| [Objective]:A mouse model of colorectal cancer(CRC)with accumulation of damp heat was constructed,and fecal microbiota transplantation(FMT)was used for treatment.By further measuring various indicators of the experimental mice,the intervention effect of FMT on the model mice was verified.The therapeutic effect of FMT on the colorectal cancer mice of damp-heat accumulation type provides a reference for the treatment and efficacy mechanism of CRC.[Method]:40 MC38 mice were randomly divided into blank group(10 mice)and model group(30 mice).The blank group was used as a control and provided with fresh feces for making fecal bacteria liquid;the model group was fed with high sugar and high fat +high temperature and high humidity.The method of environment + MC38 cell injection was used to prepare the CRC mouse model with accumulation of damp heat.The 30 model mice that were successfully established were randomly divided into saline group,5-FU group and FMT group,10 mice in each group,and were given saline gavage,5-FU intraperitoneal injection and FMT gavage treatment respectively.The body weight of the mice and the tumor volume were recorded during the administration period and during the treatment period;after the treatment,the eye blood of the model mice was collected for ELISA detection;The immune organ index was calculated;the tumor bodies of the model mice were harvested and weighed to calculate the tumor inhibition rate;Western blot was used to detect the expression of TLR4 and NF-κB p65 proteins in the spleen tissue;expression in murine tumor tissue.[Result]:(1)After being fed with high-fat and high-sugar feed + high-temperature and high-humidity environment for 21 days,the mice in the model group showed weight loss,tiredness,decreased activity,dull hair,poor appetite,and fishy stools.Pus and blood in the stool.One week after the injection of MC38 cells,a hard mass of about 0.5 mm could be palpated under the skin of the mice in the model group.(2)When the model of CRC mice with accumulation of damp heat was completed,the body weight of the mice in the saline group,5-FU group and FMT group decreased significantly compared with the blank group;during the administration period,the body weight of the mice in each group increased.However,compared with the blank group,the mice in the saline group,5-FU group,and FMT group were all lighter;after administration,compared with the normal saline group,the mice in the FMT group and the 5-FU group gained weight.The tumor growth rate of the mice in the 5-FU group and the FMT group was slower.From the 14 th day after inoculation,the tumor volume of the mice in the 5-FU group and the FMT group was significantly smaller than that in the saline group;compared with the saline group,the 5-FU group The tumor weight of mice in the FMT group was significantly lower;the tumor inhibition rates of the FMT group and the 5-FU group were 47.186% and 69.481%,respectively.The expression of Ki67 in the tumor tissues of each group was detected by immunohistochemistry,and the expression area of positive cells in the slices was analyzed by Image J.The results are as follows: Compared with the blank group,the expression of Ki67 positive cells in the saline group was significantly increased;receiving FMT and After 5-FU treatment,the expression of Ki67 was down-regulated in both FMT group and 5-FU group.(3)The analysis of the immune organ index of the mice in each group showed that the spleen and thymus index of the mice in the saline group were significantly lower than those in the blank group;compared with the saline group,the two groups of mice treated with FMT and the positive drug 5-FU The spleen index and thymus index increased;ELISA detected the expressions of IL-2,IL-6,IFN-γand TNF-αin the serum of the mice in the blank group,the saline group,the 5-FU group and the FMT group,and found that the saline group The contents of IL-2,IL-6,IFN-γ and TNF-α were significantly up-regulated compared with the blank group;after FMT intervention,the expression of the above factors decreased.Although FMT did not restore the expression of the above factors to normal levels,it was different from 5.Compared with the-FU group,the down-regulation of IL-2,IL-6,IFN-γ and TNF-α in the FMT group was more obvious.(4)The protein expression levels of TLR4 and NF-κB p65 were detected by Western Blot,which showed that the expression of NF-κB p65 protein in the saline group was significantly up-regulated compared with the blank group;compared with the saline group,the FMT group and 5-FU The expression of NF-κB p65 protein in the FMT group decreased slightly;compared with the 5-FU group,the expression of NF-κB p65 in the FMT group was slightly higher.The expression of TLR4 protein also showed an obvious upward-regulated trend in the saline group.After receiving the intervention of FMT and 5-FU,the levels of TLR4 were significantly decreased,and the down-regulation effect of the 5-FU group was more obvious than that of the FMT group.[Conclusion]:(1)A mouse model of CRC with accumulation of damp-heat was successfully established by the method of "high-fat,high-sugar + high temperature and high humidity";(2)Ki67 is an indicator of tumor cell proliferation activity.The expression of Ki67 in FMT group mice was down-regulated,indicating that FMT can inhibit tumor cell proliferation and improve the general condition of tumor mice;(3)FMT can reduce the inflammatory response by inhibiting the production of IL-2,IL-6,IFN-γ,and TNF-α inflammatory factors,thereby reducing tissue damage caused by excessive immune response;(4)FMT can effectively inhibit the protein expression of TLR4 and NF-κ B p65,accelerate the apoptosis of damaged cells,and down-regulate the expression of oncogenic factors;(5)FMT has a good therapeutic effect on CRC model mice with accumulation of damp heat,and its mechanism may be related to FMT controlling inflammatory response,improving immune function and activating the transduction of TLR4/NF-κB signaling pathway. |
PDF Full Text Request