Recombinantes/genética , Sequência de Aminoácidos , Animais , Linhagem Celular , Humanos , Interferon gama/química , Interferon gama/isolamento & purificação , Interferon gama/farmacologia , Camundongos , Dados de Sequência Molecular , Filogenia , Plasmídeos/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Alinhamento de Sequência , Análise de Sequência de DNA
15.
Indian J Hum Genet ; 20(1): 4-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24959008

RESUMO

Oral cancers have been one of the leading causes of deaths particularly in the developing countries. Prime reason for this high mortality and morbidity is attributed to the delay in diagnosis and prompt treatment. Relentless research in the field of oncology has led to the advent of novel procedures for the early detection of oral cancers. Molecular biology is highly promising in this regard. It is a procedure that detects alterations at a molecular level much before they are seen under a microscope and much before clinical changes occur. Molecular studies serve as the basis by which we will eventually be able not only to augment clinical assessment and classification of oral lesions but also predict malignant potential of oral lesions, thus reducing the incidence and increasing the scope for early diagnosis and treatment of oral cancers. However, making such sophisticated tools available for the common man in developing countries is one of the most important challenges faced today.

16.
PLoS One ; 9(6): e98025, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24887065

RESUMO

BACKGROUND: The physiological challenges posed by hypobaric hypoxia warrant exploration of pharmacological entities to improve acclimatization to hypoxia. The present study investigates the preclinical efficacy of sphingosine-1-phosphate (S1P) to improve acclimatization to simulated hypobaric hypoxia. EXPERIMENTAL APPROACH: Efficacy of intravenously administered S1P in improving haematological and metabolic acclimatization was evaluated in rats exposed to simulated acute hypobaric hypoxia (7620 m for 6 hours) following S1P pre-treatment for three days. MAJOR FINDINGS: Altitude exposure of the control rats caused systemic hypoxia, hypocapnia (plausible sign of hyperventilation) and respiratory alkalosis due to suboptimal renal compensation indicated by an overt alkaline pH of the mixed venous blood. This was associated with pronounced energy deficit in the hepatic tissue along with systemic oxidative stress and inflammation. S1P pre-treatment improved blood oxygen-carrying-capacity by increasing haemoglobin, haematocrit, and RBC count, probably as an outcome of hypoxia inducible factor-1α mediated erythropoiesis and renal S1P receptor 1 mediated haemoconcentation. The improved partial pressure of oxygen in the blood could further restore aerobic respiration and increase ATP content in the hepatic tissue of S1P treated animals. S1P could also protect the animals from hypoxia mediated oxidative stress and inflammation. CONCLUSION: The study findings highlight S1P's merits as a preconditioning agent for improving acclimatization to acute hypobaric hypoxia exposure. The results may have long term clinical application for improving physiological acclimatization of subjects venturing into high altitude for occupational or recreational purposes.


Assuntos
Aclimatação/efeitos dos fármacos , Hipóxia/sangue , Hipóxia/metabolismo , Lisofosfolipídeos/farmacologia , Esfingosina/análogos & derivados , Animais , Biomarcadores/sangue , Eletrólitos/metabolismo , Metabolismo Energético/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hipóxia/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Rim/fisiopatologia , Lactatos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/sangue , Ratos Sprague-Dawley , Receptores de Lisoesfingolipídeo/metabolismo , Esfingosina/farmacologia
17.
Lipids ; 49(2): 191-202, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24190514

RESUMO

Sphingosine-1-phosphate (S1P), a biologically active pleiotropic lipid, is involved in several physiological processes especially in the area of vascular biology and immunology encompassing cell survival, angiogenesis, vascular tone, immune response etc. by interacting with specific cell surface receptors. Hypoxia, a condition common to innumerable pathologies, is known to lethally affect cell survival by throwing off balance global gene expression, redox homeostasis, bioenergetics etc. Several molecular events of cellular adaptations to hypoxia have been closely linked to stabilization of hypoxia inducible factor-1α (HIF-1α). Signalling functions of S1P in physiological events central to hypoxia-induced pathologies led us to investigate efficacy of exogenous S1P in preconditioning murine splenocytes to sustain during cellular stress associated with sub-optimal oxygen. The present study recapitulated the pro-survival benefits of exogenous S1P under normobaric hypoxia. Results indicate a direct effect of S1P supplementation on boosting cellular adaptive responses via HIF-1α stabilization and, activation of pro-survival mediators ERK and Akt. Overwhelming anti-oxidative and anti-inflammatory benefits of S1P preconditioning could also be captured in the present study, as indicated by improved redox homeostasis, reduced oxidative damage, balanced anti/pro-inflammatory cytokine profiles and temporal regulation of nitric oxide secretion and intra-cellular calcium release. Hypoxia induced cell death and the associated stress in cellular milieu in terms of oxidative damage and inflammation could be alleviated with exogenous S1P preconditioning.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/tratamento farmacológico , Lisofosfolipídeos/uso terapêutico , Esfingosina/análogos & derivados , Baço/citologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/imunologia , Hipóxia/imunologia , Hipóxia/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Esfingosina/uso terapêutico
18.
Immunol Cell Biol ; 91(10): 642-51, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24145856

RESUMO

Recombinant DNA vaccines represent a novel method for generating in situ expression of vaccine antigens. Intramuscular injections of naked DNA are able to elicit potent humoral and cellular immune responses but still numerous factors limit the immunogenicity of DNA vaccines. Co-expression of cytokines with antigen encoding genes in DNA vectors can improve the immune responses and modify Th1/Th2 balance. In this study, the immunomodulatory effect of Interleukin 22 (IL-22) as an adjuvant was studied by DNA vaccination with S. Typhi Heat shock protein 60 (HSP60/GroEL) in mice. Further, DNA construct of IL-22 gene fused with GroEL was developed and immunization studies were carried out in mice. DNA vaccination with GroEL alone stimulated humoral and cell-mediated immune responses. Co-immunization (IL-22+GroEL) further resulted in increase in T-cell proliferative responses, antibody titres (IgG, IgG1, IgG2a) and secretion of IFNγ (Th1), IL-1ß and Th2 (IL-4, IL-6) cytokines. Co-expression (IL-22-GroEL DNA) also promoted antibody titres and cytokine levels were significantly higher as compared to co-immunized group. A reduction in bacterial load in spleen, liver and intestine was seen in all the immunized groups as compared to control, with least organ burden in fusion DNA construct group (co-expression). Improved protective efficacy (90%) against lethal challenge by Salmonella was observed with IL-22-GroEL co-expressing DNA vector as compared with plasmid encoding GroEL only (50-60%) or co-immunization group (75-80%). This study thus shows that co-expression of IL-22 and GroEL genes enhances the immune responses and protective efficacy, circumventing the need of any adjuvant.


Assuntos
Chaperonina 60/genética , Imunidade/genética , Interleucinas/genética , Salmonelose Animal/genética , Salmonelose Animal/imunologia , Animais , Formação de Anticorpos/imunologia , Carga Bacteriana/imunologia , Proliferação de Células , Citocinas/metabolismo , DNA Recombinante/genética , DNA Recombinante/uso terapêutico , Feminino , Expressão Gênica , Vetores Genéticos/metabolismo , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/biossíntese , Biossíntese de Proteínas , Salmonelose Animal/tratamento farmacológico , Salmonelose Animal/prevenção & controle , Linfócitos T/citologia , Linfócitos T/imunologia , Transcrição Gênica , Resultado do Tratamento , Vacinas de DNA/imunologia , Vacinas de DNA/uso terapêutico , Interleucina 22
19.
Biomed Res Int ; 2013: 569206, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24063008

RESUMO

Cordyceps sinensis, an edible mushroom growing in Himalayan regions, is widely recognized in traditional system of medicine. In the present study, we report the efficacy of Cordyceps sinensis in facilitating tolerance to hypoxia using A549 cell line as a model system. Treatment with aqueous extract of Cordyceps sinensis appreciably attenuated hypoxia induced ROS generation, oxidation of lipids and proteins and maintained antioxidant status similar to that of controls via induction of antioxidant gene HO1 (heme oxygenase-1), MT (metallothionein) and Nrf2 (nuclear factor erythroid-derived 2-like 2). In contrast, lower level of NF κ B (nuclear factor kappaB) and tumor necrosis factor- α observed which might be due to higher levels of HO1, MT and transforming growth factor- ß . Further, increase in HIF1 (hypoxia inducible factor-1) and its regulated genes; erythropoietin, vascular endothelial growth factor, and glucose transporter-1 was observed. Interestingly, Cordyceps sinensis treatment under normoxia did not regulate the expression HIF1, NF κ B and their regulated genes evidencing that Cordyceps sinensis per se did not have an effect on these transcription factors. Overall, Cordyceps sinensis treatment inhibited hypoxia induced oxidative stress by maintaining higher cellular Nrf2, HIF1 and lowering NF κ B levels. These findings provide a basis for possible use of Cordyceps sinensis in tolerating hypoxia.


Assuntos
Adaptação Fisiológica , Cordyceps/química , Células Epiteliais/enzimologia , Heme Oxigenase-1/biossíntese , Pulmão/patologia , Metalotioneína/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Antioxidantes/análise , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Misturas Complexas/farmacologia , Citoproteção/efeitos dos fármacos , Indução Enzimática/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Flavonoides/análise , Glutationa/metabolismo , Humanos , Fator 1 Induzível por Hipóxia/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , NF-kappa B/metabolismo , Oxirredução/efeitos dos fármacos , Fenóis/análise , Espécies Reativas de Oxigênio/metabolismo
20.
Appl Biochem Biotechnol ; 169(8): 2405-19, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23456277

RESUMO

We examined the effect of subchronic hypobaric hypoxia in rat heart. Adult male Sprague-Dawley rats were exposed at 25,000 ft for different time periods (2 and 5 days). Susceptibility of their hearts to oxidative stress as well as modulation in gene expression was evaluated. The results showed a crosstalk between reactive oxygen species (ROS) and nitric oxide (NO), initial response was accompanied by increase in ROS generation and development of oxidative stress as confirmed by increased lipid peroxidation, protein oxidation and accumulation of 2, 4-dinitrophenyl hydrazine and 4-hydroxy-2-nonenal adducts. At the same time, glutathione activity decreased; however, antioxidant enzymatic activities of superoxide dismutases, glutathione-S-transferase, and glutathione peroxidase rose in response to 5-days hypoxia. Interestingly, NO level increased till 5 days, however ROS decreased after 5 days; this observation suggests that ROS/NO balance plays an important role in cardioprotection. This observation is further supported by upregulation of antioxidant genes hemeoxygenase (HO-1) and metallothionein (MT). In addition, hypoxia also induces gradual upregulation of hypoxia-inducible transcription factor (HIF-1α), which in turn induces the expression of adaptive genes erythropoiesis, vascular endothelial growth factor, glucose transporter-1, nitric oxide synthase. Collectively, our data suggests a reciprocal regulation of ROS and NO and this effect is mediated by the increase in antioxidant proteins HO-1 and MT. Along with this HIF-1-mediated induction of various cardioprotective genes also plays an important role in acclimatization.


Assuntos
Coração/fisiologia , Hipóxia/fisiopatologia , Estresse Oxidativo/fisiologia , Animais , Antioxidantes/metabolismo , Masculino , Metalotioneína/metabolismo , Miocárdio/metabolismo , Ratos , Ratos Sprague-Dawley
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