Preclinical Research Articles

Oligodendrocyte Injury in Multiple Sclerosis.

Introduction: Multiple sclerosis (MS) is a chronic autoimmune disorder of the central nervous system (CNS), marked by inflammation, demyelination, and significant oligodendrocyte injury. This disease arises from a complex interplay of genetic predispositions and environmental triggers that drive immune-mediated damage to oligodendrocytes and myelin proteins. This research paper explores the multifaceted aspects of oligodendrocyte injury in MS, ranging from underlying pathophysiological mechanisms to potential therapeutic interventions and translational implications for clinical practice. Oligodendrocyte damage in MS occurs via multiple mechanisms, including metabolic stress, oxidative damage, and cytokine-induced apoptosis, mainly mediated by interferon-gamma (IFN-γ) signaling. This process exacerbates neuroinflammation and contributes to disease progression. Emerging therapeutic strategies, such as targeting metabolic pathways, reducing oxidative stress, and enhancing autophagy, have demonstrated potential in preclinical studies. Furthermore, stem cell therapies are being explored for their ability to regenerate oligodendrocytes and restore myelin integrity. Conclusions: The intricate interplay among oligodendrocyte injury, demyelination, and neuroinflammation is central to multiple sclerosis (MS) pathogenesis. Oligodendrocytes safeguard myelin in the CNS, facing challenges from immune attacks to metabolic stress. Understanding oligodendrocyte dysfunction is vital for targeted therapies that suppress immune damage and promote remyelination and CNS repair. MS's etiology,

Unlocking the Therapeutic Potential of Algae-Derived Compounds in Hematological Malignancies.

Algae are a rich source of bioactive compounds that have a wide range of beneficial effects on human health and can show significant potential in the treatment of hematological malignancies such as leukemia, lymphoma, and multiple myeloma. These diseases often pose a therapeutic challenge despite recent advances in treatment (e.g., the use of immunomodulatory drugs, proteasome inhibitors, CD38 monoclonal antibodies, stem cell transplant, and targeted therapy). A considerable number of patients experience relapses or resistance to the applied therapies. Algal compounds, alone or in combination with chemotherapy or other more advanced therapies, have exhibited antitumor and immunomodulatory effects in preclinical studies that may improve disease outcomes. These include the ability to induce apoptosis, inhibit tumor growth, and improve immune responses. However, most of these studies are conducted in vitro, often without in vivo validation or clinical trials. This paper summarizes the current evidence on the in vitro effects of algae extracts and isolated compounds on leukemia, lymphoma, and myeloma cell lines. In addition, we address the current advances in the application of algae-derived compounds as targeted drug carriers and their synergistic potential against hematologic malignancies.

Detection of Cancer Stem Cells from Patient Samples.

The existence of cancer stem cells (CSCs) in various tumors has become increasingly clear in addition to their prominent role in therapy resistance, metastasis, and recurrence. For early diagnosis, disease progression monitoring, and targeting, there is a high demand for clinical-grade methods for quantitative measurement of CSCs from patient samples. Despite years of active research, standard measurement of CSCs has not yet reached clinical settings, especially in the case of solid tumors. This is because detecting this plastic heterogeneous population of cells is not straightforward. This review summarizes various techniques, highlighting their benefits and limitations in detecting CSCs from patient samples. In addition, methods designed to detect CSCs based on secreted and niche-associated signaling factors are reviewed. Spatial and single-cell methods for analyzing patient tumor tissues and noninvasive techniques such as liquid biopsy and in vivo imaging are discussed. Additionally, methods recently established in laboratories, preclinical studies, and clinical assays are covered. Finally, we discuss the characteristics of an ideal method as we look toward the future.

Mechanisms of apoptosis-related non-coding RNAs in ovarian cancer: a narrative review.

Ovarian cancer remains a major challenge in oncology due to its complex biology and late-stage diagnosis. Recent advances in molecular biology have highlighted the crucial role of non-coding RNAs (ncRNAs) in regulating apoptosis and cancer progression. NcRNAs, including microRNAs, long non-coding RNAs, and circular RNAs, have emerged as significant players in the molecular networks governing ovarian cancer. Despite these insights, the precise mechanisms by which ncRNAs influence ovarian cancer pathology are not fully understood. This complexity, combined with the heterogeneity of the disease and the development of treatment resistance, poses substantial obstacles to effective therapeutic development. Additionally, the lack of reliable early detection methods further complicates treatment strategies. This manuscript reviews the current state of research on ncRNAs in ovarian cancer, discusses the challenges in translating these findings into clinical applications, and outlines potential future directions. Emphasis is placed on the need for integrated approaches to unravel the intricate roles of ncRNAs, improve early detection, and develop personalized treatment strategies to address the diverse and evolving nature of ovarian cancer. While these findings provide valuable insights, it is crucial to recognize that many results are based on preclinical studies and require further validation to establish their clinical applicability.

Inhibition of cap-dependent endonuclease in influenza virus with ADC189: a pre-clinical analysis and phase I trial.

ADC189 is a novel drug of cap-dependent endonuclease inhibitor. In our study, its antiviral efficacy was evaluated in vitro and in vivo, and compared with baloxavir marboxil and oseltamivir. A first-in-human phase I study in healthy volunteers included single ascending dose (SAD) and food effect (FE) parts. In the preclinical study, ADC189 showed potent antiviral activity against various types of influenza viruses, including H1N1, H3N2, influenza B virus, and highly pathogenic avian influenza, comparable to baloxavir marboxil. Additionally, ADC189 exhibited much better antiviral efficacy than oseltamivir in H1N1 infected mice. In the phase I study, ADC189 was rapidly metabolized to ADC189-I07, and its exposure increased proportionally with the dose. The terminal elimination half-life (T1/2) ranged from 76.69 to 98.28 hours. Of note, food had no effect on the concentration, clearance, and exposure of ADC189. It was well tolerated, with few treatment-emergent adverse events (TEAEs) reported and no serious adverse events (SAEs). ADC189 demonstrated excellent antiviral efficacy both in vitro and in vivo. It was safe, well-tolerated, and had favorable pharmacokinetic characteristics in healthy volunteers, supporting its potential for single oral dosing in clinical practice.

Prospective Harmonization, Common Data Elements, and Sharing Strategies for Multicenter Pre-Clinical Traumatic Brain Injury Research in the Translational Outcomes Project in Neurotrauma Consortium.

Effective team science requires procedural harmonization for rigor and reproducibility. Multicenter studies across experimental modalities (domains) can help accelerate translation. The Translational Outcomes Project in NeuroTrauma (TOP-NT) is a pre-clinical traumatic brain injury (TBI) consortium charged with establishing and validating noninvasive TBI assessment tools through team science. Here, we present practical approaches for harmonization of TBI research across five centers providing needed vocabulary and structure to achieve centralized data organization and use. This includes data sharing as an essential step that enables validating data between domains, evaluating reproducibility between sites, and performing multimodal analyses. As part of this process, TOP-NT (1) produced a library of TBI-relevant standard operating procedures to coordinate workflow, (2) aligned 481 pre-clinical and clinical common data elements (CDEs), and (3) generated 272 new pre-clinical TBI CDEs. This consortium then (4) connected diverse data types to validate assessments across domains and to allow multivariable TBI phenotyping. Lastly, TOP-NT (5) specified technical quality controls for pre-clinical studies. These harmonization tools can facilitate reproducibility in team science, help distinguish a wide injury spectrum from technical variability, apply quality-controls, and ease higher level data analyses. TOP-NT uses three rat TBI models across four sites. Each site collects primary outcome measures, including magnetic resonance imaging (MRI) protocols and blood biomarkers of neuronal and glial injury, validated by histopathology and behavioral outcomes. Collected data are organized using the 481 TOP-NT pre-clinical CDEs, covering surgical, behavioral, biomarker, MRI, and quantitative histopathological methods. We report data curation steps suited for data storage using the Open Data Commons for TBI as a centralized data repository, allowing unbiased cross-site analysis. This approach leads to introducing a higher level, syndromic understanding of TBI signatures. TOP-NT authors outline a semantic and structural framework suggesting strategies for robust pre-clinical research in multicenter trials to improve translatability for TBI assessments. [Figure: see text].

A promising future for breast cancer therapy with hydroxamic acid-based histone deacetylase inhibitors.

Histone deacetylases (HDACs) play a critical role in chromatin remodelling and modulating the activity of various histone proteins. Aberrant HDAC functions has been related to the progression of breast cancer (BC), making HDAC inhibitors (HDACi) promising small-molecule therapeutics for its treatment. Hydroxamic acid (HA) is a significant pharmacophore due to its strong metal-chelating ability, HDAC inhibition properties, MMP inhibition abilities, and more. They were found to increase the efficacy of the approved drugs when used in combination. In this review we presented bioinformatic analysis using available data from the Cancer Genome Atlas and Genotype-Tissue Expression databases, outlined the recent advancements in the application of HA-based HDACi for BC during preclinical investigation and clinical trials, tried to offer the rationale for targeting HDAC in BC with HA-based HDACi, summarised the challenges faced in the successful clinical application of HDACi, and proposed potential strategies to address these challenges, aiming to enhance treatment outcomes in BC. Abbreviations: ABCG2, ATP-binding cassette super-family G member 2; ABC, ATP-binding cassette; ADP, Adenosine diphosphate; APC, Antigen presenting cell; AML, Acute myeloid leukemia; ARH1, Aplysia ras homolog 1; BCRP, Breast cancer resistance protein; BRCA, Breast invasive carcinoma; Bax, B-cell lymphoma associated X; CK5, Cytokeratin 5; CK14, Cytokeratin 14; CK17, Cytokeratin 17; CoRESTMiDAC, Co-repressor for element-1-silencing transcription factor; CRM1, Chromosomal maintenance 1; CTCL, Cutaneous T-cell lymphoma; DNMT, DNA methyltransferase; DFS, Disease-free survival; ER, Oestrogen receptor; EMT, Epithelial-mesenchymal transition; FGFR1, Fibroblast growth factor receptor 1; GEPIA, Gene Expression Profiling Interactive Analysis; GTEx, Genotype tissue expression; HAT, Histone acetylase; HDAC, Histone deacetylase; HDF, Human dermal fibroblast; HER2, Human epidermal growth factor receptor 2; HDLP, Histone deacetylase-like protein; Hsp90, Heat shock protein 90; HSF1, Heat shock factor 1; HeLa, Henrietta Lacks; HER1, Human epidermal growth factor receptor 1; IARC, International Agency for Research on Cancer; IL-10, Interleukin-10; KAP1, KRAB associated protein 1; MDM2, Mouse double minute 2 homolog; MDR, Multidrug resistance; MCF-7, Michigan cancer foundation-7; MEF-2, Myocyte enhancer factor-2MMP- Matrix metalloproteinase; NAD, Nicotinamide adenine dinucleotide; NuRD, Nucleosome remodelling and deacetylation; NF- κ B, Nuclear factor kappa light chain enhancer of activated B cell; NES, Nuclear export signal; NLS, Nuclear localization signal; NCoR, Nuclear receptor corepressor; NCT, National clinical trial; OS, Overall survival; PR, Progesterone receptor; PI3K, Phosphoinositide 3-kinase; PAX3, Paired box gene 3; P-gp, P-glycoprotein; ROS, Reactive oxygen species; SIRT, Sirtuin; SMRT, Silencing mediator for retinoid and thyroid receptor; STAT3, Signal transducer and activator of transcription-3; SAR, Structure-activity relationship; SHP1, Src homology region 2 domain-containing phosphatase 1; SAHA, Suberoylanilide hydroxamic acid; SMEDDS, Self micro emulsifying drug delivery system; TNBC, Triple-negative breast cancer; TSA, Trichostatin A; ZBG, Zinc binding group.

Evaluation of host immune responses to Mycobacteriophage Fionnbharth by route of delivery

For much of the last decade, tuberculosis (TB) was the leading cause of mortality due to an infectious pathogen (Mycobacterium tuberculosis, M.tb). Approximately 1.3 million deaths in 2023 worldwide were attributed to TB disease. Focused intervention strategies to block transmission would significantly reduce the global health burden of TB. Mycobacteriophages (phages) are a sorely underutilized biologic therapy for the pathogen M.tb, and here we aimed to address outstanding questions about their utility for clinical applications. We aimed to determine the impact of repeated mucosal or intravenous (IV) delivery of representative anti-M.tb phage FionnbharthΔ45Δ47 (Fionnbharth) in a preclinical mouse model. In addition, we specifically sought to understand which route induced anti-phage antibodies, which may reduce the long-term impact of phage therapy. C57BL/6 mice were dosed weekly for 6 weeks by either route and serum and bronchoalveolar lavage fluid (BALf) were evaluated for anti-phage humoral responses by ELISA. We found that aerosol delivery disperses phage across all lung lobes where M.tb is also found after experimental infection by the same route. Repeated aerosol delivery was well tolerated and did not induce robust neutralizing humoral immunity. In contrast, Mice receiving IV phage developed increasing magnitude and neutralizing total IgG and IgA responses over time. To determine whether pre-treatment environmental exposure to Fionnbharth-like phages could induce antibody responses that are potentially neutralizing, ~ 500 human plasma samples from normal donors were evaluated by ELISA. We observed that 5% of samples had antibodies to Fionnbharth (with end point titers > 10− 3 dilution), although none were neutralizing. Furthermore, we found that highly-purified phage preparations did not activate mouse or human derived toll like receptor (TLR) 4 or TLR9 in HEKblue reporter assays. These data together support using Fionnbharth in anti-M.tb therapy phage cocktail strategies and that aerosol delivery should be prioritized for further efficacy testing.

Artificial intelligence in drug development.

Drug development is a complex and time-consuming endeavor that traditionally relies on the experience of drug developers and trial-and-error experimentation. The advent of artificial intelligence (AI) technologies, particularly emerging large language models and generative AI, is poised to redefine this paradigm. The integration of AI-driven methodologies into the drug development pipeline has already heralded subtle yet meaningful enhancements in both the efficiency and effectiveness of this process. Here we present an overview of recent advancements in AI applications across the entire drug development workflow, encompassing the identification of disease targets, drug discovery, preclinical and clinical studies, and post-market surveillance. Lastly, we critically examine the prevailing challenges to highlight promising future research directions in AI-augmented drug development.

Potential therapeutics and vaccines: Current progress and challenges in developing antiviral treatments or vaccines for Oropouche virus.

Oropouche virus (OROV), an emerging arbovirus, poses a significant public health challenge in tropical and subtropical regions, with no licensed vaccines or antiviral therapies currently available. This review explores recent advancements in therapeutic strategies and vaccine development for OROV, focusing on molecular mechanisms of viral replication, identification of potential antiviral targets, and the role of immunotherapy in managing infections. Promising antiviral candidates, including ribavirin, mycophenolic acid, and interferon, have demonstrated efficacy in in vitro studies, offering a foundation for further investigation. The challenges of preclinical and clinical development, such as high mutation rates, immune response variability, and vaccine delivery hurdles, are critically analyzed. By addressing the progress and remaining gaps, this article aims to provide a comprehensive overview to inform future research and facilitate the development of effective antiviral strategies and vaccines for OROV.

Genetic context modulates aging and degeneration in the murine retina

BackgroundAge is the principal risk factor for neurodegeneration in both the retina and brain. The retina and brain share many biological properties; thus, insights into retinal aging and degeneration may shed light onto similar processes in the brain. Genetic makeup strongly influences susceptibility to age-related retinal disease. However, studies investigating retinal aging have not sufficiently accounted for genetic diversity. Therefore, examining molecular aging in the retina across different genetic backgrounds will enhance our understanding of human-relevant aging and degeneration in both the retina and brain—potentially improving therapeutic approaches to these debilitating conditions.MethodsTranscriptomics and proteomics were employed to elucidate retinal aging signatures in nine genetically diverse mouse strains (C57BL/6J, 129S1/SvlmJ, NZO/HlLtJ, WSB/EiJ, CAST/EiJ, PWK/PhK, NOD/ShiLtJ, A/J, and BALB/cJ) across lifespan. These data predicted human disease-relevant changes in WSB and NZO strains. Accordingly, B6, WSB, and NZO mice were subjected to human-relevant in vivo examinations at 4, 8, 12, and/or 18M, including: slit lamp, fundus imaging, optical coherence tomography, fluorescein angiography, and pattern/full-field electroretinography. Retinal morphology, vascular structure, and cell counts were assessed ex vivo.ResultsWe identified common molecular aging signatures across the nine mouse strains, which included genes associated with photoreceptor function and immune activation. Genetic background strongly modulated these aging signatures. Analysis of cell type-specific marker genes predicted age-related loss of photoreceptors and retinal ganglion cells (RGCs) in WSB and NZO, respectively. Fundus exams revealed retinitis pigmentosa-relevant pigmentary abnormalities in WSB retinas and diabetic retinopathy (DR)-relevant cotton wool spots and exudates in NZO retinas. Profound photoreceptor dysfunction and loss were confirmed in WSB. Molecular analyses indicated changes in photoreceptor-specific proteins prior to loss, suggesting photoreceptor-intrinsic dysfunction in WSB. In addition, age-associated RGC dysfunction, loss, and concomitant microvascular dysfunction were observed in NZO mice. Proteomic analyses revealed an early reduction in protective antioxidant processes, which may underlie increased susceptibility to DR-relevant pathology in NZO.ConclusionsGenetic context is a strong determinant of retinal aging, and our multi-omics resource can aid in understanding age-related diseases of the eye and brain. Our investigations identified and validated WSB and NZO mice as improved preclinical models relevant to common retinal neurodegenerative diseases.

The roles of IDH2 and glutathione metabolism in cetuximab resistance in head and neck squamous cell carcinoma investigated by metabolomics and transcriptomics.

Cetuximab resistance is a significant challenge in the treatment of head and neck squamous cell carcinoma (HNSCC). In this study, cetuximab-resistant HNSCC cell lines were established, and untargeted metabolomics was used to detect differences in metabolite profiles between sensitive and resistant cell lines. It was found that glutathione metabolism significantly differed between the sensitive and resistant lines. Combining these findings with transcriptome data, correlation analysis of metabolites revealed that IDH2 regulated glutathione metabolism and contributed to cetuximab resistance in FaDu cells. In vitro experiments showed that IDH2 was highly expressed in FaDu-CR cells, and IDH2 knockdown significantly enhanced the sensitivity of FaDu and FaDu-CR cells to cetuximab. IDH2 knockdown reduced GSH levels and GPX4 expression in FaDu and FaDu-CR cells under cetuximab treatment, while increasing lipid ROS levels. In vivo experiments demonstrated that IDH2 knockdown decreased the tumorigenic ability of FaDu-CR cells in nude mice treated with cetuximab, as well as reduced GPX4 and Ki67 levels in tumor tissues. In conclusion, IDH2 regulated glutathione metabolism and contributed to cetuximab resistance in HNSCC. This study explores strategies to ameliorate cetuximab resistance in HNSCC preclinical models, providing new insights for reversing cetuximab resistance in HNSCC.

Exploring Integrin α5β1 as a Potential Therapeutic Target for Pulmonary Arterial Hypertension: Insights From Comprehensive Multicenter Preclinical Studies.

Pulmonary arterial hypertension (PAH) is characterized by obliterative vascular remodeling of the small pulmonary arteries (PAs) and progressive increase in pulmonary vascular resistance leading to right ventricular failure. Although several drugs are approved for the treatment of PAH, mortality rates remain high. Accumulating evidence supports a pathological function of integrins in vessel remodeling, which are gaining renewed interest as drug targets. However, their role in PAH remains largely unexplored. The expression of the RGD (arginylglycylaspartic acid)-binding integrin α5β1 was assessed in PAs, PA smooth muscle cells, and PA endothelial cells from patients with PAH and controls using NanoString, immunoblotting, and Mesoscale Discovery assays. RNA sequencing was conducted to identify gene networks regulated by α5β1 inhibition in PAH PA smooth muscle cells. The therapeutic efficacy of α5β1 inhibition was evaluated using a novel small molecule inhibitor and selective neutralizing antibodies in Sugen/hypoxia and monocrotaline rat models, with validation by an external contract research organization. Comparisons were made against standard-of-care therapies (ie, macitentan, tadalafil) and sotatercept and efficacy was assessed using echocardiographic, hemodynamic, and histological assessments. Ex vivo studies using human precision-cut lung slices were performed to further assess the effects of α5β1 inhibition on pulmonary vascular remodeling. We found that the arginine-glycine-aspartate RGD-binding integrin α5β1 is upregulated in PA endothelial cells and PA smooth muscle cells from patients with PAH and remodeled PAs from animal models. Blockade of the integrin α5β1 or depletion of the α5 subunit downregulated FOXM1 (forkhead box protein M1)-regulated gene networks, resulting in mitotic defects and inhibition of the pro-proliferative and apoptosis-resistant phenotype of PAH cells. We demonstrated that α5β1 integrin blockade safely attenuates pulmonary vascular remodeling and improves hemodynamics and right ventricular function and matched or exceeded the efficacy of standard of care and sotatercept in multiple preclinical models. Ex vivo studies further validated its potential in reversing advanced remodeling in human precision-cut lung slices. These findings establish α5β1 integrin as a pivotal driver of PAH pathology and we propose its inhibition as a novel, safe, and effective therapeutic strategy for PAH.

Genetic deficiency or pharmacological inhibition of cGAS-STING signalling suppresses kidney inflammation and fibrosis.

Chronic kidney disease (CKD) is characterised by inflammation, which can lead to tubular atrophy and fibrosis. The molecular mechanisms are not well understood. In this study, we investigated the functional role of the cyclic GMP-AMP synthase (cGAS)- stimulator of interferon genes (STING) signalling in renal inflammation and fibrosis. Mice with global cGAS deficiency or global or myeloid cell-specific STING deficiency or wild-type mice treated with RU.521, a selective cGAS inhibitor, were used to examine the role of cGAS-STING signalling in renal inflammation and fibrosis in a preclinical model of obstructive nephropathy in vivo. Bone marrow-derived macrophages were used to determine whether tubular epithelial cell-derived DNA can activate cGAS-STING signalling in vitro. Following obstructive injury, cGAS-STING signalling was activated in the kidneys during the development of renal fibrosis. Mice with deficiency of cGAS or STING exhibited significantly less macrophage proinflammatory activation, myofibroblast formation, total collagen deposition, and extracellular matrix (ECM) protein production in the kidneys following obstructive injury. Pharmacological inhibition of cGAS with RU.521 reduced macrophage proinflammatory activation, suppressed myofibroblast formation, and attenuated kidney fibrosis following obstructive injury. Mechanistically, cGAS-STING signalling in macrophages is activated by double-stranded DNA released from damaged tubular epithelial cells, which induces inflammatory responses. Our study identifies the cGAS-STING signalling pathway as a critical regulator of macrophage proinflammatory activation during the development of renal fibrosis. Therefore, inhibition of cGAS-STING signalling may represent a novel therapeutic strategy for CKD.

Oxidative and Excitatory Neurotoxic Stresses in CRISPR/Cas9-Induced Kynurenine Aminotransferase Knockout Mice: A Novel Model for Despair-Based Depression and Post-Traumatic Stress Disorder.

Memory and emotion are especially vulnerable to psychiatric disorders such as post-traumatic stress disorder (PTSD), which is linked to disruptions in serotonin (5-HT) metabolism. Over 90% of the 5-HT precursor tryptophan (Trp) is metabolized via the Trp-kynurenine (KYN) metabolic pathway, which generates a variety of bioactive molecules. Dysregulation of KYN metabolism, particularly low levels of kynurenic acid (KYNA), appears to be linked to neuropsychiatric disorders. The majority of KYNA is produced by the aadat (kat2) gene-encoded mitochondrial kynurenine aminotransferase (KAT) isotype 2. Little is known about the consequences of deleting the KYN enzyme gene. In CRISPR/Cas9-induced aadat knockout (kat2-/-) mice, we examined the effects on emotion, memory, motor function, Trp and its metabolite levels, enzyme activities in the plasma and urine of 8-week-old males compared to wild-type mice. Transgenic mice showed more depressive-like behaviors in the forced swim test, but not in the tail suspension, anxiety, or memory tests. They also had fewer center field and corner entries, shorter walking distances, and fewer jumping counts in the open field test. Plasma metabolite levels are generally consistent with those of urine: antioxidant KYNs, 5-hydroxyindoleacetic acid, and indole-3-acetic acid levels were lower; enzyme activities in KATs, kynureninase, and monoamine oxidase/aldehyde dehydrogenase were lower, but kynurenine 3-monooxygenase was higher; and oxidative stress and excitotoxicity indices were higher. Transgenic mice displayed depression-like behavior in a learned helplessness model, emotional indifference, and motor deficits, coupled with a decrease in KYNA, a shift of Trp metabolism toward the KYN-3-hydroxykynurenine pathway, and a partial decrease in the gut microbial Trp-indole pathway metabolite. This is the first evidence that deleting the aadat gene induces depression-like behaviors uniquely linked to experiences of despair, which appear to be associated with excitatory neurotoxic and oxidative stresses. This may lead to the development of a double-hit preclinical model in despair-based depression, a better understanding of these complex conditions, and more effective therapeutic strategies by elucidating the relationship between Trp metabolism and PTSD pathogenesis.

Disitamab vedotin in preclinical models of HER2-positive breast and gastric cancers resistant to trastuzumab emtansine and trastuzumab deruxtecan.

Most HER2-positive breast or gastric cancers eventually become resistant to the approved anti-HER2 antibody-drug conjugates (ADC) trastuzumab emtansine (T-DM1) and trastuzumab deruxtecan (T-DXd). Disitamab vedotin (DV) is a novel anti-HER2 ADC that binds to a different epitope on HER2 compared to trastuzumab. We assessed the efficacy of DV in breast and gastric cancer cell lines and xenografts, including tumor models resistant to T-DM1 and T-DXd. Additionally, we investigated whether combining two anti-HER2 ADCs could enhance the efficacy of the individual ADCs. The efficacy of DV, T-DM1, and T-DXd, both as single agents and in combinations, was assessed using an AlamarBlue cell proliferation assay in HER2-positive breast and gastric cancer cell lines, including those resistant to T-DM1 and T-DXd. The efficacy of DV was evaluated also in breast and gastric cancer SCID mouse xenografts that had progressed on T-DM1 and/or T-DXd. ADC combinations were tested in breast and gastric cancer xenografts. DV was effective in cell lines resistant to T-DM1 and/or T-DXd, and it inhibited the growth of breast and gastric cancer xenografts that had progressed on T-DM1 and/or T-DXd. The combinations of DV plus T-DM1 and DV plus T-DXd showed greater efficacy than the corresponding single agents in both breast and gastric cancer cell lines and xenografts. DV was effective in treating breast and gastric cancer xenograft tumors resistant to T-DM1 and/or T-DXd. The combination of DV with T-DM1 or T-DXd demonstrated promising activity.

The Development of Opioid Vaccines as A Novel Strategy for the Treatment of Opioid Use Disorder and Overdose Prevention.

Opioid use disorder (OUD) affects over 40 million people worldwide, creating significant social and economic burdens. Medication for opioid use disorder (MOUD) is often considered the primary treatment approach for OUD. MOUD, including methadone, buprenorphine, and naltrexone is effective for some, but its benefits may be limited by poor adherence to treatment recommendations. Immunopharmacotherapy offers an innovative approach by using vaccines to generate antibodies that neutralize opioids, blocking them from crossing the blood-brain barrier and reducing their psychoactive effects. To date, only three clinical trials for opioid vaccines have been published. While these studies demonstrated the potential of opioid vaccines for relapse prevention, there is currently no standardized protocol for evaluating their effectiveness. We have reviewed recent preclinical studies that demonstrated the efficacy of vaccines targeting opioids, including heroin, morphine, oxycodone, hydrocodone, and fentanyl. These studies showed that vaccines against opioids reduced drug reinforcement, decreased opioid-induced antinociception, and increased survival rates against lethal opioid doses. These studies also demonstrated the importance of vaccine formulation and the use of adjuvants in enhancing antibody production and specificity. Finally, we highlighted the strengths and concerns associated with the opioid vaccine treatment, including ethical considerations.

Soluble guanylate cyclase stimulators and activators as potential antihypertensive drugs.

Poor blood pressure control in treated patients with hypertension is an important topic in the field of hypertension, and an unmet need for new therapeutic drugs remains. Soluble guanylate cyclase (sGC), a key signal transduction enzyme responsible for vasodilation, has attracted increasing interest as a therapeutic target in various cardiovascular diseases. Two different sGC agonists, sGC stimulators and activators, can increase its enzymatic activity in reduced and oxidized/apo forms, respectively. With some sGC agonists being already in clinical use, drugs in this category are expected to become new therapeutic agents for various conditions, including hypertension. In this review, we summarize the current knowledge on the antihypertensive effects of sGC agonists in various preclinical studies involving animal models of spontaneous hypertension, salt-sensitive hypertension, nitric oxide-deficient hypertension, renin-angiotensin-aldosterone system-dependent hypertension, malignant hypertension, metabolic syndrome, renoprival hypertension, renovascular hypertension, drug-induced hypertension, pregnancy hypertension, and treatment-resistant hypertension. Our compilation provides a comprehensive rationale for advancing the clinical development of sGC agonists for the treatment of hypertension.

Wall teichoic acid glycosylation of bovine-associated Staphylococcus aureus strains.

Staphylococcus aureus (S. aureus) is one of the major causes of bovine mastitis, a disease with detrimental effects on health and wellbeing. Current control measures are costly, laborious and not always effective in eradicating S. aureus. The cell wall-linked polysaccharide wall teichoic acid (WTA) is highly immunogenic in humans and is considered as a prospective vaccine antigen based on promising pre-clinical studies in animals. WTA consist of polymerized ribitol-phosphate backbone that is modified with N-acetylglucosamine (GlcNAc) moieties in different configurations by the glycosyltransferases TarS (β-1,4-GlcNAc), TarM (α-1,4-GlcNAc) and TarP (β-1,3-GlcNAc). This study aimed to characterize the presence and genetic variation in tarS, tarM and tarP in bovine-associated S. aureus strains and how this impacts WTA-glycoprofile. Bioinformatic analyses of a whole genome sequence database consisting of 1047 S. aureus, 10 S. schweitzeri, and 6 S. argenteus strains showed that over 99% of strains contained tarS, 34 % also contained tarM, while 5 % of the strains encoded tarP in addition to tarS. The distribution of WTA-glycosyltransferase genes was similar to what has been reported for human-associated S. aureus strains. Phenotypic analysis of WTA glycosylation by flow cytometry corroborated with tarS/tarM/tarP gene presence. The WTA glycoprofile was variable between bovine-associated strains and the levels and ratios of GlcNAcylation were affected by growth conditions. Interestingly, a divergent tarM allele was present in strains of clonal complexes (CC) 49 and the mastitis-associated CC151, but its function was similar to canonical tarM. In conclusion, we demonstrated that bovine-associated S. aureus strains show similar variation in WTA GlcNAc decoration as human S. aureus strains, despite the presence of a divergent tarM allele.

An Evaluation of the Safety of Intravenous Injections of the Natural Extracellular Hemoglobin M101 in Dogs and Monkeys.

Hemoglobin-based oxygen carriers have been developed to compensate the needs of blood for transfusions. Most of them were based on intracellular hemoglobin extracted from bovine or human blood, but unfortunately, this type of hemoglobin did not pass through the last steps of clinical trials. In this context, HEMARINA discovered a natural extracellular hemoglobin, possessing several advantages avoiding intracellular hemoglobin-related side effects. Many preclinical studies assessed the safety of M101 used in intravenous (IV) injection in rodents. To explore the safety of IV injections of M101 in large mammals, six dogs received each a single injection of liquid M101 according to a dose escalation with a 48 h follow-up. Then, two monkeys received multiple IV injections of the same dose of M101 every hour for seven hours. This study showed that single and multiple IV injections in dogs and monkeys did not cause clinical or histological lesions, nor did they induce immunological reactions. This makes M101 the best candidate to date for human use in emergency situations requiring blood and, in several diseases, causing hypoxia problems.