The effects of dietary fiber from lagenaria scineraria (yugao-melon) on colonic carcinogenesis in mice

Abstract

Background. The increasing trend of colon cancer in Japan is attributed to changes in dietary habits, that is, increased amounts of fat and decreased amounts of fiber in the diet. The effects of Japanese dietary fiber from Lagenaria scineraria (yugao‐melon) on colonic carcinogenesis in mice were examined. Methods. Eighteen ICR mice in each group were fed with either a basal diet or a diet containing 5%, 10%, or 20% of yugao powder for 35 weeks. All the mice a weekly intraperitoneal injection of 1,2‐dimethylhydrazine (DMH), 10 mg/kg body weight for 10 weeks. The effects of yugao powder on the mucosal and luminal variables involved in colonic carcinogenesis were then compared with those of wheat bran in the mice without any carcinogen treatment. Results. The incidence of colon tumors (adenocarcinomas) was lower in the yugao powder diet groups than in the basal diet group at week 35 (24% vs. 50%, P < 0.05). The bile acid concentration in the colon was reduced in all the fiber diet groups except for the 5% yugao powder diet group. The colonic luminal pH acidified as yugao powder contents also increased in the yugao powder diet groups. The findings on the colonic short chain fatty acids, microflora, and mucosal fatty acids and ornithine decarboxylase activity were all inconsistent with a tendency to either develop or to inhibit carcinogenesis in both the fiber diet groups. Conclusions. Dietary fiber from yugao‐melon suppressed DMH‐induced colonic carcinogenesis in mice by lowering the bile acid concentration and pH in the colon. The results of the luminal and mucosal variables examined also suggested that the mechanisms of action of yugao powder against colonic carcinogenesis differed from those of wheat bran. Cancer 1995;75:1508‐15.

Antioxidant activity and HPTLC profile of Lagenaria siceraria fruits

“…This includes screening for cytotoxicity, anticancer and antihepatotoxicity properties (Answal et al, 1984;Furukawa et al, 1995;Shiwaikar & Sreenivasan, 1996). Despite the fact that fruits of L. scerara are used as food and for medicinal purposes, there is no information on antioxidant properties.…”

Antioxidant and HPTLC profile of the leaf and fruit extracts of <i>Lagenaria siceraria</i>

“…There is, however, limited information on the pharmacological properties of the fruits and leaves of L. siceraria. Some documented biological activities of the fruits include antimicrobial, cytotoxicity, anticancer and antihepatotoxicity properties (Answar et al, 1984;Desta, 1993;Furukawa et al, 1995;Shiwaikar and Sreenivasan, 1996). Despite the fact that fruits and leaves of L. siceraria are used as food and for medicinal purposes, there is no information on their antioxidant properties, yet, it has been suggested that the etiology of complications of some physiological ailments such as diabetes involves oxidative stress, perhaps as a result of hypoglycemia (Hunt et al, 1990;Govindarayan et al, 2005).…”

Nutritional and Medicinal Potential ofLagenaria siceraria

“…Prebiotics are nondigestible food ingredients that beneficially affect the host by selective stimulation and improvement of growth of one or a limited number of resident enteric microbial populations (Furukawa et al, 1994;Gibson and Roberfroid, 1995). L. siceraria is a rich source of dietary prebiotics and is believed to improve the probiotic populations that affect enteric microbial metabolisms and physiology, leading to synthesis and release of potentially beneficial bimolecular substances.…”

“…Dietary fiber of L. siceraria suppresses progression of colon cancer and improves probiotic bacterial population (Furukawa et al, 1994). Strains of lactic acid-producing bacteria and certain prebiotics inhibit carcinogen-induced DNA damage in colons of rats Rowland et al, 1996).…”

“…L. siceraria have been reported to have a beneficial effect against colon carcinogenesis. The protective effect of L. siceraria powder against colonic carcinogenesis was determined through an additive or synergistic effect by lowering bile acid concentration and colon pH (Furukawa et al, 1994;Wynder and Reddy, 1977). L. siceraria powder changes luminal variables such as bile acids, pH, short-chain fatty acids, and microflora, which all are involved in colonic carcinogenesis (Wynder and Reddy, 1977).…”