Previous studies have confirmed that oxidized adenosine triphosphate, a P2X7 receptor antagonist, attenuates lipopolysaccharide-mediated microglial activation and inflammatory expression following neuronal damage in r...Previous studies have confirmed that oxidized adenosine triphosphate, a P2X7 receptor antagonist, attenuates lipopolysaccharide-mediated microglial activation and inflammatory expression following neuronal damage in rat brain. NaCI and temperature may affect the potency of oxidized adenosine triphosphate. Brilliant blue G is a derivative of a widely used food additive and has little toxicity. This study explored the effects of brilliant blue G, a selective P2X7 receptor antagonist, on microglial activation and inflammation. Results demonstrated that brilliant blue G inhibited the release of cydooxygenase-2 and interleukin-6 in BV2 cells. Immunofluorescence displayed that brilliant blue G could suppress lipopolysaccharide-induced microglial activation. This study used RNA interference to block P2X7 receptor expression and found that small interfering RNA also suppressed the release of cyclooxygenase-2 and interleukin-6 in BV2 cells. These results suggested that downregulation of the P2X7 receptor by brilliant blue G was involved in the inhibition of microglial activation and inflammation.展开更多
The gram-negative bacterium Helicobacter pylori(H. pylori) infects the stomachs of approximately half of the world's population. Although infection induces an immune response that contributes to chronic gastric in...The gram-negative bacterium Helicobacter pylori(H. pylori) infects the stomachs of approximately half of the world's population. Although infection induces an immune response that contributes to chronic gastric inflammation, the response is not sufficient to eliminate the bacterium. H. pylori infection causes peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Disease outcome is linked to the severity of the host inflammatory response. Gastric epithelial cells represent the first line of innate immune defence against H. pylori, and respond to infection by initiating numerous cell signalling cascades, resulting in cytokine induction and the subsequent recruitment of inflamma-tory cells to the gastric mucosa. Pathogen recognition receptors of the toll-like receptor(TLR) family mediate many of these cell signalling events. This review dis-cusses recent findings on the role of various TLRs in the recognition of H. pylori in distinct cell types, describes the TLRs responsible for the recognition of individual H. pylori components and outlines the influence of innate immune activation on the subsequent development of the adaptive immune response. The mechanistic iden-tification of host mediators of H. pylori-induced patho-genesis has the potential to reveal drug targets and opportunities for therapeutic intervention or prevention of H. pylori-associated disease by means of vaccines or immunomodulatory therapy.展开更多
This study investigated the expression and immune effect of TLR4 in human trophoblast cells. The expression level of TLR4 mRNA in normal and LPS-stimulated human term trophoblast cells （1 mg/L LPS, 12 h） was detecte...This study investigated the expression and immune effect of TLR4 in human trophoblast cells. The expression level of TLR4 mRNA in normal and LPS-stimulated human term trophoblast cells （1 mg/L LPS, 12 h） was detected by RT-PCR. In LPS-stimulated human term trophoblast cells of TLR4-blocked group and non-TLR4-blocked group, and normal term trophoblast cells of blank control group, apoptosis rate was measured by flow cytometry （FCM）, and the level of TNF-α determined by using enzyme linked immunosorbent assay （ELISA） respectively. RT-PCR results showed that the expression level of TLR4 mRNA in LPS-stimulated human trophoblast cells was significantly higher than that in normal cells （P〈0.01）. FCM revealed that there was significant difference in apoptosis rate of LPS-stimulated human term trophoblast cells between TLR4-blocked group and non-TLR4-blocked group （P〈0.05）, or between TLR4 antibody-blocked group and blank control group. ELISA indicated that the level of TNF-α in LPS-stimulated human trophoblast cells also had statistical differences between TLR4 antibody-blocked group and non-TLR4 antibody-blocked group （P〈0.05）. Our results suggest that TLR4 plays an important role in the immunological mechanism of apoptosis and secretion of TNF-α of human term trophoblast cells stimulated by LPS.展开更多
AIM： To evaluate the effect of Chinese traditional medicinal prescription, JIANPI HUOXUE decoction （JHD） on cytokine secretion pathway in rat liver induced by lipopolysaccharide （LPS）. METHODS： Twenty-four male ...AIM： To evaluate the effect of Chinese traditional medicinal prescription, JIANPI HUOXUE decoction （JHD） on cytokine secretion pathway in rat liver induced by lipopolysaccharide （LPS）. METHODS： Twenty-four male SD rats were divided into normal group （n = 4）, model group （n = 10） and JHD group （n = 10） randomly. Rats in model group and JHD group were administrated with normal saline or JHD via gastrogavage respectively twice a day for 3 d. One hour after the last administration, rats were injected with LPS via tail vein, 50 μg/kg. Simultaneously, rats in normal group were injected with equivalent normal saline. After LPS stimulation for 1.5 h, serum and liver tissue were collected. Pathological change of liver tissues was observed through hematoxylineosin （H.E.） staining. Tumor necrosis factor alpha （TNF-α） in serum were assayed by enzyme linked immunosorbent assay （ELISA）. The protein expression of TNF-α, phosphorylated inhibit-κB （p-κB） and CD68 in liver were assayed by Western blot. The distribution of CD68 protein in liver was observed through immunohistochemical staining. The mRNA expression of TNF-α, interleukin-6 （IL-6）, CD14, toll-like receptor 2 （TLR2） and TLR4 in liver were assayed by real-time RT-PCR.RESULTS： Predominant microvesicular change, hepatocyte tumefaction and cytoplasm dilution were observed in liver tissues after LPS administration as well as obvious CD68 positive staining in hepatic sinusoidal. After LPS stimulation, serum TNF-α （31.35 ± 6.06 vs 12225.40 ± 9007.03, P 〈 0.05）, protein expression of CD68 （1.13 ± 0.49 vs 3.36 ±1.69, P 〈 0.05）, p-IκB （0.01 ±0.01 vs 2.07 ＋ 0.83, P 〈 0.01） and TNF-α （0.27 ± 0.13 vs 1.29 ± 0.37, P 〈 0.01） in liver and mRNA expression of TNF-α （1.96 ± 2.23 vs 21.45 ±6.00, P 〈 0.01）, IL-6 （4.80 ± 6.42 vs 193.50 ± 36.36, P 〈 0.01） and TLR2 （1.44 ± 0.62 vs 4.16 ± 0.08, P 〈 0.01） in liver were also increased significantly. These pathological changes were all improved in .1HD group. On the other hand, TLR4 mRNA （1.22 ± 0.30 vs 0.50 ± 0.15, P 〈 0.05） was down-regulated and CD14 mRNA increased but not significantly after LPS stimulation. CONCLUSION： JHD can inhibit cytokine secretion pathway induced by LPS in rat liver, which is probably associated with its regulation on CD68, p-IκB and endotoxin receptor TLR2.展开更多
OBJECTIVE: To assess the effect of lipopolysaccharides (LPS) on the expression of CD14 and TLR4 in rat Kupffer cells (KCs). METHODS: In rat KCs induced by LPS, the changes of CD14 and TLR4 expression were measured by ...OBJECTIVE: To assess the effect of lipopolysaccharides (LPS) on the expression of CD14 and TLR4 in rat Kupffer cells (KCs). METHODS: In rat KCs induced by LPS, the changes of CD14 and TLR4 expression were measured by RT-PCR and immunohistochemistry, and the expressions of TNF-αmRNA, IL-6mRNA or the concentrations of TNF-α, IL-6 were estimated by in situ hybridization, radioimmunoassay, and others. RESULTS: The expressions of CD14 and TLR4 in KCs induced by LPS were markedly increased in a dose-dependent manner (10 mg/L-1μg/L) or in a time-dependent manner (0.5 h-24 h), with the peaked expression of CD14 at 3-6 hours. The expressions of CD14 and TLR4 in KCs stimulated by the active mediators from KCs which had been exposed to LPS for 1 hour were obviously increased. CONCLUSIONS: There is a close relationship between LPS or the active mediators from KCs induced by LPS and the expressions of CD14, TLR4. It is implied that the increase of TLR4, CD14 expression may be induced by LPS within 1--3 hours, and further increase of TLR4, CD14 expression may be correlated with the cytokines produced bv KCs.展开更多
Parkinson's disease,the most common movement disorder,has a strong neuroinflammatory aspect.This is evident by increased pro-inflammatory cytokines in the serum,and the presence of activated microglial cells,and i...Parkinson's disease,the most common movement disorder,has a strong neuroinflammatory aspect.This is evident by increased pro-inflammatory cytokines in the serum,and the presence of activated microglial cells,and inflammatory cytokines in the substantia nigra of post-mortem brains as well as cerebrospinal fluid of Parkinson's disease patients.The central and peripheral neuroinflammatory aspects of Parkinson's disease can be investigated in vivo via administration of the inflammagen lipopolysaccharide,a component of the cell wall of gram-negative bacteria.In this mini-review,we will critically evaluate different routes of lipopolysaccharide administration(including intranasal systemic and ste reotasic),their relevance to clinical Parkinson's disease as well as the recent findings in lipopolysaccharide mouse models.We will also share our own expe riences with systemic and intrastriatal lipopolysaccharide models in C57BL/6 mice and will discuss the usefulness of lipopolysaccharide mouse models for future research in the field.展开更多
BACKGROUND Budd-Chiari syndrome(BCS)is an uncommon disorder characterized by obstruction of hepatic venous outflow.To date,the exact mechanism underlying hepatic injury derived from the hepatic venous outflow obstruct...BACKGROUND Budd-Chiari syndrome(BCS)is an uncommon disorder characterized by obstruction of hepatic venous outflow.To date,the exact mechanism underlying hepatic injury derived from the hepatic venous outflow obstruction in BCS remains largely unknown.AIM To assess the role of NF-κB-mediated inflammation in BCS-induced liver injury in humans and rats.METHODS A total of 180 rats were randomly assigned into nine groups,including four BCS model groups(1,3,6 and 12 wk),four sham-operated groups(1,3,6 and 12 wk),and a control group.Lipopolysaccharide(LPS)levels in each group were detected by the Tachypleus Amebocyte Lysate assay.The mRNA and protein levels of TLR4,NF-κB,tumor necrosis factor(TNF)-α,interleukin(IL)-2 and interferon(IFN)-γwere quantified.In addition,60 patients with BCS and 30 healthy controls were enrolled,and their blood samples were analyzed.RESULTS Hepatic and plasma LPS levels were significantly increased in rats.The mRNA and protein expression levels of TLR4,NF-κB and inflammatory cytokines(TNF-α,IL-2 and IFN-γ)in liver tissues were significantly higher in the BCS model groups compared with the other two groups.In addition,the model groups(1,3,6 and 12 wk after BCS induction)showed significant differences in the levels of LPS,TLR4,NF-κB,TNF-α,IL-2 and IFN-γ.Notably,there was a significant correlation between the LPS concentrations and mRNA and protein levels of TLR4,NF-κB and inflammatory cytokines.Importantly,it was revealed that the levels of LPS,TLR4,NF-κB and inflammatory cytokines were significantly greater in chronic BCS patients than healthy controls and acute BCS patients.CONCLUSION LPS level is markedly elevated in BCS,in turn activating the TLR4/NF-κB signaling pathway,leading to induction of inflammatory cytokines(TNF-α,IL-2 and IFN-γ)in response to BCS-induced liver injury.展开更多
基金supported by the National Natural Science Foundation of China, No. 81072242the Excellent Supervisor & Yat-Sen Creative Talent Development Program of Sun Yat-sen University
文摘Previous studies have confirmed that oxidized adenosine triphosphate, a P2X7 receptor antagonist, attenuates lipopolysaccharide-mediated microglial activation and inflammatory expression following neuronal damage in rat brain. NaCI and temperature may affect the potency of oxidized adenosine triphosphate. Brilliant blue G is a derivative of a widely used food additive and has little toxicity. This study explored the effects of brilliant blue G, a selective P2X7 receptor antagonist, on microglial activation and inflammation. Results demonstrated that brilliant blue G inhibited the release of cydooxygenase-2 and interleukin-6 in BV2 cells. Immunofluorescence displayed that brilliant blue G could suppress lipopolysaccharide-induced microglial activation. This study used RNA interference to block P2X7 receptor expression and found that small interfering RNA also suppressed the release of cyclooxygenase-2 and interleukin-6 in BV2 cells. These results suggested that downregulation of the P2X7 receptor by brilliant blue G was involved in the inhibition of microglial activation and inflammation.
文摘The gram-negative bacterium Helicobacter pylori(H. pylori) infects the stomachs of approximately half of the world's population. Although infection induces an immune response that contributes to chronic gastric inflammation, the response is not sufficient to eliminate the bacterium. H. pylori infection causes peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Disease outcome is linked to the severity of the host inflammatory response. Gastric epithelial cells represent the first line of innate immune defence against H. pylori, and respond to infection by initiating numerous cell signalling cascades, resulting in cytokine induction and the subsequent recruitment of inflamma-tory cells to the gastric mucosa. Pathogen recognition receptors of the toll-like receptor(TLR) family mediate many of these cell signalling events. This review dis-cusses recent findings on the role of various TLRs in the recognition of H. pylori in distinct cell types, describes the TLRs responsible for the recognition of individual H. pylori components and outlines the influence of innate immune activation on the subsequent development of the adaptive immune response. The mechanistic iden-tification of host mediators of H. pylori-induced patho-genesis has the potential to reveal drug targets and opportunities for therapeutic intervention or prevention of H. pylori-associated disease by means of vaccines or immunomodulatory therapy.
文摘This study investigated the expression and immune effect of TLR4 in human trophoblast cells. The expression level of TLR4 mRNA in normal and LPS-stimulated human term trophoblast cells （1 mg/L LPS, 12 h） was detected by RT-PCR. In LPS-stimulated human term trophoblast cells of TLR4-blocked group and non-TLR4-blocked group, and normal term trophoblast cells of blank control group, apoptosis rate was measured by flow cytometry （FCM）, and the level of TNF-α determined by using enzyme linked immunosorbent assay （ELISA） respectively. RT-PCR results showed that the expression level of TLR4 mRNA in LPS-stimulated human trophoblast cells was significantly higher than that in normal cells （P〈0.01）. FCM revealed that there was significant difference in apoptosis rate of LPS-stimulated human term trophoblast cells between TLR4-blocked group and non-TLR4-blocked group （P〈0.05）, or between TLR4 antibody-blocked group and blank control group. ELISA indicated that the level of TNF-α in LPS-stimulated human trophoblast cells also had statistical differences between TLR4 antibody-blocked group and non-TLR4 antibody-blocked group （P〈0.05）. Our results suggest that TLR4 plays an important role in the immunological mechanism of apoptosis and secretion of TNF-α of human term trophoblast cells stimulated by LPS.
基金Supported by The National Natural Science Foundation of China, No.30371818Shanghai Rising-Star Program, No. 07QA14052Shanghai Leading Academic Discipline Project, Y0302 and Shanghai Educational Development Foundation, No. 2007CG56
文摘AIM： To evaluate the effect of Chinese traditional medicinal prescription, JIANPI HUOXUE decoction （JHD） on cytokine secretion pathway in rat liver induced by lipopolysaccharide （LPS）. METHODS： Twenty-four male SD rats were divided into normal group （n = 4）, model group （n = 10） and JHD group （n = 10） randomly. Rats in model group and JHD group were administrated with normal saline or JHD via gastrogavage respectively twice a day for 3 d. One hour after the last administration, rats were injected with LPS via tail vein, 50 μg/kg. Simultaneously, rats in normal group were injected with equivalent normal saline. After LPS stimulation for 1.5 h, serum and liver tissue were collected. Pathological change of liver tissues was observed through hematoxylineosin （H.E.） staining. Tumor necrosis factor alpha （TNF-α） in serum were assayed by enzyme linked immunosorbent assay （ELISA）. The protein expression of TNF-α, phosphorylated inhibit-κB （p-κB） and CD68 in liver were assayed by Western blot. The distribution of CD68 protein in liver was observed through immunohistochemical staining. The mRNA expression of TNF-α, interleukin-6 （IL-6）, CD14, toll-like receptor 2 （TLR2） and TLR4 in liver were assayed by real-time RT-PCR.RESULTS： Predominant microvesicular change, hepatocyte tumefaction and cytoplasm dilution were observed in liver tissues after LPS administration as well as obvious CD68 positive staining in hepatic sinusoidal. After LPS stimulation, serum TNF-α （31.35 ± 6.06 vs 12225.40 ± 9007.03, P 〈 0.05）, protein expression of CD68 （1.13 ± 0.49 vs 3.36 ±1.69, P 〈 0.05）, p-IκB （0.01 ±0.01 vs 2.07 ＋ 0.83, P 〈 0.01） and TNF-α （0.27 ± 0.13 vs 1.29 ± 0.37, P 〈 0.01） in liver and mRNA expression of TNF-α （1.96 ± 2.23 vs 21.45 ±6.00, P 〈 0.01）, IL-6 （4.80 ± 6.42 vs 193.50 ± 36.36, P 〈 0.01） and TLR2 （1.44 ± 0.62 vs 4.16 ± 0.08, P 〈 0.01） in liver were also increased significantly. These pathological changes were all improved in .1HD group. On the other hand, TLR4 mRNA （1.22 ± 0.30 vs 0.50 ± 0.15, P 〈 0.05） was down-regulated and CD14 mRNA increased but not significantly after LPS stimulation. CONCLUSION： JHD can inhibit cytokine secretion pathway induced by LPS in rat liver, which is probably associated with its regulation on CD68, p-IκB and endotoxin receptor TLR2.
文摘OBJECTIVE: To assess the effect of lipopolysaccharides (LPS) on the expression of CD14 and TLR4 in rat Kupffer cells (KCs). METHODS: In rat KCs induced by LPS, the changes of CD14 and TLR4 expression were measured by RT-PCR and immunohistochemistry, and the expressions of TNF-αmRNA, IL-6mRNA or the concentrations of TNF-α, IL-6 were estimated by in situ hybridization, radioimmunoassay, and others. RESULTS: The expressions of CD14 and TLR4 in KCs induced by LPS were markedly increased in a dose-dependent manner (10 mg/L-1μg/L) or in a time-dependent manner (0.5 h-24 h), with the peaked expression of CD14 at 3-6 hours. The expressions of CD14 and TLR4 in KCs stimulated by the active mediators from KCs which had been exposed to LPS for 1 hour were obviously increased. CONCLUSIONS: There is a close relationship between LPS or the active mediators from KCs induced by LPS and the expressions of CD14, TLR4. It is implied that the increase of TLR4, CD14 expression may be induced by LPS within 1--3 hours, and further increase of TLR4, CD14 expression may be correlated with the cytokines produced bv KCs.
文摘Parkinson's disease,the most common movement disorder,has a strong neuroinflammatory aspect.This is evident by increased pro-inflammatory cytokines in the serum,and the presence of activated microglial cells,and inflammatory cytokines in the substantia nigra of post-mortem brains as well as cerebrospinal fluid of Parkinson's disease patients.The central and peripheral neuroinflammatory aspects of Parkinson's disease can be investigated in vivo via administration of the inflammagen lipopolysaccharide,a component of the cell wall of gram-negative bacteria.In this mini-review,we will critically evaluate different routes of lipopolysaccharide administration(including intranasal systemic and ste reotasic),their relevance to clinical Parkinson's disease as well as the recent findings in lipopolysaccharide mouse models.We will also share our own expe riences with systemic and intrastriatal lipopolysaccharide models in C57BL/6 mice and will discuss the usefulness of lipopolysaccharide mouse models for future research in the field.
基金Natural Science Foundation Project of Anhui Province,No.1708085QH218。
文摘BACKGROUND Budd-Chiari syndrome(BCS)is an uncommon disorder characterized by obstruction of hepatic venous outflow.To date,the exact mechanism underlying hepatic injury derived from the hepatic venous outflow obstruction in BCS remains largely unknown.AIM To assess the role of NF-κB-mediated inflammation in BCS-induced liver injury in humans and rats.METHODS A total of 180 rats were randomly assigned into nine groups,including four BCS model groups(1,3,6 and 12 wk),four sham-operated groups(1,3,6 and 12 wk),and a control group.Lipopolysaccharide(LPS)levels in each group were detected by the Tachypleus Amebocyte Lysate assay.The mRNA and protein levels of TLR4,NF-κB,tumor necrosis factor(TNF)-α,interleukin(IL)-2 and interferon(IFN)-γwere quantified.In addition,60 patients with BCS and 30 healthy controls were enrolled,and their blood samples were analyzed.RESULTS Hepatic and plasma LPS levels were significantly increased in rats.The mRNA and protein expression levels of TLR4,NF-κB and inflammatory cytokines(TNF-α,IL-2 and IFN-γ)in liver tissues were significantly higher in the BCS model groups compared with the other two groups.In addition,the model groups(1,3,6 and 12 wk after BCS induction)showed significant differences in the levels of LPS,TLR4,NF-κB,TNF-α,IL-2 and IFN-γ.Notably,there was a significant correlation between the LPS concentrations and mRNA and protein levels of TLR4,NF-κB and inflammatory cytokines.Importantly,it was revealed that the levels of LPS,TLR4,NF-κB and inflammatory cytokines were significantly greater in chronic BCS patients than healthy controls and acute BCS patients.CONCLUSION LPS level is markedly elevated in BCS,in turn activating the TLR4/NF-κB signaling pathway,leading to induction of inflammatory cytokines(TNF-α,IL-2 and IFN-γ)in response to BCS-induced liver injury.
