Impact of the Herbal Medicine Sophora flavescens on the Oral Pharmacokinetics of Indinavir in Rats: The Involvement of CYP3A and P-Glycoprotein

Sophora flavescens is a Chinese medicinal herb used for the treatment of gastrointestinal hemorrhage, skin diseases, pyretic stranguria and viral hepatitis. In this study the herb-drug interactions between S. flavescens and indinavir, a protease inhibitor for HIV treatment, were evaluated in rats. Concomitant oral administration of Sophora extract (0.158 g/kg or 0.63 g/kg, p.o.) and indinavir (40 mg/kg, p.o.) in rats twice a day for 7 days resulted in a dose-dependent decrease of plasma indinavir concentrations, with 55%–83% decrease in AUC0-∞ and 38%–78% reduction in Cmax. The CL (Clearance)/F (fraction of dose available in the systemic circulation) increased up to 7.4-fold in Sophora-treated rats. Oxymatrine treatment (45 mg/kg, p.o.) also decreased indinavir concentrations, while the ethyl acetate fraction of Sophora extract had no effect. Urinary indinavir (24-h) was reduced, while the fraction of indinavir in faeces was increased after Sophora treatment. Compared to the controls, multiple dosing of Sophora extract elevated both mRNA and protein levels of P-gp in the small intestine and liver. In addition, Sophora treatment increased intestinal and hepatic mRNA expression of CYP3A1, but had less effect on CYP3A2 expression. Although protein levels of CYP3A1 and CYP3A2 were not altered by Sophora treatment, hepatic CYP3A activity increased in the Sophora-treated rats. All available data demonstrated that Sophora flavescens reduced plasma indinavir concentration after multiple concomitant doses, possibly through hepatic CYP3A activity and induction of intestinal and hepatic P-gp. The animal study would be useful for predicting potential interactions between natural products and oral pharmaceutics and understanding the mechanisms prior to human studies. Results in the current study suggest that patients using indinavir might be cautioned in the use of S. flavescens extract or Sophora-derived products

An Examination of some aspects of the structure, function and synthesis of the extracellular slime produced by cystic fibrosis isolates of Pseudomonas aeruginosa in relation to the microcolony mode of growth

Bibliography: p. 150-170

Effect of <i>Sophora</i> extract on the output of urine and faeces, and on indinavir excreted via urine and faeces.

<p>(A) Urine output, (B) Faeces output, (C) Indinavir excreted in urine, (D) Indinair excreted in faeces. The urine and faeces were collected from 8 p.m. on day 6 (after the second daily treatment) to 8 p.m. on day 7 (before the second daily treatment). Values are expressed as mean ± S.E.M. (n = 8–9).</p

Effect of <i>Sophora</i> extract on the CYP3A activity in liver.

<p>The CYP3A activity was measured using a luminescent assay (P450-Glo). Bars represent mean ± S.E.M. of fold relative to the values in the control group (n = 9). Statistical significance is indicated as * <i>P</i><0.05, compared to control.</p

Pharmacokinetic parameters of indinavir (40 mg/kg orally) after multiple dosage.

<p>The rats received oral administration of indinavir (40 mg/kg) together with 1.5% Tween 80 (vehicle), <i>Sophora</i> extract (0.158 g/kg or 0.63 g/kg), Oxymatrine capsule (45 mg/kg of oxymatrine equivalent), or ethyl acetate (EA) fraction of <i>Sophora</i> extract (0.082 g/kg), twice a day for 7 days, respectively. On the experimental day (day 8), animals were pretreated with corresponding vehicle or tested drugs at 1 h prior to the last dose of indinavir given to all rats for pharmacokinetic study. Values are expressed as mean ± S.E.M. (n = 6–9). Significance is indicated as</p><p>*<i>P</i><0.05,</p><p>**<i>P</i><0.01,</p><p>***<i>P</i><0.001, compared to vehicle control.</p

Effect of <i>Sophora</i> extract on the expression of intestinal and hepatic P-gp.

<p>(A) Statistical data analysis of Western blotting results, (B) image of Western blotting results. P-gp levels were measured using the anti-rat C219 antibody as described under <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031312#s2" target="_blank"><i>Materials and Methods</i></a>. ERp29 was used as control for the normalization of P-gp density. Bars represent mean ± S.E.M. of fold relative to the values in control group (n = 7–8). Statistical significance is indicated as * <i>P</i><0.05, *** <i>P</i><0.001, compared to control.</p

Effect of <i>Sophora</i> extract on the expression of intestinal and hepatic CYP3A1 and CYP3A2.

<p>(A) Statistical data analysis of Western blotting results, (B) image of Western blotting results. CYP3A1 and CYP3A2 levels were measured respectively using the specific anti-rat CYP3A1 and CYP3A2 antibodies. ERp29 was used as control for the normalization of CYP3A density. Bars represent mean ± S.E.M. of fold relative to the values in the control group (n = 7–8). No significant difference in the expression of either intestinal or hepatic CYP3A was observed.</p

Time course of the plasma concentration of indinavir.

<p>Animals received oral administration of indinavir (40 mg/kg) together with (A) 1.5% Tween 80 (vehicle), 70% ethanol extract of <i>Sophora flavescens</i> (0.158 g/kg and 0.63 g/kg), (B) Oxymatrine capsule (45 mg/kg of oxymatrine equivalent), or ethyl acetate (EA) fraction of <i>Sophora</i> extract (0.082 g/kg), twice a day for 7 days, respectively. On the experimental day (day 8), animals were pretreated with corresponding vehicle or tested drugs at 1 h prior to the last dose of indinavir (40 mg/kg) given to all rats for pharmacokinetic study. Values are expressed as mean ± S.E.M. for each data point (n = 6–9).</p

Effect of <i>Sophora</i> extract on the intestinal and hepatic mRNA levels encoding CYP3A1, CYP3A2, mdr1a and mdr1b.

<p>(A) CYP3A1, (B) CYP3A2, (C) mdr1a, (D) mdr1b. The mRNA contents were measured by real-time PCR and calculated as comparative levels over control using the 2^−ΔΔCT method (mean ± S.E.M., n = 7–9). Statistical significance is indicated as * <i>P</i><0.05, ** <i>P</i><0.01, compared to control.</p

Vitamin D3 and carbamazepine protect against Clostridioides difficile infection in mice by restoring macrophage lysosome acidification

Clostridioides difficile infection (CDI) is a common cause of nosocomial diarrhea. TcdB is a major C. difficile exotoxin that activates macrophages to promote inflammation and epithelial damage. Lysosome impairment is a known trigger for inflammation. Herein, we hypothesize that TcdB could impair macrophage lysosomal function to mediate inflammation during CDI. Effects of TcdB on lysosomal function and the downstream pro-inflammatory SQSTM1/p62-NFKB (nuclear factor kappa B) signaling were assessed in cultured macrophages and in a murine CDI model. Protective effects of two lysosome activators (i.e., vitamin D3 and carbamazepine) were assessed. Results showed that TcdB inhibited CTNNB1/β-catenin activity to downregulate MITF (melanocyte inducing transcription factor) and its direct target genes encoding components of lysosomal membrane vacuolar-type ATPase, thereby suppressing lysosome acidification in macrophages. The resulting lysosomal dysfunction then impaired autophagic flux and activated SQSTM1-NFKB signaling to drive the expression of IL1B/IL-1β (interleukin 1 beta), IL8 and CXCL2 (chemokine (C-X-C motif) ligand 2). Restoring MITF function by enforced MITF expression or restoring lysosome acidification with 1α,25-dihydroxyvitamin D3 or carbamazepine suppressed pro-inflammatory cytokine expression in vitro. In mice, gavage with TcdB-hyperproducing C. difficile or injection of TcdB into ligated colon segments caused prominent MITF downregulation in macrophages. Vitamin D3 and carbamazepine lessened TcdB-induced lysosomal dysfunction, inflammation and histological damage. In conclusion, TcdB inhibits the CTNNB1-MITF axis to suppress lysosome acidification and activates the downstream SQSTM1-NFKB signaling in macrophages during CDI. Vitamin D3 and carbamazepine protect against CDI by restoring MITF expression and lysosomal function in mice. Abbreviations: ATP6V0B: ATPase H+ transporting V0 subunit b; ATP6V0C: ATPase H+ transporting V0 subunit c; ATP6V0E1: ATPase H+ transporting V0 subunit e1; ATP6V1H: ATPase H+ transporting V1 subunit H; CBZ: carbamazepine; CDI: C. difficile infection; CXCL: chemokine C-X-X motif ligand; IL: interleukin; LAMP1: lysosomal-associated membrane protein 1; LC3: microtubule-associated protein 1 light chain 3; LEF: lymphoid enhancer binding factor 1; MITF: melanocyte inducing transcription factor; NFKB: nuclear factor kappa B; PMA: phorbol 12-myristate 13-acetate; TcdA: Clostridial toxin A; TcdB: Clostridial toxin B; TFE3: transcription factor E3; TFEB: transcription factor EB.Published versionThis work was supported by the National Natural Science Foundation of China [82070576] and the Hong Kong Food and Health Bureau (FHB) Commissioned Health and Medical Research Fund [CID-CUHK-C]