The light and shadow of senescence and inflammation in cardiovascular pathology and regenerative medicine

Recent epidemiologic studies evidence a dramatic increase of cardiovascular diseases, especially associated with the aging of the world population. During aging, the progressive impairment of the cardiovascular functions results from the compromised tissue abilities to protect the heart against stress. At the molecular level, in fact, a gradual weakening of the cellular processes regulating cardiovascular homeostasis occurs in aging cells. Atherosclerosis and heart failure are particularly correlated with aging-related cardiovascular senescence, that is, the inability of cells to progress in the mitotic program until completion of cytokinesis. In this review, we explore the intrinsic and extrinsic causes of cellular senescence and their role in the onset of these cardiovascular pathologies. Additionally, we dissect the effects of aging on the cardiac endogenous and exogenous reservoirs of stem cells. Finally, we offer an overview on the strategies of regenerative medicine that have been advanced in the quest for heart rejuvenation

The effects of painless nerve growth factor on human microglia polarization

Previous studies in the rat suggest that microglial cells represent a potential druggable target for nerve growth factor (NGF) in the brain. The painless human Nerve Growth Factor (hNGFp) is a recombinant mutated form of human nerve growth factor (hNGF) that shows identical neurotrophic and neuroprotective properties of wild-type NGF but displays at least 10-fold lower algogenic activity. From the pharmacological point of view, hNGFp is a biased tropomyosin receptor kinase A (TrkA) agonist and displays a significantly lower affinity for the p75 neurotrophin receptor (p75NTR). This study aimed to evaluate the expression of TrkA and p75NTR NGF receptors in two different human microglia cell lines, and to investigate the effects of hNGFp and wild-type NGF (NGF) on L-arginine metabolism, taken as a marker of microglia polarization. Both NGF receptors are expressed in human microglia cell lines and are effective in transducing signals triggered by NGF and hNGFp. The latter and, to a lesser extent, NGF inhibit cytokine-stimulated inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) production in these cells. Conversely NGF but not hNGFp stimulates arginase-mediated urea production

A review of the molecular mechanisms underlying the development and progression of cardiac remodeling

Pathological molecular mechanisms involved in myocardial remodeling contribute to alter the existing structure of the heart, leading to cardiac dysfunction. Among the complex signaling network that characterizes myocardial remodeling, the distinct processes are myocyte loss, cardiac hypertrophy, alteration of extracellular matrix homeostasis, fibrosis, defective autophagy, metabolic abnormalities, and mitochondrial dysfunction. Several pathophysiological stimuli, such as pressure and volume overload, trigger the remodeling cascade, a process that initially confers protection to the heart as a compensatory mechanism. Yet chronic inflammation after myocardial infarction also leads to cardiac remodeling that, when prolonged, leads to heart failure progression. Here we review the molecular pathways involved in cardiac remodeling, with particular emphasis on those associated with myocardial infarction. A better understanding of cell signaling involved in cardiac remodeling may support the development of new therapeutic strategies towards the treatment of heart failure and reduction of cardiac complications. We will also discuss data derived from gene therapy approaches for modulating key mediators of cardiac remodeling

Association between High Normal TSH Levels and Obesity in Women with Anti-Thyroid Autoantibodies (ATAs)

A positive correlation between Thyroid-Stimulating Hormone (TSH) and Body Mass Index (BMI) has been reported in many studies, but data on this topic remain controversial, especially when TSH values are in the normal range. Moreover, few studies have evaluated the co-existence of thyroid autoimmunity. This study investigated the role of thyroid autoimmunity in the interconnection between TSH, BMI, and waist circumference (WC) in euthyroid patients with overweight or obesity. We enrolled 902 patients (213 males; mean age +/- SD: 45 +/- 14 years; mean BMI +/- SD: 35.8 +/- 6.5 kg/m(2)), with normal serum TSH concentration; anti-thyroid autoantibodies (ATAs) were evaluated in 752 patients (186 males). Patients were divided into four BMI classes, based on WHO criteria, and the relationship between BMI, WC, and TSH was evaluated in the whole sample and compared to ATAs positivity, observed in 235 patients (44 males). No significant difference was found between TSH levels in the BMI classes. A statistically significant correlation between TSH and BMI was found only in ATAs-positive females (N = 191, Spearman rho: 0.149; p-value: 0.040). However, this finding was not confirmed when considering the WC. Our study shows a positive correlation only between TSH and BMI in obese women with positive ATAs, suggesting that in these patients, the high normal levels of TSH could be attributed to a mild thyroid failure with a possible worsening obesity-related effect, and both need a careful evaluation

The impact of environmental factors in influencing epigenetics related to oxidative states in the cardiovascular system

Oxidative states exert a significant influence on a wide range of biological and molecular processes and functions. When their balance is shifted towards enhanced amounts of free radicals, pathological phenomena can occur, as the generation of reactive oxygen species (ROS) in tissue microenvironment or in the systemic circulation can be detrimental. Epidemic chronic diseases of western societies, such as cardiovascular disease, obesity, and diabetes correlate with the imbalance of redox homeostasis. Current advances in our understanding of epigenetics have revealed a parallel scenario showing the influence of oxidative stress as a major regulator of epigenetic gene regulation via modification of DNA methylation, histones, and microRNAs. This has provided both the biological link and a potential molecular explanation between oxidative stress and cardiovascular/metabolic phenomena. Accordingly, in this review, we will provide current insights on the physiological and pathological impact of changes in oxidative states on cardiovascular disorders, by specifically focusing on the influence of epigenetic regulation. A special emphasis will highlight the effect on epigenetic regulation of human's current life habits, external and environmental factors, including food intake, tobacco, air pollution, and antioxidant-based approaches. Additionally, the strategy to quantify oxidative states in humans in order to determine which biological marker could best match a subject's profile will be discussed

Review of solar energetic particle models

Solar Energetic Particle (SEP) events are interesting from a scientific perspective as they are the product of a broad set of physical processes from the corona out through the extent of the heliosphere, and provide insight into processes of particle acceleration and transport that are widely applicable in astrophysics. From the operations perspective, SEP events pose a radiation hazard for aviation, electronics in space, and human space exploration, in particular for missions outside of the Earth’s protective magnetosphere including to the Moon and Mars. Thus, it is critical to improve the scientific understanding of SEP events and use this understanding to develop and improve SEP forecasting capabilities to support operations. Many SEP models exist or are in development using a wide variety of approaches and with differing goals. These include computationally intensive physics-based models, fast and light empirical models, machine learning-based models, and mixed-model approaches. The aim of this paper is to summarize all of the SEP models currently developed in the scientific community, including a description of model approach, inputs and outputs, free parameters, and any published validations or comparisons with data.</p

Functional role of Nox4 in autophagy

Accumulating lines of evidence suggest that reactive oxygen species (ROS) may act as intracellular signaling molecules under cellular stress conditions, activating several molecular pathways. Autophagy, the intracellular mechanism by which cells digest and recycle unfolded proteins and dysfunctional organelles, is emerging as a major target of ROS and NADPH oxidase (Nox) enzymes, the major generators of ROS. While autophagy represents an important self-defense mechanism in promoting cell survival, it may be maladaptive in some conditions. In particular, in the cardiovascular system, moderate activation of autophagy has been shown to be protective, while excessive or insufficient activation of autophagy may be deleterious. Thus, modulating ROS-dependent autophagy may represent a novel strategy to keep autophagy within the therapeutic range. Among the Nox isoforms, Nox4 in particular plays a pivotal role in autophagy regulation. This appears to be due to its intracellular localization and its ability to produce hydrogen peroxide, a stable signaling molecule. In this chapter we review the studies relating to the functional role of Nox4 in autophagy, with particular emphasis on the heart and cardiovascular system

Mitochondrial complex I deficiency and cardiovascular diseases. current evidence and future directions

Compelling evidence demonstrates the emerging role of mitochondrial complex I deficiency in the onset and development of cardiovascular diseases (CVDs). In particular, defects in single subunits of mitochondrial complex I have been associated with cardiac hypertrophy, ischemia/reperfusion injury, as well as diabetic complications and stroke in pre-clinical studies. Moreover, data obtained in humans revealed that genes coding for complex I proteins were associated with different CVDs. In this review, we discuss recent experimental studies that underline the contributory role of mitochondrial complex I deficiency in the etiopathogenesis of several CVDs, with a particular focus on those involving loss of function models of mitochondrial complex I. We also discuss human studies and potential therapeutic strategies able to rescue mitochondrial function in CVDs

Study Design and Rationale for Espera Trial: A Multicentre, Randomized, Phase II Clinical Trial Evaluating the Potential Efficacy of Adding SBRT to Pembrolizumab-Pemetrexed Maintenance in Responsive or Stable Advanced Non-Squamous NSCLC After Chemo-Immunotherapy Induction

Background: Improvement in radiotherapy techniques and expected outcomes, as well as in understanding the underlying biological mechanisms contributing to its action (immunomodulation in primis), led to the integration of this therapeutical approach in the current management of advanced non-small cell lung cancer (NSCLC), not only in oncogene-driven tumors, but also in non-oncogene addicted NSCLC where the combination of platinum-based chemotherapy plus pembrolizumab represents nowadays the pivotal strategy. In this light, we have designed a randomized phase II (ESPERa) trial to evaluate the efficacy and safety of adding Stereotactic Body Radiotherapy (SBRT) to pembrolizumab-pemetrexed maintenance in advanced NSCLC patients experiencing disease response or stability after chemo-immunotherapy induction. Patients and methods: Advanced non-oncogene addicted NSCLC patients with ECOG performance status of 0 or 1, who obtained disease response or stability after 4 cycles of platinum-based chemotherapy plus pembrolizumab will be randomized 2:1 to receive pembrolizumab-pemetrexed maintenance plus SBRT vs pembrolizumab-pemetrexed alone. The primary endpoint is progression-free survival (PFS). Concomitant translational researches will be performed to identify potential prognostic and/or predictive biomarkers, as well as to analyze and monitor tumour microenvironment and tumor-host interactions. Conclusions: Although available data suggest the safety and efficacy of combining immunotherapy and radiotherapy, their systematic integration in the current first-line landscape still remains to be explored. If the pre-planned endpoints of the ESPERa trial will be achieved, the addition of SBRT to pembrolizumab-pemetrexed maintenance as a strategy to consolidate and ideally improve the awaited benefit could be considered as a promising strategy in NSCLC undergoing first-line therapy, as well as an interesting approach to be evaluated in other disease setting, as well as in other oncological malignancies where immunotherapy represents nowadays the standard-of-care