高油飲食中補充不同劑量共軛亞麻油酸對小鼠體脂蓄積的影響

Effects of different dosages of dietary conjugated linoleic acid on fat accumulation in mice fed a high-fat diet

陳沛彤(Pei-Tung Chen)

指導教授 ： 簡怡雯

臺北醫學大學/公共衛生暨營養學院/保健營養學研究所/碩士(2012年)

https://doi.org/10.6831/TMU.2012.00120

摘要

共軛亞麻油酸（conjugated linoleic acid, CLA）為天然共軛脂肪酸，存在於反芻動物的肉與乳脂肪中，近年來被認為具有降低動物與人體脂肪蓄積的功效。本實驗採用40隻3週齡的ICR小鼠，隨機分為4組，分別為給予AIN-93G的正常飲食組 (C組)、油脂比例為20% (wt/wt) 的高油飲食組 (HF)、高油飲食中添加0.5% (wt/wt) 的1倍劑量CLA (1x) 組與添加2.5% (wt/wt) 的5倍劑量CLA (5x) 組。實驗期間每週固定測量其體重變化與攝食情形，飼養8週後予以犧牲。結果顯示CLA (1x)組的腓腸肌重顯著較高，而CLA (5x) 則可以顯著降低體重增加量、血清三酸甘油酯濃度、血清游離脂肪酸濃度與脂肪激素瘦體素的濃度並且增加副睪脂肪脂蛋白脂解酶與肝臟脂肪氧化酵素carnitine palmitoyltransferase-I (CPT-I) 活性；此外兩組添加CLA的組別與HF組相比皆有顯著較低副睪白色脂肪組織重、肝臟脂肪合成酵素acetyl CoA carboxylase (ACC) 活性以及較高血清高密度脂蛋白膽固醇濃度；雖有較高肝臟重但不影響肝臟脂質濃度與肝功能。因此，本研究認為高油飲食中添加CLA可藉由影響脂肪代謝酵素，達到預防小鼠體脂肪蓄積的作用；此外也可藉由提高血液中高密度脂蛋白膽固醇濃度並降低三酸甘油酯以及血清游離脂肪酸濃度，達到改善脂質代謝的效果且具劑量效應。
關鍵字：共軛亞麻油酸、高油飲食、脂質代謝、體脂肪、脂質代謝酵素

關鍵字

共軛亞麻油酸、高油飲食、脂質代謝、體脂肪、脂質代謝酵素

並列摘要

Obesity is associated with a high risk of developing diabetes and cardiovascular disease. Therefore, management of body weight and obesity remains as an important priority. The aim of this study was to investigate the effects of different dosage of CLA at high-fat (HF) levels on blood parameters, fatty acid oxidation and potential impacts on prevention of body fat deposition. Growing mice were fed a control diet, an HF diet containing 20% soybean oil, or two different dosages of CLA oil supplementation, including an HF diet containing 0.5% CLA (CLA(1x)) and 2.5% CLA (CLA(5x)). As a result of 8 weeks' dietary intervention, CLA (1x) increased muscles mass and CLA (5x) significantly reduced weight gain, serum levels of triglyceride, free fatty acid and leptin, increased epididymal fat lipoprotein lipase and carnitine palmitoyltransferase-I activity. In addition, both the CLA groups showed reduced fat mass, acetyl CoA carboxylase activity, and increased serum high-density lipoprotein cholesterol levels. Overall, some positive aspects were found in CLA group. Even the fat reduction is nutritionally important for weight control; CLA mediates the potential effects could prevent body fat deposition, improve fatty acid oxidation and promote lipid metabolism, and have dose effect.
Key words: CLA, high-fat diet, body fat deposition, lipid metabolism, fatty acid oxidation

並列關鍵字

CLA, high-fat diet, body fat deposition, lipid metabolism, fatty acid oxidation

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