Effects of Shikunshito-Kamiho on Fecal Enzymes and Formation of Aberrant Crypt Foci Induced by 1,2-Dimethylhydrazine

Bong-Ha YOO, Beom-Han LEE, Jin-Sung KIM, Nam-Jae KIM, Sung-Hoon KIM, Ki-Won RYU
2001 Biological and Pharmaceutical Bulletin  
Human colorectal cancers are mainly caused by exposure to food mutagens and carcinogens. 1) 1,2-Dimethylhydrazine (1,2-DMH) is a typical colon carcinogen which conjugates with glucuronic acid in liver and is excreted in intestine via the bile. 2) The glucuronide conjugates hydrolysed by bacterial b-glucosidase are known to increase the activities of fecal enzymes such as b-glucuronidase, tryptophanase and urease in metabolic pathways. 3) Aberrant crypt foci (ACF) in colonic mucosa were first
more » ... ucosa were first observed in the carcinogen treated rodent colon 8) and were also known to be putative preneoplastic lesions in colon of both rodents and humans. 4) Induction of K-ras mutation and increased expression of ras and c-fos oncogene products in ACF have been reported 5) suggesting ACF in the rodent colon can be used as a good biomarker in colon carcinogenesis. Chemoprevention is an alternative approach to decrease the carcinogenic effect. Natural chemopreventive agents have inhibitory effects on carcinogenesis. 6) Medicinal plants are also candidates for cancer chemoprevention. Shikunshito-Kamiho (SKTK) is an oriental prescription consisting of eight herbs used for the treatment of colorectal cancer in oriental medicine. 7) However, there wasn't yet any experimental data for SKTK which includes three kinds of sea weeds. Thus, in the present study, we investigated the anticarcinogenic effects of SKTK on 1,2-DMH-induced colorectal cancer in vivo by evaluating pH, ammonia, fecal enzymes such as b-glucuronidase, tryptophanase and urease, and also ACF formation in the murine colon. MATERIALS AND METHODS Animals SPF male ICR mice (18-24 g body weight) were provided by the Laboratory Animal Center, Korea Research Institute of Chemistry and Technology. Mice were in-dividually housed in polycarbonate cages and maintained in a temperature (23Ϯ2°C) and humidity (50Ϯ10%) controlled animal facility with a daily 12 : 12 h light-dark photoperiod. After a 2 week acclimatization period of consuming standard rat chow, the rats were used for the experiment. Materials Medicinal herbs of Shikunshito-Kamiho (SKTK) were purchased from Koryo Company of Traditional Crude Drugs (Seoul, Korea) and kindly authenticated by Dr. Deok-Kyun Ahn, Professor of Department of Herbology, Oriental Medical College, Kyunghee University. SKTK (40.0 g) consists of eight crude drugs (Panax ginseng C. A. MEYER, Astractylodes macrocephala KOIDZUMI, Poria cocos WOLFF, Glycyrrhiza ularensis FISCH, Prunella vulgaris var. lilacina NAKAI, Sargassum pallidum (TURN.) C. AG., Laminaria japonica ARESCH and Ostrea gigas THUBERG). The composition of SKTK, botanical origins, crude drugs, voucher number, harvesting, place and dose of each herb are shown in Table 1 . Voucher specimens were deposited in the herbarium of the Museum of Materia Medica, Oriental Medical College, Kyunghee University, Seoul, Korea. The qualities of medicinal herbs were controlled by Korean Pharmacopeia VII which regulates the botanical origin, the crude drug, loss of drying, total ash, test of foreign matter, acid insoluble ash, extract content, essential oil content and microscopic examination. 14) Preparation of SKTK Extract One and two tenths kilograms of SKTK was mixed and boiled with regular water. The boiled solution was concentrated with rotary evaporator (Model NE-1, Japan) and dried with freeze dryer (Model FD-1, Japan) to obtain 195 g of SKTK extract. The yield of water extract of SKTK was 16.25% (w/w) in terms of the dried medicinal herbs. Usually, the daily dose of SKTK extract in the treatment of human is 19.5 g three times a day. Thus, the daily dose ratio for a mouse was determined as 0.5% and 1.5% of regular diet considering daily food intake (approxi-638 Shikunshito-Kamiho (SKTK) is a traditional Chinese medicine composed of eight crude drugs (Ginseng Radix, Hoelen, Atractylodis Rhizoma, Glycyrrhizae Radix, Prunellae Spica, Ostreae Testa, Laminaria Thallus, Sargassum). We investigated the effects of SKTK on pH, ammonia, fecal enzymes such as b b-glucuronidase, tryptophanase, urease, and formation aberrant crypt foci in the colon carcinogenesis model induced by 1,2-dimethylhydrazine (DMH). Water extract of SKTK was administered orally for 5 weeks to DMH-treated mice as 0.5% and 1.5% of the diet. b b-Glucuronidase, pH and tryptophanase were significantly inhibited after treatment of 0.5% and 1.5% SKTK, while urease was significantly reduced only during and after treatment of 1.5% SKTK as compared with control data. However, the ammonia concentration wasn't different in SKTK treated groups from control group. The incidence number of aberrant crypts foci (ACF) and aberrant crypts/focus in colon was significantly decreased by 0.5% and 1.5% SKTK mixed diets compared with that in rats treated with DMH alone. These results suggest that SKTK exterts anticarcinogenic activity on experimental murine colorectal cancer.
doi:10.1248/bpb.24.638 pmid:11411551 fatcat:5cduwxvsivhijc52v3krxktzvu