Screening for impact of popular herbs improving mental abilities on the transcriptional level of brain transporters

There are a number of compounds that can modify the activity of ATP-binding cassette (ABC) and solute carrier (SLC) transporters in the blood-brain barrier (BBB). The aim of this study was to investigate the effect of natural and synthetic substances on the expression level of genes encoding transporters present in the BBB (mdr1a, mdr1b, mrp1, mrp2, oatp1a4, oatp1a5 and oatp1c1). Our results showed that verapamil caused the greatest reduction in the mRNA level while other synthetic (piracetam, phenobarbital) and natural (codeine, cyclosporine A, quercetin) substances showed a selective inhibitory effect. Moreover, extract from roots of Panax ginseng C. A. Meyer exhibited a decrease of transcription against selected transporters whereas extract from Ginkgo biloba L. leaves resulted in an increase of the expression level of tested genes except for mrp2. Extract from aerial parts of Hypericum perforatum L. was the only one to cause an increased mRNA level for mdr1 and oatp1c1. These findings suggest that herbs can play an important role in overcoming the BBB and multidrug resistance against pharmacotherapy of brain cancer and mental disorders, based on the activity of selected drug-metabolizing enzymes and transporters located in the BBB

Pharmacokinetic interaction after oral coadministration of clarithromycin and the tyrosine kinase inhibitor lapatinib in rats

Lapatinib is a tyrosine kinase inhibitor used to treat patients with locally advanced or metastatic breast cancer exhibiting overexpression of the human epidermal growth factor receptor 2 (HER2 receptor, ErbB2). Preclinical and clinical studies suggest that lapatinib is mainly metabolized by CYP3A4, therefore the study in an animal model was designed to investigate the pharmacokinetic interaction of lapatinib and clarithromycin, a well-known CYP3A4 inhibitor. The rats were subjected to one of the two study groups: lapatinib + clarithromycin (ILap+Clar; n = 6), and lapatinib + placebo (IILap; n = 6). The animals were treated with lapatinib in the oral single dose of 100 mg/kg. The antibiotic was administered orally at a dose of 25 mg/kg. Blood sampling was performed until 30 hours after dosing for pharmacokinetic assays. Plasma concentrations of lapatinib were measured by liquid chromatography-mass spectrometry. The comparison of lapatinib maximum concentration and area under the concentration-time curve in the ILap+Clar with the control group IILap gave the ratios of 1.38 (90% confidence interval (CI)) (1.14; 1.68) and 1.16 (0.75; 1.79), respectively. A statistically significant difference between analyzed groups was revealed only for maximum concentration (p = 0.0107). Single oral administration of clarithromycin significantly increased the concentration of lapatinib in rats, therefore caution should be taken during concomitant treatment with this macrolide and the tyrosine kinase inhibitor in patients

Pharmacokinetic interaction after oral coadministration of clarithromycin and the tyrosine kinase inhibitor lapatinib in rats

Lapatinib is a tyrosine kinase inhibitor used to treat patients with locally advanced or metastatic breast cancer exhibiting overexpression of the human epidermal growth factor receptor 2 (HER2 receptor, ErbB2). Preclinical and clinical studies suggest that lapatinib is mainly metabolized by CYP3A4, therefore the study in an animal model was designed to investigate the pharmacokinetic interaction of lapatinib and clarithromycin, a well-known CYP3A4 inhibitor. The rats were subjected to one of the two study groups: lapatinib + clarithromycin (ILap+Clar; n = 6), and lapatinib + placebo (IILap; n = 6). The animals were treated with lapatinib in the oral single dose of 100 mg/kg. The antibiotic was administered orally at a dose of 25 mg/kg. Blood sampling was performed until 30 hours after dosing for pharmacokinetic assays. Plasma concentrations of lapatinib were measured by liquid chromatography-mass spectrometry. The comparison of lapatinib maximum concentration and area under the concentration-time curve in the ILap+Clar with the control group IILap gave the ratios of 1.38 (90% confidence interval (CI)) (1.14; 1.68) and 1.16 (0.75; 1.79), respectively. A statistically significant difference between analyzed groups was revealed only for maximum concentration (p = 0.0107). Single oral administration of clarithromycin significantly increased the concentration of lapatinib in rats, therefore caution should be taken during concomitant treatment with this macrolide and the tyrosine kinase inhibitor in patients.This article is published as Karbownik A., Porazka J, Luczak A., Tezyk A., Grabowski T., Wolc A., Grzeskowiak E., Szalek E. 2019. Pharmacokinetic interaction after oral coadministration of clarithromycin and the tyrosine kinase inhibitor lapatinib in rats. Acta Poloniae Pharmaceutica – Drug Research 76(4): 645-651.</p

Screening for impact of popular herbs improving mental abilities on the transcriptional level of brain transporters

There are a number of compounds that can modify the activity of ABC (ATP-binding cassette) and SLC (solute carrier) transporters in the blood-brain barrier (BBB). The aim of this study was to investigate the effect of natural and synthetic substances on the expression level of genes encoding transporters present in the BBB (mdr1a, mdr1b, mrp1, mrp2, oatp1a4, oatp1a5 and oatp1c1). Our results showed that verapamil caused the greatest reduction in the mRNA level while other synthetic (piracetam, phenobarbital) and natural (codeine, cyclosporine A, quercetin) substances showed a selective inhibitory effect. Further, the extract from the roots of Panax ginseng C. A. Meyer exhibited a decrease of transcription against selected transporters whereas the extract from Ginkgo biloba L. leaves resulted in an increase of the expression level of tested genes, except for mrp2. Extract from the aerial parts of Hypericum perforatum L. was the only one to cause an increased mRNA level for mdr1 and oatp1c1. These findings suggest that herbs can play an important role in overcoming the BBB and multidrug resistance to pharmacotherapy of brain cancer and mental disorders, based on the activity of selected drug-metabolizing enzymes and transporters located in the BB