The in-vivo effect of bakumondo-to (TJ-29), a traditional Japanese medicine used for treatment of chronic airway disease, on cytochrome P450 1A2, xanthine oxidase and N-acetyltransferase 2 activity in man.

In Japan, patients with chronic airway disease are administered bakumondo-to (TJ-29), a mixture of six herbal components. We have assessed the effects of TJ-29 on the activities of cytochrome P450 (CYP) 1A2, xanthine oxidase and N-acetyltransferase 2 in 26 healthy subjects under a double-blind, randomized, placebo-controlled cross-over study design. The baseline activities of the three enzymes were assessed by the respective urinary metabolic ratios of an 8-h urine sample after an oral 150-mg dose of caffeine. Thereafter, the subjects received a thrice-daily 3.0-g dose of TJ-29 or placebo for seven days, and underwent the same caffeine test on the post-dose days 1 and 7. No statistically significant difference was observed in the activity of the three enzymes between those at baseline, and on day 1 after dosing with TJ-29 or placebo. The mean activity of CYP1A2, xanthine oxidase and N-acetyltransferase 2 tended to be lower on day 7 after dosing with TJ-29 compared with those at baseline and on day 7 after dosing with placebo. However, these changes were not statistically significant in CYP1A2 (P = 0.120), xanthine oxidase (P = 0.123) or N-acetyltransferase 2 (P = 0.056). In conclusion, TJ-29 did not appear to substantially affect the activity of CYP1A2, xanthine oxidase or N-acetyltransferase 2 in man.

Expression of flap endonuclease-1 during meiosis in a basidiomycete, Coprinus cinereus.

In the basidiomycete Coprinus cinereus (C. cinereus), which shows a highly synchronous meiotic cell cycle, the meiotic prophase I cells demonstrate flap endonuclease-1 activity. To investigate its role during meiosis, we isolated a C. cinereus cDNA homolog of flap endonuclease-1 (CcFEN-1), 1377bp in length with the open reading frame (ORF) encoding a predicted molecular mass of 51 kDa. At amino-acid residues Glu276-Pro345, a specific inserted sequence composed of 70 amino acids rich in polar forms was found to exist, without sequence identity to other eukaryotic FEN-1 or the polar amino acid rich sequences found in C. cinereus PCNA and C. cinereus DNA ligase IV, although the lengths and percentages of polar amino acids were similar. Northern hybridization analysis indicated CcFEN-1 to be expressed not only in the pre-meiotic S phase but also in meiotic prophase I. The roles of CcFEN-1 during meiosis are discussed.

High-dose rabeprazole/amoxicillin therapy as the second-line regimen after failure to eradicate H. pylori by triple therapy with the usual doses of a proton pump inhibitor, clarithromycin and amoxicillin.

BACKGROUND/AIMS: Some patients are refractory to the usual triple therapy for eradication of Helicobacter pylori, consisting of a proton pump inhibitor, amoxicillin and clarithromycin, so there needs to be an alternative strategy for retreatment after failure to eradicate the infection. METHODOLOGY: The study group comprised 17 H. pylori-positive patients who had failed to clear H. pylori infection after 1 week of treatment with usual doses of proton pump inhibitor, amoxicillin and clarithromycin. The sensitivity of H. pylori to clarithromycin and amoxicillin, and the CYP2C19 genotype status of each patient were determined and treatment with rabeprazole (10 mg qid) and amoxicillin (500 mg qid) for 2 weeks was started. RESULTS: Eleven patients were infected with a clarithromycin-resistant strain of H. pylori. Twelve patients had the homozygous extensive metabolizer genotype, 5 had the heterozygous extensive metabolizer genotype and there were none with the poor metabolizer genotype of CYP2C19. All patients were successfully cleared of their H. pylori infection without any adverse effects, irrespective of CYP2C19 genotype status (100%, 95% confidence interval: 76-100%). CONCLUSIONS: High-dose dual therapy with rabeprazole (10 mg qid) and amoxicillin (500 mg qid) for 2 weeks appears useful treatment strategy after failure of eradication of H. pylori by the usual triple proton pump inhibitor/amoxicillin/clarithromycin therapy.

The in-vivo effects of sho-saiko-to, a traditional Chinese herbal medicine, on two cytochrome P450 enzymes (1A2 and 3A) and xanthine oxidase in man.

The Chinese herbal medicine sho-saiko-to is a mixture of seven herbal components (Bupleurum root, Pinellia tuber, Scutellaria root, Jujube fruit, Ginseng root, Glycyrrhiza root and Ginger rhizome) that is widely administered to patients with chronic hepatitis in Japan. We assessed the effects of sho-saiko-to on the activity of cytochrome P450 (CYP) 1A2, CYP3A and xanthine oxidase (XO) in man. Twenty-six healthy subjects were studied to evaluate their baseline activity of CYP1A2 and XO by the respective urinary metabolic ratios of an 8-h urine sample after an oral 150-mg dose of caffeine and of CYP3A by a urinary excretion ratio of 6beta-hydroxycortisol (6beta-HC) to free cortisol (FC). Thereafter, the subjects received a twice-daily 2.5-g dose of sho-saiko-to for five days, and underwent the caffeine test on day 1 and day 5. The mean activity of CYP1A2 decreased by 16% on both day 1 and day 5 compared with the baseline (P=0.001). The mean activity of XO also significantly decreased by 25% on day 1 and 20% on day 5 (P<0.0001) compared with the baseline value. The activity of CYP3A tended to be lower on day 5 than the baseline (P=0.146). It is concluded that sho-saiko-to reduces CYP1A2 and XO activity in man.