Chemical profile and toxicogenetic safety assessment of Smallanthus sonchifolius (yacon) organic extracts.

The interest in Smallanthus sonchifolius (yacon) has strongly resurfaced due to its multiple beneficial effects on human health. This study aimed at determining the toxicity and the chemical profile of an ethanol extract (EE) and a crude lactone mixture (CLM) of yacon leaves. Cytotoxicity and genotoxicity tests were performed by the MTT assay and the alkaline version of the comet assay respectively. The phytochemical analysis, performed by chromatographic and spectroscopy techniques, revealed the presence of nine sesquiterpene lactones (STLs) and two acyclic diterpene acids. In all cases, cell viability was inversely proportional to the extract concentration employed. The effects obtained with the highest dose of EE were significantly different from those obtained with the negative and solvent controls. Conversely, no significant differences were observed between the lowest doses of EE and controls. As for CLM, all tested doses showed statistically significant increases, as compared to negative and solvent controls.

Toxicogenetic evaluation of Smallanthus sonchifolius (yacon) as a herbal medicine.

ETHNOPHARMACOLOGICAL RELEVANCE: Smallanthus sonchifolius (Poepp. & Endl.) H. Robinson, commonly known as yacon, is a medicinal plant belonging to the Asteraceae family used in traditional folk medicine. Its roots and leaves have been used by people suffering from diabetes or from various digestive or renal disorders. AIM OF THE STUDY: This study aimed at evaluating the in vitro potential genotoxic effects of the aqueous extract of yacon in order to determine its safety and at characterizing its phytochemical composition. MATERIALS AND METHODS: The aqueous extract of S. sonchifolius was prepared in a similar way to that commonly used in popular medicine as tea bags. Thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC-MS/MS) were used to identify the main compounds. The MTT test was performed to determine the range of doses and the Cytochalasine B-blocked micronucleus (Cytome assay) was used to assess geneotoxicity. RESULTS: The chemical analysis of the aqueous extract revealed the presence of the sesquiterpene lactones (STLs) enhydrin and the dimer enhydrofolin, as the main compounds together with phenolic compounds. Increasing concentrations of the extract induced a cytotoxic effect on CHO-K1 and HepG2 cells. A statistically significant increase in the frequency of MNi, NBUDs and NPBs was observed in CHO-K1 cells, while in HepG2 cells a statistically significant frequency increase was observed with three of the four tested doses for MNi and only with the highest dose for NPBs and NBUs (genotoxic effect). CONCLUSION: Results demonstrated the inability of the metabolic system to counteract the genetic instability, allowing the safe consumption of the leaves as a 2% tea infusion in quantities of up to 250 mL/day.

Modulation of hepatic ABC transporters by Eruca vesicaria intake: Potential diet-drug interactions.

The aim of this work was to evaluate whether oral administration of Eruca vesicaria, a species of rocket cultivated in Argentina, could modify cyclophosphamide (CP)-induced genotoxicity through modulation of hepatic ABC transporters. Daily oral administration of E. vesicaria fresh leaves juice (1.0, 1.4 and 2.0  g/kg) for 14 days did not alter genotoxicity biomarkers -alkaline comet assay and micronucleus test -in neither male nor female mice. Instead, repeated intake of this cruciferous decreased CP-induced DNA damage dose-dependently and it caused hepatic overexpression of P-glycoprotein (P-gp; 1.4 and 2.0  g/kg) and multidrug resistance protein 2 (MRP2; 2.0  g/kg), but not breast cancer resistance protein (Bcrp). The antigenotoxic effect of E. vesicaria was prevented by 50 mg/kg verapamil (P-gp inhibitor) or 10 mg/kg indomethacin (MRP2 inhibitor). In turn, CP-induced cytotoxicity (10 mM, 24 h) on human hepatoma cells (HepG2/C3A) was significantly reduced by preincubation with E. vesicaria (1.4 mg/ml; 48 h); this effect was absent when CP was coincubated with 35 µM verapamil, 80 µM indomethacin or 10 µM KO-143 (BCRP inhibitor). Altogether, these results allow us to demonstrate that repeated intake of E. vesicaria exhibited antigenotoxicity, at least in part, by induction of hepatic ABC transporters in vivo in mice as well as in vitro in human liver cells. This could account for other diet-drug interactions.

In vivo antigenotoxic activity of Diplotaxis tenuifolia against cyclophosphamide-induced DNA damage: Relevance of modulation of hepatic ABC efflux transporters.

Several epidemiological studies have demonstrated that a diet with high contents of cruciferous vegetables (which belong to the Brassicaceae family) may reduce the incidence of cancer and neurodegenerative diseases. However, some authors have postulated that they might bring about toxic effects. Therefore, the aim of this study was to assess the effects of chronic administration of Diplotaxis tenuifolia (wild rocket), a species found in Argentina, concerning its putative genotoxicity or antigenotoxicity against the DNA damage inducer cyclophosphamide, and its ability to modulate the hepatic expression of ABC efflux transporters on mice. The alkaline comet assay and the micronucleus test were used as genotoxicity biomarkers, and the ABC transporter expression was analyzed by Western-blotting. D. tenuifolia juice exhibited no genotoxicity in any of the three tested doses (p > 0.05), showing instead a protective effect against genotoxic damage induced by cyclophosphamide (p < 0.001) in a dose-dependent behavior. Furthermore, hepatic expression of ABCB1 remained unchanged in both sexes at every dose, whereas ABCG2 expression increased in females (p < 0.05) and males (p < 0.01) at the highest dose. Regarding ABCC2, sex-related differences were observed (p < 0.05), its expression decreasing in females (p < 0.05) and increasing in males (p < 0.05). The modulation of these transporters may contribute to the antigenotoxic effects of D. tenuifolia since they act as universal detoxifiers, excreting xenobiotics to the cellular exterior. Phytochemicals present in the juice such as glucosinolates, quercetin and kaempherol may be responsible for these beneficial effects.

Modulator effect of watercress against cyclophosphamide-induced oxidative stress in mice.

Watercress (Nasturtium officinale, Cruciferae; W. Aiton) is a vegetable widely consumed in our country, with nutritional and potentially chemopreventive properties. Previous reports from our laboratory demonstrated the protective effect of watercress juice against DNA damage induced by cyclophosphamide in vivo. In this study, we evaluated the in vivo effect of cress plant on the oxidative stress in mice. Animals were treated by gavage with different doses of watercress juice (0.5 and 1g/kg body weight) for 15 consecutive days before intraperitoneal injection of cyclophosphamide (100 mg/kg body weight). After 24 h, mice were killed by cervical dislocation. The effect of watercress was investigated by assessing the following oxidative stress biomarkers: catalase activity, superoxide dismutase activity, lipid peroxidation, and glutathione balance. Intake of watercress prior to cyclophosphamide administration enhanced superoxide dismutase activity in erythrocytes with no effect on catalase activity. In bone marrow and liver tissues, watercress juice counteracted the effect of cyclophosphamide. Glutathione balance rose by watercress supplementation and lipid oxidation diminished in all matrixes when compared to the respective control groups. Our results support the role of watercress as a diet component with promising properties to be used as health promoter or protective agent against oxidative damage.

Modulator effect of watercress against cyclophosphamide-induced oxidative stress in mice

Watercress (Nasturtium officinale, Cruciferae; W. Aiton) is a vegetable widely consumed in our country, with nutritional and potentially chemopreventive properties. Previous reports from our laboratory demonstrated the protective effect of watercress juice against DNA damage induced by cyclophosphamide in vivo. In this study, we evaluated the in vivo effect of cress plant on the oxidative stress in mice. Animals were treated by gavage with different doses of watercress juice (0.5 and 1g/kg body weight) for 15 consecutive days before intraperitoneal injection of cyclophosphamide (100 mg/kg body weight). After 24 h, mice were killed by cervical dislocation. The effect of watercress was investigated by assessing the following oxidative stress biomarkers: catalase activity, superoxide dismutase activity, lipid peroxidation, and glutathione balance. Intake of watercress prior to cyclophosphamide administration enhanced superoxide dismutase activity in erythrocytes with no effect on catalase activity. In bone marrow and liver tissues, watercress juice counteracted the effect of cyclophosphamide. Glutathione balance rose by watercress supplementation and lipid oxidation diminished in all matrixes when compared to the respective control groups. Our results support the role of watercress as a diet component with promising properties to be used as health promoter or protective agent against oxidative damage.

El berro (Nasturtium officinale, crucíferas; W. Aiton) es una hortaliza ampliamente consumida en nuestro país, con valor nutricional y propiedades potencialmente quimiopreventivas. En trabajos previos demostramos que el jugo de berro tiene efecto protector in vivo contra el daño del ADN inducido por ciclofosfamida en tejidos del ratón. En el presente trabajo evaluamos, también in vivo, los efectos del jugo sobre el estrés oxidativo en diferentes tejidos del ratón. Los siguientes biomarcadores fueron investigados: actividad de superóxido dismutasa, actividad de catalasa, peroxidación lipídica y balance de glutatión. Los animales fueron tratados con diferentes dosis de jugo (0.5 y 1 g/kg de peso corporal) por alimentación forzada durante 15 días consecutivos antes de la inyección intraperitoneal con ciclofosfamida (100 mg/kg). La ingesta de berro antes de la administración de ciclofosfamida mejoró la actividad de superóxido dismutasa en los eritrocitos sin efecto sobre la actividad de la catalasa. En médula ósea e hígado, el jugo de berro contrarrestó el efecto deletéreo de la ciclofosfamida. En todas las matrices, el balance de glutatión fue mayor y la oxidación de lípidos menor que los valores encontrados en los grupos control. Nuestros resultados demuestran que el berro es un componente de la dieta con propiedades prometedoras como promotor de la salud o como agente protector contra el daño oxidativo.

Isolation of acetylated bile acids from the sponge Siphonochalina fortis and DNA damage evaluation by the comet assay.

From the organic extracts of the sponge Siphonochalina fortis, collected at Bahía Bustamante, Chubut, Argentina, three major compounds were isolated and identified as deoxycholic acid 3, 12-diacetate (1), cholic acid 3, 7, 12-triacetate (2) and cholic acid, 3, 7, 12-triacetate. (3). This is the first report of acetylated bile acids in sponges and the first isolation of compound 3 as a natural product. The potential induction of DNA lesions by the isolated compounds was investigated using the comet assay in lymphocytes of human peripheral blood as in vitro model. The results showed that the administration of the bile acid derivatives would not induce DNA damages, indicating that acetylated bile acids are nontoxic metabolites at the tested concentrations. Since the free bile acids were not detected, it is unlikely that the acetylated compounds may be part of the sponge cells detoxification mechanisms. These results may suggest a possible role of acetylated bile acids as a chemical defense mechanism, product of a symbiotic relationship with microorganisms, which would explain their seasonal and geographical variation, and their influence on the previously observed genotoxicity of the organic extract of S. fortis.

Nutritional status of school-aged children and its relation to blood pressure.

INTRODUCTION: Obesity is associated with a wide range of cardiovascular and metabolic diseases. OBJECTIVE: To establish an association between the nutritional status of 6-10 year old boys and girls and blood pressure. POPULATION AND METHODS: A cross-sectional, analytical study was conducted in 6-10 year old schoolboys and schoolgirls. Outcome measures and indicators studied included nutritional status as per body mass index; presence of central fat mass distribution estimated by waist circumference; and blood pressure (height, age and gender tables). Differences in mean values were analyzed using a Student's t test. The relationship between outcome measures was estimated using Pearson's correlation coefficient. Linear regression models were adjusted for systolic blood pressure and diastolic blood pressure using the following explanatory outcome measures: z scores for body mass index, age, gender and waist circumference. RESULTS: Five hundred and fifty five male and female children were evaluated; they were all younger than 11 years old. A total of 26.3% was overweight and 15.1% was obese. The prevalence of hypertension was 1.08%. Results show a positive linear relationship between systolic and diastolic blood pressure, and age and waist circumference, and a trend is observed between systolic blood pressure and the body mass index z score (p = 0.068). CONCLUSION: Overweight and obesity were the most common nutritional disorders in schoolaged children in the studied district; there is an association between age, waist circumference, and systolic and diastolic blood pressure, and between systolic blood pressure and the body mass index z score.

Nutritional status of school-aged children and its relation to blood pressure / El estado nutricional de niños escolares y su relación con la tensión arterial

Introduction. Obesity is associated with a wide range of cardiovascular and metabolic diseases. Objective. To establish an association between the nutritional status of 6-10 year old boys and girls and blood pressure. Population and Methods. A cross-sectional, analytical study was conducted in 6-10 year old schoolboys and schoolgirls. Outcome measures and indicators studied included nutritional status as per body mass index; presence of central fat mass distribution estimated by waist circumference; and blood pressure (height, age and gender tables). Differences in mean values were analyzed using a Student's t test. The relationship between outcome measures was estimated using Pearson's correlation coefficient. Linear regression models were adjusted for systolic blood pressure and diastolic blood pressure using the following explanatory outcome measures: z scores for body mass index, age, gender and waist circumference. Results: Five hundred and fifty five male and female children were evaluated; they were all younger than 11 years old. A total of 26.3% was overweight and 15.1% was obese. The prevalence of hypertension was 1.08%. Results show a positive linear relationship between systolic and diastolic blood pressure, and age and waist circumference, and a trend is observed between systolic blood pressure and the body mass index z score (p= 0.068). Conclusion. Overweight and obesity were the most common nutritional disorders in schoolaged children in the studied district; there is an association between age, waist circumference, and systolic and diastolic blood pressure, and between systolic blood pressure and the body mass index z score.

Nutritional status of school-aged children and its relation to blood pressure / El estado nutricional de niños escolares y su relación con la tensión arterial

Introduction. Obesity is associated with a wide range of cardiovascular and metabolic diseases. Objective. To establish an association between the nutritional status of 6-10 year old boys and girls and blood pressure. Population and Methods. A cross-sectional, analytical study was conducted in 6-10 year old schoolboys and schoolgirls. Outcome measures and indicators studied included nutritional status as per body mass index; presence of central fat mass distribution estimated by waist circumference; and blood pressure (height, age and gender tables). Differences in mean values were analyzed using a Students t test. The relationship between outcome measures was estimated using Pearsons correlation coefficient. Linear regression models were adjusted for systolic blood pressure and diastolic blood pressure using the following explanatory outcome measures: z scores for body mass index, age, gender and waist circumference. Results: Five hundred and fifty five male and female children were evaluated; they were all younger than 11 years old. A total of 26.3% was overweight and 15.1% was obese. The prevalence of hypertension was 1.08%. Results show a positive linear relationship between systolic and diastolic blood pressure, and age and waist circumference, and a trend is observed between systolic blood pressure and the body mass index z score (p= 0.068). Conclusion. Overweight and obesity were the most common nutritional disorders in schoolaged children in the studied district; there is an association between age, waist circumference, and systolic and diastolic blood pressure, and between systolic blood pressure and the body mass index z score.(AU)

In vivo antigenotoxic activity of watercress juice (Nasturtium officinale) against induced DNA damage.

The present study was carried out to investigate the genotoxicity as well as possible protective activity against damage induced by cyclophosphamide (CP) of the aqueous juice of watercress (Nasturtium officinale, W.T. Aiton) in vivo. Male and female Swiss mice 7-8 weeks old (N = 48) were treated by gavage with 1 g kg(-1) body weight and 0.5 g kg(-1) body weight of watercress juice during 15 consecutive days. Genotoxicity and its possible protective effect were tested by the comet assay in peripheral blood cells and the micronucleus test in bone marrow. In addition, biopsies of the bladder, epididymis and testicles of mice were performed to extend the experimental design. Watercress juice per se did not induce genetic damage according to the comet assay and micronucleus study, exhibiting a protective activity against CP (P < 0.05 and P < 0.001, respectively). The comparative analysis of bladder histological changes obtained in the watercress plus CP group against those treated with CP alone suggests a probable protective effect. Further studies are needed in order to establish the protective role of watercress juice against DNA damage.

Nutritional status of school-aged children and its relation to blood pressure. / Nutritional status of school-aged children and its relation to blood pressure.

INTRODUCTION: Obesity is associated with a wide range of cardiovascular and metabolic diseases. OBJECTIVE: To establish an association between the nutritional status of 6-10 year old boys and girls and blood pressure. POPULATION AND METHODS: A cross-sectional, analytical study was conducted in 6-10 year old schoolboys and schoolgirls. Outcome measures and indicators studied included nutritional status as per body mass index; presence of central fat mass distribution estimated by waist circumference; and blood pressure (height, age and gender tables). Differences in mean values were analyzed using a Students t test. The relationship between outcome measures was estimated using Pearsons correlation coefficient. Linear regression models were adjusted for systolic blood pressure and diastolic blood pressure using the following explanatory outcome measures: z scores for body mass index, age, gender and waist circumference. RESULTS: Five hundred and fifty five male and female children were evaluated; they were all younger than 11 years old. A total of 26.3

was overweight and 15.1

was obese. The prevalence of hypertension was 1.08

. Results show a positive linear relationship between systolic and diastolic blood pressure, and age and waist circumference, and a trend is observed between systolic blood pressure and the body mass index z score (p = 0.068). CONCLUSION: Overweight and obesity were the most common nutritional disorders in schoolaged children in the studied district; there is an association between age, waist circumference, and systolic and diastolic blood pressure, and between systolic blood pressure and the body mass index z score.

Aqueous extracts of Lippia turbinata and Aloysia citriodora (Verbenaceae): assessment of antioxidant capacity and DNA damage.

The aim of the present work was to make a contribution to the knowledge of aqueous extracts of Lippia turbinata and Aloysia citriodora (Verbenaceae; infusion and decoction) in relation with the establishment of its antioxidant activity and lack of DNA damage, for its potential use in therapeutics. The cytogenotoxic profile was evaluated through genotoxic biomarkers such as mitotic index, cellular proliferation kinetics, sister chromatid exchanges, single-cell gel electrophoresis assay, and micronucleus test in human peripheral blood lymphocyte cultures. No statistical differences were found (P > .05) between control and exposed cultures, even between both aqueous extracts. The total antioxidant capacity was shown to be higher in the decoction than in the infusion and both aqueous extracts protected against protein carbonylation and lipid peroxidation, the decoction being more efficient than the infusion (P < .005). These results suggest the safe use of these medicinal plants as chemoecologic agents in therapeutics.

Antigenotoxic activity of watercress extract in an in vitro mammalian system using comet assay.

Watercress (Cruciferae), an integral part of Mediterranean diets, is a nutritive food which is used in the treatment of several diseases. Oxidative DNA damage seems to play a crucial role in chronic, aging-related diseases and it is considered an important and probably carcinogenic factor. The aim of this work was to determine the impact of watercress extract on cell viability and its potential antigenotoxic properties against induced oxidative damage, using a comet assay and peripheral blood cells as an in vitro model. An aqueous extract of the leaves was prepared using a juice processor, centrifuged, filtered and preserved at -20 °C. Two concentrations of the aqueous extract (13.2 and 26.4 mg/mL) were assayed. No differences were found in cell viability between the control and treated groups at any time. Significant antigenotoxic effects were observed for both concentrations, expressed as the damage index (p = 0.005 at 30 min; p < 0.001 at 60 and 90 min), the percentage reductions in damage being similar between them (67.1-75.2% respectively). These results suggest that the consumption watercress in the diet is a powerful tool for improving health and the quality of life.

[Biochemical evaluation on rural workers exposed to pesticides]. / Evaluación bioquímica de trabajadores rurales expuestos a pesticidas.

Pesticides are used in agriculture to protect crops but may represent a potential risk to farmers and the environment. The aim of this work was to evaluate horticultural workers exposed to pesticide, categorized by: direct exposure (n = 45), indirect exposure (n = 50) and controls (n = 50) using exposure and effect biomarkers: cholinesterase (ChE), acetylcholinesterase (AChE), catalase (CAT), lipid peroxidation (TBARS), Damage Index Comet Assay (IDEC) and Damage Index Repair Assay (IDER). Our results show: a) an AChE inhibition in directly and indirectly exposed population (p < 0.001), b) significant increase in the levels of TBARS in direct exposure (p < 0.001), c) the CAT reduction was significant (p < 0.01), d) a significant increase in IDEC and IDER in both exposed groups (p < 0.001). Our results evidence variations in oxidative balance and DNA damage in exposed workers. These findings represent a contribution to the sub-clinical evaluation of subjects exposed to agrochemicals in our country.

Evaluación bioquímica de trabajadores rurales expuestos a pesticidas / Biochemical evaluation on rural workers exposed to pesticides

Los pesticidas utilizados en agricultura pueden representar un riesgo potencial para la salud de los agricultores expuestos y para el medio ambiente. El objetivo de este trabajo fue evaluar trabajadores frutihortícolas expuestos a plaguicidas, categorizados por: exposición directa (n = 45), exposición indirecta (n = 50) y controles (n = 50) mediante biomarcadores de exposición y efecto: colinesterasa (ChE), acetilcolinesterasa (AChE), catalasa (CAT), peroxidación de lípidos (TBARS), Indice de Daño Ensayo Cometa (IDEC) e Indice de Daño Ensayo Reparación (IDER). Los resultados indican: a) inhibición significativa de AChE (p < 0.001) en expuestos directos e indirectos; b) aumento en los niveles de TBARS (p < 0.001) en los directos; c) reducción de CAT significativa (p < 0.01) y d) aumento de IDEC e IDER (p < 0.001) en ambos grupos. Los resultados obtenidos reflejan modificaciones en el balance oxidativo junto con daño al ADN en los trabajadores estudiados. Estos hallazgos representan una contribución en la evaluación subclínica de exposición a agroquímicos en nuestro país.

Pesticides are used in agriculture to protect crops but may represent a potential risk to farmers and the environment. The aim of this work was to evaluate horticultural workers exposed to pesticide, categorized by: direct exposure (n = 45), indirect exposure (n = 50) and controls (n = 50) using exposure and effect biomarkers: cholinesterase (ChE), acetylcholinesterase (AChE), catalase (CAT), lipid peroxidation (TBARS), Damage Index Comet Assay (IDEC) and Damage Index Repair Assay (IDER). Our results show: a) an AChE inhibition in directly and indirectly exposed population (p < 0.001), b) significant increase in the levels of TBARS in direct exposure (p < 0.001), c) the CAT reduction was significant (p < 0.01), d) a significant increase in IDEC and IDER in both exposed groups (p < 0.001). Our results evidence variations in oxidative balance and DNA damage in exposed workers. These findings represent a contribution to the sub-clinical evaluation of subjects exposed to agrochemicals in our country.

Análisis de polifenoles, actividad antioxidante y genotoxicidad en especies argentinas de Lippia y Aloysia (Verbenaceae) / Survey on polyphenols, antioxidant activity and genotoxicity on Argentinean species of Lippia and Aloysia (Verbenaceae)

Three species and a variety from the Verbenaceae belonging to the argentinean flora were analyzed: Aloysia gratissima var. gratissima (Gill. Et Hook) Tronc., Aloysia gratissima var. schulziana (Moldenke) Botta, Aloysia polystachya (Griseb.) Moldenke and Lippia integrifolia (Griseb.) Hieron., the first two known as “cedrón del monte”, the third as “yerba del burro” and the other as “incayuyo”. Their leaves are used as digestive in folk medicine. The research was performed on quantification of polyphenols (total phenols, total flavonoids and total hydroxicinnamic acids) and on determination of antioxidant and genotoxic activities. L. integrifolia showed the highest total phenol concentration and A. polystachya the lowest, but with the highest concentration of hydroxicinnamic acids. When flavonoids were quantified, A. polystachya showed the lowest concentations and A. gratissima var. schultziana the highest. According to quantification of total polyphenols, the lowest antioxidant activity was measured in A. polystachya extracts, followed by those from A. gratissima var. gratissima and A. gratissima var. schulziana, while extracts from L. integrifolia showed the highest antioxidant activity. No genotoxic activity was detected by means of the comet-assay for any of the species. This absence of genotoxicity, added to the relevant antioxidant activity, could justify the use of leaves infusions and decoctions from these species in treatments of those pathologies where antioxidants play an important role. These studies suggest their sure use in folk medicine, in which people include them among their medicinal plants.

Se analizaron 3 especies y una variedad de la familia Verbenaceae de la flora argentina: Aloysia gratissima var. gratissima (Gill. Et Hook) Tronc., Aloysia gratissima var. schulziana (Moldenke) Botta, Aloysia polystachya (Griseb.) Moldenke y Lippia integrifolia (Griseb.) Hieron., conocidas como “cedrón del monte” las dos primeras, “yerba del burro” la tercera e “incayuyo” la restante. De todas ellas se emplean las hojas en la medicina popular como digestivas. Se investigaron los contenidos de polifenoles (fenoles totales, flavonoides totales y ácidos hidroxicinámicos totales) y se determinó la capacidad antioxidante y genotoxicidad de las preparaciones acuosas (infusiones y cocimientos). L. integrifolia fue la especie con mayor contenido de fenoles totales y A. polystachya la menor. En el análisis de los hidroxicinámicos, A. polystachya fue la que mayor concentración mostró. En cuanto a los flavonoides, A. polystachya fue la que poseyó menor concentración en tanto que A. gratissima var. schultziana fue la más rica en estos compuestos. A. polystachya es la especie que presenta los menores valores de actividad antioxidante, seguida por A. gratissima var. gratissima y A. gratissima var. schulziana, mientras que L. integrifolia es la especie con mayor actividad antioxidante, en correlación con los valores de polifenoles totales. Ninguna de las especies analizadas demostró actividad genotóxica en el ensayo del cometa. La ausencia de genotoxicidad, sumada a una marcada actividad antioxidante, justificarían el empleo de las infusiones y cocimientos en el tratamiento de aquellas patologías donde los agentes antioxidantes juegan un importante rol terapéutico. Estos estudios sugieren el empleo seguro en la medicina tradicional de los pueblos y comunidades que las incluyen entre sus plantas medicinales.

Lymphocyte P-glycoprotein variability in healthy individuals / Variabilidad de la glicoproteína P linfocitaria en una población sana

The aim of the present work was to describe the distribution of lymphocyte P-glycoprotein activity on a population of healthy individuals, taking also into account sex and age. P-glycoprotein activity in lymphocytes was measured by the Rhodamine 123 efflux assay using flow cytometry, in the presence and absence of verapamil, a P-glycoprotein inhibitor. We obtained a range of P-glycoprotein activity from 1.04 to 3.79. The distribution of the activity in the population studied was better described by a bimodal model, according with the Kolmogorov-Smirnov test. The frequency adjusted to the following equation: F = 0.70 N (2.11; 0.43) + 0.30 N(3.29; 0.26), in which 0.70 and 0.30 represented the proportion of each group, and 0.43 and 0.26 were the standard deviations of the activity of each group, respectively. The study of the relationship between subjects´ age and P-glycoprotein activity showed no statistical significance. When healthy volunteers were separated according to sex, similar distributions were observed, although for men an increase in proportion of higher P-glycoprotein function group was observed. The variability observed in the population studied was important, with some volunteers with very scarce activity and some with a fourfold higher activity. Characterization of P-glycoprotein functionality in the population represents a useful contribution to the beginning of pharmacological treatments that consider its effect on pharmacokinetics and pharmacodynamics of individualized patients.

El objetivo del presente trabajo fue describir la distribución de la actividad de la glicoproteína P linfocitaria en una población de individuos sanos, considerando a su vez el sexo y la edad. La funcionalidad de la glicoproteína P fue determinada mediante el ensayo de eflujo de Rodamina 123, en presencia y ausencia de verapamilo, un inhibidor competitivo de este transportador, determinando la fluorescencia intracelular remanente mediante citometría de flujo. Obtuvimos un rango de actividades de entre 1.04 y 3.79. La distribución de la actividad en la población evaluada se ajusta a un modelo bimodal, según el test de Kolmogorov-Smirnov. La frecuencia ajusta a la siguiente ecuación: F = 0.70 N (2.11; 0.43) + 0.30 N (3.29; 0.26) donde 0.70 y 0.30 representan las proporciones de cada grupo, mientras que 0.43 y 0.26 corresponden al desvío estándar de la actividad de cada grupo respectivamente. Al estudiar la correlación entre la edad de los sujetos y la función de la proteína, no se observaron diferencias significativas. Cuando los individuos fueron clasificados en función del sexo, las distribuciones obtenidas fueron semejantes, aunque para los varones se observó un aumento en la proporción de individuos con alta actividad. La variabilidad observada fue importante, comprendiendo individuos con escasa actividad y otros que presentaron una actividad hasta cuatro veces mayor. La caracterización de la función de la glicoproteína P en la población representa una contribución indispensable para el desarrollo de tratamientos farmacológicos personalizados que consideren el efecto de dicho transportador en la farmacocinética y farmacodinámica de cada paciente.

[P-glycoprotein functional activity in peripheral blood lymphocytes in ulcerative colitis]. / Funcionalidad de la glicoproteína P linfocitaria en la colitis ulcerosa.

P-glycoprotein (P-gp), encoded by MDR-1, is a transmembrane efflux pump that has been involved in relevant clinical drug transport. It is expressed in lymphocytes, luminal epithelium of colon and other tissues with barrier function. MDR1 was proposed as a candidate gene for ulcerative colitis. The aim of the present work was to investigate the role of P-gp in therapeutic response of ulcerative colitis by studying its functionality in lymphocytes isolated from peripheral blood. Samples were taken from 27 patients with active colitis classified clinically in refractory (n = 16) and responders (n = 11) to treatment. Rhodamine 123 (a fluorescent P-glycoprotein substrate) efflux was studied by flow cytometry as absence and presence of an inhibitor (verapamil, 100 uM). Data were expressed evaluating the behaviour of two markers defined based on % of cells with maximum (M1)/minimum (M2) intracellular fluorescence, reflecting inactivity/activity of the pump. Results were compared with a group of healthy individuals (n = 68). Significant differences were observed in absence and presence of Verapamil inhibition, when comparing refractory vs. responders (p < 0.05) as well as refractory vs. healthy controls (p < 0.01). No differences were observed when comparing responders vs. controls (p > 0.05) (Kruskal-Wallis test and Dunn post-test). Rhodamine efflux assay was also performed in 12 patients who required therapeutic change; a significant diminish of rhodamine transport (p < 0.01) was observed without inhibitor when patients achieved clinical response. Finally, our results suggest a possible relevant role of P-gp in ulcerative colitis treatment response and a possible usefulness of P-gp functional assay in the early detection of individual therapeutic response.

Lymphocyte P-glycoprotein variability in healthy individuals.

The aim of the present work was to describe the distribution of lymphocyte P-glycoprotein activity on a population of healthy individuals, taking also into account sex and age. P-glycoprotein activity in lymphocytes was measured by the Rhodamine 123 efflux assay using flow cytometry, in the presence and absence of verapamil, a P-glycoprotein inhibitor. We obtained a range of P-glycoprotein activity from 1.04 to 3.79. The distribution of the activity in the population studied was better described by a bimodal model, according with the Kolmogorov-Smirnov test. The frequency adjusted to the following equation: F = 0.70 N (2.11; 0.43) + 0.30 N(3.29; 0.26), in which 0.70 and 0.30 represented the proportion of each group, and 0.43 and 0.26 were the standard deviations of the activity of each group, respectively. The study of the relationship between subjects' age and P-glycoprotein activity showed no statistical significance. When healthy volunteers were separated according to sex, similar distributions were observed, although for men an increase in proportion of higher P-glycoprotein function group was observed. The variability observed in the population studied was important, with some volunteers with very scarce activity and some with a fourfold higher activity. Characterization of P-glycoprotein functionality in the population represents a useful contribution to the beginning of pharmacological treatments that consider its effect on pharmacokinetics and pharmacodynamics of individualized patients.