Effects of Dietary Corn Bran Hemicellulose and Neomycin on Hepatic Caspase-3 Activity and Glycoprotein Concentration in Rats Treated with or without D-Galactosamine

Abstract

SummaryThe effects of dietary corn bran hemicellulose (CBH) and neomycin (Neo) on hepatic caspase-3 activity and glycoprotein concentration were investigated to explore the possible mechanism of the alleviative action of dietary CBH and Neo on the development of D -galactosamine (GalN)-hepatitis. Rats were fed a diet containing 5% CBH with or without neomycin (Neo) for 7 or 14 d. On the last day of feeding, the rats were treated with GalN (400 mg/kg body weight, i.p.), and their plasma transaminase activities, hepatic glycoprotein concentrations and hepatic caspase-3 activities were determined 6 or 24 h later. Although the elevations of plasma transaminase activities were suppressed by CBH or Neo 24 h after GalN-treatment, the activities were not affected by CBH or Neo at an early stage (6 h) of GalN action. At 6 h, hepatic caspase-3 activity was elevated by CBH diet alone as high as that of the GalN-injected control-diet group, and the activity was not elevated further by GalN. At the same time, both GalN-treatment and CBH feeding reduced the hepatic glycoprotein (Mw. 64,000-74,000) concentration, but Neo did not affect the caspase activity or the glycoprotein concentration. These results suggest that dietary CBH elevates hepatic caspase-3 activity and reduces hepatic glycoprotein concentration, and may imply that CBH would suppress GalN-hepatitis not at the early-or middle-step of apoptosis but at the late-step of apoptosis or necrosis, although the relation between these phenomena and the alleviative effects of CBH and Neo on GalN-induced hepatitis is yet to be clarified.

Effect of Dietary Fiber in Edible Seaweeds on the Development of D-Galactosamine-Induced Hepatopathy in Rats

“…Since NEO in a diet itself has been known to repress the development of D-GalN-induced hepatic injury (8), the amount of D-GalN administered to the groups in experiment 1 was fairly higher than those used in the experiments for typical development of hepatic injury, such as experiment 2 in the present study. Although many substances contained in food materials were demonstrated to have the ability to repress the development of D-GalN-induced hepatic injury (1,(8)(9)(10)(11), the components in these seaweeds responsible for the alleviation of the hepatopathy would be estimated to be the non-digestible substances such as dietary fiber and oligosaccharides, which could affect the function of the intestinal bacteria, because such an alleviative effect was diminished by the antibiotic NEO.…”

“…Based on previous studies, bacterial translocation in D -GalN-hepatopathy was reduced by intestinal excision or by using an antibiotic which reduces intestinal bacteria in the gut of the animals before D -GalNtreatment ( 7 ). We have investigated the effect of several saccharides, such as arabinoxylan and lactulose, on the development of D -GalN and pointed out that the action of intestinal bacteria was necessary for its protective effects (8)(9)(10)(11). Although seaweed contains some kinds of polysaccharides, which are quite different from the saccharides in the land plant, we considered that it might be useful to take the information from previous studies into consideration in order to investigate the influence of seaweed on the D -GalN-hepatopathy.…”