Inhibitory Effect of AB-PINACA, Indazole Carboxamide Synthetic Cannabinoid, on Human Major Drug-Metabolizing Enzymes and Transporters

Abstract

Indazole carboxamide synthetic cannabinoid, AB-PINACA, has been placed into Schedule I of the Controlled Substances Act by the US Drug Enforcement Administration since 2015. Despite the possibility of AB-PINACA exposure in drug abusers, the interactions between AB-PINACA and drug-metabolizing enzymes and transporters that play crucial roles in the pharmacokinetics and efficacy of various substrate drugs have not been investigated. This study was performed to investigate the inhibitory effects of AB-PINACA on eight clinically important human major cytochrome P450s (CYPs) and six uridine 5′-diphospho-glucuronosyltransferases (UGT) in human liver microsomes and the activities of six solute carrier transporters and two efflux transporters in transporter-overexpressing cells. AB-PINACA reversibly inhibited the metabolic activities of CYP2C8 (Ki, 16.9 µM), CYP2C9 (Ki, 6.7 µM), and CYP2C19 (Ki, 16.1 µM) and the transport activity of OAT3 (Ki, 8.3 µM). It exhibited time-dependent inhibition on CYP3A4 (Ki, 17.6 µM; kinact, 0.04047 min−1). Other metabolizing enzymes and transporters such as CYP1A2, CYP2A6, CYP2B6, CYP2D6, UGT1A1, UGT1A3, UGT1A4, UGT1A6, UGT1A9, UGT2B7, OAT1, OATP1B1, OATP1B3, OCT1, OCT2, P-glycoprotein, and BCRP, exhibited only weak interactions with AB-PINACA. These data suggest that AB-PINACA can cause drug-drug interactions with CYP3A4 substrates but that the significance of drug interactions between AB-PINACA and CYP2C8, CYP2C9, CYP2C19, or OAT3 substrates should be interpreted carefully.

Involvement of Organic Anion Transporters in the Pharmacokinetics and Drug Interaction of Rosmarinic Acid

“…The percentages of inhibition were calculated by the ratio of the amounts of rosmarinic acid in the presence and absence of the inhibitors, and the transporter-mediated uptake rate ( ν ) of probe substrate versus concentrations of inhibitors (I) were fitted to an inhibitory effect equation [ν = E max (1 − [I]/IC 50 + [I])] using WinNonlin [ 30 , 31 ]. E max indicated the maximum effect and IC 50 represented the half-maximal inhibitory concentration.…”

Tetrahydrofurofuranoid Lignans, Eudesmin, Fargesin, Epimagnolin A, Magnolin, and Yangambin Inhibit UDP-Glucuronosyltransferase 1A1 and 1A3 Activities in Human Liver Microsomes

“…The inhibitory potentials of eudesmin, fargesin, epimagnolin A, magnolin, and yangambin on six UGT activities were measured as described previously [ 31 ]. Briefly, reaction mixture (100 µL) containing 50 mM Tris buffer (pH 7.4), 10 mM MgCl 2 , 25 µg/mL alamethicin, 5 mM UDPGA, ultrapooled human liver microsomes (0.2 mg/mL), various concentrations of eudesmin, fargesin, epimagnolin A, magnolin, or yangambin in acetonitrile (final concentrations of 0.1, 1, 10, 20, 50, 100, and 200 µM each, acetonitrile less than 1% ( v / v ), and the UGT probe cocktails of set A (0.5 µM SN-38 for UGT1A1, 2 µM chenodeoxycholic acid for UGT1A3, and 0.5 µM trifluoperazine for UGT1A4) or set B (1 µM N -acetylserotonin for UGT1A6, 0.2 µM mycophenolic acid for UGT1A9, and 1 µM naloxone for UGT2B7) were incubated at 37 °C for 60 min.…”

“…UGT metabolites were simultaneously quantified using Agilent 6495 triple quadrupole mass spectrometer equipped with Agilent 1290 Infinity UPLC (Agilent Technologies, Wilmington, DE, USA) as described previously [ 31 ]. Analytes were eluted from an Atlantis dC18 column (3 µm, 2.1 mm internal diameter × 100 mm, Waters Co., Milford, MA, USA) by the gradient elution of mobile phase A (5% acetonitrile in 0.1% formic acid) and mobile phase B (95% acetonitrile in 0.1% formic acid) at flow rate of 0.3 mL/min.…”

“…IC 50 values (i.e., the inhibitor concentrations required for 50% inhibition of the control activity) of eudesmin, fargesin, epimagnolin A, magnolin, and yangambin on UGT activities were estimated using SigmaPlot (version 12.0; Systat Software, San Jose, CA, USA). The apparent kinetic inhibition constant ( K i ) values of eudesmin, fargesin, epimagnolin A, magnolin, and yangambin and the mode of inhibition were calculated from Dixon plot transformation [ 31 ].…”

“…Pharmaceutics 2021, 13, 5 of 14 magnolin, and yangambin and the mode of inhibition were calculated from Dixon plot transformation [31].…”