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Antioxidants (Basel, Switzerland) Nov 2023Exposure to phoxim at low levels caused bioaccumulation with neurotoxicity but also induced oxidative stress, tissue damage, and abnormal nutrient metabolism. This study...
Exposure to phoxim at low levels caused bioaccumulation with neurotoxicity but also induced oxidative stress, tissue damage, and abnormal nutrient metabolism. This study described that vitamin E ameliorates phoxim-induced nephrotoxicity via inhibiting mitochondrial apoptosis. In vivo, 24 healthy piglets were treated with phoxim (0 mg/kg and 500 mg/kg) and vitamin E + phoxim (vitamin E + phoxim: 200 mg/kg + 500 mg/kg). In vitro, PK15 cells were treated with phoxim (0 mg/L and 1 mg/L) and vitamin E + phoxim (phoxim + vitamin E: 1 mg/L + 1 mg/L) for 12 h and 24 h. Our results indicated that accumulation of ROS, oxidative stress, and renal cell injury through stimulation of mitochondrial apoptosis resulted in phoxim-induced nephrotoxicity. Phoxim resulted in swollen mitochondria, blurred internal cristae, renal glomerular atrophy, and renal interstitial fibrosis. Vitamin E alleviated the adverse effects of phoxim by reducing ROS and improving antioxidant capacity in vivo and in vitro. Vitamin E significantly increased SDH in vitro ( < 0.01), while it decreased ROS, Bad, and cyto-c in vitro and SOD and CAT in vivo ( < 0.05). Vitamin E ameliorated phoxim-induced renal histopathologic changes, and mitochondria swelled. In addition, vitamin E regulates phoxim-induced apoptosis by alleviating oxidative damage to the mitochondria.
PubMed: 38001853
DOI: 10.3390/antiox12112000 -
Environmental Pollution (Barking, Essex... Apr 2020Phoxim, a broad-spectrum organophosphate pesticide, is widely used in agriculture to control insect pests in vegetable crops as well as in farm mammals. However, the...
Phoxim, a broad-spectrum organophosphate pesticide, is widely used in agriculture to control insect pests in vegetable crops as well as in farm mammals. However, the indiscriminate use of phoxim has increased its release into the environment, leading to the contamination of plant-based foods such as vegetables. In this study, we investigated the effect of Trichoderma asperellum (TM, an opportunistic fungus) on phoxim residue in tomato roots and explored the mechanisms of phoxim metabolism through analysis of detoxification enzymes and gene expression. Degradation kinetics of phoxim showed that TM inoculation rapidly and significantly reduced phoxim residues in tomato roots. Phoxim concentrations at 5d, 10d and 15d post treatment were 75.12, 65.71 and 77.45% lower in TM + phoxim than only phoxim treatment, respectively. The TM inoculation significantly increased the glutathione (GSH) content, the activity of glutathione S-transferase (GST) and the transcript levels of GSH, GST1, GST2 and GST3 in phoxim-treated roots. In addition, the activity of peroxidase and polyphenol peroxidase involved in the xenobiotic conversion also increased in TM + phoxim treatment. The expression of detoxification genes, such as CYP724B2, GR, ABC2 and GPX increased by 3.82, 3.08, 7.89 and 2.46 fold, respectively in TM + phoxim compared with only phoxim. Similarly, the content of ascorbate (AsA) and the ratio of AsA to dehydroascorbate increased by 45.16% and 57.34%, respectively in TM + phoxim-treated roots. Our results suggest that TM stimulates plant detoxification potential in all three phases (conversion, conjugation and sequestration) of xenobiotc metabolism, leading to a reduced phoxim residue in tomato roots.
Topics: Animals; Environmental Restoration and Remediation; Solanum lycopersicum; Organothiophosphorus Compounds; Pesticide Residues; Plant Roots; Trichoderma
PubMed: 31918147
DOI: 10.1016/j.envpol.2019.113893 -
Environmental Science and Pollution... Sep 2022Phoxim is one of the main organophosphorus pesticides used in agricultural production. However, little information is known about how it affects the aquatic microbial...
Phoxim is one of the main organophosphorus pesticides used in agricultural production. However, little information is known about how it affects the aquatic microbial community and the intestinal microbiota of fish. Herein, we utilized shotgun metagenomics and 16S rRNA gene sequencing to reveal the aquatic eco-risk of phoxim. Seven days of phoxim exposure significantly changed the composition of aquatic microbial community, obliterated the interactions between microorganisms, and thus reduced the complexity and stability of the microbial community. During long-time exposure (i.e., 14 days), most of the ecological functions were restored due to the redundancy of the microbial community. However, phoxim exposure promoted the dissemination of elfamycin resistance gene. The zebrafish gut microbial community also recovered from a temporary ecological disorder of aquatic microbiota, but phoxim continually affected zebrafish growth and swimming behavior. Overall, our results demonstrated that phoxim exposure significantly changed the structure and function of the microbial community and displayed a negative impact on freshwater ecosystems in a short exposure time.
Topics: Animals; Gastrointestinal Microbiome; Genes, rRNA; Metagenomics; Microbiota; Organophosphorus Compounds; Organothiophosphorus Compounds; Pesticides; RNA, Ribosomal, 16S; Zebrafish
PubMed: 35449330
DOI: 10.1007/s11356-022-20325-8 -
Pesticide Biochemistry and Physiology Mar 2020Silkworm (Bombyx mori) is an important economic insect. Bombyx mori, which is exposed to sublethal doses of pesticides, has a low or no mortality rate, while it is...
Silkworm (Bombyx mori) is an important economic insect. Bombyx mori, which is exposed to sublethal doses of pesticides, has a low or no mortality rate, while it is susceptible to infections triggered by foreign pathogens. The immune regulatory mechanism of silkworms caused by trace pesticides still remains unclear. The midgut is the major organ of silkworm for digestion and nutrient absorption, and it plays a critical defensive role against pathogens. In the present study, the silkworm was susceptible to Enterobacter cloacae sp. (E. cloacae) after exposure to sublethal dose of phoxim. The body weight and survival rate of the phoxim-E. cloacae co-treatment group were significantly decreased after 120 h of treatment compared with the phoxim treatment group. The immune responses and expressions of immune-related genes were dysregulated in the midgut of silkworm following exposure to phoxim. Digital gene expression (DGE) analysis revealed that 44 immune response-related and immune defense-related genes were differentially expressed. qRT-PCR results indicated that the transcriptional levels of antimicrobial peptide genes Bmdefensin1, BmcecA, Bmglv1, Bmglv2, Bmmoricin and BmmoricinB3 were down-regulated by 0.77-, 0.37-, 0.05-, 0.19-, 0.34- and 0.54-fold, respectively. The transcriptional levels of Toll signaling pathway genes Bmcactus, Bmspatzle and Bmrel were down-regulated by 0.4-, 0.37- and 0.96-fold, respectively. Peritrophic membrane (PM) protein-related genes BmCBP-02, BmPM-41, BmPM-43 and BmCDA7 were down-regulated by 0.18-, 0.02-, 0.66- and 0.16-fold, respectively. The expressions of Toll signaling pathway genes were down-regulated at 48 h and 72 h. Immune deficiency (IMD) and Janus kinase and signal transducer and activator of transcription (JAK/STAT) signaling pathway genes were dysregulated after phoxim exposure. These results indicated that phoxim might cause damage to the PM and reduce the immune response of the silkworm, leading to susceptibility of silkworm to disease and damage from foreign pathogens.
Topics: Animals; Bombyx; Immune System; Insect Proteins; Insecticides; Organothiophosphorus Compounds; Pesticides
PubMed: 32284137
DOI: 10.1016/j.pestbp.2019.12.007 -
Environmental Science and Pollution... Aug 2022With continuous development of pesticide dosage forms, emulsifiable concentrates using large amounts of organic solvents are gradually obsoleted. Nanoemulsions with high...
With continuous development of pesticide dosage forms, emulsifiable concentrates using large amounts of organic solvents are gradually obsoleted. Nanoemulsions with high water content have been developed and the preparation processes also evolved, but these processes still exist some problems, such as poor controllability and high energy consumption. Microfluidic is a controllable nanoemulsion preparation system which mainly applied to pharmaceutical synthesis. In this study, the pesticide phoxim nanoemulsion was prepared by microfluidic technology. The optimized formulation of phoxim nanoemulsion was composed of Tween 80 and pesticide emulsifier 500 as surfactant, hexyl acetate as oil, and n-propanol as co-surfactant. Moreover, when the flow rates of water and oil in the microfluidic system were adjusted to 5 μL/min and 20 μL/min, phoxim nanoemulsion was obtained with a cloud point/boiling point of 109 °C, a particle size of 21.5 ± 0.8 nm and a potential value of - 18.7 ± 0.6 mV. Furthermore, the nanoemulsion had a rapid release effect in vitro which could be fitted by the Ritger-Peppas model. The feeding toxicity of the phoxim nanoemulsion was higher than that of commercial formulation while the contact killing effect was higher than that of the active ingredient. Therefore, pesticide dosage was reduced and the insecticidal effect was enhanced by using phoxim nanoemulsions. These results also confirm the potential of microfluidics as a green process to produce pesticide nanoemulsions.
Topics: Animals; Emulsions; Microfluidics; Organothiophosphorus Compounds; Particle Size; Pesticides; Spodoptera; Surface-Active Agents; Water
PubMed: 35394625
DOI: 10.1007/s11356-022-20001-x -
Ecotoxicology and Environmental Safety Feb 2020Organophosphate pesticides are widely applied worldwide for agricultural purposes, and their exposures often result in adverse effects on Bombyx mori. The insect gut is...
Organophosphate pesticides are widely applied worldwide for agricultural purposes, and their exposures often result in adverse effects on Bombyx mori. The insect gut is a complicated ecosystem inhabited by a large number of microbes that play important roles in insect physiology and behavior. Recent studies have reported that alteration of their microbiota due to stressful conditions or environmental changes has been linked to a compromised health status and a susceptibility to diseases. In the present study, we aimed to assess the effects of phoxim exposure on intestinal microbes in silkworms. The results showed that phoxim exposure increased the bacterial community evenness and altered the structure of gut microbiota in silkworm larvae. The abundances of several genera, such as Methylobacterium and Aurantimonadaceae, in phoxim-treated larval guts were significantly reduced compared with the HO-treated group, whereas the abundances of non-dominant bacteria, such as Staphylococcus, were significantly increased. Moreover, phoxim inhibited the expressions of antimicrobial peptides (AMPs) at the mRNA level and enhanced the pathogenesis of Enterobacter cloacae (E. cloacae) against silkworm larvae, suggesting that the immune system was inhibited after phoxim exposure. Therefore, the gut microbial community shifts were apparent after phoxim exposure. The compositional and structural changes of intestinal microbes caused by phoxim exposure might affect the normal function of the intestinal tract of silkworm. These results highlighted the importance of the gut bacterial community when investigating the mechanisms of midgut injury after pesticide exposure in Bombyx mori.
Topics: Animals; Antimicrobial Cationic Peptides; Bacteria; Bombyx; Gastrointestinal Microbiome; Gene Expression; Insect Proteins; Insecticides; Intestines; Larva; Organothiophosphorus Compounds
PubMed: 31796255
DOI: 10.1016/j.ecoenv.2019.110011 -
Fish & Shellfish Immunology Jul 2024The efficacy of phoxim in treating bacterial sepsis in silver carp is significant, yet its underlying mechanism remains elusive. This study aimed to establish a model of...
The efficacy of phoxim in treating bacterial sepsis in silver carp is significant, yet its underlying mechanism remains elusive. This study aimed to establish a model of Aeromonas veronii infection in silver carp and subsequently treat the infected fish with 10 μg/L phoxim. Kidney and intestine samples from silver carp were collected for transcriptome analysis and assessment of intestinal microbial composition, with the aim of elucidating the mechanism underlying the efficacy of phoxim in treating bacterial sepsis in silver carp. The results of transcriptome and intestinal microbial composition analysis of silver carp kidney indicated that A. veronii infection could up-regulate the expression of il1β, il6, nos2, ctsl, casp3 et al., which means, signifying that the kidney of silver carp would undergo inflammation, induce apoptosis, and alter the composition of intestinal microorganisms. Phoxim immersion might enhance the energy metabolism of silver carp and change its intestinal microbial composition, potentially elevating the antibacterial infection resistance of silver carp. These findings may contribute to an understanding of how phoxim can effectively treat bacterial sepsis in silver carp.
Topics: Animals; Carps; Fish Diseases; Organothiophosphorus Compounds; Gram-Negative Bacterial Infections; Aeromonas veronii; Gastrointestinal Microbiome
PubMed: 38750706
DOI: 10.1016/j.fsi.2024.109628 -
Journal of Agricultural and Food... Dec 2023The black cutworm is a serious crop pest. Phoxim, an organophosphorus insecticide, has been widely used to control . When phoxim is extensively applied, the...
The black cutworm is a serious crop pest. Phoxim, an organophosphorus insecticide, has been widely used to control . When phoxim is extensively applied, the susceptibility of to insecticide is reduced. However, the mechanisms of tolerance of to phoxim remain unclear. Herein, we report that an epsilon class glutathione -transferase, AiGSTE1, confers phoxim tolerance in . Exposure to a sublethal concentration (LC) of phoxim caused oxidative stress and activated the transcription of genes in larvae. Recombinant AiGSTE1 expressed in could metabolize phoxim. Furthermore, cells overexpressing AiGSTE1 displayed significant tolerance to oxidative stress. Knockdown of by RNA interference significantly increased the mortality of larvae to phoxim. These results demonstrate that AiGSTE1 confers phoxim tolerance in by metabolizing the insecticide and preventing phoxim-induced oxidative stress.
Topics: Animals; Lepidoptera; Insecticides; Escherichia coli; Organophosphorus Compounds; Moths; Larva
PubMed: 38088263
DOI: 10.1021/acs.jafc.3c07964 -
The Science of the Total Environment Sep 2024The presence of certain associated bacteria has been reported to increase pest resistance to pesticides, which poses a serious threat to food security and the...
The presence of certain associated bacteria has been reported to increase pest resistance to pesticides, which poses a serious threat to food security and the environment. Researches on the above microbe-derived pesticide resistance would bring innovative approaches for pest management. Investigations into the phoxim resistance of Delia antiqua, one Liliaceae crop pests, revealed the contribution of a phoxim-degrading gut bacterium, D39, to this resistance. However, how the strain degraded phoxim was unknown. In this study, the role of D39 in phoxim degradation and resistance was first confirmed. DT, which had an identical taxonomy but lacked phoxim-degrading activity, was analyzed alongside D39 via comparative genomics to identify the potential phoxim degrading genes. In addition, degradation metabolites were identified, and a potential degradation pathway was proposed. Furthermore, the main gene responsible for degradation and the metabolites of phoxim were further validated via prokaryotic expression. The results showed that D39 contributed to resistance in D. antiqua larva by degrading phoxim. Phoxim was degraded by an enzyme encoded by the novel gene phoD in D39 to O,O-diethyl hydrogen phosphorothioate and 2-hydroxyimino-2-phenylacetonitrile. Finally, downstream products were metabolized in the tricarboxylic acid cycle. Further analysis via prokaryotic expression of phoD confirmed its degradation activity. The mechanisms through which gut microbes promote pesticide resistance are elucidated in this study. These results could aid in the development of innovative pest control methods. In addition, this information could also be used to identify microbial agents that could be applied for the remediation of pesticide contamination.
Topics: Organothiophosphorus Compounds; Gastrointestinal Microbiome; Insecticides; Animals; Insecticide Resistance; Inactivation, Metabolic; Bacteria
PubMed: 38862045
DOI: 10.1016/j.scitotenv.2024.173866 -
Protective effects of pretreatment with Fe, Cu, and Rb on phoxim poisoning in silkworm, Bombyx mori.Journal of Trace Elements in Medicine... Dec 2021Phoxim is a widely used organophosphorus pesticide in agriculture. People are paying more and more attention to its toxicity. At present, there is no appropriate way to...
BACKGROUND
Phoxim is a widely used organophosphorus pesticide in agriculture. People are paying more and more attention to its toxicity. At present, there is no appropriate way to solve the phoxim poisoning of silkworm, which severely affected the development of sericulture. Fe, Cu, Rb exerted their biological effects through various forms in vivo.
METHODS
To evaluate the effect of Fe/Cu/Rb on phoxim poisoning in silkworm, Bombyx mori were treated with fresh mulberry leaves soaked in 2.5 mg/L phoxim for 2 min with 50 mg/L FeCl, 150 mg/L CuCl, or 0.5 mg/L RbCl from 5 days of the fifth-instar silkworm.
RESULTS
Fe, Cu, and Rb pretreatments significantly inhibited the phoxim-induced reduction of survival rate and alleviated the phoxim-induced poisoning symptoms. The protective effects of Fe, Cu, and Rb on phoxim poisoning might be due to their enhancement of superoxide dismutase (SOD), catalase (CAT), and carboxylesterase (CarE) in the hemolymph and fat body of silkworm. This enhancement might reduce reactive oxygen species (ROS) accumulation and oxidative stress (OS) caused by phoxim poisoning. Thereby it reduced the damage to silkworm tissues and cells.
CONCLUSIONS
These results showed that Fe, Cu, and Rb treatments protected the silkworm from phoxim poisoning by directly enhancing the activity of SOD, CAT, and CarE enzymes and reducing oxidative stress, but not dependent on the high expression of CYP genes. The use of Fe, Cu, and Rb to enhance the activity of SOD, CAT, and CarE enzymes may be an underlying effective way to solve phoxim poisoning in the silkworm industry.
Topics: Animals; Bombyx; Insecticides; Organophosphorus Compounds; Organothiophosphorus Compounds; Pesticides; Superoxide Dismutase
PubMed: 34425455
DOI: 10.1016/j.jtemb.2021.126844