Effect of plaunotol in combination with clarithromycin against clarithromycin-resistant Helicobacter pylori in vitro and in vivo.
OBJECTIVE
Recently, there has been a decrease in the eradication rate of Helicobacter pylori due to the increase in antibiotic resistance of this bacterium. Plaunotol, a cytoprotective anti-ulcer agent, exhibits antibacterial activity against H. pylori. The purpose of the present study was to investigate the effect of plaunotol in combination with clarithromycin against clarithromycin-resistant H. pylori clinical isolates.


RESULTS
In the chequerboard titration method, the combination of plaunotol and clarithromycin showed a synergistic effect against 67% (10/15) clarithromycin-resistant strains and an additive effect against the other strains. No indifferent and antagonistic effects were observed against any of the strains tested. In a gastritis model of Mongolian gerbils infected with clarithromycin-resistant H. pylori, the plaunotol (40 mg/kg) and clarithromycin (66.6 mg/kg) combination exhibited synergistic effects; however, neither plaunotol nor clarithromycin alone showed bactericidal effects.


CONCLUSIONS
These results suggest that plaunotol may play a useful role in combination with anti-H. pylori drugs in the treatment of diseases associated with clarithromycin-resistant H. pylori.
Sasaki
Makoto
M
Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho, Nagoya 467-8601, Japan. msasaki@med.nagoya-cu.ac.jp
Mizoshita
Tsutomu
T
Mizushima
Takashi
T
Inoue
Harumi
H
Kamiya
Takeshi
T
Kataoka
Hiromi
H
Ogaswara
Naotaka
N
Wada
Tsuneya
T
Kubota
Eiji
E
Mori
Yoshinori
Y
Shimura
Takaya
T
Hirata
Hirokazu
H
Ando
Kenji
K
Okamoto
Yasuyuki
Y
Ohara
Hirotaka
H
Nakao
Haruhisa
H
Joh
Takashi
T
D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use; D017291:Clarithromycin / Q000008:administration & dosage* / Q000627:therapeutic use*; D004224:Diterpenes; D024881:Drug Resistance, Bacterial; D004359:Drug Therapy, Combination; D005233:Fatty Alcohols / Q000008:administration & dosage* / Q000627:therapeutic use*; D014644:Genetic Variation; D005849:Gerbillinae; D016481:Helicobacter Infections / Q000188:drug therapy*; D016480:Helicobacter pylori / Q000187:drug effects* / Q000235:genetics; D008297:Male; D008826:Microbial Sensitivity Tests; D013047:Specific Pathogen-Free Organisms