Yuan-Jin Guo

Preliminary exploration on anti-inflammatory mechanism of Corilagin (beta-1-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-d-glucose) in vitro

Corilagin (beta-1-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-D-glucose) is a novel member of the tannin family which has been discovered from many medicinal plants and has been confirmed in many pharmacological activities. However, the purified Corilagin that was used in experiment is rare, and the anti-inflammatory mechanism of Corilagin has not been investigated clearly. This study is to explore the inner anti-inflammatory mechanism of Corilagin. Inflammatory cellular model was established by lipopolysaccharide (LPS) interfering on RAW264.7 cell line. Levels of TNF-alpha, IL-1beta, IL-6, NO and IL-10 in supernatant, mRNA expression of TNF-alpha, COX-2, iNOS and HO-1, protein expression of COX-2 and HO-1, translocation of NF-kappaB were assayed by ELISA or Griess method, real-time quantitative PCR, western blot and immunocytochemistry method, respectively. As a result, Corilagin could significantly reduce production of pro-inflammatory cytokines and mediators TNF-alpha, IL-1beta, IL-6, NO (iNOS) and COX-2 on both protein and gene level by blocking NF-kappaB nuclear translocation. Meanwhile Corilagin could notably promote release of anti-inflammatory factor HO-1 on both protein and gene level, but suppress the release of IL-10. In conclusion, the anti-inflammatory effects of Corilagin are attributed to the suppression of pro-inflammatory cytokines and mediators by blocking NF-kappaB activation. Corilagin also can promote HO-1 production to induce regression of inflammation but can inhibit IL-10 production like Dexamethasone. Corilagin possesses a potential anti-inflammatory effect by not only abating inflammatory impairment but also promoting regression of inflammation and has a good prospect to be used in many inflammation-related diseases.

Influence of Etoposide on anti-apoptotic and multidrug resistance-associated protein genes in CD133 positive U251 glioblastoma stem-like cells.

It has been hypothesized that cancer stem cell is responsible for the refractoriness of glioblastoma therapy. This study is to observe the influence of Etoposide on anti-apoptotic and multidrug resistance-associated protein genes in glioblastoma stem-like cells. U251 glioblastoma cells were cultured and CD133 positive cancer stem-like cells were isolated and identified. Cell counting kit-8 assay, cell morphology and flow cytometry were employed for assaying cell survival condition. Real-time quantitative PCR was chosen for detecting mRNA expression of livin, livinalpha, livinbeta, survivin, MRP1 and MRP3. As results, after Etoposide intervention, the U251 stem-like cells showed more resistant property, more intact morphology and lower apoptotic rate than that in U251 cells (p<0.05). It could be found that the expression of livinbeta in U251 stem-like cells was significantly higher (p<0.05). After Etoposide intervention, only livinalpha was suppressed markedly (p<0.05), while livin expression was not notably decreased with livinbeta increased on the contrary (p<0.05). MRP1 and MRP3 in U251 stem-like cells were significantly higher than that in cancer cells, and after chemotherapy, the expression of MRP1 increased notably (p<0.05). But the expression of survivin and MRP3 did not show these features. In conclusion, after Etoposide intervention glioblastoma stem-like cells showed a stronger resistance to apoptosis and death, and the anti-apoptotic gene livinbeta was more related with the high survival rate and MRP1 appeared to be more related with transporting chemotherapeutics out of glioblastoma stem-like cells.

Effect of Corilagin on anti-inflammation in HSV-1 encephalitis and HSV-1 infected microglias.

The aim of this explore is to study the anti-inflammatory effect of Corilagin in herpes simplex virus (HSV)-1 infected microglial cells and HSV-1 infected mouse brain. The cellular model was set with microglial cells stimulated by HSV-1 and divided respectively, into virus, astragalus polysaccharides (APS), Dexamethasone and Corilagin group. A normal control group consisting of uninfected microglial cells was also included. ELISA for measuring TNF-alpha, IL-1beta and IL-10 and Greiss method for detecting NO secretion in supernatant, flow cytometry assay for examining apoptosis rate, expression of caspase-3, caspase-8, caspase-9 and caspase-12, and western-blot for measuring protein expression of cytochrome c were performed. The animal model was set up using Balb/c male mice that were intracranially inoculated with HSV-1. Animals were then divided in groups as described for the cellular model. Here, too a normal control group was included. HE staining was used to assay pathological changes in brain. As results, after Corilagin intervention, the release of TNF-alpha, IL-1beta and NO from HSV-stimulated migroglia cells was significantly inhibited. Furthermore, Corilagin induced apoptosis of HSV-stimulated microglia through all the 3 known apoptotic pathways. The animal model treated with Corilagin also displayed significant decrease of herpes simplex encephalitis induced brain pathological changes. In conclusion, Corilagin has the potential to reduce HSV-1-induced inflammatory insult to the brain, and its mode of action is through the induction of apoptosis of microglias and reduction of cytokines production.

Anti-inflammatory and anti-oxidative effects of corilagin in a rat model of acute cholestasis.

BackgroundNowadays, treatments for cholestasis remain largely nonspecific and often ineffective. Recent studies showed that inflammatory injuries and oxidative stress occur in the liver with cholestasis. In this study, we would use corilagin to treat the animal model of acute cholestasis in order to define the activity to interfere with inflammation-related and oxidative stress pathway in cholestatic pathogenesis.MethodsRats were administrated with alpha-naphthylisothiocyanate to establish model of cholestasis and divided into corilagin, ursodeoxycholic acid, dexamethasone, model and normal groups with treatment of related agent. At 24h, 48h and 72h time points after administration, living condition, serum markers of liver damage, pathological changes of hepatic tissue, nuclear factor (NF)-kappaB, myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD) and nitric oxide (NO) were examined and observed.ResultsCompared to model group, corilagin had remarkable effect on living condition, pathological manifestation of liver tissue, total bilirubin, direct bilirubin, (P<0.01), but no effect on alanine aminotransferase (ALT) and aspartate aminotransferase (AST). With corilagin intervention, levels of MPO, MDA and translocation of NF-κB were notably decreased, and levels of SOD and NO were markedly increased (P<0.05 or P<0.01).ConclusionsIt is shown that corilagin is a potential component to relieve cholestasis through inflammation-related and oxidation-related pathway.

Involvement of TLR2 and TLR9 in the anti-inflammatory effects of chlorogenic acid in HSV-1-infected microglia

AIMS There is no effective medication to date for herpes simplex virus encephalitis (HSE). In this study, we investigated the anti-inflammatory effect of chlorogenic acid (CGA) on herpes simplex virus (HSV)-1-induced responses in BV2 microglia. MAIN METHODS The cellular model was established with BV2 cells stimulated by HSV-1 and then treated with CGA at different concentrations. Cell viability was assayed by the MTT assay. The mRNA expression of Toll-like receptor (TLR)-2, TLR9 and myeloid differentiation factor88 (Myd88) was assayed by real-time quantitative PCR, and the protein expression was assayed by flow cytometry or Western blotting. Tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 were measured by ELISA as well as real-time quantitative PCR. Nuclear NF-κB p65 protein was assayed by Western blotting. KEY FINDINGS The cell survival rate was significantly improved after CGA treatment, and CGA prevented increases in TLR2, TLR9 and Myd88 following HSV-1 challenge in BV2 cells both at the mRNA and protein levels. Moreover, CGA could attenuate HSV-induced TNF-α and IL-6 release into the supernatant. The mRNA levels of TNF-α and IL-6 were also significantly inhibited by CGA. The expression of NF-κB p65 increased significantly in the nucleus in HSV-1-stimulated microglia but could be reduced by CGA. SIGNIFICANCE CGA inhibits the inflammatory reaction in HSE via the suppression of TLR2/TLR9-Myd88 signaling pathways. CGA may serve as an anti-inflammatory agent and provide a new strategy for treating HSE.

Corilagin Protects Against HSV1 Encephalitis Through Inhibiting the TLR2 Signaling Pathways In Vivo and In Vitro

In this study, we tried to explore the molecular mechanism that Corilagin protected against herpes simplex virus-1 encephalitis through inhibiting the TLR2 signaling pathways in vivo and in vitro. As a result, Corilagin significantly prevented increase in the levels of TLR2 and its downstream mediators following Malp2 or HSV-1 challenge. On the other hand, in spite of TLR2 knockdown, Corilagin could still significantly suppress the expression of P38 and NEMO, phosphor-P38, and nuclear factor kappa B. The mRNA and protein expression of TLR2 and its downstream mediators in the brain tissue were also significantly lowered in mice treated with Corilagin. In addition, Corilagin inhibited expression of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 protein. In conclusion, Corilagin shows the potential to protect against HSV-1-induced encephalitis, and the beneficial effects may be mediated by inhibiting TLR2 signaling pathways.

Anti-inflammatory mechanism of a folk herbal medicine, Duchesnea indica (Andr) Focke at RAW264.7 cell line.

This study is to explore the anti-inflammatory mechanism of the ethanol extract of Duchesnea indica (Andr) Focke. An inflammatory cellular model was established by addition of lipopolysaccharide (LPS) on RAW264.7 cell line. The cellular secretion of TNF-α, IL-1β, IL-6, NO and IL-10 in supernatant, mRNA expression of TNF-α, COX-2, iNOS and HO-1, protein expression of COX-2 and HO-1, and activation of NF-κB were assayed by ELISA, the Griess method, real-time quantitative PCR, and Western blot and immunocytochemistry method, respectively. The ethanol extract of D. indica not only reduced production of pro-inflammatory cytokines and mediators and blocked NF-κB activation, but also slightly promoted release of the anti-inflammatory mediator HO-1 and suppressed IL-10 secretion. In conclusion, the anti-inflammatory effects of the extract of D. indica are attributed to the suppression of pro-inflammatory cytokines and mediators by blocking NF-κB activation. The extract of D. indica can also slightly promote HO-1 production to reduce inflammation.

Inducing-apoptotic activity of the ethanol extract of Duchesnea indica Focke on treatment of herpes simplex encephalitis.

This study explores the inducing-apoptotic activity of the ethanol extract of Duchesnea indica Focke on treatment of herpes simplex encephalitis. Cell models were employed and divided into 4 groups: normal group, virus group, Duchesnea indica group and dexamethasone group. Cytopathic effect examination was employed to detect apoptosis of PC-12 and BV-2 cells. ELISA was used to measure TNF-α and IL-1β, and Greiss method to measure NO secretion. Flow cytometry assay for caspase-3 expressions was performed. As a result, the ethanol extract of Duchesnea indica could protect the neuron cell model from impairment by virus. In the cell model of microglia stimulated by herpes simplex virus (HSV), with the ethanol extract intervention, TNF-α, IL-1β and NO levels were significantly decreased and cell death of BV-2 cells were markedly increased. The expression level of caspase-3 was notably elevated after the extract intervention. In conclusion, the ethanol extract of Duchesnea indica can reduce HSV-induced inflammatory injury on neuron due to the induction of microglia apoptosis.

Protective activity of the ethanol extract of Cynanchum paniculatum (BUNGE) Kitagawa on treating herpes simplex encephalitis.

To date there has been no valid treatment for herpes simplex encephalitis (HSV). This study explores the protective activity of ethanol extract of Cynanchum paniculatum (bunge) kitagawa for treatment of HSV. Cell models and animal models were established and divided into 4 groups: normal group, virus group, cynanchum paniculatum group and Dexamethasone group. Flow cytometry was employed to detect apoptosis of cell model and TUNEL assay was chosen to detect apoptosis of animal tissues. The survival time of the animal models was observed. ELISA was used to measure TNF-α expression and the Greiss method to measure Nitric Oxide (NO) expression in the mouse brain. As a result, it was found that extract of Cynanchum paniculatum can improve the survival rate of HSV-infected mice. The extract could prevent apoptosis in the neuron cell model and reduce apoptosis rate in brain tissue after HSV infection. With the extract intervention, TNF-α and NO levels in brain tissue were significantly decreased in the animal model. In conclusion, the extract of Cynanchum paniculatum can prevent HSV-inducing impairment in the cell and animal model of HSE.

Anti-inflammatory Mechanism of Rungia pectinata (Linn.) Nees

This study is to explore the inner anti-inflammatory mechanism of the ethanol extract of Rungia pectinata (Linn.) Nees. As a result, the ethanol extract of Rungia pectinata (Linn.) Nees could not only strongly reduce production of pro-inflammatory cytokines and mediators via blocking NF-κB activation but slightly promote release of anti-inflammatory mediator HO-1 and suppress IL-10 secretion. In conclusion, compared to Dexamethasone, Rungia pectinata (Linn.) Nees has not only similar effects on antagonizing pro-inflammatory mediators and cytokines but also mild effects on promoting production of anti-inflammatory mediators.