In vitro study of deltamethrin-induced extracellular traps in hemocytes of Ruditapes philippinarum

Signaling pathways underlying extracellular trap formation induced by Vibrio alginolyticus in Strongylocentrotus intermedius

Extracellular traps (ETs), comprising a DNA-protein network, are widespread and function as an innate immune defense in many species. Notably, Strongylocentrotus intermedius solely depend on innate immunity for disease resistance. This study investigated the formation and preliminary mechanism of ETs in the coelomocytes of the S. intermedius under the stimulation of bacterium Vibrio alginolyticus. These results revealed that as the concentration of V. alginolyticus increased, the formation of ETs became more significant. Flow cytometry analysis showed that the formation process of ETs was accompanied by changes in mitochondrial indicators, suggesting that mitochondria may be involved in the formation process of V. alginolyticus-induced ETs. Transcriptome analysis indicated that the ETs production by coelomocytes of the S. intermedius was related to glycolysis and ATP synthesis. A total of 2631 differentially expressed genes (DEGs) were screened in this transcriptome. We then screened 34 immune-related DEGs from 16 signaling pathways to construct the PPI network, and defined hub proteins corresponding to genes such as ATP6, ND2, G3PDH, MAPK7 and other related genes. These genes are related to mitochondrial function, glycolytic pathways, and immune pathways. Additionally, the formation of ETs led to alterations in multiple immune regulators, such as TNF, NF-κB, MAPK, PI3K-AKT, and mTOR, implying its role in cellular immunomodulation. Quantitative real-time PCR experiment revealed that the expression changes of some DEGs identified and validated in ET-formation coelomocytes matched transcriptome analysis results. This study provided insights into S. intermedius aquaculture, elucidated marine organism immune mechanisms, and advanced invertebrate innate immunity understanding.

Microbial degradation mechanisms, degradation pathways, and genetic engineering for pyrethroids: current knowledge and future perspectives

Pyrethroids are synthetic products derived from natural pyrethroids present in flowers and are extensively used as pesticides for agriculture, animal husbandry, and household pest control. However, excessive and prolonged usage of pyrethroid insecticides can result in adverse effects on both non-target and target species. Therefore, effective technologies need to be developed to remove pyrethroid contamination and ensure environmental safety. Microbial remediation of various pesticide contaminants is highly practicable, low cost, and eco-friendly compared to physical and chemical methods. Different microbiota are screened to eliminate or degrade the contaminants. Microbial remediation technology utilizes the natural ability of microbiota to treat contaminated areas. Previous studies have mostly focused on the isolation and screening of microorganisms for pyrethroid biodegradation, as well as on the kinetics and pathways of pyrethroid biodegradation. In order to develop effective bioremediation strategies, further research based on molecular biology and bioengineering is required for a comprehensive exploration of pyrethroid-degrading microorganisms. To date, the microbial degradation of pyrethroid pesticides and the underlying mechanisms have been rarely reviewed. Therefore, this critical review encompasses the latest knowledge on synthetic pyrethroids from structural properties, bio-toxicity, and characterization of microbial degradation strains to degradation characteristics, intrinsic mechanisms, and microbial degradation pathways. The future of microbial remediation depends on combining advanced gene technology with traditional bioremediation methods to sustainably degrade pesticide contaminants. It also summarizes the factors affecting degradation efficiency and concludes with prospects, along with current challenges and limitations.

Ocean acidification aggravates the toxicity of deltamethrin in Haliotis discus hannai: Insights from immune response, histopathology and physiological responses

Ocean acidification (OA) and other environmental factors can collectively affect marine organisms. Deltamethrin (DM), a type II pyrethroid insecticide, has been widely detected in coastal and estuarine areas, while little attention has been given to the combined effects of DM and OA. In this study, Haliotis discus hannai was exposed to three pH levels (8.1, 7.7 and 7.4) and three DM nominal concentrations (0 μg/L, 0.6 μg/L and 6 μg/L) for 14 and 28 days. The results indicated that experimental acidification and/or DM exposure led to impaired immune function and pathological damage. Additionally, acidified conditions and DM exposure induced oxidative stress, and gills are more sensitive than digestive glands. With increasing pCO2 and DM nominal concentrations, superoxide dismutase (SOD) activity decreased, whereas catalase (CAT) and glutathione S-transferase (GST) activities increased in the gills. Moreover, the expression levels of Toll-like receptor (TLR) pathway-related genes were upregulated after exposure. Integrated biomarker response (IBR) analysis proved that acidified conditions and/or DM detrimentally affected the overall fitness of H. discus hannai, and co-exposure to experimental acidification and DM was the most stressful condition. This study emphasizes the necessity of incorporating OA in future pollutant environmental assessments to better elucidate the risks of environmental disturbance.

In Vivo Exposure of Deltamethrin Dysregulates the NFAT Signalling Pathway and Induces Lung Damage

Deltamethrin is an insecticide used to control harmful agricultural insects that otherwise damage crops and to control vector-borne diseases. Long-term exposure to deltamethrin results in the inflammation of the lungs. The present study elucidates the molecular mechanism underlying the deltamethrin-induced lung damage. The lung samples were extracted from the Swiss albino mice following the treatment of low (2.5 mg/kg) and high (5 mg/kg) doses of deltamethrin. The mRNA expression of TCR, IL-4, and IL-13 showed upregulation, while the expression of NFAT and FOS was downregulated following a low dose of deltamethrin. Moreover, the expression of TCR was downregulated with the exposure of a high dose of deltamethrin. Furthermore, the immunohistochemistry data confirmed the pattern of protein expression for TCR, FOS, IL-4, and IL-13 following a low dose of deltamethrin exposure. However, no change was seen in the TCR, NFAT, FOS, JUN, IL-4, and IL-13 immunopositive cells of the high-dose treatment group. Also, ELISA results showed increased expression of IL-13 in the BAL fluid of animals exposed to low doses of deltamethrin. Overall, the present study showed that deltamethrin exposure induces lung damage and immune dysregulation via dysregulating the NFAT signalling pathway.

Emodin Blocks mPTP Opening and Improves LPS-Induced HMEC-1 Cell Injury by Upregulation of ATP5A1

BACKGROUND

Emodin has been shown to exert anti-inflammatory and cytoprotective effects. Our study aimed to identify a novel anti-inflammatory mechanism of emodin.

METHODS

An LPS-induced model of microvascular endothelial cell (HMEC-1) injury was constructed. Cell proliferation was examined using a CCK-8 assay. The effects of emodin on reactive oxygen species (ROS), cell migration, the mitochondrial membrane potential (MMP), and the opening of the mitochondrial permeability transition pore (mPTP) were evaluated. Actin-Tracker Green was used to examine the relationship between cell microfilament reconstruction and ATP5A1 expression. The effects of emodin on the expression of ATP5A1, NALP3, and TNF-α were determined. After treatment with emodin, ATP5A1 and inflammatory factors (TNF-α, IL-1, IL-6, IL-13 and IL-18) were examined by Western blotting.

RESULTS

Emodin significantly increased HMEC-1 cell proliferation and migration, inhibited the production of ROS, increased the mitochondrial membrane potential, and blocked the opening of the mPTP. Moreover, emodin could increase ATP5A1 expression, ameliorate cell microfilament remodeling, and decrease the expression of inflammatory factors. In addition, when ATP5A1 was overexpressed, the regulatory effect of emodin on inflammatory factors was not significant.

CONCLUSION

Our findings suggest that emodin can protect HMEC-1 cells against inflammatory injury. This process is modulated by the expression of ATP5A1.