Jaime Gomez-Zamudio

SOD2 gene Val16Ala polymorphism is associated with macroalbuminuria in Mexican Type 2 Diabetes patients: a comparative study and meta-analysis

BackgroundSeveral studies in type 2 diabetes patients have shown significant associations between the SOD2 gene Val16Ala polymorphism and albuminuria, but this association has not been explored in the Mexican population.MethodsWe evaluated the association between the SOD2 gene Val16Ala polymorphism (rs4880) and macroalbuminuria in a sample of 994 unrelated Mexican type 2 diabetes patients. The study included 119 subjects with urinary albumin >300 mg/dL and 875 subjects with urinary albumin ≤ 30 mg/dL. Genotyping of the SOD2 gene Val16Ala SNP was carried out with Real-Time Polymerase Chain Reaction (RT-PCR).ResultsThe frequency of the TT genotype was 6.7% higher in participants with macroalbuminuria than in the normoalbuminuria group (16.8% vs. 10.1%). Using a logistic regression analysis, we observed that individuals with the CC genotype had significantly lower risks of macroalbuminuria than those with the TT genotype (OR=0.42, p=0.034). We carried out a meta-analysis combining our data with data from four previous studies and estimated an odds ratio (95% CI) for the C allele (with respect to the reference T allele) of 0.65 (0.52-0.80, p<0.001).ConclusionsA significant association was found between the SOD2 Val16Ala polymorphism and macroalbuminuria in a sample of Mexican type 2 diabetes patients.

Assessing the effects of 35 European-derived BMI-associated SNPs in Mexican children

The prevalence of obesity in Mexico has increased at an alarming rate in both adults and children. This study was undertaken to test in Mexican children the effects of single nucleotide polymorphisms (SNP) that have been associated with body mass index (BMI) and obesity in Europeans.

Antidiabetic, antihyperlipidemic and anti-inflammatory effects of tilianin in streptozotocin-nicotinamide diabetic rats.

Flavonoids from medicinal plants have been used in traditional medicine to treat a variety of prevalent diseases. Flavones activate the signaling pathways promoting fuel metabolism and insulin sensitizing in hepatocytes and adipocytes, which suggests that flavones may have the potential to exert in vivo antidiabetic and antihyperlipidemic effects. Thus, the aim of the current study was to determine the antidiabetic, antihyperlipidemic and anti-inflammatory effects of tilianin in diabetic rats. Also, to understand the mechanism involved using in vitro 3T3-L1 cells and tissues from experimental animals treated with test samples through molecular profile studies. Non insulin-dependent diabetic mellitus (NIDDM) rats were treated over a short period (for 10 days) with 60mg/Kg/day of tilianin. After treatment, a biochemical blood profile was determined. Also, adipose and thoracic aortic tissues were used to determine pro-inflammatory profile, adiponectin and adhesion molecules by real-time PCR. In 3T3-L1 cells pretreated with tilianin (10μM), PPARα, PPARγ, GLUT4, FATP-1 and ACSL-1 mRNA expression were measured. In order to explain the potential PPARα interaction with tilianin, a docking study with PPARα was carried out. Thus, intragastric administration of tilianin and metformin induced a decrease in plasma glucose (GLU) in diabetic rats on day 6, and remained significantly lower until the end of the treatment; also blood triacylglycerides (TAG) and cholesterol (CHOL) (p<0.05) were diminished. Moreover, IL-1β and IL-18 expression was significantly decreased in adipose tissue (p<0.05); meanwhile adiponectin was significantly overexpressed (p<0.05). Besides, ICAM-1 expression was significantly reduced in aortic tissue (p<0.05). In 3T3-L1 cells it was found that tilianin increased PPARα and ACSL1 mRNA levels (p<0.05). Finally, tilianin docking studies with PPARα showed polar interactions with Glu269, Tyr314, His 440 and Tyr464 residues. In conclusion, short-term tilianin treatment might exert its antidiabetic and antihyperlipidemic effect by modulating a pro-inflammatory profile, and increasing adiponectin expression. In addition, our results suggest the possible interaction of tilianin with PPARα.

APOA5 and APOA1 polymorphisms are associated with triglyceride levels in Mexican children.

Dyslipidemia is an important risk factor for the development of several diseases. The genetic component of hypertriglyceridemia has been studied in adults, but little is known in children.

High Thyroid-stimulating Hormone Levels Increase Proinflammatory and Cardiovascular Markers in Patients with Extreme Obesity

BACKGROUND AND AIMS Obesity is an important health problem worldwide and many studies have suggested a relationship between obesity and thyroid function, with controversial results. Interestingly, high TSH levels have been involved with the presence of inflammatory state and risk for developing cardiovascular diseases in hypothyroid and obese patients. The aim in this work was to determine the prevalence of hypothyroidism in patients with extreme obesity and to determine whether their TSH levels were related to increased serum levels of inflammatory and cardiovascular markers. METHODS A cross-sectional study in 101 patients with extreme obesity (BMI ≥40) was performed. Anthropometric (weight, height and waist circumference) and biochemical (fasting glucose, glycosylated hemoglobin, triglycerides, total cholesterol, LDL-C, HDL-C and insulin) parameters were measured. TSH and FT4 levels as well as clinical exploration for diagnosis of hypothyroidism were carried out. Serum concentration of IL-10, IL-6, adiponectin, resistin, leptin, ICAM-1, VCAM-1 and E-selectin were determined. RESULTS A high prevalence for diabetes (37.6%), prediabetes (50.5%), dyslipidemia (74.3%), hypertension (61.4%) and hypothyroidism (48.5%) was observed in patients with extreme obesity. The presence of hypothyroidism increased serum concentration of proinflammatory cytokines IL-6 and leptin and decreased the antiinflammatory cytokine adiponectin. In addition, serum TSH levels showed a correlation for waist circumference, weight, BMI, A1c, insulin, IL-6, leptin, ICAM-1 and E-selectin. CONCLUSION There is a high prevalence for hypothyroidism in patients with extreme obesity. High levels of TSH contribute to elevate proinflammatory and cardiovascular risk markers, increasing the risk for development of cardiovascular diseases.

Vascular endothelial function is improved by oral glycine treatment in aged rats

Glycine has been used to reduce oxidative stress and proinflammatory mediators in some metabolic disorders; however, its effect on the vasculature has been poorly studied. The aim of this work was to explore the effect of glycine on endothelial dysfunction in aged rats. Aortic rings with intact or denuded endothelium were obtained from untreated or glycine-treated male Sprague-Dawley rats at 5 and 15 months of age. Concentration-response curves to phenylephrine (PHE) were obtained from aortic rings incubated with N(G)-nitro-l-arginine methyl ester (l-NAME), superoxide dismutase (SOD), indomethacin, SC-560, and NS-398. Aortic mRNA expression of endothelial nitric oxide synthase (eNOS), NADPH oxidase 4 (NOX-4), cyclooxygenase 1 (COX-1), cyclooxygenase 2 (COX-2), tumour necrosis factor (TNF)-α, and interleukin-1 β was measured by real time RT-PCR. The endothelial modulation of the contraction by PHE was decreased in aortic rings from aged rats. Glycine treatment improved this modulator effect and increased relaxation to acetylcholine. Glycine augmented the sensitivity for PHE in the presence of l-NAME and SOD. It also reduced the contraction by incubation with indomethacin, SC-560, and NS-398. Glycine increased the mRNA expression of eNOS and decreased the expression of COX-2 and TNF-α. Glycine improved the endothelium function in aged rats possibly by enhancing eNOS expression and reducing the role of superoxide anion and contractile prostanoids that increase the nitric oxide bioavailability.

Antidiabetic, antidyslipidemic and toxicity profile of ENV-2: A potent pyrazole derivative against diabetes and related diseases

Abstract Diabetes is a major health problem and a predisposition factor for further degenerative complications and, therefore, novel therapies are urgently needed. Currently, cannabinoid receptor 1 (CB1 receptor) antagonists have been considered as promissory entities for metabolic disorders treatment. Accordingly, the purpose of this work was the evaluation of the sub‐acute antidiabetic, anti‐hyperglycemic, antidyslipidemic and toxicological profile of ENV‐2, a potent hypoglycemic and antioxidant CB1 receptor antagonist. In this study, ENV‐2 showed a pronounced anti‐hyperglycemic effect even at a dose of 5 mg/kg (P<0.05) in a glucose tolerance test on normoglycemic rats. Moreover, after administration of ENV‐2 (16 mg/kg) to diabetic rats, a prominent antidiabetic activity was observed (P<0.05), which was higher than glibenclamide. Sub‐acute treatment (10 days) of ENV‐2 resulted in a significant reduction of plasma glucose (P<0.05). Also, the levels of peripheral lipids were improved; blood triacylglycerols (TG) and cholesterol (CHOL) were diminished (P<0.05). In addition, it was found that ENV‐2 reduced IL‐1&bgr; and IL‐18 mRNA expression in adipose tissue (P<0.05). Due to the satisfactory outcomes, we were interested in evaluating the toxicity of ENV‐2 in both acute and sub‐chronic approaches. Regarding the acute administration, the compound resulted to be non‐toxic and was grouped in category 5 according to OECD. It was also found that sub‐chronic administration did not increase the size of the studied organs, while no structural damage was observed in heart, lung, liver and kidney tissues. Finally, neither AST nor ALT damage hepatic markers were augmented. Graphical abstract Figure. No caption available.

Association between PPAR-γ2 Pro12Ala genotype and insulin resistance is modified by circulating lipids in Mexican children.

The Pro12Ala (rs1801282) polymorphism in peroxisome proliferator-activated receptor-γ2 (PPAR-γ2) has been convincingly associated with insulin resistance (IR) and type 2 diabetes (T2D) among Europeans, in interaction with a high-fat diet. Mexico is disproportionally affected by obesity and T2D however, whether the Pro12Ala polymorphism is associated with early metabolic complications in this population is unknown. We assessed the association of PPAR-γ2 Pro12Ala with metabolic traits in 1457 Mexican children using linear regression models. Interactions between PPAR-γ2 Pro12Ala and circulating lipids on metabolic traits were determined by adding an interaction term to regression models. We observed a high prevalence of overweight/obesity (49.2%), dyslipidemia (34.9%) and IR (11.1%). We detected nominally significant/significant interactions between lipids (total cholesterol, HDL-cholesterol, LDL-cholesterol), the PPAR-γ2 Pro12Ala genotype and waist-to-hip ratio, fasting insulin, HOMA-IR and IR (9.30 × 10−4  ≤ Pinteraction ≤ 0.04). Post-hoc subgroup analyses evidenced that the association between the PPAR-γ2 Pro12Ala genotype and fasting insulin, HOMA-IR and IR was restricted to children with total cholesterol or LDL-cholesterol values higher than the median (0.02 ≤ P ≤ 0.03). Our data support an association of the Pro12Ala polymorphism with IR in Mexican children and suggest that this relationship is modified by dyslipidemia.

Evaluating the transferability of 15 European-derived fasting plasma glucose SNPs in Mexican children and adolescents

Genome wide association studies (GWAS) have identified single-nucleotide polymorphisms (SNPs) that are associated with fasting plasma glucose (FPG) in adult European populations. The contribution of these SNPs to FPG in non-Europeans and children is unclear. We studied the association of 15 GWAS SNPs and a genotype score (GS) with FPG and 7 metabolic traits in 1,421 Mexican children and adolescents from Mexico City. Genotyping of the 15 SNPs was performed using TaqMan Open Array. We used multivariate linear regression models adjusted for age, sex, body mass index standard deviation score, and recruitment center. We identified significant associations between 3 SNPs (G6PC2 (rs560887), GCKR (rs1260326), MTNR1B (rs10830963)), the GS and FPG level. The FPG risk alleles of 11 out of the 15 SNPs (73.3%) displayed significant or non-significant beta values for FPG directionally consistent with those reported in adult European GWAS. The risk allele frequencies for 11 of 15 (73.3%) SNPs differed significantly in Mexican children and adolescents compared to European adults from the 1000G Project, but no significant enrichment in FPG risk alleles was observed in the Mexican population. Our data support a partial transferability of European GWAS FPG association signals in children and adolescents from the admixed Mexican population.

IRS1, TCF7L2, ADRB1, PPARG, and HHEX Polymorphisms Associated with Atherogenic Risk in Mexican Population

Objective. We aimed to explore the association between polymorphisms of IRS1 (rs1801278), TCF7L2 (rs7903146 and rs12255372), ADRB1 (rs1801253), PPARG (rs1801282), and HHEX (rs5015480) genes with atherogenic risk (AI = Total cholesterol/HDL) in MetS, T2D, and healthy populations from the Mexican Social Security Institute. Methodology and Results. Four hundred thirty-five MetS, 517 T2D, and 547 healthy individuals were selected. The association between the SNPs and the atherogenic index was evaluated by multiple linear regression and multinomial logistic regression models. The ADRB1 gene showed a statistically significant association with high-risk atherogenic index, OR = 2.94 (IC 95% 1.64–5.24; P < 0.0001) for the Arg/Gly variant, under the dominant model an OR = 2.96 (IC 95% 1.67–5.25; P < 0.0001), and under the Log additive model an OR = 2.52 (IC 95% 1.54–4.15; P < 0.0001). Conclusions. The Arg389Gly polymorphism of the ADRB1 gene may be a worthy biological marker to predict the risk of developing cardiovascular diseases given a high-risk atherogenic index.