Hawthorn Extract Alleviates Atherosclerosis through Regulating Inflammation and Apoptosis Related Factors: An Experimental Study.

OBJECTIVE: To determine the effects of hawthorn extract on serum lipid levels, pathological changes in aortic atherosclerosis plaque, inflammatory factors, and apoptosis-related protein and mRNA expression in apolipoprotein E gene knockout (ApoE-/- ) mice.

METHODS: Thirty-six ApoE-/- mice were fed with a high-fat diet starting at the age of 8 weeks. Mice were randomly divided into 3 groups by a random number table including model group, hawthorn extract group, and simvastatin group, 12 mice in each group. Twelve 8-week-old C57BL/6 mice were fed a basic diet and served as control. The mice in the control and model groups were administered 0.2 mL saline daily, the mice in the hawthorn extract and simvastatin groups were administered with 50 mg/kg hawthorn extract or 5 mg/kg simvastatin daily for 16 weeks. After 16 weeks, plasma lipids including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were determined by an enzymatic assay. Aortic atherosclerotic lesions were observed by light microscopy, scanning and transmission electron microscopy, respectively. Plasma levels of monocyte chemoattractant protein-1 (MCP-1), interleukin-1β (IL-1β), adiponectin (APN), and hypersensitive C-reactive protein (hs-CRP) were measured by enzyme-linked immunosorbent assay (ELISA). Protein and mRNA expressions of Bax and Bcl-2 in the aorta were assessed by Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR), respectively.

RESULTS: Compared to the control group, the plasma levels of TC, TG and LDL-C were significantly increased and HDL-C were significantly decreased in the model group (P<0.01). Compared to the model group, treatment with hawthorn extract significantly decreased the plasma levels of TC, TG, and LDL-C and increased the plasma level of HDL-C in ApoE-/- mice (P<0.01). The levels of MCP-1, IL-1ß, and hs-CRP in the model group were significantly increased and APN was significantly decreased compared with the control group (P<0.01). Compared to the model group, treatment with hawthorn extract decreased the levels of MCP-1, IL-1ß, and hs-CRP and increased the APN level (P<0.01). Compared to the control group, the protein and mRNA expression of Bax in the model group were significantly increased and the expression of Bcl-2 was significantly decreased (P<0.01). Hawthorn extract also reduced the protein and mRNA expression of Bax and increased the Bcl-2 expression in the aorta (P<0.01).

CONCLUSION: Hawthorn extract has anti-atherosclerosis and stabilizing unstable plaque effects. The mechanism may be related to the inflflammation and apoptosis signaling pathways.