Preparation of tanshinone Ⅱ_A-glycyrrhetinic acid solid lipid nanoparticles and its inhibitory effect on acne / 中国中药杂志

The optimal prescription of tanshinone Ⅱ_A(TSN)-glycyrrhetinic acid(GA) solid lipid nanoparticles(GT-SLNs) was explored and evaluated in vivo and in vitro, and its effect on acne after oral administration was investigated. The preparation processing and prescription were optimized and verified by single factor and response surface methodology. The in vitro release of GA and TSN in GT-SLNs was determined by ultra-performance liquid chromatography(UPLC). The effect of GT-SLNs on acne was investigated by the levels of sex hormones in mice, ear swelling model, and tissue changes in sebaceous glands, and the pharmacokinetics was evaluated. The 24-hour cumulative release rates of GA and TSN in SLNs were 65.87%±5.63% and 36.13%±2.31% respectively. After oral administration of GT-SLNs and the mixture of GA and TSN(GT-Mix), the AUC_(0-t) and AUC_(0-∞) of TSN in GT-SLNs were 1.98 times and 4.77 times those in the GT-Mix group, respectively, and the peak concentration of TSN in the GT-SLNs group was 17.2 times that in the GT-Mix group. After intragastric administration of GT-SLNs, the serum levels of testosterone(T) and the ratio of testosterone to estradiol(T/E2) in the GT-SLNs group significantly declined, and the sebaceous glands of mice were atrophied to a certain extent. The results demonstrated that obtained GT-SLNs with good encapsulation efficiency and uniform particle size could promote the release of GA and TSN. GT-SLNs displayed therapeutic efficacy on acne manifested by androgen increase, abnormal sebaceous gland secretion, and inflammatory damage.

Effect of Connexin43 on Mechanical Tension-stimulated Osteogenic Transcription Factors of Human Periodontal Ligament Fibroblasts / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the expression and effect of Connexin43 (Cx43) on tensile tension-stimulated osteogenic transcription factors of human periodontal ligament fibroblasts (hPDLFs).</p><p><b>METHODS</b>After hPDLFs were treated with 5% elongation tension for 1 h, 2 h, 4 h, 8 h, and 24 h, we examined the expressions of Cx43, Osterix, and RUNX2 at the mRNA level. After Cx43 expression was suppressed by siRNA or 18α-GA, the changes The mRNA in hPDLFs of Osterix and RUNX2 were observed.</p><p><b>RESULTS</b>The expressions of Cx43, Osterix, and RUNX2 mRNA in hPDLFs increased in a time-dependent fashion following tensile strain (all P<0.05), with the highest level at 5% elongation for 24 h. After Cx43 expression was blocked by two different methods, the increasing expressions of Osterix and RUNX2 were inhibited.</p><p><b>CONCLUSIONS</b>5% cyclic tension upregulates Cx43 expression and promotes the expression of Osterix and RUNX2 in a time-dependent manner. Cx43 may be involved in the osteogenic response of hPDLFs to mechanical tension.</p>

Destabilizing effect of glycyrrhetinic acid on pre-formed biofilms of Streptococcus mutans / 대한구강보건학회지

OBJECTIVES: In this study, the destabilizing effect of glycyrrhetinic acid on pre-formed biofilms of Streptococcus mutans (S. mutans) was observed. METHODS: Alamar blue assay was used to determine the toxicity of glycyrrhetinic acid on pre-formed biofilms of S. mutans. Four different concentrations (0, 3.75, 7.5, 15 µg/ml) of glycyrrhetinic acid were tested. Changes in the biofilm architecture after exposure to glycyrrhetinic acid were analyzed by scanning electron microscopy (SEM). Moreover, the role of glycyrrhetinic acid in enhancing the antimicrobial activity of cetylpyridinium chloride (CPC), an antimicrobial agent commonly used in oral health care products, was evaluated. RESULTS: Glycyrrhetinic acid concentration of up to 15 µg/ml had little cytotoxic effect but significantly changed the biofilm architecture. SEM analysis revealed destabilized biofilm structure after the preformed biofilms were exposed to glycyrrhetinic acid. Supplementing 2.5 µg/ml CPC with 15 µg/ml glycyrrhetinic acid significantly enhanced the bactericidal effect of CPC on the pre-formed biofilms than that in the non-supplemented CPC treated control. This indicates that glycyrrhetinic acid enhanced the antimicrobial activity of CPC by modifying the structure, thus facilitating the penetration of CPC into the biofilm. CONCLUSIONS: Glycyrrhetinic acid could be a potential agent to effectively control S. mutans biofilms responsible for dental caries.

Effect of 18-β Glycyrrhetinic Acid on the Endoplasmic Reticulum of Nasal Epithelial Cells in Allergic Rhinitis Model Rats / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the effect of 18-β glycyrrhetinic acid (GA) on the endoplasmic reticulum of nasal epithelial cells in allergic rhinitis (AR) model rats.</p><p><b>METHODS</b>Totally 96 Wistar rats were randomly divided into the blank group, the AR model group, the loratadine group, the GA group, 24 in each group. AR models were established by peritoneally injecting ovalbumin (OVA). Morphological scoring was performed. GA at 21. 6 mg/kg was intragastrically administered to rats in the GA group. Nasal mucosal tissues were taken for electron microscopic examinations at the second, fourth, sixth, and tenth week after drug intervention.</p><p><b>RESULTS</b>The overlapping score was 2.10 ± 0.45 in the blank group, 5.10 ± 0.56 in the loratadine group, 5.10 ± 0.56 in the AR model group, 5.20 ± 0.78 in the GA group, showing statistical difference when compared with the blank group (P < 0.01). Results under transmission electron microscope showed that the number of the endoplasmic reticulum increased in the AR model group, with obvious cystic dilatation, a lot of vacuole formation, and degranulation. A large number of free ribosomes could be seen in cytoplasm. With persistent allergen exposure, changes mentioned above was progressively aggravated in the endoplasmic reticulum of nasal mucosal epithelium in the AR model group. But the dilation of endoplasmic reticulum, vacuole formation, and degranulation were relieved in the GA group, and got close to those of the blank group.</p><p><b>CONCLUSION</b>18-β GA could improve the expansion, vacuolization, and degranulation of the endoplasmic reticulum of nasal epithelial cells in AR model rats.</p>

Design, synthesis and antiproliferative activity in cancer cells of novel 18β-glycyrrhetinic acid derivatives / 药学学报

To investigate the anticancer effects of ring C in 18β-glycyrrhetinic acid (GA), a series of GA derivatives featured with 9(11)-ene moiety in ring C were designed and synthesized. The structures were confirmed by IR, LC-MS and 1H NMR. Their inhibitory effects towards human prostate cancer PC-3 and leukemia HL-60 cell lines were determined. Most of the derivatives displayed stronger antiproliferative activities than GA. Particularly, compound 14 showed promising anticancer activity with the GI50 values of 4.48 µmol · L(-1) and 1.2 µmol · L(-1) against PC-3 and HL-60 cells respectively, which is worth further study.

Microbial transformation of glycyrrhetinic acid by Cunninghamella blakesleeana / 中国中药杂志

A study on the microbial transformation of glycyrrhetinic acid (GA) was conducted by a fungus, Cunninghamella blakesleeana CGMCC 3.970 systematically. After incubation with the cell cultures of C. blakesleeana CGMCC 3.970 at 25 degrees C for 7 days on a rotary shaker operating at 135 r x min(-1), GA was converted into one major product and five minor products. The products were extracted and purified by solvent extraction, macroporous adsorbent resin, silica gel column chromatography, and semi-preparative RP-HPLC chromatography. Their structures were identified as 3-oxo-15α-hydroxy-18β-glycyrrhetinic acid(1), 3-oxo-15β-hydroxy-18β-glycyrrhetinic acid (2), 7β,15α-dihydroxy-18β-glycyrrhetinic acid (3), 3-oxo-7β, 15α-dihydroxy-18β-glycyrrhetinic acid (4), 7β-hydroxy-18β-glycyrrhetinic acid(5) and 15α-hydroxy-18β-glycyrrhetinic acid(6) by the analyses of MS, 1H-NMR and 13C-NMR spectroscopic data respectively. Among them, 2 was a new compound. These results suggest that C. blakesleeana CGMCC 3.970 has the capability of selective ketonization and hydroxylation for GA. [Key words] glycyrrhetinic acid; Cunninghamella blakesleeana CGMCC 3. 970; microbial transformation

The effect of 18β-sodium glycyrrhetinic acid on the nasal mucosa epithelial cilia in rat models of allergic rhinitis / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate 18β-sodium glycyrrhetinic acid impact on nasal mucosa epithelial cilia in rat models of allergic rhinitis (AR).@*METHOD@#AR models were established by ovalbumin-induction. Wister rats were randomly divided into groups as normal group, model group, budesonide (0.2 mg/kg) group and sodium glycyrrhetinic acid (20 mg/kg and 40 mg/kg) group after the success of AR models. At 2 weeks and 4 weeks after treatment, the behavioral changes of rats were observed and recorded, and nasal septum mucosae were collected after 2 week and 4 week intervention, and the morphological changes of nasal mucosae were observed by electron microscope.@*RESULT@#Model group developed typical AR symptoms, the total score in all animals was > 5. With budesonide and sodium glycyrrhetinic acid treatment, the AR symptoms were relieved, and the total scores were reduced significantly (P < 0.01). Compared with the model group: after 2 weeks' intervention, thick mucous secretions on the top of columnar epithelium cilia in rat nasal mucosa was significantly reduced, and cilia adhesion, lodging, shedding were relieved in budesonide group and sodium glycyrrhetinic acid group, the relieve in budesonide group was slightly better than that in sodium glycyrrhetinic acid group; after 4 week intervention, Cilia adhesion, lodging, shedding were completely vanished, and the cilia were ranged in regular direction in budesonide group and sodium glycyrrhetinic acid group. Cilia in sodium glycyrrhetinic acid (20 mg/kg) group was more orderly, smooth than that in budesonide group and sodium glycyrrhetinic acid group (40 mg/kg), and the condition of cilia in sodium glycyrrhetinic acid group (20 mg/kg) was similar to the normal group.@*CONCLUSION@#18β-sodium glycyrrhetinic acid is effective to restrain the pathological changes of nasal mucosa cilia in rat models of AR.

Improved anti-tumor activity and safety profile of a paclitaxel-loaded glycyrrhetinic acid-graft-hyaluronic acid conjugate as a synergistically targeted drug delivery system / 中国天然药物

The present study was designed to develop and evaluate glycyrrhetinic acid-graft-hyaluronic acid (HGA) conjugate for intravenous paclitaxel (PTX) delivery. Lyophilized PTX-loaded self-assembled HGA nanoparticles (PTX/HGAs) were prepared and characterized by dynamic light scattering measurements. Hemolysis test, intravenous irritation assessment, and in vitro and in vivo pharmacodynamic studies were carried out. B16F10 and HepG2 cells were used in the cell apoptosis analysis. The mouse MDA-MB-231 xenograft model was used for the evaluation of in vivo anticancer activity of the drugs, by the analysis of tumor growth and side effects on other tissues. PTX/HGAs showed high stability and good biocompability. Compared with PTX plus GA plus HA solution, PTX/HGAs displayed obvious superiority in inducing the apoptosis of the cancer cells. Following systemic administration, PTX/HGAs efficiently suppressed tumor growth, with mean tumor inhibition ratio (TIR) being 65.08%, which was significantly higher than that of PTX plus GA plus HA treatment. In conclusion, PTX/HGAs demonstrated inhibitory effects tumor growth without unwanted side effects, suggesting that HGA conjugates hold a great potential as a delivery carrier for cancer chemotherapeutics to improve therapeutic efficacy and minimize adverse effects.

Comparison of Ocular Biometry Using Low-Coherence Reflectometry with Other Devices for Intraocular Lens Power Calculation

PURPOSE: To compare axial length (AL) and keratometry (K) using optical low-coherence reflectometry (OLCR, Lenstar LS900(R), Haag-Streit, Bern, Switzerland) with current ocular biometry devices and evaluate the accuracy of intraocular lens (IOL) power calculation. METHODS: In this prospective, comparative observational study of eyes with cataracts, AL and K were measured using an OLCR device (Lenstar LS900(R), Haag-Streit), partial coherence interferometry (PCI, IOL Master(R), Carl Zeiss, Jena, Germany), A-scan (Eyecubed) and automated keratometry (KR-7100, Topcon, Tokyo, Japan). IOL power calculation was performed using the Sanders-Retzlaff-Kraff (SRK/T) formula. The IOL prediction error (PE) was calculated by subtracting the predicted IOL power from the postoperative (PO) IOL power (PO 4 weeks, PO 12 weeks). RESULTS: A total of 50 eyes of 39 patients with cataracts (mean age 67.12 +/- 8.51 years) were evaluated in this study. AL and K were not significantly different between the OLCR device and other devices (analysis of variance [ANOVA], p = 0.946, 0.062, respectively). The mean PE in IOL power calculation was -0.22 +/- 0.50D with the OLCR device, 0.08 +/- 0.45D with the PCI device and -0.01 +/- 0.48D with A-scan and automated keratometry (ANOVA, p = 0.006). The highest percentage of eyes with PE smaller than +/- 0.5D was IOL Master(R) followed by Eyecubed and then Lenstar LS900(R). The mean absolute PE was not statistically significant among the 3 devices (ANOVA, p = 0.684). CONCLUSIONS: Ocular biometry measurements were comparable between the OLCR device and the PCI ultrasound device. However, the IOL power prediction showed significant differences among the 3 devices. Therefore, the differences in application of these devices should be considered.

Laminaria japonica increases plasma exposure of glycyrrhetinic acid following oral administration of Liquorice extract in rats / 中国天然药物

The present study was designed to investigate the effects of Laminaria japonica (Laminaria) on pharmacokinetics of glycyrrhetinic acid (GA) following oral administration of Liquorice extract in rats. Following oral administrations of single-dose and multi-dose Liquorice extract and Liquorice-Laminaria extract, respectively, plasma samples were obtained at various times and the concentrations of GA, liquiritigenin, and isoliquiritigenin were measured by LC-MS. The effects of Laminaria extract on pharmacokinetics of GA were also investigated, following single-dose and multidose of glycyrrhizic acid (GL). The effects of Laminaria extract on intestinal absorption of GA and GL were studied using the in situ single-pass intestinal perfusion model. The metabolism of GL to GA in the contents of small and large intestines was also studied. The results showed Liquorice-Laminaria extract markedly increased the plasma concentration of GA, accompanied by a shorter Tmax. Similar alteration was observed following multidose administration. However, pharmacokinetics of neither liquiritigenin nor isoliquiritigenin was affected by Laminaria. Similarly, Laminaria markedly increased concentration and decreased Tmax of GA following oral GL were observed. The data from the intestinal perfusion model showed that Laminaria markedly increased GL absorption in duodenum and jejunum, but did not affect the intestinal absorption of GA. It was found that Laminaria enhanced the metabolism of GL to GA in large intestine. In conclusion, Laminaria increased plasma exposures of GA following oral administration of liquorice or GL, which partly resulted from increased intestinal absorption of GL and metabolism of GL to GA in large intestine.

Efficacy and safety of Stronger Neo-Minophagen C for treatment of chronic hepatitis B: a meta-analysis of randomized controlled trials / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the efficacy and safety of Stronger Neo-Minophagen C (SNMC) in the treatment of chronic hepatitis B.</p><p><b>METHODS</b>We searched MEDLINE, EMBASE, CBM, and CNKI up to December, 2012 to identify randomized controlled trials (RCTs) comparing Stronger Neo-Minophagen C plus other therapy versus others therapy for chronic hepatitis B. Two reviewers independently assessed the risk of bias and extracted data from the included RCTs according to the Cochrane Reviewers Handbook 5.1.0. Meta-analyses were performed using RevMan 5.1 software.</p><p><b>RESULTS</b>Thirty-one trials involving 2753 patients were included in the analysis. The results of meta-analyses showed that SNMC improved hepatic functions of the patients by reducing ALT (MD=-31.63, 95% CI: -51.57, -11.70), AST (MD=-18.70, 95% CI:-25.10, -12.30), TBIL (MD=-12.17, 95% CI: -17.63,-6.71), HA (MD=-94.89, 95% CI: -125.19, -64.60), LN (MD=-40.08, 95% CI: -52.38,-27.78), IV-C (MD=-50.61, 95% CI:-63.40, -37.81), PC-III (MD=-49.71, 95% CI: -71.72, -27.69) as compared with the control group. The seroconversion rate of HBeAg (OR=2.23, 95% CI: 1.70, 2.94), HBV-DNA (OR=2.20, 95% CI: 1.70, 2.84), HBsAg (OR=2.25, 95% CI: 1.24 , 4.07), total response rate (OR=4.37, 95% CI: 2.62, 7.28), and ALT normalization rate (OR=3.77, 95% CI: 2.46, 5.79) were all significantly higher in the combined therapy group than in the control group.</p><p><b>CONCLUSION</b>SNMC plus other therapy is more effective than other therapy alone in improving the hepatic function and hepatic fibrosis and increasing hepatic seroconversion rate in patients with chronic hepatitis B without causing serious adverse events. But considering the low quality of the included studies, the results should be interpreted with caution and awaits further confirmation by high-quality, large-scale RCTs.</p>

Inhibitory effect of 18β-glycyrrhetinic acid on KCl- and PE-induced constriction of rat renal interlobar artery in vitro / 生理学报

The aim of the present study is to investigate the effect of 18β-glycyrrhetinic acid (18β-GA) on KCl- and PE-induced constriction of rat renal interlobar artery (RIA). Pressure myograph system was used to observe the constriction induced by KCl and PE (endothelial independent vasoconstrictor) in acutely separated RIA of Wistar rats with or without 18β-GA pretreatment. Whole-cell patch clamp recordings were used to observe the effect of 18β-GA on membrane input capacitance (C(input)), membrane input conductance (G(input)) or membrane input resistance (R(input)) of smooth muscle cells embedded in arteriole segment. The results showed that both KCl (30-100 mmol/L) and PE (0.1-30 μmol/L) induced contraction of RIA in a concentration-dependent way. After pretreatment with 18β-GA (100 μmol/L), KCl- or PE-induced constriction of RIA was significantly decreased. After application of 18β-GA (100 μmol/L), the C(input), G(input) and R(input) of the in situ smooth muscle cells were very close to those of dispersed single smooth muscle cells. These results suggest 18β-GA inhibits the contraction induced by KCl and PE, and the underlying mechanism may involve the inhibitory effect of 18β-GA on gap junction.

The effect of 18β-glycyrrhetinic acid on tight junctions of the nasal mucosa epithelial cells in rat models with allergic rhinitis / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To observe 18β-glycyrrhetinic acid (GA) impact on ultrastructure of tight junctions (TJs) of nasal mucosa epithelial cells in rats models of allergic rhinitis (AR).@*METHOD@#Ninety-six Wistar rats were randomly divided into control group, model group, loratadine group, and 18β-glycyrrhetinic acid group, and each group had 24 rats. Ovalbumin was used to establish a rat AR model. The behavioral changes and the tight junctions of nasal epithelial were observed and compared in different groups after 2,4,6 and 10 weeks intervention.@*RESULT@#The length of TJs in allergic rhinitis model became shorter, electron-high-density plasma membrane became thicker, number of the integration loci reduced and gap of TJs widened or even ruptured. With the consistent effect of allergens,the changes of TJs in the model group aggravated gradually,and the changes of ultrastructure of TJs in 18β-glycyrrhetinic acid group was relieved apparently compared to model group and even were close to the control model with time.@*CONCLUSION@#18β-glycyrrhetinic acid can recover the ultrastructure of the tight junctions of AR rat nasal epithelial cells.

Anti-carcinogenic effects of non-polar components containing licochalcone A in roasted licorice root

BACKGROUND/OBJECTIVE: Licorice has been shown to possess cancer chemopreventive effects. However, glycyrrhizin, a major component in licorice, was found to interfere with steroid metabolism and cause edema and hypertension. The roasting process of licorice modifies the chemical composition and converts glycyrrhizin to glycyrrhetinic acid. The purpose of this study was to examine the anti-carcinogenic effects of the ethanol extract of roasted licorice (EERL) and to identify the active compound in EERL. MATERIALS/METHODS: Ethanol and aqueous extracts of roasted and un-roasted licorice were prepared. The active fraction was separated from the methylene chloride (MC)-soluble fraction of EERL and the structure of the purified compound was determined by nuclear magnetic resonance spectroscopy. The anti-carcinogenic effects of licorice extracts and licochalcone A was evaluated using a MTT assay, Western blot, flow cytometry, and two-stage skin carcinogenesis model. RESULTS: EERL was determined to be more potent and efficacious than the ethanol extract of un-roasted licorice in inhibiting the growth of DU145 and MLL prostate cancer cells, as well as HT-29 colon cancer cells. The aqueous extracts of un-roasted and roasted licorice showed minimal effects on cell growth. EERL potently inhibited growth of MCF-7 and MDA-MB-231 breast, B16-F10 melanoma, and A375 and A2058 skin cancer cells, whereas EERL slightly stimulated the growth of normal IEC-6 intestinal epithelial cells and CCD118SK fibroblasts. The MC-soluble fraction was more efficacious than EERL in inhibiting DU145 cell growth. Licochalcone A was isolated from the MC fraction and identified as the active compound of EERL. Both EERL and licochalcone A induced apoptosis of DU145 cells. EERL potently inhibited chemically-induced skin papilloma formation in mice. CONCLUSIONS: Non-polar compounds in EERL exert potent anti-carcinogenic effects, and that roasted rather than un-roasted licorice should be favored as a cancer preventive agent, whether being used as an additive to food or medicine preparations.

Effect of induced diabetes mellius on the histological structure of the renal cortex of adult male albino rats and the possible protective role of licorice extract

Diabetes is one of the most common chronic metabolic disorders worldwide. One of the major complications of type 2 diabetes is diabetic nephropathy. The present study was to investigate the effect of type 2 diabetes on the histological structure of the renal cortex of adult male albino rats and the role of licorice ethanolic extract on diabetic renal affection. Forty adult male albino rats were utilized. They were classified into three main groups: the control group [group I], the experimental diabetic group [group II], and the possible protected group [group III]. Type 2 diabetes was induced in rats in groups II and III by giving them a high-fat diet and a single low dose of streptozotocin. Diabetic rats were divided into two subgroups: untreated subgroup IIa and treated subgroup IIb. The possible protected group received licorice ethanolic extract concomitant with the high-fat diet and the single low dose of streptozotocin. At the end of the experiment, the kidneys were dissected out and processed for light and electron microscopic examination. Fasting blood glucose level, fasting insulin level, serum urea, and creatinine were estimated and statistically analyzed. Examination of the renal cortex of untreated diabetic subgroup IIa demonstrated glomerulosclerosis and distorted podocyte foot processes. The cells lining convoluted tubules revealed thick basement membranes, disorganization of basal infoldings, and mitochondrial disarrangement. The area% of positive Bax immunoreaction was significantly increased in subgroup IIa as compared with subgroup IIb and group III. Examination of the renal cortex of the treated diabetic animals [subgroup IIb] revealed little improvement and failure of licorice extract to normalize renal cortical changes, most probably due to late intervention. In contrast, the protected group [group III] revealed a nearly preserved normal architecture. Changes in the renal cortical structure were attenuated with prophylactic therapy of licorice ethanolic extract

LC-MS quantification and pharmacokinetics of the multi-constituents of Huangqin Tang in rat plasma after different single oral doses / 药学学报

The current study aims to investigate the pharmacokinetic properties of Huangqin Tang on different oral doses. An LC-MS method for simultaneous determination of flavonoids and terpenoids in rat plasma was developed and validated. Plasma samples were treated with hydrochloric acid (containing 1% ascorbic acid), precipitated with acetonitrile, separated on a Zorbax SB-C18 column, detected by single quadruple mass spectrometry with an electrospray ionization interface, and quantified using selected ion monitoring mode. All pharmacokinetic parameters were processed by non-compartmental analysis using WinNonlin software. The results of specificity, linearity, intra-day and inter-day precisions, accuracy, and stability for LC-MS assay were suitable for the quantification of paeoniflorin, baicalin, wogonoside, baicalein, wogonin, oroxylin A, glycyrrhizic acid and glycyrrhetinic acid in rat plasma. The concentration-time profiles of baicalin, wogonoside, baicalein, wogonin, oroxylin A and glycyrrhizic acid showed double-peak phenomenon after Huangqin Tang was orally administered at 40 g x kg(-1) dose; all eight constituents in rat plasma showed good dose-exposure relationship within the dosage of 10-40 g x kg(-1); although plasma concentrations were different, the flavonoids with the same backbone showed the similar fate in the body with the corresponding dosage. In conclusion, the LC-MS assay was successfully applied for the pharmacokinetic study of multi-constituents of Huangqin Tang with different doses. Additionally, these constituents demonstrated good pharmacokinetic properties in the body.

In vivo effect of triptolide combined with glycyrrhetinic acid on rat cytochrome P450 enzymes / 药学学报

Triptolide (TP) is a major active component in Tripterygium root, but its therapeutic window was very narrow due to its severe multi-organ toxicity. In this work, the effect of TP combined with glycyrrhetic acid (GA) on mRNA expression and activity of four cytochrome P450 (CYP) enzymes in rat liver was studied after intragastric administration of TP (0.05, 0.3 and 0.6 mg x kg(-1) x day(-1)) and TP (0.6 mg x kg(-1) x day(-1)) combined with GA (30 mg x kg(-1) x day(-1)) for 7 consecutive days. Compared with the control, the high dose of TP significantly up-regulated the mRNA expression levels of CYP2E1, 1A2, 3A1 and 2C11, the co-administration of TP and GA further up-regulated the mRNA expression levels of CYP3A1, 2C11 and 2E1 as compared with the high dose of TP. Meanwhile, TP at high dose and combined with GA significantly increased CYP3A-associated testosterone 6beta-hydroxylation activity (2.2-fold and 4.1-fold, respectively) as compared with the control. Because TP is mainly metabolized by CYP3A2 in male rats, the present work indicated that TP-induced increase of CYP3A activity might be an important reason for the rapidly metabolic clearance of TP in rat liver, and GA can reduce the hepatotoxicity of TP by promoting its hepatic metabolic clearance. Furthermore, the results also suggest that the drug interactions might be occurred when TP and GA were co-administered with other CYP3A substrate drug.

The effect of 18beta-glycyrrhetinic acid on gap junction among cerebral arteriolar smooth muscle cells in Wistar rat and spontaneously hypertensive rat / 中国应用生理学杂志

<p><b>OBJECTIVE</b>This study compared Wistar rat with spontaneously hypertensive rat (SHR) on the electrophysiology and coupling force of the smooth muscle cells in the cerebral arteriolar segments and observe the influence of 18beta-glycyrrhetinic acid(18beta-GA) on the gap junctions between the arterial smooth muscle cells.</p><p><b>METHODS</b>The outer layer's connective tissue of the cerebral arteriolar segments was removed. Whole-cell patch clamp recordings were used to observe the 18beta-GA's impaction on the arteriolar segment membrane's input capacitance (C(input)), input conductance (G(input)) and input resistance (R(input)) of the smooth muscle cells.</p><p><b>RESULTS</b>(1) The C(input) and G(input) of the SHR arteriolar segment smooth muscle cells was much higher than the Wistar rats, there was significant difference (P < 0.05). (2) 18beta-GA concentration-dependently reduced C(input) and G(input) (or increase R(input)) on smooth muscle cells in arteriolar segment. IC50 of 18beta-GA suppression's G(input) of the Wistar rat and SHR were 1.7 and 2.0 micromol/L respectively, there was not significant difference (P > 0.05). After application of 18beta-GA concentration > or = 100 micrmol/L, the C(input), G(input) and R(input) of the single smooth muscle cells was very close.</p><p><b>CONCLUSION</b>Gap junctional coupling is enhanced in the SHR cerebral arterial smooth muscle cells. 18beta-GA concentration-dependent inhibits Wistar rat's and SHR cerebral arteriolar gap junctions between arterial smooth muscle cells. The inhibitory potency is similar between the two different rats. When 18beta-GA concentration is > or = 100 micromol/L, it can completely block gap junctions between arteriolar smooth muscle cells.</p>

Effect of Puromycin Aminonucleoside on Podocyte P-Cadherin

PURPOSE: To test whether the expression of P-cadherin, a component of slit diaphragms between podocyte foot processes, would be altered by puromycin aminonucleoside (PAN) in a cultured podocyte in vitro. METHODS: Rat glomerular epithelial cells (GEpC) were cultured with various concentrations of PAN. The distribution of P-cadherin was examined with a confocal microscope. Western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR) were used to measure the change in P-cadherin expression. RESULTS: This study found that P-cadherin was concentrated in the inner and peripheral cytoplasm with high concentrations of PAN under immunofluorescence views. Western blotting of GEpC revealed that PAN induced a decrease of P-cadherin in dose- and time-dependent manners. A high dose (50 microg/mL) of PAN decreased P-cadherin expression by 21.9% at 24 h (P<0.05) and 31.9% at 48 h (P<0.01) compared to those without PAN. In RT-PCR, high concentrations (50 microg/mL) of PAN also decreased P-cadherin mRNA expression, similar to protein suppression, by 23.5% at 48 h (P<0.05). CONCLUSION: Podocytes exposed to PAN in vitro concentrated P-cadherin internally, and reduced P-cadherin mRNA and protein expression. This could explain the development of proteinuria in experimental PAN-induced nephropathy.

Effect of oral administration of glycyrrhetinic acid on six metal elements in rat serum / 中国中药杂志

<p><b>OBJECTIVE</b>To determine glycyrrhetinic acid concentration in rat plasma and concentration of calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg) and sodium (Na) in rat serum after oral administration by LC-MS/MS and the flame atomic absorption method, and analyze the effect of glycyrrhetinic acid on the six elements in serum.</p><p><b>RESULT</b>A similar variation trend between the concentration of glycyrrhetinic acid in plasma and that of Na, Cu elements in serum after oral administration of glycyrrhetinic acid was observed. Glycyrrhetinic acid in plasma at 2 h after administration reached the peak. Meanwhile, the concentration of Na and Cu at 4 h after the administration of glycyrrhetinic acid exhibited a significant increase (P < 0.05). Moreover, an increasing glycyrrhetinic acid dosage could result in the accumulation of Cu and Na in rat serum. Compared with the control group, the concentration of Cu and Na in the the glycyrrhetinic acid administration group with doses of 200 and 400 mg x kg(-1) revealed a significant increase (P < 0.05). However, glycyrrhetinic acid did not exhibit the great impact on the concentration of other elements in serum.</p><p><b>CONCLUSION</b>This study focuses on the effect of oral administration of glycyrrhetinic acid on six metal elements in rat serum and provides an experimental basis for the adverse effect of glycyrrhetinic acid in clinical-applications.</p>