Department of Medicine, Faculty of Medicine, Cardiology Axis of the Institut Universitaire de Cardiologie et de Pneumologie de Québec (Hôpital Laval) and Metabolism, Vascular and Renal Health Axis, Laval University Hospital Research Center, Quebec, Canada G1V 4G2.
Metabolism. 2011 Aug;60(8):1122-30. doi: 10.1016/j.metabol.2010.12.005. Epub 2011 Feb 8.
Mounting evidence suggests that the benefits of fish consumption are not limited to the well-appreciated effects of omega-3 fatty acids. We previously demonstrated that cod protein protects against the development of diet-induced insulin resistance. The goal of this study was to determine whether other fish protein sources present similar beneficial effects. Rats were fed a high-fat, high-sucrose diet containing protein from casein or fish proteins from bonito, herring, mackerel, or salmon. After 28 days, oral glucose tolerance tests or hyperinsulinemic-euglycemic clamps were performed; and tissues and plasma were harvested for biochemical analyses. Despite equal energy intake among all groups, the salmon-protein-fed group presented significantly lower weight gain that was associated with reduced fat accrual in epididymal white adipose tissue. Although this reduction in visceral adiposity was not associated with improved glucose tolerance, we found that whole-body insulin sensitivity for glucose metabolism was improved using the very sensitive hyperinsulinemic-euglycemic clamp technique. Importantly, expression of both tumor necrosis factor-α and interleukin-6 was reduced in visceral adipose tissue of all fish-protein-fed groups when compared with the casein-fed control group, suggesting that fish proteins carry anti-inflammatory properties that may protect against obesity-linked metabolic complications. Interestingly, consumption of the salmon protein diet was also found to raise circulating salmon calcitonin levels, which may underlie the reduction of weight gain in these rats. These data suggest that not all fish protein sources exert the same beneficial properties on the metabolic syndrome, although anti-inflammatory actions appear to be common.
越来越多的证据表明，鱼类消费的益处不仅限于人们熟知的ω-3 脂肪酸的作用。我们之前的研究表明，鳕鱼蛋白可预防饮食诱导的胰岛素抵抗。本研究旨在确定其他鱼类蛋白源是否具有类似的有益作用。实验用含酪蛋白或鲣鱼、鲱鱼、鲭鱼或三文鱼蛋白的高脂肪、高蔗糖饮食喂养大鼠。28 天后，进行口服葡萄糖耐量试验或高胰岛素-正常血糖钳夹试验；采集组织和血浆用于生化分析。尽管所有组的能量摄入相等，但三文鱼蛋白组的体重增加明显较低，这与附睾白色脂肪组织中脂肪积累减少有关。尽管内脏脂肪减少与改善葡萄糖耐量无关，但我们发现，使用非常敏感的高胰岛素-正常血糖钳夹技术，整体葡萄糖代谢的胰岛素敏感性得到改善。重要的是，与酪蛋白喂养的对照组相比，所有鱼类蛋白喂养组的内脏脂肪组织中肿瘤坏死因子-α和白细胞介素-6 的表达均降低，表明鱼类蛋白具有抗炎特性，可预防肥胖相关的代谢并发症。有趣的是，还发现食用三文鱼蛋白饮食会提高循环三文鱼降钙素水平，这可能是这些大鼠体重增加减少的原因。这些数据表明，并非所有鱼类蛋白源对代谢综合征都具有相同的有益作用，尽管抗炎作用似乎是常见的。
