Testing for Protein Leverage in Patients with Gastric Bypass: A Pilot Study.

INTRODUCTION: Protein leverage (PL) is the phenomenon whereby a dominant appetite for protein drives overconsumption of energy with a decline in the ratio of protein to fat and carbohydrate in the diet. PL has been independently verified in several randomized control trials, and its predictions are supported by diet surveillance data. Our aim in the present study was to test whether surgical intervention through gastric bypass will ameliorate the PL effect. METHODS: Ten patients with gastric bypass (2-5 years postsurgical time) were given ad libitum access to study food comprising 10%, 15%, or 25% protein and no access to other foods for 3 days while controlling food palatability and variety. Food intake was measured, and energy and nutrient intakes were calculated. Body weight, blood chemistry, lipid profile, hormones (insulin, leptin, and ghrelin), and creatinine were determined before and after each experimental period. RESULTS: The gastric bypass patients in our study did not show evidence for protein intake regulation as predicted under PL but ate to constant total energy intake on the 10%, 15%, and 25% protein diets with protein intake varying significantly. Patients lost weight in the three study periods, but significant weight loss was observed only on the 15% protein diet. CONCLUSION: Our results suggest that gastric bypass might disengage the PL mechanism, thus ameliorating an appetite-specific mechanism that drives energy overconsumption in modern food environments.

Profile of urinary exosomal microRNAs and their contribution to diabetic kidney disease through a predictive classification model.

AIM: Evaluate the expression of exomiRs-126, -146, and -155 in urinary exosomes of patients with T2DM and diabetic kidney disease to establish a predictive classification model with exomiRs and clinical variables in order to determine their contribution to DKD. METHODS: The study group included 92 subjects: 64 patients diagnosed with T2DM subclassified into two groups with albuminuria (T2DM with albuminuria, n = 30) and without albuminuria (TD2M, n = 34) as well as 28 healthy, non-diabetic participants. Exosomes were isolated from urine and identified by TEM and flow cytometry. Profile expression of exomiRs-126, -146 and -155 was evaluated by RT-qPCR. Data were analysed by permutational multivariate analysis of variance (PERMANOVA), similarity percentage (SIMPER), principal coordinate analysis (PCO), and canonical analysis of principal coordinates (CAP). RESULTS: T2DM patients with and without albuminuria showed higher levels of miR-155 and miR-146 compared with controls. In addition, T2DM patients with albuminuria presented a significant increase in miR-126 contrasted to controls and patients without albuminuria. PCO analysis explained 34.6% of the total variability of the data (PERMANOVA; p < .0001). Subsequently, SIMPER analysis showed that miR-146, miR-155, and miR-126 together, with some clinical parameters, contributed to 50% of the between-group significance. Finally, the CAP analysis developed showed a correct classification of 89.01% with the analysed parameters. CONCLUSION: A platform using a combination of clinical variables and exomiRs could be used to classify individuals with T2D as risk for developing DKD.

Possible role of n-hexane as an endocrine disruptor in occupationally exposed women at reproductive age.

Human exposure to n-hexane has been associated with subfertility and, experimentally, with a decrease in follicular development. In order to assess occupational exposure to n-hexane on ovarian function and gonadotropic hormones, we studied Mexican women labouring in a leather shoe factory (n = 34). Individual environmental levels for seven solvents, n-hexane included, were measured; also, urinary 2,5-hexanedione (2,5-HD) was determined. For ovarian function and hormonal status, FSH, LH, oestradiol and anti-Müllerian hormone (AMH) levels were determined. We performed all determinations also in a reference group, administrative workers with no exposure to solvents (n = 32). Results: N-hexane and urinary 2,5-HD levels were higher in exposed group (p < 0.001). More cases of oligomenorrhea as well as longer time for getting pregnant were observed in exposed women compared with controls; a positive association was found between menstrual cycle length and "time for getting pregnant" (p = 0.010); significant associations between FSH serum levels and 2,5-HD urinary levels (post-shift sample) were observed in non-smokers participants presenting oligomenorrhea from exposed group. Also, we found a trend for lower oestradiol levels in exposed participants with current smoking habit (p = 0.059). Conclusions: 2,5-HD urinary levels are associated with decreased gonadotropins levels; hence, n-hexane should be considered an endocrine disruptor in reproductive-age women.

Obesity is associated with the Arg389Gly ADRB1 but not with the Trp64Arg ADRB3 polymorphism in children from San Luis PotosÍ and León, México.

This research was designed to analyze the possible associations of Arg389Gly ADRB1 and Trp64Arg ADRB3 polymorphisms in children with obesity. A cross-sectional study included 1,046 school-age Mexican participants (6-12 years old) from the cities of San Luis PotosÍ and León. Children were classified as non-obese or obese according to their body mass index (BMI) percentile; obese children had a BMI≥95th percentile for sex and age. Biochemical data were collected. Polymorphisms were detected using TaqMan qPCR assay. A logistic regression analysis was used to calculate the risk of obesity based on genotypes. Differences were found between groups where obese children had a significant increase in systolic and diastolic blood pressure, fasting plasma glucose, insulin, HOMA-IR, LDL-cholesterol, triglycerides, and lower HDL-cholesterol compared with the normal weight group (P<0.05). The distribution of allele frequency in the population was Arg= 87.4 and Gly= 12.6 (Hardy Weinberg equilibrium c2 = 3.16 , P = 0.07 ); Trp= 81.5 and Arg= 18.5 (Hardy Weinberg equilibrium c2 = 2.2, P = 0.14 ) for ADRB1 and ADRB3, respectively. Even though no different frequencies of Arg389Gly polymorphism between groups were found (P = 0.08), children carriers of one Gly389 ADRB1 allele had a risk for obesity of OR=1.40 (95%CI, 1.03-1.90, P = 0.03) after adjustment for age and gender. No other association was found for Trp64Arg ADRB3 polymorphism. Only the Arg389Gly ADRB1 polymorphism was associated with risk for obesity in Mexican children.

Dietary advanced glycation end products restriction diminishes inflammation markers and oxidative stress in patients with type 2 diabetes mellitus.

The augmented consumption of dietary advanced glycation end products (dAGEs) has been associated with increased oxidative stress and inflammation, however, there is insufficient information over the effect on insulin resistance. The objective of the present study is to investigate the effect of dAGEs restriction on tumor necrosis factor-α (TNF-α), malondialdehyde, C-reactive protein (CRP), and insulin resistance in DM2 patients. We carried out a randomized 6 weeks prospective study in two groups of patients: subjects with a standard diet (n = 13), vs low dAGEs (n = 13). At the beginning and the end of study, we collected anthropometric measurements, and values of circulating glucose, HbA1c, lipids, insulin, serum AGEs, CRP, TNF-α and malondialdehyde. Anthropometric measurements, glucose, and lipids were similar in both groups at base line and at the end of the study. Estimation of basal dAGEs was similar in both groups; after 6 weeks it was unchanged in the standard group but in the low dAGEs group decreased by 44% (p<0.0002). Changes in TNF-α levels were different under standard diet (12.5 ± 14.7) as compared with low dAGEs (-18.36 ± 17.1, p<0.00001); changes in malondialdehyde were different in the respective groups (2.0 ± 2.61 and -0.83 ± 2.0, p<0.005) no changes were found for insulin levels or HOMA-IR. In conclusion, The dAGEs restriction decreased significantly TNF-α and malondialdehyde levels.

Symptoms at postmenopause: genetic and psychosocial factors.

OBJECTIVE: Menopause symptoms result from the interaction of estrogen deprivation, psychosocial influences, and genetic factors. We examined the influence of stress and of estrogen receptor-α (ER-α; PvuII and XbaI) and serotonin transporter (5-HTT) polymorphisms on symptoms at postmenopause. METHODS: We studied 290 urban women from three cities in Mexico. General characteristics, menopause symptoms, and scores of perceived stress, effort-reward imbalance, dominance, and submission were collected. A fasting blood sample was obtained for hormone measurements and genotypification. RESULTS: Women had a mean ± SD age of 54.4 ± 4.5 years and BMI of 29.5 ± 4.9 kg/m. The frequency of hot flashes was 75.5%; vaginal dryness, 57.8%; and diminished sexual interest, 78.7%. Follicle-stimulating hormone and estradiol levels were 59 ± 27 mIU/mL and 22 ± 29 pg/mL, respectively. Women from Torreón had higher schooling and less parity but higher scores for depression and lower submission. Hot flashes were more frequent in women from León. Genotype distribution was similar among cities. Lower scores for dominance were found in women with the pp and xx ER-α genotypes. Increased smoking habit was found for the SS genotype of 5-HTT. Factors significantly associated with symptoms were years since menopause, with hot flashes (negative), and with diminished sexual interest (positive); dominance was negatively associated with depression, perceived stress, and vaginal dryness; submission was positively associated with depression, perceived stress, anxiety, and hot flashes; and effort-reward imbalance was positively associated with anxiety, hot flashes, and perceived stress. CONCLUSIONS: Symptoms at postmenopause were associated mainly with dominance, submission, and effort-reward imbalance. The pp genotype of ER-α showed lower scores of dominance.

Effect of recreational physical activity on insulin levels in Mexican/Hispanic children.

The effect of increased recreational physical activity in children on insulin levels has not yet been studied. We carried out a randomized controlled trial in 76 children 6-9 years old, 32 of them increased their physical activity and 30 maintained the same level. In the intervention group, after a week of baseline, recreational activity three times/week was programmed for 12 weeks. We compared insulin, homeostatic model assessment (HOMA) index, glucose, HDL-C, LDL-C, triglycerides, and body mass index in both groups. Thereafter, we compared groups of normal weight, overweight, and with obesity in the experimental group. The group of recreational activity increased their median daily steps (15,329 to 19,910) and decreased insulin (p < 0.001) and HOMA index (4.36 vs. 2.39, p < 0.001). The diminution of insulin levels was more significant in the overweight group (p < 0.007). In conclusion, in our group, children who increased physical activity during 12 weeks decrease insulin levels and insulin resistance without change in other metabolic and anthropometric variables.

Prediabetes in rural and urban children in 3 states in Mexico.

The authors studied the frequency, distribution, and factors associated with prediabetes (fasting glucose, 100-125 mg/dL) in rural and urban children from San Luis Potosí, León, and Querétaro in central Mexico. Family history, somatometry, and levels of fasting insulin, glucose, and lipids were collected in 1238 children 6 to 13 years of age. The authors found no cases of type 2 diabetes and a 5.7% frequency of prediabetes. The group with prediabetes had higher homeostasis model assessment of insulin resistance scores and total cholesterol and high-density lipoprotein cholesterol levels. Prediabetes was more frequent in León, with similar distribution in rural and urban children. The frequency of insulin resistance was 24.1%, with higher figures in urban groups and in San Luis Potosí. In multivariate analysis, prediabetes was associated with insulin resistance and residence in León. The authors concluded that in central Mexico the frequency of prediabetes is significant, and it is associated with insulin resistance and a geographic location, but not with obesity or urban vs rural dwelling.

Catch-up growth in infants born small for gestational age--a longitudinal study.

BACKGROUND: Epidemiological studies correlate low birth weight and the subsequent development of diabetes mellitus (DM). Early changes in insulin resistance in infants with catch-up growth (CUG) have not been evaluated in our population. AIM: To identify dietary and metabolic features associated with CUG in infants born small for gestational age (SGA) at 1 year old. METHODS: In a cohort study of 88 term infants (44 SGA and 44 appropriate for gestational age [AGA]), breastfeeding and weaning age were registered. Anthropometric measurements, glucose, insulin, and leptin concentrations were measured at birth and at 1 year old. RESULTS: A history of DM in a second-degree relative (p = 0.01) and complementary breastfeeding (p = 0.0003) were higher in SGA compared to AGA infants. Ten (13.6%) infants showed CUG in length and weight combined. They had lower weight, glucose, IR index, and leptin concentrations at birth than those without CUG. After logistic regression analysis for factors related to weight CUG, gender, weaning age, birth weight and leptin concentration at birth were included in the model (R2 = 0.31; p = 0.00004). CONCLUSIONS: Female gender, early weaning, lower birth weight, and lower leptin concentration at birth are related to weight CUG in Mexican infants.

Hormone and metabolic factors associated with leptin mRNA expression in pre- and postmenopausal women.

Recent information has extended leptin's action, beyond the control of appetite, to various sites of metabolic regulation. To better understand leptin's role we studied its production in subcutaneous and visceral fat compartments before and after menopause. During elective abdominal surgery, biopsies of subcutaneous and omental tissues were taken from 20 women at pre- (BMI 28.4 +/- 4.5 kg/m2) and 10 at postmenopause (BMI 30.6 +/- 7.7 kg/m2). In both groups serum leptin levels were similar, and highly correlated with BMI. In subcutaneous adipose tissue, leptin mRNA expression was significantly higher in pre- than in postmenopausal women (50.4 +/- 20.5 amol/microg total RNA versus 34.5 +/- 24.9 amol/microg total RNA, respectively). Leptin mRNA expression in subcutaneous tissue was independently correlated with fasting glucose (R = 0.89, P < 0.006) at premenopause, and with serum estradiol (R = 0.77, P < 0.04) at postmenopause. Leptin mRNA expression in visceral fat was correlated with DHEAS (R = 0.86, P < 0.001), at premenopause. These results indicate that in both compartments, leptin production is sensitive to different but overlapping stimuli, conveying information about energy availability to central and peripheral sites under different conditions of estrogen exposure.

Effect of alendronate on periodontal disease in postmenopausal women: a randomized placebo-controlled trial.

BACKGROUND: We investigated the effect of oral alendronate (ALN) treatment on radiological and clinical measurements of periodontal disease in postmenopausal women without hormone replacement therapy. METHODS: We evaluated the effect of 6 months of ALN treatment in 40 postmenopausal women, 55 to 65 years old with established periodontal disease, in a controlled, double-masked, prospective study. Volunteers were paired by age and randomized to receive ALN (10 mg/day) or placebo for the study period. Periodontal mechanical treatment was carried out in both groups. At baseline and after treatment, clinical evaluation, hormone blood levels, distance from the crestal alveolar bone (CAB) to the cemento-enamel junction (CEJ), calcaneus bone mineral density (BMD), hormone levels, serum N-telopeptide (NTx), and bone-specific alkaline phosphatase (BSAP) were assessed. RESULTS: Periodontal disease conditions improved in both groups, but greater improvement in probing depth (-0.8 +/- 0.3 mm versus -0.4 +/- 0.4 mm, P = 0.02) and gingival bleeding (-0.3% +/- 0.13% versus -0.2% +/- 0.06%, P = 0.006) was found in the ALN treated group. Calcaneus BMD increased in the ALN treated group (68 +/- 47 mm3 versus -26 +/- 81 mm3, P = 0.0006). CAB-CEJ distance diminished in the ALN group (-0.4 +/- 0.40 mm versus 0.60 +/- 0.53 mm, P = 0.00008). Marginal reduction in both NTx and BSAP levels was found in the ALN group (-9.4 +/- 6.6 nmol versus -4.3 +/- 4.7 nmol bone collagen equivalents, P = 0.08, and -7.7 +/- 8.4 versus -1.5 +/- 5.0 U/l, P = 0.1, respectively). Hormone levels were unchanged after treatment. Similar improvement of calcaneus BMD and CAB-CEJ distance with ALN treatment was found in obese and non-obese women. CONCLUSION: ALN treatment improved periodontal disease and bone turnover in postmenopausal women.