Paolo Spallarossa

Insulin-like growth factor-1 and angiographically documented coronary artery disease☆

In conclusion, we have reported an association between low IGF-I concentrations and CAD in relatively young men. This observation raises the possibility that IGF-I deficiency could be part of the polymetabolic syndrome. Whether a subnormal IGF-I production is due to growth hormone secretory abnormalities or to other metabolic reasons (e.g., insulin resistance or fat distribution, or both) is still unknown.

Doxorubicin induces senescence or apoptosis in rat neonatal cardiomyocytes by regulating the expression levels of the telomere binding factors 1 and 2

Low or high doses of doxorubicin induce either senescence or apoptosis, respectively, in cardiomyocytes. The mechanism by which different doses of doxorubicin may induce different stress-response cellular programs is not well understood. A recent study showed that the level of telomere dysfunction may induce senescence or apoptosis. We investigated the pathways to both apoptosis and senescence in neonatal rat cardiomyocytes and in H9c2 cells exposed to a single pulsed incubation with low or high doses of doxorubicin. High-dose doxorubicin strongly reduces TRF2 expression while enhancing TRF1 expression, and it determines early apoptosis. Low-dose doxorubicin induces downregulation of both TRF2 and TRF1, and it also increases the senescence-associated-beta-galactosidase activity, downregulates the checkpoint kinase Chk2, induces chromosomal abnormalities, and alters the cell cycle. The involvement of TRF1 and TRF2 with apoptosis and senescence was assessed by short interfering RNA interference. The cells maintain telomere dysfunction and a senescent phenotype over time and undergo late death. The increase in the phase>4N and the presence of micronuclei and anaphase bridges indicate that cells die by mitotic catastrophe. p38 modulates TRF2 expression, whereas JNK and cytoplasmic p53 regulate TRF1. Pretreatment with specific inhibitors of MAPKs and p53 may either attenuate the damage induced by doxorubicin or shift the cellular response to stress from senescence to apoptosis. In conclusion, various doses of doxorubicin induce differential regulation of TRF1 and TRF2 through p53 and MAPK, which is responsible for inducing either early apoptosis or senescence and late death due to mitotic catastrophe.

Adipose tissue immune response: novel triggers and consequences for chronic inflammatory conditions.

Adipose tissue inflammation mediates the association between excessive body fat accumulation and several chronic inflammatory diseases. A high prevalence of obesity-associated adipose tissue inflammation was observed not only in patients with cardiovascular conditions but also in patients with inflammatory bowel diseases, abdominal aortic aneurysm, or cardiorenal syndrome. In addition to excessive caloric intake, other triggers promote visceral adipose tissue inflammation followed by chronic, low-grade systemic inflammation. The infiltration and accumulation of immune cells in the inflamed and hypertrophied adipose tissue promote the production of inflammatory cytokines, contributing to target organ damages. This comorbidity seems to delimit subgroups of individuals with systemic adipose tissue inflammation and more severe chronic inflammatory diseases that are refractory to conventional treatment. This review highlights the association between adipose tissue immune response and the pathophysiology of visceral adiposity-related chronic inflammatory diseases, while suggesting several new therapeutic strategies.

Evaluation of growth hormone administration in patients with chronic heart failure secondary to coronary artery disease.

We have examined the effects of 6 months of treatment with growth hormone (GH) (0.02 U/kg/day) in 10 patients with chronic postischemic cardiac failure. Ten patients matched for age, body mass index, functional class, and ejection fraction served as a control group. In the GH group, 1 patient died and 2 were withdrawn from the study because of arrhythmia or worsening of heart failure. In the control group, 1 patient died and 1 patient was withdrawn from the study because of progressive heart failure. Among GH patients, those with an unfavorable outcome had a greater left ventricular end-diastolic diameter (79, 82, and 88 mm) on entry to the study than patients without adverse events (range 62 to 72 mm). At the end of the study, the seven GH patients reported a feeling of well-being and had a significant increase in their exercise test duration (462 +/- 121 vs 591 +/- 105 seconds, p <0.05). Low baseline insulin-like growth factor-I values were increased with GH treatment (189 +/- 52 vs 100 +/- 22 ng/ml, p <0.01). GH did not change left ventricular diameters or wall thickness. A trend toward decreased serum triglyceride levels and adipose body tissue associated with an increase in high-density lipoproteins was observed in the GH group. In conclusion, our present data support previous suggestions that GH treatment exerts some beneficial effects in patients with chronic, stabilized, moderately severe heart failure, but may have deleterious effects in patients with more severe heart failure.

CD14CD16 Monocyte Subset Levels in Heart Failure Patients

Our aim was to define the distribution of monocyte subsets in a cohort of congestive heart failure (CHF) patients, to verify whether increased severity of CHF is linked to the expansion of specific monocyte subsets, and finally to investigate the relationship between monocyte subset relative frequencies, laboratory parameters of inflammation, and monocyte ACE expression. Thirty consecutive CHF patients and 26 healthy control subjects were evaluated for peripheral blood monocyte expression of CD14, CD16 and CD143 (ACE) by flow-cytometry, and for endothelial-derived soluble CD146 levels by ELISA. CD14++CD16+ frequency was significantly higher in CHF patients than in Controls (%, median value and IQ) (12.3, 8.7–14.8 vs 5.9, 4.7–6.9, p++CD16+ levels. Frequencies of CD14+CD16+ monocytes were significantly lower in CHF patients as compared to Controls, and negatively correlated with levels of soluble CD146 (r = −0.529; p 0.048). In conclusion, monocytic CD14++CD16+ frequency and CD143 levels are increased and reflect disease status and progressive cardiac deterioration in CHF patients. The CD14+CD16+ subset is depleted in CHF and is linked to endothelial damage in this group of patients. Although the question of whether differences in monocyte CD14CD16 expansion are causal or whether they represent a marker of HF progression which is potentially relevant for risk prediction remains unanswered, we believe that our data represent an important tool for exploring the role of selective inflammatory pathways in CHF progression.

p38 MAPK and JNK Antagonistically Control Senescence and Cytoplasmic p16INK4A Expression in Doxorubicin-Treated Endothelial Progenitor Cells

Patients treated with low-dose anthracyclines often show late onset cardiotoxicity. Recent studies suggest that this form of cardiotoxicity is the result of a progenitor cell disease. In this study we demonstrate that Cord Blood Endothelial Progenitor Cells (EPCs) exposed to low, sub-apoptotic doses of doxorubicin show a senescence phenotype characterized by increased SA-b-gal activity, decreased TRF2 and chromosomal abnormalities, enlarged cell shape, and disarrangement of F-actin stress fibers accompanied by impaired migratory ability. P16 INK4A localizes in the cytoplasm of doxorubicin-induced senescent EPCs and not in the nucleus as is the case in EPCs rendered senescent by different stimuli. This localization together with the presence of an arrest in G2, and not at the G1 phase boundary, which is what usually occurs in response to the cell cycle regulatory activity of p16INK4A, suggests that doxorubicin-induced p16 INK4A does not regulate the cell cycle, even though its increase is closely associated with senescence. The effects of doxorubicin are the result of the activation of MAPKs p38 and JNK which act antagonistically. JNK attenuates the senescence, p16 INK4A expression and cytoskeleton remodeling that are induced by activated p38. We also found that conditioned medium from doxorubicin-induced senescent cardiomyocytes does not attract untreated EPCs, unlike conditioned medium from apoptotic cardiomyocytes which has a strong chemoattractant capacity. In conclusion, this study provides a better understanding of the senescence of doxorubicin-treated EPCs, which may be helpful in preventing and treating late onset cardiotoxicity.

Relationship between vitamin D status and left ventricular geometry in a healthy population: results from the Baltimore Longitudinal Study of Aging

The effects of vitamin D on the heart have been studied in patients with cardiac disease, but not in healthy persons. We investigated the relation between vitamin D status and left ventricular (LV) structure and function in community‐dwelling subjects without heart disease.

Therapeutic Use of Creatine in Brain or Heart Ischemia: Available Data and Future Perspectives

Creatine (Cr) is essential in safeguarding ATP levels and in moving ATP from its production site (mitochondria) to the cytoplasmic regions where it is used. Moreover, it has effects unrelated to energy metabolism, such as free radical scavenging, antiapoptotic action, and protection against excitotoxicity. Recent research has studied Cr‐derived compounds (Cr benzyl ester and phos‐pho–Cr–magnesium complex) that reproduce the neuroprotective effects of Cr while better crossing the neuronal plasma membrane and, hopefully, the blood–brain barrier (BBB). Intracellular levels of Cr can be increased by incubation with Cr or some of its derivatives, and this increase is protective against anoxic or ischemic damage. A large amount of experimental evidence shows that pretreatment with Cr is capable of reducing the damage induced by ischemia or anoxia in both heart and brain, and that such treatment may also be useful even after stroke or myocardial infarction (MI) has already occurred. Cr has been safely administered to patients affected by several neurological diseases, yet it has never been tested in human brain ischemia, the condition where its rationale is strongest. Phosphocreatine (PCr) has been administered after human MI, where it proved to be safe and probably helpful. Cr should be tested in the prophylactic protection against human brain ischemia and either Cr or PCr should be further tested in MI. Moreover, Cr‐ or PCr‐derived drugs should be developed in order to overcome these molecules’ limitations in crossing the BBB and the cell plasma membrane.

Relationship between inter-arm difference in systolic blood pressure and arterial stiffness in community-dwelling older adults.

A significant inter‐arm difference in systolic blood pressure (IADSBP) has recently been associated with worse cardiovascular outcomes. The authors hypothesized that part of this association is mediated by arterial stiffness, and examined the relationship between significant IADSBP and carotid‐femoral pulse wave velocity (CF‐PWV) in a sample from the Baltimore Longitudinal Study of Aging. Of 1045 participants, 50 (4.8%) had an IADSBP ≥10 mm Hg at baseline, and 629 had completed data from ≥2 visits (for a total of 1704 visits during 8 years). CF‐PWV was significantly higher in patients with an IADSBP ≥10 mm Hg (7.3±1.9 vs 8.2±2, P=.002). Compared with others, patients with IADSBP ≥10 mm Hg also had higher body mass index, waist circumference, and triglycerides; higher prevalence of diabetes; and lower high‐density lipoprotein (HDL) cholesterol (P<.001 for all). A significant association with IADSBP ≥10 mm Hg was observed for CF‐PWV in both cross‐sectional (odds ratio [OR], 1.19; 95% confidence interval [CI], 1.06–1.87; P=.01) and longitudinal (OR, 1.15; 95% CI, 1.03–1.29; P=.01) multivariate analyses. Female sex, Caucasian race, high body mass index (plus diabetes and low HDL cholesterol only cross‐sectionally) were other independent correlates of IADSBP ≥10 mm Hg. Significant IADSBP is associated with increased arterial stiffness in community‐dwelling older adults.

Improving the preclinical models for the study of chemotherapy-induced cardiotoxicity: a Position Paper of the Italian Working Group on Drug Cardiotoxicity and Cardioprotection

AbstractAlthough treatment for heart failure induced by cancer therapy has improved in recent years, the prevalence of cardiomyopathy due to antineoplastic therapy remains significant worldwide. In addition to traditional mediators of myocardial damage, such as reactive oxygen species, new pathways and target cells should be considered responsible for the impairment of cardiac function during anticancer treatment. Accordingly, there is a need to develop novel therapeutic strategies to protect the heart from pharmacologic injury, and improve clinical outcomes in cancer patients. The development of novel protective therapies requires testing putative therapeutic strategies in appropriate animal models of chemotherapy-induced cardiomyopathy. This Position Paper of the Working Group on Drug Cardiotoxicity and Cardioprotection of the Italian Society of Cardiology aims to: (1) define the distinctive etiopatogenetic features of cardiac toxicity induced by cancer therapy in humans, which include new aspects of mitochondrial function and oxidative stress, neuregulin-1 modulation through the ErbB receptor family, angiogenesis inhibition, and cardiac stem cell depletion and/or dysfunction; (2) review the new, more promising therapeutic strategies for cardioprotection, aimed to increase the survival of patients with severe antineoplastic-induced cardiotoxicity; (3) recommend the distinctive pathological features of cardiotoxicity induced by cancer therapy in humans that should be present in animal models used to identify or to test new cardioprotective therapies.