Early biochemical events in mice exposed to cycas and fed a Nigerian-like diet.

Changes in colonic faecal microflora, enzymes of colonic energy metabolism, of cell proliferation and lipid profile in the serum and colon were studied in 48 mice exposed to cycas and fed a Nigeria-type diet. The animals were divided into three diet classes of 16 mice per class, and each class of animals was fed ad libitum either a normal diet, a high-carbohydrate high-fibre (HCF) diet or a high-protein high-fat (HPF) diet. Each diet class was subdivided into two equal groups of 8 animals each. One group was fed a diet type (acted as the diet control) without cycas, and the other group was fed the corresponding diet with cycas. The study period lasted for 3 weeks. The colonic faecal materials were acidified in the HCF-fed mice compared with the other diet-fed mice. Faecal beta-glucuronidase activity was significantly (p < 0.05) increased in the cycas-fed mice compared with the diet controls. Feeding mice with the HPF diet significantly (p < 0.05) increased beta-glucuronidase and mucinase activities. Colonic phosphofructokinase, glucose 6-phosphate dehydrogenase, lactate dehydrogenase and hyaluronidase activities were also significantly (p < 0.05) elevated in the cycas-treated mice. Feeding mice with the HPF diet also significantly (p < 0.05) increased these enzyme activities. Mice fed with the HCF diet significantly (p < 0.05) lowered serum total cholesterol, triglyceride and colonic total lipid. Colonic phosphatidylethanolamine and phosphatidylcholine were significantly (p < 0.05) increased in the HPF-fed mice. This study shows that the HCF diet alters the colonic faecal environment, colonic energy metabolism and hyaluronidase activity in ways which suggest its protective ability against the development of colon cancer in mice.