Hepatic LDL Receptor mRNA in Rats Is Increased by Dietary Mushroom (Agaricus bisporus) Fiber and Sugar Beet Fiber

Abstract

Plasma cholesterol concentration is reduced by feeding some dietary fibers and mushroom fruit body, but the mechanism is not fully understood. We examined the effects of mushroom (Agaricus bisporus) fiber and sugar beet fiber on serum cholesterol and hepatic LDL receptor mRNA in rats. Rats were fed a cholesterol-free diet with 50 g/kg cellulose powder (CP), 50 g/kg mushroom (Agaricus bisporus) fiber (MSF) or 50 g/kg sugar beet fiber (BF) for 4 wk. There were no significant differences in the body weight, food intake and cecum weight among the groups. The relative liver weight in the CP group was significantly greater than that in the MSF and BF groups. The cecal pH in the CP and MSF groups was significantly higher than that in the BF group. Cecal acetic acid, butyric acid and total short-chain fatty acid (SCFA) concentrations in the BF group were significantly higher than those in the other groups. The serum total cholesterol, VLDL + intermediate density lipoprotein (IDL) + LDL cholesterol concentrations in the CP group were significantly greater than those in the MSF and BF groups. The HDL cholesterol concentration in the MSF group was significantly lower than that in the CP group. The hepatic LDL receptor mRNA level in the MSF and BF groups was significantly higher than that in the CP group. The results of this study demonstrate that mushroom fiber and sugar beet fiber lowered the serum total cholesterol level by enhancement of the hepatic LDL receptor mRNA.

Mushrooms as therapeutic agents

“…Fibers, ethanolic extracts Antioxidant (Wang et al, 1995(Wang et al, & 1996, Hypocholesterolemic (Fukushima et al, 2000(Fukushima et al, & 2001, Antiallergic (Sano et al, 2002) Grifola frondosa (Dicks.) Gray MD-fraction, ergosterol (1) Antioxidant (Wang et al, 1995(Wang et al, & 1996, hypotensive, Hypoglycemic (Horio et al, 2001), Immunotherapy (Hazama et al, 1995), Antiinflammatory activity (Zhang et al, 2002) Ganoderma lucidum (Curtis) P. Karst Ganoderan A and B, glucans, Triterpenes (ganoderiol F (2), ganodermanontriol (3), ganoderic acids (4) A, B, D, F, G, H, Z), ganosporeric acid A, ganopoly, the polysaccharide-containing preparation Hypoglycemic (Hikino et al, 1985), antioxidant and antitumor (Thekkuttuparambil et al, 2007), antiviral (HIV-1) (El-Mekkawy et al, 1998), Antiallergic (Kohda et al, 1985;Tasaka et al, 1988), Anti-inflammatory (Koyama et al, 1997), antihepatotoxic (Hirotani et al, 1986;Chen & Yu, 1993, inhibit the biosynthesis of cholesterol (Komoda et al, 1989), antioxidative and free radical scavenging effects (Lin, 2004) Ganoderma pfeifferi Bres.…”

“…Furthermore, exopolysaccharides produced by the submerged fermentation of the mycelium of V. volvacea can reduce the levels of serum TC, LDL cholesterol, and liver TC in alimentarially induced hypercholesterolemic rats . Fibers from F. velutipes (enokitake mushroom) and A. bisporus (button mushroom) can dramatically enhance the hepatic LDL receptor messenger RNA (mRNA), causing the diminution of the serum TC (Fukushima et al, 2000;Fukushima et al, 2001).…”

Effects of ultrasound and chemical treatments on white mushroom (Agaricus bisporus) prior to modified atmosphere packaging in extending shelf-life

“…White mushroom (Agaricus bisporus) is rich in acidic polysaccharides, dietary fiber, and antioxidants including vitamins C, B12, and D; folate; ergothioneine; and polyphenol (Fukushima et al 2000;Mattila et al 2001). This nutrient rich vegetable may have potential anti-inflammatory, hypoglycemic, and hypocholesterolemic effects.…”

Effect of White Wheat Bread Containing Sugar Beet Fiber on Serum Lipids and Hepatic mRNA in Rats Fed on a Cholesterol-Free Diet

“…4) Fukushima et al have also reported that sugar beet fiber lowered the serum total cholesterol level by enhancing hepatic LDL receptor mRNA. 5) Shortchain fatty acids (SCFAs), particularly propionate, a fermentable metabolite of soluble fiber, may be involved in lowering the serum cholesterol concentration. 6,7) The effect of fiber on plasma triacylglycerol is mainly from such gel-forming fiber as pectin which influences the functional properties of the intestinal mucosa by slowing upper intestinal transit.…”