Associations between OPG and RANKL polymorphisms, vertebral fractures, and abdominal aortic calcification in community-dwelling older subjects: the Sao Paulo Ageing & Health Study (SPAH)

Role of osteoprotegerin rs3102735 gene polymorphism in acute ischemic stroke patients

Background

Ischemic stroke ranks third among leading causes of death and disability. Both endothelial and vascular smooth muscle cells generate osteoprotegerin (OPG). Ischemic stroke and its severity may be enhanced by the OPG rs3102735 gene polymorphism. Our research aims to investigate OPG rs3102735 gene polymorphism role in ischemic stroke risk and to assess its association with stroke severity at presentation and degree of vascular stenosis and evaluate its potential as a predictor of stroke severity. Fifty people with acute ischemic stroke as well as fifty controls were studied. The NIHSS and ASPECTS were utilized to evaluate stroke severity and the infarction size, respectively. All subjects underwent extracranial carotid duplex study and molecular assessment for genotyping of OPG rs3102735) gene polymorphism.

Results

Stroke patients had markedly higher concentrations of OPG in the plasma than controls (311.60 ± 109.48 versus 240.20 ± 75.96 mmol/ml, p = 0.001). The optimal plasma OPG cutoff value for the predicting the occurrence of stroke was determined to be > 250 mmol/ml, the 95% confidence interval (CI) was (0.625–0.843), sensitivity was 68% and specificity was 72%. Ischemic stroke had a significantly different genotype distribution for the OPG rs3102735 gene polymorphism than did controls (36 CC, 13 CT, and 1 TT) versus (28 CC, 15 CT, and 7 TT) respectively. Stroke patients had a significantly greater CC + CT genotype than controls did (P = 0.041), also they had a higher propensity for carrying the C allele than the T allele (P = 0.017). Carotid intima medium thickness and the NIHSS both had positive correlations with OPG serum level (r = 0.39, p = 0.02 and r = 0.4, p = 0.02, respectively), whereas ASPECTS had an inversed correlation (r = − 0.65, p = 0.001).

Conclusions

The current study shows that as an independent risk factor, increased plasma OPG level, may participate in the atherothrombotic ischemic stroke pathophysiology, in addition, genetic variants in the OPG gene (rs3102735) are a separate risk factor for large artery atherosclerosis and plasma OPG level can serve as a biomarker to determine the severity of a stroke.

Vaspin alleviates the lncRNA LEF1-AS1-induced osteogenic differentiation of vascular smooth muscle cells via the Hippo/YAP signaling pathway

Vascular calcification (VC) is closely related to higher cardiovascular mortality and morbidity, and vascular smooth muscle cell (VSMC) switching to osteogenic-like cells is crucial for VC. LncRNA LEF1-AS1 promotes atherosclerosis and dental pulp stem cells calcification, while its role in VC remains unknown. Visceral adipose tissue-derived serine protease inhibitor (vaspin) is an adipokine regulating bone metabolism. However, the relationship between vaspin and VC is still unclear. We aimed to explore the role of LEF1-AS1 on VSMC osteogenic transition, whether vaspin inhibited LEF1-AS1-mediated osteogenic differentiation of VSMCs, and the responsible mechanism. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting analysis indicated that LEF1-AS1 overexpression significantly upregulated osteogenic marker Runt-related transcription factor-2 (RUNX2) level and downregulated VSMC contractile marker α-smooth muscle actin (α-SMA) level. Alizarin red staining, alkaline phosphatase (ALP) staining, ALP activity assay, and calcium content assay also suggested that LEF1-AS1 overexpression promoted calcium deposition in VSMCs. However, vaspin treatment abolished this phenomenon. Mechanistically, LEF1-AS1 markedly decreased phosphorylated YAP level, while vaspin reversed LEF1-AS1-induced phosphorylated YAP decline. Our results revealed that LEF1-AS1 accelerated the osteogenic differentiation of VSMCs by regulating the Hippo/YAP pathway, while vaspin eliminated the LEF1-AS1-meditated VSMCs osteogenic phenotype switch.

Association of TGFB1 rs1800469 and BCMO1 rs6564851 with coronary heart disease and IL1B rs16944 with all-cause mortality in men from the Northern Ireland PRIME study

BACKGROUND

Historically, high levels of morbidity and mortality have been associated with cardiovascular disease in the Northern Ireland population. Previously reported associations between single nucleotide polymorphisms (SNPs) and cardiovascular disease within other populations have not always been consistent.

OBJECTIVE

To investigate associations between 33 SNPs with fatal or non-fatal incident coronary heart disease (CHD) events and all-cause mortality in the Northern Irish participants of the Prospective Epidemiological Study of Myocardial Infarction (PRIME).

METHOD

Phase 2 of the PRIME study prospectively evaluated 2,010 men aged 58-74 years in Northern Ireland for more than 10 years for incident CHD events (myocardial infarction, percutaneous coronary intervention, coronary artery bypass, and cardiac death) and more than 15 years for all-cause mortality. SNPs previously reported in association with cardiovascular outcomes were evaluated against incident CHD events and all-cause mortality using Cox's proportional hazards models adjusted for established cardiovascular disease risk factors.

RESULTS

During the follow-up period, 177 incident CHD events were recorded, and 821 men died. Both BCMO1 rs6564851 (Hazard ratio [HR] = 0.76; 95% confidence intervals [CI]: 0.60-0.96; P = 0.02) and TGFB1 rs1800469 (HR = 1.30; CI: 1.02-1.65; P = 0.04) were significantly associated with incident CHD events in adjusted models. Only IL1B rs16944 was significantly associated with all-cause mortality (HR = 1.18; CI: 1.05-1.33; P = 0.005). No associations remained significant following Bonferonni correction for multiple testing.

CONCLUSION

We report a novel association between BCMO1 rs6564851 and risk of incident CHD events. In addition, TGFB1 rs1800469 and IL1B rs16944 were associated with the risk of incident CHD events and all-cause mortality outcomes respectively, supporting previously reported associations.

Associations of osteoprotegerin (OPG) TNFRSF11B gene polymorphisms with risk of fractures in older adult populations: meta-analysis of genetic and genome-wide association studies

The meta-analysis of osteoprotegerin (OPG) (TNFRSF11B) polymorphisms from genetic association studies and genome-wide association studies was performed in order to test the hypothesis of association between OPG polymorphisms and fracture. The findings showed a significant 13% to 37% protective effect of OPG on fractures in postmenopausal women (PSM) (rs2073618), overall, ≥ 60y and Western subjects (rs3134069 and rs3134070).

PURPOSE

Fractures in older people usually result from compromised bone integrity. The multifactorial aetiology of fractures includes both genetic and environmental factors. Inconsistency of reported associations of osteoprotegerin (OPG) (TNFRSF11B) polymorphisms with fracture in the older adult population warranted a meta-analysis to determine more precise estimates.

METHODS

We searched for all available literature on OPG (TNFRSF11B) and fracture. Four polymorphisms were examined, one exonic (rs2073618) and three intronic (rs3134069, rs3134070 and rs3102735). The first two intron polymorphisms were combined (OPGI: osteoprotegerin intron) on account of complete linkage disequilibrium. Risks were estimated with odds ratios (ORs) and 95% confidence intervals (CIs) using the allele-genotype model that included variant (var), wild-type (wt) and heterozygote (het). Multiple comparisons were Bonferroni-corrected. We used meta-regression to examine sources of heterogeneity. Zero heterogeneity (homogeneity: I² = 0%) and high significance (P^a < 0.00001) were the criteria for strength of evidence. Significant outcomes were subjected to sensitivity analysis and publication bias assessment.

RESULTS

From 13 articles (11 genetic association and two genome-wide), this meta-analysis generated five significant pooled ORs, all indicating reduced risks (ORs 0.44-0.87). Of the five, four highly significant comparisons (P^a ≤ 0.00001-0.002) survived the Bonferroni correction, one in rs2073618 het model of the postmenopausal women (OR 0.87, 95% CI 0.81-0.92, I² = 0%) and the other three in OPGI wt model of the overall analysis, ≥ 60 y and Western subjects (ORs 0.63-0.71, 95% CI 0.47-0.86, I² = 97-99%). These findings were consistent, had high significance and high statistical power and were robust and without evidence of publication bias. Four covariates (year of publication, study quality, fracture type/site and sample size) were the sources of heterogeneity in the OPGI overall outcomes (P^a = 0.0001-0.03).

CONCLUSION

Evidence showed that the OPG (TNFRSF11B) polymorphisms reduced the risk for fracture in older adults, particularly protective among postmenopausal women, ≥ 60 y and Western subjects.

Common Variants of the OPG gene Are Associated with Osteoporosis Risk: A Meta-Analysis

Background: The RANKL/RANK/OPG signaling pathway plays a critical role in osteoclastogenesis and bone remodeling. The associations between sequence variants of the osteoprotegerin (OPG) gene and osteoporosis risk have been widely investigated but remain inconclusive. Objective: We performed a meta-analysis to evaluate the associations between OPG gene variants and osteoporosis risk. Methods: We searched electronic databases and included studies meeting inclusion criteria. The genetic associations of four common OPG variants, A163G, T245G, T950C, and G1181C, with osteoporosis risk were explored. Pooled odds ratios (OR) and 95% confidence intervals (95% CI) were calculated for multiple genetic models. Subgroup analyses including ethnicity, gender, menopausal status, sample size, and control source were also performed. Results: Twenty-six studies comprising 4879 osteoporosis cases and 5708 controls were included. The A163G variant was found to be significantly associated with an increased risk of osteoporosis under both the allelic (G vs. A: OR = 1.45, 95% CI 1.29-1.64, p < 0.001) and dominant models (GG+GA vs. AA: OR = 1.48, 95% CI 1.29-1.70, p < 0.001). Significant associations were also found between the T245G variant and osteoporosis risk. In addition, we observed a reduced risk of osteoporosis in women with the CC genotype at T950C (OR = 0.76, 95% CI 0.64-0.89, p = 0.001) and among Caucasians with the GG or CG genotypes at the G1181C locus (OR = 0.78, 95% CI 0.64-0.94, p = 0.010). In postmenopausal women, only the GG/GA genotypes at the A163G variant were more predisposed to osteoporosis (OR = 1.31, 95% CI 1.00-1.71), whereas CC/CG carriers of G1181C locus may have reduced risk (OR = 0.83, 95% CI 0.66-1.03). Conclusions: Common variants of the OPG gene are associated with osteoporosis risk, especially in the Caucasian population and in the female subgroup. These genetic markers could potentially be used as predictive markers for osteoporosis.

The association of OPG polymorphisms with risk of osteoporotic fractures: A systematic review and meta-analysis

BACKGROUND

Subjects with low bone mineral density and osteoporosis are more likely to suffer osteoporotic fractures during their lifetime. Polymorphisms in osteoprotegerin (OPG) gene are found to be associated with low bone mineral density and osteoporosis risk but their association with fracture risk is inconclusive. Here, we performed a meta-analysis to investigate the relationship between OPG polymorphisms with susceptibility to osteoporotic fractures.

METHODS

Eligible studies investigating the association between common OPG polymorphisms (A164G, T245G, T950C, and G1181C) and risk of osteoporotic fracture were retrieved from PubMed, EMBASE, Web of Science, and the Cochrane Library. Odds ratio (OR) and the 95% confidence interval (CI) were calculated in the allelic, dominant, recessive, and homozygous model. Subgroup analyses of vertebral fractures, Caucasians, and postmenopausal women were also performed.

RESULTS

A total of 14 studies comprising 5459 fracture cases and 9860 non-fracture controls were included. A163G was associated with fracture risk in dominant (OR = 1.29, 95%CI 1.11-1.50), recessive (OR = 1.64, 95%CI 1.10-2.44), and homozygous model (OR = 1.73, 95%CI 1.16-2.59). T245G was significantly correlated with susceptibility to fractures in all genetic models. Subjects with CC genotype of T950C had a reduced risk of fracture compared to those with CT or TT genotypes (OR = 0.81, 95%CI 0.70-0.94, P = .004). Subgroup analysis showed that A163G and T245G but not T950C and G1181C were associated with vertebral fracture risk.

CONCLUSION

OPG A163G and T245G polymorphisms were risk factors of osteoporotic fractures while T950C had a protective role. These polymorphisms can be used as predictive markers of fractures.

Coupled OPG-Fc on Decellularized Aortic Valves by EDC/NHS Attenuates Rat MSCs Calcification In Vitro

Valve calcification commonly damages natural human heart valves and tissue-engineered heart valves (TEHVs), and no ideal intervention is available in clinical practice. It is increasingly considered that osteoprotegerin (OPG) inhibits vascular calcification. Herein we aimed to explore whether free OPG-Fc fusion protein or coupled OPG-Fc on decellularized aortic valves attenuates calcification. Calcification of rat bone marrow-derived mesenchymal stromal cells (MSCs) was induced by osteogenic differentiation media, and the effects of free OPG-Fc or OPG-Fc coupled on the decellularized porcine aortic heart valve leaflet scaffolds by coupling agents 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) on calcification were observed. Mineralization of the extracellular matrix, alkaline phosphatase (ALP) activity, and expression of osteoblastic markers were assessed to determine the calcification kinetics. Our results indicated that the matrix calcium content and the ALP activity, as well as the mRNA expression levels of a bone morphogenetic protein-2 (BMP-2), osteopontin (OPN), and osteocalcin (OC), of the MSCs seeded on plates with free OPG-Fc or on the OPG-Fc-coupled scaffolds decreased compared with their control MSCs without coupled OPG-Fc. The results suggest that both free and immobilized OPG-Fc on the decellularized aortic valve scaffolds by EDC/NHS can attenuate the calcification of MSCs induced by osteogenic differentiation media, implying that OPG-Fc might be a new treatment or prevention strategy for the calcification of natural human heart valves and TEHVs in the future.

Common Variants in OPG Confer Risk to Bone Mineral Density Variation and Osteoporosis Fractures

Although many common variants have been identified for bone mineral density (BMD) and osteoporosis fractures, all the identified risk variants could only explain a small portion of heritability of BMD and osteoporosis fractures. OPG belongs to the tumor necrosis factor receptor superfamily, which plays a crucial role in bone remodeling and is thus a promising candidate gene of osteoporosis. Several studies have explored the association of OPG variants with BMD or osteoporosis fractures, however, the results remain inconsistent among different populations. In the study, we first assessed the relationship between OPG variants and BMD or osteoporosis fractures in our sample size (227 subjects with postmenopausal osteoporosis and 189 controls), and then performed a systematic meta-analysis. Among the nine SNPs genotyped, rs6469804 and rs2073618 showed significant associations with both BMD and osteoporotic fractures, while rs3102735 was only associated with BMD in our samples (P < 0.05). For meta-analyses, data for a total of 12 SNPs were pooled (4725 patients and 37804 controls), and five SNPs, including rs6993813, rs6469804, rs3134070, rs2073618 and rs3102734, showed association with osteoporosis fractures (P < 0.05). On light of the above analysis, we believe that OPG is one promising susceptibility gene of BMD or osteoporotic fractures.