1.Inhibitory effects of seabuckthorn polysaccharide on oxidative stress in mice with actue liver injury and modulatory effect on BCL-2/Bax and PPAR-γexpression
Fang LIU ; Shimin ZHAO ; Wei ZHANG ; Jiming XIE ; Kai ZOU ; Xiaohui ZHANG ; Xue WANG ; Huan LIU ; Junna CHEN ; Yuzhen WANG
Chinese Journal of Immunology 2016;32(3):358-361
Objective:To explore the inhibitory effects of seabuckthorn polysaccharide on hepatic oxidative stress in a mice model of acute liver injury induced by intraperitoneal injection of LPS and D -GalN and detect the expression on hepatic BCL-2/Bax and PPAR-γ.Methods: C57BL/6 male mice were randomly divided into six groups:control group ( CTRL), model group ( L/G), dexamethasone positive control group ( DXM ) , low ( SPL ) , medium ( SPM ) and high dose group ( SPH ) of seabuckthorn polysaccharide.Mice in the SPL,SPM and SPH group were gavaged with 50,100 and 200 mg/kg seabuckthorn polysaccharide for 14 days respectively.Acute liver injury model were established by intraperitoneal injection of LPS (10 μg/kg) and D-GalN (700 mg/kg) .Serum and liver samples were collected 4 h after model establishment .Serum levels of ALT and AST and the content of MDA were de-tected.Hepatic expression of SOD 2 BCL-2 and Bax was determined by Western blot and the expression of PPAR-γwas detected by im-munohistochemistry .Results:ALT and AST levels significantly increased in the model group and decreased dose-dependently after pre-treatment with seabuckthorn polysaccharide .The level of MDA in the model group increased significantly as compared with the control group and decreased in seabuckthorn polysaccharide groups ,while the level of SOD 2 decreased in the model group and recovered in sea-buckthorn polysaccharide groups .The expression of Bax decreased after pretreatment with seabuckthorn polysaccharide .There was no obvious effect on BCL-2 expression after sea buckthorn polysaccharide supplementation .The expression of PPAR-γreduced in the sea-buckthorn polysaccharide group as compared with the model group .Conclusion:Seabuckthorn polysaccharide protects against LPS /D-GalN-induced liver injury.The effect is associated with an upregulation of SOD 2 and downregulation of Bax .
2.Rab5a promotes expression of pro-inflammatory cytokines and type Ⅰ IFN in CpG induced macrophages
Junna CHEN ; Xiaolin SUN ; Shichao DONG ; Kai ZOU ; Huan LIU ; Yan WANG ; Xue WANG ; Fang LIU ; Jiming XIE ; Yuzhen WANG
Chinese Journal of Immunology 2016;(2):165-168
Objective:Using the macrophage cell lines RAW264.7 stably expressing Rab5a and its dominant negative mutant Rab5aN133I as models to analyze the effect and the mechanism of Rab 5a,Rab5aN133I on CpG-induced production of pro-inflammatory cytokines and type Ⅰ IFN.Methods: The eukaryotic expression vectors of Rab5a and Rab5aN133I were transfected into RAW264.7 cells by liposome,and screened with G418.The G418-resistant colonies were obtained and amplified.The transformed cell lines were i-dentified by RT-PCR,Real time-PCR and Western blot.The production of cytokines were measured after transformed cell lines of Rab5a and Rab5aN133I was stimulation with CpG for 8 h.Results: Rab5a expression in transfected cells was significantly higher than the control cell group (P<0.05).Overexpression of Rab5a significantly promoted the production of TNF -α,IL1-β(P<0.01) and IFN-β( P<0.05) in CpG stimulated RAW264.7.The production of cytokines was restored in Rab 5aN133I transfected cell line.Conclusion:Rab 5a promotes CpG-induced pro-inflammatory cytokines and typeⅠIFN in macrophages,it may be act as a positive regulator in TLR9 signaling pathway.
3.Optimization for the preparation process of silver nanoparticles and their biological activity.
Junna ZOU ; Wenhuan LUO ; Shan WANG ; Yan WANG
Journal of Central South University(Medical Sciences) 2022;47(10):1398-1407
OBJECTIVES:
Recently, the use of biological synthesis of metal nanoparticles has attracted widespread attention. Researchers are trying to find a biological method to synthesize silver nanoparticles with little environmental pollution and easy preparation, and to explore the impact of preparation conditions on the synthesis of silver nanoparticles. This study aims to explore the biological synthesis of silver nanoparticles (AgNPs) with controllable size and good effect and to compare their biological activity with that of AgNPs prepared by chemical method.
METHODS:
In this study, AgNPs were prepared by biological method with water extract of Tricholomagambosum (WET) and cell-free supernatant of Lactobacillus crispatus (CFS) as reducing agent and protective agent, and silver nitrate solution as precursor. Meanwhile, AgNPs was synthesized by sodium citrate chemical method. The effects of temperature, pH, dosage of extraction solution and light conditions on the biosynthesis of WET-AgNPs and CFS-AgNPs were investigated, and their characteristic of the synthesized WET-AgNPs and CFS-AgNPs were analyzed. Finally, the antibacterial effect, toxicity and selectivity of the 3 different AgNPs were compared.
RESULTS:
AgNPs were synthesized successfully by the 3 methods with various characteristics. The AgNPs prepared by biological method (WET-AgNPs , CFS-AgNPs) were greatly affected by pH and temperature. The WET-AgNPs and CFS-AgNPs prepared by the biological methods had better antibacterial effect than the AgNPs by the chemical method (all P<0.01). Between them, the WET-AgNPs had a slightly higher antibacterial effect than the CFS-AgNPs. Compared with the AgNPs prepared by chemical method, the toxicity of the WET-AgNPs and CFS-AgNPs to normal cells was lower (both P<0.01), and the cell selectivity of the CFS-AgNPs was better when the concentration was 480 μg/mL.
CONCLUSIONS
AgNPs with biological activity can be synthesized from WET and CFS, which have different biological activity compared with the AgNPs prepared by biological method.
Humans
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Metal Nanoparticles
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Fatigue Syndrome, Chronic
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Silver/pharmacology*
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Anti-Bacterial Agents/pharmacology*
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Plant Extracts/pharmacology*