Apical Shear Stress Enhanced Organic Cation Transport in Human OCT2/MATE1-Transfected Madin-Darby Canine Kidney Cells Involves Ciliary Sensing

Abstract

Active transport by renal proximal tubules plays a significant role in drug disposition. During drug development, estimates of renal excretion are essential to dose determination. Kidney bioreactors that reproduce physiologic cues in the kidney, such as flowinduced shear stress, may better predict in vivo drug behavior than do current in vitro models. In this study, we investigated the role of shear stress on active transport of 4-(4-(dimethylamino)styryl)-N-methylpyridinium iodide (ASP1) by Madin-Darby canine kidney cells exogenously expressing the human organic cation transporters organic cation transporter 2 (OCT2) and multidrug and toxin extrusion protein 1 (MATE1). Cells cultured in a parallel plate under continuous media perfusion formed a tight monolayer with a high barrier to inulin. In response to increasing levels of shear stress (0.2-2 dynes/cm 2), cells showed a corresponding increase in transport of ASP1, reaching a maximal 4.2-fold increase at 2 dynes/cm 2 compared with cells cultured under static conditions. This transport was inhibited with imipramine, indicating active transport was present under shear stress conditions. Cells exposed to shear stress of 2 dynes/cm 2 also showed an increase in RNA expression of both transfected human and endogenous OCT2 (3.7-and 2.0-fold, respectively). Removal of cilia by ammonium sulfate eliminated the effects of shear on ASP1 transport at 0.5 dynes/cm 2 with no effect on ASP1 transport under static conditions. These results indicate that shear stress affects active transport of organic cations in renal tubular epithelial cells in a cilia-dependent manner.

Bridging the gap between in silico and in vivo by modeling opioid disposition in a kidney proximal tubule microphysiological system

“…IVIVE approaches usually assume that the tubular secretion is determined by only OAT-mediated transport and do not consider other transporters such as OCT2, OATP4C1 or unknown transporter(s) that may also contribute to net kidney secretion 2 . Although PTEC monolayers in 2D Transwell may help evaluate kidney secretion of drugs by evaluation of directional transport, our previous investigations failed to observe active transport of probe substrates of kidney transporters 5 presumably because the lack of fluid shear stress in the Transwell system results in the loss of transporter expression 6 .…”

Improved cultivation of CHO cells in bioreactor with reciprocal mixing

“…Influence of shear stress on cell damage has been investigated not only in bioreactors, but also in microfluid devices and blood vessels (Mitchell, 2013;Odeleye, 2014;Model, 2014). Although many researchers have tried to clarify how shear stress affects gene expression and physiological conditions (Nurhayati, 2018;Jayagopal, 2019), the kind of cellular systems that sense the effect of shear stress on gene expression still remains unknown. Even if a type of shear stress induced gene expression in one cell type, it may not affect the same in other cell lines (Akimoto, 2000;Novak, 2019).…”

Bridging the gap betweenin silicoandin vivo:modeling opioid disposition in a kidney proximal tubule microphysiological system

“…Although PTEC monolayers in 2D Transwell TM may help evaluate kidney secretion of drugs by evaluation of directional transport, our previous investigations failed to observe active transport of probe substrates of kidney transporters (5) presumably because the lack of fluid shear stress in the Transwell TM system results in the loss of transporter expression (6).…”