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1.
Cureus ; 15(3): e36473, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37090321

RESUMEN

Introduction Myofascial pain is defined as pain arising primarily in muscles and associated with multiple trigger points. Among the non-pharmacological methods, trigger point injection and electrotherapy are effective methods to treat myofascial pain syndrome. This study compares the effectiveness of dry needling (DN) and transcutaneous electrical nerve stimulation (TENS) in reducing cervical pain intensity and improving cervical range of motion in patients with neck pain due to myofascial trigger points. Methods Fifty patients were enrolled and randomized into two groups. Patients in group A received dry needling, and those in group B received TENS. Patients were evaluated using the Visual Analog Scale (VAS), Neck Disability Index (NDI), and Cervical Range of Motion (CROM) before the treatment and on days 14 and 28 after the treatment. The unpaired t-test was used to evaluate quantitative data, except for VAS, where the Mann-Whitney U test was used. All quantitative variables had a normal distribution with a standard deviation except for pain intensity (VAS), which deviated from the normal distribution. The significance level was set at a P-value=0.05. Results Both DN and TENS groups showed significant improvement in VAS, NDI, and CROM between days 0 and 28 (p=<0.001). The DN group showed greater improvements in pain intensity from day 0 to day 28 (p =<0.001). Between days 0 and 28, there was no discernible difference in NDI changes between the groups (p = 0.157 and p = 0.799, respectively). Mixed results were obtained for CROM, with significant improvement of cervical flexion in the dry needling group (p=<0.008) and significant improvement of cervical rotation to the painful side in the TENS group (<0.001). Conclusion Both dry needling and TENS are effective in reducing pain and improving NDI and CROM in patients with neck pain due to myofascial trigger points. However, as dry needling is more effective in pain reduction, a single session of dry needling is more beneficial and cost-effective as compared to multiple sessions of TENS.

2.
Toxicol In Vitro ; 85: 105478, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36122807

RESUMEN

A major global problem is chronic exposure to inorganic arsenic (iAs) which causes various health hazards including cancer. Escalation of reactive oxygen species (ROS) generation by chronic iAs exposure promotes Epithelial to Mesenchymal transition (EMT) which is followed by metastatic progression. In the present study, skin keratinocyte cells (HaCaT) were divided into three groups: (i) untreated, (ii) chronically iAs exposed, (iii) black tea extract (BTE) along with iAs treated. ROS was estimated by flowcytometry, expression of EMT markers were assessed by flowcytometry, western-blotting and Immunofluorescence. For metastatic studies, wound-healing assay, gelatin zymography, western-blot, transwell migration/invasion assay had been performed. Long term exposure of HaCaT cells to iAs causes excess generation of ROS. Morphological transformation and EMT were apparent at 210 days of exposure. Development of metastatic characteristics were observed at 240 days. Alterations in the parameters induced by iAs were found to be ameliorated by BTE. BTE was found to quench excess generation of ROS by iAs, subsequently inhibiting the chain of events like EMT and metastasis. Therefore, BTE may be considered as a potential phytochemical to prevent the deleterious effect of iAs. Skin carcinogenesis induced by iAs may thus be prevented by BTE via inhibition of EMT.


Asunto(s)
Arsénico , Neoplasias , Humanos , Transición Epitelial-Mesenquimal , Arsénico/toxicidad , Especies Reactivas de Oxígeno/farmacología , Gelatina/farmacología , Queratinocitos , Proliferación Celular ,
3.
Asian Pac J Cancer Prev ; 22(11): 3647-3661, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34837924

RESUMEN

OBJECTIVE: Chronic exposure to inorganic arsenic (iAs) may cause a number of health problems including skin cancer. Present study is aimed to look into the potential of black tea extract (BTE) to prevent the development of skin carcinoma in Swiss albino mice. METHODS: The study was done on Swiss albino mice, chronically exposed to inorganic arsenic. 150 mice were housed in different cages, 5 in each cage. The control mice did not receive any treatment. Mice were sacrificed at 30, 90, 180, 270 and 330 days. Development of carcinogenesis was assessed by histological studies. Generation of Reactive Oxygen Species (ROS) and Reactive Oxygen Species (RNS) were estimated using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) and Greiss reagent respectively, and their consequences on DNA (by Micronuclei and Comet assay), protein (by protein carbonyl assay kit) and lipid (by lipid peroxidation) were estimated. Activity of antioxidant enzymes, along with total antioxidant capacity were measured by respective kits. Repair percentage was obtained by Comet assay. Western blotting was employed to study the expression of repair enzymes and expression of cytokines. Sandwich Enzyme-linked Immunosorbent Assay (ELISA) technique was employed to study the activity of various cytokines. RESULTS: At 330 days, invasive squamous cell carcinoma of the skin developed. With increasing time generation of ROS and RNS increased, causing damage to DNA, protein and lipid. Antioxidant defence system gets repressed with time. Capacity to repair the DNA damage is inhibited by iAs, due to alteration in repair enzymes - XRCC I, DNA Ligase I, PARP I, ERCC1, ERCC2, XPA, DNA Ligase IV, DNA PKc and Ku-70. Another consequence of iAs exposure is chronic inflammation due to disrupted cytokine level. Intervention with BTE reverses these deleterious effects, preventing development of skin carcinogenesis.


Asunto(s)
Intoxicación por Arsénico/tratamiento farmacológico , Arsenicales , Carcinoma de Células Escamosas/prevención & control , Extractos Vegetales/farmacología , Neoplasias Cutáneas/prevención & control , , Animales , Antioxidantes/farmacología , Intoxicación por Arsénico/complicaciones , Carcinoma de Células Escamosas/inducido químicamente , Daño del ADN/efectos de los fármacos , Modelos Animales de Enfermedad , Ratones , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Cutáneas/inducido químicamente
4.
Front Pharmacol ; 12: 584019, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33790782

RESUMEN

Suaeda monoica Forssk. ex J.F.Gmel. (Amaranthaceae), a mangrove associate and ethno-medicinal herb of Indian Sundarbans, was investigated as a promising source of bioactive compounds. Various polar and nonpolar solvent extracts of the leaf and root-shoot parts of the plant exhibited antioxidant, antibacterial, antifungal, allelopathic, mosquitocidal, antihaemolytic and antidiuretic potential. Moreover, to meet pharmacological requirements, the antioxidant ability of the plant was validated by both chemical and biological analyses. Extraction yield and presence of different phytochemicals like phenolics, flavonoids, tannins and saponins were compared in various solvent-extracted fractions. Principle component analysis revealed that the antioxidant property present in different extracts maintained a positive correlation with the occurrence of polyphenols (phenolics, tannins and flavonoids). Biochemical evaluation, HPLC examination and GC-MS analysis showed a differential level of the presence of various phytochemicals in different solvent extracts. In contrast to mosquitocidal, antioxidant, antihaemolytic and phytotoxic properties which were observed to be dominant in polar solvent extracts, maximum antibacterial potency was detected in nonpolar n-hexane fractions. Overall, the plant extract is nontoxic in nature and a dose amounting to 3,000 mg/kg was well tolerated by Swiss albino mice. A combination of HPLC and GC-MS analyses showed the presence of a large number of structurally diverse phytochemicals, many of which had already been reported as insecticidal, mosquitocidal, antibacterial, herbicidal, antidiuretic, antioxidant and anti-haemolytic compounds. All these findings support that the least explored traditional edible medicinal mangrove associate S.monoica is enriched with multiple bioactive molecules and may be considered as one of the richest sources of various lead molecules of pharmaceutical importance.

5.
Anticancer Agents Med Chem ; 15(1): 57-65, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25052988

RESUMEN

Cancer is a serious global health issue. Cancer of the cervix is one of the leading gynecological malignancies worldwide; though it is more prevalent in the developing countries. Fruitful approaches are needed to control cervical cancer. Awareness through proper education, screening and early detection may pave a way to combat the disease process in the first place. Surgery, chemotherapy and radiotherapy are some of the common modes of treatment for cervical cancer. Conventional medical treatments often are not able to eliminate the offending growth fully and are not free from complications. Side effects very often are disastrous. Therefore, it is high time to focus our attention to bring about a novel way to tackle the problem. Advocating holistic approach using plant derived phytochemicals may address this health problem. These molecules show potent anticancer potential and are free from toxicity. Adjunctive therapies using phytochemicals may prove to be of tremendous importance. Plants are a prime source of effective drugs for the treatment of various forms of cancer. Many of these compounds are well characterized and have led the researchers to develop potential chemotherapeutic agents. Neutraceuticals may not replace the conventional treatment regimen, but they may enhance the efficacy of chemotherapy and radiotherapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Fitoquímicos/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Femenino , Humanos , Plantas/química
6.
J Environ Pathol Toxicol Oncol ; 30(4): 311-22, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22181980

RESUMEN

Arsenic (As) contamination in groundwater is of increasing health concern in West Bengal, India. Arsenic has been associated with various human cancers, but the precise mechanism of its co-carcinogenic action is not clearly elucidated. Oxidative stress and defective repair mechanisms may promote accumulation of mutations and may be a stepping stone for carcinogenesis. Prevention of arsenic-induced oxidative stress and repair inhibition may reduce the chances of initiation of cancer. Tea polyphenols are reported to have excellent chemopreventive properties against cancer. This study aimed to elucidate the role of tea against arsenic-induced formation of 8-hydroxy-2'-deoxyguanosine (8OHdG) and arsenic-suppressed DNA repair in Swiss albino mice. Both green and black tea gave fruitful results in the reduction of 8OHdG and 8-oxoguanine DNA glycosylase (OGG1) in Swiss albino mice administered sodium arsenite (As III). DNA repair enzymes--such as PARP1, DNA ß-polymerase, XRCC1, DNA ligase III, DNA protein kinase (catalytic subunit), XRCC 4, DNA ligase IV, and DNA topoisomerase IIß--were induced by the phytochemicals at both the protein and genetic levels. Thus, tea polyphenols may prove effective in treating arsenic-induced carcinogenesis.


Asunto(s)
Antioxidantes/farmacología , Arsenitos/farmacología , Daño del ADN , Reparación del ADN/efectos de los fármacos , Polifenoles/farmacología , Compuestos de Sodio/farmacología , Té/química , 8-Hidroxi-2'-Desoxicoguanosina , Animales , Arsenitos/sangre , Ensayo Cometa , Aductos de ADN/efectos de los fármacos , ADN Glicosilasas/genética , ADN Glicosilasas/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/biosíntesis , Ratones , ARN Mensajero/metabolismo , Compuestos de Sodio/sangre
7.
Eur J Cancer Prev ; 20(2): 123-31, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21332098

RESUMEN

Induction of oxidative stress and inhibition of DNA repair are possible modes of arsenic-induced carcinogenesis. In West Bengal, India, several districts contain high levels of arsenic, which are far above the WHO-recommended standard. Prevention of arsenic-induced oxidative stress and induction of repair enzymes by curcumin, an active ingredient of turmeric, may be an effective strategy to combat the adverse effects of arsenic. This study aimed at observing the role of curcumin in reducing 8-hydroxy-20-deoxyguanosine formation and enhancing DNA repair capacity in the arsenic-exposed population of West Bengal. Chronically arsenic-exposed volunteers (n= 66), who were asymptomatic, were selected for this study. Our results indicated that curcumin suppressed the 8-hydroxy-20-deoxyguanosine level and OGG1 expression, which were increased by arsenic. Curcumin also induced DNA repair enzymes involved in both base excision repair and nonhomologous end-joining pathways. In this study, both the protein expression and genetic profile were observed for poly-ADP-ribose polymerase 1, DNA b polymerase, X ray repair cross complement 1, DNA ligase III, DNA protein kinase catalytic sub-unit, X ray repair cross-complement 4, DNA ligase IV, and topoisomerase II b. The results indicated that arsenic-inhibited DNA repair was induced by curcumin, both at protein and genetic levels. Thus, curcumin intervention may be a useful modality for the prevention of arsenic-induced carcinogenesis.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Intoxicación por Arsénico/tratamiento farmacológico , Curcumina/uso terapéutico , Daño del ADN/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , 8-Hidroxi-2'-Desoxicoguanosina , Adulto , Intoxicación por Arsénico/sangre , Western Blotting , Ensayo Cometa , ADN Ligasa (ATP) , ADN Ligasas/metabolismo , ADN-Topoisomerasas de Tipo II/metabolismo , Proteínas de Unión al ADN/metabolismo , ADN Polimerasa Dirigida por ADN/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas de Xenopus
8.
Asian Pac J Cancer Prev ; 11(1): 239-47, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20593964

RESUMEN

Inorganic arsenic (As) is considered as a human carcinogen because it is associated with cancers of skin, lung, liver and bladder in exposed population. Consumption of As contaminated ground water for long term causes oxidative stress. Generation of reactive oxygen species (ROS), beyond the body's endogenous antioxidant balance results severe imbalance of the cellular antioxidant defense mechanism. The present study was conducted to investigate the antioxidative effect of curcumin against sodium arsenite (As III) induced oxidative damage in Swiss albino mice. Bio-monitoring with comet assay and micronucleus assay revealed that the increase in genotoxicity caused by As III was counteracted when mice were orally administered with 5, 10 and 15 mg curcumin kg-1 bw (body weight) daily. ROS generation, lipid peroxidation and protein carbonyl content, which were elevated by As III, were reduced when treated with curcumin. Curcumin also exhibited protective action against the As III induced depletion of antioxidants like catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST) and glutathione (GSH) in mice liver tissue. Thus the present work provides a direct evidence for the involvement of curcumin in reducing As III induced oxidative stress in Swiss albino mice by virtue of its antioxidant potential and trapping of free radicals.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Arseniatos/toxicidad , Intoxicación por Arsénico/prevención & control , Curcumina/uso terapéutico , Daño del ADN/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Animales , Antioxidantes/metabolismo , Intoxicación por Arsénico/metabolismo , Ensayo Cometa , Modelos Animales de Enfermedad , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratones , Carbonilación Proteica/efectos de los fármacos
9.
Hum Exp Toxicol ; 29(6): 513-24, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20056736

RESUMEN

Groundwater arsenic contamination has been a health hazard for West Bengal, India. Oxidative stress to DNA is recognized as an underlying mechanism of arsenic carcinogenicity. A phytochemical, curcumin, from turmeric appears to be potent antioxidant and antimutagenic agent. DNA damage prevention with curcumin could be an effective strategy to combat arsenic toxicity. This field trial in Chakdah block of West Bengal evaluated the role of curcumin against the genotoxic effects of arsenic. DNA damage in human lymphocytes was assessed by comet assay and fluorescence-activated DNA unwinding assay. Curcumin was analyzed in blood by high performance liquid chromatography (HPLC). Arsenic induced oxidative stress and elucidation of the antagonistic role of curcumin was done by observation on reactive oxygen species (ROS) generation, lipid peroxidation and protein carbonyl. Antioxidant enzymes like catalase, superoxide dismutase, glutathione reductase, glutathioneS-transferase, glutathione peroxidase and non-enzymatic glutathione were also analyzed. The blood samples of the endemic regions showed severe DNA damage with increased levels of ROS and lipid peroxidation. The antioxidants were found with depleted activity. Three months curcumin intervention reduced the DNA damage, retarded ROS generation and lipid peroxidation and raised the level of antioxidant activity. Thus curcumin may have some protective role against the DNA damage caused by arsenic.


Asunto(s)
Antimutagênicos/uso terapéutico , Antioxidantes/uso terapéutico , Intoxicación por Arsénico/tratamiento farmacológico , Curcumina/uso terapéutico , Daño del ADN/efectos de los fármacos , Adulto , Antimutagênicos/análisis , Antioxidantes/análisis , Antioxidantes/farmacología , Arsénico/análisis , Arsénico/sangre , Arsénico/toxicidad , Curcumina/análisis , Curcumina/farmacología , ADN , Femenino , Glutatión/sangre , Glutatión Transferasa/sangre , Humanos , India , Peroxidación de Lípido/efectos de los fármacos , Linfocitos/efectos de los fármacos , Linfocitos/enzimología , Masculino , Persona de Mediana Edad , Conformación de Ácido Nucleico/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Oxidorreductasas/sangre , Carbonilación Proteica/efectos de los fármacos , Especies Reactivas de Oxígeno/sangre , Contaminación Química del Agua/estadística & datos numéricos
10.
Indian J Exp Biol ; 46(10): 690-7, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19024166

RESUMEN

Chronic arsenic exposure causes skin diseases, gastrointestinal and neurological disorders, diabetes and cancer in various organs. Oxidative stress associated with arsenic exposure cause genetic instabilities and may initiate carcinogenesis. Phytochemicals present in vegetables, fruits, spices, tea, and medicinal plants, have shown to suppress experimental carcinogenesis in various organs. The aim of the present study was to elucidate the protective effect of some of the phytochemicals against the arsenite induced DNA damage in normal mammalian V79 cells. Comet assay was used for assessment of DNA damage and 2', 7'-dichlorofluorescein dihydroacetate for estimation of ROS generated by arsenite. The effect of the phytochemicals was observed during simultaneous treatment with arsenic, before arsenite exposure and during repair experiments. Of all the phytochemicals tested against arsenic, curcumin gave better protection during simultaneous treatment and resveratrol during pre treatment, which was evident both from comet assay and ROS generation experiments. During pre treatment a longer duration of treatment with lower dose of phytochemicals proved fruitful in reducing the genotoxicity. During repair experiments the phytochemicals enhanced recovery of DNA damage and ellagic acid gave promising results. The results indicated that natural phytochemicals may have the efficacy in reducing arsenic induced genotoxicity, in scavenging ROS and in enhancing the process of DNA repair in V79 cells.


Asunto(s)
Arsenitos/antagonistas & inhibidores , Arsenitos/toxicidad , Dieta , Mutágenos/toxicidad , Animales , Capsaicina/farmacología , Línea Celular , Ensayo Cometa , Cricetinae , Cricetulus , Curcumina/farmacología , Daño del ADN , Ácido Elágico/farmacología , Flavonoides/farmacología , Especies Reactivas de Oxígeno/metabolismo , Resveratrol , Estilbenos/farmacología
11.
J Clin Biochem Nutr ; 41(1): 32-42, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18392098

RESUMEN

Chronic exposure of humans to high concentrations of arsenic in drinking water is associated with skin lesions, peripheral vascular disease, hypertension, blackfoot disease and a high risk of cancer. Arsenic induces single strand breaks, DNA-protein crosslinks and apurinic sites in DNA, which are prerequisites for induction of cancer. Amelioration of such damages with natural compounds could be an effective strategy to combat arsenic toxicity. Curcumin is the active ingredient of turmeric, a common household spice, which is a rich source of polyphenols and this compound has been extensively studied as a chemopreventive agent against many types of cancer. The present study investigates whether curcumin could counteract the DNA damage caused by arsenic as assessed by single cell gel electrophoresis (SCGE) using peripheral blood lymphocytes, from healthy donors. It was observed that DNA damage induced by arsenic could be efficiently reduced by curcumin and the effect was more pronounced when lymphocytes were pre-incubated with curcumin prior to arsenic insult. Arsenic caused DNA damage by generation of reactive oxygen species (ROS) and enhancement of lipid peroxidation levels. Curcumin counteracted the damage by quenching ROS, decreasing the level of lipid peroxidation and increasing the level of phase II detoxification enzymes like catalase, superoxide dismutase and glutathione peroxidase. Curcumin also enhanced the DNA repair activity against arsenic induced damage. The expression of polymerase, a repair enzyme, was found to be highly elevated when arsenite induced damaged cells were allowed to repair in presence of curcumin. Results indicate that curcumin has significant role in confronting the deleterious effect caused by arsenic, which could be an economic mode of arsenic mitigation among rural population in West Bengal, India.

12.
J Environ Pathol Toxicol Oncol ; 26(3): 207-20, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18197836

RESUMEN

The groundwater arsenicals have brought dreadful misery for the people residing in the endemic regions of West Bengal, India. Arsenic-related anomalies include arsenicosis, hyperkera-tosis, gastric complications, liver fibrosis, peripheral neuropathy, and cancer. Some of these diseases have been frequently associated with overproduction of reactive oxygen species that cause DNA damage and improper functioning of body's antioxidant defense mechanism. Natural polyphenols present in tea serve as excellent antioxidants. In the present study, an attempt has been made to elucidate the role of representative polyphenols and extracts of green and black tea in modulating sodium arsenite (As III)-induced DNA damage in normal human lymphocytes. Comet assay was used to detect the DNA damage. Arsenic-induced oxidative stress was measured with generation of reactive oxygen species, lipid peroxidation, and activity of some antioxidant enzymes. Expression of some repair enzymes such as poly(ADP-ribose) polymerase and DNA polymerase beta was measured to assess the effect of tea on DNA repair. Tea afforded efficient reduction of As III-induced DNA damage in human lymphocytes. Tea also quenched the excessive production of reactive oxygen species by arsenic, reduced the elevated levels of lipid peroxidation, and increased the activity of antioxidant enzymes such as catalase, superoxide dismutase, and glutathione peroxidase. Furthermore, tea enhanced recovery of DNA damage, which was indicative of repair as confirmed by unscheduled DNA synthesis and pronounced expression of DNA repair enzyme poly(ADP-ribose) polymerase. It is speculated that the antioxidant potential and repair-inducing capacity of tea might help in combating the severe genotoxic effects induced by arsenic in the human population.


Asunto(s)
Antioxidantes/farmacología , Arsénico/toxicidad , Linfocitos/efectos de los fármacos , Extractos Vegetales/farmacología , Té/química , Adulto , Intoxicación por Arsénico/prevención & control , Camellia sinensis/química , Células Cultivadas , Ensayo Cometa , Daño del ADN/efectos de los fármacos , Flavonoides/farmacología , Humanos , Masculino , Estrés Oxidativo/efectos de los fármacos , Fenoles/farmacología , Polifenoles , Especies Reactivas de Oxígeno
13.
Asian Pac J Cancer Prev ; 7(2): 201-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16839211

RESUMEN

Programmed cell death or apoptosis is a physiological process by which genetically damaged cells or undesired cells can be eliminated. Various morphological and molecular changes undergoing during the process of apoptosis are the formation of apoptotic blebs of the cell membrane, cell shrinkage, condensation of chromatin and the disruption of deoxyribonucleic acid (DNA) into typical fragments of multiples of 180 base pairs. These changes can be detected in a number of ways. DNA ladder formation, which is observed following gel electrophoresis technique although is widely accepted but does not reflect the DNA breakdown in individual cell and also may miss contributions from small sub-populations in a heterogeneous cell population. Alkaline comet assay as measured by single cell gel electrophoresis, on the other hand, accurately measures DNA fragmentation on a single cell level and allows analysis of subpopulation of cells. The assay was originally developed for measuring DNA damage of cells exposed to any genotoxic agent. However, the comet image generated by an apoptotic cell is different from that obtained with a cell treated for a short time with a genotoxic agent. Correlation of comet formation with various other established parameters of apoptosis is very important. The present study aims to correlate different features of apoptosis with the formation of comet tail in human leukemia K-562 cells using tea extracts. Apoptosis as measured by formation of apoptotic bodies, flow cytometric analysis, activation of caspase 3 and 8, and expressions of apoptosis related genes such as bcl-2 and bax showed high degree of correlation with comet tail moment. This indicates that comet assay can accurately reflect measure of DNA fragmentation and hence can be used to detect a cell undergoing apoptosis.


Asunto(s)
Apoptosis , Camellia sinensis , Ensayo Cometa , Leucemia Eritroblástica Aguda/patología , Extractos Vegetales , Proteínas Reguladoras de la Apoptosis/metabolismo , Técnicas de Cultivo de Célula , Citometría de Flujo , Humanos , Células K562 , Leucemia Eritroblástica Aguda/metabolismo , Reproducibilidad de los Resultados
14.
Cancer Lett ; 230(1): 111-21, 2005 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-16253767

RESUMEN

Treatment of human leukemic cell lines HL-60 and K-562 with extracts of green and black tea and their polyphenols epigallocatechin gallate and theaflavins, respectively, showed a dose dependent inhibition of growth as a result of cytotoxicity and suppression of cell proliferation. Based on the IC50 values obtained from cytotoxicity data it was clearly evident that black tea was as efficient as green tea. Analysis of polyphenol contents of tea extracts revealed that not only epigallocatechin gallate, which is a predominant polyphenol of green tea, but also theaflavin that is abundantly present in black tea affords significant chemotherapeutic action by imparting cytotoxicity to human leukemic cells. Electrophoretic analysis of fragmented DNA from treated cells displayed characteristic ladder pattern. Flow cytometric analysis revealed the dose dependent increase in sub-G1 peak. These criteria confirmed that cytotoxic activity of green and black tea was due to induction of apoptosis. Such induction was found to be mediated through activation of caspases 3 and 8, particularly caspase 3 and by altering apoptosis related genes as evident by down-regulation of Bcl-2 and up-regulation of Bax proteins.


Asunto(s)
Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Biflavonoides/farmacología , Catequina/farmacología , Té/química , Caspasa 3 , Caspasa 8 , Caspasas/efectos de los fármacos , Caspasas/metabolismo , Regulación hacia Abajo , Flavonoides/análisis , Flavonoides/farmacología , Citometría de Flujo , Genes bcl-2 , Células HL-60 , Humanos , Fenoles/análisis , Fenoles/farmacología , Polifenoles , Proteína X Asociada a bcl-2
15.
J Environ Pathol Toxicol Oncol ; 24(2): 115-28, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15831084

RESUMEN

Induction of apoptosis is an important approach to cancer control. Apart from morphological changes in cells, apoptosis is characterized by fragmentation of nuclear DNA. The characteristic DNA ladder formation that is observed on gel electrophoresis does not reflect the DNA breakdown in individual cells; contributions from small subpopulations are usually overlooked. On the other hand, alkaline comet assay as measured by single cell gel electrophoresis accurately measures DNA fragmentation at a single cell level. The comet assay was originally developed as a cytogenetic test to measure the genotoxicity of various chemicals. However, the comet image generated by an apoptotic cell is different from that obtained with a cell treated for a short time with a genotoxic agent. In the present study using human leukemic cells, typical apoptotic features such as morphological characteristics, FACS analysis, caspase activation, and expression of apoptosis-related genes as induced by tea polyphenols have been found to correlate with the comet tail formation. It is apparent from the high degree of correlation observed between the comet tail moment and each parameter of apoptosis that the comet assay can accurately reflect the measure of DNA fragmentation and, hence, can be used to detect a cell undergoing apoptosis.


Asunto(s)
Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Catequina/análogos & derivados , Ensayo Cometa , Flavonoides/farmacología , Fenoles/farmacología , , Biflavonoides/farmacología , Caspasa 3 , Caspasa 8 , Caspasas/metabolismo , Catequina/farmacología , Citometría de Flujo , Células HL-60 , Humanos , Células K562 , Polifenoles
16.
J Environ Pathol Toxicol Oncol ; 24(2): 129-40, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15831085

RESUMEN

Since the early 1980s, an alarming problem of groundwater arsenic (As) contamination has devastated many districts of West Bengal in India. People drinking As-contaminated water have been suffering severe health problems such as hyperkeratosis, blackfoot disease, neuropathy, and cancer of various sites. DNA damage and genetic instability induced by the inorganic arsenicals present in water are thought to be prerequisites for the initiation of carcinogenesis. Many natural polyphenols, which are consumed through our daily diet, possess excellent cancer chemopreventive properties. Tea, a popular beverage worldwide and rich in polyphenols, has exhibited many health benefits. The present study was conducted to examine the anticlastogenic action of tea extracts (both green and black) against the As-induced chromosomal aberrations. We also evaluated the role of tea in inducing antioxidant enzymes such as superoxide dismutase and catalase to provide protection against the oxidative stress induced by As. Our results demonstrated that tea extracts, particularly Darjeeling tea extract, are effective in counteracting the clastogenicity (chromatid breaks, in particular) of the most potent form of As, sodium arsenite. The antioxidant function of tea in reducing clastogenicity may be partly due to the induction of phase II detoxification enymes, such as superoxide dismutase and catalase. Our results suggest that the use of tea may be an effective approach in combating the health crisis generated by As.


Asunto(s)
Antimutagênicos/farmacología , Antioxidantes/farmacología , Arsenitos , Catequina/análogos & derivados , Aberraciones Cromosómicas/inducido químicamente , Reparación del ADN , Compuestos de Sodio , , Contaminantes Químicos del Agua , Animales , Arsenitos/antagonistas & inhibidores , Biflavonoides/análisis , Camellia sinensis , Catalasa/biosíntesis , Catalasa/metabolismo , Catequina/análisis , Línea Celular , Cricetinae , Cricetulus , Fibroblastos/efectos de los fármacos , Fibroblastos/ultraestructura , Extractos Vegetales/química , Extractos Vegetales/farmacología , Compuestos de Sodio/antagonistas & inhibidores , Superóxido Dismutasa/biosíntesis , Superóxido Dismutasa/metabolismo
17.
J Environ Pathol Toxicol Oncol ; 24(1): 45-56, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15715508

RESUMEN

The Gangetic plain of West Bengal, India, has been engulfed by a disastrous environmental calamity of arsenic contamination of the ground water. Chronic arsenic toxicity caused by drinking arsenic-contaminated water has been one of the worst health hazards gradually affecting nine districts of West Bengal since the early 1980s. Over and above hyperpigmentation and keratosis,weakness, burning sensation of the eyes, swelling of the legs, liver fibrosis, chronic lung disease, gangrene of the toes, neuropathy, and skin cancer are other manifestations. Induction of cancer is frequently associated with DNA damage, changes in ploidy of cells, and non-random chromosome aberrations. Counteraction of these genotoxic and cytogenetic abnormalities with natural dietary polyphenols could be a useful strategy to combat arsenic-induced DNA damage and thereby cancer. A review of the literature showed that it is the antioxidant property of tea polyphenols that affords protection against various types of cancer. The present study was conducted to investigate whether the extracts of green tea and black tea (Darjeeling and Assam) as well as their polyphenols could ameliorate this arsenic-induced genotoxicity. The normal mammalian cell culture derived from male Chinese hamster lung fibroblast cells (V79) was used as the test system to assess the genotoxicity by micronucleus assay. The results showed that both green tea and black tea extracts have equal potential in modulating the arsenic-induced genotoxicity. This effect was perhaps induced by the constituent polyphenols present in green and black tea. In addition, the repair activity of the damaged cells was enhanced when treated with these tea extracts and their polyphenols. Thus, tea and its polyphenols may have a promising role in counteracting the devastating effects of arsenic.


Asunto(s)
Antioxidantes/farmacología , Arseniatos/toxicidad , Arsenitos/toxicidad , Ácido Cacodílico/toxicidad , Micronúcleos con Defecto Cromosómico/efectos de los fármacos , Compuestos de Sodio/toxicidad , , Animales , Línea Celular , Cricetinae , Cricetulus , Masculino , Micronúcleos con Defecto Cromosómico/inducido químicamente , Pruebas de Micronúcleos , Extractos Vegetales/farmacología
18.
Phytother Res ; 18(8): 595-600, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15476314

RESUMEN

Tiliacora racemosa and Semecarpus anacardium, the two plants frequently used in Ayurvedic medicine for the treatment of cancerous diseases, have been selected to examine their action in four human tumour cell lines: acute myeloblastic leukaemia (HL-60), chronic myelogenic leukaemia (K-562), breast adenocarcinoma (MCF-7) and cervical epithelial carcinoma (HeLa). In cells grown in appropriate media the ethanol extract of T. racemosa root, the total alkaloids isolated from this organ and S. anacardium nut oil prepared according to the Ayurvedic principle were found to have cytotoxic activity. The alkaloid fraction from T. racemosa had maximum cytotoxicity and was effective against all four cell lines. S. anacardium oil was cytotoxic only in leukaemic cells. These herbal preparations were not cytotoxic towards normal human lymphocytes, suggesting their action is specific for tumour cells. On microscopic examination the cells treated with these agents exhibited characteristic morphological features of apoptosis, such as cell shrinkage, and the formation of apoptotic bodies. Fluorescent staining with propidium iodide revealed distinct chromatin condensation and nuclear fragmentation. The apoptotic index paralleled the cytotoxic parameters, and fragmented DNA extracted free of genomic DNA from treated cells displayed a typical ladder pattern on gel electrophoresis. Apoptosis induced by alkaloids and phenolics, the active principles present in T. racemosa and S. anacardium, respectively, was found to be mediated by the activation of caspases.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Fitoterapia , Extractos Vegetales/farmacología , Aceites de Plantas/farmacología , Plantas Medicinales , Semecarpus , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Frutas , Células HL-60/efectos de los fármacos , Células HeLa/efectos de los fármacos , Humanos , Células K562/efectos de los fármacos , Medicina Ayurvédica , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Aceites de Plantas/administración & dosificación , Aceites de Plantas/uso terapéutico , Raíces de Plantas
19.
Asian Pac J Cancer Prev ; 4(3): 233-7, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14507244

RESUMEN

Arsenic, a naturally ocurring chemical element, is considered hazardous to human health. Inorganic arsenic compounds were found to induce cytotoxicity in Chinese hamster V-79 cells in culture. The arsenite form was more toxic than arsenate. Extracts of green and two varieties of black tea, as well as their principal polyphenols, (-)-epigallocatechingallate and theaflavin, efficiently counteracted the cytotoxic effects of arsenic compounds. On the basis of the amount of tea extract that afforded 50% protection to the cells from arsenic induced cytotoxicity, black tea was found to be as effective as green tea. The protective effect was attributable to the contents of not only (-)-epigallocatechingallate but also of theaflavin, the latter being a predominant polyphenol present in black tea.


Asunto(s)
Arsénico/antagonistas & inhibidores , Citotoxinas/antagonistas & inhibidores , , Animales , Arsénico/toxicidad , Línea Celular Tumoral , Quimioprevención , Cricetinae , Cricetulus , Masculino
20.
Mutat Res ; 523-524: 33-41, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12628501

RESUMEN

Modulation of events characteristic of carcinogenesis or of cancer cells is being emphasized as a rational strategy to control cancer. Green tea polyphenol epigallocatechin gallate (EGCG) has been shown to be highly active as a cancer chemopreventive agent. Certain cellular and molecular events relevant to carcinogenesis are also modified by EGCG. The present investigation was carried out to examine the effects of EGCG on the cytogenetic change and DNA damage induced by toxicant H(2)O(2) and carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in Chinese hamster V-79 cells in culture. Cytogenetic change as evident by the formation of micronuclei and DNA damage in the form of comet tail length during single cell gel electrophoresis was found to be significantly suppressed by EGCG in a dose dependent manner. Cells preincubated with EGCG were protected from subsequent damage by the genotoxic agents. Apoptosis, a highly organized physiological mechanism to eliminate injured or abnormal cells, is also implicated in multistage carcinogenesis. Initiated cells, cells at promotional stage or fully transformed cells can be eliminated through apoptosis. It was observed that EGCG suppressed growth and proliferation of K-562 cells derived from human chronic myelogenic leukemia. Morphological features of treated cells and characteristic DNA fragmentation revealed that the cytotoxicity was due to induction of apoptosis. This was mediated by activation of caspase 3 and caspase 8. Results show that EGCG not only protects normal cells against genotoxic hazard but also eliminate cancer cells through induction of apoptosis.


Asunto(s)
Anticarcinógenos/farmacología , Antimutagênicos/farmacología , Apoptosis/efectos de los fármacos , Catequina/análogos & derivados , Catequina/farmacología , División Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , , Animales , Caspasas/metabolismo , Línea Celular , Ensayo Cometa , Cricetinae , Cricetulus , Relación Dosis-Respuesta a Droga , Humanos , Peróxido de Hidrógeno/farmacología , Células K562 , Pruebas de Micronúcleos
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