Cross-sectional relations of whole-blood miRNA expression levels and hand grip strength in a community sample

Pharmacogenetic and microRNA mechanisms of beta blocker use on bone

Motivated by studies showing an association between beta blocker (BB) use and positive bone outcomes, a pilot randomized control trial was performed at the Mayo Clinic which randomized postmenopausal women to placebo, propranolol (40 or 80 mg twice daily), atenolol (50 mg/d), or nebivolol (5 mg/d) to determine changes in bone turnover markers (BTMs) and in BMD over 20 wk. Pharmacogenetic effects and microRNA-mediated mechanisms involving beta adrenergic receptor and related genes have previously been found. We sought to validate these effects and discover new candidates in an ancillary study to the pilot clinical trial. We genotyped all participants and performed microRNA (miRNA) sequencing at baseline and at 20 wk for 24 participants from the atenolol or placebo groups. We discovered several variants in ADRB1, ADRB2, and HDAC4 which showed significant pharmacogenetic effects with BMD at multiple sites and with BTMs. Our miRNA results showed a significant treatment effect for miR-19a-3p over time with atenolol use in the low-responder group compared to placebo. Overall, the longitudinal miRNA analysis showed a large number of miRNAs which were up-regulated over the trial in the low responders but not the high responders compared to placebo, of which miR-19a-3p was one example. Finally, we compared the response to atenolol treatment for cardiovascular traits (pulse and blood pressure) with the response for the bone resorption marker, C-terminal telopeptide, and found a largely independent effect. Our results have implications for personalized therapy and for understanding mechanisms of BB treatment effect on bone.

Biomarkers of the Physical Function Mobility Domains Among Patients Hospitalized in Internal Medicine

Hospitalized patients in internal medicine have an increased risk of low physical reserve which further declines during the hospital stay. The diagnosis requires bed-side testing of functional domains or more complex investigations of the muscle mass. Clinically useful biomarkers of functional status are needed, thus we aimed to explore the potential of microRNAs. Among hospitalized patients, we recorded the basic demographics, anthropometrics, nutritional status, and physical function domains: hand-grip strength (HGS, abnormal values M<30 kg, W<20 kg), balance (<30 s), chair-stands speed (CHSS<0.5/s) and gait speed (GS<0.8 m/s). A panel of five micro-RNAs (miRNA 1, miRNA 133a, miRNA 133b, miRNA 29a, miRNA 29b) and basic blood biochemistry and vitamin D values were recorded. We enrolled 80 patients (M40, W40), with a mean age of 68.8±8.4 years. Obesity was observed in 27.5 % and 30 %, low HGS and low CHSS in 65.0, 77.5 %, and 80, 90 % of men and women respectively. The median hospital stay was 6.5 days. MiRNA29a and miRNA29b have the strongest correlation with the triceps skinfold (miRNA 29b, r=0.377, p=0.0006) and CHSS (miRNA 29a, r=0.262, p=0.02). MiRNA 29a, miRNA 29b and 133a levels were significantly higher in patients with CHSS<0.5/s. Other anthropometric parameters, mobility domains, or vitamin D did not correlate. All miRNAs except of miRNA 1, could predict low CHSS (miRNA29b, AUROC=0.736 CI 0.56-0.91, p=0.01), particularly in patients with low HGS (miRNA 29b, AUROC=0.928 CI 0.83-0.98). Among hospitalized patients in internal medicine, low functional status was frequent. MicroRNAs were fair biomarkers of the antigravity domain, but not other domains. Larger studies with clinical endpoints are needed.

Biomarkers of the Physical Function Mobility Domains Among Patients Hospitalized in Internal Medicine

Hospitalized patients in internal medicine have an increased risk of low physical reserve which further declines during the hospital stay. The diagnosis requires bed-side testing of functional domains or more complex investigations of the muscle mass. Clinically useful biomarkers of functional status are needed, thus we aimed to explore the potential of microRNAs. Among hospitalized patients, we recorded the basic demographics, anthropometrics, nutritional status, and physical function domains: hand-grip strength (HGS, abnormal values M<30 kg, W<20 kg), balance (<30 s), chair-stands speed (CHSS<0.5/s) and gait speed (GS<0.8 m/s). A panel of five micro-RNAs (miRNA 1, miRNA 133a, miRNA 133b, miRNA 29a, miRNA 29b) and basic blood biochemistry and vitamin D values were recorded. We enrolled 80 patients (M40, W40), with a mean age of 68.8±8.4 years. Obesity was observed in 27.5 % and 30 %, low HGS and low CHSS in 65.0, 77.5 %, and 80, 90 % of men and women respectively. The median hospital stay was 6.5 days. MiRNA29a and miRNA29b have the strongest correlation with the triceps skinfold (miRNA 29b, r=0.377, p=0.0006) and CHSS (miRNA 29a, r=0.262, p=0.02). MiRNA 29a, miRNA 29b and 133a levels were significantly higher in patients with CHSS<0.5/s. Other anthropometric parameters, mobility domains, or vitamin D did not correlate. All miRNAs except of miRNA 1, could predict low CHSS (miRNA29b, AUROC=0.736 CI 0.56-0.91, p=0.01), particularly in patients with low HGS (miRNA 29b, AUROC=0.928 CI 0.83-0.98). Among hospitalized patients in internal medicine, low functional status was frequent. MicroRNAs were fair biomarkers of the antigravity domain, but not other domains. Larger studies with clinical endpoints are needed.

Osteoporosis, fracture, osteoarthritis & sarcopenia: A systematic review of circulating microRNA association

Circulating microRNAs (c-miRs) show promise as biomarkers. This systematic review explores their potential association with age-related fracture/osteoporosis (OP), osteoarthritis (OA) and sarcopenia (SP), as well as cross-disease association. Most overlap occurred between OA and OP, suggesting potentially shared microRNA activity. There was little agreement in results across studies. Few reported receiver operating characteristic analysis (ROC) and many identified significant dysregulation in disease, but direction of effect was commonly conflicting. c-miRs with most evidence for consistency in dysregulation included miR-146a, miR-155 and miR-98 for OA (upregulated). Area under the curve (AUC) for miR-146a biomarker performance was AUC 0.92, p = 0.028. miR-125b (AUC 0.76-0.89), miR-100, miR-148a and miR-24 were consistently upregulated in OP. Insufficient evidence exists for c-miRs in SP. Study quality was typically rated intermediate/high risk of bias. Wide study heterogeneity meant meta-analysis was not possible. We provide detailed critique and recommendations for future approaches in c-miR analyses based on this review.

Pharmacogenomic Effects of β-Blocker Use on Femoral Neck Bone Mineral Density

CONTEXT

Recent studies have shown that β-blocker (BB) users have a decreased risk of fracture and higher bone mineral density (BMD) compared to nonusers, likely due to the suppression of adrenergic signaling in osteoblasts, leading to increased BMD. There is also variability in the effect size of BB use on BMD in humans, which may be due to pharmacogenomic effects.

OBJECTIVE

To investigate potential single-nucleotide variations (SNVs) associated with the effect of BB use on femoral neck BMD, we performed a cross-sectional analysis using clinical data, dual-energy x-ray absorptiometry, and genetic data from the Framingham Heart Study's (FHS) Offspring Cohort. We then sought to validate our top 4 genetic findings using data from the Rotterdam Study, the BPROOF Study, the Malta Osteoporosis Fracture Study (MOFS), and the Hertfordshire Cohort Study.

METHODS

We used sex-stratified linear mixed models to determine SNVs that had a significant interaction effect with BB use on femoral neck (FN) BMD across 11 gene regions. We also evaluated the association of our top SNVs from the FHS with microRNA (miRNA) expression in blood and identified potential miRNA-mediated mechanisms by which these SNVs may affect FN BMD.

RESULTS

One variation (rs11124190 in HDAC4) was validated in females using data from the Rotterdam Study, while another (rs12414657 in ADRB1) was validated in females using data from the MOFS. We performed an exploratory meta-analysis of all 5 studies for these variations, which further validated our findings.

CONCLUSION

This analysis provides a starting point for investigating the pharmacogenomic effects of BB use on BMD measures.

Higher Hand Grip Strength Is Associated With Greater Radius Bone Size and Strength in Older Men and Women: The Framingham Osteoporosis Study

Mechanical loading by muscles elicits anabolic responses from bone, thus age‐related declines in muscle strength may contribute to bone fragility in older adults. We used high‐resolution peripheral quantitative computed tomography (HR‐pQCT) to determine the association between grip strength and distal radius bone density, size, morphology, and microarchitecture, as well as bone strength estimated by micro–finite element analysis (μFEA), among older men and women. Participants included 508 men and 651 women participating in the Framingham Offspring Study with grip strength measured in 2011–2014 and HR‐pQCT scanning in 2012–2015. Separately for men and women, analysis of covariance was used to compare HR‐pQCT measures among grip strength quartiles and to test for linear trends, adjusting for age, height, weight, smoking, and physical activity. Mean age was 70 years (range, 50–95 years), and men had higher mean grip strength than the women (37 kg vs. 21 kg). Bone strength estimated by μFEA‐calculated failure load was higher with greater grip strength in both men (p < 0.01) and women (p = 0.04). Higher grip strength was associated with larger cross‐sectional area in both men and women (p < 0.01), with differences in area of 6% and 11% between the lowest to highest grip strength quartiles in men and women, respectively. Cortical thickness was positively associated with grip strength among men only (p = 0.03). Grip strength was not associated with volumetric BMD (vBMD) in men. Conversely, there was a trend for lower total vBMD with higher grip strength among women (p = 0.02), though pairwise comparisons did not reveal any statistically significant differences in total vBMD among grip strength quartiles. Bone microarchitecture (cortical porosity, trabecular thickness, trabecular number) was not associated with grip strength in either men or women. Our findings suggest that the positive association between hand grip strength and distal radius bone strength may be driven primarily by bone size. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

miRNA Mechanisms Underlying the Association of Beta Blocker Use and Bone Mineral Density

Osteoporosis is a debilitating and costly disease that causes fractures in 33% of women and 20% of men over the age of 50 years. Recent studies have shown that beta blocker (BB) users have higher bone mineral density (BMD) and decreased risk of fracture compared with non-users. The mechanism underlying this association is thought to be due to suppression of adrenergic signaling in osteoblasts, which leads to increased BMD in rodent models; however, the mechanism in humans is unknown. Also, several miRNAs are associated with adrenergic signaling and BMD in separate studies. To investigate potential miRNA mechanisms, we performed a cross-sectional analysis using clinical data, dual-energy X-ray absorptiometry (DXA) scans, and miRNA and mRNA profiling of whole blood from the Framingham Study's Offspring Cohort. We found nine miRNAs associated with BB use and increased BMD. In parallel network analyses, we discovered a subnetwork associated with BMD and BB use containing two of these nine miRNAs, miR-19a-3p and miR-186-5p. To strengthen this finding, we showed that these two miRNAs had significantly higher expression in individuals without incident fracture compared with those with fracture in an external data set. We also noted a similar trend in association between these miRNA and Z-score as calculated from heel ultrasound measures in two external cohorts (SOS-Hip and SHIP-TREND). Because miR-19a directly targets the ADRB1 mRNA transcript, we propose BB use may downregulate ADRB1 expression in osteoblasts through increased miR-19a-3p expression. We used enrichment analysis of miRNA targets to find potential indirect effects through insulin and parathyroid hormone signaling. This analysis provides a starting point for delineating the role of miRNA on the association between BB use and BMD. © 2020 American Society for Bone and Mineral Research (ASBMR).

Bacteria-related changes in host DNA methylation and the risk for CRC

Colorectal cancer (CRC) is the second most common cause of cancer deaths in men and women combined. Colon-tumor growth is multistage and the result of the accumulation of spontaneous mutations and epigenetic events that silence tumor-suppressor genes and activate oncogenes. Environmental factors are primary contributors to these somatic gene alterations, which account for the increase in incidence of CRC in western countries. In recent decades, gut microbiota and their metabolites have been recognized as essential contributing factors to CRC, and now serve as biomarkers for the diagnosis and prognosis of CRC. In the present review, we highlight holistic approaches to understanding how gut microbiota contributes to CRC. We particularly focus herein on bacteria-related changes in host DNA methylation and the risk for CRC.

Epigenome-wide exploratory study of monozygotic twins suggests differentially methylated regions to associate with hand grip strength

Hand grip strength is a measure of muscular strength and is used to study age-related loss of physical capacity. In order to explore the biological mechanisms that influence hand grip strength variation, an epigenome-wide association study (EWAS) of hand grip strength in 672 middle-aged and elderly monozygotic twins (age 55–90 years) was performed, using both individual and twin pair level analyses, the latter controlling the influence of genetic variation. Moreover, as measurements of hand grip strength performed over 8 years were available in the elderly twins (age 73–90 at intake), a longitudinal EWAS was conducted for this subsample. No genome-wide significant CpG sites or pathways were found, however two of the suggestive top CpG sites were mapped to the COL6A1 and CACNA1B genes, known to be related to muscular dysfunction. By investigating genomic regions using the comb-p algorithm, several differentially methylated regions in regulatory domains were identified as significantly associated to hand grip strength, and pathway analyses of these regions revealed significant pathways related to the immune system, autoimmune disorders, including diabetes type 1 and viral myocarditis, as well as negative regulation of cell differentiation. The genes contributing to the immunological pathways were HLA-B, HLA-C, HLA-DMA, HLA-DPB1, MYH10, ERAP1 and IRF8, while the genes implicated in the negative regulation of cell differentiation were IRF8, CEBPD, ID2 and BRCA1. In conclusion, this exploratory study suggests hand grip strength to associate with differentially methylated regions enriched in immunological and cell differentiation pathways, and hence merits further investigations.

MicroRNA Expression Profiles Identify Biomarker for Differentiating the Embolic Stroke from Thrombotic Stroke

In order to identify potential biomarkers that distinguish the embolic stroke (ES) from thrombotic stroke (TS), a profile of microRNA expression was analyzed. The GSE60319 expression profile was downloaded from the Gene Expression Omnibus (GEO) database. The GEO2R was applied to screen for differentially expressed microRNAs (DEmiRNAs) between the embolic stroke group and thrombotic stroke group. The miRWalk was utilized to predict the target genes of DEmiRNAs. Genes associated with embolic stroke were downloaded from the Comparative Toxicogenomics Database. Cross reference of target genes to disease related genes was conducted to construct the DEmiRNA-gene network. The protein-protein interaction (PPI) network of overlapping genes was evaluated by STRING, using the MCODE and CytoHubba plugin of Cytoscape to identify the modules and hub genes. The enrichment of Kyoto Encyclopedia of Genes and Genomes (KEGG) in modules was performed. There were 30 microRNAs in total identified as DEmiRNAs between embolic stroke and thrombotic stroke groups, of which 8 were upregulated and 22 were downregulated. Among these differentially expressed miRNAs, miR-15a-5p, miR-17-5p, miR-19b-3p, and miR-20a-5p were significantly associated with an ES to TS. Using the miRWalk 3.0 online tool, target genes regulated by DEmiRNAs were predicted. In addition, disease related genes were predicted and compared with target genes of DEmiRNAs. 166 overlapped genes regulated by miR-15a-5p, miR-17-5p, miR-19b-3p, and miR-20a-5p were identified, suggesting their association with diseases that contributed to ES, mainly including atrial fibrillation, mitral valve stenosis, myocardial infarction, and aortic dissection. Therefore, miR-15a-5p, miR-17-5p, miR-19b-3p, and miR-20a-5p were promising candidate biomarkers for differentiating an ES from TS. The PPI network demonstrated that miR-15a-5p, miR-17-5p, miR-19b-3p, and miR-20a-5p were associated with an ES by mainly regulating “CCND1, E2F2, E2F3, ITCH, UBE4A, UBE3C, RBL2, FBXO31, EIF2C4, and EIF2C1”. Furthermore, miR-15a-5p and miR-17-5p may function through “cell cycle, prostate cancer, and small cell lung cancer” while miR-19b-3p and miR-20a-5p function through “insulin resistance, hepatitis B, and viral carcinogenesis” and “vasopressin-regulated water reabsorption”, respectively. However, these results were approached in the manner of bioinformatics analysis; therefore, further verification is required.