Analysis of Drug Permeation Mechanism across Oral Mucosa Using Cultured Stratified Cell Layers

2004 Fiscal Year Final Research Report Summary

• Project/Area Number: 15590131
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Medical pharmacy
• Research Institution: OKAYAMA UNIVERSITY
• Principal Investigator: KIMURA Toshikiro Okayama University, Faculty of Pharmaceutical Sciences, Professor, 薬学部, 教授 (10025710)
• Co-Investigator(Kenkyū-buntansha): HIGAKI Kazutaka Okayama University, Faculty of Pharmaceutical Sciences, Associate Professor, 薬学部, 助教授 (60284080) ; OGAWARA Ken-ichi Okayama University, Graduate School of Natural Science and Technology, Research Associate, 大学院・自然科学研究科, 助手 (30291470)
• Project Period (FY): 2003 – 2004
• Keywords: oral mucosa / permeability evaluation / HaCaT cells / stratified cell layer / optimal culture condition / D-glucose transport

Research Abstract

In order to clarify the drug permeation mechanism across oral mucosa, the optimal culture condition for the stratified cell layer using HaCaT cells was determined and the various basic studies were performed on glucose transport systems.
As to the culture condition for HaCaT cells, DMEM EGF(+) or DMEM+Supplement EGF(+) was selected from the point of proliferative activity. From histological view point, DMEM EGF(+) was selected. From the transmucosal electrical resistance, DMEM : Ham's F-12 EGF(+) was the best. Taking factors such as cell viability, stratification, transmucosal electrical resistance and glucose transport into consideration, the best condition for HaCaT cell layers was selected to be the culture for 3 to 4 weeks using DMEM EGF(+).
The result of glucose transport experiments using HaCaT cells showed that the uptake of D-glucose into cells was much faster than that of L-glucose, suggesting that the expression of stereo-selective glucose transporters in HaCaT cells. Western blot analysis showed that the presence of SGLT, GLUTs 1,2 and 3. Nevertheless, the transport rate of D-glucose across the cell layer was not significantly different from that of L-glucose. The reason for this observation is remaining unsolved.
As the passively transported drugs, mannitol, melatonin and estradiol were selected, and the Papp values were measured. The results of Papp values for the three drugs were correlated with their lipophilicity, suggesting that the cultured HaCaT cell layers are effective for the evaluation of the oral-mucosal permeability to passively transported drugs.