Effect of polaprezinc on taste disorders in zinc-deficient rats.
The effect of polaprezinc, a chelate compound consisting of zinc ion and L-carnosine, on abnormalities of taste sensation induced by feeding a zinc-deficient diet to rats was examined by using the two-bottle preference test (quinine hydrochloride as a bitter taste and sodium chloride as a salty taste). Rats were fed either a zinc-deficient or a zinc-sufficient diet. The zinc-deficient diet increased the preference for both taste solutions, while polaprezinc (at doses of 3 and 10 mg/kg) restored the altered taste preferences. We also evaluated the proliferation of taste bud cells using 5-bromo-2'-deoxyuridine (BrdU). The BrdU incorporation into taste bud cells was significantly reduced in rats fed a zinc-deficient diet compared with rats fed a zinc-sufficient diet (from 50.8% to 45.0%, p<0.05) and this reduction was reversed by polaprezinc at doses of 1, 3, and 10 mg/kg, increasing to 50.2%, 53.5%, and 52.5%, respectively. These findings indicate that zinc deficiency induces the delayed of proliferation of taste bud cells, while polaprezinc improves cell proliferation. In conclusion, polaprezinc had a therapeutic effect in a rat model of abnormal taste sensation. Its mechanism of action was suggested to involve improvement of the decrease in taste bud cell proliferation caused by zinc deficiency.
Hamano
Hiroki
H
Central Research Laboratories, Zeria Pharmaceutical Co., Ltd., Saitama, Japan. hiroki-hamano@zeria.co.jp
Yoshinaga
Koji
K
Eta
Runa
R
Emori
Yutaka
Y
Kawasaki
Daisuke
D
Iino
Yuka
Y
Sawada
Miwa
M
Kuroda
Hiroyuki
H
Takei
Mineo
M
D000818:Animals; D001973:Bromodeoxyuridine / Q000378:metabolism; D002336:Carnosine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D049109:Cell Proliferation / Q000187:drug effects; D008297:Male; D009942:Organometallic Compounds / Q000627:therapeutic use*; D011803:Quinine; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D012965:Sodium Chloride; D013649:Taste / Q000187:drug effects; D013650:Taste Buds / Q000166:cytology; D013651:Taste Disorders / Q000188:drug therapy*; D015032:Zinc / Q000097:blood / Q000172:deficiency*; D017967:Zinc Compounds / Q000627:therapeutic use
D009942:Organometallic Compounds; D017967:Zinc Compounds; C061957:polaprezinc; D012965:Sodium Chloride; D002336:Carnosine; D011803:Quinine; D001973:Bromodeoxyuridine; D015032:Zinc