Effect of ATP-Binding Cassette Transporters on Antipsychotics-Induced Cytotoxicity in Blood Brain Barrier Endothelial Cells

El-Zalabany, Laila; Mosad, Soad M.; Awad, Mahmoud E.; Smith, Paul A.; Elmorsy, Ekramy M.

doi:10.21608/mjfmct.2014.47661

Effect of ATP-Binding Cassette Transporters on Antipsychotics-Induced Cytotoxicity in Blood Brain Barrier Endothelial Cells

Document Type : Original Article

Authors

¹ Forensic Med. & Clin. Toxicology, Mansoura Faculty of Medicine

² Department of Forensic Medicine and Clinical Toxicology, Faculty of Medicine, Mansoura University, Egypt

³ Cellular signalling department, Biomedical Sciences School, University of Nottingham, UK

10.21608/mjfmct.2014.47661

Abstract

The ATP-binding cassette (ABC) transporters as P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) have been identified in several physiological sites. It has been suggested to play an important role in disposition of many drugs and environmental toxins. This study investigated the effects of antipsychotics (APs), including chlorpromazine (CPZ), risperidone (RIS), clozapine (CLZ), haloperidol (HAL), in their cytotoxic concentrations, on functions of P-gp and BCRP in human micro-vascular endothelial cells (HMVECs) of blood brain barrier (BBB). Firstly, the cytotoxic effects of APs were studied using alamar blue (AB) assay and inhibitory concentrations 50 (ICs50) were estimated. Presence of both P-gp and BCRP transporters was confirmed biochemically and functionally by western blotting and rhodamine-123 (Rh123) assays respectively. Verapamil and Ko134 were used as inhibitors for P-gp and BCRP transporters respectively. Lastly, the effect of transporters inhibitors verapamil (100 ∝ M) and Ko134 (10nM) on APs –induced cytotoxicity was studied. Results showed that APs were cytotoxic to the HMVECs of BBB. CPZ was the most cytotoxic. Presence of P-gp and BCRP was confirmed biochemically and functionally. In ICs50, APs showed inhibitory effect on the transporters, using Rh123 as a substrate. Also, transporters blockade increased APs-induced cytotoxicity with variable degrees. The present results suggest that a potential source of pharmacokinetic interactions exist between ABC transporters substrates and several antipsychotics in toxic conditions.

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