ABSTRACT
Glaesserella parasuis (G. parasuis) causes serious inflammation and meningitis in piglets. Quercetin has anti-inflammatory and anti-bacterial activities; however, whether quercetin can alleviate brain inflammation and provide protective effects during G. parasuis infection has not been studied. Here, we established a mouse model of G. parasuis infection in vivo and in vitro to investigate transcriptome changes in the mouse cerebrum and determine the protective effects of quercetin on brain inflammation and blood-brain barrier (BBB) integrity during G. parasuis infection. The results showed that G. parasuis induced brain inflammation, destroyed BBB integrity, and suppressed PI3K/Akt/Erk signaling-pathway activation in mice. Quercetin decreased the expression of inflammatory cytokines (Il-18, Il-6, Il-8, and Tnf-α) and BBB-permeability marker genes (Mmp9, Vegf, Ang-2, and Et-1), increased the expression of angiogenetic genes (Sema4D and PlexinB1), reduced G. parasuis-induced tight junction disruption, and reactivated G. parasuis-induced suppression of the PI3K/Akt/Erk signaling pathway in vitro. Thus, we concluded that quercetin may protect BBB integrity via the PI3K/Akt/Erk signaling pathway during G. parasuis infection. This was the first attempt to explore the protective effects of quercetin on brain inflammation and BBB integrity in a G. parasuis-infected mouse model. Our findings indicated that quercetin is a promising natural agent for the prevention and treatment of G. parasuis infection.
Subject(s)
Blood-Brain Barrier , Disease Models, Animal , MAP Kinase Signaling System , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Quercetin , Animals , Blood-Brain Barrier/drug effects , Blood-Brain Barrier/metabolism , Quercetin/pharmacology , Mice , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , MAP Kinase Signaling System/drug effects , Meningitis/microbiology , Meningitis/drug therapy , Meningitis/metabolism , Haemophilus Infections/drug therapy , Haemophilus Infections/microbiology , Signal Transduction/drug effects , Haemophilus parasuis/drug effects , Haemophilus parasuis/pathogenicity , Cytokines/metabolism , SwineABSTRACT
Scaling effects of low-dimensional relaxor ferroelectric single crystals have induced large delocalization of domain switching, leading to a dramatic increase in pyro-electric performances by 2-5.5 times, and promoting the detectivity of fabricated pyroelectric detectors to an international leading level of 2.21 × 10(9) cmHz(1/2) /W at 10 Hz, 4 times higher than that of commercial LiTaO3 -based detectors.
ABSTRACT
OBJECTIVE: To study the proteomic change in lymphocytes of rabbits with scald injury and Staphylococcus aureus (SA) invasion. METHODS: Twenty-four rabbits were divided into four groups as follows: control group, scald group, scald with SA invasion 2 hs group, and scald with SA invasion 6 hs group, according to random number table, with 6 rabbits in each group. Except for rabbits in control group (sham scald at 37 degrees C), rabbits in the other 3 groups were subjected to 30% TBSA full-thickness scald. Rabbits in SA invasion 2 and 6 hs groups were injected with 2 mL (1.0 x 10(8) CFU/mL) SA suspension, which was in the log growth phase, via auricle vein 18 hs and 22 hs after injury. Whole blood samples were collected from carotid artery of rabbits in 4 groups 24 hs after scald. Lymphocytes were isolated and its extracted proteins were analyzed by two-dimensional gel electrophoresis coupled with mass spectroscopy. RESULTS: About 1030 protein spots of lymphocytes were detected in each group. Compared with that of control group, 19 protein spots were found to be differentially expressed in the other 3 groups, and 11 spots (10 proteins) were identified. Expression levels of cofilin, cyclophilin A, ubiquitin, nucleoside diphosphate kinase, glutamate dehydrogenase and annexin 1 were down-regulated, but expression level of peroxiredoxin was up-regulated obviously. CONCLUSIONS: There is obvious proteomic change in lymphocytes of scalded rabbits or of scalded rabbits invaded by SA, and it may relate to immune suppression and sepsis after injury.
