Department of Public Health and Caring Sciences/Clinical Nutrition and Metabolism, Uppsala University, Uppsala Science Park, 75185 Uppsala, Sweden.
Diabetes Res Clin Pract. 2010 Mar;87(3):379-84. doi: 10.1016/j.diabres.2009.11.019.
To investigate the relationships of serum fatty acid (FA) composition and estimated desaturase activities with the liver fat marker alanine aminotransferase (ALT).
546 Swedish elderly men of a population-based cohort participated in this cross-sectional study. FA composition was assessed in serum cholesterol esters to determine dietary fat quality (e.g. linoleic) and desaturation products (e.g. dihomo-gamma-linolenic acid). Desaturase indices, including stearoyl coenzymeA desaturase-1 (SCD-1), were calculated by FA product-to-precursor ratios.
In linear regression analyses adjusting for lifestyle, abdominal obesity and insulin sensitivity, the dietary biomarker linoleic acid (n-6), but not n-3 FAs, was inversely related to ALT. Desaturation products including palmitoleic, oleic, gamma-linolenic and dihomo-gamma-linolenic acids, and Delta6-desaturase and SCD-1 indices were directly related to ALT (all p<0.05). After further adjustment for factors previously linked to fatty liver (i.e. serum lipids, adiponectin concentrations), SCD-1 index (p=0.004) and insulin resistance (p<0.0001) were independent determinants of ALT activity, whereas waist circumference, triglycerides, non-esterified FA and adiponectin were not.
A low dietary intake of linoleic acid and elevated SCD-1 index may contribute to higher ALT activity in elderly men, even independently of obesity and insulin resistance.
研究血清脂肪酸（FA）组成和估计的去饱和酶活性与肝脏脂肪标志物丙氨酸氨基转移酶（ALT）之间的关系。
本横断面研究纳入了 546 名瑞典老年男性的人群队列。通过血清胆固醇酯来评估 FA 组成，以确定膳食脂肪质量（如亚油酸）和去饱和产物（如二高γ-亚麻酸）。通过 FA 产物与前体的比值来计算去饱和酶指数，包括硬脂酰辅酶 A 去饱和酶-1（SCD-1）。
在调整生活方式、腹部肥胖和胰岛素敏感性的线性回归分析中，膳食生物标志物亚油酸（n-6）与 ALT 呈负相关，但 n-3 FA 则无此相关性。包括棕榈油酸、油酸、γ-亚麻酸和二高γ-亚麻酸在内的去饱和产物，以及 Delta6-去饱和酶和 SCD-1 指数与 ALT 呈正相关（均 P<0.05）。在进一步调整与脂肪肝相关的因素（即血清脂质、脂联素浓度）后，SCD-1 指数（P=0.004）和胰岛素抵抗（P<0.0001）是 ALT 活性的独立决定因素，而腰围、甘油三酯、非酯化 FA 和脂联素则不是。
老年人中，亚油酸的饮食摄入量低和 SCD-1 指数升高可能导致 ALT 活性升高，即使独立于肥胖和胰岛素抵抗。
