In silico Prediction of Pranlukast as a Stabilizer of PD-L1 Homodimers.

INTRODUCTION: Tumors can be targeted by modulating the immune response of the patient. Programmed cell death protein 1 (PD-1) and programmed cell death ligand 1 (PD-L1) are critical immune checkpoints in cancer biology. The efficacy of certain cancer immunotherapies has been achieved by targeting these molecules using monoclonal antibodies. METHOD: Small-molecule drugs have also been developed as inhibitors of the PD-1/PD-L1 axis, with a mechanism of action that is distinct from that of antibodies: they induce the formation of PD-L1 homodimers, causing their stabilization, internalization, and subsequent degradation. Drug repurposing is a strategy in which new uses are sought after for approved drugs, expediting their clinical translation based on updated findings. In this study, we generated a pharmacophore model that was based on reported small molecules that targeted PD-L1 and used it to identify potential PD-L1 inhibitors among FDA-approved drugs. RESULTS: We identified 12 pharmacophore-matching compounds, but only 4 reproduced the binding mode of the reference inhibitors in docking experiments. Further characterization by molecular dynamics showed that pranlukast, an antagonist of leukotriene receptors that is used to treat asthma, generated stable and energyfavorable interactions with PD-L1 homodimers and induced homodimerization of recombinant PD-L1. CONCLUSION: Our results suggest that pranlukast inhibits the PD-1/PD-L1 axis, meriting its repurposing as an antitumor drug.

In silico comparative analysis of cestode and human NPC1 provides insights for ezetimibe repurposing to visceral cestodiases treatment.

Visceral cestodiases, like cysticercoses and echinococcoses, are caused by cystic larvae from parasites of the Cestoda class and are endemic or hyperendemic in many areas of the world. Current therapeutic approaches for these diseases are complex and present limitations and risks. Therefore, new safer and more effective treatments are urgently needed. The Niemann-Pick C1 (NPC1) protein is a cholesterol transporter that, based on genomic data, would be the solely responsible for cholesterol uptake in cestodes. Considering that human NPC1L1 is a known target of ezetimibe, used in the treatment of hypercholesterolemia, it has the potential for repurposing for the treatment of visceral cestodiases. Here, phylogenetic, selective pressure and structural in silico analyses were carried out to assess NPC1 evolutive and structural conservation, especially between cestode and human orthologs. Two NPC1 orthologs were identified in cestode species (NPC1A and NPC1B), which likely underwent functional divergence, leading to the loss of cholesterol transport capacity in NPC1A. Comparative interaction analyses performed by molecular docking of ezetimibe with human NPC1L1 and cestode NPC1B pointed out to similarities that consolidate the idea of cestode NPC1B as a target for the repurposing of ezetimibe as a drug for the treatment of visceral cestodiases.

Structural Characterization of Heat Shock Protein 90ß and Molecular Interactions with Geldanamycin and Ritonavir: A Computational Study.

Drug repositioning is an important therapeutic strategy for treating breast cancer. Hsp90ß chaperone is an attractive target for inhibiting cell progression. Its structure has a disordered and flexible linker region between the N-terminal and central domains. Geldanamycin was the first Hsp90ß inhibitor to interact specifically at the N-terminal site. Owing to the toxicity of geldanamycin, we investigated the repositioning of ritonavir as an Hsp90ß inhibitor, taking advantage of its proven efficacy against cancer. In this study, we used molecular modeling techniques to analyze the contribution of the Hsp90ß linker region to the flexibility and interaction between the ligands geldanamycin, ritonavir, and Hsp90ß. Our findings indicate that the linker region is responsible for the fluctuation and overall protein motion without disturbing the interaction between the inhibitors and the N-terminus. We also found that ritonavir established similar interactions with the substrate ATP triphosphate, filling the same pharmacophore zone.

Milteforan, a promising veterinary commercial product against feline sporotrichosis.

Sporotrichosis, the cutaneous mycosis most commonly reported in Latin America, is caused by the Sporothrix clinical clade species, including Sporothrix brasiliensis and Sporothrix schenckii sensu stricto. Due to its zoonotic transmission in Brazil, S. brasiliensis represents a significant health threat to humans and domestic animals. Itraconazole, terbinafine, and amphotericin B are the most used antifungals for treating sporotrichosis. However, many strains of S. brasiliensis and S. schenckii have shown resistance to these agents, highlighting the importance of finding new therapeutic options. Here, we demonstrate that milteforan, a commercial veterinary product against dog leishmaniasis, whose active principle is miltefosine, is a possible therapeutic alternative for the treatment of sporotrichosis, as observed by its fungicidal activity in vitro against different strains of S. brasiliensis and S. schenckii. Fluorescent miltefosine localizes to the Sporothrix cell membrane and mitochondria and causes cell death through increased permeabilization. Milteforan decreases S. brasiliensis fungal burden in A549 pulmonary cells and bone marrow-derived macrophages and also has an immunomodulatory effect by decreasing TNF-α, IL-6, and IL-10 production. Our results suggest milteforan as a possible alternative to treat feline sporotrichosis. IMPORTANCE: Sporotrichosis is an endemic disease in Latin America caused by different species of Sporothrix. This fungus can infect domestic animals, mainly cats and eventually dogs, as well as humans. Few drugs are available to treat this disease, such as itraconazole, terbinafine, and amphotericin B, but resistance to these agents has risen in the last few years. Alternative new therapeutic options to treat sporotrichosis are essential. Here, we propose milteforan, a commercial veterinary product against dog leishmaniasis, whose active principle is miltefosine, as a possible therapeutic alternative for treating sporotrichosis. Milteforan decreases S. brasiliensis fungal burden in human and mouse cells and has an immunomodulatory effect by decreasing several cytokine production.

From Proteome to Potential Drugs: Integration of Subtractive Proteomics and Ensemble Docking for Drug Repurposing against Pseudomonas aeruginosa RND Superfamily Proteins.

Pseudomonas aeruginosa (P. aeruginosa) poses a significant threat as a nosocomial pathogen due to its robust resistance mechanisms and virulence factors. This study integrates subtractive proteomics and ensemble docking to identify and characterize essential proteins in P. aeruginosa, aiming to discover therapeutic targets and repurpose commercial existing drugs. Using subtractive proteomics, we refined the dataset to discard redundant proteins and minimize potential cross-interactions with human proteins and the microbiome proteins. We identified 12 key proteins, including a histidine kinase and members of the RND efflux pump family, known for their roles in antibiotic resistance, virulence, and antigenicity. Predictive modeling of the three-dimensional structures of these RND proteins and subsequent molecular ensemble-docking simulations led to the identification of MK-3207, R-428, and Suramin as promising inhibitor candidates. These compounds demonstrated high binding affinities and effective inhibition across multiple metrics. Further refinement using non-covalent interaction index methods provided deeper insights into the electronic effects in protein-ligand interactions, with Suramin exhibiting superior binding energies, suggesting its broad-spectrum inhibitory potential. Our findings confirm the critical role of RND efflux pumps in antibiotic resistance and suggest that MK-3207, R-428, and Suramin could be effectively repurposed to target these proteins. This approach highlights the potential of drug repurposing as a viable strategy to combat P. aeruginosa infections.

Analysis of VEGFR-2 and PDGFR-ß expression in canine splenic hemangiosarcoma to identify drug repositioning candidates.

Splenic tumors are very common in dogs, and canine hemangiosarcoma (HSA) is one of the most important malignant splenic tumors. Surgery followed by chemotherapy (anthracycline-based protocols) is recommended for treating canine HSA; however, patients still do not achieve long-term survival. Therefore, this research aimed to assess vascular endothelial growth factor receptor-2 (VEGFR-2) and platelet-derived growth factor receptor-ß (PDGFR-ß) gene expression in formalin-fixed tissues, evaluate the quality of mRNA for quantitative polymerase chain reaction (qPCR) analysis and identify drug repositioning candidates based on VEGFR-2 and PDGFR-ß. qPCR analysis identified the relative expression of heterogeneous VEGFR-2 and PDGFR-ß, with samples showing no transcripts or very low expression and those with higher relative quantification for both genes. We then used immunohistochemistry to correlate the relative quantification of VEGFR-2 and PDGFR-ß transcripts with respective higher protein expression to validate our results. In the next step, we evaluated drug repositioning candidates and identified small molecule inhibitors (i.e. sorafenib) and natural compounds (curcumin and resveratrol) with the ability to block VEGFR-2 and PDGFR-ß genes. Overall, our results indicated that VEGFR-2 and PDGFR-ß expression is highly variable among canine HSA samples and different drugs can block the expression of both genes. Therefore, a personalized approach could be useful for selecting anti-VEGFR-2 and PDGFR-ß therapies and both genes are potential candidates for future oncological panels.

Os tumores esplênicos são muito comuns em cães, e o hemangiosarcoma (HSA) é um dos tumores esplênicos malignos mais importantes em cães. A cirurgia seguida de quimioterapia (protocolos baseados em antraciclinas) é a abordagem terapêutica mais recomendada para o tratamento da HSA canino; no entanto, os pacientes ainda não alcançam longa sobrevida após tratamento. Portanto, esta pesquisa teve como objetivo avaliar a expressão do receptor do fator de crescimento endotelial vascular-2 (VEGFR-2) e do receptor do fator de crescimento derivado de plaquetas-ß (PDGFR-ß) em tecidos fixados em formalina e identificar candidatos ao reposicionamento de medicamentos baseado na expressão desses genes. A análise qPCR identificou a expressão relativa heterogênea de VEGFR-2 e PDGFR-ß, com amostras sem transcritos ou com expressão muito baixa ou amostras com alta quantificação relativa para ambos os genes. Em seguida, foi realizada o exame imuno-histoquímico para correlacionar a quantificação relativa dos transcritos de VEGFR-2 e PDGFR-ß com a respectiva maior expressão proteica para validar nossos resultados. Na próxima etapa, avaliamos candidatos ao reposicionamento de medicamentos e identificamos inibidores de moléculas pequenas (ou seja, sorafenibe) e compostos naturais (curcumina e resveratrol) com capacidade de bloquear os genes VEGFR-2 e PDGFR-ß. No geral, nossos resultados indicaram que a expressão de VEGFR-2 e PDGFR-ß é altamente variável entre amostras caninas de HSA e diferentes drogas podem bloquear a expressão de ambos os genes. Portanto, uma abordagem personalizada poderia ser útil para selecionar terapias anti-VEGFR-2 e PDGFR-ß e ambos os genes são potenciais candidatos para futuros painéis oncológicos.

Celecoxib exhibits antifungal effect against Paracoccidioides brasiliensis both directly and indirectly by activating neutrophil responses.

BACKGROUND: Celecoxib, an anti-inflammatory drug, combined therapies using antimicrobials and immune modulator drugs are being studied. OBJECTIVE: To assess whether Celecoxib has direct in vitro antifungal effect against the Paracoccidioides brasiliensis, the causative agent of Paracoccidioidomycosis-(PCM) and also if it improves the in vivo activity of neutrophils-(PMN) in an experimental murine subcutaneous-(air pouch) model of the disease. METHODS: The antifungal activity of Celecoxib(6 mg/mL) on P. brasiliensis-(Pb18) was evaluated using the microdilution technique. Splenocytes co-cultured with Pb18 and treated with Celecoxib(6 mg/mL) were co-cultured for 24, 48 and 72-hours. Swiss mice were inoculated with Pb18 and treated with Celecoxib(6 mg/kg) in the subcutaneous air pouch. Neutrophils were collected from the air pouch. Mitochondrial activity, reactive oxygen production, catalase, peroxidase, cytokines and chemokines, nitrogen species, total protein, microbicidal activity of PMNs and viable Pb18 cells numbers were analyzed. RESULTS: Celecoxib had no cytotoxic effect on splenocytes co-cultured with Pb18, but had a marked direct antifungal effect, inhibiting fungal growth both in vitro and in vivo. Celecoxib interaction with immune system cells in the air pouch, it leads to activation of PMNs, as confirmed by several parameters (mitochondrial activity, reactive oxygen species, peroxidase, KC and IL-6 increase, killing constant and phagocytosis). Celecoxib was able to reduce IL-4, IL-10 and IL-12 cytokine production. The number of recovered viable Pb18 decreased dramatically. CONCLUSIONS: This is the first report of the direct antifungal activity of Celecoxib against P. brasiliensis. The use of Celecoxib opens a new possibility for future treatment of PCM.

Drug to genome to drug: a computational large-scale chemogenomics screening for novel drug candidates against sporotrichosis.

Sporotrichosis is recognized as the predominant subcutaneous mycosis in South America, attributed to pathogenic species within the Sporothrix genus. Notably, in Brazil, Sporothrix brasiliensis emerges as the principal species, exhibiting significant sapronotic, zoonotic and enzootic epidemic potential. Consequently, the discovery of novel therapeutic agents for the treatment of sporotrichosis is imperative. The present study is dedicated to the repositioning of pharmaceuticals for sporotrichosis therapy. To achieve this goal, we designed a pipeline with the following steps: (a) compilation and preparation of Sporothrix genome data; (b) identification of orthologous proteins among the species; (c) identification of homologous proteins in publicly available drug-target databases; (d) selection of Sporothrix essential targets using validated genes from Saccharomyces cerevisiae; (e) molecular modeling studies; and (f) experimental validation of selected candidates. Based on this approach, we were able to prioritize eight drugs for in vitro experimental validation. Among the evaluated compounds, everolimus and bifonazole demonstrated minimum inhibitory concentration (MIC) values of 0.5 µg/mL and 4.0 µg/mL, respectively. Subsequently, molecular docking studies suggest that bifonazole and everolimus may target specific proteins within S. brasiliensis- namely, sterol 14-α-demethylase and serine/threonine-protein kinase TOR, respectively. These findings shed light on the potential binding affinities and binding modes of bifonazole and everolimus with their probable targets, providing a preliminary understanding of the antifungal mechanism of action of these compounds. In conclusion, our research advances the understanding of the therapeutic potential of bifonazole and everolimus, supporting their further investigation as antifungal agents for sporotrichosis in prospective hit-to-lead and preclinical investigations.

In silico approaches for drug repurposing in oncology: a scoping review.

Introduction: Cancer refers to a group of diseases characterized by the uncontrolled growth and spread of abnormal cells in the body. Due to its complexity, it has been hard to find an ideal medicine to treat all cancer types, although there is an urgent need for it. However, the cost of developing a new drug is high and time-consuming. In this sense, drug repurposing (DR) can hasten drug discovery by giving existing drugs new disease indications. Many computational methods have been applied to achieve DR, but just a few have succeeded. Therefore, this review aims to show in silico DR approaches and the gap between these strategies and their ultimate application in oncology. Methods: The scoping review was conducted according to the Arksey and O'Malley framework and the Joanna Briggs Institute recommendations. Relevant studies were identified through electronic searching of PubMed/MEDLINE, Embase, Scopus, and Web of Science databases, as well as the grey literature. We included peer-reviewed research articles involving in silico strategies applied to drug repurposing in oncology, published between 1 January 2003, and 31 December 2021. Results: We identified 238 studies for inclusion in the review. Most studies revealed that the United States, India, China, South Korea, and Italy are top publishers. Regarding cancer types, breast cancer, lymphomas and leukemias, lung, colorectal, and prostate cancer are the top investigated. Additionally, most studies solely used computational methods, and just a few assessed more complex scientific models. Lastly, molecular modeling, which includes molecular docking and molecular dynamics simulations, was the most frequently used method, followed by signature-, Machine Learning-, and network-based strategies. Discussion: DR is a trending opportunity but still demands extensive testing to ensure its safety and efficacy for the new indications. Finally, implementing DR can be challenging due to various factors, including lack of quality data, patient populations, cost, intellectual property issues, market considerations, and regulatory requirements. Despite all the hurdles, DR remains an exciting strategy for identifying new treatments for numerous diseases, including cancer types, and giving patients faster access to new medications.

Identification of Orthosteric and Allosteric Pharmacological Chaperones for Mucopolysaccharidosis Type IIIB.

Mucopolysaccharidosis type IIIB (MPS IIIB) is an autosomal inherited disease caused by mutations in gene encoding the lysosomal enzyme N-acetyl-alpha-glucosaminidase (NAGLU). These mutations result in reduced NAGLU activity, preventing it from catalyzing the hydrolysis of the glycosaminoglycan heparan sulfate (HS). There are currently no approved treatments for MPS IIIB. A novel approach in the treatment of lysosomal storage diseases is the use of pharmacological chaperones (PC). In this study, we used a drug repurposing approach to identify and characterize novel potential PCs for NAGLU enzyme. We modeled the interaction of natural and artificial substrates within the active cavity of NAGLU (orthosteric site) and predicted potential allosteric sites. We performed a virtual screening for both the orthosteric and the predicted allosteric site against a curated database of human tested molecules. Considering the binding affinity and predicted blood-brain barrier permeability and gastrointestinal absorption, we selected atovaquone and piperaquine as orthosteric and allosteric PCs. The PCs were evaluated by their capacity to bind NAGLU and the ability to restore the enzymatic activity in human MPS IIIB fibroblasts These results represent novel PCs described for MPS IIIB and demonstrate the potential to develop novel therapeutic alternatives for this and other protein deficiency diseases.

MIG1, TUP1 and NRG1 mediated yeast to hyphal morphogenesis inhibition in Candida albicans by ganciclovir.

Candida albicans is a polymorphic human fungal pathogen and the prime etiological agent responsible for candidiasis. The main two aspects of C. albicans virulence that have been suggested are yeast-to-hyphal (Y-H) morphological transitions and biofilm development. Anti-fungal agents targeting these virulence attributes enhances the antifungal drug development process. Repositioning with other non-fungal drugs offered a one of the new strategies and a potential alternative option to counter the urgent need for antifungal drug development. In the current study, an antiviral drug ganciclovir was screened as an antifungal agent against ATCC 90028, 10231 and clinical isolate (C1). Ganciclovir at 0.5 mg/ml concentration reduced 50% hyphal development on a silicon-based urinary catheter and was visualized using scanning electron microscopy. Ganciclovir reduced ergosterol biosynthesis in both strains and C1 isolate of C. albicans in a concentration-dependent manner. Additionally, a gene expression profile study showed that ganciclovir treatment resulted in upregulation of hyphal-specific repressors MIG1, TUP1, and NRG1 in C. albicans. Additionally, an in vivo study on the Bombyx mori silkworm model further evidenced the virulence inhibitory ability of ganciclovir (0.5 mg/ml) against C. albicans. This is the first report that explore the novel anti-morphogenic activities of ganciclovir against the pathogenic C. albicans strains, along with clinical isolates. Further, ganciclovir may be considered for therapeutic purpose after combinations with standard antifungal agents.

In vitro antifungal activity of MMV Pathogen Box® compounds alone or in combination with antifungal drugs against mucormycosis agents.

Mucormycosis is a severe fungal infection that demands immediate and decisive intervention upon suspicion. The causative agents of mucormycosis exhibit inherent resistance to echinocandins and voriconazole, and their in vitro susceptibility to terbinafine is highly variable and species-specific. Considering these factors and the limitations of currently available antifungal therapies, the identification of novel antifungals with potent activity against mucormycosis is of paramount importance. This study aims to identify compounds from the MMV Pathogen Box® presenting antifungal activity against selected mucormycosis agents and to evaluate their potential synergistic effects when combined with antifungal drugs. A screening of the Pathogen Box® compounds was conducted, isolated or in combination with sub-inhibitory concentrations of amphotericin B, isavuconazole or posaconazole, against a Rhizopus oryzae strain. Hits from the screenings were further evaluated against eight Mucoralean strains for minimal inhibitory and fungicidal concentration determinations and to confirm synergistic interactions using the checkerboard method. Ultrastructural studies were performed using scanning electron microscopy. MMV675968 exhibited fungicidal activity against a R. oryzae strain. All but one Rhizopus spp. strains presented MIC ≤ 1 µg/mL, with a geometric mean of 0.78 µg/mL observed across all isolates for this compound, which did not change significantly the cellular structure of this fungus. The combination screening with antifungal drugs revealed six additional compounds potentially active against the R. oryzae strain, two of them demonstrated proven synergism through the checkerboard assay. This first study with the MMV Pathogen Box® and Zigomycetes highlights promising new treatment options for mucormycosis in the future.

Antifungal and antibiofilm effect of duloxetine hydrochloride against Cryptococcus neoformans and Cryptococcus gattii.

Cryptococcosis is an invasive mycosis caused mainly by Cryptococcus gattii and C. neoformans and is treated with amphotericin B (AMB), fluconazole and 5-fluorocytosine. However, antifungal resistance, limited and toxic antifungal arsenal stimulate the search for therapeutic strategies such as drug repurposing. Among the repurposed drugs studied, the selective serotonin reuptake inhibitors (SSRIs) have shown activity against Cryptococcus spp. However, little is known about the antifungal effect of duloxetine hydrochloride (DH), a selective serotonin and norepinephrine reuptake inhibitor (SSNRI), against C. neoformans and C. gattii. In this study, DH inhibited the growth of several C. neoformans and C. gattii strains at concentrations ranging from 15.62 to 62.50 µg/mL. In addition, DH exhibited fungicidal activity ranging from 15.62 to 250 µg/mL. In biofilm, DH treatment reduced Cryptococcus spp. biomass at a level comparable to AMB, with a significant reduction (85%) for C. neoformans biofilms. The metabolic activity of C. neoformans and C. gattii biofilms decreased significantly (99%) after treatment with DH. Scanning electron micrographs confirmed the anti-biofilm activity of DH, as isolated cells could be observed after treatment. In conclusion, DH showed promising antifungal activity against planktonic cells and biofilms of C. neoformans and C. gattii, opening perspectives for further studies with DH in vivo.

Drug Repurposing and Personalized Treatment Strategies for Bipolar Disorder Using Transcriptomic.

OBJECTIVE: The present study combined transcriptomic data and computational techniques based on gene expression signatures to identify novel bioactive compounds or FDA-approved drugs for the management of Bipolar Disorder (BD). METHODS: Five transcriptomic datasets, comprising a total of 165 blood samples from BD case-control, were selected from the Gene Expression Omnibus repository (GEO). The number of subjects varied from 6 to 60, with a mean age ranging from 35 to 48, with a gender variation between them. Most of the patients were on pharmacological treatment. Master Regulator Analysis (MRA) and Gene Set Enrichment Analysis (GSEA) were performed to identify statistically significant genes between BD and HC and their association with the mood states of BD. Additionally, existing molecules with the potential to reverse the transcriptomic profiles of disease-altered regulons in BD were identified using the LINCS and cMap databases. RESULTS: MRA identified 59 potential MRs candidates modulating the regulatory units enriched with genes altered in BD, while the GSEA identified 134 enriched genes, and a total of 982 regulons had their activation state determined. Both analyses showed genes exclusively associated with mania, depression, or euthymia, and some genes were common between the three mood states. We identified bioactive compounds and licensed drug candidates, including antihypertensives and antineoplastics, as promising candidates for treating BD. Nevertheless, experimental validation is essential to authenticate these findings in subsequent studies. CONCLUSION: Although preliminary, our data provides some insights regarding the biological patterns of BD into distinct mood states and potential therapeutic targets. The combined transcriptomic and bioinformatics strategy offers a route to advance drug discovery and personalized medicine by tapping into gene expression information.

In vitro activity of the anthelmintic drug niclosamide against Sporothrix spp. strains with distinct genetic and antifungal susceptibility backgrounds.

The drugs available to treat sporotrichosis, an important yet neglected fungal infection, are limited. Some Sporothrix spp. strains present reduced susceptibility to these antifungals. Furthermore, some patients may not be indicated to use these drugs, while others may not respond to the therapy. The anthelmintic drug niclosamide is fungicidal against the Sporothrix brasiliensis type strain. This study aimed to evaluate whether niclosamide also has antifungal activity against Sporothrix globosa, Sporothrix schenckii and other S. brasiliensis strains with distinct genotypes and antifungal susceptibility status. Minimal inhibitory and fungicidal concentrations (MIC and MFC, respectively) were determined using the microdilution method according to the CLSI protocol. The checkerboard method was employed to evaluate niclosamide synergism with drugs used in sporotrichosis treatment. Metabolic activity of the strains under niclosamide treatment was evaluated using the resazurin dye. Niclosamide was active against all S. brasiliensis strains (n = 17), but it was ineffective (MIC > 20 µM) for some strains (n = 4) of other pathogenic Sporothrix species. Niclosamide MIC values for Sporothrix spp. were similar for mycelial and yeast-like forms of the strains (P = 0.6604). Niclosamide was fungicidal (MFC/MIC ratio ≤ 2) for most strains studied (89%). Niclosamide activity against S. brasiliensis is independent of the fungal genotype or non-wild-type phenotypes for amphotericin B, itraconazole, or terbinafine. These antifungal drugs presented indifferent interactions with niclosamide. Niclosamide has demonstrated potential for repurposing as a treatment for sporotrichosis, particularly in S. brasiliensis cases, instigating in vivo studies to validate the in vitro findings.

Identification of CYFIP2 Arg87Cys Ligands via In Silico and In Vitro Approaches.

The advancement of next-generation sequencing has enabled the identification of specific mutations associated with early infantile epileptic encephalopathies (EIEEs). In EIEE, epileptic spasms and seizures that occur since early childhood lead to impaired neurological development. The CYFIP2 p.Arg87Cys variant was recently related to EIEE. CYFIP2 participates in the Wave Regulatory Complex (WRC), which is related to the regulation of actin dynamics. The variant residue is at the interface between the CYFIP2 protein and WAVE1 protein inside the WRC. Thus, the weakening of this interaction induced by the residue modification, which also causes the flexibilization of the loop 80-110 within the CYFIP2 structure, allows the constant activation of the WCR. This study aimed to identify ligands for CYFIP2 p.Arg87Cys and potential therapy targets using in silico in vitro approaches. Models of different CYFIP2 versions were constructed, and molecular docking analyses were conducted. A total of 3946 ligands from the PDE3 and Drugbank databases were screened, leading to the identification of 11 compounds that selectively bind to the variant protein. The impact of binding in CYFIP2 was also evaluated using a thermal stability assay. These findings contribute to a better understanding of CYFIP2's functional role in pathology and can guide more in vitro experiments, facilitating the development of targeted therapies for CYFIP2-related conditions.

Mechanistic Insights about Sorafenib-, Valproic Acid- and Metformin-Induced Cell Death in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is among the main causes of death by cancer worldwide, representing about 80-90% of all liver cancers. Treatments available for advanced HCC include atezolizumab, bevacizumab, sorafenib, among others. Atezolizumab and bevacizumab are immunological options recently incorporated into first-line treatments, along with sorafenib, for which great treatment achievements have been reached. However, sorafenib resistance is developed in most patients, and therapeutical combinations targeting cancer hallmark mechanisms and intracellular signaling have been proposed. In this review, we compiled evidence of the mechanisms of cell death caused by sorafenib administered alone or in combination with valproic acid and metformin and discussed them from a molecular perspective.

Doxycycline reduces liver and kidney injuries in a rat hemorrhagic shock model.

BACKGROUND: Hemorrhagic shock (HS), which causes insufficient tissue perfusion, can result in multiple organ failure (MOF) and death. This study aimed to evaluate whether doxycycline (DOX) protects cardiovascular, kidney, and liver tissue from damage in a rat model of HS. Immediately before the resuscitation, DOX (10 mg/kg; i.v.) was administered, and its protective effects were assessed 24 h later. Mean arterial pressure, renal blood flow, heart rate, vasoactive drug response, and blood markers such as urea, creatinine, AST, ALT, CPK, CPR, and NOx levels were determined. RESULTS: We showed that DOX has a significant effect on renal blood flow and on urea, creatinine, AST, ALT, CPK, and NOx. Morphologically, DOX reduced the inflammatory process in the liver tissue. CONCLUSIONS: We conclude that DOX protects the liver and kidney against injury and dysfunction in a HS model and could be a strategy to reduce organ damage associated with ischemia-and-reperfusion injury.

Similarity searching for anticandidal agents employing a repurposing approach.

Fungal infections caused by Candida are still a public health concern. Particularly, the resistance to traditional chemotherapeutic agents is a major issue that requires efforts to develop new therapies. One of the most interesting approaches to finding new active compounds is drug repurposing aided by computational methods. In this work, two databases containing anticandidal agents and drugs were studied employing cheminformatics and compared by similarity methods. The results showed 36 drugs with high similarities to some candicidals. From these drugs, trimetozin, osalmid and metochalcone were evaluated against C. albicans (18804), C. glabrata (90030), and miconazole-resistant strain C. glabrata (32554). Osalmid and metochalcone were the best, with activity in the micromolar range. These findings represent an opportunity to continue with the research on the potential antifungal application of osalmid and metochalcone as well as the design of structurally related derivatives.