Archives of Toxicology

Alternaria toxins are naturally occurring food contaminants with limited and often inconsistent genotoxicity and mutagenicity data. Within the European Partnership for the Assessment of Risks from Chemicals (PARC), an OECD-aligned in vitro testing strategy was applied to fill existing data gaps and to characterize the genotoxic potential of major Alternaria toxins using high-purity test materials. Mutagenicity was assessed using bacterial reverse mutation test (OECD TG 471) and SOS/umu assay, while chromosomal damage was assessed using the in vitro micronucleus (MN) assay (OECD TG 487) in TK6 and HepG2 cells, complemented by fluorescence in situ hybridization (FISH) and {gamma}H2AX assay in HepaRG cells. Alternariol (AOH), alternariol monomethyl ether (AME), and altertoxin-I (ATX-I) showed clear mutagenicity in bacteria, whereas altenuene (ALT), tenuazonic acid (TeA), and tentoxin (TEN) were negative under the tested conditions. In mammalian cells, AOH, AME, and ATX-I induced MN formation in TK6 cells at concentrations [≥]5.5 {micro}M, [≥]2.5 {micro}M, and [≥]0.21 {micro}M, respectively, with FISH analysis supporting a clastogenic mode of action. In HepG2 cells, all tested toxins induced chromosomal damage, with effect threshold ranging from [≥]6.25 {micro}M (AOH) to [≥]50 {micro}M (TeA). {gamma}H2AX induction confirmed DNA damage for AOH and ATX-I, and at higher concentrations for TeA (1000 {micro}M). Overall, the data indicate clear in vitro genotoxic potential for AOH, AME, and ATX-I and provide evidence of chromosomal damage for ALT, TEN, and TeA, thereby reducing critical data gaps for hazard assessment.

Alternaria mycotoxins represent an emerging concern due to their frequent occurrence in food and feed. However, available toxicological data remain limited. Under the current EU regulatory framework, and in line with the EFSA/ECHA/JRC guidance for the identification of endocrine disruptors (EDs), assessment of endocrine activity relies on standardized assays performed according to OECD Test Guidelines (TGs) for the estrogen-, androgen- and steroidogenesis- (EAS) modalities. Within the framework of the European Partnership for the Assessment of Risks from Chemicals (PARC), standardized in vitro methods of regulatory relevance were performed for six chemically characterized Alternaria toxins, aiming to address current regulatory gaps on EAS-mediated activity. Alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), altertoxin-I (ATX-I), tentoxin (TEN) and altenuene (ALT) were assessed over a broad concentration range, from 0.001 up to 60 M, depending on cytotoxicity and solubility profile of each compound. Our findings indicate estrogenic activity for AOH (PC50: 3.9 - 4.6 {micro}M) and AME (PC50: 5.2 - 8.5 {micro}M) in the estrogen receptor transactivation assay (OECD TG 455), as well as an anti-estrogenic activity for ATX-I (IC30: 0.27 - 0.37 {micro}M). Minimal positive responses were observed at high concentrations for AOH (from the dose of 3 {micro}M) and for AME (from the dose of 10 {micro}M) in the agonistic part of the androgen receptor transactivation assay (OECD TG 458), which may also reflect glucocorticoid receptor activation. No effects on estradiol or testosterone production were observed for any of the tested Alternaria compounds in the steroidogenesis assay (OECD TG 456).

Tenuazonic acid (TeA) is an emerging Alternaria mycotoxin frequently detected in food and feed commodities, raising concerns about its toxicological relevance. Chronic oral exposure to TeA has been reported to induce dysplastic alterations in the esophageal mucosa of mice, while human biomonitoring data indicate an association between TeA exposure and esophageal cancer, although a causal relationship has not yet been established. At a mechanistic level, the effects of TeA in esophageal cells remain poorly characterized. Therefore, this study investigated the impact of TeA on cytotoxicity, oxidative stress, DNA damage, mitochondrial homeostasis, cell-cycle distribution and transcriptomic stress responses in human esophageal KYSE-510 cells. TeA induced a concentration-dependent reduction in metabolic activity and total protein content after 24 h exposure to 0.1-100 M. Significant cytotoxicity was measured starting from 20 M. At sub-cytotoxic concentrations, TeA triggered rapid ROS formation within 5-30 min exposure and induced formamidopyrimidine-DNA glycosylase (FPG) sensitive DNA damage after 1 h exposure (5-7.5 M), indicating oxidative DNA lesions. In addition, TeA altered mitochondrial morphology after 4 h exposure at 7.5 M, manifested by shrinkage of the mitochondrial network area and perinuclear redistribution, while mitochondrial respiration showed only a non-significant tendency towards reduced respiratory capacity. RNA sequencing after 6 h exposure to 10 M TeA revealed oxidative stress-associated transcriptional changes, impaired antioxidant and stress-adaptive responses, and p53-associated stress signaling. Furthermore, TeA induced significant G2/M phase accumulation after 24 h exposure to 1-10 M.

Introduction: Pediatric nicotine exposures remain an important and preventable public health issue, particularly with the rapid expansion of electronic nicotine delivery systems. This study compared demographic characteristics, exposure circumstances, and clinical outcomes between pediatric cases involving nicotine devices and bottled liquids reported to U.S. poison centers. Method: This retrospective cohort study analyzed National Poison Data System cases from 2011-2022 involving children aged less than 6 years exposed to nicotine devices or bottled liquids. Analyses were limited to cases with definitive medical outcomes. The primary outcome was defined as a moderate or major clinical effect or death. Odds ratios with 95% confidence intervals were calculated, with a secondary analysis restricted to route-concordant exposures. Results: The final cohort included 15,497 cases: 10,168 device exposures and 5,329 liquid exposures. Demographic characteristics were similar between groups. Device exposures more frequently involved inhalation, while ingestion predominated overall. Clinical effects were typically mild and transient, with vomiting and coughing most commonly reported. The primary outcome occurred in 1.9% of device cases and 2.0% of liquid cases (OR = 1.05; 95% CI 0.82-1.34). A secondary analysis restricted to inhalation-only device exposures and ingestion-only liquid exposures similarly found no significant difference in clinically important outcomes (OR = 1.38; 95% CI 0.92-2.12). Two deaths occurred, one in each group. Conclusion: These findings suggest that, despite differences in formulation and route of exposure, nicotine devices and bottled liquids produce broadly similar clinical toxicity profiles in young children. Prevention strategies should address all household nicotine products rather than focusing on specific delivery systems.

Tenuazonic acid (TeA) is one of the most frequently detected Alternaria mycotoxins in contaminated food. Despite its frequent occurrence, its immunomodulatory effects remain insufficiently characterized. Therefore, the present study investigated the impact of TeA on inflammatory signaling and cytokine regulation in monocytes and intestinal epithelial cell (IEC) models. NF-{kappa}B activity was assessed using a reporter gene assay in THP1-Lucia monocytes, while cytokine mRNA expression and protein secretion were quantified in Caco-2 and HCEC-1CT cells by qRT-PCR and ELISA, respectively. In THP-1 monocytes, TeA significantly suppressed lipopolysaccharide (LPS)-induced NF-{kappa}B activation in a concentration-dependent manner starting at 25 M, while cytotoxicity occurred only at concentrations [≥]100 M. In HCEC-1CT and differentiated Caco-2 cells, TeA increased IL-6, IL-8, and TNF- mRNA levels at non-cytotoxic concentrations ([≥]10 M). In Caco-2 cells, these transcriptional changes were accompanied by increased cytokine secretion, whereas HCEC-1CT cells showed only partial effects on the protein level after short-term exposure. Following prolonged incubation, TNF- secretion was increased and IL-6 and IL-8 secretion were slightly reduced. IL-10 remained unaffected under all conditions. Overall, TeA exerted cell type-dependent immunomodulatory effects characterized by immunoinhibitory activity in monocytes and pro-inflammatory responses in IECs, highlighting the complex immunotoxic potential of this Alternaria mycotoxin.

Key PointsO_LIPerfused human kidney MPS revealed CsA-associated sublethal tubular stress that was not detected by conventional 2D viability assays or by KIM-1 release in 3D MPS. C_LIO_LIAt matched exposure, VCS preserved mitochondria and activated ER chaperones and iron detoxification, with no p21 arrest compared to CsA. C_LIO_LIMechanistic separation supports VCSs nephroprotection potential and early mechanism-based biomarkers to guide CNI choice. C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/737071v1_ufig1.gif" ALT="Figure 1"> View larger version (46K): org.highwire.dtl.DTLVardef@e5e01dorg.highwire.dtl.DTLVardef@1dc9167org.highwire.dtl.DTLVardef@1ce22f8org.highwire.dtl.DTLVardef@5a053a_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical AbstractC_FLOATNO C_FIG BackgroundCalcineurin inhibitors (CNIs) are indispensable for transplantation immunosuppression, yet cyclosporine A (CsA) produces renal toxicity. Voclosporin (VCS), a CsA analog, is proposed to be less nephrotoxic, but mechanisms remain unclear. MethodsPrimary human proximal tubule epithelial cells (PTECs) were exposed to CsA or VCS in 2D monolayers and perfused 3D kidney microphysiological system (MPS). Viability was assessed in 2D cultures by MTS, mitochondrial membrane potential ({Delta}{Psi}m) by TMRM flow cytometry, and soluble injury and inflammatory biomarkers in MPS effluents by ELISA and MSD multiplex assays. RNA sequencing of 3D-cultured PTECs was used to identify differentially expressed genes and pathways. ResultsIn 2D PTECs, neither drug reduced viability. In 3D MPS effluents, KIM-1 did not distinguish CsA from VCS, whereas the MSD biomarker panel showed larger aggregate deviation with CsA. Confocal tomography showed CsA-associated mitochondrial fragmentation, whereas VCS preserved reticular mitochondrial architecture. TMRM flow cytometry showed a treatment-dependent difference in TMRM-positive cells, with VCS yielding the highest TMRM-positive fraction and exceeding CsA, supporting preservation of {Delta}{Psi}m relative to CsA. RNA-seq identified 1188 CsA-specific and 185 VCS-specific differentially expressed genes, with 304 shared. Pathway analysis indicated CsA enrichment of unfolded protein response (UPR) and endoplasmic reticulum (ER) stress, p21-associated G2/M checkpoint arrest, and transcriptional signatures consistent with ferroptosis priming, while VCS mainly induced ER chaperone and ER-associated degradation gene programs without activating canonical UPR sensors and showed limited cell-cycle suppression. ConclusionsA physiologically relevant 3D kidney MPS revealed sublethal tubular stress from CsA that is masked in 2D culture, including mitochondrial depolarization, proteostatic stress, and ferroptosis priming. At matched exposure, VCS preserved mitochondrial function and proteostasis while eliciting a narrower, adaptive ER quality control response. These data support VCS as a nephron-sparing immunosuppressant and 3D MPS as a mechanism-based platform for evaluating renal safety of drugs and nominating early sub-lethal tubular injury biomarkers.

Evidence of negative health and environmental effects of glyphosate-based herbicides (GBHs) has led to marketing of glyphosate-free formulations. A frequent glyphosate replacement is pelargonic acid, which is rapidly degraded, leading to claims of greater safety and less environmentally damaging than GBHs. However, toxicity of commercial pelargonic acid formulations containing several co-formulants have not been determined. Using Roundup NL, a representative pelargonic acid-based herbicide, we undertook tissue culture cell assays measuring viability, plasma membrane integrity, DNA damage, and activation of stress-response pathways. In human hepatoma HepG2 cells, Roundup NL was more cytotoxic than pelargonic acid, and more toxic than the GBH Roundup ProBio and glyphosate as shown by reduced viability underpinned by plasma membrane damage. Pelargonic acid and Roundup NL did not induce oxidative stress. However, comet assays revealed that pelargonic acid but not Roundup NL caused a modest but significant increase in DNA damage at sub-cytotoxic concentrations. The murine embryonic stem cell-based ToxTracker system confirmed Roundup NL as not directly genotoxic but triggered oxidative stress and protein damage (ER stress, impaired proteostasis) indicating cell and assay dependency of oxidative stress pathway activation. Our results suggest that exposure to pelargonic acid-based herbicides constitutes a health hazard and that co-formulants present in Roundup NL contribute substantially to its overall toxicity.

Study objective. Some acetaminophen-overdose patients develop hepatotoxicity despite acetylcysteine treatment. Established tools struggle to prospectively identify this cohort. We developed a model using only routine admission biomarkers to identify acetylcysteine-treated patients at highest risk, and compared it with the current benchmark, the alanine aminotransferase x acetaminophen product (ALTxAPAP). Methods. Retrospective cohort of all acetaminophen overdose admissions (ICD-10 T39.1) to three UK hospitals (2008-2024) with alanine aminotransferase (ALT) >1000U/L at admission. We fitted elastic-net logistic models stratified by presentation ALT. The outcome was peak ALT >1,000U/L. Performance was assessed on a 25% held-out test set and benchmarked against ALTxAPAP. Results. Of 4,705 admissions, 119 (2.5%) developed hepatotoxicity. The model used seven routine blood tests, four per stratum: acetaminophen, sodium, potassium and lymphocyte count where presentation ALT was <50U/L; ALT, bilirubin, alkaline phosphatase and lymphocyte count where it was 51-1,000U/L. In the test set (n=1,175) it achieved an area under the curve of 0.93 (95% CI 0.89-0.97) versus 0.82 (0.72-0.91) for ALTxAPAP (paired difference 0.11; 95% CI 0.01-0.22; p=0.03), with higher specificity and a higher positive likelihood ratio at every matched sensitivity. Matched to current ALTxAPAP >1,500 practice (sensitivity 89.7%), specificity was 82.5% versus 62.6% and the positive likelihood ratio 5.1 versus 2.4, more than halving false-positive escalations (171 versus 365 per 1,000 patients). Conclusion. A stratified model using only routine admission biomarkers identifies acetylcysteine-treated patients at highest residual hepatotoxicity risk, outperforming the ALTxAPAP rule across decision thresholds, supporting selection for intensified therapy.

Per- and polyfluoroalkyl substances (PFAS) are persistent toxicants with immunological, metabolic and epithelial effects, but their relevance to inflammatory skin disease remains unclear. We developed a computational toxicology framework to test whether perfluoroalkyl sulfonate programs, especially perfluorooctanesulfonic acid (PFOS) and perfluorohexanesulfonic acid (PFHxS), converge with psoriasis-associated keratinocyte inflammation. Exposure transcriptomes were derived from GSE236956, in which human embryonic stem cell-derived epithelial-lineage models were exposed to 10 M PFAS for 8-16 days. Six PFAS were prioritized using descriptors, Tanimoto similarity, toxicology evidence, adverse outcome pathway (AOP)-like key events, exposure differentially expressed gene burden and read-across support. PFAS signatures were integrated with psoriasis bulk transcriptomes, single-cell RNA sequencing, keratinocyte-state mapping, regulator and communication inference, spatial transcriptomics and token-aware Geneformer-compatible virtual perturbation. PFOS ranked highest in integrated prioritization, followed by PFHxS and perfluorooctanoic acid. PFHxS produced a smaller but directionally informative signature within a PFOS-dominant perfluoroalkyl sulfonate footprint. The shared PFOS and PFHxS program converged with psoriasis through inflammatory keratinocyte, epidermal-stress, cytoskeletal and lipid-related modules. Single-cell and spatial analyses localized the program to activated keratinocytes and inflammatory epidermal niches, with strong spatial co-localization with inflammatory keratinocyte and epidermal stress scores. Virtual perturbation prioritized S100A9, S100A8, KRT16, IL36G, CCL20, CXCL8, FABP5, KRT17, FOS, JUN and NFKBIZ as candidate effectors. These findings support an exposure-informed, experimentally testable hypothesis linking persistent perfluoroalkyl sulfonate programs to keratinocyte inflammatory niches in psoriasis.

Animal cell-cultured ingredients are entering the EU and UK pet food markets under frameworks that do not require pre-market, ingredient-level safety assessments, creating an ethical need for transparent safety disclosure. We present the first public safety dossier for this sector, describing the proprietary mouse embryonic stem cell line PE25 and its derived, non-viable cellular and conditioned media ingredient produced in food and feed-grade media. PE25 characterization confirmed Mus musculus identity, sterility, absence of mycoplasma and replication-competent retroviruses, and stable growth. Doxorubicin-induced p53 stress testing, CD44/BMI1 profiling, and soft agar assays showed no cancer-like traits and a non-tumorigenic profile; the final ingredient contains no viable cells. Independent OECD TG 471 and 487 assays confirmed non-genotoxicity. Heavy metals, biogenic amines, solvents, and chemical residues were below regulatory limits. Given process variability, we recommend case-by-case safety evaluation and propose this dossier as a model for responsible commercialization.

An acetaminophen (APAP) overdose is the leading cause of drug-induced hepatotoxicity and acute liver failure (ALF) in the United States. While N-acetylcysteine (NAC), is highly effective when administered early after an overdose, its efficacy decreases with delayed administration. Since most patients present late to the clinic, there is an urgent need for novel late-acting therapeutic options to prevent progression to ALF. We previously demonstrated the benefit of delayed activation of the Adenosine A2B Receptor (A2BAR) in attenuating APAP-induced hepatotoxicity and this study focuses on its effects on liver recovery after injury. Fasted male C57BL/6J mice were treated with 300 mg/kg APAP, followed by activation of A2BAR 6 or 9 h later and sacrifice 24, 48 or 72 h post-APAP with evaluation of liver injury, the innate immune response and liver regeneration. Delayed activation of A2BAR significantly enhanced liver recovery, with accelerated repopulation of the liver by Kupffer cells, increased macrophage migration to the necrotic areas and their faster resolution. A2BAR activation also upregulated lipid metabolism related genes in non-parenchymal cells and cell proliferation and metabolism genes in hepatocytes. Remarkably, genes such as Cidec and Plin2, crucial for lipid droplet formation, were upregulated, indicating that A2ABR activation enhances lipid metabolism which plays a key role in providing energy for liver regeneration. Overall, these findings highlight the potential of A2BAR activation not only in protecting against liver injury, but also in promoting and accelerating liver regeneration by modulating the innate immune responses and metabolic pathways.

Depleted uranium (DU) is an environmental contaminant with a 30 g/L (ppb; parts per billion) EPA maximum contaminant level (MCL) for drinking water. The mining of uranium and use of DU in modern weapons underly human exposure that disproportionally impacts military and tribal communities in the United States. Uranium's radiotoxic characteristics are understood, but its chemical hazards much less so. In zebrafish (Danio rerio) and human cell cultures we test the hypothesis that exposure to DU negatively impacts cellular function and development through disruption of mitochondrial metabolism. Using a novel shrapnel model with TEM/SEM+EDS, we showed uranium microparticles caused proximity-dependent mitochondrial disruption. In waterborne exposure paradigms, larval movement was reduced and hatching delayed as a result of reduced movement and not enzyme deficiencies in response to 18 ppb DU, below the MCL. Increased DNA damage accumulation was detected in exposed larva and cells. DNA-damage quantitative PCR of DU-exposed larvae showed increased damage in the ahr1 locus (nuclear gene) and decreased mitochondrial DNA (mtDNA) copy number, but mtDNA damage levels varied across experiments. Mitochondrial function was assessed using a resazurin-based assay in the presence and absence of antioxidants and showed diminished cytoplasmic reductive capacity. DU exposure alone did not enrich antioxidant gene expression, contrasting with arsenic exposure, a known ROS-inducer and Nrf2-activator. Sulforaphane (SFN), a potent Nrf2-activator, did not blunt the effects of DU exposure, despite activation of antioxidant response element (ARE) genes (gstp and gss), but did blunt the effects of arsenic exposure. The most enriched transcript in DU-exposed larvae coded for slingshot protein phosphatase (ssh), further exploration revealed ssh1b as the zebrafish-specific ortholog activated in response to DU, and inhibition using an identified SSH1 inhibitor, Sennoside A, partially rescued the metabolic and hatching defects observed. Our data points to a cytotoxic mechanism in which DU disrupts mitochondrial function through ssh1b enrichment that impairs normal mitophagy, leading to decreased cellular reductive potential independent of either ROS production or ARE-activation. Our results suggest that health impacts from DU exposure may be directly linked to impaired mitochondrial functions.

Retinal and choroidal vascular diseases are major causes of vision loss that require frequent intravitreal anti-VEGF therapy. Anti-angiogenic peptide AXT107 demonstrated efficacy in preclinical studies and was advanced to the clinical stage. To provide for sustained delivery of the peptide and avoid complications with intravitreal injection, we evaluated suprachoroidal delivery of AXT107 microparticles (MP-AXT107). The original, soluble AXT107 formulation was ineffective at inhibiting laser-induced choroidal neovascularization (CNV) in our rat model and was consequently reformulated as microparticles. MP-AXT107 demonstrated high peptide incorporation efficiency, reproducible morphology, and physical and chemical stability for at least 9 months under refrigerated storage. In the rat CNV model, suprachoroidal MP-AXT107 significantly reduced neovascular area by approximately 60% relative to vehicle controls. Safety and durability were evaluated in a 9-month GLP toxicology study in Gottingen minipigs following a single suprachoroidal injection of vehicle or MP-AXT107 (0.125-1.25 mg/eye). Transient increases in IOP and mild ocular inflammatory findings were observed immediately following administration but resolved rapidly without lasting effects. No treatment-related adverse ocular findings were observed during the remainder of the study, and the highest tested dose (1.25 mg/eye) was established as the no-observed-adverse-effect level. Bioanalysis at study completion demonstrated persistent AXT107 localization primarily within choroid/RPE and scleral tissues, with no signs of systemic exposure. Collectively, these findings demonstrate that suprachoroidal delivery of MP-AXT107 enables sustained anti-angiogenic activity with favorable ocular safety and prolonged tissue retention, supporting further clinical development as a durable therapy for retinal and choroidal vascular diseases.

Alternaria fungi produce various structurally diverse mycotoxins, several of which exhibit immunomodulatory properties. Among these, alternariol monomethyl ether (AME), alternariol (AOH), alterperylenol (ALTP), altertoxin I (ATX-I), and altersetin (AST) have been reported to suppress lipopolysaccharide (LPS)-induced inflammatory responses. However, the precise molecular mechanisms underlying these effects remain unclear. The present study aimed to elucidate how these selected Alternaria mycotoxins (0.1-50 M) target the NF-{kappa}B signaling pathway in THP-1 monocytes. Key components of the NF-{kappa}B cascade were analyzed by immunofluorescence microscopy, Western blotting and qRT-PCR. Nuclear translocation of NF-{kappa}B p65 and its phosphorylated form (p- NF-{kappa}B p65) was assessed by Western blot, while cytokine responses were determined at transcript (qRT-PCR) and protein (ELISA) levels. Moreover, in silico docking analyses were performed to investigate potential interactions of the toxins with IKK{beta}, and receptor-mediated crosstalk was studied using the glucocorticoid receptor (GR) antagonist RU486. Co-treatment with RU486 attenuated the immunosuppressive effects of 1 and 5 M AOH, indicating partial involvement of GR-dependent mechanisms. AME, AOH, ALTP, ATX-I, and AST increased total I{kappa}B levels while reducing its phosphorylated form. Additionally, AST and ALTP decreased the protein levels of Toll-like receptor 4 (TLR4), the I{kappa}B kinase (IKK) complex, NF-{kappa}B p65, and p- NF-{kappa}B p65. While AOH (5 M) and AST (25 M) reduced nuclear translocation of p65 and p-p65, ALTP (2 M) enhanced nuclear localization despite decreasing cytokine expression. Together, these findings suggest toxin-specific interference at multiple regulatory levels of NF-{kappa}B signaling and provide novel mechanistic insight into the immunomodulatory effects of Alternaria mycotoxins.

The time of day of UV exposure impacts both erythema and cancer development. To investigate whether UV-relevant clock-controlled gene expression can be modulated pharmacologically, we treated human skin explants with a combination of a cryptochoursome inhibitor and REV-ERB antagonist and then examined changes in gene expression of a limited number of core clock and clock-regulated genes. mRNA levels of both the DNA repair factor XPA and cell cycle checkpoint kinase WEE1 were found to be significantly increased by treatment. This pilot study suggests that clock-controlled gene expression can be altered pharmacologically to possibly alter skin responses to UV radiation.

Background: Natural essential oils exhibit antimicrobial and wound-healing properties, but their therapeutic application is limited by poor water solubility, volatility, and instability. This study developed and characterized a nanoemulsion of Ocimum gratissimum essential oil (OGNe) and evaluated its physicochemical properties, dermal safety, antibacterial activity, and wound-healing potential. Methods: Essential oil was obtained by hydrodistillation and formulated into nanoemulsions by high-speed stirring emulsification. Physicochemical properties, including pH, droplet size, polydispersity index, and storage stability, were determined. Acute dermal toxicity was assessed in Wistar rats following OECD Test Guideline 402. Antibacterial activity was evaluated using broth microdilution, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill assays. Wound-healing efficacy was investigated using an excision wound model over 21 days using distilled water and trolamine serving as controls. Results: OGNe exhibited a stable milky appearance, near-neutral pH, and droplet sizes ranging from 26 to 224 nm. No signs of dermal toxicity or behavioral abnormalities were observed after topical administration. The nanoemulsion showed selective antibacterial activity, with the highest susceptibility against Acinetobacter baumannii (MIC = 1.125 L/mL), whereas Escherichia coli remained resistant. Time-kill assays demonstrated concentration-dependent bacteriostatic activity. In vivo, OGNe significantly accelerated wound contraction from day 3 onward (p < 0.0001), achieving healing rates comparable to or exceeding those of trolamine during the inflammatory and proliferative phases. Conclusion: Ocimum gratissimum nanoemulsions represent stable, biocompatible topical formulations that combine selective antibacterial activity with enhanced wound healing, supporting their potential as phytopharmaceutical nanoformulations for the management of acute skin wounds.

High concentrations of steroidal hormone compounds are a growing source of concern for environmental pollution in aquatic ecosystems. In this study, we examine the effects of two estrogenic compounds (estriol and 17-ethinylestradiol) on fitness traits in the aquatic microcrustacean, Daphnia magna, a key bioindicator species for toxicology studies. The impacts were compared of two forms representing a natural and synthetic estrogenic compound. Growth and reproduction traits were assayed by exposing Daphnia to each estrogen type at four concentrations reflecting potential environmental exposure conditions up to acute toxicity levels (ranging from 0.1 - 50 {micro}g/L). Assaying the effects at a variety of concentrations is important given that it is known that hormone exposures can often result in non-monotonic responses. Both forms of estrogen impact a subset of the traits assessed, in some cases leading to beneficial changes and others causing harm. Estriol, the naturally-occurring estrogen, and EE2, the synthetic version, at high doses shift fitness traits in opposite directions such as adult growth rate as do at low doses for fecundity. In conclusion, our results support the need to assay a wide array of traits using multiple forms of steroidal hormones at a range of doses in order to assess non-monotonic patterns and their impact on an organismal fitness. In particular, assays that extend beyond the conventional measurements of lethality during acute exposure windows will be essential for understanding the impact of increased levels of hormone pollution on aquatic organisms and ecosystem health.

Immune cell engagers (ICE) such as bispecific antibodies (bsAbs), within an immunological synapse, bind and link CD3 on a T cell to a target antigen (TAA) on a cancer cell, forming a trimer (CD3:bsAb:TAA complex). With sufficient trimer numbers within the synapse, the T cell can become activated and promote cancer cell killing. Elranatamab, a CD3-bispecific antibody for multiple myeloma, has received FDA and EMA filing acceptance (August 2023 and December 2023, respectively) adding to a growing list of bsAbs that are treating patients. In the drug development stages of ICE bsAbs, mechanistic modeling approaches are often used to attain a greater quantitative understanding of the modality, preclinically, and provide human pharmacokinetic and efficacious dose predictions to aide in Phase 1 trial design. To date, the majority of ordinary differential equation (ODE) trimer models treat the tumor compartment as well-mixed and trimer formation is governed by a bulk population reaction not accounting for individual synapses. This lack of discrimination can lead to imprecise analysis when analyzing results across E:T ratios using metrics like trimers per T cell or trimers per target cell. To this end we developed an ODE trimer model based on single-synapse complexes (one target cell/one immune cell) with 2D cross-linking trimer formation. We show computationally that the number of trimers per synapse is invariant to the value of the E:T ratio for a given free bsAb concentration, a property that cannot be captured by non-synapse models. A simple demonstration of this discrepancy using the well-known Betts trimer model is presented. We then apply the Betts trimer model coupled to a tumor growth inhibition (TGI) module to show that our synapse-based trimer model is easy to substitute in to model TGI, including the addition of a trimer-per-synapse activation threshold function for cell killing. Overall, our model attempts to balance mechanistic fidelity while limiting the complexity of the model.

The main olfactory epithelium (MOE) is the primary site of olfaction and consists of multiple cell types including olfactory sensory neurons (OSNs), sustentacular cells, and immune cells. Neuroimmune interactions in epithelial tissues are critical in maintaining tissue function, but how OSNs and immune cells interact in the MOE in healthy and diseased states is largely unknown. Cellular responses in the MOE determine how and whether OSNs maintain olfactory function and are repaired or replenished following inflammatory environmental exposures. We hypothesized that acute nasal aeroallergen exposure alters immune cell function in the MOE to elicit a neuroprotective response, thereby preserving OSN function. We developed an environmental aeroallergen exposure consisting of one week of daily intranasal house dust mite extract (HDM) instillations. Spectral flow cytometry indicated only subtle changes in resident immune cells proportions and phenotypes in the MOE. Immunohistochemical evaluation did not reveal extensive changes in immune cell distribution in the sensory epithelium or lamina propria, but instead we observed increases in axonal olfactory marker protein (OMP) expression in the lamina propria, where resident immune cells are most abundant. To evaluate the effects of HDM exposure on OSN function, we performed live ex vivo Ca2+ imaging of MOEs from HDM- and sham-exposed transgenic mice using objective-coupled planar illumination (OCPI) microscopy. OSN responses to multiple odorants revealed increased chemosensory sensitivity and decreased across-trial adaptation in HDM-treated epithelia. These results indicate that short-term nasal aeroallergen exposure minimally alters immune cell phenotypes, and instead induces functional changes in OSN physiology that preserve olfactory function.

Toxicogenomics can support regulatory toxicology, but its use is limited by the difficulty of translating molecular responses into mechanistic, decision-relevant interpretations. Adverse Outcome Pathways (AOPs) provide a framework for this translation, yet omics applications require scalable mapping of Key Events (KEs) to molecular features. Here, we present an AI-assisted, multi-step workflow for KE-to-gene mapping that uses embedding-based semantic retrieval to identify candidate ontology/pathway terms, large language model-assisted refinement to filter these candidates, and double-independent expert group curation with rule-based consolidation to finalize mappings and derive confidence scores. Compared with earlier NLP-based approaches, the workflow improves KE-to-ontology/pathway mapping performance and generates candidate annotations that better align with expert judgment while substantially reducing the need for manual augmentation. Explicit gene and protein mentions in KE titles were additionally grounded to improve specificity, and each curated mapping was assigned curator reason codes to support transparent, traceable, and confidence-aware reuse. Applied across AOP-Wiki, the workflow produced a comprehensive KE-to-gene set resource covering 1,254 KEs across 523 AOPs and linking 15,833 human genes. Utility is demonstrated through CTD-based AOP fingerprinting of curated reference chemical groups, highlighting expanded coverage and confidence-informed interpretation of chemical-associated gene signatures in an AOP context. The workflow and resulting resource provide a practical bridge between toxicogenomics and AOP-based mechanistic interpretation and support routine updating and future extension to additional omics layers within OECD Omics2AOP.