Hypolipidemic Effects Of Eucommia Ulmoides Oliver Pollen In A High-fat Diet-induced Rat Model Of Hyperlipidemia

With the changes of the diet of modern humans,hyperlipidemia(HLP)has become a common chronic disease.If it cannot be effectively intervened,it will become an important factor that affecting human health and quality of life.Eucommia ulmoides Oliver is a genus of Eucommiaceae.E.ulmoides Oliver pollen is an important pollen resource in our country.It is very popular because of its large amount of active ingredients.The E.ulmoides Oliver male flower tea as a new health care product on the market,claims to have the effect of reducing hyperlipidemia,hypertension and high blood sugar,which is very popular and expensive.According to the literature search,E.ulmoides pollen is rich in flavonoids,polyphenols and other hypolipidemic and antioxidant components.But at present,there are few reports about E.ulmoides Oliver pollen reducing blood lipids,and there is no study about its related mechanism.Therefore,we choosed E.ulmoides Oliver pollen to give hyperlipidemic rats by intragastric administration,in order to observe the effect of E.ulmoides Oliver pollen on blood lipids and its mechanism.It aims to provide a theoretical basis for the further development and utilization of E.ulmoides Oliver pollen.The results are as follows1.Effects of E.ulmoides Oliver pollen on body weight and liver of hyperlipidemic ratsWe analyzed the changes of body weight and liver ratio of rats,the results showed that E.ulmoides Oliver pollen could effectively reduce the gain of weight in rats,but there was no significant difference,and the high dose group could reduce the liver ratio of rats(P < 0.05).There was no significant effect of E.ulmoides Oliver pollen on liver ratio in middle and low dose groups.The results of HE staining showed that,both in the high-dose E.ulmoides Oliver pollen group and lovastin group,the number of fat vacuoles in the liver of rats has been decreased,and the fat vacuoles also has been decreased in the middle-dose and low-dose E.ulmoides Oliver pollen groups.The content of liver index ALT,AST in serum was determined.The results showed that the high dose group of E.ulmoides Oliver pollen could reduce the content of ALT(P < 0.01),AST in serum of rats(P < 0.05),but there was no significant effect on it in middle dose group and low dose group.2.Effects of E.ulmoides Oliver pollen on serum lipid and antioxidant factors in rats with hyperlipidemiaThe high dose group of E.ulmoides Oliver pollen significantly decreased the content of TC(P < 0.001),TG(P < 0.01)and increased the content of HDL-C(P < 0.05),but had no significant effect on the content of LDL-C,and the middle and low dose groups had no significant effect on the level of blood lipid in serum of hyperlipidemic rats.It shows that E.ulmoides Oliver pollen has the effect of lowering blood lipids.High dose of E.ulmoides Oliver pollen could increase the content of SOD in serum,decrease the content of MDA and enhance the ability of antioxidation,but it had no significant effect on the content of GSH-PX.E.ulmoides Oliver pollen had no significant effect on the contents of the above three oxidation factors in middle and low dose groups.It shows that E.ulmoides Oliver pollen has enhanced antioxidant capacity3.The mechanism of E.ulmoides Oliver pollen lowering blood lipids in hyperlipidemia ratsThe results of Western blot detection showed that the protein expression of cholesterol synthesis related factors HMGCR(P < 0.01)and SREBP-2(P < 0.001)was decreased in the high dose group of E.ulmoides Oliver pollen.There was no significant difference in the protein expression of the above factors between the middle dose group and the low dose group in hyperlipidemia rats.The results of RT-PCR showed that the E.ulmoides Oliver pollen could down-regulate the expression of SREBP-2,HMGCR gene in high-dose group and middle-dose group(P < 0.05),but there was no significant effect on it in low-dose group.The results of immunohistochemistry showed that E.ulmoides Oliver pollen could reduce the positive expression of HMGCR(P<0.05),and it has a tendency to reduce the expression of ACAT2 on rat liver,but it is not significant.Conclusion: E.ulmoides Oliver pollen can slow down the weight gain of rats,reduce the liver ratio,improve the ability of antioxidation,down-regulate the expression of factors related to cholesterol synthesis and metabolism,and effectively reduce the level of blood lipids in serum of hyperlipidemic rats,protect the liver.