In vivo and in vitro genotoxicity studies of aqueous extract of Xanthium spinosum

The use of plants as a source of palliative or cure for pathological conditions is quite common worldwide. Xanthium spinosum (Asteraceae), popularly known in Brazil as 'espinho de carneiro', is an annual weed from South America, which has been used by empiric medicine to treat neoplasias. Owing to the extensive use of the above-mentioned plant and to the lack of reports about the real effects of its infusion, current study evaluated the genotoxic potential of its aqueous extract at concentrations 0.02 g L-1, 0.1 g L-1 and 0.2 g L-1 by fish micronucleus test and by comet human leukocytes assay. The micronucleus test featured at least 50 cells with micronuclei to every 2,000 cells scored, as a mutagenic parameter. The comet assay was used as a parameter for assessing the level of cell damage and the damage index. Since no significant changes in strain cells exposed to the aqueous extract in the comet and micronucleus assays were reported, it seems that no genotoxicity evidence is extant at the concentrations and in the assays performed.Em diversos lugares do mundo a utilização de plantas como fonte paliativa ou de cura para determinadas condições patológicas é bastante comum. No Brasil, essa prática não se torna diferente devido à ampla biodiversidade da fauna e flora presentes no País. Nesse contexto, surge a Xanthium spinosum (Asteraceae), conhecida popularmente como "espinho-de-carneiro", um arbusto anual introduzido na América do Sul, o qual tem sido utilizado empiricamente no tratamento de neoplasias. Sabendo do extensivo uso dessa planta em contrapartida com nenhum estudo reportando os reais efeitos de sua infusão, o objetivo do estudo foi avaliar a genotoxicidade do extrato aquoso nas concentrações de 0,02 g L-1, 0,1 g L-1 e 0,2 g L-1, através do ensaio do micronúcleo písceo e do ensaio cometa em leucócitos de sangue humano. O ensaio do micronúcleo tem como parâmetro mutagênico a presença de no mínimo 50 células com micronúcleo em uma contagem de 2.000 células por amostra, enquanto o ensaio cometa utiliza como parâmetro o nível de dano e o índice de dano. Os resultados mostram que não foi possível observar mudanças significativas nas células expostas ao extrato aquoso, em ambos os testes, o que sugere não existir evidência de genotoxicidade nas concentrações utilizadas no ensaio

Non-transferrin-bound iron in plasma or serum from patients with idiopathic hemochromatosis. Characterization by high performance liquid chromatography and nuclear magnetic resonance spectroscopy

The nature of non-transferrin-bound iron in the plasma or serum of iron-overloaded hemochromatosis patients was studied by high performance liquid chromatography (HPLC) and high resolution nuclear magnetic resonance (NMR). 500-MHz proton Hahn spin-echo NMR spectra of plasma or serum, combined with the use of the iron chelator desferrioxamine, suggests complexation of iron ions with citrate and a possible involvement of acetate. Addition of FeCl3 to hemochromatosis samples broadened the NMR signals from citrate. HPLC analysis rigorously confirmed the presence of an iron-citrate complex in ultrafiltrates of plasma or serum studies with added FeCl3 or desferrioxamine supported this conclusion. It is proposed that non-transferrin-bound iron in the plasma of iron-overloaded patients exists largely as complexes with citrate and possibly also as ternary iron-citrate-acetate complexes. The presence of such complexes would account for the ability of non-transferrin-bound iron to be measurable by the bleomycin assay and for its rapid clearance from the circulation by the liver

The effect of black tea on risk factors of cardiovascular disease in a normal population

OBJECTIVES:<br/> A prospective randomized controlled clinical trial determined the effect of Mauritian black tea consumption on fasting blood plasma levels of glucose, lipid profiles and antioxidant status in a normal population.<br/> METHODS:<br/> The study group (71%) consumed 3 x 200 ml of black tea infusate/day for 12 weeks without additives followed by a 3 week wash-out. The control group (29%) consumed equivalent volume of hot water for same intervention period.<br/> RESULTS:<br/> The tea used had high levels of gallic acid derivatives (50 ± 0.4 mg/L), flavan-3-ols (42 ± 2 mg/L), flavonols (32 ± 1 mg/L) and theaflavins (90 ± 1 mg/L). Daily 9 g supplementation of black tea infusate induced, in a normal population, a highly significant decrease of fasting serum glucose (18.4%; p<0.001) and triglyceride levels (35.8%; p<0.01), a significant decrease in LDL/HDL plasma cholesterol ratio (16.6%; p<0.05) and a non significant increase in HDL plasma cholesterol levels (20.3%), while a highly significant rise in plasma antioxidant propensity (FRAP: 418%; p<0.001) was noted . <br/>CONCLUSION:<br/> Black tea consumed within a normal diet contributes to a decrease of independent cardiovascular risk factors and improves the overall antioxidant status in humans

Effect of Hydroxytyrosol Found in Extra Virgin Olive Oil on Oxidative DNA Damage and on Low-Density Lipoprotein Oxidation

Journal of Agricultural and Food Chemistry46125181-5187JAFC

Black tea reduces uric acid and C-reactive protein levels in humans susceptible to cardiovascular diseases

The effect of black tea on the level of uric acid (UA) and C-reactive proteins (CRP) in humans susceptible to ischemic heart diseases was assessed in a prospective randomized controlled study. The study group consumed 9 g of black tea (equivalent to three cups of tea) daily for 12 weeks without additives followed by a 3-week wash-out (with control group consuming equivalent volume of hot water). Black tea consumption induced a highly significant decrease in the high uric acid baseline groups >6 mg/dL by 8.5%; p < 0.05. For men and women in the base line group >7 mg/dL, the decrease was 9.4% and 7.1%, respectively. In the low baseline serum uric acid levels there was a non-significant increase of 3.7% and 15% in men and women, respectively. C-reactive protein in the high risk group >3 mg/L was significantly decreased by 53.4% and 41.1% in men and women, respectively. For the non-supplemented group in this range the changes were 3.7% decrease for men and 2.9% increase for women. Tea supplementation-associated decrease in plasma uric acid and C-reactive protein levels may benefit humans at high risk of cardiovascular events and may augment drug therapy