益生菌及布拉氏酵母菌对炎症相关结直肠癌小鼠模型肠道菌群的作用

Effects of probiotics and B.pastoris on intestinal flora in a mouse model of inflammation-related colorectal cancer

目的观察益生菌vs.L#3及布拉氏酵母菌对炎症相关结直肠癌小鼠模型肠道菌群的作用。方法选取购自广西医科大学实验动物中心,6~8周龄C57BL/6J雄性小鼠60只,依据随机数字表法分为4组,每组15只,各组小鼠适应性喂养1周后行后续实验。A组为空白对照组,其余3组均诱导炎症相关结直肠癌模型。B、C、D组分别给予饮用水、益生菌vs.L#3、布拉氏酵母菌灌胃。建模后12周处死小鼠,评估结肠大体成瘤情况,比较结直肠成瘤率、肿瘤数目和瘤负荷。检测并比较处理前及处死前粪便菌群及结肠黏膜菌群的变化,比较W0、W6、W12时各组疾病活动度(DAI)。多组间计量资料采用方差检验,多组间计数资料采用χ^2检验。结果C组小鼠的肿瘤数目(1.88±0.35)个和瘤负荷(0.63±0.07)cm均低于其余3组,D组小鼠的肿瘤数目(2.78±0.49)个和瘤负荷(1.11±0.32)cm均低于A组和B组,B组小鼠的肿瘤数目(3.83±0.82)个和瘤负荷(2.17±0.15)cm均低于A组的(7.67±1.88)个和(2.42±0.22)cm,差异有统计学意义(F=9.676、4.151,P<0.05)。A组和C组小鼠的W12粪便菌群(52.38±9.29、51.88±5.33)和黏膜菌群(98.76±41.88、98.57±30.45)均高于B组和D组,D组小鼠的W12粪便菌群(49.76±2.43)和黏膜菌群(97.08±22.45)均高于B组的(47.55±5.38)和(94.30±21.87),差异统计学有意义(F=6.035、8.427,P<0.05)。A组(69396.55±4847.28)和C组(68245.38±10445.98)小鼠的W12粪便菌群操作分类单位(OTU)丰度均低于B组(77722.38±8459.91)和D组(74289.67±5243.38),C组(50717.62±21611.79)和D组(38759.70±24934.91)小鼠的W12黏膜菌群OTU丰度均低于A组(61601.08±12431.97)和B组(56976.46±22822.81),且D组低于C组,差异有统计学意义(F=8.036、4.538,P<0.05)。C组(7.12±0.64、6.75±0.46)和D组(7.25±0.70、6.88±0.64)小鼠W6和W12 DAI均低于B组的(8.25±1.48、7.62±1.15),差异统计学有意义(F=7.037、5.365,P<0.05)。结论益生菌vs.L#3及布拉氏酵母菌均可影响炎症相关结直肠癌小鼠的肠道菌群。较正常小鼠,益生菌vs.L#3可增加粪便及黏膜菌群活性,抑制菌群多样性,布拉氏酵母菌可增加粪便及黏膜菌群多样性,两者均具有较佳的肠道菌群调节作用,抑制炎癌转化过程。

Objective To observe the effects of probiotics vs.L#3 and Bradyrhizobium on intestinal flora in mice with inflammation-related colorectal cancer.Methods Sixty C57BL/6J male mice aged 6-8 weeks were selected and divided into 4 groups according to the random number table method.Each group consisted of 15 mice.The mice in each group were adaptively fed for 1 week for subsequent experiments.Group A was a blank control group,and in the rest three groups,inflammation-related colorectal cancer models were induced.Groups B,C,and D were administered with drinking water,probiotics vs.L#3,and B.blazei,respectively.Mice were sacrificed 12 weeks after modelling,and colonic tumor formation was evaluated to compare the colorectal tumor formation rate,tumor number,and tumor burden.Changes in fecal flora and colonic mucosa before treatment and before sacrifice were detected and compared,and disease activity(DAI)of each group was compared at W0,W6,and W12.Results The number of tumors in group C mice(1.88±0.35)and tumor burden(0.63±0.07)cm were lower than those in the other three groups.The number of tumors in group D mice(2.78±0.49)and tumor burden(1.11±0.32).cm were lower than those in group A and B,the number of tumors in group B mice(3.83±0.82)and tumor burden(2.17±0.15)cm were lower than those in group A(7.67±1.88)and(2.42±0.22)cm,the difference was statistically significant(F=9.676,4.151,P<0.05).The W12 fecal flora(52.38±9.29,51.88±5.33)and mucosal flora(98.76±41.88,98.57±30.45)of the mice in group A and C were higher than those in group B and group D,and the mice in group D had W12 stool The flora(49.76±2.43)and mucosal flora(97.08±22.45)were higher than those in group B(47.55±5.38)and(94.30±21.87),and the differences were statistically significant(F=6.035,8.427,P<0.05).The W12 fecal flora OTU abundance of mice in group A(69396.55±4847.28)and group C(68245.38±10445.98)was lower than those in group B(77722.38±8459.91)and group D(74289.67±5243.38)and group C(50717.62±21611.79)And group D(38759.70±24934.91)W12 mucosal flora OTU abundance were lower than group A(61601.08±12431.97)and group B(56976.46±22822.81),and group D was lower than group C,the difference was statistically significant Significance(F=8.036,4.538,P<0.05).The W6 and W12 DAI in group C(7.12±0.64,6.75±0.46)and group D(7.25±0.70,6.88±0.64)were lower than those in group B(8.25±1.48,7.62±1.15),and the difference was statistically significant.(F=7.037,5.365,P<0.05).Conclusion Probiotics vs.L#3 and Bradyrhizobium can influence the intestinal flora of mice with inflammation-related colorectal cancer.As compared with normal mice,probiotic vs.L#3 can increase the activity of fecal and mucosal flora and inhibit the diversity of bacteria.Brassica can increase the diversity of feces and mucosal flora.Both of them can effectgively regulate the intestinal bacteria and inhibit the transformation process of inflammation.