Targeted Protein Degradation for Infectious Diseases: from Basic Biology to Drug Discovery

Targeted protein degradation (TPD) is emerging as one of the most innovative strategies to tackle infectious diseases. Particularly, proteolysis-targeting chimera (PROTAC)-mediated protein degradation may offer several benefits over classical anti-infective small-molecule drugs. Because of their peculiar and catalytic mechanism of action, anti-infective PROTACs might be advantageous in terms of efficacy, toxicity, and selectivity. Importantly, PROTACs may also overcome the emergence of antimicrobial resistance. Furthermore, anti-infective PROTACs might have the potential to (i) modulate "undruggable"targets, (ii) "recycle"inhibitors from classical drug discovery approaches, and (iii) open new scenarios for combination therapies. Here, we try to address these points by discussing selected case studies of antiviral PROTACs and the first-in-class antibacterial PROTACs. Finally, we discuss how the field of PROTAC-mediated TPD might be exploited in parasitic diseases. Since no antiparasitic PROTAC has been reported yet, we also describe the parasite proteasome system. While in its infancy and with many challenges ahead, we hope that PROTAC-mediated protein degradation for infectious diseases may lead to the development of next-generation anti-infective drugs

From Monoamine Oxidase Inhibition to Antiproliferative Activity: New Biological Perspectives for Polyamine Analogs

Monoamine oxidases (MAOs) are well-known pharmacological targets in neurological and neurodegenerative diseases. However, recent studies have revealed a new role for MAOs in certain types of cancer such as glioblastoma and prostate cancer, in which they have been found overexpressed. This finding is opening new frontiers for MAO inhibitors as potential antiproliferative agents. In light of our previous studies demonstrating how a polyamine scaffold can act as MAO inhibitor, our aim was to search for novel analogs with greater inhibitory potency for human MAOs and possibly with antiproliferative activity. A small in-house library of polyamine analogs (2-7) was selected to investigate the effect of constrained linkers between the inner amine functions of a polyamine backbone on the inhibitory potency. Compounds 4 and 5, characterized by a dianiline (4) or dianilide (5) moiety, emerged as the most potent, reversible, and mainly competitive MAO inhibitors (Ki < 1 μM). Additionally, they exhibited a high antiproliferative activity in the LN-229 human glioblastoma cell line (GI50 < 1 μM). The scaffold of compound 5 could represent a potential starting point for future development of anticancer agents endowed with MAO inhibitory activity

A Complete Meteo/Hydro/Hydraulic Chain Application to Support Early Warning and Monitoring Systems: The Apollo Medicane Use Case

Because of the ongoing changing climate, extreme rainfall events’ frequency at the global scale is expected to increase, thus resulting in high social and economic impacts. A Meteo/Hydro/Hydraulic forecasting chain combining heterogeneous observational data sources is a crucial component for an Early Warning System and is a fundamental asset for Civil Protection Authorities to correctly predict these events, their effects, and put in place anticipatory actions. During the last week of October 2021 an intense Mediterranean hurricane (Apollo) affected many Mediterranean countries (Tunisia, Algeria, Malta, and Italy) with a death toll of seven people. The CIMA Meteo/Hydro/Hydraulic forecasting chain, including the WRF model, the hydrological model Continuum, the automatic system for water detection (AUTOWADE), and the hydraulic model TELEMAC-2D, was operated in real-time to predict the Apollo weather evolution as well as its hydrological and hydraulic impacts, in support of the early warning activities of the Italian Civil Protection Department. The WRF model assimilating radar data and in situ weather stations showed very good predictive capability for rainfall timing and location over eastern Sicily, thus supporting accurate river flow peak forecasting with the hydrological model Continuum. Based on WRF predictions, the daily automatic system for water detection (AUTOWADE) run using Sentinel 1 data was anticipated with respect to the scheduled timing to quickly produce a flood monitoring map. Ad hoc tasking of the COSMO-SkyMed satellite constellation was also performed to overcome the S1 data latency in eastern Sicily. The resulting automated operational mapping of floods and inland waters was integrated with the subsequent execution of the hydraulic model TELEMAC-2D to have a complete representation of the flooded area with water depth and water velocity

Thermo- and photo- oxidation reaction scheme in a treatment system using submerged plasma

International audienceSome of hazardous liquid organic wastes, radioactive or not, are waiting from outlet to be destroyed. The ELIPSE process is a new technology of organic liquid destruction, involving a thermal plasma working under a water column, which ensures the cooling, the filtration and the scrubbing of the gases coming from the degradation. This study deals with the ability of the ELIPSE process to destroy the pure organic liquids and then to reduce the amount of organic matter remaining in the aqueous solution by means of the thermal or radiative properties of plasma. Preliminary test have shown how efficient the process is for the destruction of the organic liquids when they are directly fed in the plasma hearth. Extensive researches have been performed to assess the ability of the submerged plasma to destroy the remaining organic matters either by reinjecting them with the aqueous solution into the plasma or by using the UV ray coming from the plasma itself. A comparison of the experimental results obtained with various mechanisms proposed by the work carried out highlighted that this UV radiation could, by excitation of water molecules, produce radicals OH which may either dimerise to produce hydrogen peroxide H$_2$O$_2$, or react with organic substances present. The calculation of an activation energy of 8.5 $\pm$ 0.9 kJ mol$^{−1}$ during the experiments shows that these radicals OH$^\circ$ act directly after having been formed which explains a low H$_2$O$_2$ content stability when the solution contains organic compounds. Thus, this photo-oxidation taking place in the water column could be used to improve the destruction of residual organic matter in the solution by maintaining the plasma after processing a given amount of organic liquids

NEWLY SYNTHESIZED POLYAMINE DERIVATIVES AS POTENTIAL ANTICANCER AGENTS

Natural polyamines are nitrogen-bearing aliphatic chains that play an essential role in cell growth and differentiation and represent physiological sources of polycations necessary for stabilization of DNA topologies. Polyamine content in the cells is tightly regulated: in addition to synthesis, mammalian cells are equipped with an efficient polyamine uptake system, whose activity is proportional to cell proliferation. Polyamines analogues and derivatives can suppress proliferation of cancer cells by inhibition of the biosynthesis of natural polyamines and can exert cytotoxic activity due to their DNA-binding properties. Many tumour types have been shown to contain elevated level of an active polyamine transporter (PAT) for importing exogenous polyamines. In the present study, a bis(benzyl)polyamine analogue (MDL 27695), known to exert antiproliferative activity, has been used as a template where to inserte a well-known DNA-intercalator group (aromatic core) to combine the ability to use the polyamine uptake system with the property to intercale and bind tightly the double-stranded DNA. For this purpose two groups of polyamine derivatives (symmetric or non-symmetric) were synthesized: each group includes 9 compounds which differ for the number of C atom (n=2-10) in the lateral chain to verify the best lenght of the amino-alkyl chain. All derivatives were tested for antiproliferative activity in human breast cancer (SKBR-3) and leukemia (CEM) in vitro in a range of concentrations beetween 0.1 and 10 μM. The MTT assay was used to determine growth inhibition after up 72 h of treatment. Results indicate that the symmetric derivatives are more effective than the corresponding non-symmetric ones in both cell lines. All the symmetric compounds cause a significant dose- and time-dependent growth inhibition in the range of concentration tested. The compound with n=3 emerges as the most potent among the symmetric derivatives, with an IC50 (72h) of 0.35 and 0.17 μM in leukemic and breast cancer cells respectively. The present preliminary results document that some of these polyamine derivatives are more active than polyamine DNA-Intercalator conjugates against human leukemia or than oxa-polyamines derivatives against breast cancer. The pharmacokinetics and pharmacodynamics of the active compounds are now under study

Distinct biological responses of metastatic castration resistant prostate cancer cells upon exposure to G-quadruplex interacting naphthalenediimide derivatives

Small molecules able to bind non-canonical G-quadruplex DNA structures (G4) have been recently tested as novel potential agents for the treatment of prostate cancer thanks to their repression of aberrant androgen receptor gene. However, metastatic castration-resistant prostate cancer (mCRPC), a letal form of prostate cancer, is still incurable. Here we tested two naphthalenediimide derivatives, previously reported as multitarget agents, on a couple of relevant mCRPC cell models (DU145 and PC-3). We showed that these compounds interfere with the RAS/MEK/ERK and PI3K/AKT pathways. Interestingly, both these two biological processes depend upon Epidermal Growth Factor Receptor (EGFR) activation. By means of biological and analytical tools we showed that our compounds are efficient inducers of the structural transition of the EGFR promoter towards a G-quadruplex conformation, ultimately leading to a reduction of the receptor production. The overall result is an interesting cytotoxic profile for these two derivatives. Thanks to their activity at different steps, these compounds can open the way to novel therapeutic approaches for mCRPC that could contribute to escape resistance to selective treatments

PROTAC-Induced Glycogen Synthase Kinase 3β Degradation as a Potential Therapeutic Strategy for Alzheimer’s Disease

Glycogen synthase kinase 3 ss (GSK-3 ss) is a serine/ threonine kinase and an attractive therapeutic target for Alzheimer's disease. Based on proteolysis-targeting chimera (PROTAC) technology, a small set of novel GSK-3 ss degraders was designed and synthesized by linking two different GSK-3 ss inhibitors, SB-216763 and tideglusib, to pomalidomide, as E3 recruiting element, through linkers of different lengths. Compound 1 emerged as the most effective PROTAC being nontoxic up to 20 mu M to neuronal cells and already able to degrade GSK-3 ss starting from 0.5 mu M in a dose- dependent manner. PROTAC 1 significantly reduced the neurotoxicity induced by A ss 25- 35 peptide and CuSO4 in SH-SY5Y cells in a dose-dependent manner. Based on its encouraging features, PROTAC 1 may serve as a starting point to develop new GSK-3 ss degraders as potential therapeutic agents. KEYWORDS: proteolysis targeting chimeras, glycogen synthase kinase 3 ss, Alzheimer's disease, chemical knockdown, protein degradatio

Progress in acetylcholinesterase inhibitors for Alzheimer's disease: an update

A review. To date, the pharmacotherapy of Alzheimer's disease (AD) has been based on acetylcholinesterase inhibitors (AChEIs), and more recently on an N-methyl-D-aspartate receptor antagonist. By increasing acetylcholine concn. in the brain, AChEIs slow behavioral and functional impairments, improving cognitive function. The review provides an update on novel analogs of approved AChEIs, their combination with other anti-AD agents, natural AChEIs, and modern multitarget-directed ligands (MTDLs) able to hit different biol. targets. The authors reviewed patents filed during 2005-2007 dealing with new AChEIs and their potential application for AD treatment. The authors point out new chem. structures and scaffolds for designing new AD therapeutic agents as well as new combinations or MTDLs. Compared to the limited no. of novel com. available AChEI analogs, many new natural compds. were patented for AD treatment. These might represent a starting point for the rational design of new MTDLs

Novel polyamine analogues: from substrates towards potential inhibitors of monoamine oxidases.

Polyamine analogues are extensively researched investigated for their potential pharmacological applications as anticancer (Casero et al. 2009) and antimalarial agents (Verlinden et al., 2011), as well as in the development of multitarget-directed ligands (MTDLs) for novel therapies in neurodegenerative and other multi-factorial diseases (Melchiorre et al. 2010). In the MTLDs field, the polyamine backbone behaves as a \u201cuniversal template\u201d, able to bind different biological targets with an affinity and selectivity that may be fine-tuned by inserting appropriate substituents on nitrogen atoms and by varying the polymethylene chain lengths (Minarini et al. 2010). In the search of new MTDLs to combat neurodegenerative diseases, we designed new polyamines with the aim to inhibit additional target involved in these pathologies. Among these, human monoamine oxidases (MAOs) are emerging potential targets (Bortolato et al., 2008, Boomsma et al., 2003), since may contribute to the oxidative damage involved not only in neurodegenerative diseases but also in other ones and other pathologies, such as diabetes, cardiovascular and inflammatory disorders (Cohen and Tong 2010). Monoamine oxidases (MAO A and MAO B) and Semicarbazide-Sensitive Amine Oxidase/Vascular Adhesion Protein-1 (SSAO/VAP-1) catalyze the oxidative deamination of biogenic amines to produce aldehyde, hydrogen peroxide and ammonia. The starting points of our study were the negligible enzyme activities of MAOs and SSAO/VAP-1 on spermine and our previous results on Bis-BZA-DIADO, which we found able to inhibit both MAO B and SSAO/VAP-1 (Bonaiuto et al., 2012). Eight novel synthetic polyamines were tested as substrates and inhibitors on SSAO/VAP-1 and MAOs. From the kinetic studies carried out so far, we found novel substrates of SSAO/VAP-1 and two novel types of specific MAOs inhibitors: BD28, more selective for MAO B (Ki= 32 \uf06dM) and NT27 (Ki = 15 \uf06dM). Interestingly, NT 27 acts as an irreversible inhibitor of MAO A while, on MAO B, it behaves as a mixed and reversible inhibitor. Further studies are in progress to understand elucidate the binding mode of these compounds to MAOs, in such a way, to modify their structure in order to improve their affinity and selectivity for future application as MTLDs in neurodegenerative diseases

The predictive capacity of the high resolution weather research and forecasting model: a year-long verification over Italy

Numerical models are operationally used for weather forecasting activities to reduce the risks of several hydro-meteorological disasters. The overarching goal of this work is to evaluate the Weather Research and Forecasting (WRF) model predictive capabilities over the Italian national territory in the year 2018, in two specific cloud resolving configurations. The validation is carried out with a fuzzy logic approach, by comparing the precipitation predicted by the WRF model, and the precipitation observed by the national network. The fuzzy logic technique, by considering different intensity thresholds, allows to identify the reliable spatial scales of the forecasts. The same approach is applied to evaluate the performances of COSMO-2I model, a state-of-the-art numerical model configuration used for operational activities. For the entire year, except for summer, the model predictive capabilities are high, with useful forecasts for structures of medium intensities down to O(10 km) length scales. In summer the skills decrease mainly because of localization errors. The work aims to provide a robust evaluation of the forecast performances of another convection permitting operational meteorological models currently available in Italy