Synergistic Interactions between Tocol and Phenolic Extracts from Different Tree Nut Species against Human Cancer Cell Lines.

Tree nuts are rich in polar (phenolic compounds) and non-polar (tocols) antioxidants, with recognized effects in the prevention of diseases such as cancer. These biomolecules possess antiproliferative activity on cancer cells; however, the combined effect of both types of compounds has been scarcely studied, and this approach could give valuable information on the real anticancer potential of tree nuts. In the present study, the antiproliferative activity of pure tocols and phenolic compounds, tocol- and phenolic-rich extracts (TRE and PRE, respectively) from tree nuts and the extracts combinations, was evaluated in four cancer (HeLa, MCF7, PC3, A549) and one control (ARPE) cell lines. The most sensible cell lines were HeLa and MCF7. TRE and PRE from nuts were chemically characterized; γ and δ tocopherols, total tocols, total tocopherols and total phenolic compounds were negatively correlated with cell viability in MCF7 cells. In HeLa cells, only δ and total tocopherols were negatively correlated with cell viability. TRE and PRE had a low effect in reducing cell viability of the cancer cell lines, the most effective extracts were those of emory oak acorn (EOA), pecan nut (PEC) and walnut (WAL), and these were further studied for their pharmacological interactions, using the combination index and the isobologram methods. Combinations of both extracts showed a synergistic and strongly synergistic behavior in the three nuts (EOA, PEC and WAL), with combination indexes between 0.12 and 0.55. These results highlight the need to understand the interactions among components found in complex natural extracts or food products in order to fully understand their bioactivities.

Sub-chronic consumption of a phenolic-rich avocado paste extract induces GLP-1-, leptin-, and adiponectin-mediated satiety in Wistar rats.

Avocado paste (AP) is a phenolic-rich byproduct of avocado oil extraction. The effects of sub-chronic consumption of diets supplemented with an AP phenolic extract (PE) were analyzed. A standard diet (SD), high-fat diet (HFD), and these supplemented with PE (SD + PE and HFD + PE) were used. Significantly increased satiety was observed in PE-supplemented groups, according to less food consumption (-15% in SD + PE vs. SD, and -11% in HFD + PE vs. HFD), without changes in weight gain or percentage of adipose tissue. PE-supplemented groups had an increased plasma concentration ( + 16% in SD + PE vs. SD, and +26% in HFD + PE vs. HFD) and relative mRNA expression (+74% in SD + PE vs. SD, and +46% in HFD + PE vs. HFD) of GLP-1; an increase in plasma leptin and adiponectin was independent of their mRNA expression. Our results suggest that AP-derived PE exerts a satiety effect in vivo, possibly mediated by GLP-1, leptin, and adiponectin. PRACTICAL APPLICATIONS: Minimizing food waste is a top priority in most of the world, thus, researchers seek methods to reintroduce industrial fruit and vegetable byproducts into the food processing chain. The present work highlights the potential of avocado byproducts as sources of bioactive phenolic compounds, whose sub-chronic consumption (8 weeks) exerts a satiety action in vivo. Avocado farming is resource-intensive, making it of relevance to producers and processing industries to avoid discarding its byproducts as much as possible.

An individualized food-based nutrition intervention reduces visceral and total body fat while preserving skeletal muscle mass in breast cancer patients under antineoplastic treatment.

BACKGROUND & AIMS: Breast cancer patients (BCP) during treatment often experience an increase in body weight and fat mass, and a decrease in muscle mass known as sarcopenic obesity, affecting their prognosis and quality of life. We aimed to evaluate the effect of a 6-month individualized food-based nutrition intervention program in nonmetastatic BCP body composition during treatment. METHODS: This is a pre-post study in recently diagnosed women with invasive ductal/lobular breast carcinoma (clinical stage I-III). The individualized nutrition intervention was based on the dynamic macronutrient meal equivalent menu method (MEM). Dietary plans were developed according to WCRF/AICR guidelines, BCP total energy expenditure, 1.2-1.5 g/kgBW/d of protein intake, 5-9 servings/day of fruits and vegetables, and a caloric restriction (500-1000 kcal/d) when applicable (BMI ≥ 25 kg/m2). Follow-up was every 2-weeks and a different diet menu was provided in each session during 6 months. Baseline and final measurements included the assessment of anthropometry, body composition, and physical activity. RESULTS: Twenty-two participants completed the study and at diagnosis 68% were overweighed or obese. After the 6-month nutrition intervention program, BCP lost 3.1 kg (p < 0.01) of body weight, 2.7 kg (p < 0.01) of fat-mass, 400 g (p < 0.01) of abdominal fat, 118 g (p < 0.05) of visceral fat, 1.2 kg/m2 of body mass index and 1.1 kg/m2 of fat mass index (p < 0.01). During the period, no changes were observed in bone mineral density (p = 0.3), fat-free mass (p = 0.1) and appendicular skeletal muscle mass (p = 0.2). Menopausal status in BCP did not modify the effect of the nutrition intervention. CONCLUSIONS: The individualized food-based nutrition intervention program empowered BCP to make informed healthy food choices within their personal preferences, socioeconomic and cultural background. With this type of intervention, nonmetastatic BCP reduced body weight, fat-mass, fat mass index, visceral and abdominal fat, while preserving skeletal muscle mass, during antineoplastic treatment. ClinicalTrials.govNCT03625635.

Neuroprotective effects of mango cv. 'Ataulfo' peel and pulp against oxidative stress in streptozotocin-induced diabetic rats.

BACKGROUND: Oxidative stress has been implicated in the pathogenesis and progression of diabetes mellitus. Both can damage the brain. Mango and its by-products are sources of bioactive compounds with antioxidant properties. We hypothesized that mango cv. 'Ataulfo' peel and pulp mitigate oxidative stress in the brain of streptozotocin-induced diabetic rats. RESULTS: Twenty-four male Wistar rats were divided into four groups: control, untreated diabetic (UD), diabetic treated with a mango-supplemented diet (MTD), and diabetic pretreated with a mango-supplemented diet (MPD). The rats were fed the different diets for 4 weeks after diabetes induction (MTD), or 2 weeks before and 4 weeks after induction (MPD). After the intervention, serum and brain (cerebellum and cortex) were collected to evaluate gene expression, enzyme activity, and redox biomarkers. Superoxide dismutase 2 (SOD2) expression increased in the cortex of the MTD group, whereas glutathione-S-transferase p1 (GSTp1) expression was higher in the cortex of the MTD group, and cortex and cerebellum of the MPD group. SOD1 activity was higher in the cerebellum and cortex of all diabetic groups, whereas GST activity increased in the cerebellum and cortex of the MPD group. Lipid peroxidation increased in the cerebellum and cortex of the UD group; however, a mango-supplemented diet prevented this increase in both regions, while also mitigating polyphagia and weight loss, and maintaining stable glycemia in diabetic rats. CONCLUSION: We propose that mango exerts potent neuroprotective properties against diabetes-induced oxidative stress. It can be an alternative to prevent and treat biochemical alterations caused by diabetes. © 2020 Society of Chemical Industry.

The "Super-Child" Approach Is Applied To Estimate Retinol Kinetics and Vitamin A Total Body Stores in Mexican Preschoolers.

BACKGROUND: Retinol isotope dilution (RID) and model-based compartmental analysis are recognized techniques for assessing vitamin A (VA) status. Recent studies have shown that RID predictions of VA total body stores (TBS) can be improved by using modeling and that VA kinetics and TBS in children can be effectively studied by applying population modeling ("super-child" approach) to a composite data set. OBJECTIVES: The objectives were to model whole-body retinol kinetics and predict VA TBS in a group of Mexican preschoolers using the super-child approach and to use model predictions of RID coefficients to estimate TBS by RID in individuals. METHODS: Twenty-four healthy Mexican children (aged 3-6 y) received an oral dose (2.96 µmol) of [13C10]retinyl acetate in corn oil. Blood samples were collected from 8 h to 21 d after dosing, with each child sampled at 4 d and at 1 other time. Composite data for plasma labeled retinol compared with time were analyzed using a 6-component model to obtain group retinol kinetic parameters and pool sizes. Model-predicted TBS was compared with mean RID predictions at 4 d; RID estimates at 4 d were compared with those calculated at 7-21 d. RESULTS: Model-predicted TBS was 1097 µmol, equivalent to ∼2.4 y-worth of VA; using model-derived coefficients, group mean RID-predicted TBS was 1096 µmol (IQR: 836-1492 µmol). TBS at 4 d compared with a later time was similar (P = 0.33). The model predicted that retinol spent 1.5 h in plasma during each transit and recycled to plasma 13 times before utilization. CONCLUSIONS: The super-child modeling approach provides information on whole-body VA kinetics and can be used with RID to estimate TBS at any time between 4 and 21 d postdose. The high TBS predicted for these children suggests positive VA balance, likely due to large-dose VA supplements, and warrants further investigation.

Arabinoxylan-Based Particles: In Vitro Antioxidant Capacity and Cytotoxicity on a Human Colon Cell Line.

Background and objectives: Arabinoxylans (AX) can gel and exhibit antioxidant capacity. Previous studies have demonstrated the potential application of AX microspheres as colon-targeted drug carriers. However, the cytotoxicity of AX gels has not been investigated so far. Therefore, the aim of the present study was to prepare AX-based particles (AXM) by coaxial electrospraying method and to investigate their antioxidant potential and cytotoxicity on human colon cells. Materials and Methods: The gelation of AX was studied by monitoring the storage (G') and loss (G'') moduli. The morphology of AXM was evaluated using optical and scanning electron microscopy (SEM). The in vitro antioxidant activity of AX before and after gelation was measured using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods. In addition, the effect of AX and AXM on the proliferation of human colon cells (CCD 841 CoN) was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results: The final G' and G'' values for AX gels were 293 and 0.31 Pa, respectively. AXM presented spherical shape and rough surface with a three-dimensional and porous network. The swelling ratio and mesh size of AXM were 35 g water/g AX and 27 nm, respectively. Gelation decreased the antioxidant activity of AX by 61-64 %. AX and AXM did not affect proliferation or show any toxic effect on the normal human colon cell line CCD 841 CoN. Conclusion: The results indicate that AXM could be promising biocompatible materials with antioxidant activity.

Mango phenolics increase the serum apolipoprotein A1/B ratio in rats fed high cholesterol and sodium cholate diets.

BACKGROUND: Serum lipoproteins are in dynamic equilibrium, partially controlled by the apolipoprotein A1 to apolipoprotein B ratio (APOA1/APOB). Freeze-dried mango pulp (FDM) is a rich source of phenolic compounds (MP) and dietary fiber (MF), although their effects on lipoprotein metabolism have not yet been studied. RESULTS: Thirty male Wistar rats were fed with four different isocaloric diets (3.4 kcal g-1 ) for 12 weeks: control diet, high cholesterol (8 g kg-1 ) + sodium cholate (2 g kg-1 ) diet either alone or supplemented with MF (60 g kg-1 ), MP (1 g kg-1 ) or FDM (50 g kg-1 ). MP and FDM reduced food intake, whereas MF and MP tended to increase serum APOA1/APOB ratio, independently of their hepatic gene expression. This suggests that lipoprotein metabolism was favorably altered by mango bioactives, MP also mitigated the non-alcoholic steatohepatitis that resulted from the intake of this diet. CONCLUSION: We propose that phenolics are the most bioactive components of mango pulp, acting as anti-atherogenic and hepatoprotective agents, with a mechanism of action tentatively based on changes to the main protein components of lipoproteins. © 2018 Society of Chemical Industry.

Selected Physiological Effects of a Garcinia Gummi-Gutta Extract in Rats Fed with Different Hypercaloric Diets.

Garcinia gummi-gutta (GGG) rind extract is effective for reducing appetite, body weight and adiposity of obese rodents fed high-fat (HF), high-sugar (HS) or high fat/sugar (HFS)-based diets, but these effects have not been simultaneously evaluated. Thirty obese (~425 g) male Wistar rats were fed for eleven weeks with six hypercaloric diets (4.1 kcal/g; five rats/diet) non-supplemented (HF, HS, HFS), or supplemented (HF+, HS+, HFS+) with GGG extract (5.9%), while rats from the control group (375 g) were fed a normocaloric diet (3.5 kcal/g). Body weight, dietary intake, body fat distribution, and histological and biochemical parameters were recorded. Compared to control rats, non-supplemented and supplemented groups consumed significantly less food (14.3% and 24.6% (−4.3 g/day), respectively) (p < 0.05). Weight loss was greater in the HF+ group (35⁻52 g), which consumed 1.9 times less food than the HS+ or HFS+ fed groups. The HF and HFS groups showed 40% less plasma triacylglycerides and lower glucose levels compared to the HF+. GGG-supplemented diets were associated with lower ketonuria. The HF+ diet was associated with the best anti-adiposity effect (as measured with the dual X-ray absorptiometry (DXA) and Soxhlet methods). The severity of hepatocyte lipidosis was HF > control > HF+, and no signs of toxicity in the testes were observed. The results indicate that GGG is more effective when co-administered with HF diets in obese rats.

Randomized double-blind controlled clinical trial of the blood pressure-lowering effect of fermented milk with Lactococcus lactis: A pilot study.

The blood pressure-lowering effect of fermented milk with Lactococcus lactis NRRL B-50571 was evaluated in a double-blind randomized controlled clinical trial with prehypertensive subjects. Participants were randomized into 2 groups (n = 18 each group): one group treated with fermented milk with Lactococcus lactis NRRL B-50571 and a control group treated with artificially acidified milk. Results revealed that during daily consumption of fermented milk for 5 wk, systolic [(116.55 ± 12.26 mmHg vs. 124.77 ± 11.04 mmHg) and diastolic blood pressure (80.7 ± 9 vs. 84.5 ± 8.5 mmHg)] from the fermented milk group was lower than the control group. Additionally, triglyceride, total cholesterol, and low-density lipoprotein in blood serum were lower in the fermented milk group than in the control group. Results demonstrated that daily consumption of fermented milk with Lactococcus lactis (NRRL B-50571) had a blood pressure-lowering effect on prehypertensive subjects. Regular consumption of this product may be used as a potential functional food.

Antineoplastic treatment effect on bone mineral density in Mexican breast cancer patients.

BACKGROUND: Breast cancer is the most deadly malignancy in Mexican women. Although treatment has improved, it may significantly affect bone mineral status in those who receive it. The aim of this study was to assess the impact of cancer treatment on bone mineral density (BMD) and bone mineral content (BMC), in patients with breast cancer and explore the interaction of menopausal status and clinical stage with cancer treatment on such changes. METHODS: A quasi-experimental design was applied with measurements before and after a chemotherapy treatment in 40 patients with primary diagnosis of invasive breast cancer. BMD and body composition measurements were taken by dual X-ray absorptiometry (DXA) and changes in these variables due to therapy were analyzed using mixed regression for repeated measurements. RESULTS: Significant loss was found in femoral neck and L2-L4 BMD (p < 0.001). Patients diagnosed with osteopenia or osteoporosis received calcium + vitamin D supplementation (600 mg/200 IU day). It showed a protective effect in the decrease of femoral neck BMD and total BMC. BMD loss in both femoral neck and L2-L4 BMD was higher in premenopausal women: 0.023 g/cm2 in femoral neck and 0.063 g/cm2 in L2-L4 (p < 0.001), while in postmenopausal women BMD loss was 0.015 g/cm2 in femoral neck and 0.035 g/cm2 in L2-L4 (p = 0.021 and p = 0.001 respectively). Change in lumbar spine BMD was prominent in premenopausal women with advanced clinical stage (IIB, IIIA, IIIB): 0.066 g/cm2 (p = 0.003). CONCLUSION: The antineoplastic breast cancer treatment with chemotherapy had a negative impact on BMD, in premenopausal women overall, although a differential effect was found according to clinical stage and calcium supplementation status.

Influence of Sorghum Kafirin on Serum Lipid Profile and Antioxidant Activity in Hyperlipidemic Rats (In Vitro and In Vivo Studies).

The aim of this study was to compare in vitro the antioxidant potential of sorghum kafirin and sorghum flour and their influence on lipids and antioxidant capacity in rats. The antioxidant activity in sorghum kafirin extract measured by the DPPH and TEAC methods was increased 30 and 65 times, respectively, compared to that of its counterpart, sorghum flour. According to electrophoresis assay, the kafirins tert-butanol extract showed a high proportion of α-kafirin monomers, and its amino acid composition revealed higher hydrophobic amino acid content such as alanine, isoleucine, leucine, tyrosine and phenylalanine than sorghum flour extract. Diets supplemented with sorghum kafirin extract have improved lipid metabolism and increased the serum antioxidant potential (67%) especially in rats fed with added cholesterol. The bioactive peptides generated from kafirin in vivo hydrolysis appear to be associated with the positive effect on serum lipids and antioxidant activity. According to these results, sorghum kafirin extract at the levels used in this study apparently could be used for prevention of atherosclerosis and other chronic diseases.

Crosstalk between Zinc Status and Giardia Infection: A New Approach.

Zinc supplementation has been shown to reduce the incidence and prevalence of diarrhea; however, its anti-diarrheal effect remains only partially understood. There is now growing evidence that zinc can have pathogen-specific protective effects. Giardiasis is a common yet neglected cause of acute-chronic diarrheal illness worldwide which causes disturbances in zinc metabolism of infected children, representing a risk factor for zinc deficiency. How zinc metabolism is compromised by Giardia is not well understood; zinc status could be altered by intestinal malabsorption, organ redistribution or host-pathogen competition. The potential metal-binding properties of Giardia suggest unusual ways that the parasite may interact with its host. Zinc supplementation was recently found to reduce the rate of diarrhea caused by Giardia in children and to upregulate humoral immune response in Giardia-infected mice; in vitro and in vivo, zinc-salts enhanced the activity of bacitracin in a zinc-dose-dependent way, and this was not due to zinc toxicity. These findings reflect biological effect of zinc that may impact significantly public health in endemic areas of infection. In this paper, we shall explore one direction of this complex interaction, discussing recent information regarding zinc status and its possible contribution to the outcome of the encounter between the host and Giardia.

[Antineoplastic treatment impact on nutritional status in patients with breast cancer]. / Impacto del tratamiento antineoplásico en el estado nutricional en pacientes con cáncer de mama.

BACKGROUND: Breast cancer is the most commonly diagnosed malignancy in women in Mexico and also has the highest mortality. Although treatment has improved significantly, it can affect the nutritional status of the recipients. OBJECTIVE: The aim of this study was to assess the impact of the initial phase of antineoplastic therapy on the nutritional status in patients with breast cancer. METHODS: Forty subjects with primary diagnosed of invasive breast cancer were studied in a before and after intervention (six month apart) using a quasi-experimental design. Basal and six month after intervention measurements included were anthropometry, body composition by dual X-ray absorptiometry (DEXA), diet by 24-hour recall and food frequency questionnaire, as well as serum -carotene and retinol. The therapy effect was analyzed using repeated measurements mixed linear regression. RESULTS: Lean tissue decreased after the studied period (p=0.032). Addicionally, there was an interaction between weight, BMI and body fat parameters with menopausal status, increasing in these variables due to therapy only premenopausal patients (p=0.005, 0.006 and 0.001, respectively). Decreased serum retinol (p=0.049) despite the improvement in -carotene status (p=0.03). In general there was an increase the consumption of vegetables food products whilst a decrease in animal foods. CONCLUSION: The breast cancer antineoplastic treatment had a negative effect on weight and body fat, especially in young women. Although there were some positive dietary changes, vegetables consumption remained insufficient, which was also reflected in serum biomarkers.

Presentación: El cáncer de mama es el tipo de tumor más frecuentemente diagnosticado entre las mujeres de México y también el de más alta mortalidad. Aunque el tratamiento ha mejorado significativamente, puede afectar al estado nutricional del paciente. Objetivo: El objetivo de este estudio era evaluar el impacto de la fase inicial de la terapia antineoplásica sobre el estado nutricional en pacientes con cáncer de mama. Métodos: Cuarenta sujetos con diagnóstico primario de cáncer de mama invasivo fueron estudiados antes y después de la intervención (con seis meses de desfase) usando un diseño quasi-experimental. Las mediciones al inicio y seis meses después de la intervención incluyeron antropometría, composición corporal mediante absorciometría dual de rayos X (DEXA), cuestionario de recopilación de dieta en 24 horas y frecuencia de comidas, y suero beta-caroteno y retinol. El efecto de la terapia fue analizado empleando mediciones repetidas y regresión lineal mixta. Resultados: El tejido magro disminuyó tras el periodo de estudio (p=0.032). Además, se dio una interacción entre los parámetros de peso, IMC y grasa corporal con el estado de menopausia, aumentando en estas variables debido a la terapia solo en pacientes premenopáusicas (p=0.005, 0.006 y 0.001, respectivamente). Descenso de retinol sérico (p=0.049) a pesar de la mejoría en el estado de beta-caroteno (p=0.03). En general hubo un aumento en el consumo de verdura y un descenso de productos animales. Conclusión: El tratamiento antineoplásico del cáncer de mama tuvo un efecto negativo sobre el peso y la grasa corporal, especialmente en mujeres jóvenes. Aunque se observaron algunos cambios positivos en la dieta, el consumo de verdura siguió siendo insuficiente, lo que también se reflejó en los biomarcadores séricos.

Impacto del tratamiento antineoplásico en el estado nutricional en pacientes con cáncer de mama / Antineoplastic treatment impact on nutritional status in patients with breast cancer

Introducción: El cáncer de mama es la neoplasia más diagnosticada en mujeres en México y también la de mayor mortalidad. Aunque el tratamiento ha mejorado, puede afectar de forma importante el estado nutricio de quienes lo reciben. Objetivo: Evaluar el impacto del tratamiento antineoplásico sobre el estado nutricio en pacientes con cáncer de mama. Pacientes y métodos: Se aplicó un diseño cuasiexperimental, antes y después de seis meses del inicio del tratamiento quimioterapéutico. Participaron 40 pacientes con diagnóstico primario de cáncer de mama invasivo. Se tomaron medidas antropométricas, de composición corporal mediante absorciometría dual de rayos X (DEXA) así como análisis de la dieta mediante recordatorio de 24 horas y cuestionario de frecuencia de consumo. Además, se cuantificaron los biomarcadores séricos, retinol y Beta-caroteno. El efecto del tratamiento se estimó utilizando regresión linear mixta para mediciones repetidas. Resultados: Se registró una pérdida de tejido magro (p=0.03). Además se encontró interacción del climaterio sobre los parámetros de peso, IMC y grasa corporal; solo en las pacientes preclimatéricas aumentaron estas medidas (p=0.005, 0.006 y 0.001 respectivamente). El retinol sérico disminuyó (p=0.049) pese al incremento en el Beta-caroteno (p=0.030). También se incrementó el consumo de vegetales y hubo una reducción en el consumo de alimentos de origen animal. Conclusión: El tratamiento antineoplásico para cáncer de mama afectó negativamente al peso y grasa corporal, principalmente en las mujeres jóvenes. Pese a las modificaciones dietarias, el consumo promedio de vegetales aún es insuficiente, lo cual se reflejó también en los biomarcadores séricos (AU)

Background: Breast cancer is the most commonly diagnosis malignancy in women in Mexico and also has the highest mortality. Although treatment has improved significantly, it can affect the nutritional status of the recipients. Objective: The aim of this study was to assess the impact of the initial phase of antineoplastic therapy on the nutritional status in patients with breast cancer. Methods: Forty subjects with primary diagnosed of invasive breast cancer were study in a before and after intervention (six months apart) using a quasi-experimental design. Basal and six month after intervention measurements included were anthropometry, body composition by dual X-ray absorptiometry (DEXA), diet by 24-hour recall and food frequency questionnaire, as well as serum Beta-carotene and retinol. The therapy effect was analyzed using repeated measurements mixed linear regression. Results: Lean tissue decreased after the studied period (p=0.032).Addicionally, there was an interaction between weight, BMI and body fat parameters with menopausal status, increasing in these variables due to therapy only premenopausal patients (p=0.005, 0.006 and 0.001, respectively). Serum retinol decreased (p=0.049) despite the improvement in Beta-carotene status (p=0.03). In general there was an increase the consumption of vegetables food products whilst a decrease in animal foods products. Conclusion: The breast cancer antineoplasic treatment had a negative effect on weight and body fat, especially in young women. Although there were some positive dietary changes, vegetables consumption remained insufficient, which was also reflected in serum biomarkers (AU)

Marked antigiardial activity of Yucca baccata extracts: a potential natural alternative for treating protozoan infections.

Human giardiosis is a public health problem in Mexico, where the national prevalence was estimated to be up to 68%. Misuse of antiprotozoal drugs may result in low effectiveness and undesirable side effects. Research on natural products is a good strategy for discovering more effective antiparasitic compounds. This study evaluated the antigiardial activity of extracts of Yucca baccata, which is native to northwestern Mexico. Forty-two gerbils (females) were weighed and orally inoculated with 5 × 10(6) Giardia trophozoites. Two gerbils were selected at random to confirm infection. Forty living gerbils were randomly allocated into 5 treatment groups (8 per group). Gerbils were randomly assigned to be treated with 24.4 mg/mL, 12.2 mg/mL, and 6.1 mg/mL of extracts, metronidazole (2 mg/mL) or PBS, which were intragastrically administered once per day for 3 days. Nine gerbils died during the study course. On day 10 postinfection, gerbils were euthanized and trophozoites were quantified. Yucca extracts reduced, albeit not significantly, the trophozoite counts in the duodenum segment. Only the high-extract concentration significantly reduced the trophozoite counts in the proximal segment and it was similar to that of metronidazole. Extracts of Y. baccata may represent an effective and natural therapeutic alternative for human giardiosis.

Effects of dietary zinc manipulation on growth performance, zinc status and immune response during Giardia lamblia infection: a study in CD-1 mice.

Associations between Giardia lamblia infection and low serum concentrations of zinc have been reported in young children. Interestingly, relatively few studies have examined the effects of different dietary zinc levels on the parasite-infected host. The aims of this study were to compare the growth performance and zinc status in response to varying levels of dietary zinc and to measure the antibody-mediated response of mice during G. lamblia infection. Male CD-1 mice were fed using 1 of 4 experimental diets: adequate-zinc (ZnA), low-zinc (ZnL), high-zinc (ZnH) and supplemented-zinc (ZnS) diet containing 30, 10, 223 and 1383 mg Zn/kg respectively. After a 10 days feeding period, mice were inoculated orally with 5 × 106 G. lamblia trophozoites and were maintained on the assigned diet during the course of infection (30 days). Giardia-free mice fed ZnL diets were able to attain normal growth and antibody-mediated response. Giardia-infected mice fed ZnL and ZnA diets presented a significant growth retardation compared to non-infected controls. Zinc supplementation avoided this weight loss during G. lamblia infection and up-regulated the host's humoral immune response by improving the production of specific antibodies. Clinical outcomes of zinc supplementation during giardiasis included significant weight gain, higher anti-G. lamblia IgG antibodies and improved serum zinc levels despite the ongoing infection. A maximum growth rate and antibody-mediated response were attained in mice fed ZnH diet. No further increases in body weight, zinc status and humoral immune capacity were noted by feeding higher zinc levels (ZnS) than the ZnH diet. These findings probably reflect biological effect of zinc that could be of public health importance in endemic areas of infection.

Vitamin A-fortified milk increases total body vitamin A stores in Mexican preschoolers.

Vitamin A (VA) deficiency (VAD) continues to be a major nutritional problem in developing countries, including Central America. In Mexico, milk is a well-accepted vehicle for the administration of micronutrients, including VA, to preschoolers. Thus, we conducted a randomized, controlled, clinical trial to investigate the efficacy of daily consumption of 250 mL of VA-fortified milk (which provided 196 retinol equivalents/d) for 3 mo on VA stores in mildly to moderately VAD (serum retinol concentration 0.35-0.7 µmol/L) preschoolers who were not enrolled in a food assistance program. Twenty-seven mildly to moderately VAD children were randomly assigned based on screening measurements to either the intervention (n = 14) or control group (n = 13) (children in the control group did not receive placebo). All children in the control group and 79% (n = 11) of the children in the intervention group completed the study. The total body VA (TBVA) pool size was estimated using the deuterated retinol dilution technique before and after the intervention. After 3 mo, median changes in the serum retinol concentration for the intervention and control groups were 0.13 and -0.21 µmol/L, respectively (P = 0.009). Median changes in the TBVA stores were 0.06 and 0.01 mmol, respectively (P = 0.006) and estimated median changes in the liver VA concentration were 0.09 and 0.01 µmol/g, respectively (P = 0.002). The VA-fortified milk was well accepted among preschoolers and significantly increased TBVA stores, liver VA stores, and serum retinol concentration, indicating that it may be an effective means to ameliorate VAD in young Mexican children.

Physiological effects beyond the significant gain in muscle mass in sarcopenic elderly men: evidence from a randomized clinical trial using a protein-rich food.

BACKGROUND: Sarcopenia is strongly associated with an inadequate intake of dietary protein. Dietary protein supplementation boosts muscle-protein synthesis and increases muscle mass in the elderly. This study tested whether adding a protein-rich food, ricotta cheese, to the habitual diet increased total appendicular skeletal muscle mass and strength in elderly people. METHODS: Participants (n = 40), were sarcopenic elderly men and women over 60 years of age. Two comparison groups were formed at random and followed for 3 months: the intervention group received 210 g/day of ricotta cheese plus the habitual diet, while the control group followed the habitual diet with no additional intervention. Total appendicular skeletal muscle (TASM) was assessed by dual-energy X-ray absorptiometry, while strength was measured using a handheld dynamometer at baseline and after the intervention period. The primary outcomes were the percentage of relative change in TASM and strength. RESULTS: The percentage of relative change in TASM was not significant between the groups after the intervention period. Muscle strength improved in the intervention group, but showed only a tendency towards significance (P = 0.06). Secondary analysis showed that the men in the intervention group gained 270 g in TASM compared to those in the control group, and improved their fasting insulin levels (P = 0.05), muscle strength, lean body mass in the arms, and body weight variables. CONCLUSION: The results of this study indicate that a nutritional intervention using a high-quality protein food, specifically ricotta cheese, in order to increase the amount of protein intake might not be regarded as fully promising in elderly men and women with sarcopenia. However, the gender effects on muscle strength, lean tissue in the arms, homeostatic assessment of insulin resistance, and body weight detected in this study suggest that additional research is needed on elderly male subjects with sarcopenia.

Efecto de la suplementación con una dosis masiva de vitamina A en niños de 6 a 36 meses de edad / Effect of massive vitamin A supplement in children from 6 to 36 months of age

Objetivo. Evaluar el impacto de la suplementación con una dosis masiva de vitamina A en el estado nutricio de dicha vitamina y del hierro, en niños de zonas urbanas marginadas de Hermosillo, Sonora, México. Material y métodos. Se seleccionaron 60 niños (6-36 meses), a los que se les administró una dosis de 100 00 UI (6-12 meses) y 200 000 UI (12-36 meses) de vitamina A en el Día Nacional de Salud de la Secretaría de Salud (junio de 1994). Se midieron niveles séricos de retinol, carotenioide, hierro, transferrina y ferritina, en tres fases: basal, a las dos semanas y después de tres meses. Resultados. En la primera fase, la mediana de retinol fue 0.7 µmol/l; en la segunda aumentó a 0.97 µmol/l (p< 0.001), y en la tercera disminuyó a 0.83 µmol/l (p> 0.05). Un 6.3 por ciento de los niños presentó deficiencia severa de vitamina A al inicio, y no se encontró ningún caso en las fases posteriores a la suplementación. En la fase basal, 42 por ciento de los casos presentaron deficiencia moderada y la mayoría fue normal en las siguientes fases. No hubo diferencias en los niveles de hierro y transferrina (p> 0.05), pero sí en ferritina (p< 0.001), lo que indica un mejoramiento en las reservas de hierro a los tres meses. Conclusiones. Las campañas de distribución de dosis masivas pueden tener un impacto importante en el estado nutricio de vitamina A y hierro