C ucurbita ficifolia Bouché (Cucurbitaceae) and D-chiro-inositol modulate the redox state and inflammation in 3T3-L1 adipocytes

Objectives

Cucurbita ficifolia (characterised by its D chiro inositol (DCI) content) and of synthetic DCI on the redox state, mRNA expression and secretions of proinflammatory cytokines. Additionally, we evaluated the insulin-mimetic action of both treatments by assessing protein kinase B (PKB) activation in 3T3-L1 adipocytes.

Methods

Adipocytes were treated with C. ficifolia and synthetic DCI. The redox state was determined by spectrophotometry as changes in the reduced glutathione/oxidised glutathione (GSH/GSSG) ratio, glutathione peroxidase and glutathione reductase activities; H2O2 levels were measured by flow cytometry. The mRNA expression and the protein level of cytokines were determinate by real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The activation of PKB activation was detected by Western blot.

Key findings

C. ficifolia extract and synthetic DCI reduced oxidative stress by decreased H2O2 levels, increased glutathione peroxidase activity and changes in the GSH/GSSG ratio. Furthermore, DCI decreased the mRNA expression and secretion of tumour necrosis factor-α, interleukin 6 (IL-6) and resistin, while C. ficifolia reduced protein levels of resistin and increased IL-6 levels. Only DCI demonstrated insulin-mimetic action.

Conclusions

The antioxidant and anti-inflammatory effects of C. ficifolia extract can be explained in part by its DCI content, which modulates the GSH/GSSG ratio and contributes to a reduced proinflammatory state. C. ficifolia and DCI treatments may reduce the disturbances caused by oxidative stress. Additionally, DCI may improve insulin sensitivity through its insulin-mimetic effects.

Quality of services and quality of life from service providers' perspectives: analysis with focus groups

BACKGROUND

Concepts such as support, quality of life and quality of services are customary in services for people with intellectual disabilities. The identification of the different ways of conceiving, prioritising and implementing these concepts by service providers can help to drive changes to achieve better personal outcomes for this population. The current study aims to identify service providers' perceptions regarding the quality of life of their clients and the quality of services they provide. It also aims to identify similarities and differences of appraisals among professionals, and to identify associations between supports, quality of life and quality of services.

METHOD

Data were collected from 22 service providers who attended three focus groups (professionals, direct support staff, and managers) from whom 424 comments were analysed. Service providers were asked about the required support for users, the meaning of quality of life for those users, and about features that should characterise quality services. Thematic analysis was employed and transcripts of the sessions were coded according to the dimensions of models on supports, quality of life and quality of services. Chi-squared tests were utilised to test for potential differences among groups.

RESULTS

Each professional group has its own priorities concerning required supports. Among the organisation different and potentially conflicting perceptions regarding the meaning of experiencing quality of life coexist. Concerning quality of services, only managers mentioned personal outcomes. Finally, institutionalisation has a negative impact on supports, quality of life and quality of services.

CONCLUSIONS

It is necessary to move beyond a shared awareness of the negative impact of institutionalisation towards the transformation of services in search of personal quality outcomes.

High glucose induces mitochondrial p53 phosphorylation by p38 MAPK in pancreatic RINm5F cells

Pancreatic β-cell death in type 2 diabetes has been related to p53 subcellular localisation and phosphorylation. However, the mechanisms by which p53 is phosphorylated and its activation in response to oxidative stress remain poorly understood. Therefore, the aim of this study was to investigate mitochondrial p53 phosphorylation, its subcellular localisation and its relationship with apoptotic induction in RINm5F cells cultured under high glucose conditions. Our results show that p53 phosphorylation in the mitochondrial fraction was greater at ser392 than at ser15. This increased phosphorylation correlated with an increase in reactive oxygen species, a decrease in the Bcl-2/Bax ratio, a release of cytochrome c and an increase in the rate of apoptosis. We also observed a decline in ERK 1/2 phosphorylation over time, which is an indicator of cell proliferation. To identify the kinase responsible for phosphorylating p53, p38 mitogen-activated protein kinase (MAPK) activation was analysed. We found that high glucose induced an increase in p38 MAPK phosphorylation in the mitochondria after 24-72 h. Moreover, the phosphorylation of p53 (ser392) by p38 MAPK in mitochondria was confirmed by colocalisation studies with confocal microscopy. The addition of a specific p38 MAPK inhibitor (SB203580) to the culture medium during high glucose treatment blocked p53 mobilisation to the mitochondria and phosphorylation; thus, the release of cytochrome c and the apoptosis rate in RINm5F cells decreased. These results suggest that mitochondrial p53 phosphorylation by p38 MAPK plays an important role in RINm5F cell death under high glucose conditions.

Allele frequency distribution of CYP2C9 2 and CYP2C9 3 polymorphisms in six Mexican populations

Allele frequency differences of functional CYP2C9 polymorphisms are responsible for some of the variation in drug response observed in human populations. The most relevant CYP2C9 functional variants are CYP2C9*2 (rs1799853) and CYP2C9 3 (rs1057910). These polymorphisms show variation in allele frequencies among different population groups. The present study aimed to analyze these polymorphisms in 947 Mexican-Mestizo from Mexico City and 483 individuals from five indigenous Mexican populations: Nahua, Teenek, Tarahumara, Purepecha and Huichol. The CYP2C9*2 allele frequencies in the Mestizo, Nahua and Teenek populations were 0.051, 0.007 and 0.005, respectively. As for CYP2C9 3, the allelic frequencies in the Mestizo, Nahua and Teenek populations were 0.04, 0.005 and 0.005, respectively. The CYP2C9 2 and CYP2C9 3 alleles were not observed in the Tarahumara, Purepecha and Huichol populations. These findings are in agreement with previous studies reporting very low allele frequencies for these polymorphisms in American Indigenous populations.

Analysis of the contribution of FTO, NPC1, ENPP1, NEGR1, GNPDA2 and MC4R genes to obesity in Mexican children

Background

Recent genome wide association studies (GWAS) and previous positional linkage studies have identified more than 50 single nucleotide polymorphisms (SNPs) associated with obesity, mostly in Europeans. We aimed to assess the contribution of some of these SNPs to obesity risk and to the variation of related metabolic traits, in Mexican children.

Methods

The association of six European obesity-related SNPs in or near FTO, NPC1, ENPP1, NEGR1, GNPDA2 and MC4R genes with risk of obesity was tested in 1,463 school-aged Mexican children (N_cases = 514; N_controls = 949). We also assessed effects of these SNPs on the variation of body mass index (BMI), fasting serum insulin levels, fasting plasma glucose levels, total cholesterol and triglyceride levels, in a subset of 1,171 nonobese Mexican children.

Results

We found a significant effect of GNPDA2 rs10938397 on risk of obesity (odds ratio [OR] = 1.30; P = 1.34 × 10^-3). Furthermore, we found nominal associations between obesity risk or BMI variation and the following SNPs: ENPP1 rs7754561, MC4R rs17782313 and NEGR1 rs2815752. Importantly, the at-risk alleles of both MC4R rs17782313 and NPC1 rs1805081 showed significant effect on increased fasting glucose levels (β = 0.36 mmol/L; P = 1.47 × 10^-3) and decreased fasting serum insulin levels (β = −0.10 μU/mL; P = 1.21 × 10^-3), respectively.

Conclusion

Our present results suggest that some obesity-associated SNPs previously reported in Europeans also associate with risk of obesity, or metabolic quantitative traits, in Mexican children. Importantly, we found new associations between MC4R and fasting glucose levels, and between NPC1 and fasting insulin levels.

Profile of patients admitted with infected skin ulcers at Bella Vista Hospital Mayagüez

The purpose of this study is to evaluate the characteristics of patients admitted to Bella Vista Hospital in Mayagüez with a diagnosis of infected skin ulcer, the most common microorganisms recovered in cultures, and their antimicrobial sensitivity patterns.

METHODS

All patients discharged with the diagnosis of infected skin ulcer from January 1 through December 31, 2012 were selected. Following variables were extracted: sex, age, hospital stay, morbid conditions, antibiotics used, microorganisms identified on cultures and sensitivity of microorganisms to different antimicrobials. Prevalence rates were estimated for different conditions and different microorganisms. The use of empirical antibiotics were described and compared with the antimicrobial sensitivity of the microorganisms.

RESULTS

The study population consisted of 98 subjects (54% female, 46% male). Mean age was 71 years old, with 71% of subjects older than 65 years old. Prevalence rates of diabetes mellitus, peripheral vascular disease, hypertension and osteomyelitis were 74.5%, 74.5%, 79.6%, and 17.5% respectively. The antibiotic most frequently used was piperacyllin-tazobactam (PTZ). The organisms most frequently found on cultures were Staphylococcus (37.8%), distributed as 20.4% methicillin resistant and 17.3 sensitive to methicillin, followed by E. coli (30.6%), Streptococcus (29.6%), and Pseudomonas (27.6%). The majority of microorganisms were sensitive to PTZ. There was a higher prevalence of osteomyelitis in diabetic patients than in non-diabetic patients but the difference was not statistically significant.

CONCLUSIONS

Antibiotic sensitivity patterns were consistent with the expected, according to the literature. Empirically used antibiotics were appropriate according to sensitivity patterns shown in the study.

Abstract P4-02-03: FDG PET/CT for early monitoring of response to neoadjuvant chemotherapy in breast cancer patients

Introduction: Neoadjuvant chemotherapy (NAC), initially used only for locally advanced breast cancer, is now commonly used in patients with operable but large breast cancer or unfavorable tumor/breast size index because increases the chances of performing breast conservative surgery (BCS) instead of mastectomy in this group of patients.

Patients and Methods: This is a prospective unicenter trial. FDG PET/CT were performed in 40 patients at baseline and after the second cycle of NAC. The level and relative changes in standardized uptake value (SUV) of FDG uptake were assessed regarding their ability to predict histopathologic response.

Pathologic complete response (pCR) was defined as no malignant cells (no invasive ductal carcinoma and no ductal carcinoma in situ) identifiable in sections from the site of the tumor in the breast and in the axillary lymph node.

Results: This prospectively study analyzed forty patients undergoing NAC, all female, age ranged 27–64 years (mean 41.0 years and median 38 years), all tumors were invasive ductal carcinoma, histological tumor grade 1, 2 and 3 were present respectively at 5%, 38.5% and 100% of the sample and nuclear grade 2 and 3 were present respectively at 12.5% and 87.5%. Estrogen receptor was positive in 60% of patients and the progesterone receptor was positive in 47.5% of patients. Her 2 was overexpressed in 12 patients (30%). Phenotype in this sample had the following distribution: 12.5% luminal A (5 patients), 50% Luminal B (20 patients: 14 patients with Ki-67> 14% and 6 cases with HER 2 overexpression), 15 % HER 2 (6 patients) and cases triple negative 9 (22.5%). size of the primary tumor ranged from 4.10 cm to 12.0 cm (mean 7.10 cm). The size of the primary tumor ranged from had a mean of 6.7 cm and a median of 6.0 cm. This group showed great uniformity in relation to primary chemotherapy. NAC with cyclophosphamide and adriamycin were administered to 38 patients. In this study, pCR was obtained in 12 patients (30%). Baseline FDG SUV referring to pCR group was 11.26 and 7.26 in non-pCR group (p = 0.04). FDG SUV after second cycle was 2.73 in pCR group and 4.64 in non-pCR group (p = 0.048). When analyzing ΔSUV (difference between baseline SUV and SUV after second cycle), pCR group had a mean reduction of 81.58% and non-pCR group had a mean reduction of 81.58% (p = 0.001). Receiver operating curve analyses were performed to deter mine optimal differentiation cut-off values of ΔSUV for differentiation of pCR and non-pCR. After two courses of NAC the optimal cutoff value to early differentiation between pCR from non-pCR were 59,1% in decrease of SUV. The sensitivity and specificity were 64,3% and 100,0%, respectively.

Conclusion: The optimum role of FDG PET in predicting the response of breast cancers to neoadjuvant chemotherapy is still not clearly defined and the SUV cut-off needs to be validated. FDG-PET allows for prediction of treatment response by the level of FDG uptake in terms of SUV at baseline and after two cycles of chemotherapy and FDG-PET may be helpful for individual treatment stratification in breast cancer patients.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-02-03.

The SNP at -592 of human IL-10 gene is associated with serum IL-10 levels and increased risk for human papillomavirus cervical lesion development

BACKGROUND

Women with Human Papilloma Virus (HPV) persistence are characterized by high levels of IL-10 at cervix. We have determined whether polymorphisms of IL-10 gene promoter might be associated with increased risk of squamous intraepithelial cervical lesions (SICL) and whether exist significative differences of IL-10 mRNA expression at cervix and systemic and serum IL-10 protein between SICL cases and non-Cervical Lesions (NCL).

METHODS

Peripheral blood samples from SICL (n = 204) and NCL (n = 166) were used to detect IL-10 promoter polymorphisms at loci -592A/C (rs1800872), -819C/T (rs1800871), -1082A/G (rs1800896), -1352A/G (rs1800893), by allelic discrimination and to evaluate serum IL-10 protein. Cervical epithelial scrapings from NCL and biopsies from SICLs were used for HPV-typing and to evaluate IL-10 mRNA expression level. The systemic and local IL-10 mRNA expression levels were measured by real time-PCR. Genotypic and allelic frequencies of the selected polymorphisms were analyzed by logistic regression, adjusting by age and HPV-genotype, to determine the association with SICL.

RESULTS

No significant differences were found between genotype frequencies at loci -819, -1082, and -1352. Individuals carrying at least one copy of risk allele A of polymorphism -592 had a two-fold increased risk of developing SICL [adjusted odds ratio (OR), 2.02 (95% CI, 1.26-3.25), p = 0.003], compared to NCL. The IL-10 mRNA expression and serum IL-10 protein, were significantly higher in SICL cases (p < 0.01), being higher in patients carrying the risk allele A.

CONCLUSIONS

The -592 polymorphism is associated with increased risk of SICL and can serve as a marker of genetic susceptibility to SICL among Mexican women. According to IL-10 levels found in SICL, IL-10 can be relevant factor for viral persistence and progression disease.

Effect of an aqueous extract of Cucurbita ficifolia Bouché on the glutathione redox cycle in mice with STZ-induced diabetes

ETHNOPHARMACOLOGICAL IMPORTANCE

Cucurbita ficifolia is used in Mexican traditional medicine as an anti-diabetic and anti-inflammatory agent and its actions can be mediated by antioxidant mechanisms. Disturbance in the homeostasis of glutathione has been implicated in the etiology and progression of diabetes mellitus and its complications.

MATERIAL AND METHODS

It was evaluated, the effect of an aqueous extract of Cucurbita ficifolia on glycemia, plasma lipid peroxidation; as well as levels of reduced (GSH) and oxidized (GSSG) glutathione and activities of enzymes involved in glutathione redox cycle: glutathione peroxidase (GPx) and glutathione reductase (GR) in liver, pancreas, kidney and heart homogenates of streptozotocin-induced diabetic mice.

RESULTS

Increased blood glucose and lipid peroxidation, together with decreased of GSH concentration, GSH/GSSG ratio and its redox potential (E(h)), and enhanced activity of GPx and GR in liver, pancreas and kidney were the salient features observed in diabetic mice. Administration of the aqueous extract of Cucurbita ficifolia to diabetic mice for 30 days, used at a dose of 200 mg/kg, resulted in a significant reduction in glycemia, polydipsia, hyperphagia and plasma lipid peroxidation. Moreover, GSH was increased in liver, pancreas and kidney, and GSSG was reduced in liver, pancreas and heart, therefore GSH/GSSG ratio and its E(h) were restored. Also, the activities involved in the glutathione cycle were decreased, reaching similar values to controls.

CONCLUSIONS

An aqueous extract of Cucurbita ficifolia with hypoglycemic action, improve GSH redox state, increasing glutathione pool, GSH, GSH/GSSG ratio and its E(h), mechanism that can explain, at least in part, its antioxidant properties, supporting its use as an alternative treatment for the control of diabetes mellitus, and prevent the induction of complications by oxidative stress.

Metformin decreases plasma resistin concentrations in pediatric patients with impaired glucose tolerance: a placebo-controlled randomized clinical trial

The objective was to determine the effect of metformin on the concentrations of resistin and other markers of insulin resistance or inflammation (C-reactive protein, cytokines, body weight, HbA1c, among others) in minors with glucose intolerance. Patients aged 4 to 17 years with glucose intolerance were studied. They were randomized to receive 850 mg of either metformin or placebo twice daily for 12 weeks, during which all followed an iso-caloric diet and an exercise program. High sensitivity C-reactive protein, TNF-alpha, IL-6, IL1-beta, resistin, leptin, adiponectin, glucose, insulin, HbA1c, lipid profile and transaminases were measured at the beginning and at the end of the period. Fifty-two patients were included, 11.9±2.6 years old; 28 (12 males/16 females) received metformin and 24 placebo (11 males/13 females). Baseline characteristics were similar between groups (except for body mass index, which in the metformin group was slightly higher). Percentage weight loss was greater in the metformin group (-5.86% vs 2.75%, P<.05). At study end, there were statistically significant differences in resistin concentrations, even after adjusting for confounding variables (F=7.714; P<.006). Also, metformin was associated with a significant decrease in HOMA-IR index (P=.032) and HbA1c levels (P=.001), but no change was observed in the concentration of other markers of inflammation. Metformin resulted in significant reductions of plasma resistin levels in minors with glucose intolerance. This change is independent of its effects on body weight. In contrast, metformin did not alter the concentration of inflammatory markers.

Common variants in the CRP gene are associated with serum C-reactive protein levels and body mass index in healthy individuals in Mexico

Variants in the C-reactive protein (CRP) gene have been found to be associated with various phenotypic traits. We evaluated the effect of four SNPs in the CRP gene on serum levels of protein and body mass index (BMI) in 150 unrelated Mexican subjects from 18 to 25 years old, without hypertension, non-overweight, and without inflammatory diseases, non-smoking and non-consumers of alcohol. Subjects were measured for BMI, waist circumference, blood pressure, and serum glucose and triglycerides. The identification of SNPs was performed by PCR-RFLP. Three of the four SNPs were associated with variation in serum levels of CRP, increased in TT (rs1130864) and GG (rs2794521) genotypes, and decreased in the AA genotype of rs1205. The TT genotype was associated with a significant increase in BMI (β = 1.1 kg/m², P = 0.04). Two haplotypes were significantly associated with increased serum levels of CRP, but not with BMI. We conclude that variation in the CRP gene affects serum protein levels.

Evaluation of the imputation performance of the program IMPUTE in an admixed sample from Mexico City using several model designs

BACKGROUND

We explored the imputation performance of the program IMPUTE in an admixed sample from Mexico City. The following issues were evaluated: (a) the impact of different reference panels (HapMap vs. 1000 Genomes) on imputation; (b) potential differences in imputation performance between single-step vs. two-step (phasing and imputation) approaches; (c) the effect of different INFO score thresholds on imputation performance and (d) imputation performance in common vs. rare markers.

METHODS

The sample from Mexico City comprised 1,310 individuals genotyped with the Affymetrix 5.0 array. We randomly masked 5% of the markers directly genotyped on chromosome 12 (n=1,046) and compared the imputed genotypes with the microarray genotype calls. Imputation was carried out with the program IMPUTE. The concordance rates between the imputed and observed genotypes were used as a measure of imputation accuracy and the proportion of non-missing genotypes as a measure of imputation efficacy.

RESULTS

The single-step imputation approach produced slightly higher concordance rates than the two-step strategy (99.1% vs. 98.4% when using the HapMap phase II combined panel), but at the expense of a lower proportion of non-missing genotypes (85.5% vs. 90.1%). The 1,000 Genomes reference sample produced similar concordance rates to the HapMap phase II panel (98.4% for both datasets, using the two-step strategy). However, the 1000 Genomes reference sample increased substantially the proportion of non-missing genotypes (94.7% vs. 90.1%). Rare variants (<1%) had lower imputation accuracy and efficacy than common markers.

CONCLUSIONS

The program IMPUTE had an excellent imputation performance for common alleles in an admixed sample from Mexico City, which has primarily Native American (62%) and European (33%) contributions. Genotype concordances were higher than 98.4% using all the imputation strategies, in spite of the fact that no Native American samples are present in the HapMap and 1000 Genomes reference panels. The best balance of imputation accuracy and efficiency was obtained with the 1,000 Genomes panel. Rare variants were not captured effectively by any of the available panels, emphasizing the need to be cautious in the interpretation of association results for imputed rare variants.

rs12255372 variant of TCF7L2 gene is protective for obesity in Mexican children

BACKGROUND AND AIMS

Variants in the transcription factor 7-like 2 (TCF7L2) gene are consistently associated with type 2 diabetes in adults, but the association of TCF7L2 with weight-related traits and body fat in humans is unclear. The aim of this study was to determine the relationship between the TCF7L2 gene (rs12255372) and obese phenotype in Mexican school-age children.

METHODS

The study was performed in schools in Mexico City; 186 obese and 194 control children were studied. Fasting insulin and glucose, total cholesterol, LDL-C, HDL-C and triglycerides concentration were determined. The variant rs12255372 of the TCF7L2 gene was genotyped. We used age- and sex-adjusted linear models to test for association with metabolic measurements with this variant.

RESULTS

Genotype of the TCF7L2 rs12255372 gene was associated with lower fasting plasma glucose (p = 0.001) and lower homeostasis model assessment of insulin resistance (HOMA-R; p = 0.001) in nonobese children. Heterozygous carriers for this variant were more prevalent in lean children (32.5%) than in the obese group (23.7%), which resulted in a strong protective effect for the normal weight condition (OR = 0.56, 0.32-0.97).

CONCLUSIONS

TCF7L2 rs12255372 polymorphism protects Mexican children from obesity. Further research in other large, population-based studies is needed to replicate these findings.

Development of a panel of genome-wide ancestry informative markers to study admixture throughout the Americas

Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs) optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS) data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R²>0.9 for ancestral components with significant between-subject variance). Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region.

Individuals from Latin America are descendants of multiple ancestral populations, primarily Native American, European, and African ancestors. The relative proportions of these ancestries can be estimated using genetic markers, known as ancestry informative markers (AIMs), whose allele frequency varies between the ancestral groups. Once determined, these ancestral proportions can be correlated with normal phenotypes, can be associated with disease, can be used to control for confounding due to population stratification, or can inform on the history of admixture in a population. In this study, we identified a panel of AIMs relevant to Latin American populations, validated the panel by comparing estimates of ancestry using the panel to ancestry determined from genome-wide data, and tested the panel in a diverse set of populations from the Americas. The panel of AIMs produces ancestry estimates that are highly accurate and appropriately controlled for population stratification, and it was used to genotype 18 populations from throughout Latin America. We have made the panel of AIMs available to any researcher interested in estimating ancestral proportions for populations from the Americas.

[The role of innate immunity in obesity]

Obesity in Mexico is alarmingly increasing in prevalence in adults and children, and it is a risk factor for the development of insulin resistance, as well as, of other metabolic alterations. The discovery of the expression of the Toll-like receptors (TLRs) in adipocytes, suggests an important role in innate immunity. In different models of obesity, there has been observed an increase of TLRs expression in the fat tissue, therefore TLRs could be involved in systemic inflammation in this disease, and in the development of insulin resistance. TLR activation is mediated by fatty acids and their expression is regulated by leptin, adiponectin and PPARs. Knowledge of the role of TLRs in inflammation and adipocyte differentiation and their regulation, then it is important to try to develop new therapeutic anti-inflammatory targets that contribute in the treatment of obesity.