Regulation of HDL cholesterol metabolism and the impact of long‐term feeding of dietary jojoba oil and cholesterol on the development of atherosclerosis in New Zealand white rabbits: a foundational study (671.14)

Abstract

Jojoba oil has been shown to maintain high‐density lipoprotein (HDL) concentration in hypercholesterolemic New Zealand White (NZW) rabbits, suggesting that jojoba oil regulates HDL metabolism and has a protective effect against atherosclerosis, one of the leading causes of death worldwide. We thus hypothesized that jojoba oil decreases the development of atherosclerosis in NZW rabbits. As a preliminary study, five NZW rabbits were fed either a normal chow diet (N), or a normal diet supplemented with either 3% jojoba seed oil (J), 1% cholesterol (C), or 1% cholesterol + 3% jojoba seed oil (CJ) for 7 weeks; each diet group contained one rabbit, except the C‐fed group which contained two. During the study, serum lipoprotein cholesterol concentrations were monitored via enzymatic assays and gel electrophoresis. Liver function was examined via serum albumin measurements. Rabbit aortas were extracted and assessed for the development of atherosclerotic lesions. Results indicated that NZW rabbits responded to the experimental diets as shown in previous studies. N and J‐fed rabbits showed no change in their lipoprotein profiles. C‐ and CJ‐fed rabbits had a decrease in HDL concentration; however, the decrease was less in the CJ rabbits than the C rabbits. Serum albumin measurement indicated proper liver function. Unfortunately, none of the rabbits developed atherosclerotic lesions and the effects on dietary jojoba oil on atherosclerosis development could not be assessed in this study. Despite the negative results, this preliminary study allowed us to better understand what must be done in order to study the original question of interest. In future studies, we plan to ensure atherosclerotic lesion development by conducting a dose response study.