OBJECTIVE: The goal of the current study was to clarify the potential molecular mechanism underlying the protective effects of silymarin (SIL) administration against diazinon-induced subacute nephrotoxicity, with a special emphasis on the role of the Kelch-like-associated protein-1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2)-heme oxygenase-1 (HO-1) signaling pathway in minimizing the oxidative stress induced by diazinon (DZN).
METHODS: Five equal groups of thirty adult male Wistar rats were created at random. Group 1 (G1) was maintained under typical control conditions and administered saline intragastrically (I/G) once daily for 4 weeks; G2 was administered olive oil I/G for 4 weeks; G3 was I/G administered silymarin daily for 4 weeks; G4 was I/G administered diazinon daily for 4 weeks. G5 was I/G administered silymarin daily 1 h before the I/G administration of the diazinon for 4 weeks. Blood samples were collected at the end of the experiment for the determination of complete blood cell count, and kidney function tests. Kidney specimens were collected for the evaluation of the oxidative markers, mRNA gene expression, protein markers, and histopathological examination.
RESULTS: SIL reduced the renal dysfunction caused by DZN by restoring urea and creatinine levels, as well as oxidative indicators. Although the expression of Keap-1 was also elevated, overexpression of Nrf2 also enhanced the expression of HO-1, a crucial target enzyme of Nrf2.
CONCLUSIONS: SIL is hypothesized to potentially aid in the prevention and management of nephrotoxicity caused by DZN.

Polysialylated neural cell adhesion molecule (PSA-NCAM) is expressed in the developing central nervous system (CNS) and plays an important role in neurogenesis. Organophosphorus (OP) toxins, including diazinon (DZN), cause oxidative stress (OS) and damage the CNS. Resveratrol (RV), with its antioxidant effect, leads to the reduction of OS. Therefore, this research was conducted with the aim of the effect of RVon the expression of PSA-NCAM in the hippocampus (HPC) of rat fetuses treated with DZN. In this study, 24 female Wistar rats were divided into 4 groups (n = 6): Control, DZN (40 mg/kg), RV(10 mg/kg), and DZN + RV(40 mg/kg + 10 mg/kg) after confirming they were pregnant. On the 21st day of pregnancy, the mother mice were anesthetized with ketamine and xylazine, and the fetuses were removed; after anesthesia, their brains were removed for immunohistochemistry and western blot (WB) technique. The results of the study showed that in the group receiving DZN, the level of PSA-NCAM protein expression decreased significantly compared to the control group, and the group receiving RV with its antioxidant property increased the expression of PSA-NCAM protein compared to the DZN group. All in all, the exposure of pregnant mice to DZN causes disorders in the CNS, especially the level of PSA-NCAM protein expression in the HPC of fetuses, and the use of RV as an antioxidant by pregnant mothers neutralizes the effects of DZN in the HPC of their fetuses.

Diazinon is an organophosphorus (OP) insecticides used in agriculture, home gardening and indoor pest control in Japan. It can activate macrophages and induce pro-inflammatory responses and has been reported to cause airway hyper-reactivity, suggesting the possibility of asthma exacerbation from exposure to OP insecticides. Despite the correlation between insecticide use and the pathogenesis of allergic diseases, there have been no reports on the effects of diazinon on mast cell function. Therefore, in this study, we investigated the effects of diazinon on mast cell function in rat basophilic leukemia (RBL)-2H3 cells. Surprisingly, we found that diazinon inhibited mast cell activation, although the degree of inhibition varied with concentration. Diazinon induced reactive oxygen species (ROS) generation and HO-1 expression at a concentration of 150 µM without affecting cell viability. Diazinon inhibited A23187-mediated degranulation and Tnf and Il4 expression in RBL-2H3 cells but did not affect calcium influx. Suppression of degranulation by diazinon was reversed when the culture supernatant was removed. As a signaling event downstream of calcium influx, diazinon inhibited the phosphorylation of extracellular signal-regulated kinase (ERK) induced by A23187, whereas the phosphorylation of p38 had little effect. IgE cross-linking-mediated degranulation as well as the induction of Tnf and IL4 expression was significantly inhibited by diazinon, while diazinon had little effect on calcium influx. In conclusion, diazinon inhibited mast cell activation, including degranulation and cytokine expression. When evaluating the in vivo effects of diazinon, its potential to inhibit mast cell activation should be considered in the pathophysiology and development of allergic diseases in terms of basic and clinical aspects, respectively, although the effect of diazinon varies depending on the cell type.

Diazinon is an organophosphorus pesticide widely used in agriculture and household pest control, and its use also poses several environmental and health hazards. In this study, we investigated the spatial and temporal distribution of diazinon in Baiyangdian, evaluated its potential ecological risk and toxicity to aquatic organisms based on RQ (Risk quotient) and TU (Toxic unit) analysis, and assessed the potential effects of diazinon accumulation on probiotics and pathogens based on statistical analysis of high-throughput sequencing data. The results showed that diazinon in Baiyangdian posed a low to moderate chronic risk to sediment-dwelling organisms and a low toxicity effect on aquatic invertebrates, which was mainly concentrated in October and human-intensive areas. Meanwhile, increases in sediment electrical conductivity (EC), amorphous iron oxides content and phenol oxidase activity favored diazinon accumulation in sediments, whereas the opposite was the case for sediment organic carbon, β-1,4-glucosidase, phosphatase, catalase and pH, suggesting that environmental indicators play a key role in the behavior and distribution of diazinon. In addition, diazinon in heavily contaminated areas seem to inhibit the rare probiotics (Bifidobacterium adolescentis and Serratia sp.), while promoted dominant pathogens (e.g., Burkholderia cenocepacia), which can lead to increased disease risk to humans and ecosystems, disruption of ecological balance and potential health problems. However, probiotic Streptomyces xiamenensis resist to diazinon would be a potential degrader for diazinon remove. In conclusion, this study unveiled the effects of diazinon pollution on wetland ecosystems, emphasizing ecological impacts and potential health concerns. In addition, the discovery of diazinon resistant probiotics provided new insights into wetland ecological restoration.

Diazinon, an organophosphorus insecticide, is predominantly removed through photodegradation and biodegradation in the environment. However, photodegradation can generate diazoxon, a highly toxic oxidation byproduct, while biodegradation is hard to complete mineralize diazinon, showing limitations in both methods. In this study, we provided an efficient strategy for the complete and harmless removal of diazinon by synergistically employing biodegradation and photodegradation. The diazinon-degrading strain X1 was capable of completely degrading 200 μM of diazinon into 2-isopropyl-6-methyl-4-pyrimidinol (IMP) within 6 h without producing the highly toxic diazoxon. IMP was the only intermediate metabolite in biodegradation process, which cannot be further degraded by strain X1. Through RT-qPCR and prokaryotic expression analyses, the hydrolase OpdB was pinpointed as the key enzyme for diazinon degradation in strain X1. Photodegradation was further used to degrade IMP and a pyridazine ring-opening product of IMP was identified via high resolution mass spectrometry. The acute toxicity of this product to aquatic organisms were 123 times and 6630 times lower than that of diazinon and IMP, respectively. The stepwise application of biodegradation and photodegradation was proved to be a successful approach for the remediation of diazinon and its metabolite IMP. This integrated method ensures the harmless and complete elimination of diazinon and IMP within only 6 h. The research provides a theoretical basis for the efficient and harmless remediation of organophosphorus insecticide residuals in the environment.

Stable detection of diazinon (DZN) residues in vegetables is important for food safety. In this work, an electrochemiluminescence (ECL) aptasensor with dual-catalytic glucose in-situ production of H2O2 was constructed for the stable detection of DZN in vegetables. Firstly, MWCNTs@MB was prepared using π-π stacking interactions between methylene blue (MB) and multi-walled carbon nanotubes (MWCNTs) to enhance the loading of MB on an electrode and thus catalyze the generation of H2O2 from glucose. Secondly, Cu2O@AuNPs was formed by loading AuNPs on the surface of Cu2O through spontaneous reduction reaction, which improved the interfacial charge transfer, Cu2O nano-enzyme had glucose oxidase mimicking activity and could further catalyze the production of more H2O2 from glucose. MWCNTs@MB and Cu2O@AuNPs played a key role in the in-situ generation of co-reacting reagent H2O2, which solved the problem of unstable detection caused by the easy decomposition of the H2O2 solution added to the luminescence system. In addition, the aptamer was immobilized on the electrode surface by forming Au-S bonds with Cu2O@AuNPs. As a result, the ECL aptasensor performed good linearity in 1.00 pg mL-1-1.00 μg mL-1 and a low limit of detection (LOD) to 0.39 pg mL-1 (S/N = 3). This work provided an effective method for the accurate and stable detection of DZN residues in vegetables, which was of great significance in ensuring food safety and assessing the environmental risk of DZN.

Human impacts on ecological communities are pervasive and species must either move or adapt to changing environmental conditions. For environments polluted by contaminants, researchers have found hundreds of target pest species evolving increased tolerance, but we have substantially fewer cases of evolved tolerance in non-target species. When species do evolve increased tolerance, inducible tolerance can provide immediate protection and favor the evolution of increased tolerance over generations via genetic assimilation. Using a model larval amphibian (wood frogs, Rana sylvatica), we examined the tolerance of 15 populations from western Pennsylvania and eastern New York (USA), when first exposed to no pesticide or sublethal concentrations and subsequently exposed to lethal concentrations of three common insecticides (carbaryl, chlorpyrifos, and diazinon). We found high variation in naïve tolerance among the populations for all three insecticides. We also discovered that nearly half of the populations exhibited inducible tolerance, though the degree of inducible tolerance (magnitude of tolerance plasticity; MoTP) varied. We observed a cross-tolerance pattern of the populations between chlorpyrifos and diazinon, but no pattern of similar MoTP among the pesticides. With populations combined from two regions, increased tolerance was not associated with proximity to agricultural fields, but there were correlations between proximity to agriculture and MoTP. Collectively, these results suggests that amphibian populations possess a wide range of naïve tolerance to common pesticides, with many also being able to rapidly induce increased tolerance. Future research should examine inducible tolerance in a wide variety of other taxa and contaminants to determine the ubiquity of these responses to anthropogenic factors.

Compound-specific isotope analysis stands as a promising tool for unveiling the behavior of pesticides in agricultural environments. Using the commercial formulations of persistent fungicide procymidone (PRO) and less persistent insecticide diazinon (DIA), respectively, we analyzed the concentration and carbon isotope composition (δ13C) of the residual pesticides through soil incubation experiments in a greenhouse (for 150 days) and lab conditions (for 50-70 days). Our results showed that the magnitude of δ13C variation depends on pesticide specificity, in which PRO in the soil exhibited little variation in δ13C values over the entire incubation times, while DIA demonstrated an increased δ13C value, with the extent of δ13C variability affected by different spiking concentrations, plant presence, and light conditions. Moreover, the pesticides extracted from soils were isotopically overlapped with those from crop lettuce. Ultimately, the isotope composition of pesticides could infer the degradation and translocation processes and might contribute to identifying the source(s) of pesticide formulation in agricultural fields.

Diazinon (DZN) is a member of organophosphorus insecticides that has cytotoxic effects on different organs. n-Acetyl cysteine (NAC) is a widely used antioxidant in clinical, in vivo and in vitro studies. We evaluated the protective role of NAC against DZN-induced toxicity in kidney tissue of Wistar rats. 30 male Wistar rats were divided into 5 groups of control, single dose of DZN, continuous dose of DZN, single doses of DZN + NAC and continuous doses of DZN + NAC. Kidney function test (blood urea nitrogen, creatinine and uric acid) was provided. Levels of malondialdehyde (MDA), total antioxidant capacity (TAC) and total sulfhydryl (T-SH) were determined in renal tissues. Renal cells apoptosis was detected using TUNEL assay. The mRNA expressions of apoptosis, oxidative stress and inflammatory mediators, including B-cell lymphoma-2 (Bcl2), Bcl-2-associated X protein (Bax), superoxide dismutase (SOD), catalase (CAT), Interleukin 10 (IL-10), Tumor necrosis factor-α (TNF-α), Caspase-3 and Caspase-8 were analyzed in kidney tissues using Real Time PCR method. Chronic exposure to DZN was associated with severe morphological changes in the kidney, as well as impairment of its function and decreased kidney weights. Continues treatment with DZN significantly decreased the percentage of renal apoptotic cells as compared to rats treated with continuous dose of DZN alone (17.69 ± 3.67% vs. 39.46% ± 2.44%; p < 0.001). Continuous exposure to DZN significantly decreased TAC and T-SH contents, as well as SOD and CAT expression, but increased MDA contents in the kidney tissues (p < 0.001). A significant increase was observed in mRNA expression of Bax, Caspase-3, Caspase-8, as well as TNF-α following exposure to DZN, but the expression of IL-10 and Bcl2 was significantly decreased. NAC can protect kidney tissue against DZN-induced toxicity by elevating antioxidants capacity, mitigating oxidative stress, inflammation and apoptosis.

In this work, a simple synthesis of low-toxicity transition metal material of WO3-x dots was used as a co-reactant with Au@SiO2 as a core-shell material and a signal amplification factor to collaboratively promote Ru(bpy)32+ electrochemiluminescence (ECL) for the construction of a highly sensitive aptasensor for the detection of diazinon (DZN) in vegetables. Electrodes modified with multi-walled carbon nanotubes-chitosan composite membranes (MWCNTs-CS) were used to load and immobilize more Ru(bpy)32+.can load more Ru(bpy)32+. WO3-x dots synthesized by a simple method showed excellent ECL efficiency as a novel co-reactant for Ru(bpy)32+. Under optimized conditions, this aptasensor for DZN has a wide detection range (10 pg mL-1 - 1 μg mL-1.) and a low detection limit (0.0197 ng L-1). The aptasensor has shown good results in the analysis of real samples in the experiment. This work provides a new approach to the construction of a novel electrochemiluminescence sensor for the detection of pesticides.