| 摘要: | 大腸癌為全球最常見癌症之第三名，腸道慢性且反覆發炎引起腸道損傷是造成大腸癌的重要原因。本研究以1,2-dimethylhydrazine（DMH）/dextran sodium sulfate（DSS）誘發大鼠大腸癌模擬發炎相關大腸癌（colitis-associated colorectal cancer），探討餵食精白米、糙米及發芽糙米對大腸癌前期病變之預防效果。本研究將雄性Fisher 344大鼠分為十組：正常組（B）、負控制組（NC）、正控制組（PC）、40%精白米組（PR）、10%糙米組（低劑量糙米組，LB）、20%糙米組（中劑量糙米組，MB）、40%糙米組（高劑量糙米組，HB）、10%發芽糙米組（低劑量發芽糙米組，LG）、20%發芽糙米組（中劑量發芽糙米組，MG）及40%發芽糙米組（高劑量發芽糙米組，HG），經過15週的實驗期後，發現低劑量發芽糙米顯著減少異常腺窩病灶（aberrant crypt foci，ACF）數、含有一個異常腺窩之ACF數及小型ACF數。精白米、糙米及發芽糙米皆顯著降低大腸黏膜nuclear factor-kappa B（NF-κB）及cycloxygenase-2（COX-2）蛋白表現量及血清中tumor necrosis factor-α（TNF-α）濃度，糙米及低劑量發芽糙米顯著降低血清interleukin-1β（IL-1β）及interleukin-6（IL-6）濃度。以上結果顯示低劑量發芽糙米具有預防大腸癌前期病變的效果，其作用機制可能與抑制發炎反應有關。
Colorectal cancer is the third most commonly diagnosed cancer in the world. Chronic and repeated mucosal inflammation play an important role in the occurrence of colorectal cancer. This study investigated the preventive effects of polished rice (PR), brown rice (BR) and germinated brown rice (GBR) on preneoplastic lesions of colitis-associated colorectal cancer in rats induced by 1,2-dimethylhydrazine (DMH) and dextran sulfate sodium (DSS). Male Fisher 344 rats were divided into ten groups: blank (B group), negative control (NC group), positive control (PC group), 40% PR (PR group), 10% BR (low dose of BR, LB group), 20% BR (medium dose of BR, MB group), 40% BR (high dose of BR, HB group), 10% GBR (low dose of GBR, LG group), 20% GBR (medium dose of GBR, MG group) and 40% GBR (high dose of GBR, HG group). After 15 weeks of experimental period, the results showed that LG significantly reduced the numbers of colonic aberrant crypt foci (ACF), ACF containing 1 crypt and small ACF. PR, BR and GBR significantly reduced colonic mucosal nuclear factor-kappa B (NF-κB), cycloxygenase-2 (COX-2) expression and serum tumor necrosis factor-α (TNF-α) level. BR and LG significantly reduced serum interlukin-1β (IL-1β) and interleukin-6 (IL-6) levels. The results indicate that LG may prevent preneoplastic lesions of colorectal cancer by suppression of inflammatory response. |
