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Paraquat (PQ) poisoning leads to irreversible fibrosis in the lungs with high mortality and no known antidote. In this study, we investigated the effect of the SET and MYND domain containing 2 (SMYD2) on PQ-induced pulmonary fibrosis (PF) and its potential mechanisms. We established an in vivo PQ-induced PF mouse model by intraperitoneal injection of PQ (20 mg/kg) and in vitro PQ (25 μM)-injured MLE-12 cell model. On the 15th day of administration, tissue injury, inflammation, and fibrosis in mice were evaluated using various methods including routine blood counts, blood biochemistry, blood gas analysis, western blotting, H&E staining, ELISA, Masson staining, and immunofluorescence. The findings indicated that AZ505 administration mitigated tissue damage, inflammation, and collagen deposition in PQ-poisoned mice. Mechanistically, both in vivo and in vitro experiments revealed that AZ505 treatment suppressed the PQ-induced epithelial-mesenchymal transition (EMT) process by downregulating GLI pathogenesis related 2 (GLIPR2) and ERK/p38 pathway. Further investigations demonstrated that SMYD2 inhibition decreased GLIPR2 methylation and facilitated GLIPR2 ubiquitination, leading to GLIPR2 destabilization in PQ-exposed MLE-12 cells. Moreover, rescue experiments conducted in vitro demonstrated that GLIPR2 overexpression eliminated the inhibitory effect of AZ505 on the ERK/p38 pathway and EMT. Our results reveal that the SMYD2 inhibitor AZ505 may act as a novel therapeutic candidate to suppress the EMT process by modulating the GLIPR2/ERK/p38 axis in PQ-induced PF. [Display omitted] • SMYD2 inhibition ameliorates pulmonary fibrosis in mice after PQ intoxication. • SMYD2 inhibition reverses EMT process in vivo and in vitro. • GLIPR2 is a novel non-histone target of SMYD2. • SMYD2 inhibition alleviates pulmonary fibrosis by inhibiting GLIPR2/ERK/p38 pathway. [ABSTRACT FROM AUTHOR]

Despite increasing knowledge of allelochemicals as leads for new herbicides, relatively little is known about the mode of action of allelochemical-based herbicides on herbicide-resistant weeds. In this study, herbicidal activities of a series of allelochemical tricin-derived compounds were evaluated. Subsequently, a benzothiazine derivative 3-(2-chloro-4-methanesulfonyl)-benzoyl-hydroxy-2-methyl-2H-1,2-benzothiazine-1,1-dioxide with 4-hydroxyphenyl-pyruvate dioxygenase (HPPD) inhibiting activity was identified as a target compound on photosynthetic performance of penoxsulam-resistant versus -susceptible barnyardgrass ( Echinochloa crus-galli ). Regardless of barnyardgrass biotype, the benzothiazine derivative greatly affected chlorophyll fluorescence parameters (Fv/Fm, ETR 1 min and NPQ 1 min ), reduced the chloroplast fluorescence levels and expression of HPPD gene. In particular, the benzothiazine derivative interfered with photosynthetic performance of resistant barnyardgrass more effectively than the allelochemical tricin itself. These results showed that the benzothiazine derivative effectively inhibited the growth of resistant barnyardgrass and its mode of action on photosynthesis system was similar to HPPD-inhibiting sulcotrione, making it an ideal lead compound for further development of allelochemical-based herbicide discovery. [ABSTRACT FROM AUTHOR]

Carboxylesterases (CarEs) are responsible for metabolism of xenobiotics including insecticides in insects. Understanding the expression patterns of a such detoxifying gene and effect of insecticides on its enzyme activity are important to clarify the function of this gene relevant to insecticides-detoxifying process, but little information is available in the codling moth Cydia pomonella (L.). In this study, we investigated the expression profiles of CarE gene CpCE-1 at different developmental stages and in different tissues of C. pomonella , as well as the larvae exposed to chlorpyrifos-ethyl and lambda-cyhalothrin by using absolute real-time quantitative PCR (absolute RT-qPCR). Results indicated that CpCE-1 expression was significantly altered during C. pomonella development stages, and this expression differed between sexes, with a higher transcript in females than males. Meanwhile, CpCE-1 is overexpressed in cuticle, midgut and head than silk gland, fat body and Malpighian tubules. Exposure of third instar larvae to a non-lethal dosage of chlorpyrifos-ethyl and lambda-cyhalothrin resulted in induction of CpCE-1 transcript. The total carboxylesterase enzyme activity was inhibited by chlorpyrifos-ethyl in vivo ; in contrast, the activity of Escherichia coli produced recombinant CpCE-1 was significantly inhibited by both lambda-cyhalothrin and chlorpyrifos-ethyl in vitro . These results suggested that CpCE-1 in C. pomonella is potentially involved in the development and in detoxification of chlorpyrifos-ethyl and lambda-cyhalothrin. [ABSTRACT FROM AUTHOR]

Abstract Lambda-cyhalothrin has long been recommended as an effective insecticide to control the oriental armyworm, Mythimna separata (Walker), a notorious migratory pest of agricultural plants. Previous researches have suggested that survival, development, and reproduction of insects are influenced by sublethal concentrations of insecticides. However, the effects of sublethal concentrations of lambda-cyhalothrin on M. separata are less known. In this study, we determined the toxicity and effects of LC 20 and LC 50 concentration of lambda-cyhalothrin on development and reproduction of M. separata. Results indicate that LC 20 of lambda-cyhalothrin tends to decrease the life traits of M. separate , with a shortening larvae period of offspring and oviposition period, whereas LC 50 of lambda-cyhalothrin stimulates daily maximal fecundity and forwards the oviposition peak, suggesting a stimulation of reproduction by LC 50 of lambda-cyhalothrin. The M. separata population was increased by an LC 50 concentration of lambda-cyhalothrin, resulting in a net reproductive rate (R 0) and intrinsic rate of increase (r m) significantly higher than that of the control. Transcripts of vitellogenin (MsVg) and vitellogenin receptor (MsVgR) genes were suppressed at day 1 after emergence of moth which developed from the larvae exposed to LC 20 and LC 50 of lambda-cyhalothrin, but were significant induced when the moth begin to lay eggs (day 4), with a more remarkable induction by LC 50 of lambda-cyhalothrin than those of LC 20 of lambda-cyhalothrin. Our results indicate that the observed stimulation of reproduction is therefore the results of up-regulation of MsVg and MsVgR by LC 50 of lambda-cyhalothrin. Graphical abstract Unlabelled Image Highlights • The toxicity of lambda-cyhalothrin on Mythimna separata was determined. • LC 20 of lambda-cyhalothrin decreases the life traits of M. separate. • LC 50 of lambda-cyhalothrin stimulates reproduction on moth M. separata. • LC 50 of lambda-cyhalothrin up-regulates the expression of vitellogenin and vitellogenin receptor gene in M. separata. [ABSTRACT FROM AUTHOR]

The codling moth, Cydia pomonella (Lepidoptera: Tortricidae) is a major pest of pome fruit and walnuts worldwide. Although environmentally compatible integrated control strategies, such as mating disruption, attract-kill strategy, and sterile insect technique have been conducted for management of this notorious pest, effects to control of codling moth have mainly relied on insecticides. In consequence, different levels of insecticide resistance towards organophosphates, neonicotinoids, hydrazines, benzoylureas, pyrethroids, diamides, spinosyns, avermectins, JH mimics, carbamates, oxadiazines and C. pomonella granulovirus (CpGVs) have developed in codling moth in different countries and areas. Both metabolic and target-site mechanisms conferring resistance have been revealed in the codling moth. In this review, we summarize the current global status of insecticide resistance, the biochemical and molecular mechanisms involved, and the implications for resistance management. [Display omitted] • The coding moth (CM) has developed resistance to almost all classes of insecticides. • Target-site and metabolic mechanisms are involved in insecticide resistance in CM. • Resistance management strategy for preventing resistance development is proposed. • Genomic technologies open an avenue for developing management programs in CM. [ABSTRACT FROM AUTHOR]

Deoxymikanolide (DEO) was isolated from Mikania micrantha Bunge and identified as a novel antibacterial compound previously. However, the mode of antimicrobial mechanism of DEO was not clear but hypothesized to affect the morphology and physiology of Ralstonia solanacearum cells. In this study, we confirmed our hypothesis via transmission electron microscopy (TEM) observation and comprehensive physiological analyses, including electric conductivity, glycan and phosphorus metabolism, activities of antioxidant enzymes (catalase, peroxidase, and superoxide dismutase), intrabacterial reactive oxygen species (ROS), and malondialdehyde (MDA) levels. We found that glycan and phosphorus metabolism, electric conductivity, intracellular ROS and MDA levels of R. solanacearum cells were significantly increased, while the activities of three antioxidant enzymes were significantly inhibited by DEO treatment. Moreover, TEM analysis showed that DEO treatment led to an early-stage of cell shrinkage, intermediate-stages of cytoplasmic damage, and a final-stage of cell disruption. Altogether, our data presented here indicate that DEO could adversely affect the physiology and morphology of R. solanacearum cells and be treated as an alternative antibacterial treatment in the future. [Display omitted] • The observation of ultrastructure indicated that the outer layer structure of tested cell was one of the main targets of DEO attack. • MIC and MBC of DEO were 62.5 and 125 mg/l, respectively. • The electric conductivity values of tested cell by DEO-treated sharply increased from 5 to 30 min. • The glycometabolism and phosphorus metabolism of tested cell by DEO-treated were obviously accelerated. • The three antioxidant enzymes (CAT, POD, and SOD) activities of tested cell by DEO-treated were significantly inhibited. • The intrabacterial ROS and MDA levels were apparently increased. [ABSTRACT FROM AUTHOR]