The Effect Of Different Types Of Dietary Fatty Acids On Plasma Fatty Acid Profiles

objective High fat diet is a risk factor for the development of various diseases.The purpose of this study is to investigate the effects of different dietary fatty acids on plasma fatty acid profiles in normal and tumor-bearing mice,and to study whether the metabolism of tumor affects plasma fatty acid profile.Normal mice and those with pancreatic carcinoma cells were used as the research models.to observe the effects of high fat diets rich in saturated fatty acid(SFA),monounsaturated fatty acid(MUFA),n-6 polyunsaturated fatty acids(n-6PUFA)and n-3 polyunsaturated fatty acids(n-3PUFA)of plasma fatty acid profile.The effects of different fatty acids on the fatty acid in plasma were compared between normal mice and tumor-bearing mice.The interaction between fatty acid metabolism and tumor metabolism was also discussed.Method Part One Male Balb/C mice were randomly divided into normal control(NC)group,SFA group,MUFA group,n-6PUFA group and n-3PUFA group.The control group were fed with normal diet and the others were fed with high fat diets.Containing 20%(mass ratio)of fat.The fat in the four high fat diets were rich in SFA(representative fatty acids were laurel acid C12:0 and myristic acid C14:0),MUFA(representative fatty acid was oleic acid C18:1),n-6PUFA(representative fatty acid was linoleic acid C18:2)and n-3PUFA(epresentative fatty acid was linolenic acid C18: 3).During the experiment,we observed the general conditions of mice.And recorded the changes of food intake and body weight.Each group of mice was fed with the corresponding experimental food for 10 days,and then plasma samples were collected at the end of the experiment.Part Two Male Balb/C mice were randomly divided into normal control(NC)group,SFA group,MUFA group,n-6PUFA group and n-3PUFA group.The only difference between the first part and this part was that the experiment ended after six weeks of feeding for this time.Part Three Male Balb/C nude mice were randomly divided into 6 groups.A piece of tumor tissue made of Mia Pa Ca2 cells was transplanted in 5 groups of mice subcutaneously,the remaining group were set as a tumor-free control group.One week after the subcutaneous transplantation,five groups of tumor carriers were fed for 7 weeks with four high fat diets and the normal diet,respectively.The tumor-free mice were also fed with normal diet.The general condition of the nude mice was observed during the experiment,and the change of food intake and weight was recorded,and the specimen was collected at the end of the experiment.Result 1.After administration of high fat diets for 10 days in normal mice,the changes of plasma fatty acid were as follows:(1)content of C11:0 in SFA group increased(P<0.05),and palmitic acid(C16:0)and stearic acid(C18:0)content also increased in the same group,but lauric acid(C12:0)content decreased in SFA group(P<0.05).(2)the content of oleic acid(C18:1)increased in MUFA group(P<0.01).(3)the content of linoleic acid(C18:2)and arachidonic acid(C20:4)increased significantly in the n-6PUFA group(P<0.01).(4)the content of C18:3 increased in the n-3PUFA group(P<0.01).2.After administration of high fat diets for 6 weeks in normal mice,the changes of plasma fatty acid were as follows:(1)content of C12:0 and C14:0 were higher in the SFA group(P<0.01).(2)the content of oleic acid(C18:1)increased in MUFA group(P<0.01).(3)the content of C18:2 did not change significantly in the n-6PUFA group(P>0.05).(4)the content of C18:3 increased in the n-3PUFA group(P<0.01).3.After administration of high fat diets for 7 weeks in tumour-bearing mice,the changes of plasma fatty acids were as follows:(1)the contents of C12:0 and C14:0 increased in SFA group(P<0.01).(2)the contents of C18:1 increased in MUFA group(P<0.01).(2)the content of C18:2 had an increase trend in the n-6PUFA group.(3)the content of C18:3 increased in n-3PUFA group(P<0.01).Conclusion 1.After short-term dietary intervention,the composition of fatty acids in plasma was consistent with the composition of fatty acids in the diet.After long-term intervention,the representative fatty acids in the n-6PUFA group did not increase.2.The response of the tumor-bearing mice to the experimental meal was largely the same as that of the non-tumor mice,but the n-6PUFA high fat meal could also increase the n-6PUFA in the plasma of the tumor-bearing mice.3.The effects of cancer cells on the metabolism of n-6PUFA lead to the difference in plasma n-6PUFA between tumor free and tumor carrying mice,which may help the diagnosis and treatment of cancer.