Effect of Inulin Intervention on Metabolic Control and Methylation of INS and IRS1 Genes in Patients with Type 2 Diabetes Mellitus.

BACKGROUND AND AIMS: Currently, treatments are being sought to improve the control of type II diabetes mellitus (T2DM), and inulin has been shown to be effective in reducing glucose levels and other metabolic control parameters. These effects on metabolic control may be associated with changes in the epigenetic modulation of genes of the insulin pathway. Therefore, our objective is to determine the effect of agave inulin in metabolic control parameters and in INS and IRS1 genes' methylation in T2DM patients. METHODS: This was a longitudinal experimental study with 67 Mexican participants who received an intervention of inulin agave (10 g daily) for 2 months. The methylation of the INS and IRS1 genes was determined by MSP. RESULTS: For the INS gene, we found a significant decrease in the proportions of T2DM patients with methylated DNA after inulin intervention (p = 0.0001). In contrast, the difference in the proportions of the unmethylated IRS1 gene before and after the inulin intervention was not significant (p = 0.79). On the other hand, we observed changes in the number of T2DM patients' recommended categories for metabolic control depending on the methylation of INS and IRS1 genes before and after treatment with inulin. CONCLUSION: For the first time, we report the modification in the methylation of two genes, INS and IRS1, of the insulin pathway and provide information on the possible relevant role of epigenetics as a key factor in positive changes in metabolic control parameters by inulin intake in T2DM patients.

Use of Natural Products on the Control of Aspergillus flavus and Production of Aflatoxins In Vitro and on Tomato Fruit.

Aspergillus flavus affects fresh and dry fruit and vegetable products, and its toxic metabolites, namely aflatoxins, cause serious damage in humans. The objective of this research study was to evaluate the effect of commercial natural products as well as edible and nanostructured chitosan coatings on the development of A. flavus and on the production of aflatoxins in vitro and in tomato. Treatments were as follows: chitosan 1%, chitosan coating, chitosan nanostructured coating, Citrocover 1% (citrus seed extract), Resinadher 0.5% (pine resin extract), mancozeb 2%, and water. The variables were as follows: halo inhibition, spore production, and aflatoxins content. In fruit, the following were evaluated: disease incidence, mycelial growth, and aflatoxin production. An ANOVA (Tukey: p < 0.05) was used. In vitro results showed that Citrocover and Resinadher reduced sporulation (0.2 and 0.9 × 105 spores mL-1, respectively), while chitosan inhibited the production of aflatoxins. With Resinadher and Citrocover, tomato fruit had the lowest incidence, mycelial growth, and aflatoxin production with corresponding values of 0%, 0.0 cm2, and 0.95 ppb, respectively, and 7%, 0.2 cm2, and 1.77 ppb, respectively. The use of Citrocover and Resinadher could be a viable alternative to decrease the development of A. flavus in tomato fruit.

Association of the Promoter Methylation and the rs12917 Polymorphism of MGMT with Formation of DNA Bulky Adducts and the Risk of Lung Cancer in Mexican Mestizo Population.

O6-Methylguanine-DNA methyltransferase (MGMT) is an enzyme that repairs the DNA damage caused by the tobacco habit, and low activity of this enzyme has been associated with a risk of lung cancer (LC). Our objective was to determine the association of the promoter methylation and the rs12917 polymorphism of MGMT with formation of DNA bulky adducts and the risk of LC in the Mexican Mestizo population. In this study are included 431 subjects. High-resolution melting analysis was used to determine the polymorphism MGMT rs12917 and methylation levels. DNA bulky adducts were determined by 32P-postlabeling. Our results showed that MGMT rs12917 and higher levels of methylation in the MGMT promoter are associated with the risk of LC. The levels of adducts are related with the phe/phe genotype and, only in the cases group, with the hypermethylation (>50%) of MGMT; however, this last association was not statistically significant.

CHRNA3 rs1051730 and CHRNA5 rs16969968 polymorphisms are associated with heavy smoking, lung cancer, and chronic obstructive pulmonary disease in a mexican population.

BACKGROUND AND PURPOSE: Smoking is a major public health problem worldwide. Polymorphisms in CHRNA3, CHRNA5, and CHRNB4 receptors play a critical role in nicotine dependence, lung cancer (LC) risk, and chronic obstructive pulmonary disease (COPD). This study characterized the CHRNA3 rs1051730 and CHRNA5 rs16969968 polymorphisms in a Mexican population and its association with nicotine dependence, LC, and COPD. METHODS: The study included 312 healthy individuals, 74 LC cases and 117 COPD cases. Genotyping was performed using TaqMan probes, and the data were analyzed using logistic regression adjusted for covariates. RESULTS: The polymorphism CHRNA3 rs1051730 and CHRNA5 rs16969968 were in the Hardy-Weinberg equilibrium and the allelic frequency of the A allele was 0.15, for both polymorphisms. The smokers were stratified in heavy smokers and moderate/light smokers, and we found in A alleles an OR = 2.86 (P = 0.01) to CHRNA3 rs1051730 and OR = 3.12 (P = 0.03) to CHRNA5 rs16969968. In addition, the A alleles in CHRNA3 rs1051730 and CHRNA5 rs16969968 were associated with the risk for LC (OR = 1.66, P = 0.07 and OR = 1.57, P = 0.1, respectively) and for COPD (OR = 2.04, P = 0.01 and OR = 1.91, P = 0.02, respectively). CONCLUSION: CHRNA3/5 polymorphisms are associated with nicotine dependence, LC, and COPD in Mexicans.