Upregulation of TH/IL-17 Pathway-Related Genes in Human Coronary Endothelial Cells Stimulated with Serum of Patients with Acute Coronary Syndromes.

BACKGROUND: Inflammation plays an essential role in the development and complications of atherosclerosis plaques, including acute coronary syndromes (ACS). Indeed, previous reports have shown that within the coronary circulation of ACS patients, several soluble mediators are released. Moreover, it has been demonstrated that endothelial dysfunction might play an important role in atherosclerosis as well as ACS pathophysiology. However, the mechanisms by which these soluble mediators might affect endothelial functions are still largely unknown. We have evaluated whether soluble mediators contained in serum from coronary circulation of ACS patients might promote changes of gene profile in human coronary endothelial cells (HCAECs). METHODS: HCAECs were stimulated in vitro for 12 h with serum obtained from the coronary sinus (CS) and the aorta (Ao) of ACS patients; stable angina (SA) patients served as controls. Gene expression profiles of stimulated cells were evaluated by microarray and real-time PCR. RESULTS: HCAECs stimulated with serum from CS of ACS patients showed a significant change (upregulation and downregulation) in gene expression profile as compared with cells stimulated with serum from CS of SA patients. Moreover, ad hoc sub analysis indicated the upregulation of Th-17/IL-17 pathway-related genes. CONCLUSION: This study demonstrates that, in ACS patients, the chemical mediators released in the coronary circulation might be able to perturb coronary endothelial cells (ECs) modifying their gene profile. These modified ECs, through downregulation of protective gene and, mainly, through upregulation of gene able to modulate the Th-17/IL-17 pathway, might play a key role in progression of coronary atherosclerosis and in developing future acute events.

Long-term administration of ranolazine attenuates diastolic dysfunction and adverse myocardial remodeling in a model of heart failure with preserved ejection fraction.

BACKGROUND: To investigate the effects of chronic administration of ranolazine (RAN) on experimental model of heart failure with preserved ejection fraction. METHODS: Seven-weeks old Dahl salt-sensitive rats were fed a high salt diet for 5weeks to induce hypertension. Afterwards, rats continued with a high salt diet and were administered either with vehicle or RAN (20mg/kg/die, ip) for the following 8weeks. Control rats were maintained on a low salt diet. RESULTS: While systolic parameters were not altered, diastolic parameters were changed in high salt animals. Hemodynamic analysis showed a decreased dP/dt min, increased LVEDP, longer time constant and steeper slope of the end-diastolic pressure-volume relationship. Treatment with RAN attenuated these alterations and determined a reduction in mortality. Additionally, the magnitude of myocardial hypertrophy and activation of PI3K/Akt pathway were reduced. Alteration in diastolic compliance as a consequence of elevated myocardial stiffness was confirmed by an increase of collagen deposition and activation of pro-fibrotic TGF-ß/SMAD3/CTGF signaling. These effects were counteracted by RAN. High salt rats had a decrease in SERCA2 and an increase in Na(+)/Ca(2+) exchanger (NCX). Treatment with RAN reduced NCX expression and determined an increment of SERCA2. Moreover, the levels of nitrotyrosine and oxidized dyhydroethidium were higher in high salt rats. RAN induced a decrement of oxidative stress, supporting the concept that reduction in ROS may mediate beneficial effects. CONCLUSIONS: Our findings support the possibility that diastolic dysfunction can be attenuated by RAN, indicating its ability to affect active relaxation and passive diastolic compliance.

SIRT1 activation rescues doxorubicin-induced loss of functional competence of human cardiac progenitor cells.

BACKGROUND: The search for compounds able to counteract chemotherapy-induced heart failure is extremely important at the age of global cancer epidemic. The role of SIRT1 in the maintenance of progenitor cell homeostasis may contribute to its cardioprotective effects. SIRT1 activators, by preserving progenitor cells, could have a clinical relevance for the prevention of doxorubicin (DOXO)-cardiotoxicity. METHODS: To determine whether SIRT1 activator, resveratrol (RES), interferes with adverse effects of DOXO on cardiac progenitor cells (CPCs): 1) human CPCs (hCPCs) were exposed in vitro to DOXO or DOXO+RES and their regenerative potential was tested in vivo in an animal model of DOXO-induced heart failure; 2) the in vivo effects of DOXO+RES co-treatment on CPCs were studied in a rat model. RESULTS: In contrast to healthy cells, DOXO-exposed hCPCs were ineffective in a model of anthracycline cardiomyopathy. The in vitro activation of SIRT1 decreased p53 acetylation, overcame suppression of the IGF-1/Akt pro-survival and anti-apoptotic signaling, enhanced oxidative stress defense and prevented senescence and growth arrest of hCPCs. Priming with RES counterbalanced the onset of dysfunctional phenotype in DOXO-exposed hCPCs, partly restoring their ability to repair the damage with improvement in cardiac function and animal survival. The in vivo co-treatment DOXO+RES prevented the anthracycline-induced alterations in CPCs, partly preserving cardiac function. CONCLUSION: SIRT1 activation protects DOXO-exposed CPCs and re-establishes their proper function. Pharmacological intervention at the level of tissue-specific progenitor cells may provide cardiac benefits for the growing population of long-term cancer survivors that are at risk of chemotherapy-induced cardiovascular toxicity.