[Effect of Huangqin Tang on the function of regulatory TLR4/MyD88 signal pathway in rats with ulcerative colitis].

This study was designed to investigate the effect of Huangqin Tang (HQT) on TLR4/Myd88 pathway and the downstream cytokines in rats with ulcerative colitis (UC) to explore its underlying mechanisms of action. The model of UC rats with cell immunoreactivity was made using a compound method (trinitrobenzene sulfonic acid plus ethanol). Rats were randomly divided into the control group, the model group, the salazosulfapyridine (SASP) group, high, medium and low dose(20, 10, 5 g·kg-1) of HQT groups. After a three-day treatment, production of NO in serum was detected by Griess assay, the levels of interleukin (IL)-4, IL-10, IL-17 and prostaglandin E2（PGE2） in serum were detected by ELISA. After a five-day treatment, the positive protein expressions of COX-2 and iNOS in the colon tissue were determined by ICH method, the protein expressions of TLR4 and MyD88 in colon tissue were determined by Western blot. Compared with the control group, the levels of NO, IL-17, PGE2, the protein expressions of TLR4, MyD88 and the protein positive expressions of COX-2, iNOS were apparently higher in the model group. Compared with model group, the above indexes were significantly improved in the SASP and high-dose HQT groups (P < 0.05). These results show that HQT has a definite effect on UC in rats. Its mechanisms of action may be achieved by inhibiting the activity of TLR4/MyD88/NF-κB signal pathway and down-regulation of NO, IL-17 and PGE2 production.

[Simultaneous determination and quantitation of anthraquinones, lignans and flavonoids in Xiao-Cheng-Qi Tang, Hou-Po-San-Wu Tang and Hou-Po-Da-Huang Tang by HPLC].

A simple and selective HPLC method for simultaneous determination and quantification of anthraquinones, lignans and flavonoids in Xiao-Cheng-Qi Tang (XCQT), Hou-Po-San-Wu Tang (HPSWT) and Hou-Po-Da-Huang Tang (HPDHT) was developed and validated. An Agilent Zorbax SB-C 18 (4.6 mm x 250 mm, 5 µm) column with the mobile phase of acetonitrile and 0.5% acetic acid aqueous solution in gradient elution mode was used. The flow rate was 1.0 mL · min(-1) at 30 °C, and injection volume was 10 µL. The detection wavelength was set at 254 nm and 294 nm simultaneously for the quantitative analysis. The current HPLC assay was validated for linearity, intra-day and inter-day precisions, accuracy, recovery and stability. The method was applied to the content comparison of the gallic acid, cinnamic acid, sennoside A, sennoside B, rhein, emodin, aloe-emodin, chrysophanol, physcion, magnolol, honokiol, narirutin, naringin, hesperidin, neohesperidin, hesperetin, naringenin and nobiletin in XCQT, HPSWT and HPDHT. The good linear equations of eighteen constituents were obtained within the investigated ranges (r > 0.998). The recovery of the method was 94.28%-99.89% and the precision was less than 5%. The sample was stable within 16 h. There were some differences between the contents of anthraquinones, lignans and flavonoids in analogous formulae about XCQT. XCQT contained the greatest abundance of anthraquinones and flavonoid, HPSWT contained the greatest abundance lignans. In conclusion, the methods are simple, low-cost, precise, accurate and reliable for the determination of eighteen constituents in analogous formulae about XCQT, and these results provide methodological support for its quality control.

[Effect of huangqin tang on the regulatory NF-κB p65 signal pathway in rats with ulcerative colitis].

To investigate the effect of huangqin tang on expression of cytokines and NF-κB p65 in rats with ulcerative colitis (UC), and to probe into its underlying mechanisms of action. The mode of UC rats with cell immunoreactivity was made using compound method (trinitrobenzene sulfonic acid and ethanol). Rats were randomly divided into control group, model group, SASP group and high dose, middle dose and low dose of huangqin tang group. The food intake, body weight and microscopic damage of rats in each group were evaluated after being treated for five days. The blood and colon tissue were also collected. Production of NO was detected by Griess assay, the expression levels of IL-6, TNF-α, PGE2 were detected by ELISA. ICH method was undertaken to determine the expression of NF-κB p65 protein in colon tissue. The food intake and body weight of model group rats were lower than that of control group. The expression levels of NO, IL-6, TNF-α, PGE2 in serum and NF-κB p65 protein of colon tissue in model group were higher than that of control group. The above indexes were ameliorated in high and middle dose of huangqin tang groups. But there was no significant difference with SASP group. NF-κB p65 may be involved in the pathogenesis of UC, and huangqin tang can inhibit the relative activity of NF-κB p65, and decrease the expression levels of NO, IL-6, TNF-α and PGE2.

[Pharmacokinetics and pharmacodynamics of huangqin tang in febrile rats].

The pharmacodynamic (PD) and pharmacokinetic (PK) properties of Huangqin Tang (HQT) were investigated in yeast-induced febrile rats. Blood sample and rectal temperature data of the rats were collected at different times after single oral administration of HQT at 20 g x kg(-1). The plasma concentrations of paeoniflorin, baicalin, wogonoside, baicalein, wogonin, oroxylin A, glycyrrhizic acid and glycyrrhetinic acid were quantified by a sensitive liquid chromatography-tandem mass spectrometric (LC-MS) method. The blood concentrations of PGE2, 1L-1ß and TNF-α were detected by radioimmunoassay (RIA). All pharmacokinetic parameters were processed by non-compartmental analysis using WinNonlin software. The potential relationship between the mean concentration of eight constituents and the antifebrile efficacy was investigated by calculating Pearson correlation coefficients. It was found that HQT had significant antifebrile efficacy in yeast-induced febrile rats, but had no effect to normal rats. The antifebrile effect of HQT can be attributed to the inhibition of PGE2, 1L-1ß and TNF-α. The constituents (baicalin, wogonoside, baicalein, wogonin, oroxylin A, glycyrrhizic acid and glycyrrhetinic acid) in febrile rats had delayed absorption and elimination, a longer residence time in the body, and higher C(max) and AUC than those in normal rats. Febrile condition could affect the pharmacokinetic behaviour of HQT in vivo; the flavonoids with the same backbone showed the similar fate in the body; baicalein and wogonin had a strong positive correlation (R > 0.66, P ≤ 0.02) with the antifebrile efficacy determined. Together, these constituents demonstrated different pharmacokinetic properties in the febrile body.