Human & Experimental Toxicology

Ekholm-Kerppola, Heidi Maria; Löyttyniemi, Eliisa; Soukka, Tero; Rautava, Jaana

doi: 10.1177/09603271251388834pmid: 41127997

IntroductionBisphosphonates and denosumab are the most common antiresorptive drugs (ARs). ARs may cause medication-related osteonecrosis of the jaw (MRONJ) as a side effect, characterized by osteonecrosis and ulceration of the oral mucosa. The pathophysiology of MRONJ remains partly unclear and there is currently no consensus on its multietiological background. Immunomodulatory medications such as corticosteroids and antiestrogens may affect MRONJ onset.MethodsAn in vitro 3D cell culture model of gingival, keratinocytes, and fibroblasts were used to elucidate the pathogenesis of MRONJ. Cell cultures were exposed to ARs, followed by exposures to corticosteroids or antiestrogens. Morphology and proliferation were evaluated.ResultsAmong the ARs, alendronate caused the most negative cellular changes, while zoledronate only had a few effects. Denosumab caused more morphological cell atypia and proliferation than other ARs. The combined exposures of individual ARs with corticosteroids had some additional negative effects on gingival cells, whereas ARs with antiestrogen had few effects. The results are partly inconsistent, indicating that 3D cell culture experiments may not be the most suitable method for studying the effects of ARs.ConclusionThis study suggests that alendronate and denosumab affect gingival cell growth in a 3D cell culture model. These effects are smaller than reported in previous monolayer studies.

Eckhardt, Nina C.; Kadhim, Ali; Ceelen, Manon; Slev, Vina N.; Reijnders, Udo J. L.; Franssen, Eric J. F.

doi: 10.1177/09603271251387259pmid: 41123076

IntroductionAccurate determinations of the cause of death are crucial for public health, crime investigations, and social justice. In the Netherlands, cause-of-death determinations rely heavily on external examinations, which can miss substance-related deaths. This study investigates the added value of toxicological blood testing in the determination of the cause and manner of death by forensic physicians in the Netherlands.MethodsCollected blood samples of 642 decedents that were examined by a forensic physician in Amsterdam and surrounding regions underwent toxicological testing. Findings and concluding remarks from the external examination and toxicological testing were compared using descriptive statistics.ResultsBlood samples of 69% of cases tested positive for one or more pharmaceuticals, and 36% tested positive for illicit drugs and/or alcohol. In 55% of cases, toxicological testing revealed substances that were not indicated by the external examination. Its findings also prompted a revision of the initial cause and manner of death in 18 cases (3%).DiscussionKey limitations in this study include that not all detected substances were quantified and a verification bias of the included cases, which may have led to an underrepresentation of unsuspected detections. Nonetheless, despite the constraints of (routine) screening capabilities and the effects of post-mortem degradation and redistribution, this study presented the importance of toxicological blood testing within a multifaceted approach that combines toxicological findings with scene evidence, medical history and the external examination, which is essential for improving the accuracy of cause-of-death determinations by the forensic physician.

doi: 10.1177/09603271251390662pmid: 41162197

Morad, Basma B.; Salem, Ola M.; El-Esawy, Rasha Osama; Abd Elmonem, Fleur F.

doi: 10.1177/09603271251388830pmid: 41293964

IntroductionTesticular toxicity commonly manifests as impaired spermatogenesis and testicular atrophy. Bisphenol A (BPA), a commonly used organic plasticizer, negatively affects sperm parameters, hormonal levels, and fertility. Octreotide (OCT), a somatostatin analog, was originally used to treat acromegaly, carcinoid tumors, vasoactive intestinal peptide-secreting, and growth hormone-secreting tumors. OCT has demonstrated potential therapeutic properties beyond its traditional use in endocrine disorders. We hypothesized that OCT would attenuate BPA-induced testicular damage through its anti-inflammatory, anti-oxidant, and anti-autophagic properties. This study aimed to assess the mechanisms of BPA-induced testicular toxicity and evaluate the ameliorative effects of OCT.MethodsForty adult male Sprague Dawley (SD) rats were randomly assigned to four equal groups: group1: saline control, group2: dimethyl sulfoxide (DMSO) vehicle, group3: BPA-treated, and group4: BPA + OCT-treated. Treatments were administered for 4 weeks. Sperm count, testicular weight, serum testosterone, lactate dehydrogenase (LDH), alkaline phosphatase (ALP), total antioxidant capacity (TAC), testicular levels of malondialdehyde (MDA), tumor necrosis factor-alpha (TNFα), Beclin-1 (BECN-1), Microtubule-associated proteins 1A/1B light chain 3A (MAP1LC3A/LC3), mammalian target of rapamycin (M-TOR), histopathological examination, apoptotic index, and Johnson’s score were assessed.ResultsBPA administration significantly impaired spermatogenesis, reduced serum testosterone and TAC, and increased MDA, TNFα, and autophagy-related markers, along with histopathological damage of testis. Co-treatment with OCT mitigated these effects by improving sperm parameters, hormone levels, oxidative stress markers, inflammatory cytokines, and testicular histology.DiscussionThe findings suggest that OCT exerts a protective effect against BPA-induced testicular toxicity, through its anti-inflammatory, antioxidant, and autophagy-modulating properties. OCT may offer therapeutic potential in mitigating BPA-induced testicular toxicity.

Lashin, Heba Ibrahim; Sobeeh, Fatma Gaber; Sobh, Zahraa Khalifa

doi: 10.1177/09603271251387258pmid: 41059536

Li, Hongmin; Hong, Mengting; Liu, Yikun; Rahman, Shafiq ur; Li, Xuejuan; Zheng, Feng

doi: 10.1177/09603271251394706pmid: 41305921

IntroductionBardoxolone methyl (Bardo), a Kelch-like ECH-associated protein 1 (Keap1)–Nrf2 pathway activator, has demonstrated efficacy in slowing eGFR decline in diabetic kidney disease (DKD). However, its Phase 3 trial in stage 4 DKD was terminated owing to unexpected cardiovascular complications.MethodsTo explore the underlying mechanisms, the human cardiomyocyte cell line AC16 was subjected to various concentrations of Bardo. Nuclear translocation of Nrf2 and the expression of its downstream antioxidant factors, heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO1), were quantified. Cell injury was assessed using microscopy, crystal violet staining, and lactate dehydrogenase release assays. The research employed ferroptosis, apoptosis, and necrosis inhibitors to identify the mechanisms of cell death. Additional analyses included measurements of glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), reactive oxygen species (ROS), ferrous ions, and malondialdehyde (MDA), while mitochondrial ultrastructure was evaluated by transmission electron microscopy.ResultsBardo induced dose-dependent Nrf2 activation and increased AC16 cell death, which was attenuated by the ferroptosis inhibitor Ferrostatin-1 (Fer-1) but not by apoptosis or necrosis inhibitors. Mechanistically, Bardo suppressed SLC7A11 and GPX4 expression while elevating ROS, ferrous ions, and MDA levels. Ultrastructural analysis further revealed mitochondrial volume reduction, disrupted cristae, and increased membrane density.DiscussionThese findings establish that Bardo induces ferroptosis in cardiomyocytes, potentially explaining the cardiotoxic effects observed in clinical trials.

doi: 10.1177/09603271251389836pmid: 41392966

Du, Xiaoyan; Gao, Yanrong; Wu, Lihong; Cao, Jing; Wang, Suhua; Deng, Yang

doi: 10.1177/09603271251390993pmid: 41106813

IntroductionRare earth elements (REEs) are increasingly used across various industries, raising concerns regarding their potential health impacts. Exposure to REEs has been linked to systemic diseases affecting the respiratory, nervous, and immune systems. We aimed to explore the effects of REE exposure on neurological health.MethodsWe performed high-throughput sequencing to identify differentially expressed proteins in the plasma of REE-exposed patients compared to healthy individuals. Additionally, in the mouse model, we employed western blotting, quantitative real-time PCR (qRT-PCR), and kits to verify the association between REE exposure and brain damage.ResultsWe identified 144 differentially expressed proteins in the plasma of REE-exposed patients. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that these proteins were primarily related to synaptic functions and the glutamate synaptic pathway. A protein–protein interaction network constructed using the STRING database revealed strong interactions among brain injury-related proteins following REE exposure. In animal experiments, western blot analysis showed that exposure to Nd2O3 significantly increased protein levels of calcium channel voltage-dependent P/Q-type alpha 1A subunit, phospholipase A2 group IVA, and SH3 and multiple ankyrin repeat domains 1. qRT-PCR results confirmed increased expression of corresponding genes. Concurrently, elevated levels of malondialdehyde and nitric oxide and decreased total antioxidant capacity were observed.DiscussionOverall, our findings suggest that Nd2O3 exposure is closely associated with brain damage, and the glutamate synaptic pathway plays a significant role. Our study provides novel insights into the molecular mechanisms underlying Nd2O3-induced neurotoxicity.

Hîrjău, Andreea-Camelia; Marandiuc, Ilinca-Mihaela; Radu, Gabriel-Lucian

doi: 10.1177/09603271251389572pmid: 41297042

BackgroundAccurate and prompt assessment of malathion intoxication severity remains a significant clinical challenge, often hampered by reliance on single diagnostic markers. This exploratory case series investigated the combined utility of rapid butyrylcholinesterase (BChE) activity measurements and gas chromatography-tandem mass spectrometry (GC-MS/MS) for quantifying urinary malathion to enhance diagnostic precision.MethodsWe investigated three independent patients admitted with acute malathion intoxication. BChE activity was measured using both a point-of-care (POCT) device and a laboratory-based enzyme-multiplied immunoassay technique (EMIT). Urinary malathion was quantified using a validated GC-MS/MS method.ResultsMalathion exposure was confirmed in all patients via urinary analysis. Strong per-case positive correlations (r ranging from 0.905 to 0.996) were observed between the two BChE measurement methods, though Bland-Altman analysis revealed noteworthy discrepancies (mean bias of 10%, limits of agreement ranging from −20% to 40%). Critically, statistically significant inverse correlations (p < 0.05) were identified between urinary malathion concentrations and both BChE activity measurements, underscoring the dynamic relationship between exposure and enzymatic inhibition.ConclusionThese findings, derived from a small, exploratory case series, suggest the importance of an integrated diagnostic approach for malathion intoxication. This combined strategy may support improved assessment of severity and prognosis in individual cases, offering insights into the pesticide’s systemic impact and elimination kinetics, especially when exposure details are unclear. While rapid BChE tests are valuable for initial screening, their interpretation should occur within this multi-marker framework. The generalizability of these findings is limited by the small sample size, and no formal power calculation was performed.

Jarrar, Bashir; Almansour, Mansour; Al-Doaiss, Amin; Jarrar, Qais; Lee, Sun-Jun; Sewelam, Amal

doi: 10.1177/09603271251390978pmid: 41123097

BackgroundGold nanoparticles (Au NPs) have emerged as major contributors for innovative technologies and have been used extensively in various biomedical and industrial fields with little, if any, known about their neurotoxicity.ObjectiveThe current study aims to explore the nanotoxicity of Au NPs on the brain tissues.Materials and methodsTwo experimental groups, a control one and an Au NPs-treated group, each comprising 10 adult male Wistar albino rats, were used. Nanoparticle-treated rats received 28 intraperitoneal injections of 10 nm Au NPs at a daily dosage of 2 mg/kg.ResultsBrain tissue specimen for each rat under study was subjected to histological, immunohistochemical, and morphometric examination for alterations that might be induced by Au NPs exposure. Compared with control animals, brain tissue of rats treated with Au NPs exhibited neuronal shrinkage and pyknosis, perineuronal spacing, glial cell proliferation, vascular congestion, and neurons with lipofuscin pigmentation. Moreover, the hippocampus exhibited shrunken neurons, vascular congestion, and perivascular edema. Furthermore, the cerebellum showed degenerated Purkinje cells, cerebellar congestion, and perivascular spacing. In addition, the neuronal tissue demonstrated decreased autophagy, astrogliosis, and apoptosis presented by substantially decreased immunohistochemical protein expression of Beclin 1, increased expression of GFAP and caspase 3, respectively.ConclusionThe findings suggest that exposure to Au NPs has the potential to cause histological, immunohistochemical, and morphometric changes in brain tissue, which could impact the function of this vital organ. Further endeavors are necessary for more understanding of the potential risks of Au NPs to human health.