Turmeric and laurel aqueous extracts exhibit in vitro anti-atherosclerotic activity and in vivo hypolipidemic effects in a zebrafish model.

Culinary herbs and spices have been widely used for their hypoglycemic, lipid-lowering, and anti-inflammatory activities. This study examined the physiologic activity of hydrophilic components using extracts of turmeric or laurel leaf powder. Aqueous extracts of turmeric and laurel showed potent inhibitory activity against fructose-mediated glycation with antioxidant ability against low-density lipoprotein (LDL) oxidation and radical scavenging activity. The turmeric and laurel extracts had potent cholesteryl ester transfer protein (CETP) inhibitory ability (up to 23% and 40% inhibition, respectively) at a final concentration of 10 μg/mL. The turmeric and laurel extracts inhibited the cellular uptake of oxidized LDL into macrophages, which is the initial step in atherogenesis. For in vivo testing, zebrafish consumed a high cholesterol diet (HCD) (final concentration, 4% [wt/wt]) with or without turmeric or laurel powder (final concentration, 10% [wt/wt]). The turmeric and laurel groups had a 14% and 12% decrease, respectively, in the weight and height ratios compared to the HCD group. The plasma total cholesterol level was significantly lower in the turmeric and laurel groups (48% and 28% less, respectively, than in the HCD group). Plasma triglycerides were more markedly reduced in the turmeric and laurel groups than in the HCD group (68% and 56% less, respectively, than the HCD group). In conclusion, the hydrophilic extracts of turmeric and laurel potently suppressed the incidence of atherosclerosis via a strong antioxidant potential, prevention of apolipoprotein A-I glycation and LDL phagocytosis, and inhibition of CETP. Consumption of turmeric and laurel extracts exhibited hypolipidemic and antioxidant activities in a hypercholesterolemic zebrafish model.