Gastric acid reduction leads to an alteration in lower intestinal microflora.
To clarify the alterations in lower intestinal microflora induced by gastric acid reduction, the dynamics of 12 major genera or groups of bacteria comprising the microflora in feces and colonic contents were examined by quantitative real-time PCR in proton pump inhibitor-treated rats and in asymptomatic human subjects with hypochlorhydria. In both rat and human experiments, most genera or groups of intestinal microflora (facultative and obligate anaerobes) proliferated by gastric acid reduction, and marked and significant increases in the Lactobacilli group and Veillonella, oropharyngeal bacteria, were observed. In rats, potent gastric acid inhibition led to a marked and significant increase of intestinal bacteria, including the Bacteroidesfragilis group, while Bifidobacterium, a beneficial bacterial species, remained at a constant level. These results strongly indicate that the gastric acid barrier not only controls the colonization and growth of oropharyngeal bacteria, but also regulates the population and composition of lower intestinal microflora.
Kanno
Takayuki
T
Department of Gastroenterology, Wakayama Medical University, Japan.
Matsuki
Takahiro
T
Oka
Masashi
M
Utsunomiya
Hirotoshi
H
Inada
Kenichi
K
Magari
Hirohito
H
Inoue
Izumi
I
Maekita
Takao
T
Ueda
Kazuki
K
Enomoto
Shotaro
S
Iguchi
Mikitaka
M
Yanaoka
Kimihiko
K
Tamai
Hideyuki
H
Akimoto
Shigeru
S
Nomoto
Koji
K
Tanaka
Ryuichiro
R
Ichinose
Masao
M
D000328:Adult; D000818:Animals; D001419:Bacteria / Q000145:classification* / Q000302:isolation & purification; D003106:Colon / Q000382:microbiology*; D005260:Female; D005744:Gastric Acid / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D051381:Rats; D017208:Rats, Wistar