Jonica Campolo

Background: Mitochondrial dysfunction is increasingly implicated in coronary artery disease (CAD), but the relationship between mitochondrial DNA copy number (mtDNA‐CN) and mitochondrial homeostasis across CAD presentations remains unclear. We investigated mtDNA‐CN together with the expression of key regulators of mitochondrial biogenesis (PGC‐1α and TFAM) and mitophagy (PINK1) in patients with stable angina (SA) and acute coronary syndrome (ACS). Methods: This observational study included 334 patients: 170 ACS, 117 SA and 47 individuals with non‐obstructive coronary arteries (NCA). Peripheral blood mtDNA‐CN and the expression of PGC‐1α, TFAM and PINK1 were quantified by real‐time PCR. Associations with clinical characteristics, inflammatory markers and left ventricular ejection fraction (LVEF) were evaluated. Results: ACS patients exhibited significantly lower mtDNA‐CN than SA and NCA groups ( p = 0.01 and p = 0.004, respectively). PINK1 expression was reduced in both ACS ( p = 0.005) and SA ( p = 0.01) compared with NCA. TFAM expression was increased in SA ( p = 0.009), while PGC‐1α expression was higher in ACS ( p = 0.02). MtDNA‐CN and mitochondrial biomarkers were inversely associated with inflammatory markers, whereas mtDNA‐CN and TFAM correlated positively with LVEF. Lower mtDNA‐CN was independently associated with ACS (OR = 0.98, p = 0.0004) and SA (OR = 0.99, p = 0.04), while higher PINK1 expression was associated with reduced odds of SA ( p = 0.03) and ACS ( p = 0.02). Conclusions: Mitochondrial markers are altered across CAD phenotypes. ACS is characterized by lower mtDNA‐CN and altered expression of mitochondrial homeostasis‐related genes, whereas SA shows a pattern consistent with a possible compensatory response. Combined assessment of mtDNA‐CN and mitochondrial homeostasis–related gene expression may provide a novel biomarker strategy for CAD risk stratification and targeted therapies. Trial Registration: VICTORIA study, ( ClinicalTrials.gov Identifier: NCT06313645)

The risk of cancer from medical exposure to ionizing radiation (IR) in pediatric patients—particularly those with congenital heart disease (CHD)—is a concern, given the need for repeated X-ray-guided cardiac catheterization (CC) procedures throughout their lives. To better understand the effects of low-dose IR, this study—part of the European HARMONIC project—investigated changes in blood miRNA expression following CC in CHD patients. Small RNA sequencing was performed on a discovery cohort of 10 CHD patients at three time points: before CC (T0), immediately after (T1), and one year later (T2). Differentially expressed miRNAs were validated in an independent group of 15 patients using qRT-PCR. KEGG pathway annotation analysis was carried out to determine the biological pathways involving target genes regulated by the dysregulated miRNAs. At the discovery stage, 74 miRNAs were significantly differentially expressed between the T1 and T0 groups, 69 between the T2 and T0 groups, and 41 between the T2 and T1 groups (q-value < 0.05 and |log2(fold change)|>1). Sixteen miRNAs (9 up-regulated and 7 down-regulated) were found dysregulated in both T1 and T2 compared to T0. Additionally, seven known miRNAs were uniquely dysregulated at T2. qRT-PCR analysis of six selected miRNAs partially validated the sequencing results, confirming consistent expression patterns for four miRNAs across cohorts. Pathway enrichment analysis indicated that predicted miRNA target genes were overrepresented in several pathways, including those annotated as cancer-related (enrichment p<0.0001). These findings suggest potential associations with radiation exposure, but their biological significance and health implications remain uncertain and require further investigation.

Obesity is a major global health challenge characterized by chronic low-grade inflammation, oxidative stress, and an increased risk of cardiometabolic disorders. Although sex-related differences in inflammatory and redox biomarkers have been reported in obese populations, the molecular mechanisms underlying this heterogeneity remain incompletely understood. In this study, we applied a proteomics-based approach to investigate urinary extracellular vesicles from 45 obese individuals (BMI 30–40 kg/m²; age 50–70 years) in order to identify molecular signatures associated with metabolic dysregulation. Shotgun proteomics analysis performed by nanoLC–MS/MS enabled the identification of 3822 proteins. Hierarchical clustering of proteomic profiles revealed two distinct molecular groups, predominantly enriched in males (Group I) and females (Group II). Label-free quantitative analysis identified 466 differentially abundant proteins between the two clusters. Functional enrichment analysis highlighted pathways associated with immune response, metabolic regulation, and redox homeostasis, including glycolysis/gluconeogenesis, lysosome activity, leukocyte transendothelial migration, and glutathione, cysteine and methionine metabolism. Notably, proteins related to ferroptosis were enriched, suggesting the involvement of iron-dependent oxidative cell death mechanisms in the metabolic imbalance observed in a subset of subjects. Furthermore, the non-enzymatic glycosylation of urinary proteins was significantly higher in Group I compared with Group II (p = 0.0002), indicating increased formation of advanced glycation products in individuals with a more pronounced pro-oxidant state. Preliminary follow-up data suggested a higher incidence of pathological events, including cardiovascular complications, among individuals belonging to Group I. Overall, these findings demonstrate that urinary proteomic profiling can identify distinct molecular phenotypes among obese individuals and highlight oxidative stress, ferroptosis, and protein glycation as potential determinants of metabolic vulnerability, supporting the use of non-invasive proteomic approaches for improved risk stratification in obesity.

Vascular aging is recognized as one of the hallmarks of atherosclerosis. Currently, a growing body of evidence suggests that there exists a mutual crosstalk between telomere dysfunction and mitochondrial dysmetabolism during the process of vascular senescence. This underscores the importance of comprehensively studying the molecular mediators involved in this complex and intricate connection. In pursuit of this goal, the “VICTORIA” protocol entails a prospective single-center cohort study aimed at recruiting patients undergoing coronary angiography at Niguarda Hospital in Italy. The primary objective is to explore potential associations between peripheral markers of cell aging (telomere length and mtDNA content), dysregulation of non-coding RNA [specifically lncRNA TERRA and mitochondrial microRNA (MitomiR)], and the varied presentations of ischemic heart disease (stable angina, unstable angina, NSTEMI, and STEMI). Furthermore, we aim to investigate whether these markers correlate with vulnerable plaque characteristics, as assessed by optical coherence tomography findings. Additionally, systemic levels of pro-inflammatory biomarkers and novel indicators of senescence will be assessed. Patients will be followed up at 1 year to monitor primary outcomes including mortality, myocardial infarction, stroke, unplanned revascularization, and rehospitalization. The anticipated findings of this study hold promise for advancing our understanding of the telomere-mitochondria crosstalk, potentially paving the way for novel treatment modalities and refined risk stratification approaches for acute coronary syndrome.

Background: The European-funded Health Effects of Cardiac Fluoroscopy and Modern Radiotherapy in Pediatrics (HARMONIC) project aims to improve knowledge on the effects of medical exposure to ionizing radiation (IR) received during childhood. One of its objectives is to build a consolidated European cohort of pediatric patients who have undergone cardiac catheterization (Cath) procedures, with the goal of enhancing the assessment of long-term radiation-associated cancer risk. The purpose of our study is to provide a detailed description of the Italian cohort contributing to the HARMONIC project, including an analysis of cumulative IR exposure, reduction trend over the years and an overview of the prospective collection of biological samples for research in this vulnerable population. Methods: In a single-center retrospective cohort study, a total of 584 patients (323 males) with a median age of 6 (2–13) years, referred at the Pediatric Cardiology in Niguarda Hospital from January 2015 to October 2023, were included. Biological specimens from a subset of 60 patients were prospectively collected for biobanking at baseline, immediately post-procedure and after 12 months. Results: Two hundred fifty-nine (44%) patients were under 1 year old at their first procedure. The median KAP/weight was 0.09 Gy·cm²/kg (IQR: 0.03–0.20), and the median fluoroscopy time was 8.10 min (IQR: 4.00–16.25). KAP/weight ratio showed a positive correlation with the fluoroscopy time (Spearman’s rho = 0.679, p < 0.001). Significant dose reduction was observed either after implementation of an upgraded technology system and a radiation training among staff. The Italian cohort includes 1858 different types of specimens for Harmonic biobank, including blood, plasma, serum, clot, cell pellet/lymphocytes, saliva. Conclusions: In the Italian Harmonic cohort, radiation dose in cardiac catheterization varies by age and procedure type. An institution’s radiological protection strategy has contributed to a reduction in radiation dose over time. Biological samples provide a valuable resource for future research, offering an opportunity to identify potential early biomarkers for health surveillance and personalized risk assessment.

Telomere shortening, chromosomal damage, and mitochondrial dysfunction are major initiators of cell aging and biomarkers of many diseases. However, the underlying correlations between nuclear and mitochondrial DNA alterations remain unclear. We investigated the relationship between telomere length (TL) and micronucleus (MN) and their association with mitochondrial DNA copy number (mtDNAcn) in peripheral blood mononuclear cells (PBMCs) in response to 100 μM and 200 μM of hydrogen peroxide (H₂O₂) at 44, 72, and 96 h. Significant TL shortening was observed after both doses of H₂O₂ and at all times (all p < 0.05). A concomitant increase in MN was found at 72 h (p < 0.01) and persisted at 96 h (p < 0.01). An increase in mtDNAcn (p = 0.04) at 200 µM of H₂O₂ was also found. In PBMCs treated with 200 µM H₂O₂, a significant inverse correlation was found between TL and MN (r = −0.76, p = 0.03), and mtDNA content was directly correlated with TL (r = 0.6, p = 0.04) and inversely related to MN (r = −0.78, p = 0.02). Telomere shortening is the main triggering mechanism of chromosomal damage in stimulated T lymphocytes under oxidative stress. The significant correlations between nuclear DNA damage and mtDNAcn support the notion of a telomere–mitochondria axis that might influence age-associated pathologies and be a target for the development of relevant anti-aging drugs.

Cardiogenic shock (CS) portends a dismal prognosis if hypoperfusion triggers uncontrolled inflammatory and metabolic derangements. We sought to investigate metabolomic profiles and temporal changes in IL6, Ang-2, and markers of glycocalyx perturbation from admission to discharge in eighteen patients with heart failure complicated by CS (HF-CS). Biological samples were collected from 18 consecutive HF-CS patients at admission (T0), 48 h after admission (T1), and at discharge (T2). ELISA analytical techniques and targeted metabolomics were performed Seven patients (44%) died at in-hospital follow-up. Among the survivors, IL-6 and kynurenine were significantly reduced at discharge compared to baseline. Conversely, the amino acids arginine, threonine, glycine, lysine, and asparagine; the biogenic amine putrescine; multiple sphingolipids; and glycerophospholipids were significantly increased. Patients with HF-CS have a metabolomic fingerprint that might allow for tailored treatment strategies for the patients’ recovery or stabilization.

Telomere dysfunction is implicated in vascular aging and shorter leucocyte telomeres are associated with an increased risk of atherosclerosis, myocardial infarction, and heart failure. Another pathophysiological mechanism that explains the causal relationship between telomere shortening and atherosclerosis development focuses on the clonal hematopoiesis of indeterminate potential (CHIP), which represents a new and independent risk factor in atherosclerotic cardiovascular diseases. Since telomere attrition has a central role in driving vascular senescence, understanding telomere biology is essential to modulate the deleterious consequences of vascular aging and its cardiovascular disease-related manifestations. Emerging evidence indicates that a class of long noncoding RNAs transcribed at telomeres, known as TERRA for “TElomeric Repeat-containing RNA”, actively participates in the mechanisms regulating telomere maintenance and chromosome end protection. However, the multiple biological functions of TERRA remain to be largely elucidated. In particular, the role of TERRA in vascular biology is surprisingly unknown. In this review, we discuss the current knowledge of TERRA and its roles in telomere biology. Additionally, we outline the pieces of evidence that exist regarding the relationship between TERRA dysregulation and disease. Finally, we speculate on how a comprehensive understanding of TERRA transcription in the cardiovascular system may provide valuable insights into telomere-associated vascular aging, offering great potential for new therapeutic approaches.

Background: Both telomere shortening and the chromosome 9p21.3 (Chr9p21) rs1333049 (G/C) variant are involved in coronary artery disease (CAD) risk, likely affecting mechanisms related to cell cycle arrest and vascular senescence. The aim of the study was to examine the link between Chr9p21 rs1333049 variant and leucocyte telomere length (LTL), as well as their interactive effect on the risk of major adverse cardiovascular events (MACEs). Methods: A cohort of 472 patients with angiographically proven and clinically stable CAD were included in the study. At baseline, the LTL, biochemical parameters, and genotype analysis of Chr9p21 rs1333049 variant were measured in all patients. The primary endpoint of this study was the occurrence of MACE defined as a composite of coronary-related death, nonfatal MI, and coronary revascularization. Results: On multivariable linear regression analysis, age (p = 0.02) and Chr9p21 rs1333049 variant (p = 0.002) were the only independent predictors of LTL levels. Carriers of the CC genotype of this SNP had shorter telomeres than GC carriers (p = 0.02) and GG carriers (p = 0.0005). After a follow-up with a mean period of 62 ± 19 months, 90 patients (19.1%) had MACE. Short LTL was an independent prognostic factor of MACE incidence (HR:2.2; 95% CI: 1.3–3.7; p = 0.005) after adjustment for potential confounders. There was a significant interaction (p = 0.01) between the LTL and rs1333049 variant, with patients with risk-allele C and short LTL having a higher risk (HR:5.8; 95% CI: 1.8–19.2; p = 0.004). Conclusion: A strong relationship between LTL and Chr9p21 rs1333049 variant was identified, and they interactively affect the risk of poor prognosis in CAD patients.