Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.
Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
Vet Clin Pathol. 2020 Sep;49(3):417-427. doi: 10.1111/vcp.12895. Epub 2020 Sep 23.
Lipid accumulation disorders, such as atherosclerosis and hepatic lipidosis, are common in psittacine birds and associated with various dyslipidemias. Gel-permeation high-performance liquid chromatography (GP-HPLC) is a reference method for advanced lipoprotein profiling based on particle size separation, followed by an analysis of lipid contents.
The objectives were to (a) characterize Quaker parrot lipoproteins using a commercial GP-HPLC method (Liposearch panel), and (b) obtain preliminary information on the reliability of the Friedewald formula for low-density lipoprotein-cholesterol (LDL-C) measurements.
Plasma samples were collected from 12 fasted healthy Quaker parrots. Cholesterol concentrations, triglyceride concentrations, particle sizes, and particle numbers were determined by GP-HPLC for four classes and 20 sub-fractions of lipoproteins. The LDL-C concentrations obtained using the Friedewald formula and direct measurements were compared with Bland-Altman plots. Alternate formulas were determined using multiple linear regression.
High-density lipoprotein (HDL) was the predominant lipoprotein in Quaker parrots, and most particles were of medium-to-small sizes belonging to two sub-fractions (average size, 10.6 nm). LDL was the second most common lipoprotein and included large-to-small particles belonging to three sub-fractions (average size, 24.9 nm). Very-low-density lipoproteins (VLDL) and portomicrons were present in low concentrations. The Friedewald formula underestimated LDL-C concentrations with a significant bias of 0.44 mmol/L. An alternate formula was proposed: LDL-C = 0.75*Non-HDL-C.
GP-HPLC allowed unprecedented characterization of plasma lipoproteins in Quaker parrots. Characterizing psittacine lipoprotein is useful for validation and interpretation of routine clinical tests as well as for use in epidemiologic and experimental research on psittacine lipid accumulation disorders.
脂质蓄积紊乱，如动脉粥样硬化和肝脂质沉积症，在鹦鹉中很常见，并与各种血脂异常有关。凝胶渗透高效液相色谱（GP-HPLC）是一种基于粒径分离的先进脂蛋白分析的参考方法，随后对脂质含量进行分析。
本研究旨在（a）使用商业 GP-HPLC 方法（Liposearch 试剂盒）对和尚鹦鹉的脂蛋白进行特征分析，（b）初步了解 Friedewald 公式用于测定低密度脂蛋白胆固醇（LDL-C）的可靠性。
采集 12 只禁食的健康和尚鹦鹉的血浆样本。采用 GP-HPLC 对胆固醇浓度、甘油三酯浓度、颗粒大小和颗粒数量进行分析，以确定脂蛋白的四个类别和 20 个亚类。用弗里德瓦尔德公式和直接测量法获得的 LDL-C 浓度用 Bland-Altman 图进行比较。用多元线性回归法确定替代公式。
高密度脂蛋白（HDL）是和尚鹦鹉中最主要的脂蛋白，大多数颗粒属于中小粒径的两个亚类（平均粒径为 10.6nm）。LDL 是第二常见的脂蛋白，包括大至小粒径的三个亚类（平均粒径为 24.9nm）。极低密度脂蛋白（VLDL）和前白蛋白存在于低浓度。Friedewald 公式低估了 LDL-C 浓度，存在 0.44mmol/L 的显著偏差。提出了一个替代公式：LDL-C=0.75*Non-HDL-C。
GP-HPLC 能够对和尚鹦鹉的血浆脂蛋白进行前所未有的特征分析。对鹦鹉脂蛋白进行特征分析，有助于验证和解释常规临床检测，也有助于对鹦鹉脂质蓄积紊乱的流行病学和实验研究。
