Antihyperlipidaemic effect of triterpenic acid-enriched fraction from <i>Cyclocarya paliurus</i> leaves in hyperlipidaemic rats

<p><b>Context:</b><i>Cyclocarya paliurus</i> (Batal) Iljinskaja (Juglandaceae) is an edible and medicinal plant; the leaves are used in Chinese folkloric medicine to treat dyslipidaemia and diabetes.</p> <p><b>Objective:</b> This study evaluates the antihyperlipidaemic potential of the triterpenic acid-enriched fraction (TAE) from <i>C. paliurus</i> and the underlying mechanism.</p> <p><b>Materials and methods:</b> The hyperlipidaemic rats were induced by high fat diet for 6 weeks. After oral administration of TAE (200 and 400 mg/kg), the neutral fraction (150 and 300 mg/kg) and statin (4 mg/kg) to the hyperlipidaemic rats for 4 weeks, lipid profile and apolipoprotein (apoB48) level in plasma, and the expression levels of apoB48, microsomal triglyceride transfer protein (MTP), phosphorylation of mitogen-activated protein kinase (MAPK) and tumour necrosis factor α (TNF-α) in intestine were examined. The main constituents in the TAE were identified by HPLC-MS.</p> <p><b>Results:</b> TAE administration (400 mg/kg) decreased the levels of atherogenic lipids in serum and liver (<i>p</i> < 0.05) and increased serum high-density lipoprotein cholesterol by 19.7%. Furthermore, TAE treatment (200 and 400 mg/kg) decreased plasma apoB48 level by 15.3 and 19.5%, downregulated intestinal apoB48 and MTP expression levels (<i>p</i> < 0.05), and inhibited TNF-α expression by 36.2 and 56.2% and the phosphorylation level of MAPK by 8.8 and 13.2%, respectively. HPLC analysis revealed the presence of pentacyclic- and tetracyclic-triterpene acids in TAE.</p> <p><b>Conclusion and discussion:</b> These findings suggested that TAE possessed antihyperlipidaemic activity partially involved in the inhibitory effect on apoB48 overproduction, which may provide evidence about its potential role in ameliorating dyslipidaemia.</p