Increase of telomerase activity and hTERT expression in myelodysplastic syndromes

Telomerase enzyme, containing a catalytic subunit, the human telomerase reverse transcriptase (hTERT), and a small integral RNA component, synthesises the telomeres, the ends of eukaryotic chromosomes. Inhibition of telomerase activity leads the cells to senescence and death. Myelodysplastic syndromes (MSD) are hematological malignancies characterized by peripheral blood cytopenia and ineffective hematopoiesis. Telomerase activity and hTERT expression in MDS patients were independently investigated by different groups obtaining contradictory results. We analyzed telomerase activity and hTERT expression in the bone marrow of ten control, 15 MDS patients and two patients with AML, likely evolved from a previous MDS. Moreover, the expression of c-myc, mad1, p53 (transcription factors involved in hTERT expression regulation), has been investigated. Telomerase activity and hTERT expression increased in the MDS patients with respect to the controls. The analysis of the MDS subgroups, indicated that patients with more severe disease demonstrated significantly higher levels of hTERT expression and telomerase activity with respect to the patients with more favorable disease. c-Myc and p53 expressions were not significantly different between controls and MDS patients, whereas mad1 expression was increased in MDS patiens, particularly in those with more favorable disease. We hypothesize that mad1 increase can contribute to reduce the hTERT expression in the early stage of disease and we suggest that hTERT expression and telomerase activity, whether confirmed in larger series of cases could support other parameters in the diagnosis and stadiation of MDS

Contribution of ultrarare variants in mTOR pathway genes to sporadic focal epilepsies

Objective: We investigated the contribution to sporadic focal epilepsies (FE) of ultrarare variants in genes coding for the components of complexes regulating mechanistic Target Of Rapamycin (mTOR)complex 1 (mTORC1). Methods: We collected genetic data of 121 Italian isolated FE cases and 512 controls by Whole Exome Sequencing (WES) and single-molecule Molecular Inversion Probes (smMIPs) targeting 10 genes of the GATOR1, GATOR2, and TSC complexes. We collapsed “qualifying” variants (ultrarare and predicted to be deleterious or loss of function) across the examined genes and sought to identify their enrichment in cases compared to controls. Results: We found eight qualifying variants in cases and nine in controls, demonstrating enrichment in FE patients (P = 0.006; exact unconditional test, one-tailed). Pathogenic variants were identified in DEPDC5 and TSC2, both major genes for Mendelian FE syndromes. Interpretation: Our findings support the contribution of ultrarare variants in genes in the mTOR pathway complexes GATOR and TSC to the risk of sporadic FE and a shared genetic basis between rare and common epilepsies. The identification of a monogenic etiology in isolated cases, most typically encountered in clinical practice, may offer to a broader community of patients the perspective of precision therapies directed by the underlying genetic cause

Quantitative Organization of GABAergic Synapses in the Molecular Layer of the Mouse Cerebellar Cortex

In the cerebellar cortex, interneurons of the molecular layer (stellate and basket cells) provide GABAergic input to Purkinje cells, as well as to each other and possibly to other interneurons. GABAergic inhibition in the molecular layer has mainly been investigated at the interneuron to Purkinje cell synapse. In this study, we used complementary subtractive strategies to quantitatively assess the ratio of GABAergic synapses on Purkinje cell dendrites versus those on interneurons. We generated a mouse model in which the GABAA receptor α1 subunit (GABAARα1) was selectively removed from Purkinje cells using the Cre/loxP system. Deletion of the α1 subunit resulted in a complete loss of GABAAR aggregates from Purkinje cells, allowing us to determine the density of GABAAR clusters in interneurons. In a complementary approach, we determined the density of GABA synapses impinging on Purkinje cells using α-dystroglycan as a specific marker of inhibitory postsynaptic sites. Combining these inverse approaches, we found that synapses received by interneurons represent approximately 40% of all GABAergic synapses in the molecular layer. Notably, this proportion was stable during postnatal development, indicating synchronized synaptogenesis. Based on the pure quantity of GABAergic synapses onto interneurons, we propose that mutual inhibition must play an important, yet largely neglected, computational role in the cerebellar cortex

Clinical Features, Cardiovascular Risk Profile, and Therapeutic Trajectories of Patients with Type 2 Diabetes Candidate for Oral Semaglutide Therapy in the Italian Specialist Care

Introduction: This study aimed to address therapeutic inertia in the management of type 2 diabetes (T2D) by investigating the potential of early treatment with oral semaglutide. Methods: A cross-sectional survey was conducted between October 2021 and April 2022 among specialists treating individuals with T2D. A scientific committee designed a data collection form covering demographics, cardiovascular risk, glucose control metrics, ongoing therapies, and physician judgments on treatment appropriateness. Participants completed anonymous patient questionnaires reflecting routine clinical encounters. The preferred therapeutic regimen for each patient was also identified. Results: The analysis was conducted on 4449 patients initiating oral semaglutide. The population had a relatively short disease duration (42%  60% of patients, and more often than sitagliptin or empagliflozin. Conclusion: The study supports the potential of early implementation of oral semaglutide as a strategy to overcome therapeutic inertia and enhance T2D management