5mC-hydroxylase activity is influenced by the PARylation of TET1 enzyme

5-hydroxymethylcytosine is a new epigenetic modification deriving from the oxidation of 5-methylcytosine by the TET hydroxylase enzymes. DNA hydroxymethylation drives DNA demethylation events and is involved in the control of gene expression. Deregulation of TET enzymes causes developmental defects and is associated with pathological conditions such as cancer. Little information thus far is available on the regulation of TET activity by post-translational modifications. Here we show that TET1 protein is able to interact with PARP-1/ARTD1 enzyme and is target of both noncovalent and covalent PARylation. In particular, we have demonstrated that the noncovalent binding of ADP-ribose polymers with TET1 catalytic domain decreases TET1 hydroxylase activity while the covalent PARylation stimulates TET1 enzyme. In addition, TET1 activates PARP-1/ARTD1 independently of DNA breaks. Collectively, our results highlight a complex interplay between PARylation and TET1 which may be helpful in coordinating the multiple biological roles played by 5-hydroxymethylcytosine and TET proteins

Professionisti sanitari e cura del fine vita: lo studio E.L.D.Y. (End of Life Decisions studY)

Background. In developed societies, the main causes of death are represented by degenerative illnesses, and an increasing number of patients in intensive care yards remain in a coma or in a terminal phase for long time. In such a context, clinical decisions at the end of life are becoming more and more complex, and involve medical, psychological and ethical aspects. A multidisciplinary reflection on these problems increased the interest toward end-of-life issues in the national and international context, highlighting important changes in shared thoughts and different opinions on these topics by Italian professionals compared to European or American colleagues. Topics such as end-of-life decisions, cures and treatments in the terminal phase, respect for living will are increasingly present in the literature. However, only a few studies investigated these topics in the geriatric field, particularly in Italy. Aims. The E.L.D.Y. study (End of Life Decision studY) aims at: investigate the type and frequency of decisions taken, in the clinical practice during the terminal phase of patients’ life, by physicians and professional nurses, especially in the geriatric field in the Italian Regions Veneto, Trentino Alto-Adige and Marche; assess the opinions concerning end-of-life decisions by professionals involved in the assistance of elderly patients; analyze the possible associations between end-of-life opinions and individual characteristics; compare the obtained findings with those of similar studies previously conducted both in the Italian and in the European context. Materials and Methods. Through an articulated multidisciplinary work, a new questionnaire has been constructed, taking into account the critiques formulated to the previous national and international studies. The instrument was send to approximately 6000 physicians, nurses, psychologists and healthcare workers in elderly patients assistance units in Veneto, Trentino Alto-Adige and Marche Regions. The questionnaire was composed by three parts: the first, to be compiled by physicians and nurses only, concerned the decisions taken about the last death patient they assisted; the second, regarding health workers in general, aimed at investigating end-of-life related opinions; the third assessed some individual characteristics of the professionals. Results. Respondents were 1545 social and health workers: 301 physicians (MD), 788 registered nurses (RN), 231 healthcare workers, 108 psychologists; 117 were other workers in the structures. The questionnaires that met the selection criteria for the statistical analyses were 680 for end-of-life decisions and 1425 for the investigated opinions. A total of 161 decisions to end life (DEL) emerged (24% of deaths that did not occur suddenly and that professionals had the opportunity to follow). They were divided into 141 non-treatment decisions and 20 cases of medically assisted death. Among the latter, 2 were cases of euthanasia (MD: 1 and RN: 1), while 16 were cases of death suppression without explicit request by the patient (MD: 3 and RN: 13). Overall, 1.4% of physicians stated that they intervened directly and intentionally to anticipate the end of life. Fifty percent of physicians reported that they had started or not stopped a treatment taking into account the possibility that this action could have prolonged the patient’s life; the 31%, instead, reported that they did not start or that they stopped a treatment taking into account the possibility that this action could have hastened the death of a terminal ill patient. Concerning opinions, only a minority (26%) of physicians and nurses agree with the principle according to which there is not a right to die, while the majority (76%) agree with the right of a patient to decide on the possibility to hasten the end of life. About half of our respondents (52%) think that it is acceptable to use lethal drugs if requested by a terminally ill patient with untreatable suffering. About 60% of participants think that living will should always be respected, even if this could hasten death. Finally, the separation of the items concerning artificial nutrition and artificial hydration allowed us to observe that the latter is administered more frequently than the former, suggesting that artificial hydration only is considered as a basic form of care. Concerning communication, results indicate that physicians tend to discuss the proposed topics more with relatives than with patients, differently from what emerged in other European countries. Regarding differences between professionals, the main ones concern the answers provided by psychologists. The psychologists in our study, almost all from Triveneto, consistently with their professional role, tend to attribute particular importance to topics such as communication with patients, respect of their indications and will, and the act of listening in the relations with relatives. The main differences related to regional origin concern the administration of treatments such as artificial nutrition, dialysis and ventilation, that is considered as more necessary in Marche than in Triveneto. Conclusions. The conducted study presents some limitations: data concern three Italian Regions, two from the North and one in Central Italy and, therefore, in the future it would be useful to extend the investigation to other Italian Regions and possibly to other nations; many of our variables regard the opinions of respondents and not only their actual behaviours. Despite these limitations, this work is certainly useful to provide indications concerning fundamental problems of a clinical, psychological and ethical nature that health professionals encounter when facing end-of-life issues. Moreover, given the high percentages of respondents who reported interest toward the questionnaire, so as the absence of substantial criticisms, we can conclude that the aim of creating a new instrument, useful to effectively assess practices and opinions related to end-of-life in Italy, has been reached

Financial cycles, credit networks and macroeconomic fluctuations: multi-scale stochastic models and wavelet analysis

This project focuses on the macroeconomics of financial cycles. Usually defined in terms of self-reinforcing interactions between perceptions of value and risk, attitudes towards risk and financing constraints, which translate into booms followed by bust, the recent empirical literature has recurred to two approaches \u2013 turning point analysis and frequency-based filters - applied to measures of credit and asset prices to pose a number of stylized facts. First, financial cycles tend to display a greater amplitude and a lower frequency in comparison to business cycles, with peaks associated with systemic crises. Second, financial cycles depend on policy regimes and on the pace of financial innovations, leading to a wide cross-country heterogeneity and a time-varying degree of global synchronization. The latter point is clearly related to the structural transformations occurred in financial systems over the last three decades, like the cumulative integration of traditional banking with capital market developments and the increasing degree of interconnections among financial institutions. However, to date very little is known about determinants and mechanisms behind financial cycles, and on how they interact with business cycles and medium-to-long-run macroeconomic performance. In this project we plan to research along three dimensions: i) measurement issues, in order to provide a comprehensive assessment of the evolution of co-movements between financial and real variables across a sample of financial developed countries, both over time and at different frequencies; ii) theoretical issues, aimed at exploring under what circumstances the network of interconnections among financial intermediaries and between intermediaries and non-financial borrowers might evolve cyclically, contributing this way to regulate the incentives agents have in taking risks, and to set the importance of credit and financial frictions in accounting for time-varying misallocations of resources; iii) policy issues, given the role assigned by international supervisory bodies to a proper characterization and knowledge of the financial cycle as a prerequisite for the macro-prudential regulation of banks, and the scope of monetary policy in promoting financial stability in addition to the typical mandate of price stability. Our task requires the employment of a new approach to macroeconomic analysis, diverse analytical tools and one unifying economic principle. As regards the latter, our focal point is the notion of risk externalities, across financial institutions and between the financial sector and the real economy. The set of tools we plan to employ spans from wavelets methods to multi-scale models in continuous time, and from strategic network formation to agent-based computational techniques. All these tools are instrumental in building and estimating macroeconomic models characterized by interrelated markets operating at different time scales

Disuguaglianze di genere in una pandemia: un approccio economico

L’evidenza empirica più recente indica che le diseguaglianze di genere durante la pandemia da Covid-19 si sono accentuate. Questo lavoro, dopo aver esposto la concettualizzazione e la misurazione delle diseguaglianze di genere, esamina i principali meccanismi economici e comportamentali che, portando a una maggiore diseguaglianza, in seguito alla pandemia rischiano di azzerare i diritti faticosamente conquistati dalle donne.The latest empirical evidence shows that gender inequalities have been increasing during the Covid-19 pandemic. Starting from how inequalities are defined and measured, this paper addresses the issue of economic and social mechanisms which – by increasing gender inequalities, after the pandemic – are likely to jeopardize many of the rights conquered by women

Poly(ADP-ribosyl)ation is involved in the epigenetic control of TET1 gene transcription

TET enzymes are the epigenetic factors involved in the formation of the Sixth DNA base 5-hydroxymethylcytosine, whose deregulation has been associated with tumorigenesis. In particular, TET1 acts as tumor suppressor preventing cell proliferation and tumor metastasis and it has frequently been found down-regulated in cancer. Thus, considering the importance of a tight control of TET1 expression, the epigenetic mechanisms involved in the transcriptional regulation of TET1 gene are here investigated. The involvement of poly(ADP-ribosyl)ation in the control of DNA and histone methylation on TET1 gene was examined. PARP activity is able to positively regulate TET1 expression maintaining a permissive chromatin state characterized by DNA hypomethylation of TET1 CpG island as well as high levels of H3K4 trimethylation. These epigenetic modifications were affected by PAR depletion causing TET1 downregulation and in turn reduced recruitment of TET1 protein on HOXA9 target gene. In conclusion, this work shows that PARP activity is a transcriptional regulator of TET1 gene through the control of epigenetic events and it suggests that deregulation of these mechanisms could account for TET1 repression in cancer

PARP inhibitor ABT-888 affects response of MDA-MB-231 cells to doxorubicin treatment, targeting Snail expression

To overcome cancer cells resistance to pharmacological therapy, the development of new therapeutic approaches becomes urgent. For this purpose, the use of poly(ADP-ribose) polymerase (PARP) inhibitors in combination with other cytotoxic agents could represent an efficacious strategy. Poly(ADP-ribosyl)ation (PARylation) is a post-translational modification that plays a well characterized role in the cellular decisions of life and death. Recent findings indicate that PARP-1 may control the expression of Snail, the master gene of epithelial-mesenchymal transition (EMT). Snail is highly represented in different resistant tumors, functioning as a factor regulating anti-apoptotic programmes. MDA-MB-231 is a Snail-expressing metastatic breast cancer cell line, which exhibits chemoresistance properties when treated with damaging agents. In this study, we show that the PARP inhibitor ABT-888 was capable to modulate the MDA-MB-231 cell response to doxorubicin, leading to an increase in the rate of apoptosis. Our further results indicate that PARP-1 controlled Snail expression at transcriptional level in cells exposed to doxorubicin. Given the increasing interest in the employment of PARP inhibitors as chemotherapeutic adjuvants, our in vitro results suggest that one of the mechanisms through which PARP inhibition can chemosensitize cancer cells in vivo, is targeting Snail expression thus promoting apoptosi

Ancient DNA: genomic amplification of Roman and medieval bovine bones.

Cattle remains (bones and teeth) of both roman and medieval age were collected in the archaeological site of Ferento (Viterbo, Italy) with the aim of extracting and characterising nucleic acids. Procedures to minimize contamination with modern DNA and to help ancient DNA (aDNA) preservation of the archaeological remains were adopted. Different techniques to extract aDNA (like Phenol/chloroform extraction) from bovine bones were tested to identify the method that applies to the peculiar characteristics of the study site. Currently, aDNA investigation is mainly based on mtDNA, due to the ease of amplification of the small and high-copied genome and to its usefulness in evolutionary studies. Preliminary amplification of both mitochondrial and nuclear aDNA fragments from samples of Roman and medieval animals were performed and partial specific sequences of mitochondrial D-loop as well as of nuclear genes were obtained. The innovative amplification of nuclear aDNA could enable the analysis of genes involved in specific animal traits, giving insights of ancient economic and cultural uses, as well as providing information on the origin of modern livestock population

DNA hydroxymethylation levels are altered in blood cells from Down syndrome persons enrolled in the MARK-AGE project

Down syndrome (DS) is caused by the presence of part or an entire extra copy of chromosome 21, a phenomenon that can cause a wide spectrum of clinically defined phenotypes of the disease. Most of the clinical signs of DS are typical of the ageing process including dysregulation of immune system. Beyond the causative genetic defect, DS persons display epigenetic alterations, particularly aberrant DNA methylation patterns that can contribute to the heterogeneity of the disease. In the present work we investigated the levels of 5-hydroxymethylcytosine (5hmC) and of the TET dioxygenase enzymes, which are involved in DNA demethylation processes and are often deregulated in pathological conditions as well as in ageing. Analyses were carried out on peripheral blood mononuclear cells of DS volunteers enrolled in the context of the MARK-AGE study, a large-scale cross-sectional population study with subjects representing the general population in eight European countries. We observed a decrease of 5hmC, TET1 and other components of the DNA methylation/demethylation machinery in DS subjects, indicating that aberrant DNA methylation patterns in DS, which may have consequences on the transcriptional status of immune cells, may be due to a global disturbance of methylation control in DS