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1.
Molecules ; 29(14)2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39064940

ABSTRACT

This study evaluated the residue behavior and dissipation dynamics of a new imidacloprid FS 600 seed treatment in potato cultivation systems in Shandong and Jilin, China. Sensitive and accurate UPLC-MS/MS methods were established to quantify imidacloprid residues in potatoes, potato plants, and soil. Results showed that imidacloprid dissipation followed a first-order kinetic model, with half-lives ranging from 6.9 to 26.7 days in plants and 19.8 to 28.9 days in soil. At harvest, the highest average residues in potatoes and soil were 0.778 mg/kg and 0.149 mg/kg, respectively. The dietary risk assessment indicated a chronic risk quotient (CRQ) of 39.73% for adults, indicating minimal risk to human consumers, while the ecological risk quotient (ERQ) and ecotoxicity exposure ratio (TER) revealed low to moderate toxicity to earthworms, warranting caution in the use of this formulation. This research provides valuable data for assessing the safety of imidacloprid FS seed treatment in potato cultivation.


Subject(s)
Neonicotinoids , Nitro Compounds , Seeds , Solanum tuberosum , Solanum tuberosum/growth & development , Solanum tuberosum/chemistry , Solanum tuberosum/drug effects , Neonicotinoids/analysis , China , Seeds/chemistry , Pesticide Residues/analysis , Tandem Mass Spectrometry , Insecticides , Soil/chemistry , Risk Assessment , Soil Pollutants/analysis , Soil Pollutants/toxicity
2.
Physiol Rep ; 12(15): e16138, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39079941

ABSTRACT

We investigated the effects of neonicotinoid pesticides (NEOs) on the spontaneous swimming and foraging behavior, as well as the morphological and physiological changes of goldfish. Most fish reared in thiamethoxam (THM)-sprayed rice fields showed the scales easily peeled off, and increased ascites. Some individuals showed decreased bio-defense activity and low plasma Ca2+. Similar changes were found in the exposure test to THM (1.0 and 20.0 µg/L) and dinotefuran (1.2 and 23.5 µg/L). Next, the effects of a low concentration of THM (1.0 µg/L) on the spontaneous swimming and foraging behavior of fish were examined. Fish exposed to THM for 1 week became restless and had increased the swimming performance, especially under natural light, white LED lighting and blue LED lighting. Goldfish exposed to THM had also increased intake of shiny white beads under green LED illumination. These results indicate that the exposure to NEO, even for a short period and at low levels, not only suppressed bio-defense activities and metabolic abnormalities, but also stress response, the swimming and foraging behavior of the fish are likely to be significantly suffered.


Subject(s)
Feeding Behavior , Goldfish , Swimming , Animals , Goldfish/physiology , Feeding Behavior/drug effects , Neonicotinoids/toxicity , Nitro Compounds/toxicity , Thiamethoxam/toxicity , Pesticides/toxicity , Oxazines/toxicity , Oxazines/pharmacology , Water Pollutants, Chemical/toxicity , Thiazoles/toxicity , Insecticides/toxicity
3.
PLoS One ; 19(7): e0305358, 2024.
Article in English | MEDLINE | ID: mdl-39008492

ABSTRACT

BACKGROUND: Huntington's disease (HD) is an extremely harmful autosomal inherited neurodegenerative disease. Motor dysfunction, mental disorder, and cognitive deficits are the characteristic features of this disease. The current study examined whether 6-shogaol has a protective effect against 3-Nitropropionic Acid (3-NPA)-induced HD in rats. METHODS: A total of thirty male Wistar rats received 6-shogaol (10 and 20 mg/kg, per oral) an hour before injection of 3-NPA (10 mg/kg i.p.) for 15 days. Behavioral tests were performed, including narrow beam walk, rotarod test, and grip strength test. Biochemical tests promoting oxidative stress were evaluated [superoxide dismutase (SOD), reduced glutathione (GSH), catalase (CAT) and malondialdehyde (MDA)], including changes to neurotransmitters serotonin (5-HT), dopamine (DA), norepinephrine (NE), homovanillic acid (HVA), (3,4-dihydroxyphenylacetic acid (DOPAC), γ-aminobutyric acid (GABA), and 5-hydroxy indole acetic acid (5-HIAA), nuclear factor kappa-B (NF-κB), tumor necrosis factor-α (TNF-α), interleukins-1ß (IL-1ß), IL-6, brain-derived neurotrophic factor (BDNF), and nuclear factor erythroid 2-related factor 2 (Nrf2). The 6-shogaol was docked to the active site of TNF-α (2AZ5), NF-κB (1SVC), BDNF) [1B8M], and Nrf2 [5FZN] proteins using AutoDock tools. RESULTS: The 6-shogaol group significantly improved behavioral activity over the 3-NPA-injected control rats. Moreover, 3-NPA-induced significantly altered neurotransmitters, biochemical and neuroinflammatory indices, which could efficiently be reversed by 6-shogaol. The 6-shogaol showed favorable negative binding energies at -9.271 (BDNF) kcal/mol. CONCLUSIONS: The present investigation demonstrated the neuroprotective effects of 6-shogaol in an experimental animal paradigm against 3-NPA-induced HD in rats. The suggested mechanism is supported by immunohistochemical analysis and western blots, although more research is necessary for definite confirmation.


Subject(s)
Brain-Derived Neurotrophic Factor , Catechols , Cytokines , Huntington Disease , Molecular Docking Simulation , NF-E2-Related Factor 2 , NF-kappa B , Nitro Compounds , Propionates , Rats, Wistar , Animals , Huntington Disease/metabolism , Huntington Disease/chemically induced , Huntington Disease/drug therapy , Propionates/pharmacology , Male , Brain-Derived Neurotrophic Factor/metabolism , Rats , NF-kappa B/metabolism , NF-E2-Related Factor 2/metabolism , Catechols/pharmacology , Catechols/chemistry , Cytokines/metabolism , Signal Transduction/drug effects , Oxidative Stress/drug effects , Behavior, Animal/drug effects , Neuroprotective Agents/pharmacology
4.
Open Biol ; 14(7): 240057, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39043224

ABSTRACT

With the spread of resistance to long-established insecticides targeting Anopheles malaria vectors, understanding the actions of compounds newly identified for vector control is essential. With new commercial vector-control products containing neonicotinoids under development, we investigate the actions of 6 neonicotinoids (imidacloprid, thiacloprid, clothianidin, dinotefuran, nitenpyram and acetamiprid) on 13 Anopheles gambiae nicotinic acetylcholine receptor (nAChR) subtypes produced by expression of combinations of the Agα1, Agα2, Agα3, Agα8 and Agß1 subunits in Xenopus laevis oocytes, the Drosophila melanogaster orthologues of which we have previously shown to be important in neonicotinoid actions. The presence of the Agα2 subunit reduces neonicotinoid affinity for the mosquito nAChRs, whereas the Agα3 subunit increases it. Crystal structures of the acetylcholine binding protein (AChBP), an established surrogate for the ligand-binding domain, with dinotefuran bound, shows a unique target site interaction through hydrogen bond formation and CH-N interaction at the tetrahydrofuran ring. This is of interest as dinotefuran is also under trial as the toxic element in baited traps. Multiple regression analyses show a correlation between the efficacy of neonicotinoids for the Agα1/Agα2/Agα8/Agß1 nAChR, their hydrophobicity and their rate of knockdown of adult female An. gambiae, providing new insights into neonicotinoid features important for malaria vector control.


Subject(s)
Anopheles , Guanidines , Insecticides , Mosquito Vectors , Neonicotinoids , Nitro Compounds , Receptors, Nicotinic , Animals , Anopheles/metabolism , Anopheles/genetics , Anopheles/drug effects , Neonicotinoids/pharmacology , Receptors, Nicotinic/metabolism , Receptors, Nicotinic/genetics , Receptors, Nicotinic/chemistry , Insecticides/pharmacology , Insecticides/chemistry , Nitro Compounds/pharmacology , Nitro Compounds/chemistry , Guanidines/pharmacology , Mosquito Vectors/drug effects , Mosquito Vectors/genetics , Xenopus laevis , Ligands , Pyridines/pharmacology , Malaria/transmission , Malaria/parasitology , Thiazoles/pharmacology , Thiazoles/chemistry , Thiazoles/metabolism , Thiazines/pharmacology , Thiazines/chemistry , Oocytes/metabolism , Oocytes/drug effects , Female , Insect Proteins/metabolism , Insect Proteins/genetics , Insect Proteins/chemistry , Imidazoles/pharmacology , Imidazoles/chemistry
5.
Sci Rep ; 14(1): 15709, 2024 07 08.
Article in English | MEDLINE | ID: mdl-38977768

ABSTRACT

Honey bees are commonly co-exposed to pesticides during crop pollination, including the fungicide captan and neonicotinoid insecticide thiamethoxam. We assessed the impact of exposure to these two pesticides individually and in combination, at a range of field-realistic doses. In laboratory assays, mortality of larvae treated with captan was 80-90% greater than controls, dose-independent, and similar to mortality from the lowest dose of thiamethoxam. There was evidence of synergism (i.e., a non-additive response) from captan-thiamethoxam co-exposure at the highest dose of thiamethoxam, but not at lower doses. In the field, we exposed whole colonies to the lowest doses used in the laboratory. Exposure to captan and thiamethoxam individually and in combination resulted in minimal impacts on population growth or colony mortality, and there was no evidence of synergism or antagonism. These results suggest captan and thiamethoxam are each acutely toxic to immature honey bees, but whole colonies can potentially compensate for detrimental effects, at least at the low doses used in our field trial, or that methodological differences of the field experiment impacted results (e.g., dilution of treatments with natural pollen). If compensation occurred, further work is needed to assess how it occurred, potentially via increased queen egg laying, and whether short-term compensation leads to long-term costs. Further work is also needed for other crop pollinators that lack the social detoxification capabilities of honey bee colonies and may be less resilient to pesticides.


Subject(s)
Captan , Drug Synergism , Fungicides, Industrial , Insecticides , Thiamethoxam , Animals , Thiamethoxam/toxicity , Bees/drug effects , Bees/physiology , Insecticides/toxicity , Fungicides, Industrial/toxicity , Captan/toxicity , Larva/drug effects , Neonicotinoids/toxicity , Thiazoles/toxicity , Nitro Compounds/toxicity
6.
Environ Sci Pollut Res Int ; 31(33): 45954-45969, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38980489

ABSTRACT

Uncontrolled use of pesticides has caused a dramatic reduction in the number of pollinators, including bees. Studies on the effects of pesticides on bees have reported effects on both metabolic and neurological levels under chronic exposure. In this study, variations in the differential expression of head and thorax-abdomen proteins in Africanized A. mellifera bees treated acutely with sublethal doses of glyphosate and imidacloprid were studied using a proteomic approach. A total of 92 proteins were detected, 49 of which were differentially expressed compared to those in the control group (47 downregulated and 2 upregulated). Protein interaction networks with differential protein expression ratios suggested that acute exposure of A. mellifera to sublethal doses of glyphosate could cause head damage, which is mainly associated with behavior and metabolism. Simultaneously, imidacloprid can cause damage associated with metabolism as well as, neuronal damage, cellular stress, and impairment of the detoxification system. Regarding the thorax-abdomen fractions, glyphosate could lead to cytoskeleton reorganization and a reduction in defense mechanisms, whereas imidacloprid could affect the coordination and impairment of the oxidative stress response.


Subject(s)
Glycine , Glyphosate , Neonicotinoids , Nitro Compounds , Proteome , Animals , Bees/drug effects , Neonicotinoids/toxicity , Glycine/analogs & derivatives , Glycine/toxicity , Nitro Compounds/toxicity , Imidazoles/toxicity , Insecticides/toxicity
7.
Redox Biol ; 74: 103202, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38865901

ABSTRACT

Stimulator of Interferon Genes (STING) is essential for the inflammatory response to cytosolic DNA. Despite that aberrant activation of STING is linked to an increasing number of inflammatory diseases, the development of inhibitors has been challenging, with no compounds in the pipeline beyond the preclinical stage. We previously identified endogenous nitrated fatty acids as novel reversible STING inhibitors. With the aim of improving the specificity and efficacy of these compounds, we developed and tested a library of nitroalkene-based compounds for in vitro and in vivo STING inhibition. The structure-activity relationship study revealed a robustly improved electrophilicity and reduced degrees of freedom of nitroalkenes by conjugation with an aromatic moiety. The lead compounds CP-36 and CP-45, featuring a ß-nitrostyrene moiety, potently inhibited STING activity in vitro and relieved STING-dependent inflammation in vivo. This validates the potential for nitroalkene compounds as drug candidates for STING modulation to treat STING-driven inflammatory diseases, providing new robust leads for preclinical development.


Subject(s)
Alkenes , Inflammation , Membrane Proteins , Nitro Compounds , Membrane Proteins/antagonists & inhibitors , Membrane Proteins/metabolism , Animals , Inflammation/drug therapy , Humans , Mice , Alkenes/chemistry , Alkenes/pharmacology , Nitro Compounds/chemistry , Nitro Compounds/pharmacology , Structure-Activity Relationship
8.
J Am Soc Mass Spectrom ; 35(7): 1609-1621, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38907730

ABSTRACT

2-Benzylbenzimidazoles, or "nitazenes", are a class of novel synthetic opioids (NSOs) that are increasingly being detected alongside fentanyl analogs and other opioids in drug overdose cases. Nitazenes can be 20× more potent than fentanyl but are not routinely tested for during postmortem or clinical toxicology drug screens; thus, their prevalence in drug overdose cases may be under-reported. Traditional analytical workflows utilizing liquid chromatography-tandem mass spectrometry (LC-MS/MS) often require additional confirmation with authentic reference standards to identify a novel nitazene. However, additional analytical measurements with ion mobility spectrometry (IMS) may provide a path toward reference-free identification, which would greatly accelerate NSO identification rates in toxicology laboratories. Presented here are the first IMS and collision cross section (CCS) measurements on a set of fourteen nitazene analogs using a structures for lossless ion manipulations (SLIM)-orbitrap MS. All nitazenes exhibited two high intensity baseline-separated IMS distributions, which fentanyls and other drug and druglike compounds also exhibit. Incorporating water into the electrospray ionization (ESI) solution caused the intensities of the higher mobility IMS distributions to increase and the intensities of the lower mobility IMS distributions to decrease. Nitazenes lacking a nitro group at the R1 position exhibited the greatest shifts in signal intensities due to water. Furthermore, IMS-MS/MS experiments showed that the higher mobility IMS distributions of all nitazenes possessing a triethylamine group produced fragment ions with m/z 72, 100, and other low intensity fragments while the lower mobility IMS distributions only produced fragment ions with m/z 72 and 100. The IMS, solvent, and fragmentation studies provide experimental evidence that nitazenes potentially exhibit three gas-phase protomers. The cyclic IMS capability of SLIM was also employed to partially resolve four sets of structurally similar nitazene isomers (e.g., protonitazene/isotonitazene, butonitazene/isobutonitazene/secbutonitazene), showcasing the potential of using high-resolution IMS separations in MS-based workflows for reference-free identification of emerging nitazenes and other NSOs.


Subject(s)
Ion Mobility Spectrometry , Ion Mobility Spectrometry/methods , Analgesics, Opioid/chemistry , Analgesics, Opioid/analysis , Tandem Mass Spectrometry/methods , Spectrometry, Mass, Electrospray Ionization/methods , Benzimidazoles/chemistry , Benzimidazoles/analysis , Gases/chemistry , Nitro Compounds/chemistry , Nitro Compounds/analysis , Ions/chemistry
9.
Pestic Biochem Physiol ; 202: 105958, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38879340

ABSTRACT

The wheat aphid Sitobion miscanthi is a dominant and destructive pest in agricultural production. Insecticides are the main substances used for effective control of wheat aphids. However, their extensive application has caused severe resistance of wheat aphids to some insecticides; therefore, exploring resistance mechanisms is essential for wheat aphid management. In the present study, CYP6CY2, a new P450 gene, was isolated and overexpressed in the imidacloprid-resistant strain (SM-R) compared to the imidacloprid-susceptible strain (SM-S). The increased sensitivity of S. miscanthi to imidacloprid after knockdown of CYP6CY2 indicates that it could be associated with imidacloprid resistance. Subsequently, the posttranscriptional regulation of CYP6CY2 in the 3' UTR by miR-3037 was confirmed, and CYP6CY2 participated in imidacloprid resistance. This finding is critical for determining the role of P450 in relation to the resistance of S. miscanthi to imidacloprid. It is of great significance to understand this regulatory mechanism of P450 expression in the resistance of S. miscanthi to neonicotinoids.


Subject(s)
Aphids , Cytochrome P-450 Enzyme System , Insecticide Resistance , Insecticides , MicroRNAs , Neonicotinoids , Nitro Compounds , Neonicotinoids/pharmacology , Nitro Compounds/pharmacology , Animals , Insecticides/pharmacology , Insecticide Resistance/genetics , Aphids/genetics , Aphids/drug effects , MicroRNAs/genetics , MicroRNAs/metabolism , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Insect Proteins/genetics , Insect Proteins/metabolism , Imidazoles/pharmacology
10.
Pestic Biochem Physiol ; 202: 105973, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38879316

ABSTRACT

Using a high-efficiency insecticide in combination with fungicides that have different mechanisms of action is a conventional method in the current management of brown planthopper (BPH) resistance. In this study, we investigate the separate and combined effects of the low-toxicity fungicide validamycin and the non-cross-resistant insecticide imidacloprid on the fitness and symbiosis of BPH. These research results indicate that when the proportion of active ingredients in validamycin is combined with imidacloprid at a ratio of 1:30, the toxicity ratio and co-toxicity coefficient are 1.34 and 691.73, respectively, suggesting that the combination has a synergistic effect on the control of BPH. The number of yeast-like symbiotic (YLS) and dominant symbiotic (Noda) in the imidacloprid + validamycin groups were significantly lower than the other three treatment groups (validamycin, imidacloprid, and water). The results of the study on population fitness show that the lifespan of the BPH population in validamycin, imidacloprid, and imidacloprid + validamycin was shortened. Notably, the BPH populations in the imidacloprid + validamycin groups were significantly lower than other groups in terms of average generation cycle, intrinsic growth rate, net reproduction rate, finite rate of increase, and fitness. The Real-time quantitative PCR showed that validamycin and imidacloprid + validamycin can significantly inhibit the expression of the farnesyl diphosphate farnesyl transferase gene (EC2.5.1.21) and uricase gene (EC1.7.3.3), with imidacloprid + validamycin demonstrating the most pronounced inhibitory effect. Our research results can provide insights and approaches for delaying resistance and integrated management of BPH.


Subject(s)
Hemiptera , Insecticides , Neonicotinoids , Nitro Compounds , Symbiosis , Animals , Hemiptera/drug effects , Neonicotinoids/pharmacology , Nitro Compounds/pharmacology , Insecticides/pharmacology , Inositol/analogs & derivatives , Inositol/pharmacology , Imidazoles/pharmacology , Fungicides, Industrial/pharmacology
11.
Pestic Biochem Physiol ; 202: 105939, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38879330

ABSTRACT

The brown planthopper (BPH), Nilaparvata lugens is a devastating agricultural pest of rice, and they have developed resistance to many pesticides. In this study, we assessed the response of BPH nymphs to nitenpyram, imidacloprid, and etofenprox using contact and dietary bioassays, and investigated the underlying functional diversities of BPH glutathione-S-transferase (GST), carboxylesterase (CarE) and cytochrome P450 monooxygenase (P450) against these insecticides. Both contact and ingestion toxicity of nitenpyram to BPH were significantly higher than either imidacloprid or etofenprox. Under the LC50 concentration of each insecticide, they triggered a distinct response for GST, CarE, and P450 activities, and each insecticide induced at least one detoxification enzyme activity. These insecticides almost inhibited the expression of all tested GST, CarE, and P450 genes in contact bioassays but induced the transcriptional levels of these genes in dietary bioassays. Silencing of NlGSTD2 expression had the greatest effect on BPH sensitivity to nitenpyram in contact test and imidacloprid in dietary test. The sensitivities of BPH to insecticide increased the most in the contact test was etofenprox after silencing of NlCE, while the dietary test was nitenpyram. Knockdown of NlCYP408A1 resulted in BPH sensitivities to insecticide increasing the most in the contact test was nitenpyram, while the dietary test was imidacloprid. Taken together, these findings reveal that NlGSTD2, NlCE, and NlCYP408A1 play an indispensable role in the detoxification of the contact and ingestion toxicities of different types of insecticides to BPH, which is of great significance for the development of new strategies for the sucking pest control.


Subject(s)
Carboxylesterase , Cytochrome P-450 Enzyme System , Glutathione Transferase , Hemiptera , Insecticides , Neonicotinoids , Nitro Compounds , Pyrethrins , RNA Interference , Animals , Hemiptera/drug effects , Hemiptera/genetics , Insecticides/toxicity , Insecticides/pharmacology , Neonicotinoids/toxicity , Neonicotinoids/pharmacology , Nitro Compounds/toxicity , Glutathione Transferase/metabolism , Glutathione Transferase/genetics , Carboxylesterase/genetics , Carboxylesterase/metabolism , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Pyrethrins/toxicity , Pyrethrins/pharmacology , Inactivation, Metabolic , Nymph/drug effects , Nymph/genetics , Insect Proteins/genetics , Insect Proteins/metabolism , Insecticide Resistance/genetics , Pyridines/toxicity , Pyridines/pharmacology
12.
Pestic Biochem Physiol ; 202: 105935, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38879327

ABSTRACT

Imidacloprid (IMI) is a contaminant widespread in surface water, causing serious intestinal damage in the common carp. Melatonin (MT), an endogenous indoleamine hormone, plays a crucial role in mitigating pesticide-induced toxicity. Our previous research has demonstrated that MT effectively reduces the production of intestinal microbial-derived signal peptidoglycan (PGN) induced by IMI, thereby alleviating intestinal tight junction injuries in the common carp. In this study, we performed a transcriptomic analysis to explore the effect of MT on the IMI exposure-induced gut damage of the common carp. The results elucidated that the ferroptosis, mitogen-activated protein kinases (MAPKs), and nucleotide oligomerization domain (NOD)-like signaling pathways were significantly associated with IMI exposure and MT treatment. Meanwhile, the exposure to IMI resulted in the formation of pyroptotic bodies and distinct morphological features of ferroptosis, both mitigated with the addition of MT. Immunofluorescence double staining demonstrated that MT abolished the elevated expression of NOD-like receptor thermal protein domain associated protein 3 (NLRP3) and Gasdermin D (GSDMD) induced by IMI, as well as reduced expression of ferritin heavy chains (FTH) and glutathione peroxidase 4 (GPX4) in gut tissues. Subsequently, we found that the exposure to IMI or PGN enhanced the expression of toll-like receptors (TLR) 2 (a direct recognition receptor of PGN) triggering the P38MAPK signaling pathway, thereby aggravating the process of pyroptosis and ferroptosis of cell models. The addition of MT or SB203580 (a P38MAPK inhibitor) significantly reduced pyroptotic cells, and also decreased iron accumulation. Consequently, these results indicate that MT alleviates IMI-induced pyroptosis and ferroptosis in the gut of the common carp through the PGN/TLR2/P38MAPK pathway.


Subject(s)
Carps , Ferroptosis , Melatonin , Neonicotinoids , Nitro Compounds , Peptidoglycan , Pyroptosis , Animals , Carps/metabolism , Ferroptosis/drug effects , Melatonin/pharmacology , Pyroptosis/drug effects , Neonicotinoids/pharmacology , Neonicotinoids/toxicity , Peptidoglycan/pharmacology , Nitro Compounds/toxicity , Nitro Compounds/pharmacology , Insecticides/toxicity , Intestines/drug effects
13.
Sci Total Environ ; 942: 173685, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-38825192

ABSTRACT

Pesticide mixtures are frequently utilized in agriculture, yet their cumulative effects on aquatic organisms remain poorly understood. Aquatic animals can be effective bioindicators and invasive bivalves, owing to their widespread distribution, provide an opportunity to assess these impacts. Glyphosate and imidacloprid, among the most prevalent pesticides globally, are frequently detected in freshwater systems in South America. This study aims to understand the cumulative effects of pesticide mixtures on aquatic organisms, using invasive Corbicula largillierti clams from a natural stream in northwestern Argentina. We conducted 48-hour exposure experiments using two concentrations of imidacloprid (20 and 200 µg L-1 a.i), two concentrations of glyphosate (0.3 and 3 mg L-1 a.i), and two combinations of these pesticides (both at low and high concentrations, respectively), simulating the direct contamination of both pesticides based on their agronomic recipe and observed values in Argentine aquatic environments. Clam metabolism was assessed through the examination of multiple oxidative stress parameters and measuring oxygen consumption rate as a proxy for standard metabolic rate (SMR). Our findings revealed that imidacloprid has a more pronounced effect compared to glyphosate. Imidacloprid significantly decreased clam SMR and cellular levels of reduced glutathione (GSH). However, when both pesticides were present, also cellular glycogen and thiobarbituric acid-reactive substances (TBARS) were affected. Proteins and glutathione S-Transferase (GST) activity were unaffected by either pesticide or their mixture at the assayed concentrations, highlighting the need to test several stress parameters to detect toxicological impacts. Our results indicated additive effects of imidacloprid and glyphosate across all measured parameters. The combination of multiple physiological and cytological biomarkers in invasive bivalves offers significant potential to enhance biomonitoring sensitivity and obtain insights into the origins and cellular mechanisms of chemical impacts. These studies can improve pollution regulatory policies and pesticide management.


Subject(s)
Biomarkers , Corbicula , Glycine , Glyphosate , Neonicotinoids , Nitro Compounds , Water Pollutants, Chemical , Neonicotinoids/toxicity , Animals , Nitro Compounds/toxicity , Water Pollutants, Chemical/toxicity , Glycine/analogs & derivatives , Glycine/toxicity , Biomarkers/metabolism , Argentina , Corbicula/drug effects , Herbicides/toxicity , Environmental Monitoring , Oxidative Stress/drug effects , Insecticides/toxicity
14.
Chemosphere ; 361: 142511, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38825249

ABSTRACT

Environmental ambient temperature significantly impacts the metabolic activities of aquatic ectotherm organisms and influences the fate of various chemicals. Although numerous studies have shown that the acute lethal toxicity of most chemicals increases with increasing temperature, the impact of temperature on chronic effects - encompassing both lethal and sublethal endpoints - has received limited attention. Furthermore, the mechanisms linking temperature and toxicity, potentially unveiled by toxicokinetic-toxicodynamic models (TKTD), remains inadequately explored. This study investigated the effects of environmentally relevant concentrations of the insecticide imidacloprid (IMI) on the growth and survival of the freshwater amphipod Gammarus pulex at two different temperatures. Our experimental design was tailored to fit a TKTD model, specifically the Dynamic Energy Budget (DEB) model. We conducted experiments spanning three and six months, utilizing small G. pulex juveniles. We observed effects endpoints at least five times, employing both destructive and non-destructive methods, crucial for accurate model fittings. Our findings reveal that IMI at environmental concentrations (up to 0.3 µg/L) affects the growth and survival of G. pulex, albeit with limited effects, showing a 10% inhibition compared to the control group. These limited effects, observed in both lethal and sublethal aspects, suggest a different mode of action at low, environmentally-relevant concentrations in long-term exposure (3 months), in contrast to previous studies which applied higher concentrations and found that sublethal effects occurred at significantly lower levels than lethal effects in an acute test setting (4 days). Moreover, after parameterizing the DEB model for various temperatures, we identified a lower threshold for both lethal and sublethal effects at higher temperatures, indicating increased intrinsic sensitivity. Overall, this study contributes to future risk assessments considering temperature as a crucial factor and exemplifies the integration of the DEB model into experimental design for comprehensive toxicity evaluations.


Subject(s)
Amphipoda , Insecticides , Neonicotinoids , Nitro Compounds , Temperature , Water Pollutants, Chemical , Neonicotinoids/toxicity , Animals , Nitro Compounds/toxicity , Amphipoda/drug effects , Water Pollutants, Chemical/toxicity , Insecticides/toxicity , Toxicokinetics , Imidazoles/toxicity
15.
Eur J Med Chem ; 274: 116559, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38850856

ABSTRACT

Tuberculosis remains the second deadliest infectious disease in humans and a public health threat due to the emergence of multidrug-resistant (MDR-TB) and extensively drug-resistant (XDR-TB) strains. Therefore, it is urgent to identify new anti-tuberculosis treatments and novel therapeutic targets to prevent the emergence of resistance. In recent years, the study of anti-tuberculosis properties of nitroaromatic compounds has led to the identification of two novel biological targets, the deazaflavin (F420)-dependent nitroreductase Ddn and the decaprenylphosphoryl-ß-d-ribose 2'-epimerase DprE1. This review aims to show why Ddn and DprE1 are promising therapeutic targets and highlight nitroaromatic compounds interest in developing new anti-tuberculosis treatments active against MDR-TB and XDR-TB. Despite renewed interest in the development of new anti-tuberculosis nitroaromatic compounds, pharmaceutical companies often exclude nitro-containing molecules from their drug discovery programs because of their toxic and mutagenic potential. This exclusion results in missed opportunities to identify new nitroaromatic compounds and promising therapeutic targets.


Subject(s)
Antitubercular Agents , Mycobacterium tuberculosis , Nitroreductases , Antitubercular Agents/pharmacology , Antitubercular Agents/chemistry , Humans , Mycobacterium tuberculosis/drug effects , Nitroreductases/metabolism , Bacterial Proteins/antagonists & inhibitors , Bacterial Proteins/metabolism , Nitro Compounds/chemistry , Nitro Compounds/pharmacology , Molecular Structure , Microbial Sensitivity Tests , Drug Development , Alcohol Oxidoreductases
16.
Sci Total Environ ; 944: 173845, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-38871314

ABSTRACT

Terrestrial ectotherms are vulnerable to climate change since their biological rates depend on the ambient temperature. As temperature may interact with toxicant exposure, climate change may cause unpredictable responses to toxic stress. A population's thermal adaptation will impact its response to temperature change, but also to interactive effects from temperature and toxicants, but these effects are still not fully understood. Here, we assessed the combined effects of exposure to the insecticide imidacloprid across the temperatures 10-25 °C of two populations of the Collembola Hypogastrura viatica (Tullberg, 1872), by determining their responses in multiple life history traits. The con-specific populations differ considerably in thermal adaptations; one (arctic) is a temperature generalist, while the other (temperate) is a warm-adapted specialist. For both populations, the sub-lethal concentrations of imidacloprid became lethal with increasing temperature. Although the thermal maximum is higher for the warm-adapted population, the reduction in survival was stronger. Growth was reduced by imidacloprid in a temperature-dependent manner, but only at the adult life stage. The decrease in adult body size combined with the absence of an effect on the age at first reproduction suggests a selection on the timing of maturation. Egg production was reduced by imidacloprid in both populations, but the negative effect was only dependent on temperature in the warm-adapted population, with no effect at 10 °C, and decreases of 41 % at 15 °C, and 74 % at 20 °C. For several key traits, the population best adapted to utilize high temperatures was also the most sensitive to toxic stress at higher temperatures. It could be that by allocating more energy to faster growth, development, and reproduction at higher temperatures, the population had less energy for maintenance, making it more sensitive to toxic stress. Our findings demonstrate the need to take into account a population's thermal adaptation when assessing the interactive effects between temperature and other stressors.


Subject(s)
Climate Change , Insecticides , Neonicotinoids , Nitro Compounds , Temperature , Neonicotinoids/toxicity , Nitro Compounds/toxicity , Animals , Insecticides/toxicity , Arthropods/drug effects , Arthropods/physiology , Soil Pollutants/toxicity , Soil/chemistry , Adaptation, Physiological , Imidazoles/toxicity
17.
Sci Total Environ ; 944: 174014, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-38880156

ABSTRACT

The threat of neonicotinoids to insect pollinators, particularly honeybees (Apis mellifera), is a global concern, but the risk of chiral neonicotinoids to insect larvae remains poorly understood. In the current study, we evaluated the acute and chronic toxicity of dinotefuran enantiomers to honeybee larvae in vitro and explored the mechanism of toxicity. The results showed that the acute median lethal dose (LD50) of S-dinotefuran to honeybee larvae was 30.0 µg/larva after oral exposure for 72 h, which was more toxic than rac-dinotefuran (92.7 µg/larva) and R-dinotefuran (183.6 µg/larva). Although the acute toxicity of the three forms of dinotefuran to larvae was lower than that to adults, chronic exposure significantly reduced larval survival, larval weight, and weight of newly emerged adults. Analysis of gene expression and hormone titer indicated that dinotefuran affects larval growth and development by interfering with nutrient digestion and absorption and the molting system. Analysis of hemolymph metabolome further revealed that disturbances in the neuroactive ligand-receptor interaction pathway and energy metabolism are the key mechanisms of dinotefuran toxicity to bee larvae. In addition, melatonin and vitellogenin are used by larvae to cope with dinotefuran-induced oxidative stress. Our results contribute to a comprehensive understanding of dinotefuran damage to bees and provide new insights into the mechanism of enantioselective toxicity of insecticides to insect larvae.


Subject(s)
Guanidines , Insecticides , Larva , Neonicotinoids , Nitro Compounds , Animals , Bees/drug effects , Neonicotinoids/toxicity , Larva/drug effects , Guanidines/toxicity , Nitro Compounds/toxicity , Insecticides/toxicity , Stereoisomerism , Lethal Dose 50
18.
Nat Commun ; 15(1): 4813, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38844461

ABSTRACT

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) poses a major threat to the global swine industry, yet effective prevention and control measures remain elusive. This study unveils Nitazoxanide (NTZ) as a potent inhibitor of PRRSV both in vitro and in vivo. Through High-Throughput Screening techniques, 16 potential anti-PRRSV compounds are identified from a library comprising FDA-approved and pharmacopeial drugs. We show that NTZ displays strong efficacy in reducing PRRSV proliferation and transmission in a swine model, alleviating viremia and lung damage. Additionally, Tizoxanide (TIZ), the primary metabolite of NTZ, has been identified as a facilitator of NMRAL1 dimerization. This finding potentially sheds light on the underlying mechanism contributing to TIZ's role in augmenting the sensitivity of the IFN-ß pathway. These results indicate the promising potential of NTZ as a repurposed therapeutic agent for Porcine Reproductive and Respiratory Syndrome (PRRS). Additionally, they provide valuable insights into the antiviral mechanisms underlying NTZ's effectiveness.


Subject(s)
Antiviral Agents , High-Throughput Screening Assays , Nitro Compounds , Porcine Reproductive and Respiratory Syndrome , Porcine respiratory and reproductive syndrome virus , Thiazoles , Animals , Porcine respiratory and reproductive syndrome virus/drug effects , Nitro Compounds/pharmacology , Swine , Antiviral Agents/pharmacology , High-Throughput Screening Assays/methods , Porcine Reproductive and Respiratory Syndrome/drug therapy , Porcine Reproductive and Respiratory Syndrome/virology , Thiazoles/pharmacology , Virus Replication/drug effects , Cell Line , Viremia/drug therapy , Viremia/virology
19.
Vet Med Sci ; 10(4): e1500, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38864312

ABSTRACT

BACKGROUND: Sarcoptic mange is rare in cats. The main symptoms reported in cases of feline sarcoptic mange include crusty lesions and pruritus, although these may vary in severity among individuals. OBJECTIVES: This report describes three cats infested with Sarcoptes scabiei, all presenting with pruritus and excoriation. METHODS: The diagnosis was confirmed by microscopic observation of skin scrape samples. RESULTS: All three cats were treated successfully using moxidectin and imidacloprid, selamectin and ivermectin, respectively. CONCLUSIONS: The clinical presentation of feline scabies appears to be more variable in cats than in dogs. Infestation with S. scabiei should be considered a differential diagnosis for cats presenting with pruritic inflammatory skin disease.


Subject(s)
Cat Diseases , Sarcoptes scabiei , Scabies , Animals , Scabies/veterinary , Scabies/drug therapy , Scabies/diagnosis , Cat Diseases/parasitology , Cat Diseases/drug therapy , Cat Diseases/diagnosis , Cats , Male , Female , Poland , Sarcoptes scabiei/drug effects , Ivermectin/therapeutic use , Ivermectin/analogs & derivatives , Nitro Compounds/therapeutic use , Neonicotinoids/therapeutic use , Insecticides/therapeutic use , Macrolides
20.
PLoS One ; 19(6): e0290858, 2024.
Article in English | MEDLINE | ID: mdl-38833488

ABSTRACT

The tarnished plant bug, (TPB) Lygus lineolaris Palisot de Beauvois (Hemiptera: Miridae) is a key pest of cotton in the midsouth region and some areas of the eastern United States. Its control methods have been solely based on chemical insecticides which has contributed to insecticidal resistance and shortened residual periods for control of this insect pest. This study was conducted over a two-year period and examined the efficacy and residual effect of four commercial insecticides including lambda-cyhalothrin (pyrethroid), acephate (organophosphate), imidacloprid (neonicotinoid), and sulfoxaflor (sulfoxamine). The effectiveness and residual effects of these insecticides were determined by application on cotton field plots on four different dates during each season using three different concentrations (high: highest labeled commercial dose (CD), medium: 1/10 of the CD, low: 1/100 of the CD) on field cotton plots. Four groups of cotton leaves were randomly pulled from each treated plot and control 0-, 2-, 4-, 7-, and 9-days post treatment (DPT) and exposed to a lab colony of TPB adults. One extra leaf sample/ plot/ spray /DPT interval (0-2-4-7-9-11) during 2016 was randomly collected from the high concentration plots and sent to Mississippi State Chemical Laboratory for residual analysis. Mortality of TPB adults was greatest for those placed on leaves sprayed with the organophosphate insecticide with mortalities (%) of 81.7±23.4 and 63.3±28.8 (SE) 1-day after exposure (DAE) on leaves 0-DPT with the high concentration for 2016 and 2017, respectively, reaching 94.5±9.5 and 95.4±7.6 6-DAE each year. Mortality to all insecticides continued until 9 and 4-DPT for high and medium concentrations, respectively. However, organophosphate (39.4±28.6) and pyrethroid (24.4±9.9) exhibited higher mortality than sulfoxamine (10.6±6.6) and the neonicotinoid (4.0±1.5) 7-DAE on 9-DPT leaves with the high concentration. Based on our results using the current assay procedure, TPB adults were significantly more susceptible to contact than systemic insecticides and due to its residual effect, organophosphate could kill over 80% of the TPB population 7-DPT.


Subject(s)
Gossypium , Insecticides , Neonicotinoids , Nitriles , Nitro Compounds , Phosphoramides , Pyrethrins , Insecticides/pharmacology , Gossypium/parasitology , Animals , Pyrethrins/pharmacology , Neonicotinoids/pharmacology , Mississippi , Nitriles/pharmacology , Nitro Compounds/pharmacology , Insect Control/methods , Heteroptera/drug effects , Imidazoles/pharmacology , Hemiptera/drug effects , Organothiophosphorus Compounds , Pyridines , Sulfur Compounds
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