posted on 2020-07-31, 22:30authored byYun-Chung Hsiao, Chih-Wei Liu, Liang Chi, Yifei Yang, Kun Lu
The human intestine is host to a
vast microbial community: the
gut microbiome (GM). The GM has been considered as a key modulator
of human health in the past decade. In particular, several studies
have supported that altered GM is associated with cancer, such as
colorectal cancer, adenocarcinoma, and pancreatic cancer. The formation
of a DNA adduct is one of the key events in carcinogenesis, and whether
GM can influence DNA adducts has yet to be examined. This study analyzed
10 DNA adducts (N2-Me-dG, N6-Me-dA, N2-Et-dG, OH-Me-dG, OH-Me-dA, N2-EtD-dG, O6-Me-dG,
1,N2-ε-dG, 8-oxo-dG, and 5-Cl-dC), attributed to
various endogenous processes and physiological stressors, using highly
sensitive LC–MS/MS in germ-free (GF) and conventionally raised
(CONV-R) mice. Our results showed that significant differences in
specific DNA adducts appeared in liver, colon, and small intestine
samples between GF and CONV-R mice. The differences in adduct levels
may indicate that GM can locally or systemically regulate endogenous
processes including neutrophil bactericidal activity (represented
by 5-Cl-dC), lipid peroxidation (1,N2-ε-dG), oxidative
stress generation (8-oxo-dG), and endogenous aldehyde metabolism (OH-Me-dA).
Further studies are warranted to elucidate how the GM influences endogenous
process, DNA damage, and the risks of developing cancer.