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2.
Pediatr Hematol Oncol ; 30(6): 537-43, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23756088

RESUMEN

Cell-free Epstein-Barr viral (EBV) DNA is detectable in plasma of patients with EBV-related lymphomas. The aim of this study was to evaluate the utility of plasma EBV DNA as a biomarker of EBV association in childhood Hodgkin lymphoma (HL). Furthermore, an attempt was made to evaluate the effectiveness of viral quantitation for assessing response to chemotherapy. Thirteen cases of childhood HL were included in this study. All 13 cases were EBV associated as reflected by expression of EBV LMP1 in the tumor specimen. Eighty-five percent had detectable EBV DNA levels; viral loads ranging from 2.9 to 156.2 × 10³ copies/ml (mean 29 × 10³ copies/ml); while in 2 patients and 30 controls tested, viral DNA was undetectable. In four patients, follow-up samples were available after three cycles of chemotherapy; all had EBV DNAemia prior to chemotherapy but undetectable EBV DNA posttherapy. This corroborated with complete response in these four patients. Plasma EBV viral load quantification maybe a useful tool for detecting EBV association with lymphomas and in monitoring response to treatment in childhood HL in centers with limited resources, more so in India where majority of childhood HL is likely to be EBV associated. This is the first Indian study estimating plasma EBV viral loads in HL.


Asunto(s)
ADN Viral/sangre , Infecciones por Virus de Epstein-Barr/sangre , Herpesvirus Humano 4/metabolismo , Enfermedad de Hodgkin/sangre , Enfermedad de Hodgkin/virología , Carga Viral , Adolescente , Niño , Preescolar , Infecciones por Virus de Epstein-Barr/terapia , Femenino , Enfermedad de Hodgkin/terapia , Humanos , India , Lactante , Masculino , Estudios Prospectivos , Proteínas de la Matriz Viral/metabolismo
3.
Immunobiology ; 225(3): 151907, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32044149

RESUMEN

Epstein Barr Viral infection is a common childhood infection in India and is also nearly 100 % etiologically associated with pediatric Hodgkin Lymphoma (HL). The main question in EBV immunobiology has been, why only a small subset of infected individuals develop EBV associated malignancies, while the vast majority carry this virus asymptomatically for life. Natural Killer (NK) cells, with a phenotype of CD56dim CD16+ exhibit potent cytotoxicity towards both virus infected cells and transformed cells and hence have been considered to be crucial in preventing the development of symptomatic EBV infection and lymphoma. In order to get an insight into the various possible molecular aspects of NK cells, in the pathogenesis of both these EBV mediated diseases in children we studied the whole transcriptome of MACS sorted CD56dim CD16 + NK cells from four patients from each of the three groups of children viz. Infectious Mononucleosis (IM), HL and age matched controls by using a massively parallel sequencing approach. NK cells from both IM and HL had down-regulated innate immunity and chemokine signaling genes. While down-regulation of genes responsible for polarization of the secretory apparatus, activated NK cell signaling and MAP kinase signaling were exclusive to NK cells in patients with IM, in NK cells of HL, specifically, genes involved in extracellular matrix (ECM) - receptor interaction, cytokine-cytokine receptor interaction, TNF signaling, Toll-like receptor signaling pathway and cytosolic DNA-sensing pathways were significantly down-regulated. Enrichment analysis showed STAT3 to be the most significant transcription factor (TF) for the down-regulated genes in IM, whereas, GATA1 was found to be the most significant TF for the genes down-regulated in HL. Analysis of protein interaction network identified functionally important protein clusters. Top clusters, comprised of down-regulated genes, involved in signaling and ubiquitin-related processes and pathways. These may perhaps be responsible for the hypo-responsiveness of NK cells in both diseases. These possibly point to different deficiencies in NK cell activation, loss of activating receptor signaling and degranulation in IM, versus loss of cytokine and chemokine signaling in HL, in the two EBV associated pathologies investigated. Various suppressed molecules and pathways were novel, which have not been reported earlier and could therefore be potential targets for immunotherapy of NK cell reactivation in both the diseases in future.


Asunto(s)
Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/inmunología , Regulación Neoplásica de la Expresión Génica , Herpesvirus Humano 4 , Enfermedad de Hodgkin/etiología , Células Asesinas Naturales/metabolismo , Transcriptoma , Biomarcadores , Niño , Citocinas/genética , Citocinas/metabolismo , Susceptibilidad a Enfermedades , Infecciones por Virus de Epstein-Barr/virología , Femenino , Herpesvirus Humano 4/inmunología , Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedad de Hodgkin/diagnóstico , Humanos , Inmunidad Innata , Células Asesinas Naturales/inmunología , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Masculino , Transducción de Señal
4.
Amino Acids ; 36(3): 417-28, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18414974

RESUMEN

The present study has been carried out to investigate the role of taurine (2-aminoethanesulfonic acid), a conditionally essential amino acid, in ameliorating cadmium-induced renal dysfunctions in mice. Cadmium chloride (CdCl(2)) has been selected as the source of cadmium. Intraperitoneal administration of CdCl(2 )(at a dose of 4 mg/kg body weight for 3 days) caused significant accumulation of cadmium in renal tissues and lessened kidney weight to body weight ratio. Cadmium administration reduced intracellular ferric reducing/antioxidant power (FRAP) of renal tissues. Levels of serum marker enzymes related to renal damage, creatinine and urea nitrogen (UN) have been elevated due to cadmium toxicity. Cadmium exposure diminished the activities of enzymatic antioxidants, superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx) and glucose-6-phosphate dehydrogenase (G6PD) as well as non-enzymatic antioxidant, reduced glutathione (GSH) and total thiols. On the other hand, the levels of oxidized glutathione (GSSG), lipid peroxidation, protein carbonylation, DNA fragmentation, concentration of superoxide radicals and activities of cytochrome P450 enzymes (CYP P450s) have been found to increase due to cadmium intoxication. Treatment with taurine (at a dose of 100 mg/kg body weight for 5 days) before cadmium intoxication prevented the toxin-induced oxidative impairments in renal tissues. The beneficial role of taurine against cadmium-induced renal damage was supported from histological examination of renal segments. Vitamin C, a well-established antioxidant was used as the positive control in the study. Experimental evidence suggests that both taurine and vitamin C provide antioxidant defense against cadmium-induced renal oxidative injury. Combining all, results suggest that taurine protects murine kidneys against cadmium-induced oxidative impairments, probably via its antioxidative property.


Asunto(s)
Antioxidantes/administración & dosificación , Ácido Ascórbico/administración & dosificación , Cloruro de Cadmio/toxicidad , Enfermedades Renales/prevención & control , Estrés Oxidativo/efectos de los fármacos , Taurina/administración & dosificación , Animales , Fragmentación del ADN , Riñón/efectos de los fármacos , Riñón/patología , Enfermedades Renales/inducido químicamente , Enfermedades Renales/patología , Masculino , Ratones , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/fisiología
5.
Toxicology ; 257(1-2): 53-63, 2009 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-19133311

RESUMEN

Increasing evidences in both experimental and clinical studies suggest that oxidative stress is involved in the pathogenesis of diabetic tissue damage. Pancreatic beta-cell death is the cause of decreased insulin production in diabetes. Streptozotocin (STZ) is widely used to induce experimental diabetes due to its ability to selectively target and destroy insulin producing pancreatic beta-cells via the formation of both reactive oxygen species (ROS) and RNS (reactive nitrogen species). This study investigated the prophylactic role of arjunolic acid (AA) against STZ-induced diabetes in the pancreas tissue of the Swiss albino rats (as a working model). We observed that STZ administration (at a dose of 65mg/kg body weight, injected in the tail vain) caused increased production of both ROS and RNS in the pancreas tissue of experimental animals. Formation of these reactive intermediates decreased the intracellular antioxidant defense, increased the levels of lipid peroxidation, protein carbonylation, serum glucose and TNF-alpha. Investigating the signaling pathways, we found that STZ administration caused the activation of phospho-ERK1/2, phospho-p38, NF-kappaB and destruction of mitochondrial transmembrane potential, release of cytochrome c as well as activation of caspase 3 in the pancreas tissue keeping the levels of total ERK1/2 and p38 significantly unchanged. Treatment of animals with AA (at a dose of 20mg/kg body weight, orally) both prior and post to the STZ administration effectively reduced these adverse effects by inhibiting the excessive ROS and RNS formation as well as by down-regulating the activation of phospho-ERK1/2, phospho-p38, NF-kappaB and mitochondrial dependent signal transduction pathways leading to apoptotic cell death. Combining all, these results suggest that AA plays some beneficial roles against STZ-induced diabetes.


Asunto(s)
Antioxidantes/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemiantes/farmacología , Mitocondrias/efectos de los fármacos , Páncreas/efectos de los fármacos , Triterpenos/farmacología , Animales , Apoptosis/efectos de los fármacos , Glucemia/efectos de los fármacos , Caspasa 3/metabolismo , Citocromos c/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patología , Relación Dosis-Respuesta a Droga , Peroxidación de Lípido/efectos de los fármacos , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , FN-kappa B/metabolismo , Estrés Oxidativo/efectos de los fármacos , Páncreas/metabolismo , Páncreas/patología , Fosforilación , Carbonilación Proteica/efectos de los fármacos , Ratas , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factores de Tiempo , Factor de Necrosis Tumoral alfa/sangre , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
6.
Toxicol Lett ; 187(3): 201-10, 2009 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-19429265

RESUMEN

Arsenic (As) is a well known toxicity inducer. Recent investigations, however, showed that it might have some therapeutic application in cancer treatment. These dual roles of arsenic have attracted a renewed research in organ pathophysiology. In this study, we report that As administration (in the form of NaAsO(2) at a dose of 10mg/kg body weight for 2 days, orally) induces apoptosis in testicular tissue of the experimental rats by the activation of caspase-3 and reciprocal regulation of Bcl-2/Bad with the concomitant reduction of mitochondrial membrane potential and increased level of cytosolic cytochrome C. Arsenite has also been shown to induce activation of mitogen-activated protein kinases (MAPKs), Akt as well as NF-kappaB (p65) in testicular tissue. In addition, As significantly decreased testicular Delta(5)-3beta-HSD and 17beta-HSD activities and reduced the plasma testosterone level, testicular sperm count and sperm motility. Besides, arsenite exposure increased the levels of reactive oxygen species (ROS), serum TNF-alpha, As accumulation and lipid peroxidation and decreased the activities of the antioxidant enzymes and glutathione in the testicular tissue. Oral administration of taurine (at a dose of 100mg/kg body weight for 5 days) was found to be effective in counteracting As-induced oxidative stress, attenuation of testicular damages and amelioration of apoptosis in testicular tissue by controlling the reciprocal regulation of Bcl-2/Bad, phospho-ERK1/2, phospho-p38, phospho-Akt and NF-kappaB. Taurine was also found to play similar beneficial role via mitochondrial dependent pathways in As-induced testicular damages leading to apoptotic cell death.


Asunto(s)
Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Arsenitos/toxicidad , Mitocondrias/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Compuestos de Sodio/toxicidad , Taurina/farmacología , Enfermedades Testiculares/inducido químicamente , Animales , Interacciones Farmacológicas , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Ratas , Ratas Wistar , Recuento de Espermatozoides , Motilidad Espermática/efectos de los fármacos , Enfermedades Testiculares/metabolismo , Enfermedades Testiculares/patología , Enfermedades Testiculares/prevención & control , Testículo/efectos de los fármacos , Testículo/metabolismo , Testosterona/sangre , Testosterona/metabolismo , Factor de Necrosis Tumoral alfa/sangre
7.
Drug Chem Toxicol ; 32(2): 93-102, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19514944

RESUMEN

The present study was conducted to investigate whether the conditionally essential amino acid, taurine, could play any protective role against the potent neurotoxin arsenic (As)-induced oxidative impairment in the rat brain. Administration in the form of NaAsO(2) (at a dose of 10 mg/kg body weight for 2 days, orally), As increased the intracellular accumulation of metallic As, reactive oxygen species, and super oxide radicals. The toxin also augmented the extent of lipid peroxidation, protein carbonylation, and the levels of glutathione disulphide. Activities of the antioxidant enzymes, membrane-bound enzymes, acetylcholinesterase, and the levels of reduced glutathione, as well as total thiols, have been significantly decreased due to As exposure. Oral administration of taurine (at a dose of 100 mg/kg/body weight for 5 days) was found to be very effective in the prevention of As-induced oxidative impairment in the brain tissue of the experimental rats. To validate the experimental results, a well-known water-soluble antioxidant, vitamin C, was used as the positive control in the study. Combining all, results suggest that taurine plays a beneficial role against As-induced cerebral oxidative stress.


Asunto(s)
Antioxidantes/uso terapéutico , Intoxicación por Arsénico/tratamiento farmacológico , Arsénico/toxicidad , Encéfalo/efectos de los fármacos , Glutatión/metabolismo , Estrés Oxidativo/efectos de los fármacos , Taurina/uso terapéutico , Acetilcolinesterasa/metabolismo , Adenosina Trifosfatasas/metabolismo , Aminoácidos Esenciales , Animales , Apoptosis/efectos de los fármacos , Ácido Ascórbico/uso terapéutico , Encéfalo/enzimología , Encéfalo/metabolismo , Catalasa/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Depuradores de Radicales Libres/uso terapéutico , Glutatión Transferasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Oxidantes/toxicidad , Ratas , Especies Reactivas de Oxígeno/metabolismo , Compuestos de Sulfhidrilo/metabolismo
8.
Sci Rep ; 9(1): 14516, 2019 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-31601912

RESUMEN

Non Hodgkin lymphoma, predominantly Diffuse Large B-cell Lymphoma (DLBCL) has been reported to have a significant association with Hepatitis B virus (HBV). We investigated the presence of different gene segments of HBV in plasma, B-cells and tumor tissues from DLBCL patients and explored the genetic variability of HBV within and across different compartments in a host using Next Generation Sequencing. Despite all 40 patients being HBV seronegative, 68% showed evidence of occult HBV. Sequencing of these gene segments revealed inter-compartment viral variants in 26% of them, each with at least one non-synonymous mutation. Between compartments, core gene variants revealed Arg94Leu, Glu86Arg and Ser41Thr while X gene variants revealed Phe73Val, Ala44Val, Ser146Ala and Ser147Pro. In tumor compartments per se, several mis-sense mutations were detected, notably the classic T1762A/A1764G mutation in the basal core promoter. In addition, a virus surface antigen mis-sense mutation resulting in M125T was detected in all the samples and could account for surface antigen negativity and occult HBV status. It would be interesting to further explore if a temporal accumulation of viral variants within a favored niche, like patients' lymphocytes, could bestow survival advantage to the virus, and if certain pro-oncogenic HBV variants could drive lymphomagenesis in DLBCL.


Asunto(s)
Virus de la Hepatitis B/clasificación , Hepatitis B/virología , Linfoma de Células B Grandes Difuso/virología , Cuasiespecies , Adulto , Anciano , Anciano de 80 o más Años , ADN Viral/genética , Variación Genética , Hepatitis B/complicaciones , Antígenos de Superficie de la Hepatitis B/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Mutación Missense , Estudios Prospectivos , Adulto Joven
9.
Chem Biol Interact ; 174(2): 88-97, 2008 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-18561905

RESUMEN

The present study has been designed to investigate the protective role of taurine (2-aminoethanesulfonic acid), a sulfur containing conditionally essential amino acid, against cadmium-induced cardiac dysfunction in mice. Cadmium chloride (CdCl(2)) was used as the source of cadmium and it was administered orally at a dose of 4mg/kg body weight for 6 days. Cadmium exposure caused significant accumulation of the cadmium and iron in mice hearts tissue. Levels of serum specific markers related to cardiac impairments, e.g. total cholesterol, HDL cholesterol and triglyceride were altered due to cadmium toxicity. Reduction in the activities of antioxidant enzymes, namely, superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx) and glucose-6-phosphate dehydrogenase (G6PD) have been observed in cadmium exposed mice. Cadmium intoxication also decreased the cardiac glutathione (GSH) and total thiols contents and increased the levels of oxidized glutathione (GSSG), lipid peroxidation end products, protein carbonyl content and the extent of DNA fragmentation. Oral administration of taurine at a dose of 100mg/kg body weight for 5 days, however, prevented all the toxin-induced oxidative impairments mentioned above. "Ferric Reducing/Antioxidant Power (FRAP) assay" showed that taurine could protect the cardiac tissue by preventing cadmium-induced reduction of the intracellular antioxidant power. Histological examination of cardiac segments also supported the beneficial role of taurine against cadmium-induced damages in the murine hearts. Effect of a well established antioxidant, vitamin C has been included in the study as a positive control. Combining all, results suggest that taurine attenuates cadmium-induced impairment in mice hearts.


Asunto(s)
Cloruro de Cadmio/toxicidad , Contaminantes Ambientales/toxicidad , Cardiopatías/prevención & control , Corazón/efectos de los fármacos , Estrés Oxidativo , Taurina/administración & dosificación , Administración Oral , Animales , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Quimioprevención , Fragmentación del ADN/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Enzimas/metabolismo , Cardiopatías/metabolismo , Cardiopatías/patología , Masculino , Ratones , Miocardio/metabolismo
10.
J Biochem Mol Toxicol ; 22(1): 15-26, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18273903

RESUMEN

Arsenic, a notoriously poisonous metalloid, is ubiquitous in the environment, and it affects nearly all organ systems of animals including humans. The present study was designed to investigate the preventive role of a triterpenoid saponin, arjunolic acid against arsenic-induced oxidative damage in murine brain. Sodium arsenite was selected as a source of arsenic for this study. The free-radical-scavenging activity and the in vivo antioxidant power of arjunolic acid were determined from its 2,2-diphenyl-1-picryl hydrazyl radical scavenging ability and ferric reducing/antioxidant power assay, respectively. Oral administration of sodium arsenite at a dose of 10 mg/kg body weight for 2 days significantly decreased the activities of antioxidant enzymes, superoxide dismutase, catalase, glutathione-S-transferase, glutathione reductase and glutathione peroxidase, the level of cellular metabolites, reduced glutathione, total thiols and increased the level of oxidized glutathione. In addition, it enhanced the levels of lipid peroxidation end products and protein carbonyl content. Treatment with arjunolic acid at a dose of 20 mg/kg body weight for 4 days prior to arsenic administration almost normalized above indices. Histological findings due to arsenic intoxication and arjunolic acid treatment supported the other biochemical changes in murine brains. Results of 2,2-diphenyl-1-picryl hydrazyl radical scavenging and ferric reducing/antioxidant power assays clearly showed the in vitro radical scavenging as well as the in vivo antioxidant power of arjunolic acid, respectively. The effect of a well-established antioxidant, vitamin C, has been included in the study as a positive control. Combining all, results suggest that arjunolic acid possessed the ability to ameliorate arsenic-induced oxidative insult in murine brain and is probably due to its antioxidant activity.


Asunto(s)
Arsénico/toxicidad , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/farmacología , Triterpenos/farmacología , Animales , Antioxidantes/metabolismo , Compuestos de Bifenilo/farmacología , Encéfalo/patología , Sistema Libre de Células , Relación Dosis-Respuesta a Droga , Enzimas/metabolismo , Depuradores de Radicales Libres/farmacología , Hidrazinas/farmacología , Hierro/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Ratones , Oxidación-Reducción/efectos de los fármacos , Picratos , Sustancias Protectoras/química , Carbonilación Proteica/efectos de los fármacos , Triterpenos/química
11.
Reprod Toxicol ; 26(3-4): 282-91, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18926901

RESUMEN

The aim of the present study was to investigate the role of taurine against cadmium induced testicular pathophysiology. Cadmium (in the form of Cadmium chloride, CdCl(2)) administration at a dose of 4 mg/kg body weight for 6 days significantly decreased testicular Delta(5)-3beta-HSD and 17beta-HSD activities along with the reduction in the plasma testosterone level. In addition, reductions in testicular sperm count as well as loss in sperm motility were also observed in Cd-intoxication. Cd increased the intracellular concentration of reactive oxygen species and testicular Cd accumulation. Besides, increased levels of lipid peroxidation, protein carbonylation, glutathione disulfide and DNA fragmentation as well as decreased levels of the activities of the antioxidant enzymes, total thiols and reduced glutathione were also found to be associated with this toxicity. Taurine pretreatment at a dose of 100 mg/kg body weight for 5 days, on the other hand, could prevent all the Cd-induced testicular pathophysiology and oxidative insult related studied parameters. Taurine treatment, in addition also increased the in vivo ferric reducing antioxidant power linearly up to a dose of 100 mg/kg body weight. Histological examination of testicular sections from experimental animals supported these results. The effect of a well established antioxidant, vitamin C has been included in the study as a positive control. Combining all, data suggest that being an antioxidant, taurine plays a beneficial role against Cd-induced adverse effects on the male reproductive system.


Asunto(s)
Cloruro de Cadmio/toxicidad , Taurina/farmacología , Testículo/efectos de los fármacos , Animales , Cloruro de Cadmio/farmacocinética , Fragmentación del ADN/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratones , Especies Reactivas de Oxígeno/metabolismo , Recuento de Espermatozoides , Motilidad Espermática/efectos de los fármacos , Testículo/metabolismo , Testículo/patología
12.
Pathophysiology ; 15(3): 147-56, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18434106

RESUMEN

Arsenic is highly toxic naturally occurring element that affects numerous organ systems in humans. Present study was designed to investigate the preventive role of a triterpenoid saponin, arjunolic acid (AA) against arsenic-induced nephrotoxicity in mouse model. For this study, NaAsO(2) was chosen as the source of arsenic. Oral administration of NaAsO(2) at a dose of 10mg/kg body weight for 2 days caused significant accumulation of arsenic in renal tissues as well as altered the activities of serum markers, urea nitrogen (UN) and creatinine, antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), glutathione reductase (GR) and glutathione peroxidase (GPx), level of cellular metabolites, reduced glutathione (GSH), oxidized glutathione (GSSG) and total thiols, level of lipid peroxidation end products and protein carbonyl content. Treatment with AA at a dose of 20mg/kg body weight for 4 days almost normalized above indices. Histological studies also indicated preventive role of AA against NaAsO(2)-induced nephrotoxicity. The radical scavenging activity and in vivo antioxidant power of AA were determined from its DPPH radical scavenging ability and ferric reducing/antioxidant power (FRAP), respectively. A well-known antioxidant, vitamin C was used as positive control throughout the study. Combining all, results suggest that arsenic could cause kidney damage by inducing oxidative stress in mice and that could be prevented by AA.

13.
J Biochem Mol Biol ; 40(3): 382-95, 2007 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-17562290

RESUMEN

The herb, Cajanus indicus L, is well known for its hepatoprotective action. A 43 kD protein has been isolated, purified and partially sequenced from the leaves of this herb. A number of in vivo and in vitro studies carried out in our laboratory suggest that this protein might be a major component responsible for the hepatoprotective action of the herb. Our successive studies have been designed to evaluate the potential efficacy of this protein in protecting the hepatic as well as renal tissues from the sodium fluoride (NaF) induced oxidative stress. The experimental groups of mice were exposed to NaF at a dose of 600 ppm through drinking water for one week. This exposure significantly altered the activities of the antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), glutathione reductase (GR) and the cellular metabolites such as reduced glutathione (GSH), oxidized glutathione (GSSG), total thiols, lipid peroxidation end products in liver and kidney compared to the normal mice. Intraperitoneal administration of the protein at a dose of 2 mg/kg body weight for seven days followed by NaF treatment (600 ppm for next seven days) normalized the activities of the hepato-renal antioxidant enzymes, the level of cellular metabolites and lipid peroxidation end products. Post treatment with the protein for four days showed that it could help recovering the damages after NaF administration. Time-course study suggests that the protein could stimulate the recovery of both the organs faster than natural process. Effects of a known antioxidant, vitamin E, and a non-relevant protein, bovine serum albumin (BSA) have been included in the study to validate the experimental data. Combining all, result suggests that NaF could induce severe oxidative stress both in the liver and kidney tissues in mice and the protein possessed the ability to attenuate that hepato-renal toxic effect of NaF probably via its antioxidant activity.


Asunto(s)
Cajanus/química , Enfermedades Renales/prevención & control , Hepatopatías/prevención & control , Proteínas de Plantas/farmacología , Animales , Catalasa/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas , Activación Enzimática/efectos de los fármacos , Glutatión/metabolismo , Glutatión Reductasa/metabolismo , Enfermedades Renales/inducido químicamente , Enfermedades Renales/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hepatopatías/metabolismo , Masculino , Ratones , Peso Molecular , Proteínas de Plantas/química , Fluoruro de Sodio/toxicidad , Superóxido Dismutasa/metabolismo , Factores de Tiempo
14.
Chem Biol Interact ; 170(3): 187-200, 2007 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-17854788

RESUMEN

Arsenic is a well-established environmental toxin, which damages various organs of the body. A triterpenoid saponin, arjunolic acid (AA) has been isolated from the bark of Terminalia arjuna. The present study was conducted to investigate the preventive role of AA against arsenic-induced cytotoxicity in isolated murine hepatocytes. Sodium arsenite (NaAsO(2)) was chosen as the source of arsenic. Incubation of the hepatocytes with NaAsO(2) (1 mM) for 2 h caused reduction in the cell viability and activities of the intracellular enzymatic as well as non-enzymatic antioxidants. Treatment of NaAsO(2) enhanced lipid peroxidation and also increased the activities of the membrane leakage enzymes. Administration of AA (100 microg/ml) before and with the toxin almost normalized the altered activities of antioxidant indices. AA possesses free radical scavenging activity and could enhance the cellular anti-oxidant capability against NaAsO(2)-induced cyto-toxicity. The cytoprotective activity of AA was found to be comparable to that of a known antioxidant, vitamin C. Experimental results, therefore, suggest that AA protects arsenic-induced cytotoxicity in murine hepatocytes.


Asunto(s)
Arsénico/toxicidad , Hepatocitos/efectos de los fármacos , Saponinas/toxicidad , Triterpenos/toxicidad , Animales , Antioxidantes/metabolismo , Arsénico/química , Biomarcadores , Compuestos de Bifenilo/toxicidad , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Compuestos Férricos/farmacología , Radicales Libres/química , Hepatocitos/metabolismo , Hidrazinas/toxicidad , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratones , Estructura Molecular , Picratos , Terminalia/química , Triterpenos/química
15.
Toxicol In Vitro ; 21(8): 1419-28, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17624716

RESUMEN

Arsenic is a potent environmental toxin. Present study has been designed to evaluate the protective role of taurine (2-aminoethanesulfonic acid) against arsenic induced cytotoxicity in murine hepatocytes. Sodium arsenite (NaAsO(2)) was chosen as the source of arsenic. Incubation of hepatocytes with the toxin (1 mM) for 2 h reduced the cell viability as well as intra-cellular antioxidant power. Increased activities of alanine transaminase (ALT) and alkaline phosphatase (ALP) due to toxin exposure confirmed membrane damage. Toxin treatment caused reduction in the activities of the antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), glutathione reductase (GR) and glutathione peroxidase (GPx). In addition, the same treatment reduced the level of glutathione (GSH), elevated the level of oxidized glutathione (GSSG) and increased the extent of lipid peroxidation. Incubation of hepatocytes with taurine, both prior to and in combination with NaAsO(2), attenuated the extent of lipid peroxidation and enhanced the activities of enzymatic as well as non enzymatic antioxidants. Besides, taurine administration normalized the arsenic-induced enhanced levels of the marker enzymes ALT and ALP in hepatocytes. The cytoprotective activity of taurine against arsenic poisoning was found to be comparable to that of a known antioxidant, vitamin C. Combining all, the results suggest that taurine protects mouse hepatocytes against arsenic induced cytotoxicity.


Asunto(s)
Arsénico/toxicidad , Citotoxinas/toxicidad , Hepatocitos/efectos de los fármacos , Taurina/farmacología , Alanina Transaminasa , Fosfatasa Alcalina , Aminoácidos Esenciales/farmacología , Animales , Antioxidantes , Arsénico/antagonistas & inhibidores , Biomarcadores , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Citotoxinas/antagonistas & inhibidores , Glutatión , Disulfuro de Glutatión , Hepatocitos/enzimología , Peroxidación de Lípido , Masculino , Ratones
16.
Indian J Med Res ; 126(1): 63-7, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17890826

RESUMEN

BACKGROUND & OBJECTIVES: Members of the genus Acinetobacter are an important cause of nosocomial infections and with widespread resistance to various antibiotics. Extended spectrum beta lactamase (ESBL) associated resistance among Acinetobacter species is now known. The aim of this study was to speciate clinical isolates of Acinetobacter, analyze their resistance patterns, identify the production ESBLs and compare the role of different cephalosporins in detecting ESBL production in the isolates. METHODS: One hundred and fifty clinical isolates of Acinetobacter were speciated by various phenotypic tests. Antibiotic susceptibility was determined by the standard disc diffusion method. ESBL production was detected by the double disk approximation test using clavulanate containing disk and four different cephalosporin disks. Results of the above test were confirmed using the NCCLS phenotypic confirmatory test for ESBLs on a limited number of isolates. RESULTS: Most of the isolates were of respiratory origin. A. calcoaceticus A. baumannii (Acb) complex was the predominant species isolated (75%). Most isolates were resistant to the antibiotics tested including the third generation cephalosporins. Most isolates were sensitive to carbapenems and cefoperazone-sulbactam. ESBL production was detected in 28 per cent of the isolates. In the double disc approximation test, cefepime and cefotaxime could detect most of the ESBLs in Acinetobacter isolates. INTERPRETATION & CONCLUSION: A high level of antibiotic resistance was found in Acinetobacter in our study. Acb complex was the predominant and the more resistant species. Relatively high levels (28%) of ESBL have been detected in Acinetobacter and may reflect the scenario in India. ESBL production in Acinetobacter should be promptly detected and reported as it helps in treating individual cases and also in controlling the spread of these resistant phenotypes to other individuals.


Asunto(s)
Acinetobacter/efectos de los fármacos , Acinetobacter/enzimología , Farmacorresistencia Bacteriana , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/biosíntesis
17.
Basic Clin Pharmacol Toxicol ; 101(5): 333-8, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17910617

RESUMEN

Arsenic is one of the ubiquitous environmental pollutants, which affects nearly all organ systems. The present study has been carried out to investigate the hepatoprotective role of arjunolic acid, a triterpenoid saponin, against arsenic-induced oxidative damages in murine livers. Administration of sodium arsenite at a dose of 10 mg/kg body weight for 2 days significantly reduced the activities of antioxidant enzymes, superoxide dismutase, catalase, glutathione S-transferase, glutathione reductase and glutathione peroxidase as well as depleted the level of reduced glutathione and total thiols. In addition, sodium arsenite also increased the activities of serum marker enzymes, alanine transaminase and alkaline phosphatase, enhanced DNA fragmentation, protein carbonyl content, lipid peroxidation end-products and the level of oxidized glutathione. Studies with arjunolic acid show that in vitro it possesses free radical-scavenging and in vivo antioxidant activities. Treatment with arjunolic acid at a dose of 20 mg/kg body weight for 4 days prior to arsenic administration prevents the alterations of the activities of all antioxidant indices and levels of the other parameters studied. Histological studies revealed less centrilobular necrosis in the liver treated with arjunolic acid prior to arsenic intoxication compared to the liver treated with the toxin alone. Effects of a known antioxidant, vitamin C, have been included in the study as a positive control. In conclusion, the results suggest that arjunolic acid possesses the ability to attenuate arsenic-induced oxidative stress in murine liver probably via its antioxidant activity.


Asunto(s)
Intoxicación por Arsénico/prevención & control , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Triterpenos/uso terapéutico , Animales , Antioxidantes/farmacología , Ácido Ascórbico/metabolismo , Compuestos de Bifenilo , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Fragmentación del ADN/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Glutatión/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hígado/patología , Hígado/ultraestructura , Pruebas de Función Hepática , Masculino , Ratones , Picratos/química , Terminalia/química , Triterpenos/aislamiento & purificación
18.
Pathophysiology ; 14(2): 71-8, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17611085

RESUMEN

Chronic and acute overproduction of reactive oxygen species (ROS) plays a positive role in the development of cardiovascular diseases under pathophysiological conditions. However, very little is known about carbon tetrachloride (CCl(4)) induced cardiac oxidative stress. The present study was conducted to find out CCl(4) induced oxidative insult in cardiac tissue and the cardioprotective effect of the 70% ethanol extractable active constituents of the bark of Terminalia arjuna (TA) against that stress in mice. Oral administration of CCl(4) at a dose of 1ml/kg body weight for 2 days significantly reduced the activities of antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST), as well as depleted the level of reduced glutathione (GSH) in the cardiac tissue. In addition, extent of lipid peroxidation and the level of oxidized glutathione (GSSG) were increased under the same experimental conditions. Oral treatment of the active constituents of TA at a dose of 50mg/kg body weight for 7 days prior to CCl(4) administration significantly restored the activities of all antioxidant enzymes as well as increased the level of GSH and decreased the level of lipid peroxidation end products. In addition, FRAP assay showed that the active constituents of TA enhanced the cardiac intracellular antioxidant activity. Histological studies also supported the cardioprotective role of the active constituents. The active constituents-induced protective effect was compared with a known antioxidant, vitamin C. To the best of our knowledge, this is the first report describing the CCl(4) induced cardiac oxidative stress and cardioprotective action of the active phytoconstituents of Terminalia arjuna against that oxidative insult.

19.
Pathophysiology ; 14(1): 47-54, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17403599

RESUMEN

Present study has been carried out to evaluate the protective and curative roles of a 43kD protein isolated from the herb Cajanus indicus L. on sodium fluoride (NaF) induced toxicity in mice erythrocytes. In the preventive study, mice were divided into five groups consisting of six in each for the experiments. Group I animals got water and used as normal controls, animals of groups II and IV were exposed to 600ppm fluoride in water for 7 days. Animals of group III were treated with the protein (2mg/kg body weight) intraperitoneally for 7 days followed by NaF treatment for next 7 days (600ppm). Animals of group V were treated with NaF (600ppm) followed by the protein treatment (2mg/kg body weight) for the same time as mentioned for group III. In the curative study, four groups of six mice were compared. Erythrocytes were isolated, and the antioxidant enzyme superoxide dismutase (SOD) as well as the levels of reduced and oxidized glutathione (GSH and GSSG), total thiols and lipid peroxidation end products were measured in those cells. There was a significant increase in lipid peroxidation along with a decrease in total thiols and SOD activity in the erythrocytes of NaF only and NaF bovine serum albumin treated animals. The 43kD protein treatment in animals either prior or post to fluoride administration normalized the levels of parameters measured and restored the SOD activity in mice erythrocytes. Data suggest that the 43kD protein possesses significant protective and curative activity against NaF induced oxidative stress in erythrocytes.

20.
BMC Complement Altern Med ; 7: 11, 2007 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-17456244

RESUMEN

BACKGROUND: Galactosamine (GalN), an established experimental toxin, mainly causes liver injury via the generation of free radicals and depletion of UTP nucleotides. Renal failure is often associated with end stage liver damage. GalN intoxication also induces renal dysfunction in connection with hepatic disorders. Present study was designed to find out the effect of a protein isolated from the leaves of the herb Cajanus indicus against GalN induced renal damage. METHODS: Both preventive as well as curative effect of the protein was investigated in the study. GalN was administered intraperitoneally at a dose of 800 mg/kg body weight for 3 days pre and post to protein treatment at an intraperitoneal dose of 2 mg/kg body weight for 4 days. The activities of antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and glutathione-S-transferase (GST), levels of cellular metabolites, reduced glutathione (GSH), total thiols, oxidized glutathione (GSSG) and lipid peroxidation end products were determined to estimate the status of the antioxidative defense system. In addition, serum creatinine and urea nitrogen (UN) levels were also measured as a marker of nephrotoxicity. RESULTS: Results showed that GalN treatment significantly increased the serum creatinine and UN levels compared to the normal group of mice. The extent of lipid peroxidation and the level of GSSG were also enhanced by the GalN intoxication whereas the activities of antioxidant enzymes SOD, CAT, GR and GST as well as the levels of total thiols and GSH were decreased in the kidney tissue homogenates. Protein treatment both prior and post to the toxin administration successfully altered the effects in the experimental mice. CONCLUSION: Our study revealed that GalN caused a severe oxidative insult in the kidney. Protein treatment both pre and post to the GalN intoxication could protect the kidney tissue against GalN induced oxidative stress. As GalN induced severe hepatotoxicity followed by renal failure, the protective role of the protein against GalN induced renal damages is likely to be an indirect effect. Since the protein possess hepatoprotective activity, it may first ameliorate GalN-induced liver damage and consequently the renal disorders are reduced. To the best of our knowledge, this is probably the first report describing GalN-induced oxidative stress in renal damages and the protective role of a plant protein molecule against it.


Asunto(s)
Cajanus , Galactosamina/toxicidad , Enfermedades Renales/inducido químicamente , Enfermedades Renales/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Fitoterapia/métodos , Extractos Vegetales/uso terapéutico , Animales , Biomarcadores/sangre , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Modelos Animales de Enfermedad , Glutatión , Glutatión Reductasa , Glutatión Transferasa , Enfermedades Renales/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratones , Hojas de la Planta , Compuestos de Sulfhidrilo/metabolismo , Superóxido Dismutasa/metabolismo , Resultado del Tratamiento
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