Open AccessIn vitro and in vivo evaluation of a novel oral insulin formulation 1
Author(s) -
MA Erli,
MA Hong,
LIU Zheng,
ZHENG Changxue,
DUAN Mingxing
Publication year - 2006
Publication title -
acta pharmacologica sinica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.514
H-Index - 90
eISSN - 1745-7254
pISSN - 1671-4083
DOI - 10.1111/j.1745-7254.2006.00424.x
Subject(s) - paracellular transport , bioavailability , in vivo , pharmacology , insulin , transcellular , beagle , insulin resistance , chemistry , oral administration , medicine , drug delivery , in vitro , drug , permeability (electromagnetism) , biology , biochemistry , microbiology and biotechnology , organic chemistry , membrane
Aim : To develop a stable self‐emulsifying formulation for oral delivery of insulin. Methods : Caco‐2 cell line and diabetic beagles were used as in vitro and in vivo models to study the absorption mechanism and the hypoglycemic efficacy of the formulation. In addition, various physicochemical parameters of the formulation such as droplet size, insulin encapsulation efficiency and stability were evaluated. Results : This formulation enabled changes in barrier properties of Caco‐2 monolayers, as referred by transepithelial electrical resistance (TEER) and apparent permeability coefficients ( P app ) of the paracellular marker ranitidine (20‐fold greater than control) but not transcellular marker propranolol, suggesting that the opening of tight junctions was involved. In diabetic beagle dogs, the bioavailability of this formulation was up to 15.2% at a dose of 2.5 IU/kg in comparison with the hypoglycemic effect of native insulin (0.5 IU/kg) delivered by subcutaneous injection. Conclusion : This formulation, recently approved by the China State Food and Drug Administration to enter clinical trials, was stable, degradation‐protected and absorption‐enhanced, and provided a promising formulation for oral insulin delivery.