The Gut Microbiome, Metformin, and Aging.

Metformin has been extensively used for the treatment of type 2 diabetes, and it may also promote healthy aging. Despite its widespread use and versatility, metformin's mechanisms of action remain elusive. The gut typically harbors thousands of bacterial species, and as the concentration of metformin is much higher in the gut as compared to plasma, it is plausible that microbiome-drug-host interactions may influence the functions of metformin. Detrimental perturbations in the aging gut microbiome lead to the activation of the innate immune response concomitant with chronic low-grade inflammation. With the effectiveness of metformin in diabetes and antiaging varying among individuals, there is reason to believe that the gut microbiome plays a role in the efficacy of metformin. Metformin has been implicated in the promotion and maintenance of a healthy gut microbiome and reduces many age-related degenerative pathologies. Mechanistic understanding of metformin in the promotion of a healthy gut microbiome and aging will require a systems-level approach.

Antiretroviral drug dolutegravir induces inflammation at the mouse brain barriers.

Integrase strand transfer inhibitors (INSTIs) based antiretroviral therapy (ART) is currently used as first-line regimen to treat HIV infection. Despite its high efficacy and barrier to resistance, ART-associated neuropsychiatric adverse effects remain a major concern. Recent studies have identified a potential interaction between the INSTI, dolutegravir (DTG), and folate transport pathways at the placental barrier. We hypothesized that such interactions could also occur at the two major blood-brain interfaces: blood-cerebrospinal fluid barrier (BCSFB) and blood-brain barrier (BBB). To address this question, we evaluated the effect of two INSTIs, DTG and bictegravir (BTG), on folate transporters and receptor expression at the mouse BCSFB and the BBB in vitro, ex vivo and in vivo. We demonstrated that DTG but not BTG significantly downregulated the mRNA and/or protein expression of folate transporters (RFC/SLC19A1, PCFT/SLC46A1) in human and mouse BBB models in vitro, and mouse brain capillaries ex vivo. Our in vivo study further revealed a significant downregulation in Slc19a1 and Slc46a1 mRNA expression at the BCSFB and the BBB following a 14-day DTG oral treatment in C57BL/6 mice. However, despite the observed downregulatory effect of DTG in folate transporters/receptor at both brain barriers, a 14-day oral treatment of DTG-based ART did not significantly alter the brain folate level in animals. Interestingly, DTG treatment robustly elevated the mRNA and/or protein expression of pro-inflammatory cytokines and chemokines (Cxcl1, Cxcl2, Cxcl3, Il6, Il23, Il12) in primary cultures of mouse brain microvascular endothelial cells (BBB). DTG oral treatment also significantly upregulated proinflammatory cytokines and chemokine (Il6, Il1ß, Tnfα, Ccl2) at the BCSFB in mice. We additionally observed a downregulated mRNA expression of drug efflux transporters (Abcc1, Abcc4, and Abcb1a) and tight junction protein (Cldn3) at the CP isolated from mice treated with DTG. Despite the structural similarities, BTG only elicited minor effects on the markers of interest at both the BBB and BCSFB. In summary, our current data demonstrates that DTG but not BTG strongly induced inflammatory responses in a rodent BBB and BCSFB model. Together, these data provide valuable insights into the mechanism of DTG-induced brain toxicity, which may contribute to the pathogenesis of DTG-associated neuropsychiatric adverse effect.

Pharmacometabolomics in Drug Disposition, Toxicity and Precision Medicine.

The precision medicine initiative has driven a substantial change in the way scientists and health care practitioners think about diagnosing and treating disease. While it has long been recognized that drug response is determined by the intersection of genetic, environmental and disease factors, improvements in technology have afforded precision medicine guided dosing of drugs to improve efficacy and reduce toxicity. Pharmacometabolomics aims to evaluate small molecule metabolites in plasma and/or urine to help evaluate mechanisms that predict and/or reflect drug efficacy and toxicity. In this mini review, we provide an overview of pharmacometabolomic approaches and methodologies. Relevant examples where metabolomic techniques have been used to better understand drug efficacy and toxicity in major depressive disorder and cancer chemotherapy are discussed. In addition, the utility of metabolomics in drug development and understanding drug metabolism, transport and pharmacokinetics is reviewed. Pharmacometabolomic approaches can help understand factors mediating drug disposition, efficacy and toxicity. While important advancements in this area have been made, their remain several challenges that must be overcome before this approach can be fully implemented into clinical drug therapy. Significance Statement Pharmacometabolomics has emerged as an approach to identify metabolites that allow for implementation of precision medicine approaches to pharmacotherapy. This review article provides an overview pharmacometabolomics including highlights of important examples.

CML in the very elderly: the impact of comorbidities and TKI selection in a real-life multicenter study.

Tyrosine kinase inhibitors (TKIs) have greatly improved chronic myeloid leukemia (CML) treatments, with survival rates close to the general population. Yet, for the very elderly, robust data remains limited. This study focused on assessing comorbidities, treatment approaches, responses, and survival for elderly CML patients. Our study was conducted on 123 elderly (≥ 75 years) CML patients across four centers in Israel and Moffitt Cancer Center, USA. The median age at diagnosis was 79.1 years, with 44.7% being octogenarians. Comorbidities were very common; cardiovascular risk factors (60%), cardiovascular diseases (42%), with a median age-adjusted Charlson Comorbidity Index (aaCCI) of 5. Imatinib was the leading first-line therapy (69%), while the use of second-generation TKIs increased post-2010. Most patients achieved a major molecular response (MMR, 66.7%), and half achieved a deep molecular response (DMR, 50.4%). Over half (52.8%) of patients moved to second-line, and nearly a quarter (23.5%) to third-line treatments, primarily due to intolerance. Overall survival (OS) was notably longer in patients with an aaCCI score below 5, and in patients who attained DMR. Contrary to expectations, the Israeli cohort showed a shorter actual life expectancy than projected, suggesting a larger impact of CML on elderly survival. In summary, imatinib remains the main initial treatment, but second-generation TKIs are on the rise among elderly CML patients. Outcomes in elderly CML patients depend on comorbidities, TKI type, response, and age, underscoring the need for personalized therapy and additional research on TKI effectiveness and safety.

Dynamics of overdose and non-overdose mortality among people living with HIV amidst the illicit drug toxicity crisis in British Columbia.

We sought to characterize overdose and non-overdose mortality among PLWH amidst the illicit drug toxicity crisis in British Columbia, Canada. A population-based analysis of PLWH (age ≥19) in British Columbia accessing healthcare from April 1996 to March 2017 was conducted using data from the Seek and Treat for Optimal Prevention of HIV/AIDS (STOP HIV/AIDS) cohort linkage. Underlying causes of deaths were stratified into overdose and non-overdose causes. We compared (bivariate analysis) health-related characteristics and prescription history between PLWH died of overdose and non-overdose causes between April 2009 and March 2017. Among 9,180 PLWH, we observed 962 deaths (142 [14.7%] overdoses; 820 [85.2%] other causes). Compared to those who died from other causes, those who died of overdose were significantly younger (median age [Q, Q3]: 46 years [42, 52] vs. 54 years [48, 63]); had an indication of chronic pain (35.9% vs. 27.1%) and hepatitis C virus (64.8% vs. 50.4%), but fewer experienced hospitalization in the year before death. PLWH who died were most likely to be prescribed with opioids (>50%) and least likely with opioid agonist therapy (<10%) in a year before death. These findings highlight the syndemic of substance use, HCV, and chronic pain, and how the crisis is unqiuely impacting females and younger people.

Exploring Safety in Gender-Affirming Hormonal Treatments: An Observational Study on Adverse Drug Events Using the Food and Drug Administration Adverse Event Reporting System Database.

BACKGROUND: People with gender dysphoria are treated with hormone therapy for gender reassignment. The indication of this therapy was initially for the opposite sex, and information on potential adverse drug reaction (ADR) is lacking. OBJECTIVE: To describe ADR associated with gender transition medication in transgender individuals reported to the US Food and Drug Administration Adverse Event Reporting System (FAERS) database. METHODS: Data from the FAERS database up to June 2023 were examined, focusing on reports of gender transition medication use in the context of gender dysphoria. The ADRs were categorized using the Medical Dictionary for Regulatory Activities at both Preferred Term and System Organ Class (SOC) levels. Descriptive statistics summarized report counts, medication types, indications, and ADR severity. RESULTS: For individuals assigned female at birth undergoing gender transition to male (transgender men), 82 reports (230 ADRs) were analyzed, with an average age of 29.5 years. Transgender hormonal therapy was cited in 72% of reports, predominantly from the United States (67.1%). A striking 88% were categorized as serious ADRs, primarily SOC injury, poisoning, and procedural complications (26.5%), followed by psychiatric disorders (14.8%) and nervous system disorders (12.2%). Among those assigned sex male at birth transitioning to female (transgender women) (81 reports, 237 ADRs), mean age was 33.3 years, with 58% indicating use for gender dysphoria. A significant proportion (53.6%) were serious ADRs, primarily SOC: injury, poisoning, and procedural complications (26.6%). CONCLUSIONS AND RELEVANCE: The FAERS data reveal significant ADRs in transgender individuals using hormone therapy, sometimes unintended for their recipient gender. Population-level studies are crucial to enhance transgender health care. Spontaneous surveillance databases like FAERS illuminate off-label ADRs, urging health care providers to approach hormone therapies with informed caution.

Seizures in children undergoing stem cell transplantation.

BACKGROUND: Neurological complications (NCs) are of major concern following hematological stem cell transplantation (HSCT), most of which present with seizures. PROCEDURES: We performed a retrospective study (2002-2018) of patients undergoing HSCT in order to analyze the incidence and aetiologies related to seizures. RESULTS: Of 155 children undergoing HSCT, 27 (17.4%) developed seizures at some point in 2 years of follow-up. The most frequent etiologies were central nervous system (CNS) infection (n = 10), drug toxicity (n = 8), and vascular disease (n = 5). A statistically significant association was found between seizure and the HSCT type (lower risk for a related identical donor, p = .010), prophylactic or therapeutic mycophenolate use (p = .043 and .046, respectively), steroid use (p = .023), selective CD45RA+ depletion (p = .002), pre-engraftment syndrome (p = .007), and chronic graft-versus-host disease (GVHD) severity (p = .030). Seizures predicted evolution to life-threatening complications and admission to intensive care (p < .001) and higher mortality (p = .023). A statistically significant association was also found between seizures and sequelae in survivors (p = .029). Children who developed seizures had a higher risk of CNS infection and vascular disease (odds ratio 37.25 [95% CI: 7.45-186.05] and 12.95 [95% CI 2.24-74.80], respectively). CONCLUSIONS: Neurological complications highly impact survival and outcomes and need to be addressed when facing an HSCT procedure.

Elucidating the Mechanisms Underlying Interindividual Differences in the Onset of Adverse Drug Reactions.

Idiosyncratic drug toxicities (IDTs) pose a significant challenge; they are marked by life-threatening adverse reactions that emerge aftermarket release and are influenced by intricate genetic and environmental variations. Recent genome-wide association studies have highlighted a strong correlation between specific human leukocyte antigen (HLA) polymorphisms and IDT onset. This review provides an overview of current research on HLA-mediated drug toxicities. In the last six years, HLA-transgenic (Tg) mice have been instrumental in advancing our understanding of these underlying mechanisms, uncovering systemic immune reactions that replicate human drug-induced immune stimulation. Additionally, the potential role of immune tolerance in shaping individual differences in adverse effects highlights its relevance to the interplay between HLA polymorphisms and IDTs. Although HLA-Tg mice offer valuable insights into systemic immune reactions, further exploration is essential to decipher the intricate interactions that lead to organ-specific adverse effects, especially in organs such as the skin or liver. Navigating the intricate interplay of HLA, which may potentially trigger intracellular immune responses, this review emphasizes the need for a holistic approach that integrates findings from both animal models and molecular/cellular investigations. The overarching goal is to enhance our comprehensive understanding of HLA-mediated IDTs and identify factors shaping individual variations in drug reactions. This review aims to facilitate the development of strategies to prevent severe adverse effects, address existing knowledge gaps, and provide guidance for future research initiatives in the field of HLA-mediated IDTs.

Acetaminophen overdose causes a breach of the blood-bile barrier in mice but not in rats.

Acetaminophen (APAP) is known to cause a breach of the blood-bile barrier in mice that, via a mechanism called futile bile acid (BA) cycling, increases BA concentrations in hepatocytes above cytotoxic thresholds. Here, we compared this mechanism in mice and rats, because both species differ massively in their susceptibility to APAP and compared the results to available human data. Dose and time-dependent APAP experiments were performed in male C57BL6/N mice and Wistar rats. The time course of BA concentrations in liver tissue and in blood was analyzed by MALDI-MSI and LC-MS/MS. APAP and its derivatives were measured in the blood by LC-MS. APAP-induced liver damage was analyzed by histopathology, immunohistochemistry, and by clinical chemistry. In mice, a transient increase of BA in blood and in peri-central hepatocytes preceded hepatocyte death. The BA increase coincided with oxidative stress in liver tissue and a compromised morphology of bile canaliculi and immunohistochemically visualized tight junction proteins. Rats showed a reduced metabolic activation of APAP compared to mice. However, even at very high doses that caused cell death of hepatocytes, no increase of BA concentrations was observed neither in liver tissue nor in the blood. Correspondingly, no oxidative stress was detectable, and the morphology of bile canaliculi and tight junction proteins remained unaltered. In conclusion, different mechanisms cause cell death in rats and mice, whereby oxidative stress and a breach of the blood-bile barrier are seen only in mice. Since transient cholestasis also occurs in human patients with APAP overdose, mice are a clinically relevant species to study APAP hepatotoxicity but not rats.

Mining Real-World Big Data to Characterize Adverse Drug Reaction Quantitatively: Mixed Methods Study.

BACKGROUND: Adverse drug reactions (ADRs), which are the phenotypic manifestations of clinical drug toxicity in humans, are a major concern in precision clinical medicine. A comprehensive evaluation of ADRs is helpful for unbiased supervision of marketed drugs and for discovering new drugs with high success rates. OBJECTIVE: In current practice, drug safety evaluation is often oversimplified to the occurrence or nonoccurrence of ADRs. Given the limitations of current qualitative methods, there is an urgent need for a quantitative evaluation model to improve pharmacovigilance and the accurate assessment of drug safety. METHODS: In this study, we developed a mathematical model, namely the Adverse Drug Reaction Classification System (ADReCS) severity-grading model, for the quantitative characterization of ADR severity, a crucial feature for evaluating the impact of ADRs on human health. The model was constructed by mining millions of real-world historical adverse drug event reports. A new parameter called Severity_score was introduced to measure the severity of ADRs, and upper and lower score boundaries were determined for 5 severity grades. RESULTS: The ADReCS severity-grading model exhibited excellent consistency (99.22%) with the expert-grading system, the Common Terminology Criteria for Adverse Events. Hence, we graded the severity of 6277 standard ADRs for 129,407 drug-ADR pairs. Moreover, we calculated the occurrence rates of 6272 distinct ADRs for 127,763 drug-ADR pairs in large patient populations by mining real-world medication prescriptions. With the quantitative features, we demonstrated example applications in systematically elucidating ADR mechanisms and thereby discovered a list of drugs with improper dosages. CONCLUSIONS: In summary, this study represents the first comprehensive determination of both ADR severity grades and ADR frequencies. This endeavor establishes a strong foundation for future artificial intelligence applications in discovering new drugs with high efficacy and low toxicity. It also heralds a paradigm shift in clinical toxicity research, moving from qualitative description to quantitative evaluation.

Changes in harm reduction service providers professional quality of life during dual public health emergencies in Canada.

BACKGROUND: Harm reduction (HR) is a critical response to the pronounced toxicity deaths being experienced in Canada. HR providers report many benefits of their jobs, but also encounter chronic stress from structural inequities and exposure to trauma and death. This research study sought to quantify the emotional toll the toxicity emergency placed on HR providers (Cycle One; 2019). Study objectives were later expanded to determine the impact of the ongoing toxicity as well as the pandemic's impact on well-being (Cycle Two; 2021). METHODS: Standardized measures of job satisfaction, burnout, secondary traumatic stress, and vulnerability to grief were used in an online national survey. Open-ended questions addressed resources and supports. HR partners across Canada validated the findings and contributed to alternative interpretations and implications. RESULTS: 651 respondents in Cycle One and 1,360 in Cycle Two reported moderately high levels of job satisfaction; they reported finding great meaning in their work. Yet, mean levels of burnout and secondary traumatic stress were moderate, with the latter significantly increasing in Cycle Two. Reported vulnerability to grief was moderate but increased significantly during COVID. When available, supports lacked the quality necessary to respond to the complexities of HR workers' experiences, or an insufficient number of sessions were covered through benefits. Respondents shared that their professional quality of life was affected more by policy failures and gaps in the healthcare system than it was by the demands of their jobs. CONCLUSION: Both the benefits and the strain of providing harm reduction services cannot be underestimated. For HR providers, these impacts are compounded by the drug toxicity emergency, making the service gaps experienced by them all the more critical to address. Implications highlight the need for integration of HR into the healthcare system, sustainable and reliable funding, sufficient counselling supports, and equitable staffing models. Support for this essential workforce is critical to ensuring the well-being of themselves, the individuals they serve, and the health of the broader healthcare system.

Precision unveiled: Synergistic genomic landscapes in breast cancer-Integrating single-cell analysis and decoding drug toxicity for elite prognostication and tailored therapeutics.

BACKGROUND: Globally, breast cancer, with diverse subtypes and prognoses, necessitates tailored therapies for enhanced survival rates. A key focus is glutamine metabolism, governed by select genes. This study explored genes associated with T cells and linked them to glutamine metabolism to construct a prognostic staging index for breast cancer patients for more precise medical treatment. METHODS: Two frameworks, T-cell related genes (TRG) and glutamine metabolism (GM), stratified breast cancer patients. TRG analysis identified key genes via hdWGCNA and machine learning. T-cell communication and spatial transcriptomics emphasized TRG's clinical value. GM was defined using Cox analyses and the Lasso algorithm. Scores categorized patients as TRG_high+GM_high (HH), TRG_high+GM_low (HL), TRG_low+GM_high (LH), or TRG_low+GM_low (LL). Similarities between HL and LH birthed a "Mixed" class and the TRG_GM classifier. This classifier illuminated gene variations, immune profiles, mutations, and drug responses. RESULTS: Utilizing a composite of two distinct criteria, we devised a typification index termed TRG_GM classifier, which exhibited robust prognostic potential for breast cancer patients. Our analysis elucidated distinct immunological attributes across the classifiers. Moreover, by scrutinizing the genetic variations across groups, we illuminated their unique genetic profiles. Insights into drug sensitivity further underscored avenues for tailored therapeutic interventions. CONCLUSION: Utilizing TRG and GM, a robust TRG_GM classifier was developed, integrating clinical indicators to create an accurate predictive diagnostic map. Analysis of enrichment disparities, immune responses, and mutation patterns across different subtypes yields crucial subtype-specific characteristics essential for prognostic assessment, clinical decision-making, and personalized therapies. Further exploration is warranted into multiple fusions between metrics to uncover prognostic presentations across various dimensions.

Toxicity of the New Psychoactive Substance (NPS) Clephedrone (4-Chloromethcathinone, 4-CMC): Prediction of Toxicity Using In Silico Methods for Clinical and Forensic Purposes.

This study reports the first application of in silico methods to assess the toxicity of 4-chloromethcathinone (4-CMC), a novel psychoactive substance (NPS). Employing advanced toxicology in silico tools, it was possible to predict crucial aspects of the toxicological profile of 4-CMC, including acute toxicity (LD50), genotoxicity, cardiotoxicity, and its potential for endocrine disruption. The obtained results indicate significant acute toxicity with species-specific variability, moderate genotoxic potential suggesting the risk of DNA damage, and a notable cardiotoxicity risk associated with hERG channel inhibition. Endocrine disruption assessment revealed a low probability of 4-CMC interacting with estrogen receptor alpha (ER-α), suggesting minimal estrogenic activity. These insights, derived from in silico studies, are critical in advancing the understanding of 4-CMC properties in forensic and clinical toxicology. These initial toxicological findings provide a foundation for future research and aid in the formulation of risk assessment and management strategies in the context of the use and abuse of NPSs.

Mechanisms of chlorate toxicity and resistance in Pseudomonas aeruginosa.

Pseudomonas aeruginosa is an opportunistic bacterial pathogen that often encounters hypoxic/anoxic environments within the host, which increases its tolerance to many conventional antibiotics. Toward identifying novel treatments, we explored the therapeutic potential of chlorate, a pro-drug that kills hypoxic/anoxic, antibiotic-tolerant P. aeruginosa populations. While chlorate itself is relatively nontoxic, it is enzymatically reduced to the toxic oxidizing agent, chlorite, by hypoxically induced nitrate reductase. To better assess chlorate's therapeutic potential, we investigated mechanisms of chlorate toxicity and resistance in P. aeruginosa. We used transposon mutagenesis to identify genes that alter P. aeruginosa fitness during chlorate treatment, finding that methionine sulfoxide reductases (Msr), which repair oxidized methionine residues, support survival during chlorate stress. Chlorate treatment leads to proteome-wide methionine oxidation, which is exacerbated in a ∆msrA∆msrB strain. In response to chlorate, P. aeruginosa upregulates proteins involved in a wide range of functions, including metabolism, DNA replication/repair, protein repair, transcription, and translation, and these newly synthesized proteins are particularly vulnerable to methionine oxidation. The addition of exogenous methionine partially rescues P. aeruginosa survival during chlorate treatment, suggesting that widespread methionine oxidation contributes to death. Finally, we found that mutations that decrease nitrate reductase activity are a common mechanism of chlorate resistance.

Mitochondrial alterations in fatty liver diseases.

Fatty liver diseases can result from common metabolic diseases, as well as from xenobiotic exposure and excessive alcohol use, all of which have been shown to exert toxic effects on hepatic mitochondrial functionality and dynamics. Invasive or complex methodology limits large-scale investigations of mitochondria in human livers. Nevertheless, abnormal mitochondrial function, such as impaired fatty acid oxidation and oxidative phosphorylation, drives oxidative stress and has been identified as an important feature of human steatohepatitis. On the other hand, hepatic mitochondria can be flexible and adapt to the ambient metabolic condition to prevent triglyceride and lipotoxin accumulation in obesity. Experience from studies on xenobiotics has provided important insights into the regulation of hepatic mitochondria. Increasing awareness of the joint presence of metabolic disease-related (lipotoxic) and alcohol-related liver diseases further highlights the need to better understand their mutual interaction and potentiation in disease progression. Recent clinical studies have assessed the effects of diets or bariatric surgery on hepatic mitochondria, which are also evolving as an interesting therapeutic target in non-alcoholic fatty liver disease. This review summarises the current knowledge on hepatic mitochondria with a focus on fatty liver diseases linked to obesity, type 2 diabetes and xenobiotics.

9.4 T static magnetic field ameliorates imatinib mesylate-induced toxicity and depression in mice.

PURPOSE: 9.4 T magnetic resonance imaging (MRI) has been initially tested on healthy human volunteers, but its future application will benefit more from experiments with animal disease models. In the meantime, high static magnetic fields (SMFs) have been shown to improve mice mental health and have anti-tumor potentials. METHODS: We compared the anti-tumor effects of 9.4 T SMF with or without a commonly used chemotherapy drug imatinib mesylate on BALB/c (Nu/Nu) mice bearing gastrointestinal stromal tumor GIST-T1 cells. The body weight, food/water consumption, complete blood count, blood biochemistry, tumor weight, HE and Ki67 stains were examined. Locomotor activity and cognitive functions were also measured by four behavior tests, including open field, elevated plus maze, three-chamber and tail suspension tests. RESULTS: We found that the tumor growth was inhibited up to 62.88% when treated with 9.4 T SMF alone for 200 h. More importantly, 9.4 T SMF combined with 20 mg/kg imatinib mesylate can result in 92.75% tumor suppression, which is close to the anti-tumor effect of high dose (80 mg/kg) imatinib. However, 80 mg/kg imatinib caused severe side effects, including significantly reduced gain of body weight, abnormal liver function and depressive behaviors in mice. In contrast, 9.4 T SMF treatment significantly reduced these side effects, especially for the depressive behaviors. CONCLUSION: Our results demonstrate that 9.4 T SMF not only has anti-tumor effects on its own, but also could improve the anti-tumor effect of imatinib mesylate, reduce its toxicity and improve the mice mental health, which unraveled the great clinical potentials of high SMF in future applications.

Outcomes following heart or bilateral-lung transplantation from donors who died of drug toxicity in British Columbia, Canada.

INTRODUCTION: The illicit drug toxicity (overdose) crisis has worsened across Canada; between 2016 and 2021, more than 28,000 individuals have died of drug toxicity. Organ donation from persons who experience drug toxicity death (DTD) has increased in recent years. This study examines whether survival after heart or bilateral-lung transplantation differed by donor cause of death. METHODS: We studied transplant recipients in British Columbia who received heart (N = 110) or bilateral-lung (N = 223) transplantation from deceased donors aged 12-70 years between 2013 and 2019. Transplant recipient survival was compared by donor cause of death from drug toxicity or other. Five-year Kaplan-Meier estimates of survival and 3-year inverse probability treatment weighted Cox proportional hazards models were conducted. RESULTS: DTD donors made up 36% (40/110) of heart and 24% (54/223) of bilateral-lung transplantations. DTD donors were more likely to be young, white, and male. Unadjusted 5-year recipient survival was similar by donor cause of death (heart: 87% for DTD and 86% for non-DTD, p = .75; bilateral- lung: 80% for DTD and 76% for non-DTD, p = .65). Adjusted risk of mortality at 3-years post-transplant was similar between recipients of DTD and non-DTD donor heart (hazard ratio [HR]: .94, 95% confidence interval (CI): .22-4.07, p = .938) and bilateral-lung (HR: 1.06, 95% CI: .41-2.70, p = .908). CONCLUSION: Recipient survival after heart or bilateral-lung transplantation from DTD donors and non-DTD donors was similar. Donation from DTD donors is safe and should be considered more broadly to increase organ donation.

Artificial Intelligence in Drug Toxicity Prediction: Recent Advances, Challenges, and Future Perspectives.

Toxicity prediction is a critical step in the drug discovery process that helps identify and prioritize compounds with the greatest potential for safe and effective use in humans, while also reducing the risk of costly late-stage failures. It is estimated that over 30% of drug candidates are discarded owing to toxicity. Recently, artificial intelligence (AI) has been used to improve drug toxicity prediction as it provides more accurate and efficient methods for identifying the potentially toxic effects of new compounds before they are tested in human clinical trials, thus saving time and money. In this review, we present an overview of recent advances in AI-based drug toxicity prediction, including the use of various machine learning algorithms and deep learning architectures, of six major toxicity properties and Tox21 assay end points. Additionally, we provide a list of public data sources and useful toxicity prediction tools for the research community and highlight the challenges that must be addressed to enhance model performance. Finally, we discuss future perspectives for AI-based drug toxicity prediction. This review can aid researchers in understanding toxicity prediction and pave the way for new methods of drug discovery.

Fluorescent hiPSC-derived MYH6-mScarlet cardiomyocytes for real-time tracking, imaging, and cardiotoxicity assays.

Human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) hold great potential in the cardiovascular field for human disease modeling, drug development, and regenerative medicine. However, multiple hurdles still exist for the effective utilization of hiPSC-CMs as a human-based experimental platform that can be an alternative to the current animal models. To further expand their potential as a research tool and bridge the translational gap, we have generated a cardiac-specific hiPSC reporter line that differentiates into fluorescent CMs using CRISPR-Cas9 genome editing technology. The CMs illuminated with the mScarlet fluorescence enable their non-invasive continuous tracking and functional cellular phenotyping, offering a real-time 2D/3D imaging platform. Utilizing the reporter CMs, we developed an imaging-based cardiotoxicity screening system that can monitor distinct drug-induced structural toxicity and CM viability in real time. The reporter fluorescence enabled visualization of sarcomeric disarray and displayed a drug dose-dependent decrease in its fluorescence. The study also has demonstrated the reporter CMs as a biomaterial cytocompatibility analysis tool that can monitor dynamic cell behavior and maturity of hiPSC-CMs cultured in various biomaterial scaffolds. This versatile cardiac imaging tool that enables real time tracking and high-resolution imaging of CMs has significant potential in disease modeling, drug screening, and toxicology testing.

Clinical features and outcomes of patients admitted to the ICU for Cyclophosphamide-associated cardiac toxicity: a retrospective cohort.

PURPOSE: To describe the management and outcome of critically-ill patients with Cyclophosphamide (CY)-associated cardiac toxicity. METHODS: All patients admitted to the intensive care units (ICUs) of the Nantes and Rennes University Hospitals for a CY-associated cardiac toxicity between January 2015 and December 2020 were included. RESULTS: Of the thirty-four patients included in the study, twenty-four (70%) underwent allogeneic hematopoietic stem cell transplantation (HSCT), four (12%) autologous HSCT, and six (18%) chemotherapy for hematological malignancies. Acute pulmonary edema (65%), cardiac arrest (9%), and cardiac arrhythmia (6%) were the most common reasons for ICU admission. Patients were admitted to the ICU 6.5 (4-12) days after the intravenous administration of a median dose of CY of 100 [60-101] mg/Kg. Echocardiographic findings showed moderate to severe left ventricular systolic dysfunction (69%) and pericardial effusion (52%). Eighteen (53%) patients ultimately developed cardiogenic shock and required vasopressors (47%) and/or inotropes (18%). Invasive mechanical ventilation and renal replacement therapy were required in twenty (59%) and five (14%) patients, respectively. Sixteen (47%) patients died of whom 12 (35.3%) died from refractory cardiogenic shock. The left ventricular ejection fraction improved over time in most survivors with a median time until full recovery of 33 (12-62) days. Two (11%) patients had a persistent left ventricular dysfunction at 6 months. CONCLUSION: Refractory cardiogenic shock is the primary cause of death of patients with severe CY-related cardiotoxicity. Nonetheless, the cardiac function of most survivors recovered within a month.