[Analysis of tissue bioavailability of total polyphenols by Folin Ciocalteu and Fast Blue BB techniques in organs of BALB/C/c mice]. / Análisis de la biodisponibilidad tisular de polifenoles totales mediante las técnicas de Folin Ciocalteu y Fast Blue BB en órganos de ratones BALB/C.

Biomedical potential of polyphenols lies in their ability to modulate redox balance and the mechanisms involved in the development of chronic noncommunicable diseases. OBJECTIVE: The aim of this study was to determine the concentration of total polyphenols in different murine organs by assaying analytical techniques of Folin Ciocalteu (FC) and Fast Blue BB (FBBB). METHOD: Balb/c female mice (n≥3) received for 15 days 100 mg/kg/d of extract of Lantana grisebachii (LG), Aspidosperma quebracho-blanco (AQB) or Ilex paraguariensis (IP) and control group (treated with water without extract). Polyphenolic concentrations were measured in telencephalon, diencephalon, midbrain, brainstem, cerebellum, spleen, thymus and cardiopulmonary tissue by FC and FBBB methods. Results were compared by ANOVA followed by Tukey test (p<0.05). RESULTS: FBBB method reported higher detections than FC (4.5 fold in telencephalon, 8.4 in midbrain, 5 in brainstem, 7.2 in spleen, 68.5 in thymus and 4 in cardiopulmonary tissue). Regarding the treatments, the group that received AQB showed to have increased polyphenolic bioavailability in brainstem (p<0.02). With FBBB, a decrease on thymic polyphenol content after treatment with IP was detected (p<0.005). In cerebellum of the groups treated with IP and telencephalon of the control group showed significant differences when these were analyzed with FC (p<0.05, p<0.0035 respectively). CONCLUSIONS: FBBB method showed higher estimations of polyphenolic bioavailability than FC, and this could be related to higher specificity of the technique to react with phenolic compounds.

Effects of oral phytoextract intake on phenolic concentration and redox homeostasis in murine encephalic regions.

Vegetable infusions (VI) are one of the main phenolic sources for humans. They may act as antioxidants in the central nervous system, but data about their effect are insufficient. The main objective of the study was to determinate the effects of oral VI of Argentinean plants on phenolic concentration and redox homeostasis in different murine encephalic regions. Redox changes (peroxides -HP-, anion superoxide -SO- and γ-glutamyltranspeptidase activity) and tissue phenolics were assessed in Balb/c mice of both sexes treated with the following VI extracts: Lantana grisebachii Seckt. var. grisebachii (Verbenaceae) (LG), Aspidosperma quebracho-blanco Schltdl. (Apocynaceae) (AQB), and Ilex paraguariensis A. St.-Hil. (Aquifoliaceae) (IP). Brain (telencephalon and diencephalon), midbrain, brainstem, and cerebellum were studied (analysis of variance, P < 0.05). A redox homeostasis depending on an appropriate phenolic balance was detected after marker analysis. Under situations without exogenous challenges, the excessive or deficient levels were deleterious on each region. This finding was confirmed independently of the utilized phytoextracts. LG and AQB caused such phenolic imbalance and triggered oxidative stress. IP group showed region-specific differential redox effects. Overall, the last extract exhibited the best redox profile when the complete encephalon was analyzed. Since this plant has sanitary impact due to its high human intake, new studies about it are warranted.

In vivo redox effects of Aspidosperma quebracho-blanco Schltdl., Lantana grisebachii Stuck and Ilex paraguariensis A. St.-Hil. on blood, thymus and spleen of mice.

Argentinian native plants Aspidosperma quebracho-blanco, Lantana grisebachii and Ilex paraguariensis are known to have antiinflammatory and antioxidant properties. We demonstrated it in vivo by the redox changes in murine hemolymphatic tissues after infusive extract intake of these plants as revealed in organic trophism, tissue phenolics, hydroperoxides, superoxide, nitrites and gamma-glutamyltranspeptidase in thymus, blood and spleen. A. quebracho-blanco reduced hydroperoxidation in blood and spleen of both sexes, with gamma-glutamyltranspeptidase negativization in lymphatic organs and thymic nitrosative up-regulation. Males have shown increased phenolic content in blood after treatment. L. grisebachii and I. paraguariensis treatment exhibited incomplete antioxidation and oxidative induction in the studied tissues. Different results according to sex were found in redox response to phenolics and their kinetics, with males showing antioxidant effects, whereas females showed oxidative susceptibility. A. quebracho-blanco exhibited protection of murine tissues against oxidation in both sexes and modulation of their trophism, supporting its therapeutic uses in inflammatory diseases. Also, gender had significant influence in phenolic biodistribution and redox response.

Nutritional chemoprevention of urinary tract tumors (UTT) induced by lithogenic agents: risk for UTT in children exposed to melamine-contaminated milk formulas.

Urinary tract tumors are tenth in frequency, and many environmental carcinogens are excreted by urine. Interplay between chronic inflammatory urolithiasis and urothelial carcinogenesis is not well understood. Experimental evidences show that dietary melamine induce these events even at low concentrations. This is important because thousands of children were exposed to melamine through intentionally contaminated milk formula worldwide. We propose that an increased risk for urinary tumors in adult life may occur and screenings for early urinary signs may be necessary. Therefore, urothelial biology, melamine carcinogenic potential, and related epidemiology are discussed, recommending a preventive dietary polyunsaturated fatty acid-based supplementation, since they modulate such interplay in rodents.

Antioxidant activity of different extracts of Argentinian medicinal plants against arsenic-induced toxicity in renal cells.

Chronic toxicity of arsenic resulting from drinking water is a health problem encountered in humans, especially in South America and Asia, where a correlation between oxidative stress, tumor promotion, and arsenic exposure has been observed. Differential solvent extraction (petroleum ether (PE); dichloromethane (DCM); methanol (OL) and water (W)) was performed to compare the protective (antioxidant) activity of five Argentinian medicinal plants on arsenite-induced oxidative stress in Vero cells, assayed by hydroperoxide measurement. The results were analyzed using ANOVA followed by the LSD Fisher test. The data showed that arsenite was a pro-oxidant agent which acts in a time-dose-dependent manner. Extracts from Eupatorium buniifolium (PE), Lantana grisebachii (PE, W), Mandevilla pentlandiana (PE, W), and Sebastiania commersoniana (DCM, OL, W) prevented the formation of both aqueous and lipid hydroperoxides, but Heterothalamus alienus only impeded lipid ones. Therefore, antioxidant extracts are potentially beneficial and may have a protective activity against arsenite-induced renal injury. Among these, the aqueous extract of L. grisebachii may represent the most suitable preparation for humans since the traditional usage of this plant in popular medicine is through consumption of tea.