Subclinical atherosclerosis and accelerated epigenetic age mediated by inflammation: a multi-omics study

AIMS

Epigenetic age is emerging as a personalized and accurate predictor of biological age. The aim of this article is to assess the association of subclinical atherosclerosis with accelerated epigenetic age and to investigate the underlying mechanisms mediating this association.

METHODS AND RESULTS

Whole blood methylomics, transcriptomics, and plasma proteomics were obtained for 391 participants of the Progression of Early Subclinical Atherosclerosis study. Epigenetic age was calculated from methylomics data for each participant. Its divergence from chronological age is termed epigenetic age acceleration. Subclinical atherosclerosis burden was estimated by multi-territory 2D/3D vascular ultrasound and by coronary artery calcification. In healthy individuals, the presence, extension, and progression of subclinical atherosclerosis were associated with a significant acceleration of the Grim epigenetic age, a predictor of health and lifespan, regardless of traditional cardiovascular risk factors. Individuals with an accelerated Grim epigenetic age were characterized by an increased systemic inflammation and associated with a score of low-grade, chronic inflammation. Mediation analysis using transcriptomics and proteomics data revealed key pro-inflammatory pathways (IL6, Inflammasome, and IL10) and genes (IL1B, OSM, TLR5, and CD14) mediating the association between subclinical atherosclerosis and epigenetic age acceleration.

CONCLUSION

The presence, extension, and progression of subclinical atherosclerosis in middle-aged asymptomatic individuals are associated with an acceleration in the Grim epigenetic age. Mediation analysis using transcriptomics and proteomics data suggests a key role of systemic inflammation in this association, reinforcing the relevance of interventions on inflammation to prevent cardiovascular disease.

Silencing of microRNA-106b-5p prevents doxorubicin-mediated cardiotoxicity through modulation of the PR55α/YY1/sST2 signaling axis

Clinical use of doxorubicin (Dox), an anthracycline with potent anti-tumor effects, is limited because of its highly chemotherapy-induced cardiotoxicity (CIC). After myocardial infarction (MI), we have recently identified Yin Yang-1 (YY1) and histone deacetylase 4 (HDAC4) as two factors involved in the overexpression of the isoform soluble suppression of tumorigenicity 2 (sST2) protein, which acts as a decoy receptor blocking the favorable effects of IL-33. Therefore, high levels of sST2 are associated with increased fibrosis, remodeling, and worse cardiovascular outcomes. No data exist on the role of the YY1/HDAC4/sST2 axis in CIC. This study aimed to evaluate the pathophysiological implication of the molecular YY1/HDAC4/sST2 axis in remodeling that is developed in patients treated with Dox as well as to suggest a novel molecular therapy to prevent anthracycline-induced cardiotoxicity. Here, we have characterized a novel nexus between miR106b-5p (miR-106b) levels and the YY1/HDAC4 axis in relation to the cardiac expression of sST2 using two experimental models with Dox-induced cardiotoxicity. The addition of Dox (5 μM) to human induced pluripotent stem cell-derived cardiomyocytes induced cellular apoptotic death via upregulation of miR-106b-5p (miR-106b), which was confirmed by specific mimic sequences. A functional blockage of miR-106b using the locked nucleic acid antagomir inhibited Dox-induced cardiotoxicity.

Laser microdissection and microarray analysis of the hippocampus of Ras-GRF1 knockout mice reveals gene expression changes affecting signal transduction pathways related to memory and learning

We used manual macrodissection or laser capture microdissection (LCM) to isolate tissue sections of the hippocampus area of Ras-GRF1 wild type and knockout mice brains, and analyzed their transcriptional patterns using commercial oligonucleotide microarrays. Comparison between the transcriptomes of macrodissected and microdissected samples showed that the LCM samples allowed detection of significantly higher numbers of differentially expressed genes, with higher statistical rates of significance. These results validate LCM as a reliable technique for in vivo genomic studies in the brain hippocampus, where contamination by surrounding areas (not expressing Ras-GRF1) increases background noise and impairs identification of differentially expressed genes. Comparison between wild type and knockout LCM hippocampus samples revealed that Ras-GRF1 elimination caused significant gene expression changes, mostly affecting signal transduction and related neural processes. The list of 36 most differentially expressed genes included loci concerned mainly with Ras/G protein signaling and cytoskeletal organization (i.e. 14-3-3gamma/zeta, Kcnj6, Clasp2) or related, cross-talking pathways (i.e. jag2, decorin, strap). Consistent with the phenotypes shown by Ras-GRF1 knockout mice, many of these differentially expressed genes play functional roles in processes such as sensory development and function (i.e. Sptlc1, antiquitin, jag2) and/or neurological development/neurodegeneration processes affecting memory and learning. Indeed, potential links to neurodegenerative diseases such as Alzheimer disease (AD) or Creutzfeldt-Jacobs disease (CJD), have been reported for a number of differentially expressed genes identified in this study (Ptma, Aebp2, Clasp2, Hebp1, 14-3-3gamma/zeta, Csnk1delta, etc.). These data, together with the previously described role of IRS and insulin (known Ras-GRF1 activators) in AD, warrant further investigation of a potential functional link of Ras-GRF1 to neurodegenerative processes.

Transcervical chorionic villus sampling beyond 12 weeks of gestation

The aim of this study was to evaluate the feasibility of transcervical chorionic villus sampling (CVS) after 12 completed weeks of pregnancy. The transcervical route for CVS, using thin biopsy forceps, was accomplished in 335 procedures in the study group, between 12 + 1 and 15 + 0 weeks. Cases were subdivided into two subgroups, the late (13 + 0 to 15 + 0 weeks) and intermediate (12 + 1 and 12 + 6 weeks) subgroups, and the results were compared with a previous series of 1202 early (8 + 0-12 + 0 weeks) transcervical CVS. A successful diagnosis was made in 97.3% of the cases. No differences were found in diagnostic success between the study subgroups, in comparison to the early transcervical CVS series. However, success rates in the study group increased from 90% in the first 60 procedures to 98.9% in the remaining cases (p < 0.001). Amniocentesis was eventually performed in nine cases (2.7%). All cases were rescanned 2 weeks after the procedure, and fetal demise was detected in five cases (1.5%). The spontaneous fetal loss rate up to 28 weeks was 3.1% (2.7% for intermediate and 4.0% for late subgroups). No cases of transverse limb reduction defects were observed. The results of our study suggest that the transcervical route for CVS beyond the 12th week of pregnancy has a satisfactory diagnostic success rate, and an acceptable pregnancy loss rate.

Ultrasound diagnostic features of twin reversed arterial perfusion sequence

Two cases of twin reversed arterial perfusion (TRAP) sequence with relevant ultrasound features that would help an accurate diagnosis are described. Available management options are proposed and discussed.