Haydeé Rosas-Vargas

Methylenetetrahydrofolate Reductase C677T and Glutathione S-Transferase P1 A313G Are Associated with a Reduced Risk of Preeclampsia in Maya-Mestizo Women

Preeclampsia, a common complication of pregnancy, is characterized by elevated blood pressure and proteinuria developing after 20 weeks’ gestational age. Susceptibility to this syndrome is believed to have a genetic component. The aim of this study was to investigate whether or not the 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T and glutathione S−transferase P1 (GSTP1) A313G polymorphisms are associated with preeclampsia in Maya-Mestizo women. A case-control study was performed, in which 125 preeclamptic patients and 274 healthy controls were genotyped for the MTHFR C677T and GSTP1 A313G polymorphisms by real-time PCR allelic discrimination. Allele and genotype frequencies were compared using the χ2 tests. The MTHFR 677T allele and the 677TT genotype were significantly more frequent in the controls, suggesting an association with a decreased risk of preeclampsia (p=0.017 and p=0.007, respectively). Similarly, GSTP1 313GG/GC genotypes and the G allele were more frequent in controls, showing a significant association with reduced risk of preeclampsia (p=0.008 and p=0.013, respectively). Our results suggest, for the first time, that the MTHFR 677T and GSTP1 313G polymorphisms confer a significantly decreased risk of developing preeclampsia in the Mexican Maya-Mestizo population.

Dystrophins in developing retina: Dp260 expression correlates with synaptic maturation.

Dystrophin, the protein altered in Duchenne muscular dystrophy (DMD), is necessary for normal retinal function and exists in several isoforms. We examined the expression of dystrophin and utrophin proteins and transcripts in the rat retina at different developmental stages using Western blots and semi-quantitative RTPCR. Our results revealed the presence of utrophin (DRP1), G-utrophin and/or DRP2 and four dystrophin isoforms (Dp427, Dp260, Dp140, Dp71) in the normal adult rat retina. Only Dp260 showed a marked progressive increase with age at both protein and mRNA levels. This variation is consistent with the establishment of synaptic functions in the developing retina and suggests a key role for this apo-dystrophin in synaptogenesis.

IMMUNODETECTION ANALYSIS OF MUSCULAR DYSTROPHIES IN MEXICO

Introduction: The muscular dystrophies (MDs) result from perturbations in the myofibers. These alterations are induced in part by mechanical stress due to membrane cell fragility, disturbances in mechanotransduction pathways, muscle cell physiology, and metabolism. Methods: We analyzed 290 biopsies of patients with a clinical diagnosis of muscular dystrophy. Using immunofluorescence staining, we searched for primary and secondary deficiencies of 12 different proteins, including membrane, costamere, cytoskeletal, and nuclear proteins. In addition, we analyzed calpain‐3 by immunoblot. Results: We identified 212 patients with varying degrees of protein deficiencies, including dystrophin, sarcoglycans, dysferlin, caveolin‐3, calpain‐3, emerin, and merosin. Moreover, 78 biopsies showed normal expression of all investigated muscle proteins. The frequency rates of protein deficiencies were as follows: 52.36% dystrophinopathies; 18.40% dysferlinopathies; 14.15% sarcoglycanopathies; 11.32% calpainopathies; 1.89% merosinopathies; 1.42% caveolinopathies; and 0.47% emerinopathies. Deficiencies in lamin A/C and telethonin were not detected. Conclusion: We have described the frequency of common muscular dystrophies in Mexico. Muscle Nerve, 2012

Analysis of Polymorphisms in Genes (AGT, MTHFR, GPIIIa, and GSTP1) Associated with Hypertension, Thrombophilia and Oxidative Stress in Mestizo and Amerindian Populations of México

Several polymorphisms related to hypertension, thrombophilia, and oxidative stress has been associated with the development of cardiovascular disease. We analyzed the frequency of M235T angiotensinogen (AGT), A222V 5,10 methylenete-trahydrofolate reductase (MTHFR), L33P glycoprotein IIIa (GPIIIa), and I105V glutathione S-transferase P1 (GSTP1) polymorphisms in 285 individuals belonging to Mexican-Mestizo and five Amerindian population from México, by real time PCR allelic discrimination. Allele and genotype frequencies were compared using χ2 tests. All populations followed the Hardy Weinberg equilibrium for assay markers with the exception of the Triki, whose were in Hardy Weinberg dysequilibrium for the glutathione S-transferase P1 polymorphism. Interestingly, according to all the analyzed single nucleotide polymorphisms (SNPs), the Triki population was the most differentiated and homogeneous group of the six populations analyzed. A comparison of our data with those previously published for some Caucasian, Asian and Black populations showed quite significant differences. These differences were remarkable with all the Mexican populations having a lower frequency of the 105V allele of the glutathione S-transferase P1 and reduced occurrence of the 222A allele of the 5,10 methylenetetrahydrofolate reductase. Our results show the genetic diversity among different Mexican populations and with other racial groups.

Endothelial nitric oxide synthase gene polymorphism in the Indian and Mestizo populations of Mexico

Endothelium-derived nitric oxide (NO) is an important factor in vasodilation synthesized by endothelial nitric oxide synthase (eNOS). A polymorphism (894 G to T) in exon 7 of the eNOS gene causes the conversion of Glu to Asp in position 298. The Glu298Asp polymorphism has been extensively associated with cardiovascular disease. We determined the Glu298Asp polymorphism frequency in healthy Mexican Mestizo, Huastec, Mayo, and Mayan populations by the endonuclease restriction method. The four populations analyzed were in Hardy-Weinberg equilibrium. Allele frequencies were similar among Mexican populations but different when compared with Caucasians. However, when compared with allele frequencies in Asian populations, Mestizo and Huastec allele frequencies were significantly different. Genotypically, only the Mestizos presented Asp298 homozygosity. The absence of double mutants in Indian populations resembles that in Asians. With these data, we conclude that the low frequency of the eNOS Glu298Asp polymorphism in Indian and Mestizo populations of Mexico is related to the Asian origin of Amerindian groups.

Expression analysis of the SG-SSPN complex in smooth muscle and endothelial cells of human umbilical cord vessels.

Recently, participation of the sarcoglycan (SG)-sarcospan (SSPN) complex in the development of cardiomyopathy in patients with limb-girdle muscular dystrophy has been shown, and presence of the complex in smooth muscle may be important for the contraction/dilation process of vessels. However, there are few studies determining the SG-SSPN complex in vascular smooth muscle and endothelial cells of vessels. In this study, we analyzed by reverse transcriptase-polymerase chain reaction and immunofluorescence the expression of different components of the complex in vein/artery smooth muscle and endothelial cells of the human umbilical cord. By RNA analysis, we observed expression of α-, β-, γ-, δ-, Ε-SG, and SSPN in smooth muscle cells. In endothelial cells, RNA expression was restricted to β-, δ-, Ε-SG, and SSPN. At protein level, we observed in smooth muscle the presence of β-, δ-, Ε-SG, and SSPN. In endothelial cells, immunostaining only evidenced the presence of Ε-SG and SSPN. However, colocalization of SGs and SSPN with dystrophin and utrophin was noted. These results, interestingly, suggest that the SG-SSPN complex may either form with dystrophin or utrophin in smooth muscle cells, and with utrophin in endothelial cells. Additionally, we also observed in some smooth muscle regions the colocalization of the SG-SSPN complex with caveolin, with colocalization being more pronounced between Ε-SG-SSPN and caveolin in endothelial cells.

Expression and function of utrophin associated protein complex in stretched endothelial cells: dissociation and activation of eNOS.

Several studies have emphasized the relevance of dystrophin-associated protein complex (DAPC) to maintain the vascular function. Previously we postulated the presence of an utrophin associated protein complex (UAPC) in endothelium from umbilical cord vessels. In the present work, we demonstrate that utrophin (UTR) indeed forms a complex, with beta-dystroglycan (DG), epsilon-sarcoglycan (SG), caveolin-1 (cav-1), and endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVEC) by co-immunoprecipitation analysis. Additionally, we observed an increment in the protein levels of epsilon-SG, beta-DG, UTR and cav-1 after mechanical stretching. Interestingly, this stimulus also induced eNOS up-regulation, activation and release from the UAPC, and led to a significant increase in nitric oxide (NO) production. Finally, we propose that UAPC in HUVECs may play an important role in the regulation of vascular tone.

Expression and localization of utrophin in differentiating PC12 cells

To ascertain the role of utrophin in cultured neuronal cells, we investigated its expression and distribution along the NGF-induced differentiation of PC12 cells grown on different substrata. Utrophin mRNA was measured by RT-PCR assay and utrophin protein was quantified by immunoblot analysis. The distribution of utrophin and β-dystroglycan was analyzed by confocal microscopy. We demonstrate that utrophin protein was increased 4-fold during differentiation of cells grown on laminin. Concomitant with this up-regulation, utrophin was enriched at the growth cones in differentiating cells, where it co-localizes with β-dystroglycan. These data suggest the presence of a utrophin–β-dystroglycan complex in PC12 cells that participates in the formation and/or stabilization of the growth cone-extracellular matrix adhesion.

Children’s perception on obesity and quality of life: a Mexican survey

BackgroundChild obesity has become a major health problem worldwide. In order to design successful intervention strategies, it is necessary to understand how children perceive obesity and its consequences.MethodsWith the aim to evaluate scholar children perception of obesity as a significant factor on the quality of life, we developed and validated the “Obesity impact on the quality of life perception-questionnaire” (ObI-Q). We surveyed 1335 healthy children aged 6–12 years, randomly selected from elementary schools in Mexico City. The ObI-Q comprises eight multiple-choice items that explore aspects related to the quality of life during adult life; such as health, life span, emotional status, lifestyle, social recognition and economic status. In order to identify perceptional modifier factors, results were analyzed through multivariable logistic regression. Variables included gender, age, and child nutritional status, as well as the child’s perception of parental nutritional status.ResultsObI-Q results showed that most children (64.71%) considered obesity as a negative condition that influences health and social performance. This perception was inversely related to age (OR = 0.64, p = 0.003), as well as to the perception of their mother nutritional status (OR = 0.47, p = 0.01).ConclusionsThis study provides an overview of children’s perception on obesity and its consequences. Because the high proportion of schoolchildren who do not view obesity as an adverse consequence to the quality of life, then the results of this study could be used as part of strategies for the prevention of overweight and obesity.

Galectin-1 reduced the effect of LPS on the IL-6 production in decidual cells by inhibiting LPS on the stimulation of IκBζ

Pregnancy is a complex process where several physiological pathways interact. The down-regulated inflammatory response and the abundance of anti-inflammatory molecules during gestation may explain the acceptance of the fetus and the lack of immune response against it, even though it is a foreign tissue for the mother. NF-κB is a key regulator of the transcription of inflammatory genes, such as IL-8, IL-1β, TNF-α, or IL-6. Increased NF-κB activity that leads to the production of proinflammatory cytokines may induce obstetric disorders, such as preterm birth or abortion. Low activity of this transcription factor is associated with the beneficial anti-inflammatory environment during fetus development until delivery. Galectin-1 (Gal-1) is a lectin-type glycan-binding protein that is able to down-regulate inflammation. It has been shown that Gal-1 is abundantly expressed at the feto-maternal interface in humans, where it promotes maternal immune tolerance to the fetal semi-allograft. Gal-1 tolerance-promoting mechanisms have been established for adaptive immune cells, such as T cells and dendritic cells. However, the role of this lectin has not been established in non-immune cells at the feto-maternal interface. Here, we determined that Gal-1 is able to block the stimulating effect of LPS on IL-6 in human decidua cells. Our results show that Gal-1 acts by inhibiting the stimulation of the LPS-induced IκBζ expression, an NF-κB regulator involved in IL-6 gene transcription.