Search Results (427)

Benzo[a]pyrene (B[a]P), a ubiquitous environmental pollutant, poses a significant threat to male reproductive health, but the underlying latent molecular mechanisms remain virtually unknown. This study investigated the effects of embryonic B[a]P exposure on testicular function and spermatogenesis in F0 and F1 adult male medaka (Oryzias latipes). Embryos were exposed to sublethal concentrations (2.5, 20, and 80 μg/L) for 8 days and then raised in clean water until they reached adulthood. Transcriptomic analysis of F0 testicular tissues revealed widespread dysregulation of critical pathways. Exposure impaired the brain–pituitary–gonadal axis by disrupting GnRH signaling and downregulating genes encoding key steroidogenic enzymes (CYP17A1, HSD3B2), indicating suppressed testosterone biosynthesis. Concurrently, pathways essential for cellular energy metabolism (AMPK signaling, insulin signaling), amino acid biosynthesis, and cytoskeletal organization (actin cytoskeleton, focal adhesion) were profoundly altered. Furthermore, B[a]P activated apoptotic pathways and disrupted the balance between cell survival (PI3K-Akt signaling) and death, compromising spermatogenic cell fate. These molecular disruptions manifested in drastic physiological impairments, including a reduced gonadosomatic index, decreased sperm motility, and compromised fertilization success in F0 males, although these effects were recovered in the F1 generation. This study provides a comprehensive molecular basis for the long-term reproductive toxicity of early-life B[a]P exposure. Full article

Hexaflumuron, a benzoylurea insecticide, exhibits high toxicity against various insect pests. Sublethal doses of hexaflumuron significantly impair nymphal development and subsequent fecundity in the resulting Apolygus lucorum (Meyer-Dür) adults. However, the effects on adults of A. lucorum that are exposed to sublethal concentrations of hexaflumuron are not known. In this study, we evaluated the toxicity of hexaflumuron to 1st- and 3rd-instar nymphs, as well as one-day-old adults, of A. lucorum using an artificial diet with hexaflumuron incorporated. Acute toxicity bioassays determined the median lethal concentration (LC₅₀) for 1st- and 3rd-instar nymphs of A. lucorum to be 0.311 and 0.337 mg/L. In contrast, the LC₅₀ level for one-day-old adults of A. lucorum was 13.193 mg/L. To evaluate the sublethal effects of hexaflumuron on 3rd-instar nymphs, we used LC₁₀, LC₂₀, and LC₅₀ concentrations (0.018, 0.127, and 0.337 mg/L), fed for 48 h. The exposure of 3rd-instar nymphs to the LC₅₀ concentration significantly reduced the fecundity of adults. We also exposed one-day-old adults to LC₁₀, LC₂₀, and LC₅₀ dietary concentrations (0.089, 4.587, and 13.193 mg/L) for 48 h. Exposure to the LC₁₀ and LC₂₀ concentrations caused significant reductions in longevity and fecundity in adult females. The LC₅₀ concentration also caused a significant reduction in the longevity of adult males and the egg hatching rate. An understanding of these sublethal impacts can facilitate the development of effective control strategies targeting A. lucorum. Full article

Electric fields (EFs) have emerged as effective, non-chemical tools for modulating microbial populations in complex matrices such as wastewater. This review consolidates current advances on EF-induced alterations in microbial structures and functions, focusing on both vegetative cells and spores. Key parameters affected include membrane thickness, transmembrane potential, electrical conductivity, and dielectric permittivity, with downstream impacts on ion homeostasis, metabolic activity, and viability. Such bioelectrical modifications underpin EF-based detection methods—particularly impedance spectroscopy and dielectrophoresis—which enable rapid, label-free, in situ microbial monitoring. Beyond detection, EFs can induce sublethal or lethal effects, enabling selective inactivation without chemical input. This review addresses the influence of field type (DC, AC, pulsed), intensity, and exposure duration, alongside limitations such as species-specific variability, heterogeneous environmental conditions, and challenges in achieving uniform field distribution. Emerging research highlights the integration of EF-based platforms with biosensors, machine learning, and real-time analytics for enhanced environmental surveillance. By linking microbiological mechanisms with engineering solutions, EF technologies present significant potential for sustainable water quality management. Their multidisciplinary applicability positions them as promising components of next-generation wastewater monitoring and treatment systems, supporting global efforts toward efficient, adaptive, and environmentally benign microbial control strategies. Full article

Hydroxychloroquine (HCQ), an antimalarial commonly used in autoimmune and dermatological conditions, may exert photoprotective effects, though its role against high-energy visible light (HEVL) remains underexplored. This study evaluated HCQ’s impact on cell viability and oxidative stress in human keratinocytes (HaCat cells) exposed to HEVL blue light. Cells were treated with HCQ (1, 2.5, or 5 µM) and irradiated with blue light doses (4.5–72 J/cm²). Assays assessed cell viability (XTT), reactive oxygen species (ROS) production, and the expression of oxidative stress-related enzymes: superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT). Results showed that low blue light doses triggered endogenous protective responses, which HCQ enhanced, potentially via SOD activation. However, higher irradiation levels caused extensive cellular damage that overwhelmed HCQ’s protective capacity. These findings suggest HCQ may confer in vitro photoprotection against sublethal HEVL exposure by modulating oxidative stress responses, although this effect diminishes beyond a certain damage threshold. Full article

Klebsiella pneumoniae strains that are resistant to carbapenems are of great concern. Exposure to low concentrations of antibiotics may influence tolerance to antibiotics. Novel antibiotics and treatment options are thus needed, and this need is exacerbated by the rapid and global spread of antibiotic resistance. In this study, we determined the global proteome changes in a K. pneumoniae strain (CCUG 70747) carrying carbapenem resistance genes when exposed to low concentrations of ertapenem. Quantitative proteomics was achieved by the tandem mass tag labeling of peptides generated by trypsin proteolysis and mass spectrometry analysis. Bioinformatics analyses were used to observe changes in protein abundance, as well as the gene ontology (GO) terms and pathways associated with the differentially expressed proteins. The number of proteins detected with significant differential abundance were 87 at the highest concentration applied and 61 in the lowest concentration, all compared with the strain cultured without any antibiotics present. Several of these proteins, as well as the GO terms and pathways associated with the proteins, were linked to mechanisms of antibiotic resistance. However, this strain encodes a carbapenemase and other beta-lactamases, and thus, as expected, presented a reasonably modest adaptation in the global proteome upon exposure to the low concentrations of ertapenem applied. Nevertheless, our study identifies pathways that may lead to adaptation under sublethal concentrations of antibiotics leading to strains with higher tolerance. Full article

Beta-cypermethrin is widely applied in Korean pine (Pinus koraiensis Siebold & Zucc.) seed orchards to control cone- and seed-infesting moths (e.g., Dioryctria spp.), yet its Wsublethal risks to non-target beneficial arthropods remain insufficiently characterized. Here, we systematically evaluated the ecological and physiological consequences of beta-cypermethrin exposure on the key parasitoid wasp Baryscapus dioryctriae Yang & Song, an important biological control agent in P. koraiensis forests. Adult wasps were exposed to LC₃₀ and LC₅₀ residue concentrations, and sublethal effects were quantified across reproductive, developmental, and biochemical endpoints over two generations. Sublethal exposure resulted in significant reductions in parasitism rates and offspring emergence, as well as altered developmental durations and adult longevity in both F₀ and F₁ generations. Enzymatic assays revealed time-dependent activation of detoxification enzymes (GST, CarE, AChE) alongside suppression of antioxidant defenses (CAT strongly; SOD early with partial recovery; POD biphasic), consistent with a sustained oxidative-stress burden. LC-MS/MS residue analysis further confirmed the accumulation and slow clearance of both beta-cypermethrin and its metabolite 3-phenoxybenzoic acid (PBA) within parasitoid tissues. These findings collectively demonstrate that even non-lethal concentrations of beta-cypermethrin can undermine the ecological fitness and persistence of B. dioryctriae, posing a tangible threat to the sustainability of biological control services. To safeguard beneficial parasitoids, integrated pest management strategies must incorporate selective insecticide use and exposure mitigation, especially in forest habitats where biological control is indispensable. Full article

Levonorgestrel (LNG), a synthetic progestin widely used in pharmaceuticals, is increasingly recognized as an emerging aquatic contaminant capable of exerting adverse biological effects beyond endocrine disruption. Acting in a xenobiotic-like manner, LNG may perturb redox homeostasis and induce oxidative stress in non-target species. To elucidate these mechanisms, this study integrates experimental toxicology with supervised machine learning to characterize tissue-specific and dose–time related oxidative responses in adult Zebrafish (Danio rerio). Fish were exposed to two environmentally relevant concentrations of LNG (0.312 µg/L; LNG-L and 6.24 µg/L; LNG-H) and a solvent control (LNG-C) for 24, 48, and 96 h in triplicate static bioassays. Redox biomarkers—superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and malondialdehyde (MDA)—were quantified in liver and muscle tissues. LNG-H exposure elicited a time-dependent increase in SOD activity, variable CAT responses, and a marked elevation in hepatic GPx, with sustained MDA levels indicating persistent lipid peroxidation. Five classification algorithms (Logistic Regression, Multilayer Perceptron, Gradient-Boosted Trees, Decision Tree and Random Forest) were trained to discriminate exposure outcomes based on biomarker profiles; GBT yielded the highest performance (96.17% accuracy), identifying hepatic GPx as the most informative feature (AUC = 0.922). Regression modeling via Extreme Gradient Boosting (XGBoost) further corroborated the dose- and time-dependent predictability of GPx responses (R² = 0.922, MAE = 0.019). These findings underscore hepatic GPx as a sentinel biomarker of LNG-induced oxidative stress and demonstrate the predictive utility of machinelearning-enhanced toxicological frameworks in detecting and modeling sublethal contaminant effects with high temporal resolution in aquatic systems. Full article

Listeria monocytogenes is a foodborne pathogen capable of contaminating ready-to-eat meat products, e.g., frankfurters. Post-packaging mild heat treatment via water immersion is commonly employed; however, this may be sublethal to cells located in protected niches or beneath the product surface. The objectives of this study were to evaluate thermal injury of L. monocytogenes on frankfurters at single-cell versus population level and to comparatively estimate pathogens’ physiological status. Pork frankfurter-type sausages were inoculated (ca. 7.0–7.5 log CFU/cm²) with L. monocytogenes strain EGDE-e. Heat treatment was performed at 61 °C (max. 60 min) and 64 °C (max. 12 min). To determine the injured subpopulation from the total, tryptic soy agar with 0.6% yeast extract (TSAYE), supplemented or not with 5% NaCl, was used. Plating-based quantification of injured cells was compared to CFDA/PIstained cells analysed by fluorescence microscopy and quantified with Fiji software. Injury was recorded mainly after 2 and 4 min at 64 °C, whereas no injury was detected at 61 °C, at population level. Following exposure to 61 °C for 60 min, culturable cells dropped below the enumeration limit (0.3 log CFU/cm²), while a considerable number of CFDA⁺/PI⁻ and CFDA⁺/PI⁺ cells indicated viable-but-non-culturable induction and sublethal injury, respectively. These findings suggest that non-culturability may limit the accuracy of solely culture-based enumeration methods. Full article

Honeybees (Apis mellifera ligustica Spin.) are the most significant pollinating insects, playing a vital role in maintaining biodiversity. In healthy colonies, the reproductive success of the queen and the genetic contribution of drones are essential for long-term survival, directly affecting brood production, genetic diversity, and environmental adaptability. While the physiological and behavioral impacts of chemical pesticides on worker bees are relatively well documented, the risks to reproductive bees (queens and drones) remain poorly understood. In this study, we comprehensively assessed the effects of the widely used neonicotinoid thiamethoxam on the key developmental and physiological parameters in reproductive bees, including survival, pupation rate, eclosion rate, hormone titers, and detoxification enzyme activities. Our finding reveals that thiamethoxam exerts sublethal effects on larvae, significantly impairing the fitness of reproductive bees. Specifically, exposure altered juvenile hormone III, ecdysone titer, and acetylcholinesterase activity in reproductive larvae, with these effects showing a negative correlation with pesticide concentration. Notably, CYP450 activity exhibits a biphasic dose–response, with an initial elevation followed by a decline after reaching peak levels. These results demonstrate that thiamethoxam adversely affects the growth and development of reproductive bees, potentially compromising colony stability. By elucidating these sublethal effects, our study provides critical insights for mitigating pesticide-related threats to honeybee health. Our findings may help to scientifically and rationally avoid the potential risks of chemical pesticides to honeybees. Full article

The increasing use of water-based drilling muds in offshore oil and gas operations has raised concerns about potential ecological risks of their primary components, such as bentonite, on marine organisms. To date, the biological effects of bentonite on benthic species remain poorly understood. This study aimed to evaluate the physiological and oxidative stress responses of Pacific abalone (Haliotis discus hannai) exposed to varying concentrations (20–3000 mg/L) of bentonite over a 10-day period. Short-term exposure (up to 7 days) to bentonite did not result in significant mortality across treatment groups; however, partial mortality was observed in the highest concentration group (3000 mg/L) on day 8. Biochemical analyses revealed elevated levels of hydrogen peroxide and malondialdehyde, particularly in higher concentration groups, indicating oxidative stress. Antioxidant enzyme activities showed concentration- and time-dependent changes, with early activation followed by suppression under prolonged exposure. Total antioxidant capacity also declined over time in high-concentration groups. These findings indicate that while bentonite may not be acutely lethal to abalone, it can trigger sublethal oxidative stress responses, particularly under chronic exposure conditions, underscoring the importance of evaluating long-term physiological impacts of suspended drilling particulates and the need for research on a wider range of marine species. Full article

Doxorubicin (Dox) is not a first-line treatment for melanoma due to limited antitumor efficacy and dose-dependent cardiotoxicity. However, sublethal doses may trigger adaptive cellular responses that influence tumor progression and systemic toxicity. Small extracellular vesicles (EVs) are key mediators of intercellular communication and can carry bioactive molecules that modulate both the tumor microenvironment and distant tissues. This study investigates how sublethal Dox exposure alters EV biogenesis and cargo in A375 melanoma cells and explores the potential implications for cardiovascular function. We treated human A375 melanoma cells with 10 nM dox for 96 h. EVs were isolated using differential ultracentrifugation and size exclusion chromatography. Vesicle characterization included Immunocytochemistry for CD63, CD81, CD9, Rab7 and TSG101, scanning electron microscopy (SEM) Nanoparticle Tracking Analysis (NTA), and Western blotting for CD81 and CytC. We analyzed cytokine content using cytokine membrane arrays. Guinea pig cardiomyocytes were exposed to the isolated vesicles, and mitochondrial activity was evaluated using the MTT assay. Statistical analysis included t-tests, ANOVA, Cohen’s d, and R² and η². Dox exposure significantly increased EV production (13.6-fold; p = 0.000014) and shifted vesicle size distribution. CD81 expression was significantly upregulated (p = 0.0083), and SEM (microscopy) confirmed enhanced vesiculation. EVs from treated cells were enriched in TGF-β (p = 0.0134), VEGF, CXCL1, CXCL12, CCL5, IL-3, IL-4, IL-10, Galectin-3, and KITLG. Cardiomyocytes exposed to these vesicles showed a 2.3-fold reduction in mitochondrial activity (p = 0.0021), an effect absent when vesicles were removed. Bioinformatic analysis linked EV cargo to pathways involved in cardiac hypertrophy, inflammation, and fibrosis. As conclusion, sublethal Doxorubicin reprograms melanoma-derived EVs by enhancing their production and enriching their cargo with profibrotic and immunomodulatory mediators. These vesicles may contribute to tumor progression and cardiovascular physiopathology, suggesting that targeting EVs could improve therapeutic outcomes in cancer and cardiovascular disease. Full article

Cyclaniliprole is a novel third-generation anthranilic diamide insecticide which has broad-spectrum efficacy against various pests, including aphids. Rhopalosiphum padi and Schizaphis graminum are the two primary aphid species that infest wheat crops. This investigation evaluates cyclaniliprole’s acute toxicity and sublethal and transgenerational effects on both aphid species. The acute toxicity assessment revealed obvious insecticidal activity, with 24 h LC₅₀ values of 38.56 mg/L for R. padi and 33.71 mg/L for S. graminum. Sublethal exposure (LC₁₅ and LC₃₅ in R. padi; LC₃₅ in S. graminum) significantly reduced adult longevity and fecundity in the F₀ generation. In the F₁ generation, cyclaniliprole at LC₃₅ significantly reduced the fourth nymph stage in R. padi, whereas at LC₁₅, it shortened the third nymph stage duration in S. graminum compared to the control. Sublethal concentrations (LC₁₅ and LC₃₅) of cyclaniliprole significantly reduced age-stage-specific survival rate (s_xj), age-specific survival rate (l_x), age-specific maternity (l_xm_x), and age-stage life expectancy (e_xj) in the F₁ generation of R. padi, while only LC₃₅ decreased l_x, l_xm_x, and e_xj in S. graminum. Additionally, LC₃₅ significantly reduced the net reproductive rate (R₀) in the F₁ generation of R. padi compared to the control. These findings suggest that cyclaniliprole exhibit notable acute toxicity against both aphid species and that sublethal concentrations adversely affected the F₀ generation, with no observed hormetic effects in the F₁ generations of R. padi and S. graminum. The findings offer valuable insights for assessing the comprehensive insecticidal potential of cyclaniliprole. Full article

Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) is one of the most destructive pests of stored grains worldwide. Sublethal concentrations of insecticides are known to influence insect behavior, potentially disrupting critical processes such as mating. This study investigated the effects of λ-cyhalothrin at the lethal concentration (LC) values LC₁₀ and LC₃₀ and lateralization on the mating behavior patterns of S. zeamais males. Results showed that the exposure to sublethal concentrations of λ-cyhalothrin significantly altered the copulation success rate and key time-related parameters, including mate recognition and copulation duration, while the lateralization caused significant differences in mating time-related parameters within each tested group (control, LC_10, and LC₃₀). Additionally, the λ-cyhalothrin-treated groups showed prolonged mate recognition times and required more mounting attempts to achieve mating. These findings highlight the potential of sublethal insecticide applications to control S. zeamais populations by impairing reproduction. Full article

Honeybees (Apis mellifera) are indispensable pollinators vital to global biodiversity, ecosystem stability, and agricultural productivity, and they promote over 35% of food crops and 75% of flowering plants. Yet, they are in unprecedented decline, partly as a result of neonicotinoid pesticide use elsewhere. These effects on honey bee health are synthesized in this paper through molecular, physiological, and behavioral data showing that sublethal effects of neonicotinoids impair honey bee health. As neurotoxic insecticides that target nicotinic acetylcholine receptors (nAChRs), these insecticides interfere with neurotransmission and underlie cognitive impairment, immune suppression, and oxidative stress. Developmental toxicity is manifested in larvae as retarded growth, reduced feeding, and increased death; queen and drone reproduction are impaired, lowering colony viability. As a result, adult bees have shortened lives and erratic foraging, are further disoriented, and experience impaired navigation, communication, and resource collection. Together, these effects cascade to reduced brood care, thermoregulatory failure, and heretofore unrecognized increased susceptibility to pathogens, increasing the probability of colony collapse at the colony level. Contaminants such as pesticides may cause pollinator exposure and, in turn, may cause their population to be undermined if they are not mitigated; therefore, urgent mitigation strategies, including integrated pest management (IPM), regulatory reforms, and adoption of biopesticides, are needed to mitigate pollinator exposure. The focus of this review lies in the ecological necessity of restructuring how agriculture is managed to simultaneously meet food security and the conservation of honeybee health, the linchpin of global ecosystems. Full article

Lambda-cyhalothrin (LCY), a widely used pyrethroid insecticide, is toxic to bees—vital pollinators experiencing global declines; however, its molecular effects during early development remain poorly understood. We investigated the molecular mechanisms underlying chronic sublethal exposure to LCY in the larval and adult stages. Larvae were exposed to LCY (0.004 µg active ingredient/larva), with four groups examined: solvent-treated larvae group (SLG), solvent-treated adult group (SAG), LCY-treated larvae group (LLG), and LCY-treated adult group (LAG). We identified 1128 and 168 significantly altered genes in LLG vs. SLG and LAG vs. SAG, respectively, with 125 larval- and 25 adult-specific DEGs, indicating stage-dependent toxicity. LCY dysregulated processes such as cuticle formation, sulfur metabolism, oxidoreductase activity, and neuropeptide signaling in larvae, while adults exhibited altered redox balance, peptide receptor signaling, and monoamine transport. Neuroactive signaling disruptions were observed in both stages, with additional effects on motor function, amino acid metabolism, and glycolysis in larvae; whereas adults exhibited altered lipid biosynthesis and energy metabolism. Downregulated genes involved in chitin metabolism and antioxidant defenses in larvae suggested compromised exoskeletal integrity and increased vulnerability. Overall, our findings highlight the long-term molecular consequences of early-life exposure and emphasize the need for safer pesticide practices to protect pollinator health. Full article