Study of pH and Thermodynamic Parameters via Circular Dichroism Spectroscopy of a Recombinant Human Lactoferrin.

The production of human recombinant proteins to be used for therapeutic or nutritional purposes must focus on obtaining a molecule that is as close as possible to the native human protein. This biotechnological tool has been documented in various studies published in recent decades, with lactoferrin being one of those that has generated the most interest, being a promising option for recombinant technology. However, stability studies including thermodynamic parameters have not been reported for recombinant lactoferrin (Lf). The objective of this work was to obtain the human recombinant protein using the yeast Komagataella phaffii to study structural changes modifying pH and temperature using circular dichroism spectroscopy (CD). Thermodynamic parameters such as ΔH, ΔS and Tm were calculated and compared with commercial human lactoferrin. We propose the potential use of CD and thermodynamic parameters as a criterion in the production of recombinant proteins to be used in the production of specialized recombinant proteins.

Effects of ALAD genotype on the relationship between lead exposure and anthropometry in a Cohort of Mexican children.

OBJECTIVES: Lead exposure is associated with children's growth, but this relationship may depend on the presence of susceptibility factors, including genetic variation. Blood lead levels (BLL) differ by ALAD (aminolevulinic acid dehydratase) genotype. We investigated the association between BLL and growth in Mexican first-graders with different ALAD genotypes. METHODS: Children between the ages of 6-8 years (n = 602) attending first grade in schools within the vicinity of a metal foundry in Torreón, Mexico were enrolled into a randomized controlled trial (RCT) testing the efficacy of iron and/or zinc supplementation on blood lead levels (BLL) and cognition. BLL and anthropometry were assessed at baseline (height, height-for-age z-score (HAZ), knee height, head circumference), after 6 (head circumference) and 12 months (height, HAZ, knee height). Children with ALAD1-1 and ALAD1-2/2-2 were compared. The study sample included 538 and 470 participants who had complete data at baseline and follow-up, respectively. Separate multivariable linear regression models adjusted for covariates were used to test the association between BLL at baseline and each anthropometric measure. Covariates included age, sex, hemoglobin, crowding, and maternal education. BLL x ALAD genotype interaction term was tested. RESULTS: Median BLL (10.1 µg/dL) did not differ by ALAD genotype. After covariate adjustment, baseline BLL was inversely associated with baseline height, HAZ, and knee height. The association (ß [95% CI]) between BLL and baseline height (-0.38[-0.68, -0.09]), HAZ (-0.07[-0.12, -0.02]) and knee height (-0.14[-0.25, -0.02]), was somewhat stronger in children with ALAD1-2/2-2 than ALAD1-1 (-0.09[-0.16, -0.02], -0.02[-0.03, -0.004] and -0.04[-0.06, -0.01], respectively). No associations between BLL and growth at 6 or 12 months were detected irrespective of ALAD genotype. CONCLUSIONS: BLL was adversely associated with anthropometric measures among Mexican children. ALAD genotype may be a susceptibility factor for the effects of lead on child growth.

Association between obesity and depressive symptoms in Mexican population.

PURPOSE: Obesity and depression are among the leading causes of disability in Mexico, but their association has not been explored yet. The aim of the current study was to investigate the association between obesity and depression in Mexican population. METHODS: We used data from the health and nutrition survey (ENSANUT 2012), which is representative of the Mexican population. Obesity was determined using the body mass index (BMI) and abdominal obesity by measuring waist circumference. Depressive symptoms were reported using the Center for Epidemiological Studies Depression Scale Short-Form (CES-D-SF, scale 0-21). Regression analyses were performed between obesity and depression, adjusting for gender, age, living with a partner, education, and diabetes history. RESULTS: Obese women had 1.28 (95% CI 1.07-1.53) times the odds of having depression in comparison with normal-weight women, whereas no association was found for men (OR 0.94; 95% CI 0.74-1.19). A significant association between BMI and depressive symptoms score (ß = 0.05, 95% CI 0.02-0.07) was present in women, but no association was found for men (ß = - 0.02, 95% CI - 0.05 to 0.00). There was a statistically significant association between waist circumference and depression scores again for women (ß = 0.03, 95% CI 0.01-0.04) but not for men (ß = 0.00, 95% CI - 0.01 to 0.01). No associations were found between abdominal obesity and depression for both genders. No association was found between different obesity severity levels and depression for both genders. CONCLUSION: Obesity was associated with depression in Mexican women, whereas no association was found between obesity and depression in men.

Iron and Zinc Supplementation Does Not Impact Urinary Arsenic Excretion in Mexican School Children.

OBJECTIVE: To examine the role of iron and zinc in arsenic excretion and metabolism in children. STUDY DESIGN: An analysis of urinary arsenic (UAs) concentrations from a double-blind randomized trial originally testing the efficacy of iron and zinc for lowering blood lead levels in children. A 2 × 2 factorial design was used, with children randomized individually, stratified by sex and classroom, to receive 30?mg ferrous fumarate (n?=?148), 30?mg zinc oxide (n?=?144), iron and zinc together (n?=?148), or placebo (n?=?151). Of the 602 children enrolled, 527 completed the 6-month treatment, and 485 had both baseline and final UAs values. The baseline total UAs concentration ranged from 3.2 to 215.9?µg/L. RESULTS: At baseline, children in the highest tertile of serum ferritin concentration had higher excretion of dimethylarsinic acid (DMA; 1.93?±?0.86%; P?

Fat mass obesity-associated (FTO) (rs9939609) and melanocortin 4 receptor (MC4R) (rs17782313) SNP are positively associated with obesity and blood pressure in Mexican school-aged children.

Childhood overweight and obesity are worldwide public health problems and risk factors for chronic diseases. The presence of SNP in several genes has been associated with the presence of obesity. A total of 580 children (8-13 years old) from Queretaro, Mexico, participated in this cross-sectional study, which evaluated the associations of rs9939609 (fat mass obesity-associated (FTO)), rs17782313 (melanocortin 4 receptor (MC4R)) and rs6548238 (transmembrane protein 18 (TMEM18)) SNP with obesity and metabolic risk factors. Overweight and obesity prevalence was 19·8 and 19·1 %, respectively. FTO, MC4R and TMEM18 risk allele frequency was 17, 9·8 and 89·5 %, respectively. A significant association between FTO homozygous and MC4R heterozygous risk alleles and obesity was found (OR 3·9; 95 % CI 1·46, 10·22, and OR 2·1; 95 % CI 1·22, 3·71; respectively). The FTO heterozygous subjects showed higher systolic and diastolic blood pressures, compared with the homozygous for the ancestral allele subjects. These results remain significant after considering adiposity as a covariate. The FTO and MC4R genotypes were not significantly associated with total cholesterol, HDL-cholesterol and insulin concentration. No association was found between TMEM18 risk allele and obesity and/or metabolic alterations. Our results show that, in addition to a higher BMI, there is also an association of the risk genotype with blood pressure in the presence of the FTO risk genotype. The possible presence of a risk genotype in obese children must be considered to offer a more comprehensive therapeutic approach in order to delay and/or prevent the development of chronic diseases.

Sex differences in the reduction of arsenic methylation capacity as a function of urinary total and inorganic arsenic in Mexican children.

Chronic arsenic (As) exposure decreases adult and children's ability to methylate inorganic As (iAs); however, few studies have examined children's sex differences. We measured urinary concentrations of iAs, monomethylarsonic (MMA), and dimethylarsinic (DMA) acids, and calculated the primary (PMI: MMA/iAs) and secondary (SMI: DMA/MMA) methylation capacity indexes in 591 children 6-8 years in Torreón, Mexico. We determined iAs, MMA, and DMA by hydride generation cryotrapping AAS. Lineal regression models estimated associations between methylation capacity and total As (TAs) or iAs. Interactions with sex were tested at p<0.10. Boys had significantly higher TAs levels, (58.4µg/L) than girls (46.2µg/L). We observed negative associations between TAs and PMI (ß=-0.039; p<0.18) and SMI (ß=-0.08; p=0.002) with significant sex differences; PMI reduction was significant in boys (ß=-0.09; p=0.02) but not in girls (ß=0.021; p=0.63), p for interaction=0.06. In contrast, SMI reduction was significantly more pronounced in girls. Furthermore, negative associations PMI (ß=-0.19; p<0.001) and SMI (ß=-0.35; p<0.001) were a function of urinary iAs levels, independently of TAs; however, the reduction in PMI was more pronounced in boys (ß=-0.24; p<0.001; girls ß=-0.15; p<0.001), p for interaction=0.04. A significant negative association was observed between SMI and iAs levels without significant sex differences. TAs and iAs associations with metabolite percentages were in good agreement with those observed with methylation indexes. Our results suggest that iAs plays an important role in reducing As methylation ability and that significant sex differences are present in As metabolism. These differences merit further investigation to confirm our findings and their potential implications for arsenic toxicity in children.

Beliefs and motives related to eating and body size: a comparison of high-BMI and normal-weight young adult women from rural and urban areas in Mexico.

BACKGROUND: Effective treatment and prevention of obesity and its co-morbidities requires the recognition and understanding of cultural and social aspects of eating practices. The objective of the present study was to identify social factors and beliefs that may explain undesirable eating practices among women with high body mass index (HBMI) compared with normal-weight (NW) women from rural and urban areas classified as middle-low socioeconomic status (SES) in the State of Querétaro, Mexico. METHODS: A qualitative technique with individual in-depth interviews was used. Fifty-five women with either NW or HBMI from rural and urban areas participated in the study. The responses were analyzed by coding and grouping text fragments into categories in a data matrix, in order to make comparisons between BMI groups and between rural and urban women. RESULTS: The habit of skipping breakfast prevailed among women with HBMI who also reported childhood food deprivation. Feelings related to eating seemed to be more important than losing weight among women with HBMI from urban and rural areas. Thus, overweight might be interpreted as a social symbol of the enjoyment of a good life, primarily in rural areas. Overweight was socially accepted when it occurred in children and in married woman, mainly because it is a symbol of the good life that the head of the household provides, and also because women may feel more relaxed about their weight when they already have a partner. The study also revealed that women with HBMI were not sufficiently motivated to lose weight unless they experience a physical indication of poor health. CONCLUSION: The findings from this study are helpful in the understanding of the reasons why strategies for the prevention and treatment of obesity may not be as effective as expected. The belief system of particular social groups within different SESs should be considered in order to understand the etiology of obesity and develop effective strategies.

4-Hydroxyisoleucine from Fenugreek (Trigonella foenum-graecum): Effects on Insulin Resistance Associated with Obesity.

Obesity and insulin resistance (IR) are interdependent multifactorial processes that cannot be understood separately. Obesity leads to systemic inflammation and increased levels of free fatty acids that provoke IR and lipotoxicity. At the same time, IR exacerbates adipose cell dysfunction, resulting in chronic inflammation and major lipotoxic effects on nonadipose tissues. 4-Hydroxyisoleucine (4-OHIle), a peculiar nonprotein amino acid isolated from fenugreek (Trigonella foenum-graecum) seeds, exhibits interesting effects on IR related to obesity. 4-OHIle increases glucose-induced insulin release, and the insulin response mediated by 4-OHIle depends on glucose concentration. The beneficial effects observed are related to the regulation of blood glucose, plasma triglycerides, total cholesterol, free fatty acid levels, and the improvement of liver function. The mechanism of action is related to increased Akt phosphorylation and reduced activation of Jun N-terminal kinase (JNK)1/2, extracellular signal-regulated kinase (ERK)1/2, p38 mitogen-activated protein kinase (MAPK), and nuclear factor (NF)-κB. Here, we present a review of the research regarding the insulinotropic and insulin-sensitising activity of 4-OHIle in in vitro and in vivo models.

[Lactose intolerance]. / Intolerancia a la lactosa.

The most common problem limiting milk consumption worldwide is lactose intolerance (LI), which is defined as the experience of gastrointestinal symptoms due to the intake of lactose-containing food. When symptoms ensue the intake of milk, the condition is referred as milk intolerance, and it may or may not be due to LI. The most common cause of LI is primary lactase deficiency which occurs in 30% of Mexican adults when one glass of milk is consumed (12-18 g of lactose). LI occurs in less than 15% of adults after the intake of this dose of lactose. Another cause of lactose intolerance is due to secondary lactase deficiency, which occurs because lactase is reduced due to diseases that affect the intestinal mucosa. Lactose intolerance can be eliminated or significantly reduced by elimination or reduction of the intake of milk and milk containing products. Recent studies demonstrate that when ß-casein-A1 contained in milk is hydrolyzed it produces ß-casomorphine-7 which is an opioid associated with milk intolerance.

Effect of a ß-Hydroxyphosphonate Analogue of ʟ-Carnitine on Insulin-Sensitive and Insulin-Resistant 3T3-L1 Adipocytes.

This study investigated the effect of a ß-x200B;hydroxyphosphonate analog of ʟ-carnitine (L-CA) (CAS number: 1220955-x200B;20-3, Component: 1221068-91-2, C12H29NO4PI), (3-Hexanaminium, 1-(dimethoxyphosphinyl)-2-hydroxy-N,N,N,5-x200B;tetramethy-iodide (1:1), (2R, 3S)) on parameters related with type-2 diabetes in an in vitro model. Nontoxic concentrations of L-CA were assayed and compared to commercial ʟ-carnitine effects. L-CA did not affect adipogenesis in normal cells, but an increment of TG accumulation was observed on insulin-resistant adipocytes (80%) when compared with resistant control. L-CA also stimulated glucose analog 2-NBDG uptakes on insulin-resistant adipocytes in a similar way as insulin when compared to insulin-resistant cells. Our results show that the L-CA promoted insulin-like responses on insulin-resistant adipocytes without appreciable pro-adipogenic effect in sensitive adipocytes.

Effectiveness of intra-articular injections of sodium bicarbonate and calcium gluconate in the treatment of osteoarthritis of the knee: a randomized double-blind clinical trial.

BACKGROUND: A novel therapeutic management of osteoarthritis (OA) of the knee was assessed. The study aimed to evaluate the effect of monthly sodium bicarbonate with a single (SBCG1) or double dose (SBCG2) of calcium gluconate injections on OA of the knee; as well as the efficacy and safety of both SBCG interventions in the long term. METHODS: A double-blind parallel-group clinical trial with 74 knee OA patients was performed during 12 months, both SBCG interventions were followed-up for another 6mo after intervention. The outcome variables were the Western Ontario-McMaster University Osteoarthritis Index (WOMAC), the Lequesne's functional index and joint-space width changes from serial radiographs. RESULTS: After 12 months, group SBCG1 decreased -14.8 (95% CI:-14.2, -17.0) and group SBCG2 decreased -14.6 (-16.9, -12.4) in the global WOMAC score, the mean changes represent 80% and 82% lessened pain, respectively. In the Lequesne Functional Index scale, SBCG1 decreased -11.9 (-10.4, -14.2) and SBCG2 decreased -11.9 (-13.8, -10.0), representing 66 and 69% of improvement. Both mean scores were maintained after intervention discontinued. SBCG2 improved the knees' joint space width more than SBCG1 at 3 and 18 months. Both SBCG interventions were well tolerated after 12 months of treatment CONCLUSION: A solution of sodium bicarbonate and calcium gluconate is effective on reducing the symptoms associated with OA. Its beneficial effect is maintained for one year of continuous monthly administration and at least for 6 months after the administration is discontinued. When the dose of calcium gluconate is increased, it prevents further narrowing of joint-space. TRIAL REGISTRATION: Clinicaltrials.gov NCT00977444 September 11, 2009.

Increased calorie intake at a specific mid-morning meal and increased intake of soft drinks are strongly associated with obesity in Mexican rural women.

The study investigated the dietary habits and foods that are associated with obesity in women from a rural area in Mexico. Anthropometry and body fat were measured in 580 women. Participants answered a socioeconomic and a food-frequency questionnaire; a subsample (n = 80) also answered three 24-hour-recall questionnaires. Results showed that obese women consumed more soft drinks and fat than did overweight and normal-weight women. Women who consumed more energy during a mid-morning meal had higher BMI. A strategy to decrease the prevalence of obesity in rural areas could be to encourage limiting the consumption of soft drinks and eliminating or reducing caloric intake at a mid-morning meal.

Dietary Energy Density Is Associated with Biomarkers of Chronic Diseases-A Cross-Sectional Study of School-Aged Children in Rural Mexico.

Background: Dietary energy density (DED) is associated with chronic disease markers in adults. However, results in children are still controversial. Objective: To evaluate the DED of children and its association with obesity and biomarkers of chronic disease. Methods: In this cross-sectional study, we recruited 284 children (6-10 y) from rural Mexico. Dietary intake was assessed using three 24-h recalls. DED was calculated for "foods only" (DEDfo) and for "foods and beverages" (DEDfb). Weight, height, and body fat percent (dual-energy X-ray absorptiometry) were measured. Inflammatory cytokines, lipid profile, leptin, and insulin resistance were determined from a fasting blood sample. Results: DEDfo was 1.91 ± 0.36 kcal/g and DEDfb was 1.36 ± 0.31 kcal/g. Higher DEDfo and DEDfb were associated with higher risk to have insulin resistance [odds ratio (OR) = 3.92, 95% confidence interval (CI): 1.66, 9.22, P < 0.01; OR = 3.51, 95% CI: 1.25, 9.87, P = 0.02, respectively]. Higher DEDfo was associated with higher risk of higher leptin levels (OR = 3.17, 95% CI: 1.01, 10.23). Also, DEDfo and DEDfb were associated with higher concentrations of cholesterol (ß = 11.67, 95% CI: 1.81, 19.53, P = 0.03; and ß = 11.74, 95% CI: 2.69, 20.74 P = 0.01, respectively) and higher odds of having high insulin concentrations (OR = 2.52, 95% CI: 1.26, 5.06, P = 0.01; and OR = 2.95, 95% CI: 1.30, 6.70, P = 0.01). DEDfo and DEDfb were not associated with any measure of obesity and inflammatory cytokines in the adjusted models. Conclusions: DED was associated with higher leptin and cholesterol concentrations, and having insulin resistance, but not with any measure of obesity or inflammation. Reducing DED may reduce risk of cardiovascular disease and improve insulin sensitivity in school-aged children.

Specific micronutrient concentrations are associated with inflammatory cytokines in a rural population of Mexican women with a high prevalence of obesity.

It has been recognised recently that obese individuals have lower concentrations of micronutrients and this may affect the concentrations of inflammatory cytokines. A cross-sectional study was carried out to evaluate the association of specific micronutrients' status with chronic inflammation caused by obesity in 280 women (36·1 (SD 7·5) years) from seven rural communities in Mexico. Measurements of weight, height and waist circumference were made on all women and body composition was determined by dual-energy X-ray absorptiometry. Concentrations of the cytokines IL-1, TNF-α, IL-6, IL-10 and IL-12, lipid profile, and the micronutrients Zn and vitamins A, C and E were determined in fasting blood samples. Ordered logistic regression models were used to determine associations between categorised cytokine levels and micronutrients. It was found that 80% of women were overweight or obese, and had significantly higher concentrations of C-reactive protein than normal-weight women (P= 0·05). The risk of higher levels of TNF-α, IL-6, IL-10 and IL-12 was reduced significantly among women with higher Zn concentrations (OR 0·63, 95% CI 0·42, 0·96, P= 0·03; OR 0·57, 95% CI 0·39, 0·86, P= 0·025; OR 0·63, 95% CI 0·41, 0·96, P= 0·04; OR 0·62, 95% CI 0·41, 0·95, P= 0·03, respectively). Higher concentrations of vitamin A were slightly associated with reduced risks of higher levels of IL-1 and IL-12 (OR 0·97, 95% CI 0·95, 0·99, P= 0·03; OR 0·97, 95% CI 0·94, 0·99, P= 0·03, respectively); when adjusting for BMI, this association was lost. No associations were found between vitamin C or vitamin E:lipids concentrations and inflammatory cytokines. In conclusion, higher Zn concentrations are associated with reduced risks of higher concentration of inflammation markers in a population of women with a high prevalence of obesity.

Food insecurity is associated with glycemic markers, and socioeconomic status and low-cost diets are associated with lipid metabolism in Mexican mothers.

The association between socioeconomic status (SES) and chronic disease has recently become more evident in middle- and low-income countries. We hypothesized that poor socioeconomic conditions, such as food insecurity, low educational level, or low SES, may restrict access to a healthy diet and may be associated with cardiometabolic risk independently of body fat. This study examined the relation between socioeconomic indicators, body fat, and cardiometabolic disease risk markers in a random sample of mothers living in Queretaro, Mexico. Young and middle-aged mothers (n = 321) answered validated questionnaires to determine SES, food insecurity, and educational level and a semiquantitative food frequency questionnaire to determine dietary patterns and the cost of individual diet. Clinical measurements included anthropometry, blood pressure, lipids profile, glucose, and insulin. Obesity was present in 29% of the participants. Women with moderate food insecurity had higher waist circumference, glucose, insulin, and homeostasis model assessment of insulin resistance than women with food security. High triglyceride concentration and lower levels of high-density lipoprotein and low-density lipoprotein cholesterol were associated with lower SES and lower educational level. Women who consumed a lower carbohydrate diet had higher SES, higher education, and better cardiovascular risk markers. The higher carbohydrate diet profile was the least expensive diet. There was an inverse association between the cost and energy-density of foods. In conclusion, food insecurity was associated with glycemic control markers, and lower SES and education were related to a low-cost, higher carbohydrate diet and to a greater cardiovascular risk. The influence of the social environment on obesity and cardiovascular diseases needs to be further explored.

Vitamin B-12 supplementation of rural Mexican women changes biochemical vitamin B-12 status indicators but does not affect hematology or a bone turnover marker.

A high prevalence of low serum vitamin B-12 concentrations has been reported in studies and surveys in Latin America including Mexico, but the functional consequences are unknown. This randomized controlled trial assessed the response to a high-dose vitamin B-12 supplementation of women in rural Querétaro, Mexico. Participants aged 20-59 y were stratified at baseline to deficient, marginal, and adequate status groups (serum vitamin B-12, 75-148, 149-220, and >220 pmol/L, respectively), and each group was randomized to vitamin B-12 treatment (single dose of 1 mg i.m. then 500 µg/d orally for 3 mo, n = 70) or placebo (n = 62). Measures at baseline and 3 mo included: complete blood count, serum vitamin B-12, holotranscobalamin (holoTC), folate, ferritin, C-reactive protein (CRP), bone alkaline phosphatase, and methylmalonic acid (MMA) and plasma total homocysteine (tHcy). At baseline, 11% of the women were vitamin B-12 deficient and 22% had marginal status. HoloTC was low (<35 pmol/L) in 23% and correlated with serum vitamin B-12 (r = 0.7; P < 0.001). Elevated MMA (>271 nmol/L) and tHcy (>12 µmol/L) occurred in 21 and 31%, respectively, and correlated with serum vitamin B-12 (r = -0.28, P < 0.0007 and r = -0.20, P < 0.01, respectively). Supplementation increased serum vitamin B-12 and holoTC and lowered MMA and tHcy, normalizing all values except for elevated tHcy in 21% of the women. Supplementation did not affect hematology or bone-specific alkaline phosphatase. Vitamin B-12 supplementation normalized biochemical indicators of vitamin B-12 status in the treatment group but did not affect the functional outcomes measured.

The inclusion of a partial meal replacement with or without inulin to a calorie restricted diet contributes to reach recommended intakes of micronutrients and decrease plasma triglycerides: a randomized clinical trial in obese Mexican women.

BACKGROUND: Obesity is a major public health problem in many poor countries where micronutrient deficiencies are prevalent. A partial meal replacement may be an effective strategy to decrease obesity and increase micronutrient intake in such populations. The objective was to evaluate the efficacy of a partial meal replacement with and without inulin on weight reduction, blood lipids and micronutrients intake in obese Mexican women. METHODS: In a randomized controlled clinical trial 144 women (18-50 y) with BMI ≥ 25 kg/m², were allocated into one of the following treatments during 3 months: 1) Two doses/d of a partial meal replacement (PMR), 2) Two doses/d of PMR with inulin (PMR + I) , 3) Two doses/d of 5 g of inulin (INU) and 4) Control group (CON). All groups received a low calorie diet (LCD). Weight, height, hip and waist circumference were measured every 2 weeks and body composition, lipids and glucose concentration and nutrient intake were assessed at baseline and after 3 months. RESULTS: All groups significantly reduced weight, BMI, waist and hip circumference. Differences between groups were only observed in BMI and weight adjusted changes: At 45 days PMR group lost more weight than INU and CON groups by 0.9 and 1.2Kg, respectively. At 60 days, PMR + I and PMR groups lost more weight than in INU by 0.7 and 1Kg, respectively. Subjects in PMR, PMR + I and INU significantly decreased triglycerides. Energy intake was reduced in all groups. Fiber intake increased in PMR + I and INU groups. Some minerals and vitamins intakes were higher in PMR and PMR + I compared with INU and CON groups. CONCLUSION: Inclusion of PMR with and without inulin to a LCD had no additional effect on weight reduction than a LCD alone but reduced triglycerides and improved intake of micronutrients during caloric restriction. PMR could be a good alternative for obese populations with micronutrient deficiencies.

Bioavailability of zinc oxide added to corn tortilla is similar to that of zinc sulfate and is not affected by simultaneous addition of iron.

BACKGROUND: Corn tortilla is the staple food of Mexico and its fortification with zinc, iron, and other micronutrients is intended to reduce micronutrient deficiencies. However, no studies have been performed to determine the relative amount of zinc absorbed from the fortified product and whether zinc absorption is affected by the simultaneous addition of iron. OBJECTIVE: To compare zinc absorption from corn tortilla fortified with zinc oxide versus zinc sulfate and to determine the effect of simultaneous addition of two doses of iron on zinc bioavailability. METHODS: A randomized, double-blind, crossover design was carried out in two phases. In the first phase, 10 adult women received corn tortillas with either 20 mg/kg of zinc oxide added, 20 mg/kg of zinc sulfate added, or no zinc added. In the second phase, 10 adult women received corn tortilla with 20 mg/kg of zinc oxide added and either with no iron added or with iron added at one of two different levels. Zinc absorption was measured by the stable isotope method. RESULTS: The mean (+/- SEM) fractional zinc absorption from unfortified tortilla, tortilla fortified with zinc oxide, and tortilla fortified with zinc sulfate did not differ among treatments: 0.35 +/- 0.07, 0.36 +/- 0.05, and 0.37 +/- 0.07, respectively. The three treatment groups with 0, 30, and 60 mg/kg of added iron had similar fractional zinc absorption (0.32 +/- 0.04, 0.33 +/- 0.02, and 0.32 +/- 0.05, respectively) and similar amounts of zinc absorbed (4.8 +/- 0.7, 4.5 +/- 0.3, and 4.8 +/- 0.7 mg/day, respectively). CONCLUSIONS: Since zinc oxide is more stable and less expensive and was absorbed equally as well as zinc sulfate, we suggest its use for corn tortilla fortification. Simultaneous addition of zinc and iron to corn tortilla does not modify zinc bioavailability at iron doses of 30 and 60 mg/kg of corn flour.

Vitamin A modifies the intestinal chemokine and cytokine responses to norovirus infection in Mexican children.

Vitamin A supplementation is associated with divergent clinical norovirus (NoV) outcomes in Mexican children. Fecal cytokine concentrations following NoV genogroup infections among 127 Mexican children 5-15 mo old enrolled in a randomized, double-blind, placebo-controlled, vitamin A supplementation trial were determined to clarify the role the gut immune response plays in these associations. Stools collected from supplemented children [20,000 IU retinol (3.3 IU = 1 µg retinol) for children < 12 mo of age; 45,000 iu for children ≥ 12 mo] or children in the placebo group were screened for NoV genogroups I (GI) and II (GII). Monocyte chemoattractant protein-1 (MCP-1), TNFα, IL-5, IL-6, IL-8, IL-4, IFNγ, and IL-10 fecal concentrations were also determined. Differences in cytokine levels between the 2 groups following GI and GII infections were determined using ordered logistic regression models. MCP-1 and IL-8 levels were greater among GI- and GII-infected children, respectively, compared with uninfected children, whereas IL-5 levels were greater following both genogroup infections. MCP-1, IL-8, and IL-6 fecal levels were reduced among supplemented children with GII-associated diarrhea compared with the placebo group. Vitamin A-supplemented, GII-infected children had reduced MCP-1 and TNFα levels compared with GII-infected children in the placebo group (P-interaction = 0.02 and 0.03, respectively). Supplemented children with GI-associated diarrhea had higher TNFα and IL-4 levels compared with children in the placebo group with diarrhea (P-interaction = 0.02 and 0.02, respectively). The divergent effects of supplementation on NoV outcomes may result from the different effects vitamin A has on the genogroup-specific immune responses.