Characterization of p38α autophosphorylation inhibitors that target the non-canonical activation pathway.

p38α is a versatile protein kinase that can control numerous processes and plays important roles in the cellular responses to stress. Dysregulation of p38α signaling has been linked to several diseases including inflammation, immune disorders and cancer, suggesting that targeting p38α could be therapeutically beneficial. Over the last two decades, numerous p38α inhibitors have been developed, which showed promising effects in pre-clinical studies but results from clinical trials have been disappointing, fueling the interest in the generation of alternative mechanisms of p38α modulation. Here, we report the in silico identification of compounds that we refer to as non-canonical p38α inhibitors (NC-p38i). By combining biochemical and structural analyses, we show that NC-p38i efficiently inhibit p38α autophosphorylation but weakly affect the activity of the canonical pathway. Our results demonstrate how the structural plasticity of p38α can be leveraged to develop therapeutic opportunities targeting a subset of the functions regulated by this pathway.

Intravitreal Injections during the COVID-19 Outbreak in Northern Italy: An Innovative Approach for a High Quality and Safe Treatment.

BACKGROUND: Intravitreal injection (IVI) is a standard procedure performed in ophthalmology to treat several conditions, and is performed in different settings across countries. The Italian guidelines recommend this intervention is performed in an operating room to minimize the risk of infections, while in other countries, including Canada, USA and the UK, IVIs are performed in the ophthalmologist's office. The 2020 COVID-19 outbreak caused a dramatic modification in outpatient care. Consequently, non-urgent surgical activities, like IVIs, were subjected to a drastic reduction. METHODS: We conducted observational study which investigated the outcomes of IVIs performed in an ophthalmologist's office using a mobile laminar flow unit, the Operio mobile (Toul Meditech, Operio®) versus an operating room setting. RESULTS: Use of the Operio mobile allowed the safety performance of 3838 IVIs during COVID-19 and significantly reduced the waiting time of the first visit. This results in a faster intervention without affecting the technical IVI procedure that remained unchanged comparing the two settings. Specifically, we observed a 26% reduction in operation costs for each IVI performed in the office, which can be translated to a higher impact when considering the total number of IVIs performed over one year. CONCLUSION: The use of the Operio mobile in an ophthalmologist's office provides flexibility to perform IVIs, assuring patient safety, reducing healthcare personnel employment times, and the waiting lists for the patients, increasing the number of surgeries and improving the cost-effectiveness of the procedure.

Recruitment of arfaptins to the trans-Golgi network by PI(4)P and their involvement in cargo export.

The BAR (Bin/Amphiphysin/Rvs) domain proteins arfaptin1 and arfaptin2 are localized to the trans-Golgi network (TGN) and, by virtue of their ability to sense and/or generate membrane curvature, could play an important role in the biogenesis of transport carriers. We report that arfaptins contain an amphipathic helix (AH) preceding the BAR domain, which is essential for their binding to phosphatidylinositol 4-phosphate (PI(4)P)-containing liposomes and the TGN of mammalian cells. The binding of arfaptin1, but not arfaptin2, to PI(4)P is regulated by protein kinase D (PKD) mediated phosphorylation at Ser100 within the AH. We also found that only arfaptin1 is required for the PKD-dependent trafficking of chromogranin A by the regulated secretory pathway. Altogether, these findings reveal the importance of PI(4)P and PKD in the recruitment of arfaptins at the TGN and their requirement in the events leading to the biogenesis of secretory storage granules.