Montiel-Tellez et al., Endocrinol Metab Syndr 2016, 5:2
Endocrinol Metab Syndr
Objective: To determine the association between the c.+62G>A and g.-420C>G polymorphisms and Type 2
Diabetes (T2D) or obesity susceptibility for Mexicans. Additionally, we examined their overall effect across different
populations by a systematic review.
Methods: 164 Mexicans were classified as Healthy, Obese, or T2D. Genotypes were determined and associated
risk for the heterozygous, homozygous, dominant, recessive, and allelic genetic models were determined by calculating
the Odds Ratios (OR). For the meta-analysis, original publications that had determined RETN polymorphisms in T2D
or obese subjects were searched for in PubMed, Scopus, EBSCO, Ovid, and Wiley databases until November 2015,
using the search terms: T2D, obesity, RETN, and polymorphism. Pooled ORs were computed using a random-effects
or fixed-effects models.
Results: For our cohort, no associations were observed between the polymorphisms and obesity or T2D. The metaanalysis
indicates an increased risk of obesity among carriers of the g.-420G allele for the heterozygous and dominant
models (OR=1.33 and OR=1.30, p<0.05, respectively). By regional assessment, Africans were associated with an
elevated risk of developing T2D (OR=2.35-7.17, p<0.05) and obesity (OR=1.54-2.13, p<0.05). North Americans had
an increased risk of developing obesity for the heterozygous and dominant models (OR=1.49and OR=1.42, p<0.05,
respectively). No associations were determined between the c.+62 polymorphism and obesity or T2D.
Conclusion: For Mexicans, none of the polymorphisms were associated with a risk of developing obesity or T2D.
However, there is an increased risk of developing obesity for the whole population for subjects who carry the g.-420G
Background: Insulin Sensitivity (IS) and Insulin Resistance (IR) mark the development of Type 2 Diabetes.
Many reports have demonstrated that anthropometric indices can detect IS and IR, however ethnic variations can
influence the optimal cutoff value. Therefore, the aim of this study was to determine the optimal cutoff value for
Waist Circumference (WC), Body-Mass Index (BMI), Waist-To-Hip Ratio (WHR), Waist-To-Height Ratio (WHtR), and
percent Body Fat (BF %) to determine IS and IR from subjects from central Mexico.
Methods: WC, BMI, WHR, WHtR, BF%, fasting plasma glucose, and insulin were determined in 569 subjects
(male=286 & females=283; ages: 18-84). IR and IS were determined by the Homeostatic Model Assessment online
calculator and Quantitative Insulin Sensitivity Check Index, respectively. The area under the Receiver Operating
Characteristic curve (AUC) and Youden´s index for each anthropometric index was calculated to determine its cutoff
value. Cutoff value´s efficiency was measured by determining the test´s accuracy.
Results: WC, BMI, WHtR and BF% negatively correlated IS and positively correlated to IR (p<0.0001). WHR
did not correlate with IS nor IR. AUC analysis showed that WC, BMI, WHtR and BF% were acceptable test to
determine IS and IR (IS: males: AUC=0.736-0.770 and females: AUC=0.648-0.666; IR: males: AUC=0.740-0.760
and females: AUC=0.681-0.709, p<0.001). Comparison of AUC demonstrated that WC, BMI, WHtR and BF% had
similar efficiency to determine IS and IR. However, after determining the optimal cutoff value and using highest
test accuracy, we determined the better indicators for IS was WHtR (cutoff=0.540, accuracy=76.8%) and BF%
(cutoff=31.5%, accuracy=68.0%) and for IR was WC (cutoff=99.5 cm, accuracy=71.0%) and BMI (cutoff=31.6 kg/m2,
accuracy=79.9%) for males and females, respectively.
Conclusion: When comparing multiple anthropometric indices, we determined that WHtR and WC for males
and BF% and BMI for females were better indicators for determining IS and IR, respectively.
Diabetes hoy para el médico y el profesional de la salud, 2011; XIII (5): 2814-2822.
Diabetes hoy para el médico y el profesional de la salud
The metabolic syndrome is considered a growing public health problem worldwide. Recent studies have suggested that this disease may result from different pathophysiological mechanisms that may be involved simultaneosly. Outstanding among them, the oxidative stress (OS), this occurs when the balance between antioxidant mechanisms and the production of pro-oxidant molecules is altered. The OS stimulates the production of cytokines (interleukin (IL) 6, TNF a, IL-8, IL-18, etc) that initiate an inflammatory response and thus alteration in the metabolism og carbohydrates, lipids and proteins. The increase in the secretion of pro-oxidant molecules, it suggested is responsible for the generation of insuline resistance in skeletal muscle, adipose tissue and impaired insulin secretionby pancreatic cells. Besides the above, the accumulation of pro-oxidant molecules in the body cause damage and activationof specific pathways, both events lead to proliferation, dysfunction, adaptation or cell death.