Doxorubicin cardiotoxicity and Camellia sinensis cardioprotection determined by speckle-tracking echocardiography

Abstract Doxorubicin (Dox) is a medication used in the treatment of cancerous tumors and hematologic malignancies with potentially serious side effects, including the risk of cardiotoxicity. Flavonoids are plant metabolites with antioxidant properties and can be extracted from Camellia sinensis (CS). The aim of this study is to evaluate the possible cardioprotective effect of CS against injuries induced by Dox in rats. A total of 32 animals were distributed into four groups: (1) control - intraperitoneal injection (I.P.) of 0.5 mL saline weekly and 1.0 mL water by gavage daily; (2) CS - 0.5 mL saline I.P. weekly and 200 mg/kg CS by gavage daily; (3) Dox - 5.0 mg/kg Dox I.P. weekly and 1.0 mL water by gavage daily; and (4) Dox+CS -5.0 mg/kg Dox I.P. weekly and 200 mg/kg CS by gavage daily. Clinical examinations, blood profiles, electrocardiograms, echocardiograms, and histological analyses of hearts were performed over 25 days. The animals in the Dox group showed changes in body weight and in erythrogram, leukogram, electrocardiography, and echocardiography readings. However, animals from the dox+CS group had significantly less change in body weight, improved cardiac function, and showed more preserved cardiac tissue. This study demonstrated that CS prevents dox-induced cardiotoxicity, despite enhancing the cytotoxic effect on blood cells

La actividad antibacteriana de Camellia sinensis comparada con propóleo frente al Streptococcus mutans / Antibacterial activity of Camellia sinensis versus propolis against Streptococcus mutans

RESUMEN Introducción: El té verde (Camellia sinensis) y el propóleo presentan flavonoides, que inhiben el crecimiento, metabolismo y la coagregación del Streptococcus mutans, principal agente causal de la caries dental. Objetivo: Evaluar la actividad antibacteriana in vitro del extracto etanólico del té verde (Camellia sinensis) al 10 por ciento y 20 por ciento comparado con extracto etanólico de propóleo al 10 por ciento y 20 por ciento, frente al crecimiento de cepas de Streptococcus mutans (ATCC 25175). Métodos: Estudio experimental in vitro, longitudinal, prospectivo y comparativo. El universo estuvo constituido por 90 discos de difusión y la muestra por 15 discos embebidos en té verde (Camellia sinensis) o propóleo a diferentes concentraciones, clorhexidina acuosa al 0,12 por ciento y agua destilada. El tamaño de muestra se calculó por fórmula de comparación de medias, después de realizar un estudio piloto. Se colocaron los discos de difusión embebidos en las sustancias sobre agar Mueller Hinton, sembrado con Streptococcus mutans (ATCC 25175), haciendo medición del ancho de los halos inhibitorios a las 24 y 48 h. Se aplicaron pruebas de comparación no paramétricas de Kruskal Wallis y la prueba rangos de Wilcoxon. Resultados: El máximo ancho de halo inhibitorio logrado por clorhexidina acuosa al 0,12 por ciento, extracto etanólico de té verde (Camellia sinensis) al 20 por ciento y extracto etanólico de propóleo al 20 por ciento fue a las 24 h con valores de 10,64 mm ± 0,924 mm, 6,82 mm ± 0,982 mm y 8,36 mm ± 1,286 mm, respectivamente. El extracto etanólico de té verde (Camellia sinensis) al 20 por ciento, presentó diferencias estadísticamente significativas respecto al extracto etanólico de propóleo al 20 por ciento, tanto a las 24 h (p= 0,013), como a las 48 h (p= 0,011). Conclusiones: Frente al crecimiento de cepas de Streptococcus mutans (ATCC 25175), el extracto etanólico de propóleo al 20 por ciento presenta mayor actividad antibacteriana respecto al extracto etanólico de té verde (Camellia sinensis) al 10 por ciento y 20 por ciento, actividad que disminuye con el paso del tiempo(AU)

ABSTRACT Introduction: Green tea (Camellia sinensis) and propolis contain flavonoids which inhibit the growth, metabolism and co-aggregation of Streptococcus mutans, the main causative agent of dental caries. Objective: Evaluate the antibacterial activity in vitro of 10 percent and 20 percent green tea (Camellia sinensis) ethanolic extract versus 10 percent and 20 percent propolis ethanolic extract against the growth of Streptococcus mutans (ATCC 25175) strains. Methods: An in vitro experimental prospective longitudinal comparative study was conducted. The study universe was 90 diffusion disks and the sample was 15 disks soaked up in green tea (Camellia sinensis) or propolis at various concentrations, 0.12 percent aqueous chlorhexidine and distilled water. Sample size was estimated by the comparison of means formula after conducting a pilot study. The diffusion disks soaked up in the substances were placed on Mueller Hinton agar planted with Streptococcus mutans (ATCC 25175) and the width of the inhibition haloes was measured at 24 h and 48 h. Nonparametric Kruskal-Wallis comparison tests and the Wilcoxon rank test were performed. Results: The maximum width of the inhibition halo achieved by 0.12 percent aqueous chlorhexidine, 20 percent green tea (Camellia sinensis) ethanolic extract, and 20 percent propolis ethanolic extract at 24 h was 10.64 mm ± 0.924 mm, 6.82 mm ± 0.982 mm and 8.36 mm ± 1.286 mm, respectively. The 20 percent green tea (Camellia sinensis) ethanolic extract showed statistically significant differences with respect to the 20 percent propolis ethanolic extract, both at 24 h (p= 0.013) and at 48 h (p= 0.011). Conclusions: The 20 percent propolis ethanolic extract displays greater antibacterial activity against the growth of Streptococcus mutans (ATCC 25175) strains than the 10 percent and 20 percent green tea (Camellia sinensis) ethanolic extract. This activity decreases with the passing of time(AU)

Black and white teas as potential agents to combine with amphotericin B and protect red blood cells from amphotericin B-mediated toxicity / Chá preto e branco de Camellia sinensis como potenciais agentes para associar com anfotericina B

Abstract Amphotericin B is a fungicidal substance that is treatment of choice for most systemic fungal infections affecting immunocompromised patients. However, severe side effects have limited the utility of this drug. The aim of this study was to evaluate the antifungal effect of the combination of amphotericin B with black tea or white tea and protective of citotoxic effect. The present study shows that white and black teas have additive effects with amphotericin B against some species Candida. In addition, the combination of white and black tea with amphotericin B may reduce the toxicity of amphotericin B to red blood cells. Our results suggest that white and black tea is a potential agent to combine with amphotericin for antifungal efficacy and to reduce the amphotericin dose to lessen side effects.

Resumo A anfotericina B é o tratamento de escolha para a maioria das infecções fúngicas sistémicas que afetam os doentes imunocomprometidos. No entanto, efeitos secundários graves têm limitado a utilidade desta droga. O objetivo deste estudo foi avaliar o efeito antifúngico da combinação de anfotericina B com chá preto ou chá branco, bem como o efeito citotóxico desta combinação sobre hemáceas. O presente estudo demonstra que o chá branco e preto de Camellia sinensis têm efeitos aditivos com anfotericina B contra algumas espécies de Candida sp. Além disso, a combinação de chá branco e preto com anfotericina B pode reduzir a toxicidade da anfotericina B em hemáceas. Nossos resultados sugerem que o chá branco e preto são agentes potenciais para associação com anfotericina B contribuindo para eficácia antifúngica, bem como redução de toxicidade.

Short-term evaluation of a green tea extract-based mouthrinse / Avaliação de curto prazo de um enxaguatório bucal à base de extrato de chá verde

Introduction: mechanical hygiene is still the best method forthe maintenance of oral health and prevention of biofilm formation. However, mouthrinses have been increasingly used as an adjunct support especially for post-operatory conditions or when periodontal conditions require. In this way, a number of mouthrinses are available, presenting different active ingredients with predominant antimicrobial action. Objectives: the aim of the present study was to evaluate the topical action of a green-tea extract-based mouthwash on gingival tissue. Materials and Methods: a longitudinal double-blind comparison was performed with two groups of patients clinically evaluated and diagnosed as suffering from gingivitis (n= 40). The patients were divided into two groups, according to the mouthrinse used: GT - green tea (concentration of 20mg/ml), and P - placebo, 0.9% saline solution. Clinical examination of the mucosa, tooth staining, plaque and gingival indices were peformed before and 15 days after the continuous use of the products twice a day. Results: no mucosal or tasting alterations were found, neither tooth staining regardless the mouthrinse used. Statistical assessment did not detect differences on gingival indexes between the groups before and after mouthrinses use; however, plaque indexes were significant lower in patients of GT group, compared to the P group. Conclusions: the use of phytotherapic products with active ingredients should be investigated for biofilm control, responsible for the onset and progression of periodontal disease, as well as other various oral pathologies. Considering the period of evaluation pro-posed in this study, relevant decrease in initial phase of plaque for-mation could be observed with the green tea mouthrinse. Further long-term evaluation studies should be carried-out in order to eluci-date its continuous effects on oral structures.

Introdução: higiene mecânica ainda é o melhor método para a manutenção da saúde bucal e prevenção da formação de biofilmes. No entanto, enxagues têm sido cada vez mais usado como um suporte auxiliar especialmente para as condições pós-operatórias ou quando as condições periodontais exigem. Desta forma, um número de bochechos estão disponíveis, apresentando diferentes ingredientes ativos com predominante ação antimicrobiana. Objetivos: o objetivo do presente estudo foi avaliar a ação tópica de um bochecho à base de extrato de chá verde no tecido gengival. Materiais e Métodos: a comparação longitudinal, duplo-cego, foi realizada com dois grupos de pacientes clinicamente avaliados e diagnosticados como portadores de gengivite (n = 40). Os pacientes foram divididos em dois grupos, de acordo com o enxaguatório oral usado: CV - chá verde (concentração de 20 mg / ml), e P - placebo, solução salina a 0,9%. O exame clínico da mucosa, coloração dos dentes, índice de placa e índice gengival foram realizados antes e 15 dias após o uso contínuo dos produtos duas vezes por dia. Resultados: nenhuma alteração na mucosa ou de degustação foi encontrada, assim como não foi identificado modificação na coloração do dente. A Avaliação estatística não detectou diferenças no índice gengival entre os grupos antes e depois de usar enxaguatórios. No entanto, índice de placa inferior foi menor de forma significativa nos pacientes do grupo CV, em comparação com o grupo P. Conclusões: o uso de produtos fitoterápicos com ingredientes ativos deve ser investigado para o controle de biofilme, responsável pelo aparecimento e progressão da doença periodontal. Considerando o período de avaliação proposto, a redução correspondente na fase inicial da formação de placa pôde ser observada com o enxaguatório à base de chá verde. Além disso, estudos de avaliação de longo prazo devem ser realizados, a fim de elucidar seu efeito contínuo em longo prazo sobre as estruturas orais.

Protective role of green tea extract against tamoxifen induced liver injury in albino rats

Tamoxifen [TAM] is a synthetic antiestrogen commonly used to treat breast cancer in women. TAM-induced hepatotoxicity has been described, including toxic hepatitis, massive hepatic steatosis, or multifocal hepatic fatty infiltration. Tea is one of the most popular beverages consumed worldwide. Some studies indicated that green tea prevents hepatotoxicity and has antitumorigenic effects. The aim of the study was to evaluate the protective effects of green tea extract [GTE] against TAM-induced liver injury in rats. Forty adult male albino rats were divided into four groups [10 rats each]: the control group; the green tea group, administered 1.5% GTE orally for 18 days; the TAM group, treated with 45 mg/kg/day of TAM for 7 days; and the TAM and green tea group, administered 1.5% GTE 4 days before and 14 days after TAM treatment. Animals were sacrificed at the end of the experiment. The livers were removed and processed for light microscopic examination. The TAM-treated group showed loss of normal architecture of hepatic lobules, hemorrhage, cholestasis, ballooning degeneration of hepatocytes, steatosis, inflammatory cells infiltration, Kupffer cells hyperplasia, and dilated and congested sinusoids and portal venules. Liver sections of the TAM and green tea-treated group showed normal architecture of hepatic lobules, portal triad, hepatocytes, central vein, and blood sinusoids. Green tea has protective effects against TAM-induced hepatotoxicity

Possible protective effect of camellia sinensis [green tea] against acrylamide induced testicular damage in albino rats

Acrylamide is a proved toxin for testicular function, found in food when heated for long period of time. Green tea [Camellia sinensis] is a potent antioxidant; the aim of this study was to investigate the protective effect of green tea extract against the toxic effects of acrylamide in rat testes. acrylamide was administered orally by gastric gavage to rats in different doses and also the extract of green tea was administered orally to different groups of animals in combination with the acrylamide. The weight of animals, testosterone hormone level and histopathological effects upon testicles were evaluated. Testosterone hormone level in serum was significantly decreased in those with acrylamide toxicity either in low or high dose. The histopatological findings were in the form of thickening of the tubuler epithelium and degenerations of germ cells. All findings significantly improved with the co administration of green tea extract with the acrylamide. Green tea extract reversed all the toxic effects of acrylamide even in high dose for long period [90 days]. green tea extract is a potent antioxidant antidote for the acrylamide toxic effects upon testicular function