Circulating miR-122-5p, miR-92a-3p, and miR-18a-5p as Potential Biomarkers in Human Liver Transplantation Follow-Up.

The requirement of blood-circulating sensitive biomarkers for monitoring liver transplant (LT) is currently a necessary step aiming at the reduction of standard invasive protocols, such as liver biopsy. In this respect, the main objective of this study is to assess circulating microRNA (c-miR) changes in recipients' blood before and after LT and to correlate their blood levels with gold standard biomarkers and with outcomes such as rejection or complications after graft. An miR profile was initially performed; then, the most deregulated miRs were validated by RT-qPCR in 14 recipients pre- and post-LT and compared to a control group of 24 nontransplanted healthy subjects. MiR-122-5p, miR-92a-3p, miR-18a-5p, and miR-30c-5p, identified in the validation phase, were also analyzed considering an additional 19 serum samples collected from LT recipients and focusing on different follow-up (FU) times. The results showed significant, FU-related changes in c-miRs. In particular, miR-122-5p, miR-92a-3p, and miR-18a-5p revealed the same trend after transplantation and an increase in their level was found in patients with complications, independently from FU times. Conversely, the variations in the standard haemato-biochemical parameters for liver function assessment were not significant in the same FU period, confirming the importance of c-miRs as potential noninvasive biomarkers for monitoring patients' outcomes.

Blood circulating miR-28-5p and let-7d-5p associate with premature ageing in Down syndrome.

Persons with Down syndrome (DS) undergo a premature ageing with early onset of age-related diseases. The main endpoint of this study was the identification of blood circulating microRNAs (c-miRs) signatures characterizing DS ageing process. A discovery phase based on array was performed in plasma samples obtained from 3 young (31 ± 2 years-old) and 3 elderly DS persons (66 ± 2 years-old). Then, a validation phase was carried out for relevant miRs by RT-qPCR in an enlarged cohort of 43 DS individuals (from 19 up to 68 years-old). A group of 30 non-trisomic subjects, as representative of physiological ageing, was compared. In particular miR-628-5p, miR-152-3p, miR-28-5p, and let-7d-5p showed a lower level in younger DS persons (age ≤ 50 years) respect to the age-matched controls. Among those, miR-28-5p and let-7d-5p were found significantly decreased in physiological ageing ( oldest group ), thus they emerged as possible biomarkers of premature ageing in DS. Moreover, measuring blood levels of beta amyloid peptides, Aß-42 was assessed at the lowest levels in physiological ageing and correlated with miR-28-5p and let-7d-5p in DS, while Aß-40 correlated with miR-628-5p in the same cohort. New perspectives in terms of biomarkers are discussed.

Adventitial Microcirculation Is a Major Target of SARS-CoV-2-Mediated Vascular Inflammation.

We report the case of a 77-year-old woman affected by coronavirus disease-19 (COVID-19) who developed an occlusive arterial disease of the lower limb requiring a left leg amputation. We studied the mechanisms of vascular damage by SARS-CoV-2 by means of a comprehensive multi-technique in situ analysis on the diseased popliteal arterial district, including immunohistochemistry (IHC), transmission electron microscopy (TEM) and miRNA analysis. At histological analyses, we observed a lymphocytic inflammatory infiltrate, oedema and endothelialitis of adventitial vasa vasorum while the media was normal and the intima had only minor changes. The vasa vasorum expressed the ACE2 receptor and factor VIII; compared with the controls, VEGFR2 staining was reduced. TEM analyses showed endothelial injury and numerous Weibel-Palade bodies in the cytoplasm. No coronavirus particle was seen. IL-6 protein and mRNA, together with miR-155-5p and miRs-27a-5p, which can target IL-6, were significantly increased compared with that in the controls. Our case report suggests an involvement of adventitial artery microcirculation by inflammation in the course of COVID-19. Without evident signs of current infection by SARS-CoV-2, endothelial cells show a spectrum of structural and functional alterations that can fuel the cardiovascular complications observed in people infected with SARS-CoV-2.

MicroRNA profiles of human peripheral arteries and abdominal aorta in normal conditions: MicroRNAs-27a-5p, -139-5p and -155-5p emerge and in atheroma too.

Atherosclerosis may starts early in life and each artery has peculiar characteristics likely affecting atherogenesis. The primary objective of the work was to underpin the microRNA (miR)-profiling differences in human normal femoral, abdominal aortic, and carotid arteries. The secondary aim was to investigate if those identified miRs, differently expressed in normal conditions, may also have a role in atherosclerotic arteries at adult ages. MiR-profiles were performed on normal tissues, revealing that aorta and carotid arteries are more similar than femoral arteries. MiRs emerging from profiling comparisons, i.e., miR-155-5p, -27a-5p, and -139-5p, were subjected to validation by RT-qPCR in normal arteries and also in pathological/atheroma counterparts, considering all the available 20 artery specimens. The three miRs were confirmed to be differentially expressed in normal femoral vs aorta/carotid arteries. Differential expression of those miRs was also observed in atherosclerotic arteries, together with some miR-target proteins, such as vimentin, CD44, E-cadherin and an additional marker SLUG. The different expression of miRs and targets/markers suggests that aorta/carotid and femoral arteries differently activate molecular drivers of pathological condition, thus conditioning the morphology of atheroma in adult life and likely suggesting the future use of artery-specific treatment to counteract atherosclerosis.

Circulating miR-19a-3p and miR-19b-3p characterize the human aging process and their isomiRs associate with healthy status at extreme ages.

Blood circulating microRNAs (c-miRs) are potential biomarkers to trace aging and longevity trajectories to identify molecular targets for anti-aging therapies. Based on a cross-sectional study, a discovery phase was performed on 12 donors divided into four groups: young, old, healthy, and unhealthy centenarians. The identification of healthy and unhealthy phenotype was based on cognitive performance and capabilities to perform daily activities. Small RNA sequencing identified 79 differentially expressed c-miRs when comparing young, old, healthy centenarians, and unhealthy centenarians. Two miRs, that is, miR-19a-3p and miR-19b-3p, were found increased at old age but decreased at extreme age, as confirmed by RT-qPCR in 49 donors of validation phase. The significant decrease of those miR levels in healthy compared to unhealthy centenarians appears to be due to the presence of isomiRs, not detectable with RT-qPCR, but only with a high-resolution technique such as deep sequencing. Bioinformatically, three main common targets of miR-19a/b-3p were identified, that is, SMAD4, PTEN, and BCL2L11, converging into the FoxO signaling pathway, known to have a significant role in aging mechanisms. For the first time, this study shows the age-related increase of plasma miR-19a/b-3p in old subjects but a decrease in centenarians. This decrease is more pronounced in healthy centenarians and was confirmed by the modified pattern of isomiRs comparing healthy and unhealthy centenarians. Thus, our study paves the way for functional studies using c-miRs and isomiRs as additional parameter to track the onset of aging and age-related diseases using new potential biomarkers.

Circulating perilipin 2 levels are associated with fat mass, inflammatory and metabolic markers and are higher in women than men.

Perilipin 2 (PLIN2) is a protein involved in lipid storage and metabolism in non-adipose tissues. Detectable levels of circulating PLIN2 (cPLIN2) have been reported to be associated with some types of cancer, but no systematic analysis of age-related modifications in cPLIN2 levels has ever been performed. We measured serum cPLIN2 in a group of old people including centenarians in comparison with young subjects and tested possible correlations with parameters of body composition, fat and glucose metabolism, and inflammation. We found that: i. levels of cPLIN2 do not change with age, but women have higher levels of cPLIN2 with respect to men; ii. cPLIN2 levels strongly correlate to BMI, as well as fat and lean mass; iii. cPLIN2 levels strongly correlate with the proinflammatory adipokine leptin. Due to the adipogenic activity of leptin, it is hypothesized that cPLIN2 is affected and possibly regulated by this pleiotropic adipokine. Moreover, these results suggest that cPLIN2 (possibly together with leptin) could be assumed as a proxy for body adiposity.

Distinct profile of CD34+ cells and plasma-derived extracellular vesicles from triple-negative patients with Myelofibrosis reveals potential markers of aggressive disease.

BACKGROUND: Myelofibrosis (MF) is a clonal disorder of hemopoietic stem/progenitor cells (HSPCs) with high prevalence in elderly patients and mutations in three driver genes (JAK2, MPL, or CALR). Around 10-15% of patients are triple-negative (TN) for the three driver mutations and display significantly worse survival. Circulating extracellular vesicles (EVs) play a role in intercellular signaling and are increased in inflammation and cancer. To identify a biomolecular signature of TN patients, we comparatively evaluated the circulating HSPCs and their functional interplay with the microenvironment focusing on EV analysis. METHODS: Peripheral blood was collected from MF patients (n = 29; JAK2V617F mutation, n = 23; TN, n = 6) and healthy donors (HD, n = 10). Immunomagnetically isolated CD34+ cells were characterized by gene expression profiling analysis (GEP), survival, migration, and clonogenic ability. EVs were purified from platelet-poor plasma by ultracentrifugation, quantified using the Nanosight technology and phenotypically characterized by flow cytometry together with microRNA expression. Migration and survival of CD34+ cells from patients were also analyzed after in vitro treatments with selected inflammatory factors, i.e. (Interleukin (IL)-1ß, Tumor Necrosis Factor (TNF)-α, IL6) or after co-culture with EVs from MF patients/HD. RESULTS: The absolute numbers of circulating CD34+ cells were massively increased in TN patients. We found that TN CD34+ cells show in vitro defective functions and are unresponsive to the inflammatory microenvironment. Of note, the plasma levels of crucial inflammatory cytokines are mostly within the normal range in TN patients. Compared to JAK2V617F-mutated patients, the GEP of TN CD34+ cells revealed distinct signatures in key pathways such as survival, cell adhesion, and inflammation. Importantly, we observed the presence of mitochondrial components within plasma EVs and a distinct phenotype in TN-derived EVs compared to the JAK2V617F-mutated MF patients and HD counterparts. Notably, TN EVs promoted the survival of TN CD34+ cells. Along with a specific microRNA signature, the circulating EVs from TN patients are enriched with miR-361-5p. CONCLUSIONS: Distinct EV-driven signals from the microenvironment are capable to promote the TN malignant hemopoiesis and their further investigation paves the way toward novel therapeutic approaches for rare MF.

The carotid plaque as paradigmatic case of site-specific acceleration of aging process: The microRNAs and the inflammaging contribution.

Atherosclerosis is considered a chronic inflammatory disease of arteries associated with the aging process. Many risk factors have been identified and they are mainly related to life-styles, gene-environment interactions and socioeconomic status. Carotid and coronary artery diseases are the two major atherosclerotic conditions, being the primary cause of stroke and heart attack, respectively. Nevertheless, carotid plaque assumes particular aspects not only for the specific molecular mechanisms, but also for the types of atheroma which may be associated with a better or a worst prognosis. The identification of circulating blood biomarkers able to distinguish carotid plaque types (stable or vulnerable) is a crucial step for the improvement of adequate therapeutic approaches avoiding or delaying endarterectomy in the oldest old individuals (> 80 years), a population predicted to growth in the next years. The review highlights the most recent knowledge on carotid plaque molecular mechanisms, focusing on microRNAs (miRs), as a site-specific accelerated aging within the conceptual framework of Geroscience for new affordable therapies.

The peculiar aging of human liver: A geroscience perspective within transplant context.

An appraisal of recent data highlighting aspects inspired by the new Geroscience perspective are here discussed. The main findings are summarized as follows: i) liver has to be considered an immunological organ, and new studies suggest a role for the recently described cells named telocytes; ii) the liver-gut axis represents a crucial connection with environment and life style habits and may influence liver diseases onset; iii) the physiological aging of liver shows relatively modest alterations. Nevertheless, several molecular changes appear to be relevant: a) an increase of microRNA-31-5p; -141-3p; -200c-3p expressions after 60 years of age; b) a remodeling of genome-wide DNA methylation profile evident until 60 years of age and then plateauing; c) changes in transcriptome including the metabolic zones of hepatocyte lobules; d) liver undergoes an accelerated aging in presence of chronic inflammation/liver diseases in a sort of continuum, largely as a consequence of unhealthy life styles and exposure to environmental noxious agents. We argue that chronic liver inflammation has all the major characteristics of "inflammaging" and likely sustains the onset and progression of liver diseases. Finally, we propose to use a combination of parameters, mostly obtained by omics such as transcriptomics and epigenomics, to evaluate in deep both the biological age of liver (in comparison with the chronological age) and the effects of donor-recipient age-mismatches in the context of liver transplant.