可可粉是巧克力的成分之一,，可可粉中含有很多黃酮類成分,，還包括如原花青素、兒茶酚等在預(yù)防心血管疾病中發(fā)揮重要作用的化學(xué)成分,。
近日,，一項由食品科學(xué)技術(shù)與營養(yǎng)協(xié)會科研人員主持的研究表明：實驗動物在攝取可可粉后，可以幫助動物預(yù)防因氧化性應(yīng)激損傷有關(guān)的腸道疾病,，對化學(xué)致癌物質(zhì)誘發(fā)的結(jié)腸癌有預(yù)防作用,。相關(guān)研究論文發(fā)表在Molecular Nutrition & Food Research雜志上。
研究人員用小鼠動物實驗首次證實了可可粉中的黃酮類成分有預(yù)防結(jié)腸癌的功效,。實驗開始時,，工作人員一直用含可可粉的飼料（含量占12%）喂養(yǎng)小鼠，8周后用化學(xué)復(fù)合物氧化偶氮甲烷誘導(dǎo)小鼠腫瘤發(fā)生,。
用化學(xué)藥物誘導(dǎo)刺激小鼠4周后,，正常對照小鼠腫瘤病變前腸道部位開始出現(xiàn)腸道粘液，腸道粘液是結(jié)腸癌發(fā)病的標(biāo)志物,。而用含可可粉當(dāng)飼料的小鼠在致癌劑的誘導(dǎo)下,，小鼠出現(xiàn)結(jié)腸癌的只數(shù)明顯少于對照組。同時研究人員在食用含可可粉當(dāng)飼料的小鼠體內(nèi)發(fā)現(xiàn),，內(nèi)源性的抗氧化劑水平提高了,，致癌劑誘導(dǎo)的氧化損傷標(biāo)志物水平減少了，小鼠防御致癌劑損傷的能力有所提升,。
研究員根據(jù)這一結(jié)果猜測可可粉的預(yù)防癌癥發(fā)生的作用可能與阻斷細胞增殖過程中的信號轉(zhuǎn)導(dǎo)途徑有關(guān),。用含可可粉的飼料喂養(yǎng)動物后，動物體內(nèi)明顯出現(xiàn)細胞凋亡或細胞程序性死亡加劇現(xiàn)象,，這有可能是可可粉抑制癌癥發(fā)生的化學(xué)預(yù)防機制,。但研究中未明確到底是可可粉中的哪種生物活性化合物起到了抑癌的化學(xué)預(yù)防作用。（生物谷Bioon.com）
doi:10.1002/mnfr.201100363
PMC:
PMID:
Cocoa-rich diet prevents azoxymethane-induced colonic preneoplastic lesions in rats by restraining oxidative stress and cell proliferation and inducing apoptosis
Ildefonso Rodríguez-Ramiro1, Sonia Ramos1, Elvira López-Oliva2, Angel Agis-Torres2, Miren Gómez-Juaristi1, Raquel Mateos1, Laura Bravo1, Luis Goya1, María ángeles Martín1,3,*
Cocoa is a rich source of bioactive compounds with potential chemopreventive ability but up to date its effectiveness in animal models of colon carcinogenesis has not been addressed. Herein, we investigated the in vivo effect of a cocoa-rich diet in the prevention of azoxymethane (AOM)-induced colon cancer and the mechanisms involved. Our results showed that cocoa feeding significantly reduced AOM-induced colonic aberrant crypt foci formation and crypt multiplicity. Oxidative imbalance in colon tissues seems to be prevented by cocoa as indicated by reduced oxidation markers levels and increased enzymatic and non-enzymatic endogenous defences. Cocoa-rich diet also exhibited antiproliferative effects by decreasing the levels of extracellular regulated kinases, protein kinase B and cyclin D1 together with pro-apoptotic effects evidenced by reduced Bcl-xL levels and increased Bax levels and caspase-3 activity. Our findings provide the first in vivo evidence that a cocoa-rich diet may inhibit the early stage of colon carcinogenesis probably by preventing oxidative stress and cell proliferation and by inducing apoptosis.
