Search Results (197)

Neonicotinoids are widely used pesticides that have caused a catastrophic decrease in bee and bumblebee populations worldwide. In addition to insects, neonicotinoids induce toxic effects in other species, including lizards, birds, and mammals. Previous studies have shown that gestational exposure to thiacloprid promotes transgenerational effects in the testes and thyroid. In this project, we described the epigenetic effects of thiacloprid on prostate tissue in directly exposed F1 and non-directly exposed F3 outbred Swiss male mice. We used paraffin sections for morphological analysis and frozen tissue for immunofluorescence analysis, RT–qPCR, and protein analysis. We purified histones and analyzed them through Western blot. We used ChIP–qPCR for histone H3K4me3 occupancy analysis. A tendency to increase in epithelial hyperplasia in F1 but not in F3 prostate was detected. Elevated levels of phosphorylated histone H3 at serine 10, a marker of mitosis, in both the F1 and F3 prostates were noted. A significant increase in the level of the Ki-67 marker of proliferation was detected in the F1 but not in the F3 anterior prostate. Hox gene expression was upregulated in the F1 and downregulated in the F3 prostate. The changes in gene expression were positively associated with histone H3K4me3 alterations at the promoters of the Hoxa and Hoxb13 genes. We determined that regions of Hox genes that play important roles in prostate development had altered DNA methylation in the sperm of F1 and F3. These alterations in DNA methylation were negatively related to gene expression. This is an observational study, as it was part of our previous research on the effects of thiacloprid on the testis and thyroid. Our analysis revealed that gestational exposure to thiacloprid induced an increase in cell proliferation in the prostates of directly exposed F1. Some persistent epigenetic alterations in the prostate of F3 males were not associated with phenotypic changes. Full article

The extensive utilization of TMX, a substance characterized by its high toxicity towards honeybees, has exerted a deleterious influence on the employment of neonicotinoid insecticides and the proliferation of bee colonies. However, there is a lack of effective solutions to mitigate the toxicological impact of neonicotinoid insecticides on bees. The present study proposes a method of using MB to alleviate TMX poisoning in honeybee (Apis mellifera ligustica) larvae. The results demonstrated that when bee larvae ingested MB at a concentration of 0.32 mg·L⁻¹, the mortality rate of larvae could be reduced from 47.2% to 25.0%. Transcriptome analysis identified the honeybee dihydrolipoyl dehydrogenase (AmDld) gene as one of the main genes involved in the function of MB. AmDld was highly expressed in larval hemolymph. Its expression levels and enzymatic content were suppressed by either TMX or MB alone but restored by the TMX+MB combination. RNAi-mediated knockdown of AmDld decreased AmDld content and increased larval mortality under the TMX+MB co-treatment from 25.0% to 40.6%. This indicated that the TMX+MB combination rescued AmDld levels, thereby alleviating TMX toxicity to bee larvae. The present study has demonstrated that the ingestion of MB by honeybee larvae has the capacity to reduce the toxicity of TMX, a toxic substance, through the action of the AmDld gene. This provides a novel approach to mitigating pesticide poisoning in bees. Full article

Background/Objectives: Propolis is a complex bee product with a composition that varies according to local vegetation, environmental conditions, and bee foraging behaviours. Recently, gas chromatography–mass spectrometry (GC–MS) has been employed in Uganda to analyse its volatile components. This study examined Ugandan propolis non-volatile metabolites to determine chemotypes and identify antibacterial compounds. Methods: Ethanolic extracts were analysed using liquid chromatography–high-resolution quadrupole time-of-flight mass spectrometry (LC-HR-QTOF-MS) in an untargeted MS/MS mode. Data processing was carried out using MZmine, then annotated with Global Natural Products Social Molecular Networking (GNPS) and SIRIUS. Chemometric methods assisted in identifying regional chemical signatures. Metabolites highlighted by the heatmap were evaluated for antibacterial activity using molecular docking against bacterial targets, followed by ADMET (absorption, distribution, metabolism, excretion, and toxicity) assessments. Results: Out of 3252 features, 234 and 52 putative compounds were annotated in GNPS and SIRIUS, respectively, as indicated by molecular networking, suggesting high chemical complexity. The chemical space mainly comprises flavonoids (including glycosides, aglycones, methylated, and prenylated derivatives), phenolic acids, amides, hydroxycinnamate derivatives, lignans, megastigmanes, and various diterpenoid skeletons. Multivariate analyses clearly distinguish geographical chemotypes, separating flavonoid-rich regions from diterpenoid-rich regions. Docking studies revealed flavonoids, diterpenoids, and lignans with strong predicted antibacterial activities and favourable ADMET profiles. Conclusions: This study provides the first LC–MS characterisation of the non-volatile metabolome of Ugandan propolis, thereby expanding its chemical diversity. Metabolomics and computational approaches lay a foundation for future ecological, chemotaxonomic, and pharmacological research. Full article

Apis mellifera L. is an important pollinator of both wild and domesticated crop plants, thus greatly contributing to plant biodiversity and commercial agriculture. However, in field conditions, honey bees remain exposed to different pesticides which ultimately affect colony health parameters and their associated ecological services. In the current study, the individual toxicities of sub-lethal doses of two distinct insecticides (bifenthrin and acetamiprid) belonging to different groups (pyrethroid and neonicotinoid) were assessed against the foraging activity, social interactions, and longevity of A. mellifera. The bees were exposed to individual doses of both insecticides via the dietary trophic route through contaminated pollen and nectar under natural field conditions. Sunflower crop (Hysun-33) was sown at nine different sites with an isolation distance of 3 km, and was treated with different doses (1/2, 1/4, 1/10, and 1/20 of the recommended field doses) of both insecticides. However, the untreated control crop plots were not subjected to any chemical treatments (bee colonies received no insecticide, and served as the baseline for making comparison). Twenty-seven bee colonies were introduced in these sites after seven days of treatment applications. Significant differences were observed in the foraging activity of A. mellifera (including bees going out from the hive, returning foragers, and those carrying pollens). The fecundity, adult longevity, and social behaviors like trophallaxis and antennation were significantly lower in bees exposed to higher individual insecticidal concentrations. However, the hatching duration, larval duration, and pupal duration were not affected by the tested insecticidal treatments. Overall, these findings demonstrate that the dietary trophic exposure of sub-lethal doses of insecticides compromised colony activities, which is indeed a matter of concern regarding the existing pesticide application methods in different agro-ecosystems. Such impacts may ultimately impair the survival of colonies, particularly when bees remain exposed to these chemicals over an extended period of time. Therefore, future studies must consider the pesticide application techniques and their application timing to mitigate the direct and indirect negative impacts of pesticides on pollinators. Full article

Background: The incidence of dementia, especially Alzheimer’s disease (AD), is rising, with over 55 million affected globally. Therefore, this disease, for which there is no adequate treatment, is more frequent and prevalent in women. Royal jelly, a bee secretion, is known for its health benefits and contains proteins, carbohydrates, lipids, minerals, polyphenols, enzymes, and B vitamins, as well as anti-inflammatory and antioxidant properties relevant to AD. Thus, we aimed to investigate the chemical compounds in royal jelly extract and their effect on neurobehavioral changes in an AD female model. Methods: In vitro studies were used to investigate the chemical and physicochemical properties of the royal jelly extract. In vivo studies, we divided female mice into five groups (n = 25): Control (C), Alzheimer (ALZ), ALZ standard (ALZ-STD, rivastigmine 1 mg/Kg), ALZ-D1 (royal jelly 150 mg/kg), and ALZ-D2 (royal jelly 300 mg/kg). The mice received the treatments orally at 45 days. We induced the AD model by orally administering aluminum chloride at 100 mg/kg and intraperitoneally injecting D-galactose at 120 mg/kg for 45 consecutive days, after which we subjected the animals to the radial arm maze, Morris water maze, elevated plus maze, and forced swim tests. Results: Analyses showed moderate acidity and a rich bioactive profile, with flavonoids being more prevalent. Antioxidant activity tests indicated moderate efficacy, while FTIR-ATR analysis revealed the chemical complexity of royal jelly. The royal jelly extract used in the study did not induce toxicity in vivo. Notably, royal jelly improved cognitive deficits, neurodegeneration, and reduced anxiety in AD. Conclusions: The study suggests that royal jelly extract has promising neuroprotective properties and could be a viable natural therapeutic option for AD. Full article

Background: Pesticide toxicity to insects is an important adverse effect with a potentially large ecological impact when considering the effect on beneficial insects, as pollinators. The assessment of this endpoint is necessary to avoid applying ecologically dangerous pesticides. Aim of the study: Assessment of the availability of the Monte Carlo method for the development of a model for toxicity (pLD50) towards bees and other pollinators. In addition, the index of ideality of correlation is examined as a possibility to increase the statistical quality of quantitative structure–activity relationships (QSARs) for the toxicity of pesticides to pollinators. Main results and novelty: models with good performance on the toxic effect of pesticides towards different pollinators, wrapping acute and chronic effects, using the Monte Carlo method for QSAR analysis. Full article

This study investigates the synthesis and potential applications of the coordination compound cobalt(III) complex tris[N-(prop-2-en-1-yl)hydrazinecarbothioamide]-cobalt(III) chloride ([Co(Tsc)₃]Cl₃). The complex has been synthesized via the reaction of cobalt(II) chloride hexahydrate with N-(prop-2-en-1-yl)hydrazinecarbothioamide in ethanol. Its antioxidant activity has been evaluated using 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay, demonstrating a significant effect with an IC₅₀ of 7.3 µmol/L. Toxicity evaluations using Daphnia magna showed a low half maximal inhibitory concentration (LC₅₀) of 56.3 µmol/L. Experimental results have showed that [Co(Tsc)₃]Cl₃ significantly elevated the total antioxidant status (TAS) of the hemolymph of honeybees and larvae, increasing it by 5 and 8 times, respectively. The IC₅₀ values for antioxidant activity were 2.5 mg/mL in bee hemolymph and 1.3 mg/mL in larval hemolymph, notably lower than control values of 13.6 mg/mL and 10.0 mg/mL. The stimulatory effect of the coordination compound [Co(Tsc)₃]Cl₃ on TAS was five times higher than that of vitamin C. Additionally, [Co(Tsc)₃]Cl₃ exhibited acaricidal properties, effectively inhibiting Varroa destructor with an lethal concentration (LC₅₀) of 0.2 µmol/L. These findings indicate that this cobalt complex could serve both a natural antioxidant and an effective acaricide, offering a promising approach to improv bee health and sustainability in apiculture. Full article

This study investigates the phenomenon of ethanol hormesis in honeybees (Apis mellifera) infected with Vairimorpha (Nosema) spp., a widespread parasite that significantly impacts bee health and colony survival. Hormesis refers to a biphasic response where low doses of potentially harmful substances may elicit beneficial effects, contrasting with the detrimental impacts observed at higher concentrations. We hypothesized that low ethanol concentrations could reduce Vairimorpha spp. infection severity and improve bee lifespan. In a controlled experiment, foraging bees were divided into groups of infected and uninfected individuals, and each group (N = 50) was exposed to varying ethanol concentrations (0%, 0.0313%, 0.625%, 1.25%, 2.5%, 5%, and 10%). The results indicated that infected bees exposed to 0.625% and 1.25% ethanol exhibited the longest lifespans and the lowest Vairimorpha (Nosema) spp. spore counts, supporting the hormetic model. In contrast, higher ethanol concentrations (2.5% and above) significantly increased mortality and spore load, reaffirming the toxic effects associated with excessive ethanol intake. This study highlights the complex interactions between ethanol exposure and parasitic infection in honeybees, suggesting that ethanol at 0.625% and 1.25% may mitigate some of the harmful effects of Vairimorpha (Nosema) spp. infections. The findings have implications for understanding how ethanol, present in floral nectar, impacts honeybee health and could inform management strategies for controlling Vairimorpha (Nosema) spp. infections in bee populations. Full article

The consumption of edible flowers has gained increasing global attention, driven by the demand for natural and functional foods. Edible flowers are consumed in various forms, including fresh, dried, or as ingredients in derived products such as infusions, dietary supplements, and honey. Their growing popularity is associated not only with their ability to enhance sensory properties, such as aroma, color, and flavor, but also with their potential health-promoting effects. Nevertheless, their consumption entails safety concerns related to possible contamination with pesticide residues, heavy metals, insects, microorganisms, and naturally occurring toxic compounds. Among these, tropane alkaloids (TAs) and pyrrolizidine alkaloids (PAs) represent major toxicological concerns. These alkaloids may be detected even in non-producing species due to cross-contamination in the field, horizontal transfer through soil, or pollination by bees that have previously visited TA- or PA-producing plants. This review addresses the risks associated with the consumption of edible flowers and flower-derived products, with particular emphasis on studies published since 2018. It provides an overview of the occurrence of TAs and PAs in fresh flowers, floral infusions, dietary supplements, and honey. Furthermore, it summarizes the analytical methodologies employed, including sample preparation and detection techniques, and compiles the reported concentrations of these alkaloids. The evidence presented highlights the need for continued investigation to establish reliable risk assessments and ensure consumer safety. Full article

Tea oil tree (Camellia oleifera), a woody oil crop native to Southern China, relies on insect pollination for fruit and seed production. However, its nectar is toxic to honey bees (Apis spp.) due to their inability to digest the oligosaccharide present in the nectar. This toxicity raises concerns about the trade-off between the benefits of pollination and the risks posed by exposures to toxic nectar. We aimed to investigate whether tea oil tree yield is enhanced by honey bee pollination, while also examining the impact of nectar toxicity and exploring potential mitigation methods. We evaluated the fruit set, seed yield, and oil quality of the crop with or without eastern honey bee (A. cerana) pollination during 2019–2022. We also characterized nectar oligosaccharide compositions collected from both flowers and bee hives. We administered α-galactosidase (an enzyme to promote oligosaccharide digestion) onto bee larvae fed with crop nectar. We found that A. cerana could significantly enhance fruit set and seed yield. The administration of α-galactosidase could enhance larval survivorship challenged by nectar toxicity. The effectiveness of honey bee pollination can vary between years, with warmer temperatures significantly enhancing honey bee pollination benefits. The results suggest that a decision to use honey bees for pollinating tea oil trees should involve consideration of the impact of local weather conditions, as low temperatures may compromise pollination benefits while increasing risks posed by toxic nectar. The administration of digestive enzymes to honey bees shows potential for mitigating natural toxins in tea oil tree nectar. Full article

This study developed a gas chromatography–tandem mass spectrometry (GC-MS/MS) method for detecting dinotefuran residues in fruits and vegetables. The modified extraction procedure employed solvent conversion for GC-MS/MS compatibility, achieving a linear range of 0.001–2.0 mg/kg (r² > 0.999), a LOD of 0.003 mg/kg, and a LOQ of 0.01 mg/kg. Recovery rates ranged from 88.2% to 104.5% (RSD: 3.5–5.8%). The analysis of 18 commercial samples from Weifang, China, revealed the highest residues in nectarines (0.12 mg/kg) and lowest residues in cucumbers (0.02 mg/kg), with the dietary exposure risk assessment indicating hazard quotients well below safety thresholds. The literature review showed that dinotefuran has a shorter soil half-life (10–30 days) than most neonicotinoids, a low adsorption coefficient (Koc 30–50), high leaching potential, and significant toxicity to pollinators (LD₅₀ = 0.023 μg/bee). The validated method provides reliable detection across diverse matrices, while the environmental behavior analysis highlights the need for the careful management of dinotefuran applications to minimize ecological impacts despite its favorable degradation profile compared to other neonicotinoids. Full article

Propolis, also known as bee glue, is a natural resinous mixture produced by Western honeybees and has long been recognized for its potential therapeutic properties. Recent research has focused on its diverse bioactivities, particularly its antimicrobial effects against a broad spectrum of microorganisms, including human but also animal pathogens. However, further investigation is required to fully elucidate the pharmacological properties and potential toxicity of propolis to support its broader application. This study investigated the antimicrobial efficacy and safety of an ethanol extract of Portuguese propolis collected from the Gerês region (G23.EE). The antimicrobial activity was assessed in vitro against both Gram-positive and Gram-negative bacteria associated with infections in companion animals, using the agar dilution method. To evaluate potential toxicity, the extract was administered via injection and topical application in an in vivo Galleria mellonella larval model, with health parameters monitored over a 96 hours period. The in vitro results showed that G23.EE was more effective against Gram-positive bacteria, including Staphylococcus spp. (e.g., S. felis, S. hominis, S. simulans, and S. pseudintermedius; MIC = 0.5 mg/mL) and Enterococcus faecium (MIC = 1.5 mg/mL), than against Gram-negative bacteria, such as Escherichia coli and Klebsiella oxytoca (MIC > 8.0 mg/mL). No significant adverse effects were observed in G. mellonella larvae following injection or brushing with propolis extract concentrations up to 8.0 mg/mL. Overall, these findings suggest that Portuguese propolis from Gêres is a promising, safe, and effective natural antimicrobial agent for targeting Gram-positive bacterial infections in companion animals. 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

Varroa destructor represents a major threat to honeybee colonies worldwide, prompting the search for alternative organic acaricides. This study evaluated the biological activity of essential oils extracted from three Patagonian wild plants—Adesmia boronioides, Dysphania multifida, and Senecio filaginoides—on both V. destructor and Apis mellifera. Chemical analysis revealed that A. boronioides oil was dominated by esquelenone (34.49%), D. multifida by ascaridole (34.87%), and S. filaginoides by α-pinene (40.87%). All essential oils exhibited acaricidal activity, with D. multifida showing the lowest LC₅₀ against V. destructor (1.1 µL/mL at 24 h). Toxicity assays on adult bees indicated that A. boronioides and D. multifida significantly reduced bee survival, whereas S. filaginoides did not appear to cause significant mortality (LC₅₀ = 139.5 µL/mL). Repellency tests for A. boronioides and D. multifida showed significant mite repellence. Larval assays revealed a high survival rate under S. filaginoides treatment (survival rate > 80.24%), in contrast to the reduced viability observed with the other oils. The high selectivity index of S. filaginoides underscores its potential as a selective and safe botanical acaricide. Moreover, its LC₅₀ decreased over time, suggesting a residual acaricidal effect. These findings support S. filaginoides as a promising candidate for sustainable V. destructor control. Full article