Toxins最新文献

Bothrops snakebites pose a significant public health challenge in low- and middle-income regions, often resulting in inflammation, coagulopathy, and renal complications even after antivenom therapy. This study investigated the role of interleukin-33 (IL-33) and endothelial biomarkers in patients with Bothrops envenoming to better understand the mechanisms associated with bleeding and kidney dysfunction. In a prospective cohort of 31 patients from Northeast Brazil, serum levels of IL-33, von Willebrand factor A2 (vWF-A2), angiopoietin-1, angiopoietin-2, syndecan-1, and VCAM-1 were measured at admission and at 10 and 20 h after antivenom administration. Fourteen patients (45%) presented with bleeding at baseline. Traditional clinical and laboratory parameters did not differ between the bleeding and non-bleeding groups on admission; however, IL-33 levels were significantly higher in patients with bleeding. Elevated IL-33 on admission correlated positively with vWF-A2 and estimated glomerular filtration rate, and negatively with angiopoietin-1, suggesting links between inflammation, endothelial dysfunction, and early renal involvement. IL-33 showed a good performance in bleeding patients (AUC = 0.739; IC 95% 0.562-0.917). These findings identified the link between IL-33, early hemorrhage, endothelial dysfunction, and renal involvement in acute Bothrops envenoming. After antivenom therapy, IL-33 levels presented dynamic changes in all patients and require further studies.

Phospholipases A₂ (PLA₂s) are key mediators of the cytotoxic and inflammatory activities of snake venoms. While PLA₂ isoforms from Bothrops diporus venom have been characterized and shown to possess antimetastatic and antiangiogenic properties, their impact on mitochondrial bioenergetics and immune modulation has not yet been investigated. In this study, we examined the bioenergetic and immunomodulatory effects of B. diporus PLA₂s using integrated biochemical, metabolic, and multiplex cytokine analyses. In MDA-MB-231 breast cancer cells, pooled PLA₂s induced a dose-dependent decrease in MTT-reducing activity, increased mitochondrial ROS, caused Δψm hyperpolarization, and decreased NADH autofluorescence, collectively indicating sustained mitochondrial stress. Real-time impedance measurements further revealed a marked inhibition of cell proliferation. In human PBMCs, pooled PLA₂s elicited a dynamic cytokine program, inducing early cytotoxic (Granzyme B) and chemotactic (CCL2, CCL3, CCL4) mediators, followed by late pro-inflammatory and regulatory factors such as IL-6, TNF-β, IL-10 and IL-15. Analysis of a single purified PLA₂ isoform (Fraction 6) confirmed activation of the canonical IL-6/TNF-α/IL-1β axis but uniquely induced IL-10 and CCL20, revealing isoform-specific immunomodulatory properties. Altogether, these findings provide the first integrated characterization of mitochondrial and immune perturbations induced by B. diporus PLA₂s, expanding their recognized biological scope and underscoring their potential as molecular templates for novel pharmacological strategies targeting mitochondrial vulnerabilities or modulating the tumor immune microenvironment.

Facial neuromodulation with botulinum toxin has traditionally been approached from the perspective of wrinkle correction. However, facial expressions primarily arise from coordinated muscular interactions that convey both positive and negative emotional valence. A conceptual framework focused on muscular equilibrium rather than wrinkle severity may therefore offer a more comprehensive, reproducible, and clinically meaningful approach. In this article, we propose the Index of Muscular Equilibrium (IME) Framework, a conceptual model for aesthetic neuromodulation that integrates functional muscle mapping, validated severity scales, and a composite IME score to support personalized treatment planning and outcome assessment. The framework is derived from a narrative review of PubMed-indexed literature on facial muscle activity, emotional expression, and validated clinical assessment tools. It combines a Valence Map to classify positive- and negative-valence muscle groups, a standardized evaluation of static and dynamic hypertonus, a conceptual Plan Score to guide selective neuromodulation, and a feedback-based longitudinal workflow (the IME Loop). Together, these components enable structured assessment of muscular imbalance, integration of established wrinkle severity scales, and translation into individualized, function-oriented treatment strategies, with intended benefits including improved objectivity, reproducibility, and patient communication. By reframing treatment success from the duration of muscle blockade to the duration of expressive harmony, the IME Framework introduces testable constructs for future validation and offers a functional perspective on facial neuromodulation aligned with contemporary affective science.

Background: Vascular calcification (VC) affects up to 90% of patients with end-stage renal disease and increases cardiovascular mortality 3- to 5-fold. Once considered passive mineral deposition, VC is now recognized as an active, toxin-driven process orchestrating vascular smooth muscle cell transdifferentiation, endothelial dysfunction, and matrix remodeling. However, current uremic toxin classifications remain biochemically oriented, providing limited clinical guidance for risk stratification and therapeutic selection.

Methods: This comprehensive review reframes uremic toxin-driven VC through an integrated phenotypic lens, synthesizing molecular mechanisms, clinical biomarkers, and therapeutic targets into a unified translational framework.

Results: We propose five mechanistic-clinical phenotypes representing distinct biological trajectories of vascular injury. These include (1) inflammatory-oxidative (dominated by indoxyl sulfate, p-cresyl sulfate, NLRP3 inflammasome activation), (2) mineral-metabolic (hyperphosphatemia, FGF23 excess, Klotho deficiency), (3) epigenetic-senescent (histone modifications, microRNA dysregulation, cellular senescence), (4) endocrine cross-talk (vitamin D, PTH, gut-derived metabolites), and (5) integrated toxic continuum (convergence of multiple pathways in advanced disease). A comprehensive biomarker panel spanning inflammatory markers, mineral metabolism parameters, epigenetic indicators, and endocrine-gut metabolites enables phenotypic stratification and therapeutic monitoring. Emerging therapies-including tissue-nonspecific alkaline phosphatase inhibition, ectonucleotide pyrophosphatase/phosphodiesterase 1 enzyme replacement, vitamin K₂ activation, senolytic agents, and SNF472 crystal-growth blockade-are mapped to their optimal phenotypic contexts.

Conclusions: This phenotype-oriented paradigm transforms VC from an inevitable complication into a targetable and potentially reversible manifestation of uremic toxicity, establishing a translational foundation for precision-based vascular medicine in chronic kidney disease. The framework enables biomarker-guided patient stratification, rational therapeutic selection, and phenotype-enriched clinical trial design.

This open-label, uncontrolled, single-arm, multicenter, phase 3 study evaluated the efficacy and safety of incobotulinumtoxinA in Japanese patients with blepharospasm. Eligible patients received incobotulinumtoxinA injections at fixed doses (50, 75, or 100 units [U] for those who had previously received botulinum toxin treatment; 50 U for treatment-naïve patients), followed by flexible doses up to 100 U for 48 weeks, with at least 6-week intervals. In total, 29 Japanese patients were enrolled (26 [89.7%] women, mean age 64.6 years, mean baseline Jankovic Rating Scale [JRS] severity score 3.24). The primary endpoint, the least squares mean of change in JRS severity scores from baseline to 6 weeks after the first injection, was -2.08 (95% confidence interval: -2.49, -1.66), meeting the prespecified efficacy criteria. The secondary endpoint results (JRS severity, frequency, and total scores for 48 weeks; Blepharospasm Disability Index; Patient Evaluation of Global Response; and fast blinking test) supported the efficacy of repeated incobotulinumtoxinA injections. Adverse events (AEs) occurred in 19 (65.5%) patients, with eyelid ptosis being the most common treatment-related AE (4 [13.8%] patients). No severe or serious AEs were reported. IncobotulinumtoxinA demonstrated sustained efficacy in Japanese patients with blepharospasm, without new safety concerns. (Japan Registry of Clinical Trials identifier, jRCT2031230711).

Passive transplacental immunity is crucial for neonatal protection from infections. Following Clostridioides difficile (C. difficile) infection, infants do not develop disease, although C. difficile colonization is highly prevalent in infants. This work aimed to characterize humoral immunity specific to C. difficile toxins TcdA and TcdB and to surface proteins FliD and Cwp84, well-known colonizing factors, in pregnant women and their neonates. Anti-C. difficile antibodies were measured in maternal serum, cord blood, and breast milk from 58 healthy pregnant women and their newborns, enrolled in a prospective study, using a quantitative ELISA. Anti-C. difficile antibodies were also measured in pregnant women with C. difficile infection (CDI) in a retrospective peripartum case series. We found a high seroprevalence of IgG specific to the four antigens in healthy pregnant women, regardless of colonization by C. difficile. However, pregnant women exhibited lower concentrations of TcdA-specific IgG antibodies compared to age-matched non-pregnant women. A strong positive correlation between maternal and cord blood IgG specific to TcdA, TcdB, FliD, and Cwp84 was observed, suggesting a transplacental transfer of C. difficile-specific IgG antibodies to neonates. In breast milk, a high seroprevalence of IgA specific to the two toxins was detected, and positive correlations between maternal serum and breast milk antibody levels highlight a preferential transfer of TcdB-specific IgG and Cwp84-specific IgG to breast milk, providing the infant with a protective barrier against C. difficile. Lastly, since pregnant women are at increased risk for C. difficile infection (CDI), we characterized the specific antibody response in a retrospective peripartum case series. Sera from peripartum women with CDI exhibited similar median concentrations of TcdA, TcdB, FliD, and Cwp84 IgM and IgG to those of healthy pregnant women. Moreover, except for one case, antibody concentrations remained stable during the longitudinal evolution of C. difficile response before and after diagnosis of CDI, without any booster effect. Altogether, these data are consistent with antibody-mediated maternal protection of neonates from C. difficile-associated disease. Larger studies exploring immune factors involved in protection from C. difficile-associated disease during pregnancy are needed.

Enniatins (ENNs) are emerging Fusarium mycotoxins detected in food and feed. Despite their widespread occurrence, their toxicity remains poorly understood; thus, advanced in vitro systems that can mimic human physiology are of interest. We evaluated the cytotoxic and genotoxic effects of ENN A1 and ENN B1 exposure on differentiated (DIFF) and undifferentiated (UND) HepaRG liver cells cultured as 2D monolayers and 3D spheroids. Cytotoxicity, assessed by ATP-based luminescence, revealed a time-dependent decrease in inhibitory concentration 50 (IC₅₀) values between 24 h and 48 h across all models. In DIFF HepaRG cells, ENN A1 IC₅₀ values in 3D spheroids decreased from 14.4-18.2 µM at 24 h to 2.2-3.0 µM at 48 h, reaching values comparable to those measured in 2D DIFF cells at 48 h (2.2-2.6 µM), while no IC₅₀ could be determined in 2D at 24 h. For ENN B1, a pronounced time-dependent toxicity was observed, with IC₅₀ values in 3D DIFF spheroids decreasing from 4.1-6.6 µM at 24 h to 1.3-1.6 µM at 48 h, remaining lower than those measured in 2D DIFF cells at 48 h (2.4-3.0 µM). ENN A1 primarily induced apoptotic responses, whereas both ENN A1 and B1 were associated with necrotic responses, and ENN B1 induced a transient and limited autophagic signal, suggesting a minor role for autophagy. To further characterize cellular responses to ENN exposure, spheroids cultured in microfluidic chips were sectioned, and proliferation (Ki67), DNA damage (γH2AX), and apoptosis (cleaved caspase-3) was assessed. Immunostaining revealed no proliferative response, whereas significant DNA damage was detected, particularly in DIFF spheroids. At low, sub-cytotoxic concentrations (~5 µM, 24 h), ENN A1 induced significant DNA damage, as shown by increased γH2AX levels, while cytotoxic effects were only observed at higher concentrations (IC₅₀ ~ 18 µM, 24 h), supporting a potential genotoxic effect independent of cytotoxicity. Despite the structural similarities between ENN A1 and ENN B1, our results highlighted distinct cell death pathways between the two analogues. Both ENNs were detected throughout spheroids without evidence of peripheral restriction, although a homogeneous functional test could not be conclusively demonstrated. Overall, the 3D HepaRG spheroid model proved to be a more physiologically relevant system, offering differential sensitivity, as well as enhanced mechanistic insight, compared to 2D cultures.

The endo-lysosomal channel TRPML2 regulates key processes like membrane trafficking and autophagy, which are hijacked by many RNA viruses during endocytic entry. However, the development of TRPML2-targeted therapeutics has been hindered by a notable lack of high-affinity and selective peptide-based activators. Scorpion venom peptides, honed by evolution for exceptional specificity toward diverse membrane ion channels, represent a promising, underexplored natural library for discovering novel pharmacological probes and drug leads. Here, we screened and identified seven candidate peptides interacting with TRPML2 using co-immunoprecipitation combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of the Mesobuthus martensii venom. Based on molecular docking analysis, the top four candidates-MMTX, BmP05, BmTX1, and BmKK12-were selected for chemical synthesis, oxidatively cyclized to form their native disulfide-bridged conformations, and subsequently purified and characterized by analytical HPLC and MS. Calcium imaging confirmed that two of the four oxidized peptides, BmP05 and BmKK12, exhibited superior potency in inducing a sharp increase in Ca²⁺ influx. Crucially, BmP05 and BmKK12 demonstrated potent, concentration-dependent inhibition of Zika virus (ZIKV) replication at the RNA level at non-cytotoxic concentrations, whereas the weaker activators MMTX and BmTX1 did not. The current study first reports animal venom-derived peptides that function as specific TRPML2 agonists with concomitant antiviral activity. Together, our findings provide not only new molecular probes for dissecting TRPML2 biology but also a pioneering strategy for developing host-directed, broad-spectrum therapeutics against viruses dependent on endo-lysosomal entry.

Our current understanding of snake venom is highly biased towards species known to be medically significant in human envenomations. This vastly under-represents the true evolutionary and ecological breadth of snake venom, with gaps spanning entire clades and unique lifestyles. As a result, many genera of rear-fanged snakes lack well-understood venom profiles despite these taxa composing around 65% of known extant snake species. Methodological challenges associated with venom extraction have long been a key reason responsible for the lack of venom research on this group. Modern advancements in venomics technologies have allowed researchers to overcome many of these challenges and investigate the venom components of understudied genera. The genus Coniophanes (black-striped snakes) presents an ideal system for investigating venom and the venom delivery system in a rear-fanged venomous species with well-documented accounts of human envenomations. We sequenced and annotated de novo transcriptomes of the Duvernoy's gland (DVG) for seven individuals across four species of Coniophanes (Dipsadidae) and confirmed toxin expression in representative venom proteomes. We assessed interspecific venom variation within this genus and further examined intraspecific venom variation within C. imperialis. We found that toxins account for 38.8% to 66% of the total DVG transcriptomes and that 18 toxin families are represented in this genus, with prominent expression of cystine-rich secretory proteins (CRiSPs) in three species and snake venom metalloproteinases (SVMPs) in all four species. In addition, we used diffusible iodine-based contrast-enhanced computed tomography (diceCT) to better understand the venom delivery system for C. fissidens, a widespread species within this genus, showcasing enlarged, grooved, rear fangs in close proximity to a prominent DVG. We provide the first ever characterization of the venom profiles of Coniophanes, highlight venom variation between and within species, and outline the venom delivery system of this understudied genus.

Advanced chronic kidney disease (CKD) is associated with impaired humoral immunity, contributing to increased infection-related mortality and suboptimal vaccine responses, as notably observed during the COVID-19 pandemic. CKD is also marked by the accumulation of uremic toxins, but whether they directly influence T and B cell functionality remains unclear. In this translational study, we integrated clinical and biological data from 106 CKD patients with mechanistic insights from in vitro and in vivo murine models to identify the mechanisms underlying CKD-associated defects in humoral responses against T cell-dependent antigens. Contrary to our initial hypothesis, indoxyl sulfate-despite its known ability to activate Aryl hydrocarbon Receptor signaling in monocytes-did not directly impair T-B cell cooperation in coculture assays. Similarly, plasma levels of ten major uremic toxins showed no correlations with vaccine-induced antibody titers in patients. Instead, systemic inflammation emerged as the primary driver of defective humoral immunity. Murine models further confirmed that inflammation, rather than uremia alone, induces lymphopenia, disrupts lymphoid architecture, and ultimately impairs antibody production. These findings indicate that CKD-associated inflammation, rather than a direct effect of uremic toxins on adaptive immune effectors, underlies humoral immune dysfunction in CKD. Targeting inflammation may, therefore, offer a promising strategy to improve vaccine efficacy and reduce infection-related complications in this vulnerable population.