Inhibition of endoplasmic reticulum stress alleviates secondary injury after traumatic brain injury

Apoptosis after traumatic brain injury has been shown to be a major factor influencing prognosis and outcome. Endoplasmic reticulum stress may be involved in mitochondrial mediated neuronal apoptosis. Therefore, endoplasmic reticulum stress has become an important mechanism of secondary injury after traumatic brain injury. In this study, a rat model of traumatic brain injury was established by lateral fluid percussion injury. Fluorescence assays were used to measure reactive oxygen species content in the cerebral cortex. Western blot assays were used to determine expression of endoplasmic reticulum stress-related proteins. Hematoxylin-eosin staining was used to detect pathological changes in the cerebral cortex. Transmission electron microscopy was used to measure ultrastructural changes in the endoplasmic reticulum and mitochondria. Our results showed activation of the endoplasmic reticulum stress-related unfolded protein response. Meanwhile, both the endoplasmic reticulum stress response and mitochondrial apoptotic pathway were activated at different stages post-traumatic brain injury. Furthermore, pretreatment with the endoplasmic reticulum stress inhibitor, salubrinal（1 mg/kg）, by intraperitoneal injection 30 minutes before injury significantly inhibited the endoplasmic reticulum stress response and reduced apoptosis. Moreover, salubrinal promoted recovery of mitochondrial function and inhibited activation of the mitochondrial apoptotic pathway post-traumatic brain injury. These results suggest that endoplasmic reticulum stress might be a key factor for secondary brain injury post-traumatic brain injury.

Effects and mechanisms of Bacillus thuringiensis crystal toxins for mosquito larvae

Bacillus thuringiensis is a Gram-positive aerobic bacterium that produces insecticidal crystalline inclusions during sporulation phases of the mother cell. The vir- ulence factor, known as parasporal crystals, is composed of Cry and Cyt toxins. Most Cry toxins display a common 3-domain topology. Cry toxins exert intoxication through toxin activation, receptor binding and pore formation in a suitable larval gut environment. The mosquitocidal toxins of Bt subsp, israelensis （Bti） were found to be highly active against mosquito larvae and are widely used for vector control. Bt subsp, jegathesan is another strain which possesses high potency against broad range of mosquito larvae. The present review summarizes characterized receptors for Cry toxins in mosquito larvae, and will also discuss the diversity and effects of 3-D mosquitocidal Cry toxin and the ongo- ing research for Cry toxin mechanisms generated from investigations of lepidopteran and dipteran larvae.

High throughput sequencing reveals Drosophila suzukiiresponses to insecticides

Global climate change and acquired resistance to insecticides are threats to world food security.Drosophila suzukii,a devastating invasive pest in many parts of the world,causes substantial economic losses to fruit production industries,forcing farmers to apply broad-spectrum insecticides frequently,This could lead to the development of insecticide resistance.We determined the Lethal Concentration 50 (median lethal concen- tration,LC50)values of zeta-cypermethrin,spinosad,and malathion insecticides against D.suzukii colonies established from Clarke and Pierce county Georgia,United States. The LC50 values were 3 fold higher in the Pierce county population for all insecticide treatments.We then used RNA sequencing to analyze the responses of Pierce and Clarke population flies surviving a LC50 treatment of the 3 insecticides.We identified a high num- ber of differentially expressed genes that are likely involved in detoxification and reduced cuticular penetration,especially in the Pierce population,with extensive overlap in differ- entially expressed genes between the 3 insecticide treatments.Finally,we predicted fewer nonsynonymous single nucleotide variants having deleterious effects on protein function among detoxification,insecticide target,and cuticular protein encoding genes in Pierce flies.Thus a combination of increased gene expression and fewer deleterious single nu- cleotide variants highlights molecular mechanisms underlying the higher LC50 values for Pierce population flies.

Anopheles gambiae strain(Ag55)cultured cells originated from Anopheles coluzzii and are phagocytic with hemocyte-like gene expression

Anopheles gambiae and Anopheles coluzzii are closely related species that are predominant vectors of malaria in Africa.Recently,A.gambiae form M was renamed A.coluzzii and we now conclude on the basis of a diagnostic PCR-restriction fragment length polymorphism assay that Ag55 cells were derived from A.coluzzii.We established an Ag55 cell transcriptome,and KEGG pathway analysis showed that Ag55 cells are enriched in phagosome pathway transcripts.The Ag55 transcriptome has an abundance of specific transcripts characteristic of mosquito hemocytes.Functional E.coli bioparticle uptake experiments visualized by fluorescence microscopy and confocal microscopy and quantified by flow cytometry establish the phagocytic competence of Ag55 cells.Results from this investigation of Ag55 cell properties will guide researchers in the use and engineering of the Ag55 cell line to better enable investigations of Plasmodium,other microbes,and insecticidal toxins.