Planta Med 2018; 84(12/13): 895-901
DOI: 10.1055/a-0607-2743
Pharmacokinetic Investigations
Original Papers
Georg Thieme Verlag KG Stuttgart · New York

The In Vitro and In Vivo Effects of Hypoxis hemerocallidea on Indinavir Pharmacokinetics: Modulation of Efflux

Kaylee Havenga
1  Centre of Excellence for Pharmaceutical Sciences, Faculty of Health Sciences, North-West University, Potchefstroom, South Africa
,
Efrem Abay
2  Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
,
Lubbe Wiesner
2  Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory, South Africa
,
Alvaro Viljoen
3  Department of Pharmaceutical Sciences, Tshwane University of Technology, Pretoria, South Africa
4  SAMRC Herbal Drugs Research Center, Tshwane University of Technology, Pretoria, South Africa
,
Dewald Steyn
1  Centre of Excellence for Pharmaceutical Sciences, Faculty of Health Sciences, North-West University, Potchefstroom, South Africa
,
Josias Hamman
1  Centre of Excellence for Pharmaceutical Sciences, Faculty of Health Sciences, North-West University, Potchefstroom, South Africa
› Author Affiliations
Further Information

Publication History

received 26 January 2018
revised 02 April 2018

accepted 09 April 2018

Publication Date:
19 April 2018 (online)

Abstract

Hypoxis hemerocallidea (African potato) is a popular medicinal plant that has been used traditionally for the treatment of various disorders. Some HIV/AIDS patients use this traditional medicine together with their antiretroviral therapy. This study aimed to determine the impact of selected H. hemerocallidea materials (i.e., a commercial product, an aqueous extract, and biomass reference plant material) on the bidirectional permeability of indinavir across Caco-2 cell monolayers as well as the bioavailability of indinavir during an acute, single administration study in Sprague-Dawley rats. All of the selected H. hemerocallidea test materials demonstrated inhibition effects on indinavir efflux across Caco-2 cell monolayers, albeit to different extents. An increase in the bioavailability of indinavir was obtained in vivo when administered concomitantly with the H. hemerocallidea materials, albeit not statistically significantly. The change in bioavailability directly correlated with the in vitro permeability results. It can therefore be concluded that the change in permeability and bioavailability of indinavir was caused by efflux inhibition and this effect was dependent on the type of H. hemerocallidea material investigated, which was found to be in the following order: commercial product > aqueous extract > reference plant material. The clinical significance of the combined effect of efflux and metabolism inhibition by H. hemerocallidea should be determined in another in vivo model that expresses the cytochrome P450 3A4 enzyme.

Supporting Information