RESUMEN

Neural tube defects (NTDs) are the most common congenital anomalies of the CNS. It is widely appreciated that both genetic and environmental factors contribute to their etiology. The inability to ascribe clear genetic patterns of inheritance to various NTD phenotypes suggests it is possible that epigenetic mechanisms are involved in the etiology of NTDs. In this context, the contribution of DNA methylation as an underlying contributing factor to the etiology of NTDs has been extensively reviewed. Here, an updated accounting of the evidence linking post-translational histone modifications to these birth defects, relying heavily upon studies in humans, and the possible molecular implications inferred from reports based on cellular and animal models, are presented.

Asunto(s)

Histonas , Defectos del Tubo Neural , Animales , Humanos , Histonas/metabolismo , Código de Histonas , Defectos del Tubo Neural/genética , Epigénesis Genética , Metilación de ADN

RESUMEN

OBJECTIVES: The 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR) is the enzyme controlling the rate-limiting step in the synthesis of cholesterol, sterols, and isoprenoids in the mevalonate biosynthetic pathway. Impaired function of HMGCR in zebrafish produces craniofacial malformations and orofacial cleft, mainly affecting the post-migratory neural crest cells with little earlier effect. Here we investigate morphogenetic and cellular mechanisms underlying the generation of these malformations. METHODS: The morphology of chondrocytes in the lower jaw and the proliferation/apoptosis in the ethmoid plate were analysed in hmgcr1b mutants and in embryos treated with atorvastatin. In the ceratohyal of treated embryos, we measured the number and dimensions of chondrocytes. In the ethmoid plate, we performed proliferation and apoptosis assays to quantify the number of cells undergoing each process in both hmgcr1b mutants and pharmacologically treated embryos. All embryos were imaged using confocal microscopy and processed to obtain maximum intensity z-projection. RESULTS: The shortening of the ceratohyal is produced by a moderate reduction in the number of cells combined with isometric shrinkage of the chondrocytes. At the same time, the shortening of the ethmoid plate is due to a combination of a slightly diminished proliferation with massive abnormal apoptosis at the proliferation front. CONCLUSION: HMGCR function is necessary for the normal survival and morphology of chondrocytes during condensation and chondrogenesis in the developing palate and jaw. Further studies are required to establish the pathways through which HMGCR acts on apoptosis, proliferation, and cell size during normal craniofacial development.

Asunto(s)

Labio Leporino , Fisura del Paladar , Animales , Pez Cebra , Condrocitos , Morfogénesis

RESUMEN

Aim: To assess the association between PEMT variants and nonsyndromic cleft lip with or without cleft palate in Chile and the effects of these variants on global DNA methylation. Subjects & methods: The authors obtained genotypes for nine variants from 247 cases and 453 controls for genotype-phenotype associations. The effect of significant polymorphisms on global DNA methylation (percentage of long interspersed element-1 methylation) was evaluated in a subsample of 95 controls. Results: After multiple comparison corrections, variants rs7649 and rs4646409 were associated with nonsyndromic cleft lip with or without cleft palate. Carriers of risk alleles presented lower DNA methylation levels than noncarriers. Conclusion: According to functional analysis for risk variants from previous reports, the authors infer that a decrease of methyl group availability is occurring in affected subjects.

---

This study evaluated if variants in the gene named PEMT confers an increased risk for nonsyndromic cleft lip with or without cleft palate in Chile and its possible effects on methylation of DNA, a variable linked to gene expression modulation. The study found that the variants recognized as rs7649 and rs4646409 increase the risk of nonsyndromic cleft lip with or without cleft palate in the Chilean population and decrease DNA methylation. The authors conclude that this gene may be involved in this birth defect. New studies are needed to confirm the relation between this condition and DNA methylation mediated by these genetic variants.

Asunto(s)

Labio Leporino , Fisura del Paladar , Chile , Labio Leporino/genética , Fisura del Paladar/genética , Genotipo , Humanos , Fosfatidiletanolamina N-Metiltransferasa/genética , Polimorfismo de Nucleótido Simple

RESUMEN

The aims of this study were to assess the association between polymorphisms within genes involved in vitamin B12 transport and nonsyndromic cleft lip with or without cleft palate (NSCL/P) and global DNA methylation in Chile. From 247 cases and 453 controls, we obtained variant genotypes for CBLIF, CUBN, AMN, ABCC1, CD320, and TCN2 from a single nucleotide polymorphisms array. Global DNA methylation in 95 controls was obtained through LINE-1 methylation. After multiple comparison corrections, only rs780807 in CUBN remains associated with NSCL/P at dominant model (OR 0.564, p-value = 0.0006, q-value = 0.0450). Carriers of protective allele showed lower levels of DNA methylation than non-carriers (p = 0.0259). Further studies are necessary in order to explain relations with the phenotype and DNA methylation due to the absence of functional evidence for rs780807 in CUBN.

Asunto(s)

Labio Leporino , Fisura del Paladar , Estudios de Casos y Controles , Chile , Labio Leporino/genética , Fisura del Paladar/genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Polimorfismo de Nucleótido Simple , Vitamina B 12

RESUMEN

Non-syndromic orofacial clefts (NSOFCs) are prevalent birth defects with a complex etiology where several interacting genetic and environmental factors have been observed. This narrative review describes maternal exposures that have been significantly associated with protective effects or risk factors. The statistically significant information reported here was found in meta-analysis studies, taking advantage of their precision in defining intervention effects and their management of heterogeneity between studies. In addition, I propose a hypothesis explaining the biological basis for the results of the meta-analyses. This review aims to improve the evidence available in parent counseling, to prevent the occurrence of orofacial clefts by suggesting lifestyle changes.

Asunto(s)

Labio Leporino , Fisura del Paladar , Labio Leporino/etiología , Labio Leporino/genética , Fisura del Paladar/epidemiología , Fisura del Paladar/genética , Femenino , Humanos , Factores de Riesgo

RESUMEN

The aim of this study was to evaluate, in a case-control design, the association between maternal genotypes for variants in 23 genes involved in folate/one-carbon metabolism and nonsyndromic cleft lip with or without cleft palate (NSCL/P) in a Chilean population. After applying several filters to an Illumina array, we extracted 175 single nucleotide polymorphisms (SNPs) from 150 mothers of NSCL/P cases and 150 control women. Association was evaluated using computed odds ratio (OR) with a 95% confidence interval (95% CI) in additive, recessive, and dominant models. After multiple comparison correction, only SNP rs4451422 (A>C), located 237 bp downstream of the gene encoding the human folylpolyglutamate synthetase (FPGS), maintained a significant association with NSCL/P in the offspring (OR 3.03; 95% CI 1.69-5.26). The variant rs4451422 is associated with a decrease in FPGS expression according to database annotation. Our results lead to a new hypothesis that a lower activity of FPGS enzyme reduces intracellular folate levels and increases the risk of an offspring having NSCL/P.

Asunto(s)

Labio Leporino , Fisura del Paladar , Carbono , Chile , Labio Leporino/genética , Fisura del Paladar/genética , Ácido Fólico , Genotipo , Humanos

RESUMEN

BACKGROUND: Helicobacter pylori is detected by pathogen recognition receptors including toll-like receptors (TLR) and nucleotide-binding oligomerization domain (NOD)-like receptors, eliciting an innate immune response against this bacteria. The aim of this study was to assess if polymorphisms of TLR2, TLR4, TLR5, NOD1 and NOD2 genes are associated with gastric cancer, in particular in individuals infected with H. pylori. RESULTS: A case-control study of 297 gastric cancer patients and 300 controls was performed to assess the association of 17 polymorphisms. Analyses performed under the allele model did not find association with gastric cancer. However, NOD1 rs2075820 (p.E266K) showed association with intestinal-type gastric cancer among H. pylori infected subjects (OR = 2.69, 95% CI 1.41-5.13, p = 0.0026). The association was not statistically significant in diffuse-type gastric cancer cases (OR = 1.26, 95% CI 0.63-2.52, p = 0.51). When the analyses were performed in patients carrying H. pylori strains harboring the cag pathogenicity island (cagPAI), we noticed significant association with NOD1 rs2075820 (OR = 4.90, 95% CI 1.80-3.36, p = 0.0019), in particular for intestinal-type gastric cancer cases (OR = 7.16, 95% CI 2.40-21.33, p = 4.1 × 10- 4) but not among diffuse-type gastric cancer cases (OR = 3.39, 95% CI 1.13-0.10, p = 0.03). CONCLUSIONS: NOD1 rs2075820 increases the risk of intestinal-type gastric cancer among individuals infected with H. pylori, particularly in those harboring the cagPAI.

Asunto(s)

Infecciones por Helicobacter , Proteína Adaptadora de Señalización NOD1/genética , Neoplasias Gástricas , Estudios de Casos y Controles , Islas Genómicas , Infecciones por Helicobacter/genética , Helicobacter pylori , Humanos , Neoplasias Gástricas/genética

Asunto(s)

COVID-19 , Altitud , Humanos , SARS-CoV-2

RESUMEN

BACKGROUND: The S-adenosyl-methionine (SAM) availability is crucial for DNA methylation, an epigenetic mechanism involved in nonsyndromic cleft lip with or without cleft palate (NSCL/P) expression. The aim of this study was to assess the association between single-nucleotide polymorphisms (SNPs) of genes involved in SAM synthesis and NSCL/P in a Chilean population. METHODS: In 234 cases and 309 controls, 18 SNPs in AHCY, MTR, MTRR, and MAT2A were genotyped, and the association between them and the phenotype was evaluated based on additive (allele), dominant, recessive and haplotype models, by odds ratio (OR) computing. RESULTS: Three deep intronic SNPs of MTR showed a protective effect on NSCL/P expression: rs10925239 (OR 0.68; p = 0.0032; q = 0.0192), rs10925254 (OR 0.66; p = 0.0018; q = 0.0162), and rs3768142 (OR 0.66; p = 0.0015; q = 0.0162). Annotations in expression database demonstrate that the protective allele of the three SNPs is associated with a reduction of MTR expression summed to the prediction by bioinformatic tools of its potentiality to modify splicing sites. CONCLUSIONS: The protective effect against NSCL/P of these intronic MTR SNPs seems to be related to a decrease in MTR enzyme expression, modulating the SAM availability for proper substrate methylation. However, functional analyses are necessary to confirm our findings. IMPACT: SAM synthesis pathway genetic variants are factors associated to NSCL/P. This article adds new evidence for folate related genes in NSCL/P in Chile. Its impact is to contribute with potential new markers for genetic counseling.

Asunto(s)

5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/genética , Adenosilhomocisteinasa/genética , Labio Leporino/genética , Fisura del Paladar/genética , Ferredoxina-NADP Reductasa/genética , Metionina Adenosiltransferasa/genética , Polimorfismo de Nucleótido Simple , S-Adenosilmetionina/metabolismo , Alelos , Chile/epidemiología , Labio Leporino/fisiopatología , Fisura del Paladar/fisiopatología , Femenino , Frecuencia de los Genes , Genes Dominantes , Genes Recesivos , Predisposición Genética a la Enfermedad , Genotipo , Haplotipos , Humanos , Masculino , Metionina/genética , Oportunidad Relativa

RESUMEN

BACKGROUND: Helicobacter pylori is detected by pathogen recognition receptors including toll-like receptors (TLR) and nucleotide-binding oligomerization domain (NOD)-like receptors, eliciting an innate immune response against this bacteria. The aim of this study was to assess if polymorphisms of TLR2, TLR4, TLR5, NOD1 and NOD2 genes are associated with gastric cancer, in particular in individuals infected with H. pylori. RESULTS: A case-control study of 297 gastric cancer patients and 300 controls was performed to assess the association of 17 polymorphisms. Analyses performed under the allele model did not find association with gastric cancer. However, NOD1 rs2075820 (p.E266K) showed association with intestinal-type gastric cancer among H. pylori infected subjects (OR = 2.69, 95% CI 1.41-5.13, p = 0.0026). The association was not statistically significant in diffuse-type gastric cancer cases (OR = 1.26, 95% CI 0.63-2.52, p = 0.51). When the analyses were performed in patients carrying H. pylori strains harboring the cag pathogenicity island (cagPAI), we noticed significant association with NOD1 rs2075820 (OR = 4.90, 95% CI 1.80-3.36, p = 0.0019), in particular for intestinal-type gastric cancer cases (OR = 7.16, 95% CI 2.40-21.33, p = 4.1 × 10- 4) but not among diffuse-type gastric cancer cases (OR = 3.39, 95% CI 1.13-0.10, p = 0.03). CONCLUSIONS: NOD1 rs2075820 increases the risk of intestinal-type gastric cancer among individuals infected with H. pylori, particularly in those harboring the cagPAI.

Asunto(s)

Humanos , Neoplasias Gástricas/genética , Infecciones por Helicobacter/genética , Proteína Adaptadora de Señalización NOD1/genética , Estudios de Casos y Controles , Helicobacter pylori , Islas Genómicas

RESUMEN

Aim: To evaluate the risk of nonsyndromic orofacial clefts (NSOFCs) associated with LINE-1 methylation, as a marker of global DNA methylation, and the effect of MTHFR functional variants on this variable. Patients & methods: LINE-1 methylation was evaluated by bisulfite modification coupled to DNA pyrosequencing in 95 NSOFC cases and 95 controls. In these subjects, MTHFR genotypes for variants c.C677T (rs1801133) and c.A1298C (rs1801131) were obtained. Results: Middle levels (second tertile) of LINE-1 methylation increase the risk of NSOFCs. In addition, LINE-1 methylation depends on c.A1298C genotypes in controls but not in cases. Conclusion: A nonlinear association between global DNA methylation and NSOFCs was detected in this Chilean population, which appears to be influenced by MTHFR functional variants.

Asunto(s)

Encéfalo/anomalías , Labio Leporino/genética , Fisura del Paladar/genética , Metilación de ADN , Elementos de Nucleótido Esparcido Largo , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Chile , Humanos , Lactante , Recién Nacido , Polimorfismo de Nucleótido Simple

RESUMEN

Genetic variants are considered risk factors for gastric cancer. To date, 61 polymorphisms have been identified as associated with this disease. The aim of the present study was to analyze the association of some of those polymorphisms with GC in Chile. We performed a case-control study including 310 gastric cancer cases and 311 controls to assess the association of 36 single-nucleotide polymorphisms genotyped by Global Screening Array (GSA). Three polymorphisms was significantly associated: PSCA rs2294008 (allele model, OR = 1.49, 95%CI 1.17-1.88, P = 1.08 × 10-3), IL-4 rs2243250 (allele model, OR = 1.28, 95%CI 1.01-1.62, P = 0.04), and MUC1 rs4072037 (allele model, OR = 0.78, 95%CI 0.61-0.99, P = 0.04).PSCA rs2294008, IL-4 rs2243250 and MUC1 rs4072037 are associated with gastric cancer in Chile. It suggests that those polymorphisms could be used as biomarkers to assess the genetic risk for this cancer outside of the previously studied populations, not only for East Asians and Caucasians populations.

Asunto(s)

Antígenos de Neoplasias/genética , Predisposición Genética a la Enfermedad/genética , Interleucina-4/genética , Mucina-1/genética , Proteínas de Neoplasias/genética , Polimorfismo de Nucleótido Simple , Neoplasias Gástricas/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Estudios de Casos y Controles , Chile , Femenino , Proteínas Ligadas a GPI/genética , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven

RESUMEN

The aim of this study was to assess the association between IRF6 single nucleotide polymorphisms and nonsyndromic cleft lip, with or without cleft palate (NSCL/P), in a Chilean population, based on a case-control sample and confirmed in a case-parent trio population. In a sample of 150 Chilean case-parent trios and 164 controls (cohort 1), we evaluated the association between three common IRF6 variants (rs764093, rs2236909, rs2235375) and NSCL/P using odds ratio (OR) for case-control and case-parent trios and in a combined OR of both designs. To confirm associations from the cohort 1, we increased the sample size to 215 triads and 320 controls (cohort 1 + cohort 2). The combined OR for the cohort 1 reveals that the rs2235375 C allele is associated with NSCL/P in Chile (OR 1.34; p = 0.013), which was supported by the results for the two cohorts (OR 1.29; p = 0.006). Bioinformatic prediction showed that this variant, located 27 bp downstream from IRF6 exon 6, potentially alters the splicing process and based on functional annotations is associated with a decrease of gene expression. We propose that the C allele of rs2235375 from IRF6 gene seems to be a risk factor for NSCL/P in a Chilean population. However, we cannot discard a population stratification bias in our findings. On the other hand, further studies are necessary to confirm the biological role of rs2235375 in IRF6 function at craniofacial development level.

Asunto(s)

Labio Leporino/genética , Fisura del Paladar/genética , Predisposición Genética a la Enfermedad , Factores Reguladores del Interferón/genética , Polimorfismo de Nucleótido Simple , Alelos , Estudios de Casos y Controles , Chile , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Genotipo , Humanos , Masculino

RESUMEN

BACKGROUND: Current South American populations trace their origins mainly to three continental ancestries, i.e. European, Amerindian and African. Individual variation in relative proportions of each of these ancestries may be confounded with socio-economic factors due to population stratification. Therefore, ancestry is a potential confounder variable that should be considered in epidemiologic studies and in public health plans. However, there are few studies that have assessed the ancestry of the current admixed Chilean population. This is partly due to the high cost of genome-scale technologies commonly used to estimate ancestry. In this study we have designed a small panel of SNPs to accurately assess ancestry in the largest sampling to date of the Chilean mestizo population (n = 3349) from eight cities. Our panel is also able to distinguish between the two main Amerindian components of Chileans: Aymara from the north and Mapuche from the south. RESULTS: A panel of 150 ancestry-informative markers (AIMs) of SNP type was selected to maximize ancestry informativeness and genome coverage. Of these, 147 were successfully genotyped by KASPar assays in 2843 samples, with an average missing rate of 0.012, and a 0.95 concordance with microarray data. The ancestries estimated with the panel of AIMs had relative high correlations (0.88 for European, 0.91 for Amerindian, 0.70 for Aymara, and 0.68 for Mapuche components) with those obtained with AXIOM LAT1 array. The country's average ancestry was 0.53 ± 0.14 European, 0.04 ± 0.04 African, and 0.42 ± 0.14 Amerindian, disaggregated into 0.18 ± 0.15 Aymara and 0.25 ± 0.13 Mapuche. However, Mapuche ancestry was highest in the south (40.03%) and Aymara in the north (35.61%) as expected from the historical location of these ethnic groups. We make our results available through an online app and demonstrate how it can be used to adjust for ancestry when testing association between incidence of a disease and nongenetic risk factors. CONCLUSIONS: We have conducted the most extensive sampling, across many different cities, of current Chilean population. Ancestry varied significantly by latitude and human development. The panel of AIMs is available to the community for estimating ancestry at low cost in Chileans and other populations with similar ancestry.

Asunto(s)

Etnicidad/genética , Genética de Población/organización & administración , Indígenas Sudamericanos/genética , Polimorfismo de Nucleótido Simple/genética , Grupos de Población/genética , Chile , Femenino , Frecuencia de los Genes/genética , Marcadores Genéticos/genética , Genotipo , Técnicas de Genotipaje , Humanos , Masculino , Filogeografía , Saliva

RESUMEN

OBJECTIVE: To assess the association between polymorphic variants from SHMT1 and MTHFS genes, involved in the cytoplasmic futile folate cycle, and the risk of nonsyndromic cleft lip with or without cleft palate (NSCL/P) in the Chilean population. SUBJECTS AND METHODS: In a sample of 139 Chilean NSCL/P cases and 278 controls, we obtained the genotypes for nine variants of SHMT1 and MTHFS and the association between them and the phenotype was evaluated using odds ratios (OR) in additive (allele), dominant, and recessive models. RESULTS: After correction for multiple comparisons, only the variant rs1979277 (G > A; p.Leu474Phe) from SHMT1 showed a significant and protective effect for additive (OR 0.60; 95% CI 0.42-0.86; p = .0054, q = 0.0488) and dominant models (OR 0.48; 95% CI 0.29-0.75; p = .0009; q = 0.0081). Our bioinformatic prediction plus functional evidence from previous reports demonstrate that the A allele for this missense variant decreases the enzymatic activity. CONCLUSIONS: Owing to the rs1979277 A allele, which reduces the cytoplasmic SHMT activity and has a higher frequency in controls than in NSCL/P cases, we hypothesized that a low enzyme activity may increase the cytoplasmic concentration of folates and, therefore, explain the protective role against OFCs.

Asunto(s)

Labio Leporino/genética , Fisura del Paladar/genética , Glicina Hidroximetiltransferasa/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Chile , Femenino , Genotipo , Humanos , Masculino

RESUMEN

BACKGROUND: Current South American populations trace their origins mainly to three continental ancestries, i.e. European, Amerindian and African. Individual variation in relative proportions of each of these ancestries may be confounded with socio-economic factors due to population stratification. Therefore, ancestry is a potential confounder variable that should be considered in epidemiologic studies and in public health plans. However, there are few studies that have assessed the ancestry of the current admixed Chilean population. This is partly due to the high cost of genome-scale technologies commonly used to estimate ancestry. In this study we have designed a small panel of SNPs to accurately assess ancestry in the largest sampling to date of the Chilean mestizo population (n = 3349) from eight cities. Our panel is also able to distinguish between the two main Amerindian components of Chileans: Aymara from the north and Mapuche from the south. RESULTS: A panel of 150 ancestry-informative markers (AIMs) of SNP type was selected to maximize ancestry informativeness and genome coverage. Of these, 147 were successfully genotyped by KASPar assays in 2843 samples, with an average missing rate of 0.012, and a 0.95 concordance with microarray data. The ancestries estimated with the panel of AIMs had relative high correlations (0.88 for European, 0.91 for Amerindian, 0.70 for Aymara, and 0.68 for Mapuche components) with those obtained with AXIOM LAT1 array. The country's average ancestry was 0.53 ± 0.14 European, 0.04 ± 0.04 African, and 0.42 ± 0.14 Amerindian, disaggregated into 0.18 ± 0.15 Aymara and 0.25 ± 0.13 Mapuche. However, Mapuche ancestry was highest in the south (40.03%) and Aymara in the north (35.61%) as expected from the historical location of these ethnic groups. We make our results available through an online app and demonstrate how it can be used to adjust for ancestry when testing association between incidence of a disease and nongenetic risk factors. CONCLUSIONS: We have conducted the most extensive sampling, across many different cities, of current Chilean population. Ancestry varied significantly by latitude and human development. The panel of AIMs is available to the community for estimating ancestry at low cost in Chileans and other populations with similar ancestry.

Asunto(s)

Humanos , Masculino , Femenino , Etnicidad/genética , Indígenas Sudamericanos/genética , Polimorfismo de Nucleótido Simple/genética , Grupos de Población/genética , Genética de Población/organización & administración , Saliva , Marcadores Genéticos/genética , Chile , Filogeografía , Técnicas de Genotipaje , Frecuencia de los Genes/genética , Genotipo

RESUMEN

Cardiovascular risk associated with fetal growth restriction (FGR) could result from an early impaired vascular function. However, whether this effect results in premature vascular aging has not been addressed. We studied the ex vivo reactivity of carotid and femoral arteries in fetal (near term), adults (eight months-old) and aged (16 months-old) guinea pigs in normal (control) and FGR offspring. Additionally, an epigenetic marker of vascular aging (i.e., LINE-1 DNA methylation) was evaluated in human umbilical artery endothelial cells (HUAEC) from control and FGR subjects. Control guinea pig arteries showed an increased contractile response (KCl-induced) and a progressive impairment of NO-mediated relaxing responses as animals get older. FGR was associated with an initial preserved carotid artery reactivity as well as a later significant impairment in NO-mediated responses. Femoral arteries from FGR fetuses showed an increased contractility but a decreased relaxing response compared with control fetuses, and both responses were impaired in FGR-adults. Finally, FGR-HUAEC showed decreased LINE-1 DNA methylation compared with control-HUAEC. These data suggest that the aging of vascular function occurs by changes in NO-mediated responses, with limited alterations in contractile capacity. Further, these effects are accelerated and imposed at early stages of development in subjects exposed to a suboptimal intrauterine environment.

Asunto(s)

Envejecimiento/patología , Endotelio Vascular/crecimiento & desarrollo , Retardo del Crecimiento Fetal/patología , Animales , Arterias Carótidas/crecimiento & desarrollo , Arterias Carótidas/patología , Arterias Carótidas/fisiopatología , Células Cultivadas , Metilación de ADN , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Femenino , Arteria Femoral/crecimiento & desarrollo , Arteria Femoral/patología , Arteria Femoral/fisiopatología , Retardo del Crecimiento Fetal/genética , Cobayas , Humanos , Elementos de Nucleótido Esparcido Largo/genética , Óxido Nítrico/metabolismo , Vasoconstricción , Vasodilatación

RESUMEN

Most peripheral serotonin (5-hydroxytryptamine (5HT)) is synthetized in the gut with platelets being its main circulating reservoir. 5HT is acting as a hormone in key organs to regulate glucose and lipid metabolism. However, the relation between platelet 5HT levels and traits related to glucose homeostasis and lipid metabolism in humans remains poorly explored. The objectives of this study were (a) to assess the association between platelet 5HT levels and plasma concentration of nonesterified fatty acids (NEFAs) and some adipokines including leptin and its soluble leptin receptor (sOb-R), (b) to assess the association between platelet 5HT levels and anthropometric traits and indexes of insulin secretion/sensitivity derived from oral glucose tolerance test (OGTT), and (c) to evaluate changes in platelet 5HT levels in response to OGTT. In a cross-sectional study, 59 normoglycemic women underwent a standard 2-hour OGTT. Plasma leptin, sOb-R, total and high molecular weight adiponectin, TNFα, and MCP1 were determined by immunoassays. Platelet 5HT levels and NEFAs were measured before and after OGTT. The free leptin index was calculated from leptin and sOb-R measurements. Insulin sensitivity indexes derived from OGTT (HOMA-S and Matsuda ISICOMP) and plasma NEFAs (Adipose-IR, Revised QUICKI) were also calculated. Our data show that among metabolic traits, platelet 5HT levels were associated with plasma sOb-R (r = 0.39, p = 0.003, corrected p = 0.018). Platelet 5HT levels were reduced in response to OGTT (779 ± 237 vs.731 ± 217 ng/109 platelets, p = 0.005). In conclusion, platelet 5HT levels are positively associated with plasma sOb-R concentrations and reduced in response to glucose intake possibly indicating a role of peripheral 5HT in leptin-mediated appetite regulation.

Asunto(s)

Adipoquinas/sangre , Plaquetas/química , Receptores de Leptina/sangre , Serotonina/sangre , Adiponectina/sangre , Adulto , Antropometría , Glucemia/análisis , Índice de Masa Corporal , Quimiocina CCL2/sangre , Chile , Estudios Transversales , Ácidos Grasos no Esterificados/metabolismo , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/sangre , Resistencia a la Insulina , Leptina/sangre , Metabolismo de los Lípidos , Lípidos/sangre , Receptores de Leptina/genética , Factor de Necrosis Tumoral alfa/sangre , Adulto Joven

RESUMEN

OBJECTIVE: Nonsyndromic cleft lip with or without cleft palate (NSCL/P) is a birth defect for which several genes susceptibility genes been proposed. Consequently, it has been suggested that many of these genes belong to common inter-related pathways during craniofacial development gene-gene interaction. We evaluated the presence of gene-gene interaction for single nucleotide polymorphisms within interferon regulatory factor 6 (IRF6), muscle segment homeobox 1 (MSX1), bone morphogenetic protein 4 (BMP4) and transforming growth factor 3 (TGFB3) genes in NSCL/P risk in Chilean case-parent trios. DESIGN: From previous studies, we retrieved genotypes for 13 polymorphic variants within these four genes in 152 case-parent trios. Using the trio package (R) we evaluate the gene-gen interaction in genetic markers pairs applying a 1°-of-freedom test (1df) and a confirmatory 4°-of-freedom (4df) test for epistasis followed by both a permutation test and a Benjamini-Hochberg test for multiple comparisons adjustment. RESULTS: We found evidence of gene-gene interaction for rs6446693 (MSX1) and rs2268625 (TGFB3) (4df p = 0.024; permutation p = 0.015, Benjamini-Hochberg p = 0.001). CONCLUSIONS: A significant gene-gene interaction was detected for rs6446693 (MSX1) and rs2268625 (TGFB3). This finding is concordant with research in animal models showing that MSX1 and TGFB3 are expressed in common molecular pathways acting in an epistatic manner during maxillofacial development.

Asunto(s)

Labio Leporino/genética , Fisura del Paladar/genética , Epistasis Genética/genética , Etnicidad/genética , Proteína Morfogenética Ósea 4/genética , Chile , Anomalías Congénitas/genética , Femenino , Marcadores Genéticos , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Factores Reguladores del Interferón/genética , Factor de Transcripción MSX1/genética , Masculino , Anomalías Maxilofaciales/genética , Padres , Polimorfismo de Nucleótido Simple/genética , Factor de Crecimiento Transformador beta3/genética

RESUMEN

The RAS/RAF/MEK/ERK pathway regulates certain cellular functions, including cell proliferation, differentiation, survival, and apoptosis. Dysregulation of this pathway leads to the occurrence and progression of cancers mainly by somatic mutations. This study aimed to assess if polymorphisms of the RAS/RAF/MEK/ERK pathway are associated with gastric cancer. A case-control study of 242 gastric cancer patients and 242 controls was performed to assess the association of 27 single nucleotide polymorphisms (SNPs) in the RAS/RAF/MEK/ERK pathway genes with gastric cancer. Analyses performed under the additive model (allele) showed four significantly associated SNPs: RAF1 rs3729931 (Odds ratio (OR) = 1.54, 95%, confidence interval (CI): 1.20⁻1.98, p-value = 7.95 × 10-4), HRAS rs45604736 (OR = 1.60, 95% CI: 1.16⁻2.22, p-value = 4.68 × 10-3), MAPK1 rs2283792 (OR = 1.45, 95% CI: 1.12⁻1.87, p-value = 4.91 × 10-3), and MAPK1 rs9610417 (OR = 0.60, 95% CI: 0.42⁻0.87, p-value = 6.64 × 10-3). Functional annotation suggested that those variants or their proxy variants may have a functional effect. In conclusion, this study suggests that RAF1 rs3729931, HRAS rs45604736, MAPK1 rs2283792, and MAPK1 rs9610417 are associated with gastric cancer.