Changes in Noradrenergic Synthesis and Dopamine Beta-Hydroxylase Activity in Response to Oxidative Stress after Iron-induced Brain Injury.

Noradrenaline (NA) levels are altered during the first hours and several days after cortical injury. NA modulates motor functional recovery. The present study investigated whether iron-induced cortical injury modulated noradrenergic synthesis and dopamine beta-hydroxylase (DBH) activity in response to oxidative stress in the brain cortex, pons and cerebellum of the rat. Seventy-eight rats were divided into two groups: (a) the sham group, which received an intracortical injection of a vehicle solution; and (b) the injured group, which received an intracortical injection of ferrous chloride. Motor deficits were evaluated for 20 days post-injury. On the 3rd and 20th days, the rats were euthanized to measure oxidative stress indicators (reactive oxygen species (ROS), reduced glutathione (GSH) and oxidized glutathione (GSSG)) and catecholamines (NA, dopamine (DA)), plus DBH mRNA and protein levels. Our results showed that iron-induced brain cortex injury increased noradrenergic synthesis and DBH activity in the brain cortex, pons and cerebellum at 3 days post-injury, predominantly on the ipsilateral side to the injury, in response to oxidative stress. A compensatory increase in contralateral noradrenergic activity was observed, but without changes in the DBH mRNA and protein levels in the cerebellum and pons. In conclusion, iron-induced cortical injury increased the noradrenergic response in the brain cortex, pons and cerebellum, particularly on the ipsilateral side, accompanied by a compensatory response on the contralateral side. The oxidative stress was countered by antioxidant activity, which favored functional recovery following motor deficits.

Proteomic Biomarkers Associated with Low Bone Mineral Density: A Systematic Review.

Osteoporosis is a globally relevant public health issue. Our study aimed to summarize the knowledge on the proteomic biomarkers for low bone mineral density over the last years. We conducted a systematic review following the PRISMA guidelines; the scoured databases were PubMed, Web of Sciences, Scopus, and EBSCO, from inception to 2 June 2023. A total of 610 relevant studies were identified and 33 were assessed for eligibility. Finally, 29 studies met the criteria for this systematic review. The risk of bias was evaluated using the Joanna Briggs Institute Critical Appraisal Checklist tool. From the studies selected, 154 proteins were associated with changes of bone mineral density, from which only 10 were reported in at least two articles. The protein-protein network analysis indicated potential biomarkers involved in the skeletal system, immune system process, regulation of protein metabolic process, regulation of signaling, transport, cellular component assembly, cell differentiation, hemostasis, and extracellular matrix organization. Mass spectrometry-based proteomic profiling has allowed the discovery of new biomarkers with diagnostic potential. However, it is necessary to compare and validate the potential biomarkers in different populations to determine their association with bone metabolism and evaluate their translation to the clinical management of osteoporosis.

The Involvement of microRNAs in Bone Remodeling Signaling Pathways and Their Role in the Development of Osteoporosis.

Bone remodeling, crucial for maintaining the balance between bone resorption and formation, relies on the coordinated activity of osteoclasts and osteoblasts. During osteoclastogenesis, hematopoietic stem cells (HSCs) differentiate into the osteoclast lineage through the signaling pathways OPG/RANK/RANKL. On the other hand, during osteoblastogenesis, mesenchymal stem cells (MSCs) differentiate into the osteoblast lineage through activation of the signaling pathways TGF-ß/BMP/Wnt. Recent studies have shown that bone remodeling is regulated by post-transcriptional mechanisms including microRNAs (miRNAs). miRNAs are small, single-stranded, noncoding RNAs approximately 22 nucleotides in length. miRNAs can regulate virtually all cellular processes through binding to miRNA-response elements (MRE) at the 3' untranslated region (3'UTR) of the target mRNA. miRNAs are involved in controlling gene expression during osteogenic differentiation through the regulation of key signaling cascades during bone formation and resorption. Alterations of miRNA expression could favor the development of bone disorders, including osteoporosis. This review provides a general description of the miRNAs involved in bone remodeling and their significance in osteoporosis development.

Skin pigmentation related variants in Mexican population and interaction effects on serum 25(OH)D concentration and vitamin D deficiency.

Skin pigmentation is negatively associated with circulating vitamin D (VD) concentration. Therefore, genetic factors involved in skin pigmentation could influence the risk of vitamin D deficiency (VDD). We evaluated the impact genetic variants related to skin pigmentation on VD in Mexican population. This cross-sectional analysis included 848 individuals from the Health Worker Cohort Study (ratio males to females ~ 1:3). Eight genetic variants: rs16891982 (SLC45A2), rs12203592 (IRF4), rs1042602 and rs1126809 (TYR), rs1800404 (OCA2), rs12913832 (HERC2), rs1426654 (SLC24A5), and rs2240751 (MFSD12); involved in skin pigmentation were genotyped. Skin pigmentation was assessed by self-report. Linear and logistic regression were used to assess the association between the variants of interest and VD and VDD, as appropriate. In our study, eight genetic variants were associated with skin pigmentation. A genetic risk score built with the variants rs1426654 and rs224075 was associated with lower VD levels (ß = - 1.38, 95% CI - 2.59, - 0.17, p = 0.025). Nevertheless, when examining gene-gene interactions, we observed that rs2240751 × rs12203592 were associated with VD levels (P interaction = 0.021). Whereas rs2240751 × rs12913832 (P interaction = 0.0001) were associated with VDD. Our results suggest that skin pigmentation-related gene variants are associated with lower VD levels in Mexican population. These results underscore the importance of considering genetic interactions when assessing the impact of genetic polymorphisms on VD levels.

Interaction between MARK3 (rs11623869), PLCB4 (rs6086746) and GEMIN2 (rs2277458) variants with bone mineral density and serum 25-hidroxivitamin D levels in Mexican Mestizo women.

Introduction: Understanding the genetic factors contributing to variations in bone mineral density (BMD) and vitamin D could provide valuable insights into the pathogenesis of osteoporosis. This study aimed to evaluate the association of single nucleotide variants in MARK3 (rs11623869), PLCB4 (rs6086746), and GEMIN2 (rs2277458) with BMD in Mexican women. Methods: The gene-gene interaction was evaluated in these variants in serum 25(OH)D levels and BMD. A genetic risk score (GRS) was created on the basis of the three genetic variants. Genotyping was performed using predesigned TaqMan assays. Results: A significant association was found between the rs6086746-A variant and BMD at the total hip, femoral neck, and lumbar spine, in women aged 45 years or older. However, no association was observed between the variants rs11623869 and rs2277458. The rs11623869 × rs2277458 interaction was associated with total hip (p=0.002) and femoral neck BMD (p=0.013). Similarly, for vitamin D levels, we observed an interaction between the variants rs6086746 × rs2277458 (p=0.021). GRS revealed a significant association with total hip BMD (p trend=0.003) and femoral neck BMD (p trend=0.006), as well as increased vitamin D levels (p trend=0.0003). These findings provide evidence of the individual and joint effect of the MARK3, PLCB4, and GEMIN2 variants on BMD and serum vitamin D levels in Mexican women. Discussion: This knowledge could help to elucidate the interaction mechanism between BMD-related genetic variants and 25OHD, contributing to the determination of the pathogenesis of osteoporosis and its potential implications during early interventions.

Environmental and Genetic Risk Factors in Developmental Dysplasia of the Hip for Early Detection of the Affected Population.

Diagnosis of developmental dysplasia of the hip (DDH) mostly relies on physical examination and ultrasound, and both methods are operator-dependent. Late detection can lead to complications in young adults. Current evidence supports the involvement of environmental and genetic factors, such as single nucleotide variants (SNVs). Incorporating genetic factors into diagnostic methods would be useful for implementing early detection and management of affected individuals. Our aim was to analyze environmental factors and SNVs in DDH patients. We included 287 DDH cases and 284 controls. Logistic regression demonstrated an association for sex (OR 9.85, 95% CI 5.55-17.46, p = 0.0001), family history (OR 2.4, 95% CI 1.2-4.5, p = 0.006), fetal presentation (OR 3.19, 95% CI 1.55-6.54, p = 0.002), and oligohydramnios (OR 2.74, 95%CI 1.12-6.70, p = 0.026). A model predicting the risk of DDH including these variables showed sensitivity, specificity, PPV, and NPV of 0.91, 0.53, 0.74, and 0.80 respectively. The SNV rs1800470 in TGFB1 showed an association when adjusted for covariables, OR 0.49 (95% CI 0.27-0.90), p = 0.02. When rs1800470 was included in the equation, sensitivity, specificity, PPV and NPV were 0.90, 0.61, 0.84, and 0.73, respectively. Incorporating no-operator dependent variables and SNVs in detection methods could be useful for establishing uniform clinical guidelines and optimizing health resources.

Label-free quantitative proteomics in serum reveals candidate biomarkers associated with low bone mineral density in Mexican postmenopausal women.

Postmenopausal osteoporosis is a public health problem leading to an increased risk of fractures, negatively impacting women's health. The absence of sensitive and specific biomarkers for early detection of osteoporosis represents a substantial challenge for improving patient management. Herein, we aimed to identify potential candidate proteins associated with low bone mineral density (BMD) in postmenopausal women from the Mexican population. Serum samples from postmenopausal women (40 with normal BMD, 40 with osteopenia (OS), and 20 with osteoporosis (OP)) were analyzed by label-free LC-MS/MS quantitative proteomics. Proteome profiling revealed significant differences between the OS and OP groups compared to individuals with normal BMD. A quantitative comparison of proteins between groups indicated 454 differentially expressed proteins (DEPs). Compared to normal BMD, 14 and 214 DEPs were found in OS and OP groups, respectively, while 226 DEPs were identified between OS and OP groups. The protein-protein interaction and enrichment analysis of DEPs were closely linked to the bone mineral content, skeletal morphology, and immune response activation. Based on their role in bone metabolism, a panel of 12 candidate biomarkers was selected, of which 1 DEP (RYR1) was found upregulated in the OS and OP groups, 8 DEPs (APOA1, SHBG, FETB, MASP1, PTK2B, KNG1, GSN, and B2M) were upregulated in OP and 3 DEPs (APOA2, RYR3, and HBD) were downregulated in OS or OP. The proteomic analysis described here may help discover new and potentially non-invasive biomarkers for the early diagnosis of osteoporosis in postmenopausal women.

Association Study between Antioxidant Nutrient Intake and Low Bone Mineral Density with Oxidative Stress-Single Nucleotide Variants: GPX1 (rs1050450 and rs17650792), SOD2 (rs4880) and CAT (rs769217) in Mexican Women.

Oxidative stress is essential in developing multiple bone metabolism diseases, including osteoporosis. Single-nucleotide variants (SNVs) have been associated with oxidative stress, promoting an imbalance between the production of reactive oxygen species and the ability to neutralize them, and it has been reported that antioxidant nutrient intake can influence bone mineral density (BMD). This work reports the association between oxidative stress-related SNVs (GPX1-rs1050450, rs17650792, SOD2-rs4880, and CAT-rs769217), BMD, and antioxidant nutrient intake. The study included 1269 Mexican women from the Health Workers Cohort Study. Genotyping was performed using predesigned TaqMan assays. Dietary data were collected using a 116-item semi-quantitative food frequency questionnaire. A dietary antioxidant quality score (DAQS) was used to estimate antioxidant-nutrient intake. Association analysis was estimated via linear, logistic, or quantile regression models. The results showed an association of the rs1050450-A and rs17650792-A alleles with femoral neck BMD (p = 0.038 and p = 0.017, respectively) and the SNV rs4880-A allele with total hip BMD (p = 0.026) in respondents aged 45 years or older. In addition, antioxidant-nutrient intake was associated with the rs4880-GG genotype, being significant for fiber (p = 0.007), riboflavin (p = 0.005), vitamin B6 (p = 0.034), and vitamin D (p = 0.002). The study showed an association between oxidative stress-related SNVs, BMD, and antioxidant-nutrient intake in Mexican women. Therefore, treatments for low BMD could be developed based on antioxidant supplementation.

Diagnostic Performance of the Tear Meniscus Osmolarity Measurement for Dry Eye Disease in Rheumatoid Arthritis Patients.

BACKGROUND: The aim of our study was to evaluate the diagnostic capacity of the tear meniscus osmolarity measurement for dry eye disease (DED) in patients with rheumatoid arthritis (RA), using a portable osmometer based on electrical impedance and an integrated circuit technology (TearLab® (Escondido, CA, USA)). METHODS: We included 101 RA patients, 81 patients with DED and 20 without DED (controls). We measured tear osmolarity and assessed other clinical diagnostic tests as suggested by the TFOS DEWS II composite reference standard diagnostic criteria for DED using Ocular Surface Disease Index (OSDI), Five-item Dry Eye Questionnaire (DEQ-5), fluorescein tear break-up time (F-TUBT), ocular surface staining (SICCA score), and other clinical parameters to classify DED subtypes. We analyzed the agreement between osmolarity and the TFOS DEWS II composite reference standard for DED diagnosis. We conducted receiver operating characteristic (ROC) curve analyses using the DED variable and its subtypes as dependent variables and the continuous variable for osmolarity or the inter-eye difference in osmolarity as independent variable. Sensitivity, specificity, and area under the curve for all potential cut-off points were obtained and reported from ROC curves. RESULTS: We found that tear meniscus osmolarity had a low diagnostic capacity for DED (AUC = 0.57). Tear meniscus osmolarity measurement had a sensitivity of 35% and a specificity of 80% with a kappa level of agreement of 0.08 compared to the TFOS DEWS II composite reference standard. The low diagnostic capacity of the tear meniscus osmolarity was similar for aqueous-deficient DED and for evaporative DED, being only fair for severe DED with a 57% sensitivity and 80% specificity and a kappa level of agreement of 0.36. CONCLUSIONS: Our findings suggest that in patients with RA, tear meniscus osmolarity measured by the TearLab® showed low sensitivity, low specificity, and limited agreement with the TFOS DEWS II composite reference standard for DED diagnosis.

Administration of Tamoxifen Can Regulate Changes in Gene Expression during the Acute Phase of Traumatic Spinal Cord Injury.

Traumatic spinal cord injury (SCI) causes irreversible damage leading to incapacity. Molecular mechanisms underlying SCI damage are not fully understood, preventing the development of novel therapies. Tamoxifen (TMX) has emerged as a promising therapy. Our aim was to identify transcriptome changes in the acute phase of SCI and the effect of Tamoxifen on those changes in a rat model of SCI. Four groups were considered: (1) Non-injured without TMX (Sham/TMX-), (2) Non-injured with TMX (Sham/TMX+), (3) injured without TMX (SCI/TMX-), and (4) injured with TMX (SCI/TMX+). Tamoxifen was administered intraperitoneally 30 min after injury, and spinal cord tissues were collected 24 h after injury. Clariom S Assays Array was used for transcriptome analysis. After comparing Sham/TMX- versus SCI/TMX-, 708 genes showed differential expression. The enriched pathways were the SCI pathway and pathways related to the inflammatory response. When comparing SCI/TMX- versus SCI/TMX+, only 30 genes showed differential expression, with no pathways enriched. Our results showed differential expression of genes related to the inflammatory response after SCI, and Tamoxifen seems to regulate gene expression changes in Ccr2 and Mmp12. Our study contributes data regarding the potential value of tamoxifen as a therapeutic resource for traumatic SCI during the acute phase.

Association of the EPAS1 rs7557402 Polymorphism with Hemodynamically Significant Patent Ductus Arteriosus Closure Failure in Premature Newborns under Pharmacological Treatment with Ibuprofen.

Patent ductus arteriosus (PDA) is frequent in preterm newborns, and its incidence is inversely associated with the degree of prematurity. The first choice of pharmacological treatment is ibuprofen. Several genes, including EPAS1, have been proposed as probable markers associated with a genetic predisposition for the development of PDA in preterm infants. EPAS 1 NG_016000.1:g.84131C>G or rs7557402 has been reported to be probably benign and associated with familial erythrocytosis by the Illumina Clinical Services Laboratory. Other variants of EPAS1 have been previously reported to be benign for familial erythrocytosis because they decrease gene function and are positive for familial erythrocytosis because the overexpression of EPAS1 is a key factor in uncontrolled erythrocyte proliferation. However, this could be inconvenient for ductal closure, since for this process to occur, cell proliferation, migration, and differentiation should take place, and a decrease in EPAS1 gene activity would negatively affect these processes. Single-nucleotide polymorphisms (SNPs) in EPAS1 and TFAP2B genes were searched with high-resolution melting and Sanger sequencing in blood samples of preterm infants with hemodynamically significant PDA treated with ibuprofen at the National Institute of Perinatology. The variant rs7557402, present in the EPAS1 gene eighth intron, was associated with a decreased response to treatment (p = 0.007, OR = 3.53). The SNP rs7557402 was associated with an increased risk of pharmacological treatment failure. A probable mechanism involved could be the decreased activity of the product of the EPAS1 gene.

Blood Type Associated with the Risk of COVID-19 Infection in Pregnant Women.

COVID-19 forced us to investigate risk factors to provide the best medical attention, especially in vulnerable groups, such as pregnant patients. Studies in other populations have analyzed blood groups in relation to infection, complications, and death. The present study aimed to analyze the association of blood groups with the risk of infection and complications in pregnant women and newborns from the Mexican-Mestizo population. We studied 1906 individuals. Quantitative variables were analyzed through the Student's t-test. Categorical variables were analyzed through Pearson's chi-square test, and logistic regression was used to analyze the association between categorical variables and outcomes. No significant association was observed between blood groups and infection risk. Individuals with the AB blood type are at higher risk for developing severe disease, although blood groups do not seem to be involved in the risk of SARS-CoV-2 infection. However, the AB blood group could be considered a risk factor for developing severe COVID-19 in the Mexican population.

Genetic polymorphisms rs1800871 and rs1800872 of IL-10 gene are associated with dengue infection, especially with serotype 1 and DwoWS in Mexican population.

INTRODUCTION: Dengue infection is generated by a complex interaction between DENV (Dengue Virus) and the host's immune response. Interleukin-10 is an immunoregulatory cytokine during DENV infection. The objective of this study was to investigate whether genetic variants in IL-10 could be useful as a predictive and susceptibility marker in the prognosis of DENV infection, particularly with serotype 1, and in participants with dengue without warning signs. MATERIAL AND METHODS: A study of cases (n = 365) and controls (n = 364) was carried out. Genotyping was performed by real-time PCR using TaqMan probes. Sample size power was calculated using Quanto software RESULTS: This is the first report showing the independent association of the T allele of rs1800871 (P = 0.023) and the A allele of rs1800872 (P = 0.010) with the risk of dengue infection. Statistical analysis established the genotypic association of IL-10 SNPs with DENV infection under different inheritance models. Our results also showed the association of the CC, TC, and CA haplotypes (P = 0.0064, P = 0.0032, and P = 0.0010 respectively) with infection. Furthermore, both polymorphic sites were associated with the risk of DwoWS and serotype 1 (Den-1) under different inheritance models. Finally, under the dominant model, we identified a positive correlation between IL-10 levels vs. IFN-γ and IL-8. CONCLUSION: Our results show the first independent association of the T and A alleles of the polymorphic sites rs1800871 and rs1800872, with dengue infection, particularly with Den-1, and in participants with DwoWs.

Interaction between SIDT2 and ABCA1 Variants with Nutrients on HDL-c Levels in Mexican Adults.

Previous studies have reported that the SIDT2 and ABCA1 genes are involved in lipid metabolism. We aimed to analyze the association-the gene x gene interaction between rs17120425 and rs1784042 on SIDT2 and rs9282541 on ABCA1 and their diet interaction on the HDL-c serum levels-in a cohort of 1982 Mexican adults from the Health Workers Cohort Study. Demographic and clinical data were collected through a structured questionnaire and standardized procedures. Genotyping was performed using a predesigned TaqMan assay. The associations and interactions of interest were estimated using linear and logistic regression. Carriers of the rs17120425-A and rs1784042-A alleles had slightly higher blood HDL-c levels compared to the non-carriers. In contrast, rs9282541-A was associated with low blood HDL-c levels (OR = 1.34, p = 0.013). The rs1784042 x rs9282541 interaction was associated with high blood HDL-c levels (p = 3.4 × 10-4). Premenopausal women who carried at least one rs17120425-A allele and consumed high dietary fat, protein, monounsaturated, or polyunsaturated fatty acids levels had higher HDL-c levels than the non-carriers. These results support the association between the genetic variants on SIDT2 and ABCA1 with HDL-c levels and suggest gene-gene and gene-diet interactions over HDL-c concentrations in Mexican adults. Our findings could be a platform for developing clinical and dietary strategies for improving the health of the Mexican population.

Unraveling the role of relative telomere length and CAG expansion on initial symptoms of juvenile Huntington disease.

BACKGROUND AND PURPOSE: Juvenile-onset Huntington disease (JHD) is defined when symptoms initiate before 20 years of age. Mechanisms explaining differences between juvenile and adult onset are not fully understood. Our aim was to analyze the distribution of initial symptoms in a cohort of JHD patients and to explore its relationship with CAG expansion and relative telomere length (RTL). METHODS: A total of 84 JHD patients and 54 neurologically healthy age and sex matched individuals were recruited. CAG length was measured by southern blot or triplet repeat primed polymerase chain reaction. RTL was measured using the Cawthon method. RESULTS: Psychiatric symptoms were most frequent when considering the entire cohort. When divided into onset before or after 10 years, cognitive symptoms were more frequent in the youngest, whilst in the older group psychiatric symptoms prevailed. Motor symptoms were rare in the youngest and epilepsy was observed only in this group as well as a larger CAG expansion. RTL analysis revealed shorter telomeres in JHD patients compared to controls. This difference is not influenced by age, initial symptoms, time of disease or CAG expansion. CONCLUSIONS: To the best of our knowledge this is the largest cohort of JHD patients reported. Psychiatric manifestations deserve special attention when JHD is suspected and epilepsy is especially important in the youngest patients. Initial symptoms seem to be influenced by CAG expansion and therefore age of onset. RTL is significantly reduced in JHD patients which can influence the characteristic neurodegeneration of JHD and contribute to the clinical discrepancy between adult and juvenile forms of Huntington disease.

miR-145, miR-92a and miR-375 Show Differential Expression in Serum from Patients with Diabetic Retinopathies.

Diabetic retinopathies are important disabling conditions. Micro-RNAs (miRNAs) are regulators of gene expression and diseases can change their expression. Our aim was to analyze the expression of miRNAs in serum and vitreous samples from patients with diabetic retinopathies. The following groups and number of individuals were included: proliferative diabetic retinopathy (PDR) (n = 16), diabetic macular edema (DME) (n = 17), and idiopathic epiretinal membrane (IEM) as non-diabetic controls (n = 23). The initial miRNA expression was explored using TaqMan low-density arrays (TLDAs) with subsequent validation through a quantitative polymerase chain reaction (qPCR). Target genes were identified through bioinformatic tools for enrichment analysis. The TLDAs revealed the following miRNAs with differential expression in terms of PDR vs. IEM: miR-320a-3p, miR-92a-3p, and miR-375-3p in the serum, with miR-541-5p and miR-223-5p in the vitreous samples. DME vs IEM: miR-486-5p, miR-145-5p, miR-197-3p, and miR-125b-5p in the serum, and miR-212-3p in vitreous samples. PDR vs. DME: miR-486-5p, miR-100-5p, miR-328-3p, miR-660-5p, and miR-145 in the serum and none in the vitreous samples. Validation was confirmed only for miR-145, miR-92a, and miR-375 in the serum. The relevant enriched pathways for these three validated miRNAs, miR-145, miR-92a, and miR-375 were the vascular endothelial growth factor and its receptor, hepatocyte growth factor receptor, epidermal growth factor, focal adhesion, and phosphoinositide 3-kinase. Our results support the involvement of miRNAs in the pathophysiology of diabetic retinopathies and reinforce their potential as biomarkers or therapeutic resources.

Uric Acid Levels Are Associated with Bone Mineral Density in Mexican Populations: A Longitudinal Study.

Background: Inconsistent epidemiological evidence between uric acid (UA) and bone mineral density (BMD) has been observed. Therefore, we evaluated the association between UA and BMD in Mexican adults. Methods: This analysis was conducted on 1423 participants from the Health Workers Cohort Study. We explored cross-sectional associations using linear regression and longitudinal associations using fixed-effects linear regression by sex and age groups (<45 and ≥45 years). Results: In females <45 years old, the cross-sectional analysis showed that UA levels were positively associated with total hip BMD. However, in the longitudinal analysis, we observed a negative association with the femoral neck and lumbar spine BMD. In contrast, in males <45 years old, we found an increase in total hip and femoral neck BMD in the groups with high levels of UA in the longitudinal association. On the other hand, in females ≥45 years old, we observed a longitudinal association between UA and loss of BMD at different sites. We did not observe an association between UA levels and BMD in males ≥45 years old. Conclusions: Our results suggest higher serum UA levels are associated with low BMD at different skeletal sites in Mexican females. Further studies are needed to delineate the underlying mechanisms behind this observation.

Unravelling the Contribution of the rs7041 and rs4588 Polymorphisms of the GC Gene and Serum VDBP Levels for Developing Metabolic Syndrome in the Mexican Population.

Metabolic syndrome (MetS) is a multifactorial disorder integrated by a constellation of cardiovascular risk factors. The genetic and environmental determinants of MetS are not fully elucidated. This study investigated the association of two common single nucleotide polymorphisms (SNPs) on GC, rs7041 and rs4588, derived haplotypes, and serum vitamin D binding protein (VDBP) levels with the susceptibility to suffer MetS in Mexican adults. We included 1924 individuals; clinical and biochemical data were obtained through standard methods. Genotyping was performed through predesigned TaqMan assays. Logistic regression models were used to assess the associations of interest. Prevalence of MetS was 52.9% in the whole population, being more frequent in women. We observed that some association results differed between sexes. The GG genotype of the rs7041 was associated with increased odds of MetS in women. For the rs4588, the CA genotype had a protective effect against MetS in women. The haplotype GC2 was associated with reduced odds for MetS and some of its components in women. Our data suggest that VDBP serum levels were influenced by genotypes/haplotypes and this interplay seems to influence the risk of MetS. Our data provide reliable evidence regarding the association of GC polymorphisms with MetS risk in Mexican women.

Dietary inflammatory index and bone mineral density in Mexican population.

Dietary inflammatory index has been associated with bone loss. In this longitudinal study, we reported that changes in dietary inflammatory index were associated with a reduction in bone mineral density of the total hip and femoral neck in males and females ≥ 45 years, but not in individuals < 45 years. PURPOSE: Previous studies have suggested that an inflammatory environment can affect bone mineral density (BMD). However, most of the studies have been done in postmenopausal women. Thus, longitudinal studies in different age groups and sex are necessary to evaluate the longitudinal association between dietary inflammatory index (DII) and BMD in Mexican adults. METHODS: A total of 1,486 participants of the Health Workers Cohort Study were included in this study. The DII was estimated with data retrieved through a semi-quantitative food frequency questionnaire. Total hip, femoral neck, and lumbar spine BMD were measured by dual-energy X-ray absorptiometry. Linear regression models for cross-sectional associations and fixed effects linear regression models for longitudinal association were estimated, and both models were stratified by sex and age groups (< 45 and ≥ 45 years). RESULTS: We did not observe cross-sectional associations between DII and the different BMD sites at baseline. In contrast, women and men ≥ 45 years in the 25th quartile of changes in DII were associated with a gain of 0.067 g/cm2 and 0.062 g/cm2 of total hip BMD, while those in the 75th quartile of DII was associated with a reduction of - 0.108 g/cm2 and - 0.100 g/cm2, respectively. These results were similar for femoral neck BMD in women. In contrast, we did not observe association with femoral neck BMD in men. We did not observe statistically significant changes for lumbar spine BMD. CONCLUSION: Our data suggest that changes in the DII score are associated with changes in total hip and femoral neck BMD among Mexican population.

Common variant rs6564851 near the beta-carotene oxygenase 1 gene is associated with plasma triglycerides levels in middle-aged Mexican men adults.

Dyslipidemias have been linked to an increased risk of adverse health outcomes, including cardiovascular disease, type 2 diabetes, and the metabolic syndrome. Recent reports have associated the beta-carotene oxygenase 1 (BCO1) gene with lipid metabolism, mainly reducing total cholesterol and increasing high-density lipoprotein-cholesterol (HDL-C) concentrations. The hypothesis of this study was that the variant rs6564851 near the BCO1 gene is associated positively with the lipid profile in middle-aged Mexican adults. This study included 1441 Mexicans older than 40 years of age from the Health Workers Cohort Study (HWCS). Genotyping was conducted using a predesigned TaqMan assay. Lipid profile was measured with standardized procedures. Our results showed that the men carrying at least 1 T allele had higher serum triglyceride concentrations than GG homozygous (GG: 146.5 mg/dL; GT: 175 mg/dL; and TT: 184 mg/dL; P = .008). The variant rs6564851 showed a risk associated with the serum triglyceride concentrations(odds ratio [OR], 2.77; P = .002) only in the male group. However, we did not observe significant differences in the serum total cholesterol, HDL-C, and low-density lipoprotein-cholesterol concentrations in both sexes. Our study provides evidence that the variant rs6564851 is negatively associated with the triglyceride concentrations in middle-aged Mexican male adults in the HWCS. This knowledge can be the basis for developing effective nutritional strategies according to sex and the genetic variants present in an individual. Further studies in independent populations are required to validate these findings and determine the mechanism of the association sex dependent.