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The HIV-1 integrase (IN) plays a critical role in the viral lifecycle by integrating the viral DNA into the host chromosome. The catalytic function of IN has been exploited as a target, with five drugs acting as active site binders (IN strand transfer inhibitors, INSTIs). However, IN mutations conferring low-level resistance to INSTIs have been reported. Therefore, new IN inhibitors with different mechanisms of action are needed. The allosteric inhibition of IN, exerted by allosteric IN inhibitors (ALLINIs), is gaining interest. ALLINIs inhibit IN by inducing aberrant IN multimerization with different mechanisms. Furthermore, recent discoveries unveiled that IN has an under-studied yet equally vital second function. This involves IN binding to the RNA genome in virions, necessary for proper virion maturation. In this work, we describe a series of quinolinonyl derivatives as inhibitors of both the IN catalytic functions and IN-RNA interactions, which impair both early and late steps of viral replication., Competing Interests: The authors declare no competing financial interest., (© 2024 American Chemical Society.)

It has been more than four years since the first report of SARS-CoV-2, and humankind has experienced a pandemic with an unprecedented impact. Moreover, the new variants have made the situation even worse. Among viral enzymes, the SARS-CoV-2 main protease (M pro ) has been deemed a promising drug target vs. COVID-19. Indeed, M pro is a pivotal enzyme for viral replication, and it is highly conserved within coronaviruses. It showed a high extent of conservation of the protease residues essential to the enzymatic activity, emphasizing its potential as a drug target to develop wide-spectrum antiviral agents effective not only vs. SARS-CoV-2 variants but also against other coronaviruses. Even though the FDA-approved drug nirmatrelvir, a M pro inhibitor, has boosted the antiviral therapy for the treatment of COVID-19, the drug shows several drawbacks that hinder its clinical application. Herein, we report the synthesis of new thiazolidine-4-one derivatives endowed with inhibitory potencies in the micromolar range against SARS-CoV-2 M pro . In silico studies shed light on the key structural requirements responsible for binding to highly conserved enzymatic residues, showing that the thiazolidinone core acts as a mimetic of the Gln amino acid of the natural substrate and the central role of the nitro-substituted aromatic portion in establishing π-π stacking interactions with the catalytic His-41 residue.

Developing drugs for brain infection by Naegleria fowleri is an unmet medical need. We used a combination of cheminformatics, target-, and phenotypic-based drug discovery methods to identify inhibitors that target an essential N. fowleri enzyme, sterol 14-demethylase (NfCYP51). A total of 124 compounds preselected in silico were tested against N. fowleri . Nine primary hits with EC 50 ≤ 10 μM were phenotypically identified. Cocrystallization with NfCYP51 focused attention on one primary hit, miconazole-like compound 2a . The S -enantiomer of 2a produced a 1.74 Å cocrystal structure. A set of analogues was then synthesized and evaluated to confirm the superiority of the S -configuration over the R -configuration and the advantage of an ether linkage over an ester linkage. The two compounds, S - 8b and S - 9b , had an improved EC 50 and K D compared to 2a . Importantly, both were readily taken up into the brain. The brain-to-plasma distribution coefficient of S - 9b was 1.02 ± 0.12, suggesting further evaluation as a lead for primary amoebic meningoencephalitis.

For RNA viruses, RNA helicases have long been recognized to play critical roles during virus replication cycles, facilitating proper folding and replication of viral RNAs, therefore representing an ideal target for drug discovery. SARS-CoV-2 helicase, the non-structural protein 13 (nsp13) is a highly conserved protein among all known coronaviruses, and, at the moment, is one of the most explored viral targets to identify new possible antiviral agents. In the present study, we present six diketo acids (DKAs) as nsp13 inhibitors able to block both SARS-CoV-2 nsp13 enzymatic functions. Among them four compounds were able to inhibit viral replication in the low micromolar range, being active also on other human coronaviruses such as HCoV229E and MERS CoV. The experimental investigation of the binding mode revealed ATP-non-competitive kinetics of inhibition, not affected by substrate-displacement effect, suggesting an allosteric binding mode that was further supported by molecular modelling calculations predicting the binding into an allosteric conserved site located in the RecA2 domain., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Heparanase (HPSE) is an endo-β-glucuronidase that cleaves heparan sulfate side chains, leading to the disassembly of the extracellular matrix, facilitating cell invasion and metastasis dissemination. In this research, we investigated the role of a new HPSE inhibitor, RDS 3337, in the regulation of the autophagic process and the balance between apoptosis and autophagy in U87 glioblastoma cells., Methods: After treatment with RDS 3337, cell lysates were analyzed for autophagy and apoptosis-related proteins by Western blot., Results: We observed, firstly, that LC3II expression increased in U87 cells incubated with RDS 3337, together with a significant increase of p62/SQSTM1 levels, indicating that RDS 3337 could act through the inhibition of autophagic-lysosomal flux of LC3-II, thereby leading to accumulation of lipidated LC3-II form. Conversely, the suppression of autophagic flux could activate apoptosis mechanisms, as revealed by the activation of caspase 3, the increased level of cleaved Parp1, and DNA fragmentation., Conclusions: These findings support the notion that HPSE promotes autophagy, providing evidence that RDS 3337 blocks autophagic flux. It indicates a role for HPSE inhibitors in the balance between apoptosis and autophagy in U87 human glioblastoma cells, suggesting a potential role for this new class of compounds in the control of tumor growth progression.

Plants have been known since ancient times for their healing properties, being used as preparations against human diseases of different etiologies. More recently, natural products have been studied and characterized, isolating the phytochemicals responsible for their bioactivity. Most certainly, there are currently numerous active compounds extracted from plants and used as drugs, dietary supplements, or sources of bioactive molecules that are useful in modern drug discovery. Furthermore, phytotherapeutics can modulate the clinical effects of co-administered conventional drugs. In the last few decades, the interest has increased even more in studying the positive synergistic effects between plant-derived bioactives and conventional drugs. Indeed, synergism is a process where multiple compounds act together to exert a merged effect that is greater than that of each of them summed together. The synergistic effects between phytotherapeutics and conventional drugs have been described in different therapeutic areas, and many drugs are based on synergistic interactions with plant derivatives. Among them, caffeine has shown positive synergistic effects with different conventional drugs. Indeed, in addition to their multiple pharmacological activities, a growing body of evidence highlights the synergistic effects of caffeine with different conventional drugs in various therapeutic fields. This review aims to provide an overview of the synergistic therapeutic effects of caffeine and conventional drugs, summarizing the progress reported to date.

Solid tumors are active tissues containing hypoxic regions and producing metabolic acids. By decreasing pH, cancer cells create a hostile environment for surrounding host cells and foster tumor growth and progression. By governing acid/base regulation, carbonic anhydrases (CAs) are involved in several physiological/pathological processes, including tumors. Indeed, CAs are clinically relevant in cancer therapy as among the fifteen human isoforms, two of them, namely CA IX (overexpressed in solid tumors and associated with increased metastasis and poor prognosis) and CA XII (overexpressed in some tumors) are involved in tumorigenesis. Targeting these two isoforms is considered as a pertinent approach to develop new cancer therapeutics. Several CA inhibitors (CAIs) have been described, even though they are unselective inhibitors of different isoforms. Thus, efforts are needed to find new selective CAIs. In this work, we described new diketo acid derivatives as CAIs, with the best acting compounds 1c and 5 as nanomolar inhibitors of CA IX and XII, being also two orders of magnitude selective over CAs I and II. Molecular modeling studies showed the different binding poses of the best acting CAIs within CA II and IX, highlighting the key structural features that could confer the ability to establish specific interactions within the enzymes. In different tumor cell lines overexpressing CA IX and XII, the tested compounds showed antiproliferative activity already at 24 h treatment, with no effects on somatic not transformed cells.

Background: As a result of the paucity of treatment, Leishmaniasis continues to provoke about 60,000 deaths every year worldwide. New molecules are needed, and drug discovery research is oriented toward targeting proteins crucial for parasite survival. Among them, trypanothione reductase (TR) is of remarkable interest owing to its vital role in Leishmania species protozoan parasite life. Our previously identified compound 1 is a novel chemotype endowed with a unique mode of TR inhibition thanks to its binding to a formerly unknown but druggable site at the entrance of the NADPH binding cavity, absent in human glutathione reductase (hGR)., Methods: We designed and synthesized new 3-amino-1-arylpropan-1-one derivatives structurally related to compound 1 and evaluated their potential inhibition activity on TR from Leishmania infantum (LiTR). Cluster docking was performed to assess the binding poses of the compounds., Results: The newly synthesized compounds were screened at a concentration of 100 μM in in vitro assays and all of them proved to be active with residual activity percentages lower than 75%., Conclusions: Compounds 2a and 2b were the most potent inhibitors found, suggesting that an additional aromatic ring might be promising for enzymatic inhibition. Further structure-activity relationships are needed to optimize our compounds activity.

Histone acetyltransferases (HATs) are involved in the epigenetic positive control of gene expression in eukaryotes. CREB-binding proteins (CBP)/p300, a subfamily of highly conserved HATs, have been shown to function as acetylases on both histones and non-histone proteins. In the model plant Arabidopsis thaliana among the five CBP/p300 HATs, HAC1, HAC5 and HAC12 have been shown to be involved in the ethylene signaling pathway. In addition, HAC1 and HAC5 interact and cooperate with the Mediator complex, as in humans. Therefore, it is potentially difficult to discriminate the effect on plant development of the enzymatic activity with respect to their Mediator-related function. Taking advantage of the homology of the human HAC catalytic domain with that of the Arabidopsis, we set-up a phenotypic assay based on the hypocotyl length of Arabidopsis dark-grown seedlings to evaluate the effects of a compound previously described as human p300/CBP inhibitor, and to screen previously described cinnamoyl derivatives as well as newly synthesized analogues. We selected the most effective compounds, and we demonstrated their efficacy at phenotypic and molecular level. The in vitro inhibition of the enzymatic activity proved the specificity of the inhibitor on the catalytic domain of HAC1, thus substantiating this strategy as a useful tool in plant epigenetic studies.

Influenza viruses are transmitted from human to human via airborne droplets and can be transferred through contaminated environmental surfaces. Some works have demonstrated the efficacy of essential oils (EOs) as antimicrobial and antiviral agents, but most of them examined the liquid phases, which are generally toxic for oral applications. In our study, we describe the antiviral activity of Citrus bergamia , Melaleuca alternifolia , Illicium verum and Eucalyptus globulus vapor EOs against influenza virus type A. In the vapor phase, C. bergamia and M. alternifolia strongly reduced viral cytopathic effect without exerting any cytotoxicity. The E. globulus vapor EO reduced viral infection by 78% with no cytotoxicity, while I. verum was not effective. Furthermore, we characterized the EOs and their vapor phase by the head-space gas chromatography-mass spectrometry technique, observing that the major component found in each liquid EO is the same one of the corresponding vapor phases, with the exception of M. alternifolia . To deepen the mechanism of action, the morphological integrity of virus particles was checked by negative staining transmission electron microscopy, showing that they interfere with the lipid bilayer of the viral envelope, leading to the decomposition of membranes. We speculated that the most abundant components of the vapor EOs might directly interfere with influenza virus envelope structures or mask viral structures important for early steps of viral infection.

Growing attention to environmental protection leads food industries to adopt a model of "circular economy" applying safe and sustainable technologies to recover, recycle and valorize by-products. Therefore, by-products become raw material for other industries. Tomato processing industry produces significant amounts of by-products, consisting of skins and seeds. Tomato skin is very rich in lycopene, and from its seeds, high nutritional oil can be extracted. Alternative use of the two fractions not only could cut disposal costs but also allow one to extract bioactive compounds and an oil with a high nutritional value. This review focused on the recent advance in extraction of lycopene, whose beneficial effects on health are widely recognized.

Novel anti-HIV agents are still needed to overcome resistance issues, in particular inhibitors acting against novel viral targets. The ribonuclease H (RNase H) function of the reverse transcriptase (RT) represents a validated and promising target, and no inhibitor has reached the clinical pipeline yet. Here, we present rationally designed non-diketo acid selective RNase H inhibitors (RHIs) based on the quinolinone scaffold starting from former dual integrase (IN)/RNase H quinolinonyl diketo acids. Several derivatives were synthesized and tested against RNase H and viral replication and found active at micromolar concentrations. Docking studies within the RNase H catalytic site, coupled with site-directed mutagenesis, and Mg 2+ titration experiments demonstrated that our compounds coordinate the Mg 2+ cofactor and interact with amino acids of the RNase H domain that are highly conserved among naïve and treatment-experienced patients. In general, the new inhibitors influenced also the polymerase activity of RT but were selective against RNase H vs the IN enzyme.

Nocodazole is an antineoplastic agent that exerts its effects by depolymerizing microtubules. Herein we report a structural analog of nocodazole, a (1 H -pyrrol-1-yl)methyl-1 H -benzoimidazole carbamate ester derivative, named RDS 60. We evaluated the antineoplastic properties of RDS 60 in two human head and neck squamous cell carcinoma (HNSCC) cell lines and we found that this compound significantly inhibited replication of both HNSCC cell lines without inducing any important cytotoxic effect on human dermal fibroblasts and human keratinocytes. The treatment of HNSCC cell lines with 1 μM RDS 60 for 24 h stopped development of normal bipolar mitotic spindles and, at the same time, blocked the cell cycle in G2/M phase together with cytoplasmic accumulation of cyclin B1. Consequently, treatment with 2 μM RDS 60 for 24 h induced the activation of apoptosis in both HNSCC cell lines. Additionally, RDS 60 was able to reverse the epithelial-mesenchymal transition and to inhibit cell migration and extracellular matrix infiltration of both HNSCC cell lines. The reported results demonstrate that this compound has a potent effect in blocking cell cycle, inducing apoptosis and inhibiting cell motility and stromal invasion of HNSCC cell lines. Therefore, the ability of RDS 60 to attenuate the malignancy of tumor cells suggests its potential role as an interesting and powerful tool for new approaches in treating HNSCC.

Plant-based systems continue to play a pivotal role in healthcare, and their use has been extensively documented. Asphodelus L. is a genus comprising various herbaceous species, known by the trivial name Asphodelus. These plants have been known since antiquity for both food and therapeutic uses, especially for treating several diseases associated with inflammatory and infectious skin disorders. Phytochemical studies revealed the presence of different constituents, mainly anthraquinones, triterpenoids, phenolic acids, and flavonoids. Although extensive literature has been published on these constituents, a paucity of information has been reported regarding the carbohydrate composition, such as fructans and fructan-like derivatives. The extraction of water-soluble neutral polysaccharides is commonly performed using water extraction, at times assisted by microwaves and ultrasounds. Herein, we reported the investigation of the alkaline extraction of root-tubers of Asphodelus ramosus L., analyzing the water-soluble polysaccharides obtained by precipitation from the alkaline extract and its subsequent purification by chromatography. A polysaccharide was isolated by alkaline extraction; the HPTLC study to determine its composition showed fructose as the main monosaccharide. FT-IR analysis showed the presence of an inulin-type structure, and NMR analyses allowed us to conclude that A. ramosus roots contain polysaccharide with an inulin-type fructooligosaccharide with a degree of polymerization of 7-8.

The resinous exudate produced by Commiphora myrrha (Nees) Engl. is commonly known as true myrrh and has been used since antiquity for several medicinal applications. Hundreds of metabolites have been identified in the volatile component of myrrh so far, mainly sesquiterpenes. Although several efforts have been devoted to identifying these sesquiterpenes, the phytochemical analyses have been performed by gas-chromatography/mass spectrometry (GC-MS) where the high temperature employed can promote degradation of the components. In this work, we report the extraction of C. myrrha by supercritical CO 2 , an extraction method known for the mild extraction conditions that allow avoiding undesired chemical reactions during the process. In addition, the analyses of myrrh oil and of its metabolites were performed by HPLC and GC-MS. Moreover, we evaluated the antiviral activity against influenza A virus of the myrrh extracts, that was possible to appreciate after the addition of vitamin E acetate (α-tocopheryl acetate) to the extract. Further, the single main bioactive components of the oil of C. myrrha commercially available were tested. Interestingly, we found that both furanodienone and curzerene affect viral replication by acting on different steps of the virus life cycle.

Background: Anticancer drug resistance is a challenging phenomenon of growing concern which arises from alteration in drug targets. Despite the fast speed of new chemotherapeutic agent design, the increasing prevalence of this phenomenon requires further research and treatment development. Recently, we reported a new aminopyrimidine compound-namely RDS 344-as a potential innovative anticancer agent., Methods: Herein, we report the design, synthesis, and anti-proliferative activity of new aminopyrimidine derivatives structurally related to RDS 3442 obtained by carrying out substitutions at position 6 of the pyrimidine core and/or on the 2-aniline ring of our hit. The ability to inhibit cell proliferation was evaluated on different types of tumors, glioblastoma, triple-negative breast cancer, oral squamous cell carcinomas and colon cancer plus on human dermal fibroblasts chosen as control of normal cells., Results: The most interesting compound was the N -benzyl counterpart of RDS 3442, namely 2a , that induced a significant decrease in cell viability in all the tested tumor cell lines, with EC 50 s ranging from 4 and 8 μM, 4-13 times more active of hit., Conclusions: These data suggest a potential role for this class of molecules as promising tool for new approaches in treating cancers of different histotype.

The prognostic value of induction of ventricular tachycardia (VT) by programmed electrical stimulation (PES) was analyzed in 123 patients: 64 (Group I) with spontaneous recurrent VT and 59 (Group II) without a history of serious arrhythmias. Thirty-three patients with spontaneous VT underwent coronary and left ventricular angiography to compare electrical instability with the presence of ventricular disfunction and/or the extent of coronary artery disease (CAD). PES reproducibly induced VT in 49/64 patients with spontaneous VT (sensitivity = 77%) and in 6/59 patients without VT (specificity = 90%). Twenty-two patients (66%) had ventricular disfunction defined by an ejection fraction of less than or equal to 40% or regional wall motion abnormalities. Only 4 patients (33%) had proximal 3-vessel CAD. The mean follow-up period was 16 +/- 12 months. Eight of Group I patients died suddenly and 24 had recurrent symptomatic VT. Three of Group I patients died (1 cardiac failure, 2 non-cardiac deaths), all the survivors were free of serious arrhythmias. In Group I patients mortality was correlated with: recent anterior myocardial infarction, inducible sustained VT with PES, ejection fraction less than or equal to 0.40, ventricular ipoasynergy and or at least one coronary stenosis greater than or equal to 70%. This study suggests that inducible VT is a marker of the risk of sudden death. Electrical instability may occur independent from the etiology of cardiopathy, ventricular disfunction and extent of CAD, but these parameters are correlated to global and sudden mortality in the group of patients with spontaneous VT.

Recently, polyurethane cardiac pacing leads have been under discussion because of some failures, probably due to modification of surface insulating properties. In order to verify the reliability of polyurethane versus silicone rubber as coating material, the authors, starting from previous clinical research, have carried out a study of electrical insulation related to implant time. At the same time the outer and inner lead surfaces have been submitted to scanning electron microscope (SEM) analysis. The results show, for the polyurethane leads, a significant increase in the leakage or currents in explanted samples, and a significant degradation (cracking) of the outer surfaces.

Little information is available regarding cardiac automatism and conduction disturbances in patients affected by congestive (CCM) or hypertrophic (HCM) cardiomyopathies. For this reason 29 patients with HCM (10 cases) and CCM (19 cases) and disturbances of sinus node automaticity or AV conduction underwent an electrophysiologic study. Eight patients affected by HCM were also submitted to cardiac catheterization. Sinus node function was normal in each of the HCM patients, and impaired in 6 of the 19 CCM patients. The intra-atrial conduction was prolonged in only one CCM case. One HCM and 2 CCM patients showed an impaired intranodal AV conduction. Thirteen patients (44%) showed a prolonged HV interval (3 HCM and 10 CCM patients). No calcific deposits on the aortic valve were discovered by X ray stratigraphic examination in any of the patients. In 6 cases a progression of the conduction disturbances was observed. Ventricular pre-excitation was present in 4 patients (13%).

The Authors have re-examined their case histories of 1503 patients who have had 2459 pacemakers implanted and who have undergone check-ups as outpatients. All the complications which have arisen from 1967 to the present have been taken into consideration. The total number of complications has been found in 355 patients with 14% of the total number of pacemakers and they have been subdivided into 3 groups: 1st group: complications arising during the stay in hospital (110); 2nd group: complications arising after discharge from hospital and discovered by the patient (239); 3rd group: complications found casually during outpatients' check-ups (6). Of the complications found after discharge, 97% belong to the second group and only 3% to the third group. 657 substituted pacemakers have also been taken into consideration with the purpose of finding out the parameters which showed up as the battery was running down. Out of 145 pacemakers substituted because of flat batteries, 130 (90%) have shown brusque variations in the frequency of stimulation, while only 15 (10%) have shown variations in other parameters (width, length of impulse, etc). The Authors therefore retain that a periodic outpatients' check-up of the pacemakers is of little use as regards the patients' safety and the complete utilization of the device, while they advise that the patient be educated so as to be able to carry out his own daily control of the pacemaker.