Chitosan capsules for colon-specific drug delivery: improvement of insulin absorption from the rat colon
Autor: | Akira Yamamoto, Shozo Muranishi, Hideyuki Tozaki, Chika Tada, Junta Komoike, Takako Maruyama, Akira Terabe, Tsutomu Suzuki |
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Rok vydání: | 1997 |
Předmět: |
Blood Glucose
Male medicine.medical_specialty Colon medicine.medical_treatment Pharmaceutical Science Capsules Chitin Absorption (skin) Intestinal absorption Dosage form Chitosan chemistry.chemical_compound Drug Delivery Systems Oral administration Internal medicine Intestine Small medicine Animals Hypoglycemic Agents Insulin Intestine Large Rats Wistar Cecum Rats Endocrinology chemistry Intestinal Absorption Drug delivery Microscopy Electron Scanning Liberation |
Zdroj: | Journal of pharmaceutical sciences. 86(9) |
ISSN: | 0022-3549 |
Popis: | The objective of this study was to estimate colon-specific insulin delivery with chitosan capsules. In vitro drug release experiments from chitosan capsules containing 5(6)-carboxyfluorescein (CF) were carried out by the Japan Pharmacopoeia (J. P.) rotating basket method with some slight modifications. The intestinal absorption of insulin was evaluated by measuring the plasma insulin levels and its hypoglycemic effects after oral administration of the chitosan capsules containing insulin and additives. Little release of CF from the capsules was observed in liquid 1, an artificial gastric juice (pH 1), or in liquid 2, an artificial intestinal juice (pH 7). However, the release of CF was markedly increased in the presence of rat cecal contents. A marked absorption of insulin and a corresponding decrease in plasma glucose levels was observed following the oral administration of these capsules that contain 20 IU of insulin and sodium glycocholate (PA% = 3.49%), as compared with the capsules containing only lactose or only 20 IU of insulin (PA% = 1.62%). The hypoglycemic effect started from 8 h after the administration of chitosan capsules when the capsules entered the colon, as evaluated by the transit time experiments with chitosan capsules. These findings suggest that chitosan capsules may be useful carriers for the colon-specific delivery of peptides including insulin. |
Databáze: | OpenAIRE |
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