ABSTRACT
Objective To study the protective effect of Tripterygium wilfordii polycoride (TWP) against TNBS/ethanol-induced ulcerative colitis (UC) rat model. Methods TNBS and ethanol enema were adopted to build TNBS/ethanol-induced UC rat model. Ninety male Wistar rats were divided into six groups: normal, model, low-, medium-, high-dose TWP and azathioprine (AZA) groups, each for 15 rats. All rats were administered by corresponding medicine for 14 d. After 14 d, corresponding colon tissues underwent general and microscopic evaluation. Blood samples were taken from heart and serum was separated by centrifugation. MDA, SOD, GSH, IL-1β and TNF-α levels in serum were tested by ELISA. Colonic samples underwent RT-PCR and Western blotting analysis. Results DAI, general and microscopic evaluation all showed that TWP could promote colonic mucosa healing and such effect was equal to AZA. ELISA results about lipid peroxidation indicated that TWP could decrease MDA level and increase SOD and GSH levels in a dose-dependent manner. TWP with high dose could strongly decrease the MDA level and increase the SOD and GSH levels (P 0.05), whereas slightly stronger towards terminal inflammatory cytokines (P > 0.05). Conclusion TWP could significantly lower the infiltration of inflammatory cells under microscope, eventually led to mucosa healing, the mechanism of which was to inhibit lipid peroxidation, then further inhibit NF-κB activation, eventually lower the expression of inflammatory meditors locally and systemically.
ABSTRACT
In order to study the regulatory effect of Tripterygium wilfordii polycoride (TWP) towards TLR4/MyD88 independent pathway in TNBS/ethanol ulcerative colitis (UC) rat model, TNBS/ethanol enema was adopted to build TNBS/ethanol UC rat model. After the successful modeling procedure, 90 male Wistar rats are were divided into 6 groups, including namely normal group, model group, TWP low, middle, high dose groups (3, 6, 12 mg•kg⁻¹)and azathioprine (AZA) group (6 g•kg⁻¹), with 15 rats in each group. All rats in each group were administrated with corresponding medicines for 14 days. After 14 days of administration, corresponding colon tissues were taken for general and microscopic evaluation. Western blotting analysis and RT-PCR were adopted to test the mRNA and protein expressions of TLR4/MyD88 independent pathway-related molecules, namely TLR4, TRAM, TRIF, NF-κB and IFN-γ. The results showed that DAI, general and microscopic evaluations all indicated that TNBS/ethanol UC rat model was successful. TWP can improve UC-related clinical manifestation and heal colonic mucosa, which was equal to AZA. RT-PCR and WB results showed that the expression of TLR4/MyD88 independent pathway-related molecules in model group were significantly superior to that in normal group at either mRNA or protein level (P<0.01). Compared with model group, TWP can inhibit the expression of each node in TLR4/MyD88 independent pathway in a dose-dependent manner. The inhibitory effect of TWP with high dose towards the above molecules was inferior to that in model group at either mRNA or protein level (P<0.05). The inhibitory effect of TWP with high dose towards upstream molecules of TLR4/MyD88 independent pathway (TLR4, TRAM, TRIF, NF-κB) was slightly superior to AZA group at either mRNA or protein level. However, such inhibitory effect towards terminal inflammatory cytokines (IFN-γ) was inferior to AZA group at either mRNA or protein level. All the above differences had no statistical significance. Therefore, in TNBS/ethanol UC rat model, TLR4/MyD88 independent pathway took part in regulating inflammation. TWP exerted its anti-inflammation effect by inhibiting the expression of TLR4/MyD88 independent pathway in a dose-dependent manner.
ABSTRACT
Objective: To study the regulatory effect of Tripterygium wilfordii Polycoride Tadlet (TWPT) towards miR-146a, miR-146b, and TLR4/MyD88 dependent signaling pathway in TNBS/ethanol ulcerative colitis (UC) rat model. Methods: TNBS enema was adopted to build TNBS/ethanol UC rat model. After the modeling procedure, 90 male Wistar rats were divided into six groups, including normal, model, low-, mid-, high-dose TWPT, and azathioprine (AZA) groups, and each for 15 rats. All rats in each group were administered with corresponding medicines for 14 d. After 14 d administration, corresponding colon tissues were taken to undergo general and microscopic evaluation. qPCR was adopted to test the expression of miR-146a and miR-146b. Western blotting analysis and RT-PCR were adopted to test the mRNA and protein expression levels of TLR4/MyD88 dependent signaling pathway related molecular, including TLR4, MyD88, TRAF-6, NF-κB, TNF-α, and IL-1β. Results: DAI, general and microscopic evaluation all showed that TNBS/ethanol UC rat model was successfully established. TWPT could improve UC-related clinical manifestation and promote the colonic mucosa healing procedure and such effect was equal to AZA. qRT-PCR showed that the expression of miR-146a and miR-146b in model group was significantly superior to that in normal group (P 0.05). Conclusion: In TNBS/ethanol UC rat model, TWPT could inhibit the expression of miR-146a, miR-146b, and TLR4/MyD88 dependent signaling pathway. The inhibitory effect of TWPT towards pathway and inflammatory cytokines shows a dose-dependent manner.
ABSTRACT
Objective: To investigate the inhibitory effect of Tripterygium wilfordii polycoride (TWP) towards the pro-inflammatory factors (TNF-α and IL-1β) on the inflammatory reaction in macrophages induced by LPS and its regulatory effect and influence on the inflammation via TLR4/NF-kB. Methods: The MTT method was adopted to test the effect of drugs, TWP, dexamethasone (DXM) and azathioprine (AZA) on cell growth and to select the appropriate concentration. LPS was used to induce the inflammatory reaction in RAW264.7 cell line of mice. Elisa kit was adopted to test the levels of TNF-α and IL-1β. Western blotting was adopted to test the protein expression of TNF-α and IL-1β. RT-PCR was adopted to test the expression of TLR4 and NF-κB. Results: The inhibiting effect of TWP on the release of TNF-α and IL-1β in a dose dependent manner. The inhibitory effect of three different TWP dose groups is weaker than that in DXM group. However, TWP in high dose is better than AZA on TNF-α and is as strong as AZA on IL-1β. The dose dependent manner also exits in the effect on the expression of TLR4 and NF-κB, the effect is not weaker, but even stronger than that of DXM and AZA. Conclusion: The research shows that down regulation of TLR4 and NF-kB p65 may be one of the mechanisms about the TWP inhibitory effect on TNF-α and IL-1β.