New perspectives in the mechanisms of aging in animals

In recent years, the study of aging process in humans and animals has progressed rapidly, mainly due to the advent of new research instruments and our increasing liability to assemble large, complex data sets acquired across several approaches into an integrated representation of neural and muscular function at the molecular, cellular, and systemic levels. The overall aim of my Ph.D. thesis was to describe the age-related morphological changes in brain and skeletal muscle of cattle and to investigate some of the mechanisms and pathways underlying the aging process of Central Nervous System. First, I describe morphological changes of brain tissue and skeletal muscle associated with old age. Second, I report our studies on autophagy, a highly regulated process involving the bulk degradation of cytoplasmic macromolecules and the possible consequences of the intraneuronal accumulation of lipofuscin, amyloid precursor protein (APP) and increased reactive oxygen species (ROS) on autophagy machinery. Finally, I present the results of our researches concerning one on the most recognized effects of aging: the “immunosenescence”, the dysregulation of the immune system as a result of defects in both initiation and resolution of immune responses. Specifically, we investigated the expression of one of the major “culprits” of neuroinflammation, the NALP3 inflammasome and its association with autophagy and increased ROS production. Our results indicate that changes such as satellitosis, lipofuscin accumulation and central chromatolysis are quite consistent in bovine brains, although it is still debatable whether call them pathologic lesions or simply physiologic age-related alteration. Moreover, we confirm the presence of age-related morphologic changes in skeletal muscle of cows similar to human sarcopenia and underline the possible role of amyloid deposition and subsequent inflammation in muscle senescence. In aged bovine, autophagy is significantly impaired if compared to young animals. In our opinion, this data suggest that the increased age-related intraneuronal deposition of APP and lipofuscin may have an important role on the age-related autophagy impairment. Consistent with the recent scientific literature, our findings showed an increased expression of NLRP3 inflammasome in neurons and microglial cells of aged brains when compared with younger, indicating that the NLRP3 inflammasome is up-regulated in the brain as a result of aging. We also report a direct association between NLRP3 inflammasome, Superoxide Dismutase 1 (SOD1) and autophagy marker Beclin 1. The consequences of the autophagy and inflammasomes interplay are still poorly understood. Our results led us to hypothesize that the increased ROS production may activate inflammasomes provoking a low‐grade inflammation thus accelerating the aging process. Furthermore, the activation of inflammasomes may lead to an induction of autophagy that work to limit inflammasome activity by physical engulfment. This Ph.D thesis is the outcome of several experiments, all aimed to elucidate the molecular mechanisms resulting in morphologic and/or clinical age-related alterations of brain and skeletal muscle in cows. Our ultimate goal is to improve our understanding of aging with more detailed studies and, possibly, include bovine as a valuable animal model for the study of brain aging, sarcopenia and other age-related alterations

Interleukin 6 reduces vascular smooth muscle cell apoptosis via Prep1 and is associated with aging

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Bone Marrow Edema: Overview of Etiology and Treatment Strategies

➤: Bone marrow edema (BME) is a nonspecific but relevant finding, usually indicating the presence of an underlying pathology. ➤: The gold standard technique for detecting BME is magnetic resonance imaging (MRI), as it allows for a correct diagnosis to be made, which is extremely important given the heterogeneity of BME-related diseases. ➤: Depending on the severity of painful symptomatology and the MRI evidence, different treatment strategies can be followed: physical modalities, pharmacological options, and surgical therapy

Mouse Models in Prostate Cancer Translational Research: From Xenograft to PDX

Despite the advancement of clinical and preclinical research on PCa, which resulted in the last five years in a decrement of disease incidence by 3-4%, it remains the most frequent cancer in men and the second for mortality rate. Based on this evidence we present a brief dissertation on numerous preclinical models, comparing their advantages and disadvantages; among this we report the PDX mouse models that show greater fidelity to the disease, in terms of histopathologic features of implanted tumor, gene and miRNA expression, and metastatic pattern, well describing all tumor progression stages; this characteristic encourages the translation of preclinical results. These models become particularly useful in meeting the need of new treatments identification that eradicate PCa bone metastases growing, clarifying pathway of angiogenesis, identifying castration-resistant stem-like cells, and studying the antiandrogen therapies. Also of considerable interest are the studies of 3D cell cultures derived from PDX, which have the ability to maintain PDX cell viability with continued native androgen receptor expression, also showing a differential sensitivity to drugs. 3D PDX PCa may represent a diagnostic platform for the rapid assessment of drugs and push personalized medicine. Today the development of preclinical models in vitro and in vivo is necessary in order to obtain increasingly reliable answers before reaching phase III of the drug discovery

Ccdc6 knock-in mice develop thyroid hyperplasia associated to an enhanced CREB1 activity

CCDC6 was originally identified upon rearrangement with RET in human thyroid papillary carcinomas generating the RET/PTC1 oncogene. We have previously reported that CCDC6 interacts with CREB1 and represses its transcriptional activity. Since the function of at least one allele of CCDC6 is lost following RET/PTC1 rearrangements, we aimed at the generation of mice, carrying a CCDC6 mutant gene. Previous studies suggested that the coiled-coil domain of CCDC6, mainly encoded by human exon 2, is required for the protein function. Therefore, we engineered a murine Ccdc6 construct, carrying a deletion of the exon 2, that was able to exert only a mild repression on CREB1 transcriptional activity, with respect to the wild type Ccdc6. Subsequently, we generated Ccdc6-ex2 knock-in mice. These mice developed thyroid hyperplasia associated with an enhanced CREB1 activity and an increased expression of the CREB-1 regulated genes. These results strongly support a CCDC6 promoting role, ascribed to its functional impairment, in the development of thyroid papillary carcinomas harboring the RET/PTC1 oncogene

COVID-19 Severity in Multiple Sclerosis: Putting Data Into Context

Background and objectives: It is unclear how multiple sclerosis (MS) affects the severity of COVID-19. The aim of this study is to compare COVID-19-related outcomes collected in an Italian cohort of patients with MS with the outcomes expected in the age- and sex-matched Italian population. Methods: Hospitalization, intensive care unit (ICU) admission, and death after COVID-19 diagnosis of 1,362 patients with MS were compared with the age- and sex-matched Italian population in a retrospective observational case-cohort study with population-based control. The observed vs the expected events were compared in the whole MS cohort and in different subgroups (higher risk: Expanded Disability Status Scale [EDSS] score > 3 or at least 1 comorbidity, lower risk: EDSS score ≤ 3 and no comorbidities) by the χ2 test, and the risk excess was quantified by risk ratios (RRs). Results: The risk of severe events was about twice the risk in the age- and sex-matched Italian population: RR = 2.12 for hospitalization (p < 0.001), RR = 2.19 for ICU admission (p < 0.001), and RR = 2.43 for death (p < 0.001). The excess of risk was confined to the higher-risk group (n = 553). In lower-risk patients (n = 809), the rate of events was close to that of the Italian age- and sex-matched population (RR = 1.12 for hospitalization, RR = 1.52 for ICU admission, and RR = 1.19 for death). In the lower-risk group, an increased hospitalization risk was detected in patients on anti-CD20 (RR = 3.03, p = 0.005), whereas a decrease was detected in patients on interferon (0 observed vs 4 expected events, p = 0.04). Discussion: Overall, the MS cohort had a risk of severe events that is twice the risk than the age- and sex-matched Italian population. This excess of risk is mainly explained by the EDSS score and comorbidities, whereas a residual increase of hospitalization risk was observed in patients on anti-CD20 therapies and a decrease in people on interferon

DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR = 2.05, 95%CI = 1.39–3.02, p < 0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR = 0.42, 95%CI = 0.18–0.99, p = 0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon