Toxicity evaluation of traditional and organic yerba mate (Ilex paraguariensis A. St.-Hil.) extracts.

Yerba mate (Ilex paraguariensis A. St.-Hil.) is an important source of biologically active compounds with pharmacological potential. The aim of this study was to examine the toxicity of different extracts obtained from either traditional or organic cultivated yerba mate in vitro and in vivo. Aqueous, ethanolic and methanolic extracts were obtained from commercial samples of yerba mate and total phenolic content was determined employing Folin-Ciocalteau reagent. The aqueous extracts presented higher content of total phenols, compared to ethanolic and methanolic extracts, and also demonstrated lower cytotoxicity, which is the basis for testing were carried out only using aqueous extracts. The main phenolic acids found in traditional aqueous (TA) extract were chlorogenic, gallic and protocatechuic acids. Gallic and hydroxybenzoic acids were detected in aqueous cultivated organic (OA) extract. Pretreatment with OA extract (100 µg/ml, 1 hr) was cytoprotective against rotenone-induced toxicity (1 µM). For in vivo toxicity assay, zebrafish embryos were exposed to OA or TA extracts (10-160 µg/ml) at 4 hr post fertilization. TA extract decreased embryos survival in a concentration-dependent manner, reduced the hatching rate at 40 µg/ml, increased edema frequency at 80 µg/ml and altered body curvature at 120 µg/ml. Further, TA extract produced locomotor disorders at concentrations equal to or greater than 10 µg/ml. In contrast, OA extract exhibited no apparent toxic effect on organogenesis and behavior up to 100 µg/ml. In summary, the OA cultivated extract showed the lowest cytotoxicity in vitro, enhanced reduction in rotenone-induced toxicity, and produced less toxicity in zebrafish embryos compared to the TA extract.

Polycyclic aromatic hydrocarbons as a potential source of carcinogenicity of mate.

Drinking mate, an infusion of the herb ilex paraguariensis, is very common in several South American countries, and has been associated with an increased risk of esophageal cancer. This increased risk may be attributed to drinking mate very hot, or to mate's potentially carcinogenic contaminants, such as polycyclic aromatic hydrocarbons (PAHs). Mate leaves are often dried via smoking, and therefore commercial samples may have high amounts of PAHs. We found 10 original articles that had measured PAHs in commercial dry samples, and nearly all found very high mass fractions. Most studies found benzo[a]pyrene mass fractions to be over 25 ng/g, and some found levels up to 600 ng/g. However, carcinogenic PAHs are often hydrophobic, and may not readily transfer into infusions. Seven articles studied transfer rates, and these rates varied from 1 to 50%, depending on the methods employed. Further careful studies of transfer rates in situations that mimic real life drinking of mate are recommended. Also, further studies of biological indicators of PAH exposure, particularly in randomized experiments, and analyzing DNA from tumor samples of mate drinkers are recommended.

Evaluation of Reproductive Toxicology of Aqueous Extract of Yerba Mate (Ilex paraguariensis A. St.-Hil.), a Traditional South American Beverage.

Yerba mate (Ilex paraguariensis A. St.-Hil.; Aquifoliaceae) is a popular tonic and stimulant beverage that is widely consumed in different South American countries. Estimates indicate the consumption of >1 L per day in southern Brazil and Uruguay. Despite its relatively high consumption, data on reproductive toxicity during critical periods of gestation remain unclear. Thus, we evaluated the effects of an aqueous extract of I. paraguariensis leaves ("chimarrão" [IPC]) at two critical periods of gestation in Wistar rats: preimplantation embryonic stage and fetal organogenesis. Pregnant Wistar rats were orally treated with IPC (3, 30, and 300 mg/kg) from days 1 to 7 or 8 to 21 of pregnancy. The respective control groups received vehicle. During treatment, clinical signs of maternal toxicity, maternal body weight, and food and water intake were monitored. The rats were killed on days 8 and 20 of pregnancy, and the following parameters were evaluated: weight of the maternal uterus, weight of the liver, weight of the kidneys, weight of the spleen, total embryo implantation, preimplantation loss, the mean of live fetuses, the percentage of dead fetuses, fetus weight, and fetal malformation. The aqueous extract of the leaves of I. paraguariensis L. did not present any deleterious effects on preimplantation embryos or the organogenesis of offspring from female Wistar rats. These safety data provide evidence that IPC may be safe for consumption during gestation.

Urinary Concentrations of Polycyclic Aromatic Hydrocarbon Metabolites in Maté Drinkers in Rio Grande do Sul, Brazil.

Background: Consumption of maté, an infusion of the herb Ilex paraguariensis (yerba maté), is associated with increased risk of esophageal squamous cell carcinoma (ESCC), but the carcinogenic mechanism is unclear. Commercial brands of yerba maté contain high levels of carcinogenic polycyclic aromatic hydrocarbons (PAHs), which are acquired during the traditional drying process. The purpose of this study was to characterize exposure to PAHs in maté drinkers over a wide range of maté consumption.Methods: We recruited 244 adults who answered a questionnaire and collected a fasting spot urine specimen. We quantified urinary concentrations of seven PAH metabolites and assessed associations between self-reported recent maté consumption and urinary PAH metabolites by multivariate regression.Results: Recent maté consumption showed a significant dose-response association with 6 of 7 PAH metabolites in unadjusted models (Ptrend < 0.05). After adjustment for creatinine and potential confounders, concentrations of 2-naphthol, 1-hydroxyphenanthrene, and the sum of 2- and 3-hydroxyphenanthrene remained significantly associated with recent maté intake. The sum of the urinary concentrations of the phenanthrene metabolites was similar or higher among maté drinkers who did not smoke than among smokers who did not drink matéConclusions: Urinary concentrations of PAH metabolites were significantly associated with self-reported amounts of recent maté intake, and drinking maté increased urinary concentrations of some PAH metabolites as much as smoking cigarettes.Impact: Drinking maté is a source of exposure to potentially carcinogenic PAHs, consistent with the hypothesis that the PAH content of maté may contribute to the increased risk of ESCC in maté drinkers. Cancer Epidemiol Biomarkers Prev; 27(3); 331-7. ©2017 AACR.

Effects of Yerba Mate (IIex paraguariensis) on Histomorphometry, Biomechanics, and Densitometry on Bones in the Rat.

Yerba mate (Ilex paraguariensis) is a xanthine-containing beverage, which is also rich in caffeine. Because caffeine has a negative impact on bone mineral density (BMD) mainly associated with low calcium (Ca) diets, there would be expected a negative effect of yerba mate on bone. In this study, Sprague-Dawley rats were used and randomly assigned into four groups (n = 6/group): Control + Ca 0.2 g %; Control + Ca 0.9 g %; Yerba + Ca 0.2 g %; Yerba + Ca 0.9 g %. At the end of the experiment, tibias and femurs were obtained for BMD, morphometric, histomorphometric, and biomechanical analyses. While there was no difference in bone parameters between rats with and without yerba mate consumption, a negative effect of low Ca diet was observed in BMD, morphometric, histomorphometric, and biomechanical results. Interaction between Ca content in the diet and yerba mate was only found in trabecular bone volume, which would indicate that the negative effect of low Ca intake on bone volume is reversed in part by yerba mate infusion. However, yerba mate was not able to reverse the negative effect of low Ca content on biomechanical properties and trabecular connectivity. In summary, at least in our study, yerba mate would not have a negative effect on bone and would be safe for the bone health of consumers.

The evaluation of maté (Ilex paraguariensis) genetic toxicity in human lymphocytes by the cytokinesis-block in the micronucleus assay.

The present study evaluates the clastogenic and/or aneugenic potential of maté (Ilex paraguariensis) - previously tested for the presence of 48 organophosphorous pesticides - in the culture of human lymphocytes in the absence of exogenous metabolic activation. Peripheral blood was obtained once from three healthy female donors for lymphocyte cell cultures. The cultures were treated with maté infusion (filtered in sterilized sartorius filter with a 0.22 mm pore membrane), distilled water (negative control), and 6 microg/ml bleomycin (positive control). For each experimental person, 3000 binucleated cells (BN) from two independent cultures (1000 cells from replicate cultures) were scored for the presence of micronuclei (MN). No statistical differences between maté infusion concentrations were observed: 1400 microg/ml (0.001+/-0.002), 700 microg/ml (0.0006+/-0.0015), 350 microg/ml (0.002+/-0.002), 175 microg/ml (0.002+/-0.003) and negative control (0.001+/-0.001). The present findings show that there is no clastogenic or/and aneugenic basis underlying maté action in the CBMN assay.

Survey of natural radioactivity levels in Ilex paraguariensis (St. Hil.) by gamma-ray spectrometry

The mate tea (Ilex paraguariensis - St. Hil.) is a beverage broadly cultivated and consumed in Brazil. The radioactive traces present in three trademarks of toasted mate tea produced at the south of Brazil were analyzed. Measurements were carried out by gamma-ray spectrometry. The average value for the 40K activity measured for marks A, B and C was 1216 ± 8, 1047 ± 14 and 666 ± 13 Bq.kg-1, respectively. The 137Cs activity was lower than the limit of detection.

Uma bebida amplamente consumida e cultivada no Brasil é o chá-mate (Ilex paraguariensis - St. Hil). Foram analisados os traços radioativos de três marcas comerciais de chá-mate tostado produzidos no sul do Brasil. As medidas foram realizadas por espectrometria gama. Os valores médios para as atividades medidas do 40K, para as marcas A, B e C foram 1216 ± 8, 1047 ± 14 e 666 ± 13 Bq.kg-1, respectivamente. As atividades para o 137Cs foram menores que o limite mínimo de detecção.