In Vitro Lipase, Cholesterol Esterase and Cholesterol Micellization Inhibitory Activities of Ceylon Cinnamon (Cinnamomum Zeylanicum Blume)

Abstract

Hyperlipidaemia is a group of metabolic disorders characterized by the elevated levels of serum triglycerides and cholesterol. It contributes significantly in pathogenesis of diabetes, obesity, hypertension and cardiovascular diseases. Hence, there is an imperative need for development of antilipidemic agents preferably from natural sources. Cinnamomum zeylanicum Blume is indigenous to Sri Lanka and used as a spice in several countries. According to some Sri Lankan traditional physicians the bark of this plant is claimed to possess antilipidemic effects by inhibition of lipid digestion and/or absorption. This study was initiated to investigate antilipidemic potential of Ceylon cinnamon in vitro. Ethanolic (95%) and 1:1 dichloromethane: methanol (DCM:M) brak extracts of Ceylon cinnamon were used in this study. Different concentrations of ethanolic and DCM:M bark extracts (anti-lipase: 3.75 - 600 ?g/ml, n = 3; cholesterol esterase: 3.125 - 100 ?g/ml, n = 3; cholesterol micellization: 0.25 - 1 mg/ml, n = 6) were used in testing of antilipidemic effects. The results revealed that both extracts possess moderate lipase inhibitory activity (ethanol bark IC50 301.09 ± 5.73 ?g/ml and DCM:M bark IC50 297.57 ± 11.78 ?g/ml), high cholesterol esterase inhibitory activity (ethanol bark IC50 30.62 ± 1.67 ?g/ml and DCM:M bark IC50 34.39 ± 0.91 ?g/ml) and moderate to high cholesterol micellization inhibitory activities (mean percentage inhibition of cholesterol solubility in micelles in ethanolic bark and DCM:M bark 98.09 ± 1.25 and 73.94 ± 1.95, at 1 mg/ml; 69.48 ± 1.99 and 62.15 ± 2.37 at 0.5 mg/ml and 49.48 ± 1.90 and 19.36 ± 4.57 at 0.25 mg/ml respectively). Further, anti-lipase and anti-cholesterol esterase activities were dose dependent. It is concluded that Ceylon cinnamon bark possess anti-lipase, cholesterol esterase and cholesterol micellization inhibitory activities. This is a novel finding having therapeutic potentials and indicates the potential of using bark as a functional food for hyperlipidaemia.