绿变大蒜的色素成分及抗肝癌活性

Pigment Composition and Anticancer Effect on Hepatoma Carcinoma of Greening Garlic

目的:探讨绿变大蒜两种色素提取物对肝癌的抑制作用。方法:以绿变大蒜为原料,用体积分数75%乙醇溶液冷浸提取,经AB-8大孔树脂柱层析分离得到蓝色素(blue pigments,BP)和黄色素(yellow pigments,YP)的粗提物,并采用噻唑蓝法考察其纯化物BP-1及YP-3对HepG2细胞的抑制增殖作用;同时建立H22荷瘤小鼠模型:将80只小鼠随机分为8组:模型组、阳性对照组(腹腔注射20 mg/kg环磷酰胺)和BP低(L-BP,灌胃75 mg/kg BP)、中(M-BP,灌胃150 mg/kg BP)、高剂量组(H-BP,灌胃300 mg/kg BP)以及YP低(L-YP,灌胃75 mg/kg YP)、中(M-YP,灌胃150 mg/kg YP)、高剂量组(H-YP,灌胃300 mg/kg YP),连续给药14 d。研究色素提取物对小鼠的肿瘤生长、免疫器官指数及水食效率(摄食效率、摄水效率)的影响。测定肝脏中超氧化物歧化酶、谷胱甘肽过氧化物酶、过氧化氢酶、谷丙转氨酶、谷草转氨酶活力和丙二醛(malondialdehyde,MDA)含量及血清中细胞因子、肿瘤坏死因子-α(tumor necrosis factor alpha,TNF-α)、白细胞介素-2(interleukin-2,IL-2)和血管内皮生长因子(vascular endothelial growth factor,VEGF)的水平;取小鼠的肿瘤组织进行病理学分析。结果:与模型组相比,给予BP和YP后,荷瘤小鼠的肿瘤体积显著变小(P<0.05),胸腺和脾脏指数显著升高(P<0.05),且肿瘤生长速率变缓,能一定程度改善H22荷瘤小鼠免疫功能及抑制肿瘤生长;同时,提高抗氧化酶活力、降低MDA含量,减少肝脏炎症的发生;与模型组相比,给药组的IL-2和TNF-α的表达水平都显著提高(P<0.05),VEGF的表达水平降低了63%左右。结论:绿变大蒜中的BP和YP具有一定的抗肝癌活性,为开发绿变大蒜功能食品提供了参考。

Objective:To investigate the inhibitory effect of two pigments extracted from greening garlic on hepatoma carcinoma.Methods:Green garlic was extracted with 75%cold ethanol and the crude extract was separated by AB-8 macroporous resin column chromatography to obtain blue pigment(BP)and yellow pigment(YP).The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide method was used to investigate the inhibitory effect of purified BP-1 and YP-3 on the proliferation of HepG2 cells.An H22 tumor-bearing mouse model was established and 80 H22 tumor-bearing mice were divided into 8 groups:model group,positive control group(cyclophosphamide,CTX,20 mg/kg),BP low-,middle-and high-dose groups(L-BP,M-BP,H-BP;75,150,300 mg/kg),and YP low-,middle-and high-dose groups(L-YP,M-YP,H-YP;75,150,300 mg/kg)for 14 days,with the aim to study the effects of the pigments on tumor growth,immune organ index,and water and food efficiency.The activities of superoxide dismutase,glutathione peroxidase,catalase,alanine aminotransferase,aspartate aminotransferase and malondialdehyde(MDA)content in liver and the levels of cytokines tumor necrosis factor alpha(TNF-α),interleukin-2(IL-2)and vascular endothelial growth factor(VEGF)in serum were measured.Pathological analysis of tumor tissues in mice was carried out.Results:Compared with the model group,the tumor volume in the BP and YP groups were significantly smaller(P<0.05)accompanied by a slower growth rate of transplanted tumors,and the thymus and spleen indexes were significantly increased(P<0.05),suggesting improved immune function and inhibited tumor growth in H22 tumor-bearing mice.Moreover,both pigments increased the activity of antioxidant enzymes,decreased the content of MDA,and consequently attenuated liver inflammation.Compared with the model group,the expression levels of IL-2 and TNF-αin the treatment groups were increased(P<0.05),and the expression level of VEGF was decreased by 63%.Conclusion:BP and YP from green garlic have anticancer activity on hepatoma carcinoma,which lays the foundation for the development of garlic-based functional foods.