Determination of intestinal absorption of the paralytic shellfish toxin GTX-5 using the Caco-2 human cell model

Re-Use of Caco-2 Monolayers in Permeability Assays—Validation Regarding Cell Monolayer Integrity

“…In this case, it is observed that a Normal distribution centered at around −0.6 is obtained for LogQ A during both sampling intervals (10 or 60 min), corresponding to Q A around 0.2% (for details see the Supplementary Material-Table S4). A very similar amount of LY was also observed to permeate through Caco-2 monolayers on day 23 post-seeding during a 90 min sampling interval, 0.27% [30]. This shows that, for cell monolayers on day 22 post-seeding, manipulation of the cell monolayer during the permeability assay leads to a significant amount of LY transport and that very little permeation is observed during the sampling time interval, thus leading to P app values that are strongly dependent on the sampling time interval.…”

“…This test may be carried out in dedicated cell monolayer inserts prepared from the same batch of cells, or in the same monolayer insert, before or after the test compound (in this case providing additional evidence for eventual toxicity) [46]. With a view to reducing the duration of the incubations with the transport media and the manipulations of the cell monolayers, a better approach is to evaluate the permeability of both the control (LY) and test compounds in the same Transwell™ [30,34]. This procedure has the advantage of including a quality control for each filter, thus facilitating the identification of cell monolayers with compromised integrity (outliers), and therefore decreasing the variability.…”

“…Although this approach has been shown to be valid for some groups of test molecules, it cannot be followed for poorly defined compounds due to possible interferences such as, for example, the coexistence of substrates and inhibitors of P-glycoprotein. An interesting compromise is the combination of a well-defined control marker and the unknown test compound, as has been done previously [29,30].…”

“…An extensive characterization has therefore been performed for a two-day incubation period, with consecutive permeability assays being performed at days 22, 25, and 28 after seeding. Single sampling (at 60 min) and multi-time sampling (10,20,30, and 60 min) was evaluated to support the applicability of the cell monolayer re-use when following both procedures.…”

Elucidation of the Transport Mechanism of Puerarin and Gastrodin and Their Interaction on the Absorption in a Caco-2 Cell Monolayer Model

“…The Caco-2 cell line was derived from human colon adenocarcinoma and its morphology and function are similar to those of human intestinal epithelial cells, and it contains enzymes related to the brush border epithelium of small intestine [24]. Caco-2 cell model has been widely used in the study of drug uptake, efflux, transmembrane transport and other absorption mechanisms at home and abroad in the past decade because of its good correlation, reproducibility and applicability with oral drug absorption in intestinal tract [25][26][27][28][29].…”