Transport of insulin in modified Valia-Chien chambers and Caco-2 cell monolayers.
The transport characteristics of insulin were investigated using two different absorption models. Using the modified Valia-Chien chambers, permeability coefficients of insulin in the duodenum, jejunum, and ileum were 0.71x10(-7), 7.11x10(-7) and 9.45x10(-7) cm/s, respectively. In the Caco-2 cell monolayers, the bidirectional transepithelial fluxes of insulin across Caco-2 cell line showed symmetry. Confocal laser scanning microscopy visualized that FD-4 and FITC-insulin were mainly located in the paracellular route. It is evident that the lower intestine might be an advantageous region, and absorption enhancer that helps open tight junctions between cells should be used for oral delivery of insulin.
Tang
Cui
C
State Key Laboratory of Genetic Engineering, Department of Pharmaceutical Sciences, School of Life Sciences, Fudan University, Shanghai, P.R. China.
Yu
Jing
J
Yin
Lichen
L
Yin
Chunhua
C
Pei
Yuanying
Y
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000818:Animals; D001692:Biological Transport; D018938:Caco-2 Cells; D004386:Duodenum / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D006801:Humans; D007004:Hypoglycemic Agents / Q000493:pharmacokinetics*; D007082:Ileum / Q000378:metabolism; D007328:Insulin / Q000493:pharmacokinetics*; D007408:Intestinal Absorption; D007583:Jejunum / Q000378:metabolism; D008297:Male; D018613:Microscopy, Confocal; D008954:Models, Biological; D010539:Permeability; D051381:Rats; D017207:Rats, Sprague-Dawley
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D005456:Fluorescent Dyes; D007004:Hypoglycemic Agents; D007328:Insulin; D016650:Fluorescein-5-isothiocyanate