Effects Of Dendrobium Nobile Lindl. Alkaloids On Hyperlipidemia And Vessel Atherosclerosis In ApoE~-/~- Mice

Objective: To observe the Effects of Dendrobium nobile Lindl. Alkaloids(DNLA) on hyperlipidemia and vessel atherosclerosis in Apo E- /- mice.Methods: 50 male Apo E- /- mice and 10 male C57 mice as normal controls were randomly divided into model groups and treatment groups. Mice were adaptively fed the rodent chow for one week, and then fed rodent chow in the normal group while the model groups and treatment groups were fed with high-fat-diet. Divide the treatment groups into DNLA low, medium and high dose group(30, 60, 90 mg/kg), andsimvastatin positive control group(25 mg/kg). Mice were gavaged 2 times a day for 16 weeks. At the end of experiment,the orbital blood was collected and the serum was isolated. Then, serum triglyceride(TG), cholesterol, low-density lipoprotein cholesterol(ldl-c), high-density lipoprotein cholesterol(hdl-c)were measured by using the automatic biochemical instrument. Observe the vascular intimal plaques in mice with Ultrasound instrument, sample the specimens of blood vessels and observe the vascular tissue morphology by employing the HE Staining approach. Detect the vascular inflammation factors COX-2, IL-6, IL–1β and TNF-α protein expression levels by Western blot.Results: Compared with the model group, each DNLA treatment group had an increase of the lipid levels and the blood vessels plaques were stable in ultrasound observation. Vascular HE staining showed a significant formation of atherosclerotic plaque in the model mice and the use of different doses of DNLA in the treatment groups proved that DNLA can stabilize and control the development of artery atherosclerotic plaque development. Experiments also revealed that the vascular inflammation markers of COX-2, IL-6, IL–1β TNF-α in the model group were significantly higher than that of the blank group, whereas all these expressions were reduced after giving DNLA to the mice with different doses. Conclusion: DNLA can reduce the lipid levels of Apo E-/-mice and has certain functions in protecting blood vessels. The mechanism may be related to the inhibition of the production of inflammatory cytokines such as COX-2, IL-1β, IL-6 and TNF-α which can lower the protein level.DNLA can control inflammation and then further control and stabilize the formation of vascular plaque.