Adiposity assessed by anthropometric measures has a similar or greater predictive ability than dual-energy X-ray absorptiometry measures for abdominal aortic calcification in community-dwelling older adults

A combined circulating microRNA panel predicts the risk of vascular calcification in community-dwelling older adults with age strata differences

BACKGROUND

Older adults have a higher risk of developing vascular calcification (VC). Circulating miRNAs can be potential risk indicators. However, prior studies used single miRNA mostly, whereas miRNA panels were rarely evaluated. We aimed to examine whether a miRNA panel outperformed each miRNA alone, and analyzed whether advanced age affected VC risk predictive performance offered by the miRNA panel.

METHODS

We prospectively enrolled older adults (age ≥65 years) during their annual health checkup in 2017, and examined their VC severity followed by analyzing sera for VC regulatory miRNAs (miR-125b-5p, miR-125b-3p, and miR-378a-3p). We used multiple regression analyses to determine associations between each miRNA or a 3-combind panel and VC risk, followed by area under the receiver-operating-characteristics curve (AUROC) analysis. Participants were further divided to those of 65-75 and ≥75 years for comparison.

RESULTS

From 199 older adults screened, 169 (median age, 73.3 years) with available calcification assessment were analyzed, among whom 74.6 % having VC. Those with VC had significantly lower circulating miR-125b-5p, miR-125b-3p, and miR-378a-3p levels than those without. Regression analyses showed that the 3-combined miRNA panel exhibited significant associations with VC risk, with significantly higher AUROC than those of models based on individual miRNA. Importantly, in those ≥75 years, the miRNA-predicted risk of VC was more prominent than that in the 65-75 years group.

CONCLUSION

A miRNA panel for VC risk prediction might outperform individual miRNA alone in older adults, and advanced age modified the association between circulating miRNAs and the risk of VC.

Comparative analysis of calcified soft tissues revealed shared deregulated pathways

Introduction

Calcification of soft tissues is a common age-related pathology that primarily occurs within vascular tissue. The mechanisms underlying pathological calcification in humans and tissue specificity of the process is still poorly understood. Previous studies examined calcified tissues on one to one basis, thus preventing comparison of deregulated pathways across tissues.

Purpose

This study aimed to establish common and tissue-specific changes associated with calcification in aorta, artery tibial, coronary artery and pituitary gland in subjects from the Genotype-Tissue Expression (GTEx) dataset using its RNA sequencing and histological data.

Methods

We used publicly available data from the GTEx database https://gtexportal.org/home/aboutGTEx. All GTEx tissue samples were derived by the GTEx consorcium from deceased donors, with age from 20 to 79, both men and women. GTEx study authorization was obtained via next-of-kin consent for the collection and banking of de-identified tissue samples for scientific research. Hematoxylin and eosin (H&E) staining of arteries were manually graded based on the presence of calcification on a scale from zero to four, where zero designates absence of calcification and four designates severe calcification. Samples with fat contamination and mislabeled tissues were excluded, which left 430 aorta, 595 artery tibial, 124 coronary artery, and 283 pituitary samples for downstream gene expression analysis. Transcript levels of protein-coding genes were associated with calcification grade using sex, age bracket and cause of death as covariates, and tested for pathway enrichment using gene set enrichment analysis.

Results

We identified calcification deposits in 28 (6.5%) aortas, 121 (20%), artery tibials, 54 (43%), coronary arteries, and 24 (8%) pituitary glands of GTEx subjects. We observed an age-dependent increase in incidence of calcification in all vascular tissues, but not in pituitary. Subjects with calcification in the artery tibial were significantly more likely to have calcification in the coronary artery (OR = 2.56, p = 6.3e-07). Markers of calcification previously established in preclinical and in vitro studies, e.g., BMP2 and RUNX2, were deregulated in the calcified tibial and coronary arteries, confirming the relevance of these genes to human pathology. Differentially expressed genes associated with calcification poorly overlapped across tissues suggesting tissue-specific nuances in mechanisms of calcification. Nevertheless, calcified arteries unanimously down-regulated pathways of intracellular transport and up-regulated inflammatory pathways suggesting these as universal targets for pathological calcification. In particular, PD-1 and PD-L1 genes were up-regulated in calcified tissues but not in the blood of the same subjects, suggesting that localized inflammation contributes to pathological calcification.

Conclusion

Pathological calcification is a prevalent disease of aging that shares little changes in expression in individual genes across tissues. However, our analysis suggests that it potentially can be targeted by alleviating local inflammation of soft tissues.

The context-dependent role of transforming growth factor-β/miR-378a-3p/connective tissue growth factor in vascular calcification: a translational study

BACKGROUND

Vascular calcification (VC) constitutes an important vascular pathology with prognostic importance. The pathogenic role of transforming growth factor-β (TGF-β) in VC remains unclear, with heterogeneous findings that we aimed to evaluate using experimental models and clinical specimens.

METHODS

Two approaches, exogenous administration and endogenous expression upon osteogenic media (OM) exposure, were adopted. Aortic smooth muscle cells (ASMCs) were subjected to TGF-β1 alone, OM alone, or both, with calcification severity determined. We evaluated miR-378a-3p and TGF-β1 effectors (connective tissue growth factor; CTGF) at different periods of calcification. Results were validated in an ex vivo model and further in sera from older adults without or with severe aortic arch calcification.

RESULTS

TGF-β1 treatment induced a significant dose-responsive increase in ASMC calcification without or with OM at the mature but not early or mid-term VC period. On the other hand, OM alone induced VC accompanied by suppressed TGF-β1 expressions over time; this phenomenon paralleled the declining miR-378a-3p and CTGF expressions since early VC. TGF-β1 treatment led to an upregulation of CTGF since early VC but not miR-378a-3p until mid-term VC, while miR-378a-3p overexpression suppressed CTGF expressions without altering TGF-β1 levels. The OM-induced down-regulation of TGF-β1 and CTGF was also observed in the ex vivo models, with compatible results identified from human sera.

CONCLUSIONS

We showed that TGF-β1 played a context-dependent role in VC, involving a time-dependent self-regulatory loop of TGF-β1/miR-378a-3p/CTGF signaling. Our findings may assist subsequent studies in devising potential therapeutics against VC.

Abdominal aortic calcification is associated with Fib-4 index and low body mass index in type 2 diabetes: a retrospective cross-sectional study

AIMS

This study aimed to clarify the nature of the relationship between the abdominal aortic calcification (AAC) grade and the presence of cardiovascular diseases and determine factors related to AAC grade in participants with type 2 diabetes (T2DM).

METHODS

This retrospective cross-sectional study enrolled 264 in participants with T2DM. The AAC score and length were measured using the lateral abdominal radiographs. Logistic regression models were used to assess the associations between AAC scores/lengths and the presence of coronary artery disease (CAD), cerebral infarction (CI), and peripheral artery disease (PAD). The correlation between AAC scores/lengths and other clinical factors were evaluated using linear regression models.

RESULTS

The AAC score was significantly correlated with prevalent CAD and CI independent of age and smoking but not with the prevalence of PAD. AAC length was not significantly correlated with the presence of CAD, CI, or PAD; however, the sample size was insufficient to conclude probably due to low prevalence. Both the AAC score and length were correlated inversely with body mass index (BMI) and, with the Fib-4 index >2.67; these correlations were significant after adjusting for cardiovascular risk factors and BMI, although AAC was not associated with ultrasonography-diagnosed fatty liver. There was a significant interaction between BMI and Fib-4 index; lower BMI and Fib-4 index >2.67 demonstrated a synergistic association with high AAC grade.

CONCLUSIONS

AAC score is associated with CAD and CI morbidity in participants with T2DM. Low BMI and Fib-4 index >2.67 can be valuable indicators of AAC in people with T2DM.

Impact of Adiposity and Fat Distribution, Rather Than Obesity, on Antibodies as an Illustration of Weight-Loss-Independent Exercise Benefits

Obesity represents a risk factor for a variety of diseases because of its inflammatory component, among other biological patterns. Recently, with the ongoing COVID-19 crisis, a special focus has been put on obesity as a status in which antibody production, among other immune functions, is impaired, which would impact both disease pathogenesis and vaccine efficacy. Within this piece of writing, we illustrate that such patterns would be due to the increased adiposity and fat distribution pattern rather than obesity (as defined by the body mass index) itself. Within this context, we also highlight the importance of the weight-loss-independent effects of exercise.

Vascular Calcification as an Underrecognized Risk Factor for Frailty in 1783 Community-Dwelling Elderly Individuals

Background Vascular calcification (VC) is associated with high morbidity and mortality among older adults, a population that exhibits a higher tendency for developing frailty at the same time. Whether VC serves as a risk factor for the development of frailty in this population remains unclear. Methods and Results We analyzed a prospectively assembled cohort of community-dwelling older adults between 2014 and 2017 (n=1783). Frailty and prefrailty were determined on the basis of the Study of Osteoporotic Fractures criteria, and VC was measured using semiquantitative aortic arch calcification (AAC) and abdominal aortic calcification scoring. We conducted multiple logistic regression with prefrailty or frailty as the dependent variable, incorporating sociodemographic profiles, comorbidities, medications, laboratory data, AAC status/severity, and other geriatric phenotypes. Among all participants, 327 (18.3%) exhibited either prefrailty (15.3%) or frailty (3.1%), and 648 (36.3%) exhibited AAC. After adjusting for multiple confounders, we found that AAC incidence was associated with a substantially higher probability of prefrailty or frailty (odds ratio [OR], 11.9; 95% CI, 7.9-15.4), with a dose-responsive relationship (OR for older adults with AAC categories 1, 2, and 3 was 9.3, 13.6, and 52.5, respectively). Similar association was observed for older adults with abdominal aortic calcification (OR, 5.0; 95% CI, 1.3-19.5), and might be replicable in another cohort of patients with end-stage renal disease. Conclusions Severity of VC exhibited a linear positive relationship with frailty in older adults. Our findings suggest that a prompt diagnosis and potential management of VC may assist in risk mitigation for patients with frailty.

Adiposity Indicators as Cardio-Metabolic Risk Predictors in Adults from Country with High Burden of Obesity

BACKGROUND

In Qatar more than 70% 0f the adults are overweight and obese. Different adiposity assessment methods have been proposed to identify individuals at cardio-metabolic risk.

PURPOSE

This study aimed to compare anthropometric indicators with Dual-energy X-ray absorptiometry (DXA) -derived adiposity indicators in predicting cardio-metabolic risk among Qatari adults.

PATIENTS AND METHODS

A random sample of five hundred and fifty-eight (558) healthy Qatari adults (men and women) aged 20 to 50 years was obtained from Qatar Biobank survey data. Anthropometric data (weight, height, and waist circumference), the DXA-derived data, and cardio-metabolic (CM) risk parameters were analyzed. A Spearman partial correlation coefficient, Receiver Operating Characteristics (ROC) curve and an area under curve (AUC) were used to assess the predicting ability of adiposity indicators for CM risk factors.

RESULTS

Adiposity indices (anthropometric and DXA) were significantly correlated with most of the CM indicators (r= -0.292 to 0.486, p< 0.001). The AUC of waist to height ratio (WHtR) was significantly higher than that of body mass index (BMI) and waist circumference (WC) in the prediction of low high density lipoprotein (HDL) (AUC=0.65, AUC=0.59; AUC=0.64), high low density lipoprotein (LDL) (AUC=0.67; AUC=0.62; AUC=0.66), high cholesterol (AUC=0.66; AUC=0.63; AUC=0.63), and high Homeostatic Model Assessment- (HOMA) (AUC= 0.81; AUC= 0.78; AUC=0.78). Among DXA- parameters, trunk fat had the highest AUCs for total cholesterol (AUC= 0.64, CI=0.56, 0.73), triglycerides and glucose index (TyG) (AUC=0.69, CI=0.64, 0.74), and HOMA (AUC=0.78, CI= 0.73, 0.84).

CONCLUSION

Results of the present study show that adiposity indicators (WC and WHtR) are clinically valuable tools to identify individuals at risk of CVD compared to DXA-derived parameters, while DXA can provide more accurate estimates.

Diabetes and Abdominal Aortic Calcification-a Systematic Review

PURPOSE OF REVIEW

A systematic literature review was performed to evaluate diabetes mellitus (DM) as a risk factor of abdominal aortic calcification (AAC), and address factors that might contribute to the development of AAC in DM patients.

RECENT FINDINGS

DM is an independent risk factor of AAC development. Bone metabolism along with lifestyle factors among DM patients makes them more prone to AAC. Hip and vertebral fractures, high phosphate, smoking, hypertension, and low osteocalcin could make DM patients prone to AAC. Low levels of high-density lipoprotein (HDL), high low-density lipoprotein (LDL), high total cholesterol/HDL ratio, low bone mineral density (BMD) may be risk factors, but the literature is more ambiguous. Body mass index (BMI) does not appear to increase risk of AAC. High phosphate levels and low osteocalcin levels seem to be biomarkers of AAC in patients with diabetes. However, the association between DM and AAC is complicated.