Related Experiment Video
Updated: Aug 8, 2026

Using Caco-2 Cells to Study Lipid Transport by the Intestine
Published on: August 20, 2015
Absorption enhancement study of astragaloside IV based on its transport mechanism in caco-2 cells
1Drug Metabolism and Pharmacokinetic Research Center, China Pharmaceutical University, Nanjing, People's Republic of China.
Abstract:
The purpose of this study was to investigate the transport characteristics and mechanisms for discovering the possible causes of the low bioavailability of astragaloside IV and to develop an absorption enhancement strategy. Caco-2 cells used as the in vitro model. Results showed a low permeability coefficient (3.7 x 10(-8)cm/s for transport from the AP to BL direction), which remained unchanged throughout the concentration range studied, indicating that the transport of astragaloside IV was predominantly via a passive route. The AP to BL transport of astragaloside IV was found to be highly sensitive to the extracellular Ca2+ concentration, which suggested that its transport may be via a paracellular route. Both chitosan and sodium deoxycholate can increase the permeation efficiency of astragaloside IV. This study indicated that astragaloside IV having a low fraction dose absorbed in humans mainly due to its poor intestinal permeability, high molecular weight, low lipophilicity as well as its paracelluar transport may directly result in the low permeability through its passive transport. Meanwhile, chitosan and sodium deoxycholate can be used as absorption enhancers based on its transport mechanism.
Related Concept Videos
Methods for Studying Drug Absorption: In vitro
The diffusion cell method uses a two-compartment cell, including a donor compartment with the drug solution, which simulates the environment where the drug is applied, and a receptor compartment with a buffer solution, which simulates the environment...
Methods for Studying Drug Absorption: In situ
The Doluisio method involves perfusing a prepared segment of a rat's small intestine with a solution of radiolabeled drug and a non-absorbable marker. This helps to differentiate between absorbed and non-absorbed drug concentrations. The intestinal segment is connected at both ends using tubing and syringes,...
Carrier-Mediated Transport
Active transport involves two types of membrane-spanning transporters: uptake and efflux. Uptake transporters are expressed in the small...
Factors Influencing Drug Absorption: Anatomical Parameters
Drug Absorption: Overview
When drugs are injected intravenously, they directly enter the systemic circulation. Alternatively, orally administered drugs navigate through the gastrointestinal (GI) tract.
Drug Absorption: Factors Affecting GI Absorption
In...

