Zebrafish embryo extract counteracts human stem cell senescence.

Human adult stem cells hold promise for regenerative medicine. They are usually expanded for multiple passages in vitro to increase cell yield prior to transplantation. Unfortunately, prolonged culture leads to cell senescence, a major drawback from successful outcomes in cell therapy approaches. Here, we show that an extract from early Zebrafish embryo (ZF1) counteracted senescence progression in human adipose-derived stem cells (hASCs) along multiple culture passages (from the 5th to the 20th). Exposure to ZF1 strongly reduced the expression of senescence marker beta-galactosidase. Both stemness (NANOG, OCT4, and MYC) and anti-senescence (BMI1, and telomerase reverse transcriptase - TERT) related genes were overexpressed at specific experimental points, without recruitment of the cyclin-dependent kinase Inhibitor 2A (CDKN2A, ali-as p16). Increased telomerase activity was associatt-ed with TERT overexpression. Both osteogenic and adipogenic abilities were enhanced. In conclusion, hASCs exposure to ZF1 is a feasible tool to counteract and reverse human stem cell senescence in long-term culturing conditions.

Unbiased pro-thrombotic features at diagnosis in 977 thrombocythemic patients with Philadelphia-negative chronic myeloproliferative neoplasms.

In patients with Philadelphia-negative chronic myeloproliferative neoplasms (MPNs), the anti-thrombotic and/or cytoreductive treatment in the follow-up may affect the evaluation of the pro-thrombotic weight of the clinical and biological characteristics at diagnosis. In order to avoid this potential confounding effect, we investigated the relationship between prior thrombosis (PrTh: thrombosis occurred before diagnosis and before treatment) and the characteristics at diagnosis in 977 thrombocythemic patients with MPN, reclassified according to the WHO 2008 criteria. PrTh occurred in 194 (19.9%) patients, with similar rates in the different MPNs. In multivariate analysis, PrTh rate was significantly related to minor thrombocytosis (platelets ≤700×10(9)/L), leukocytosis (leukocytes >10×10(9)/L), higher hematocrit (HCT >45%), JAK2 V617F mutation, older age, and cardiovascular risk factors (CVRFs). The highest PrTh rate (33.9%) was associated with the coexistence of minor thrombocytosis and leukocytosis. Of note, the inverse relationship between PrTh rate and platelet count is consistent with the hemostatic paradox of thrombocytosis. In conclusion, this analysis in MPN patients disclosed the unbiased characteristics at diagnosis with a pro-thrombotic effect. Moreover, it suggests that the optimal control of blood cells counts, and CVRFs might be of utmost importance in the prevention of thrombosis during the follow-up.

Anagrelide treatment and cardiovascular monitoring in essential thrombocythemia. A prospective observational study.

In this prospective observational single-center study, 55 patients with essential thrombocythemia who were candidates for second line treatment with anagrelide (ANA) received a preliminary cardiovascular (CV) clinical, instrumental and biochemical evaluation (CV history and symptoms, CV risk factors, blood pressure, heart rate, ECG and ECHO-cardio parameters, Troponin I, NT-proBNP). After this in-depth CV screening, 54 out of 55 patients were deemed to be fit for ANA treatment. Thirty-eight of the 55 patients received ANA treatment for a median of 36 months (range 3-48), and were monitored using the same CV evaluation. Fourteen of these 38 patients manifested CV adverse events (10 palpitation, 4 edema, 2 arterial hypertension, 2 acute myocardial infarction) that were not predicted by the in-depth CV evaluation, and that led to ANA withdrawal in only one case (non-cardiac refractory edema). In conclusion, the planned in-depth CV evaluation did not appear to be necessary in ET patients to evaluate their suitability for ANA treatment, and, moreover, was not able to predict the occurrence of CV adverse events during ANA treatment. Nevertheless, the CV adverse events (mostly palpitations and edema) were easily managed by the hematologists, and required the cardiologist involvement in very few selected cases.