The controlled release of insulin-mimetic metal ions by the multifunction of chitosan.
Vanadium, which is an insulin-mimetic metal ion, was efficiently adsorbed on chitosan (CS). The adsorption of vanadium on CS was affected by the vanadium/CS ratio and the initial concentration of vanadium in preparative medium under constant pH condition. The vanadium-CS complex was able to control vanadium release. Moreover, a consistent control of vanadium release was achieved by incorporation of the vanadium-CS complex into a CS gel. After implantation of the CS gel retaining the vanadium-CS complex into diabetic mice, insulin-mimetic efficacy was confirmed by observation of a steady reduction in blood glucose levels. The sustained vanadium release also contributed to minimization of the side-effects. Thus, CS gel retaining the vanadium-CS complex appears promising as a vehicle for vanadium with long-term action and a low toxicity leading to its clinical use.
Kofuji
Kyoko
K
Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3, Kanagawa-machi, Kanazawa 920-1181, Japan. k-kofuji@hokuriku-u.ac.jp <k-kofuji@hokuriku-u.ac.jp>
Qian
Chun-Jun
CJ
Murata
Yoshifumi
Y
Kawashima
Susumu
S
D000327:Adsorption; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D048271:Chitosan; D003692:Delayed-Action Preparations; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000188:drug therapy; D004343:Drug Implants; D005782:Gels; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007328:Insulin; D008297:Male; D051379:Mice; D018716:Molecular Mimicry; D014639:Vanadium / Q000008:administration & dosage* / Q000633:toxicity
D001786:Blood Glucose; D003692:Delayed-Action Preparations; D004343:Drug Implants; D005782:Gels; D007328:Insulin; D014639:Vanadium; D048271:Chitosan