The metabolism of chlorogenic acid
(CGA) through the intestinal
tract was studied. As cadmium is a well-known toxic heavy metal, this
study was carried out to investigate the comparative protective effect
of CGA and its representative intestinal metabolite (3-(3-hydroxyphenyl)
propionic acid, HPPA) against Cd-induced erythrocyte cytotoxicity in vitro and in vivo. We found that CGA
and its intestinal metabolite appreciably prevented erythrocyte hemolysis,
osmotic fragility, and oxidative stress induced by Cd. Also, we found
that HPPA had a stronger protective ability than CGA against Cd-induced
erythrocyte injury in vivo, such as increasing the
ratio of protein kinase C from 7.7% (CGA) to 12.0% (HPPA). Therefore,
we hypothesized that CGA and its microbial metabolite had protective
effects against Cd-induced erythrocyte damage via multiple actions
including antioxidation and chelation. For humans, CGA supplementation
may be favorable for avoiding Cd-induced biotoxicity.