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1.
J Biochem Mol Toxicol ; 38(1): e23548, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37867459

RESUMO

Four novel antimony (III) and bismuth(III) complexes of the kind Cl-Sb-O-C(OR)-CH(CH3 )C-NH-(CH2 )2 -NH-C(CH3 )CH:C(OR)-O [where R = -CH3 , M = Sb (1a); R = -C2 H5 , M = Sb (1b); R = -CH3, M = Bi (1c); R = -C2 H5 , M = Bi (1d)] were successfully prepared by reacting antimony(III)chloride and bismuth(III)chloride with sodium salt of ß-enamino esters in 1:1 stoichiometry, which were further structurally characterized by physicochemical and IR, 1 H, 13 C NMR spectral and mass spectrometry. Structural analysis revealed that all four derivatives of both antimony and bismuth display octahedarl geometry which has been optimized through computational studies. These derivatives along with their parent ligands were subsequently assayed in vitro for antibacterial (Bacillus subtilis, Pseudomonas aeruginosa) and antifungal (Aspergillus niger and Candida albicans) activities. Synthesized complexes were more efficacious in terms of biological activities as compared to parent ligands Further synthesized compounds were evaluated for their in vitro cytotoxic activity against lung cancer cell line A549 using MTT method. IC50 value for all four complexes was determined and all of them are found active. Computational studies of the representative complexes have been done using B3LYP/631-G* basis sets to provide optimized geometry.


Assuntos
Anti-Infecciosos , Antineoplásicos , Antimônio/farmacologia , Bismuto/farmacologia , Bismuto/química , Teoria da Densidade Funcional , Cloretos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana
2.
Biometals ; 24(4): 615-28, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21243404

RESUMO

Epidemiological evidence demonstrates positive correlation between environmental and occupational arsenic or fluoride exposure and risk to various cardio-respiratory disorders. Arsenic-exposure has been associated with atherosclerosis, hypertension, cerebrovascular diseases, ischemic heart disease, and peripheral vascular disorders, whereas Fluoride-exposure manifests cardiac irregularities and low blood pressure (BP). Present study aims to study the combined effects of these toxicants on various cardio-respiratory variables in male rats. Single intravenous (i.v.) dose of arsenic (1, 5, 10 mg/kg) or fluoride (5, 10, 20, 36.5 mg/kg) either alone or in combination were administered. Individual exposure to arsenic or fluoride led to a significant depletion of mean arterial pressure, heart rate (HR), respiration rate and neuromuscular (NM) transmission in a dose-dependent manner. These changes were accompanied by increased levels of blood reactive oxygen species (ROS) and decreased glutathione (GSH) concentrations. An increase in the blood acetyl cholinesterase (AChE) activity was observed in both arsenic or fluoride exposed rats. These changes were significantly more pronounced in arsenic-exposed animals than in fluoride. During combined exposure to arsenic (5 mg/kg) + fluoride (20 mg/kg) or arsenic (10 mg/kg) + fluoride (36.5 mg/kg) the toxic effects were more pronounced compared to individual toxicities of arsenic or fluoride alone. However, combined exposure to arsenic (5 mg/kg) + fluoride (36.5 mg/kg) resulted in antagonistic effects on variables suggestive of altered cardio-respiratory function and oxidative stress. The results from the present study suggest that arsenic or fluoride individually demonstrate cardio-respiratory failure at all doses whereas during combination exposure these toxins show variable toxicities; both synergistic and antagonistic effects depending upon the dose. Moreover, it may be concluded that arsenic and/or fluoride cardio-respiratory toxicity may be mediated via oxidative stress. However, these results are new in the discipline thus requires further exploration.


Assuntos
Arsenitos/toxicidade , Doenças Cardiovasculares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Doenças Respiratórias/metabolismo , Compostos de Sódio/toxicidade , Fluoreto de Sódio/toxicidade , Animais , Arsenitos/administração & dosagem , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/induzido quimicamente , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glutationa/sangue , Injeções Intravenosas , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/sangue , Testes de Função Respiratória , Doenças Respiratórias/sangue , Doenças Respiratórias/induzido quimicamente , Compostos de Sódio/administração & dosagem , Fluoreto de Sódio/administração & dosagem
3.
J Family Med Prim Care ; 10(9): 3219-3222, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34760733

RESUMO

BACKGROUND: For recognizing the initial stages of breast cancer, mammography is regarded as one of the best modalities and plays a crucial part to lessen morbidity and mortality. For collaborative studies and planning of preventive strategies, it is significant to have baseline data. Thus, in this survey, the frequency distribution of breast imaging reporting and data system (BIRADS) classification and breast consistencies was investigated during the mammographic screening program in the Gwalior region, India. MATERIAL AND METHODS: A descriptive, cross-sectional survey was conducted in the Gwalior region, India, in which 1,838 patients were screened with the aid of mammography. The mammography films were evaluated by a single radiologist who determined the BIRADS score, breast composition, and any other abnormal findings. After tabulating the data into MS Excel (MS Office version 2007 developed by Microsoft, Redmond, WA), descriptive analysis and Chi-square test were performed to determine the association between the BIRADS score and breast consistency and setting significance level at (below) 0.05. RESULTS: The most commonly found BIRADS score was score 1 (53.4%), followed by score 2 (20.4%), and score 5 was of the least frequency (1.3%). Similarly, the most common consistency found was fatty (48.2%) and the least common was heterogeneously dense (3.97%). The most BIRADS category of 0 was seen in heterogeneously dense (n = 22; 26%) followed by dense breast compositions (n = 18; 25%). The most common consistency found with known breast malignancy (BIRADS 6) patients was the extremely dense breast (n = 11; 40.7%). CONCLUSION: In this study, it was observed that about 57.3% of all the cases were categorized as BIRADS 1 and 20.8% as BIRADS 2.

4.
Indian J Med Res ; 128(4): 501-23, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19106443

RESUMO

Exposure to heavy metals is a common phenomenon due to their environmental pervasiveness. Metal intoxication particularly neurotoxicity, genotoxicity, or carcinogenicity is widely known. This review summarizes our current understanding about the mechanism by which metalloids or heavy metals (particularly arsenic, lead, cadmium and mercury) induce their toxic effects. The unifying factor in determining toxicity and carcinogenicity for all these metals is the generation of reactive oxygen and nitrogen species. The toxic manifestations of these metals are caused primarily due to imbalance between pro-oxidant and antioxidant homeostasis which is termed as oxidative stress. Besides these metals have high affinity for thiol groups containing enzymes and proteins, which are responsible for normal cellular defense mechanism. Long term exposure to these metals could lead to apoptosis. Signaling components affected by metals include growth factor receptors, G-proteins, MAP kinases and transcription factors. Chelation therapy with chelating agents like calcium disodium ethylenediamine tetra acetic acid (CaNa(2)EDTA), British Anti Lewisite (BAL), sodium 2,3-dimercaptopropane 1-sulfonate (DMPS), meso 2,3-dimercaptosuccinic acid (DMSA) etc., is considered to be the best known treatment against metal poisoning. Despite many years of research we are still far away from effective treatment against toxicity caused due to exposure to heavy metals/metalloids. The treatment with these chelating agents is compromised with number of serious side-effects. Studies show that supplementation of antioxidants along-with a chelating agent prove to be a better treatment regimen than monotherapy with chelating agents. This review attempts a comprehensive account of recent developments in the research on heavy metal poisoning particularly the role of oxidative stress/free radicals in the toxic manifestation, an update about the recent strategies for the treatment with chelating agents and a possible beneficial role of antioxidants supplementation to achieve the optimum effects. We have selected only arsenic, lead, mercury and cadmium for this article keeping in view current concerns and literature available.


Assuntos
Quelantes/química , Metais Pesados/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Animais , Humanos , Metais Pesados/química
5.
Metallomics ; 10(9): 1291-1306, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30140832

RESUMO

INTRODUCTION: Arsenic and fluoride are recognized globally as the most serious inorganic contaminants in drinking water. As there is no safe and effective treatment for the cases of fluoride poisoning and combined arsenic-fluoride toxicity, the present study was planned to assess (i) the mechanism of combined exposure to arsenic and fluoride via biochemical and spectroscopic data; (ii) the effect of a thiol chelating agent, meso-2,3-dimercaptosuccinic acid (DMSA), either individually or in combination with the antioxidant vitamin C in reversing arsenic-fluoride toxicity; and (iii) whether combination therapy enhances arsenic and fluoride removal from blood and soft tissues. METHODS: Rats were exposed to arsenic (50 mg l-1) and fluoride (50 mg l-1) individually and in combination for 9 months and later administered DMSA (50 mg kg-1) via an i.p. route and vitamin C (25 mg kg-1) orally for 5 days. Biochemical parameters suggestive of alterations in the heme synthesis pathway, oxidative stress in blood, the liver and the kidneys, and concentrations of arsenic and fluoride in blood and soft tissues were studied. We also studied the infrared (IR) spectra of DNA extracted from the livers and kidneys of the normal and exposed animals. RESULTS: It was found that chronic arsenic and fluoride exposure led to an increased oxidative stress condition and impaired heme synthesis (67% inhibition in δ-aminolevulinic acid dehydratase activity and 38% increase in δ-aminolevulinic acid synthetase activity). The decreased antioxidant defense mechanism was marked by a 2.25 fold increased concentration of Reactive Oxygen Species (ROS) and a 28% decrease in the Glutathione (GSH) level. Interestingly, concomitant exposure to arsenic and fluoride did not lead to antagonistic effects as the toxic effects were the same as those seen during the individual exposure to both the toxicants. It suggests that toxicity depends on the dose and duration of exposure. Combination therapy with DMSA and vitamin C showed a better efficacy than monotherapy in terms of reducing the arsenic and fluoride burden (more than 70% in blood and soft tissues) as well as reversal in the altered biochemical variables indicative of oxidative stress and tissue damage (80-85%). The infrared (IR) spectra of DNA isolated from the liver and kidneys suggested that the treatment with vitamin C and DMSA had no beneficial effects in terms of reversing DNA damage. CONCLUSION: On the basis of the above observations, we suggest that the combinational therapy of DMSA and vitamin C would be more effective in arsenic and/or fluoride toxicity; however, more detailed studies are required to address recoveries in DNA damage.


Assuntos
Arsênio/toxicidade , Ácido Ascórbico/uso terapêutico , Fluoretos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Succímero/uso terapêutico , Animais , Antígenos CD13/sangue , Catalase/metabolismo , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , Glucosefosfato Desidrogenase/metabolismo , Glutamil Aminopeptidase/sangue , Glutationa/sangue , Dissulfeto de Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Sintase do Porfobilinogênio/sangue , Sintase do Porfobilinogênio/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/sangue , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
6.
Chem Biol Interact ; 162(2): 128-39, 2006 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-16828073

RESUMO

Arsenic and fluoride are potent toxicants, widely distributed through drinking water and food and often result in adverse health effects. The present study examined the effects of sodium meta-arsenite (100 mg/l in drinking water) and sodium fluoride (5 mg/kg, oral, once daily), administered either alone or in combination for 8 weeks, on various biochemical variables indicative of tissue oxidative stress and cell injury in Swiss albino male mice. A separate group was first exposed to arsenic for 4 weeks followed by 4 weeks of fluoride exposure. Exposure to arsenic or fluoride led to a significant depletion of blood delta-aminolevulinic acid dehydratase (ALAD) activity and glutathione (GSH) level. These changes were accompanied by increased level of blood and tissues reactive oxygen species (ROS) level. An increase in the level of liver and kidney thiobarbituric acid reactive substance (TBARS) along with a concomitant decrease in the activities of superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPx) and reduced GSH content were observed in both arsenic and fluoride administered mice. The changes were significantly more pronounced in arsenic exposed animals than in fluoride. It was interesting to observe that during combined exposure the toxic effects were less pronounced compared to the effects of arsenic or fluoride alone. In some cases antagonistic effects were noted following co-exposure to arsenic and fluoride. Arsenic and fluoride concentration increased significantly on exposure. Interestingly, their concentration decreased significantly on concomitant exposure for 8 weeks. However, the group which was administered arsenic for 4 weeks followed by 4 weeks of fluoride administration showed no such protection suggesting that the antagonistic effect of fluoride on arsenic or vice versa is possible only during interaction at the gastro intestinal sites. These results are new and interesting and require further exploration.


Assuntos
Arsênio/metabolismo , Arsenitos/farmacologia , Fluoretos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Compostos de Sódio/farmacologia , Fluoreto de Sódio/farmacologia , Alanina Transaminase/metabolismo , Animais , Arsênio/sangue , Arsenitos/administração & dosagem , Arsenitos/toxicidade , Aspartato Aminotransferases/metabolismo , Contagem de Células Sanguíneas , Catalase/metabolismo , Eritrócitos/química , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Fluoretos/sangue , Glucose-6-Fosfatase/metabolismo , Glutationa/sangue , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Hematócrito , Rim/efeitos dos fármacos , Rim/enzimologia , Rim/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Camundongos , Monoéster Fosfórico Hidrolases/metabolismo , Sintase do Porfobilinogênio/sangue , Espécies Reativas de Oxigênio/sangue , Compostos de Sódio/administração & dosagem , Compostos de Sódio/toxicidade , Fluoreto de Sódio/administração & dosagem , Fluoreto de Sódio/toxicidade , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
7.
J Oral Maxillofac Pathol ; 19(3): 379-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26980969

RESUMO

Follicular lymphoma (FL) is a common form of non-Hodgkin's lymphoma (NHL) with the ability to transform into a more aggressive disease, frequently to B cell-lymphoblastic lymphoma. Diffuse large B-cell lymphoma (DLBCL) is a subtype of NHL, which is characterized by diffuse proliferation of large neoplastic B-lymphocytes. It accounts for 30% of all NHL and its occurrence in the mandible is very rare. It is often seen in young adults, but in the present case, a 50-year-old male patient presented with painless swelling in left lower jaw since 25 days following extraction of left lower molar teeth. There was a history of fever and submandibular lymph nodes were enlarged. On incisional biopsy, features of NHL-like lesion were observed and confirmed by immunohistochemistry using CD20, bcl-2, CD10, CD3, CD5, Ki67 markers to be FL (3A) lymphoma transforming into DLBCL. This is a very uncommon presentation.

8.
Rev Recent Clin Trials ; 10(4): 289-97, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26411952

RESUMO

CONTEXT: Vaginal cancer is a rare gynecologic cancer with very little documentation. OBJECTIVE: Literature search to have useful information for the management of vaginal cancer and share. MATERIAL METHODS: We have searched the PUBMED database, Google search engine and other database. A total of 26 references were taken into account. COMMENTS: Once spread from primary other cancers or vulva is ruled out, vaginal cancer is designated to be primary in origin. It was revealed that majority of vaginal cancers reported are squamous cell carcinomas. The most common risk factors implicated are Human Papiloma Virus, age. Most common presenting symptoms were abnormal vaginal bleeding,. Diagnosis requires pathological confirmation. Management depends on staging work-up. Vaginal cancer is staged by FIGO system of staging and TNM staging. There are many prognostic factors influencing the choice of treatment. Lymph node metastasis is one of the important prognostic factors, others to mention are histology, size, age. In a recent SEER analysis of over 2000 patients, the 5 year disease specific survival was 84% for stage 1, 75% for stage II and 57% for advanced tumors. Early carcinomas are generally treated with either surgery or radiation therapy. Advanced cancers are treated with radiation therapy with simultaneous administration of combined chemotherapy. Preventive strategies include safe sex and HPV vaccination. CONCLUSION: Primary vaginal cancer is a rare entity, if there is no history of cancer cervix or vulva in past or absence of cervical squamous cell carcinoma or vulvar carcinoma within 5 years is usually considered as primary vaginal cancer. Though early stage vaginal cancers have better outcome treated with surgery or radiotherapy or surgery followed by radiotherapy, radiotherapy alone is preferred mode of treatment in vaginal cancers.


Assuntos
Carcinoma de Células Escamosas/patologia , Infecções por Papillomavirus/patologia , Neoplasias Vaginais/patologia , Neoplasias Vaginais/virologia , Adulto , Biópsia por Agulha , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Incidência , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Prognóstico , Doenças Raras , Medição de Risco , Programa de SEER , Resultado do Tratamento , Neoplasias Vaginais/epidemiologia , Neoplasias Vaginais/terapia
9.
Patholog Res Int ; 2015: 840739, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26457223

RESUMO

Background. Oral squamous cell carcinoma is the sixth most frequent malignant tumor worldwide and the third most common cancers in developing countries. Oral leukoplakia is the best-known precursor lesion of oral squamous cell carcinoma. The aim of the present study was to compare immunohistochemical expression of antiapoptotic protein survivin in normal oral mucosa, oral leukoplakia, and oral squamous cell carcinoma. Method. Total 45 specimens of formalin fixed paraffin embedded tissue blocks, 15 in each of the following: normal oral mucosa, leukoplakia, and oral squamous cell carcinoma were used for the study. Immunohistochemical reaction for survivin protein was performed for the 4 µm thick histological sections taken on positively charged slides. Results. 20% normal mucosa cases, 53.33% cases of leukoplakia, and 80% of oral squamous cell carcinoma were found out to be survivin positive. One way ANOVA test indicated statistically significant difference of survivin expression between the three different groups (p < 0.001). Conclusion. A high incidence of survivin protein expression in oral epithelial dysplasia and squamous cell carcinoma samples indicate that survivin protein expression may be an early event in initiation and progression of oral squamous cell carcinoma.

10.
Curr Med Chem ; 20(36): 4540-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24206124

RESUMO

Heavy metals are known to cause oxidative deterioration of bio-molecules by initiating free radical mediated chain reaction resulting in lipid per-oxidation, protein oxidation and oxidation of nucleic acid like DNA and RNA. The development of effective dual functioning antioxidants, possessing both metal-chelating and free radical-scavenging properties should bring into play. Administration of natural and synthetic antioxidants like, quercetin, catechin, taurine, captopril, gallic acid, melatonin, N-acetyl cysteine, α- lipoic acid and others have been recognized in the disease prevention and clinical recovery against heavy metal intoxication. These antioxidants affect biological systems not only through direct quenching of free radicals but also via chelation of toxic metal(s). These antioxidants also, have the capacity to enhance cellular antioxidant defense mechanism by regenerating endogenous antioxidants, such as glutathione and vitamin C and E. They also influence cellular signaling and trigger redox sensitive regulatory pathways. The reactivity of antioxidants in protecting against heavy metal induced oxidative stress depends upon their structural properties, their partitioning abilities between hydrophilic and lipophilic environment and their hydrogen donation antioxidant properties. Herein, we review the structural, biochemical and pharmacological properties of selected antioxidants with particular reference to their ability to (i) chelate heavy metals from its complex (ii) ameliorate free radical (iii) terminate heavy metal induced free radical chain reaction (iv) regenerate endogenous antioxidants and, (v) excretion of metal without its redistribution.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Quelantes/química , Quelantes/farmacologia , Terapia por Quelação/métodos , Intoxicação por Metais Pesados , Intoxicação/tratamento farmacológico , Animais , Radicais Livres/química , Humanos , Estresse Oxidativo/efeitos dos fármacos
11.
Metallomics ; 4(1): 78-90, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21986897

RESUMO

Arsenic and fluoride are major contaminants of drinking water. Mechanisms of toxicity following individual exposure to arsenic or fluoride are well known. However, it is not explicit how combined exposure to arsenic and fluoride leads to cellular and/or DNA damage. The present study was planned to assess (i) oxidative stress during combined chronic exposure to arsenic and fluoride in drinking water, (ii) correlation of oxidative stress with cellular and DNA damage and (iii) mechanism of cellular damage using IR spectroscopy. Mice were exposed to arsenic and fluoride (50 ppm) either individually or in combination for 28 weeks. Arsenic or fluoride exposure individually led to a significant increase in reactive oxygen species (ROS) generation and associated oxidative stress in blood, liver and brain. Individual exposure to the two toxicants showed significant depletion of blood glutathione (GSH) and glucose 6-phosphate dehydrogenase (G6PD) activity, and single-stranded DNA damage using a comet assay in lymphocytes. We also observed an increase in the activity of ATPase, thiobarbituric acid reactive substance (TBARS) and a decreased, reduced and oxidized glutathione (GSH : GSSG) ratio in the liver and brain. Antioxidant enzymes like superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) were decreased and increased in liver and brain respectively. The changes were more pronounced in liver compared to brain suggesting liver to be more susceptible to the toxic effects of arsenic and fluoride. Interestingly, combined exposure to arsenic and fluoride resulted in less pronounced toxic effects compared to their individual effects based on biochemical variables, IR spectra, DNA damage (TUNEL and comet assays) and histopathological observations. IR spectra suggested that arsenic or fluoride perturbs the strength of protein and amide groups; however, the shifts in peaks were not pronounced during combined exposure. These results thus highlight the role of arsenic- or fluoride-induced oxidative stress, DNA damage and protein interaction as the major determinants of toxicity, along with the differential toxic effects during arsenic-fluoride interaction during co-exposure. The study further corroborates our earlier observations that at the higher concentration co-exposures to these toxicants do not elicit synergistic toxicity.


Assuntos
Arsênio/toxicidade , Dano ao DNA/efeitos dos fármacos , Fluoretos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Adenosina Trifosfatases/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Distribuição Aleatória , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
12.
J Neurol Sci ; 285(1-2): 198-205, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19635623

RESUMO

We studied the effects of combined exposure to arsenic and fluoride on (i) brain biogenic amines, oxidative stress and its correlation with glutathione and linked enzymes; (ii) alterations in the structural integrity of DNA; and (iii) brain and blood arsenic and fluoride levels. Efficacy of alpha-tocopherol in reducing these changes was also determined. Male mice were exposed to sodium meta arsenite (50 ppm) and sodium fluoride (50 ppm) individually and in combination for ten weeks. Animals were given vitamin E supplementation (5 mg/kg, i.m., alternate days) throughout the experiment. Exposure to arsenic and fluoride significantly decreased the levels of brain biogenic amines. However; acetyl cholinesterase (AChE) and monoamine oxidase (MAO) activities showed an increase on fluoride exposure. There was also an increase in reactive oxygen species, thiobarbituric acid reactive species level, glutathione S-transferase and glutathione peroxidase activities and decreased superoxide dismutase activity, GSH:GSSG ratio, glucose 6-phosphate dehydrogenase activity. Combined exposure to these toxicants produced more pronounced effects on AChE, MAO, SOD and catalase activities. Infrared spectra showed less toxicity during combined exposure as the characteristic peaks of cytosine and alpha-helical structure of DNA were observed in normal and arsenic plus fluoride-exposed animals. Vitamin E reduced brain fluoride level and tissue oxidative stress but had no effect on arsenic. Combined exposure to arsenic and fluoride does not necessarily lead to more pronounced toxicity and interestingly exhibit some antagonistic effects. Vitamin E supplementation may be of added value in reverting some of the toxic effects.


Assuntos
Arsenitos/toxicidade , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Fármacos do Sistema Nervoso Central/toxicidade , Compostos de Sódio/toxicidade , Fluoreto de Sódio/toxicidade , Animais , Arsenitos/sangue , Arsenitos/metabolismo , Aminas Biogênicas/metabolismo , Encéfalo/enzimologia , Fármacos do Sistema Nervoso Central/sangue , Fármacos do Sistema Nervoso Central/metabolismo , DNA/metabolismo , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/fisiologia , Glutationa/metabolismo , Masculino , Camundongos , Conformação de Ácido Nucleico/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Distribuição Aleatória , Compostos de Sódio/sangue , Compostos de Sódio/metabolismo , Fluoreto de Sódio/sangue , Fluoreto de Sódio/metabolismo , Vitamina E/administração & dosagem
13.
Oxid Med Cell Longev ; 1(1): 39-45, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19794907

RESUMO

Arsenic is a naturally occurring element that is ubiquitously present in the environment. High concentration of naturally occurring arsenic in drinking water is a major health problem in different parts of the world. Despite arsenic being a health hazard and a well documented carcinogen, no safe, effective and specific preventive or therapeutic measures are available. Among various recent strategies adopted, administration of an antioxidant has been reported to be the most effective. The present study was designed to evaluate the therapeutic efficacy of monoisoamyl dimercaptosuccinic acid (MiADMSA), administered either individually or in combination with taurine post chronic arsenic exposure in rats. Arsenic exposed male rats (25 ppm, sodium arsenite in drinking water for 24 weeks) were treated with taurine (100 mg/kg, i.p., once daily), monoisoamyl dimercaptosuccinic acid (MiADMSA) (50 mg/kg, oral, once daily) either individually or in combination for 5 consecutive days. Biochemical variables indicative of oxidative stress along-with arsenic concentration in blood, liver and kidney were measured. Arsenic exposure significantly reduced blood delta-aminolevulinic acid dehydratase (ALAD) activity, a key enzyme involved in the heme biosynthesis and enhanced zinc protoporphyrin (ZPP) level. Clinical hematological variables like white blood cells (WBC), mean cell hemoglobin (MCH), and mean cell hemoglobin concentration (MCHC) showed significant decrease with a significant elevation in platelet (PLT) count. These changes were accompanied by significant decrease in superoxide dismutase (SOD) activity and increased catalase activity. Arsenic exposure caused a significant decrease in hepatic and renal glutathione (GSH) level and an increase in oxidized glutathione (GSSG). These biochemical changes were correlated with an increased uptake of arsenic in blood, liver and kidney. Administration of taurine significantly reduced hepatic oxidative stress however co-administration of a higher dose of taurine (100 mg/kg) and MiADMSA provided more pronounced effects in improving the antioxidant status of liver and kidney and reducing body arsenic burden compared to the individual treatment of MiADMSA or taurine. The results suggest that in order to achieve better effects of chelation therapy, co-administration of taurine with MiADMSA might be preferred.


Assuntos
Intoxicação por Arsênico/prevenção & controle , Arsênio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Succímero/análogos & derivados , Taurina/farmacologia , Animais , Antídotos/farmacologia , Arsênio/sangue , Arsênio/metabolismo , Intoxicação por Arsênico/sangue , Intoxicação por Arsênico/metabolismo , Quelantes/farmacologia , Masculino , Ratos , Ratos Wistar , Succímero/farmacologia , Taurina/metabolismo
14.
Drug Chem Toxicol ; 30(3): 263-81, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17613011

RESUMO

Arsenic and fluoride are common environmental contaminants. Coexposure to these elements can occur through groundwater. We investigated the effects of sodium meta arsenite (50 mg/L in drinking water) and sodium fluoride (50 mg/L in drinking water) individually and in combination. Biochemical parameters suggestive of alterations in heme synthesis pathway, oxidative stress in liver and kidneys, and concentration of essential metals in blood and soft tissues were studied in Swiss albino male mice given the chemicals for 3 weeks. The possible beneficial effect of vitamin E administration (25 mg/kg, oral, alternate days after arsenic/fluoride exposure) on the above variables was investigated. Exposure to arsenic or fluoride caused a significant depletion in blood delta-aminolevulinic acid dehydratase (ALAD) activity, platelet counts (PLT), and glutathione (GSH) level. Blood white blood cell (WBC) counts also decreased. These changes were accompanied by increased reactive oxygen species (ROS) levels. Arsenic and fluoride exposure led to a significant depletion of super oxide dismutase (SOD) activity with no effect on catalase and glutathione peroxidase (GPx) activities. Combined exposure to these toxicants had no synergistic effect on blood ALAD activity and WBC counts, and the effects seen appeared to result predominantly from arsenic. Hepatic catalase activity, on the other hand, increased significantly on exposure to arsenic and fluoride. There was only moderate antagonistic effect on arsenic and fluoride concentration in blood and liver, and kidney arsenic concentration was less pronounced during coexposure compared with arsenic alone. Interestingly, fluoride concentration showed less pronounced uptake during concomitant exposure compared with fluoride exposure alone. Vitamin E supplementation during coexposure to arsenic and fluoride provided only moderate recovery in the altered antioxidant enzymes and in depleting ROS level, but the altered essential metal concentration, particularly calcium level, responded more favorably to vitamin E administration. It can be concluded from the current study that (i) coadministration of arsenic and fluoride was less toxic to the animals compared with individual toxic effects of these toxicants, and (ii) vitamin E supplementation during coexposure had only limited additional beneficial effects in restoring altered biochemical variables, maintaining pro-oxidant/antioxidant balance, and reducing body arsenic store but plays a significant role in maintaining essential metal balance.


Assuntos
Antioxidantes/farmacologia , Arsenitos/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Compostos de Sódio/toxicidade , Fluoreto de Sódio/toxicidade , Poluentes Químicos da Água/toxicidade , alfa-Tocoferol/farmacologia , Animais , Arsenitos/antagonistas & inibidores , Arsenitos/sangue , Arsenitos/metabolismo , Cálcio/sangue , Cálcio/metabolismo , Catalase/metabolismo , Cobre/sangue , Cobre/metabolismo , Glutationa/sangue , Rim/metabolismo , Contagem de Leucócitos , Fígado/metabolismo , Masculino , Camundongos , Contagem de Plaquetas , Sintase do Porfobilinogênio/sangue , Espécies Reativas de Oxigênio/metabolismo , Compostos de Sódio/antagonistas & inibidores , Compostos de Sódio/sangue , Compostos de Sódio/metabolismo , Fluoreto de Sódio/antagonistas & inibidores , Fluoreto de Sódio/sangue , Fluoreto de Sódio/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/antagonistas & inibidores , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/metabolismo , Zinco/sangue , Zinco/metabolismo
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