Stability of Leaf Yerba Mate (Ilex paraguariensis) Metabolite Concentrations over the Time from the Prism of Secondary Sexual Dimorphism

The yerba mate leaf metabolic composition depends mainly on genetics, sex, plant and leaf age, light intensity, harvest time, climate, and fertilization. In yerba mate, the secondary sexual dimorphism (SSD), the leaf metabolic SSD association with the frequency of leaf harvests, and the stability of the metabolites in the two genders over the years is not known. It was hypothesized that (1) the SSD in the metabolite segregation would differ among the winter and summer growth pauses, (2) females would show lower metabolite concentrations, and (3) the metabolic concentrations would show stability over the years on the same plants, not obligatorily associated with the SSD stability expression. Variations in theobromine, caffeine, chlorogenic and caffeic acids were correlated to the increasing time since the previous harvest, especially in females. However, the frequency of the metabolic SSD were associated with the studied growth pauses, rejecting the first hypothesis. No regular gender superiority was expressed in the yerba mate leaf secondary metabolites, rejecting our second hypothesis, even though more cases of superior female metabolite accumulation were identified. The stability of the leaf protein was preserved over the four years, with no SSD cases observed. The leaf methylxanthines were time stable, while the decrease in the phenolic content occurred with tree aging, which was not associated with the SSD expression, partially proving our third hypothesis. The novelty was related to the time stability of the leaf metabolic SSD observed over the winter and summer growth pauses, and over the four consecutive years without a regular expression of the male- or female-biased concentrations in the studied metabolites. To demystify the random metabolic gender responses in yerba mate, gender-orientated experiments with a high number of tree repetitions must be conducted, including clonal plants grown in various environments, such as monoculture and agroforestry, or on plantations in different climates and altitudes.

Multigenomic modifications in human circulating immune cells in response to consumption of polyphenol rich extract of yerba mate (Ilex paraguariensis A. St.-Hil.) are suggestive of cardiometabolic protective effects

Mate is a traditional drink obtained from the leaves of yerba mate and rich in a diversity of plant bioactive compounds including polyphenols, particularly chlorogenic acids. Studies, even though limited, suggest that consumption of mate is associated with health effects, including prevention of cardiometabolic disorders. Molecular mechanisms underlying the potential health properties are still largely unknown, especially in humans. The aim of this study was to investigate nutrigenomic effects of mate consumption and identify regulatory networks potentially mediating cardiometabolic health benefits. Healthy middle-aged men at risk for cardiovascular disease consumed a standardized mate extract or placebo for 4 weeks. Global gene expression, including protein coding and non-coding RNAs profiles were determined using microarrays. Biological function analyses were performed using integrated bioinformatic tools. Comparison of global gene expression profiles showed significant change following mate consumption with 2635 significantly differentially expressed genes, among which 6 are miRNAs and 244 are lncRNAs. Functional analyses showed that these genes are involved in regulation of cell interactions and motility, inflammation or cell signaling. Transcription factors, such as MEF2A, MYB or HNF1A, could have their activity modulated by mate consumption either by direct interaction with polyphenol metabolites or by interactions of metabolites with cell signaling proteins, like p38 or ERK1/2, that could modulate transcription factor activity and regulate expression of genes observed. Correlation analysis suggests that expression profile is inversely associated with gene expression profiles of patients with cardiometabolic disorders. Therefore, mate consumption may exert cardiometabolic protective effects by modulating gene expression towards a protective profile.

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.

90-Day Oral Toxicity Assessment of Tropaeolum majus L. in Rodents and Lagomorphs

Tropaeolum majus L., popularly known as nasturtium, is a species widely used in the form of infusions and salads. In the last years, the antihypertensive, diuretic, and calcium and potassium sparing activities of T. majus preparations were shown. Moreover, no preclinical 90-day oral toxicity studies were conducted. Thus, this study evaluated the toxicity of the hydroethanolic extract obtained from T. majus (HETM) leaves in female and male mice, rats, and rabbits. Swiss mice and Wistar rats were treated with HETM (75, 375, and 750 mg/kg). The doses of rabbits (30, 150, and 300 mg/kg) were calculated by allometric extrapolation. The control groups received vehicle. The animals were orally treated, daily, for 90 days. At the end, the animals were anesthetized, and body weight gain, relative weight of liver, kidney, and spleen, and histopathological changes were evaluated. Serum hematological and biochemical parameters were also analyzed. No alterations were found in body and organ weights or in histopathological and biochemical evaluation. Hematological analyses revealed small changes in lymphocytes and neutrophil counts in rats after administration of 750 mg/kg of HETM. These results showed that 90-day use of T. majus is safe in rodents and lagomorphs.

Mechanisms underlying antiatherosclerotic properties of an enriched fraction obtained from Ilex paraguariensis A. St.-Hil

BACKGROUND

Ilex paraguariensis A. St. Hil. var. paraguariensis (Aquifoliaceae) popularly known as 'mate' is an important species native to South America. Despite numerous studies showing significant antioxidant and lipid lowering properties, the antiatherosclerotic mechanisms of this species remain unknown.

PURPOSE

To evaluate the possible antiatherosclerotic effects of a butanolic fraction (n-BFIP) obtained from I. paraguariensis and to investigate the molecular mechanisms involved in this activity.

METHODS

First, n-BFIP was obtained from the hydroalcoholic extract and a detailed phytochemical investigation about its main secondary metabolites was performed. Then, during 8 experimental weeks, rabbits received diet supplemented with 1% cholesterol (CRD). After 4 weeks of CDR, animals were redistributed into five groups (n = 6) and treated (p.o.) with n-BFIP (10, 30 and 100 mg/kg), simvastatin (5 mg/kg), or vehicle (filtered water, 1 ml/kg) once daily for 4 weeks. An additional group was fed with cholesterol-free diet and treated with vehicle. At the end of 8 weeks, serum samples were obtained for the measurement of serum lipids, lipid and protein oxidation and indirect nitric oxide levels. In addition, serum IL-1β, IL-6, sICAM-1, sVCAM-1, and intracellular cGMP levels in rabbit aortic rings were measured. Samples from the aortic arch and thoracic segment were collected for histopathological analysis.

RESULTS

CRD induced oxidative and nitrosative stress and increased serum lipids, IL-1β, IL-6, sICAM-1, and sVCAM-1 levels. In addition, structural changes in the intima layers of different arterial branches were also found. Although it did not change serum lipids, n-BFIP reverted oxidative and nitrosative stress and reduced IL-1β, IL-6, sICAM-1, and sVCAM-1 levels, besides to increasing intracellular levels of cGMP in vitro. In addition, the formation of atherosclerotic plaques was reduced to values close to those of animals fed with cholesterol-free diet.

CONCLUSIONS

A 4-week n-FBIP treatment reduces the progression of the atherosclerotic disease in New Zealand rabbits. These effects are associated with an attenuation of oxidative and nitrosative stress, affecting IL-1β, IL-6, sICAM-1 and sVCAM-1 levels.

Genetic and Phytochemical Analysis to Evaluate the Diversity and Relationships of Mate (Ilex paraguariensis A.St.-Hil.) Elite Genetic Resources in a Germplasm Collection

The aim of this study was to evaluate the phytochemical and genetic diversity, relationships and identification of mate (Ilex paraguariensis A.St.-Hil.) elite genetic resources belonging to the Brazilian germplasm collection and mate breeding program. Mate has been studied due to the presence of phytochemical compounds, especially methylxanthines and phenolic compounds. The samples were collected from the leaves of 76 mate elite genetic resources (16 progenies × 5 localities). Total DNA was extracted from mate leaves and 20 random primers were used for DNA amplification. Methylxanthines (caffeine and theobromine) and phenolic compounds (chlorogenic, neochlorogenic, and criptochlorogenic acids) were quantified by HPLC. The genetic divergence estimated was higher within (92%) than among (8%) the different populations. Analysis of genetic distance between origins provided the formation of two groups by UPGMA cluster analysis, with higher polymorphism (94.9%). The average content of caffeine ranged from 0.01 to 1.38% and theobromine of 0.10 - 0.85% (w/w). The caffeoylquinic acids concentrations (1.43 - 5.38%) showed a gradient 3-CQA > 5-CQA > 4-CQA. The coefficient of genetic variation (CVg) was of low magnitude for all mono-caffeoylquinics acids. Significant correlations (positive and negative) were observed between the phytochemical compounds. Genetic diversity analysis performed by RAPD markers showed a greater intra-populational diversity; genetic resources with low caffeine and higher theobromine content were identified and can be used in breeding programs; the correlation between methylxanthines and phenolic compounds can be used as a good predictor in future studies.

Ethno-medicinal study of plants used for treatment of human ailments, with residents of the surrounding region of forest fragments of Paraná, Brazil

ETHNOPHARMACOLOGICAL RELEVANCE

This study aims to document the traditional knowledge on the use of medicinal plants in the neighborhood of the protected area "Parque Estadual da Cabeça do Cachorro", a fragment of seasonal semideciduous forests. This vegetation is intensely fragmented and disturbed; despite its importance there are few records of the traditional knowledge of medicinal species.

MATERIAL AND METHODS

Twenty-four residents in the neighborhood of the protected area "Parque Estadual da Cabeça do Cachorro" were interviewed. The residents were questioned about preparation techniques, recommended doses, ways of administration and healing properties of various parts of the plants and were invited to walk through the park to collect in situ some species of plants. The recognized medicinal species were identified and traditional knowledge was systematized. Quantitative indices (Informant Consensus Factor - FIC and Use Value - UV) were calculated.

RESULTS

115 species of medicinal plants belonging to 54 botanical families were cited. Asteraceae (n=14), Fabaceae (n=11), Myrtaceae (n=6), Bignoniaceae, Solanaceae and Verbenaceae (n=5) were the most species-rich. The highest use values were calculated for Achyrocline satureioides, Aristolochia triangularis and Bauhinia forficata (0.63). Moreover, the informants consensus about usages of medicinal plants ranges from 0.024 to 0.663, which shows high level of agreements among the informants for gastro-intestinal and respiratory system diseases. Furthermore, for the first time, new traditional medicinal uses of Asteraceae (Chromolaena pedunculosa Hook. & Arn.), Commelinaceae (Tradescantia fluminensis Vell.) and Polypodiaceae (Microgramma vacciniifolia Langsd. & Fisch.) species were reported.

CONCLUSIONS

Present study revealed that the residents of the surrounding region of forest fragments of Paraná are rich in ethno-medicinal knowledge and rely on plant-based remedies for common health problems. As in many parts of Brazil knowledge of the past is combined with new knowledge that has recently been incorporated emphasizing the cultural changes that this area is experiencing. Despite the use of different species of plants are crucial to their way of life, there is concern that these rich popular knowledge may disappear in the future as a result of a possible modernization of this area.

Cardiovascular protective effects of Casearia sylvestris Swartz in Swiss and C57BL/6 LDLr-null mice undergoing high fat diet

ETHNOPHARMACOLOGICAL RELEVANCE

Although Casearia sylvestris Swartz is used in Brazilian folk medicine to treat obesity, no study has been conducted to evaluate the effects of this species in an experimental model of dyslipidemia and atherosclerosis. So, the aim of this study was to evaluate possible hypolipemiant and antiatherogenic activity of the methanolic extract obtained from Casearia sylvestris (MECS) using Swiss and C57BL/6 LDLr-null mice undergoing high fat diet (HFD).

MATERIAL AND METHODS

Dyslipidemia and atherogenesis were induced by the administration of commercial HFD for 4 weeks. The MECS was administered orally at doses of 250 and 500mg/kg, once a day, for two weeks, starting from the 2nd week of HFD. The gain in body weight and systolic blood pressure (SBP) were measured weekly over the four week study. At the end of the experiments the levels of triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and very low-density lipoprotein cholesterol (VLDL-C) were measured by colorimetric method. Aldosterone, vasopressin and angiotensin converting enzyme (ACE) activity were also evaluated in collected serum. The renal function, atherogenic index serum (AIS) and in vitro antiplatelet activity were investigated. Additionally, histopathological analyzes were performed to determine the intima-media thickness (IMT) and intima media ratio (IMR) in aorta samples.

RESULTS

The HFD induced dyslipidemia and major structural changes in the aortic wall, including raising of the systolic blood pressure in LDLr-null mice. In addition, we observed an increase in lipid peroxidation accompanied by a reduction of serum nitrite. The treatment with MECS was able to prevent the increase of SBP, TC, LDL-C, VLDL-C and triglycerides levels and increase HDL-C in Swiss and LDLr-null mice. These effects were accompanied by a significant reduction in oxidative stress. Moreover, AIS, IMT and IMR were significantly reduced in MECS-treated mice, and the extract was able to reduce platelet aggregation in vitro.

CONCLUSION

This study demonstrated that MECS reduces the serum lipids and oxidative stress when orally administered to Swiss and LDLr-null mice. In addition, it was able to prevent arterial thickening induced by HFD and to inhibit platelet aggregation in vitro.