Muscle Health Research Centre, School of Kinesiology and Health Science, York University , Toronto, Ontario , Canada.
J Appl Physiol (1985). 2017 Dec 1;123(6):1625-1634. doi: 10.1152/japplphysiol.01115.2016. Epub 2017 Aug 24.
Weight regain, adipose tissue growth, and insulin resistance can occur within days after the cessation of regular dieting and exercise. This phenomenon has been attributed, in part, to the actions of stress hormones as well as local and systemic inflammation. We investigated the effect of curcumin, a naturally occurring polyphenol known for its anti-inflammatory properties and inhibitory action on 11β-HSD1 activity, on preserving metabolic health and limiting adipose tissue growth following the cessation of daily exercise and caloric restriction (CR). Sprague-Dawley rats (6-7 wk old) underwent a "training" protocol of 24-h voluntary running wheel access and CR (15-20 g/day; ~50-65% of ad libitum intake) for 3 wk ("All Trained") or were sedentary and fed ad libitum ("Sed"). After 3 wk, All Trained were randomly divided into one group which was terminated immediately ("Trained"), and two detrained groups which had their wheels locked and were reintroduced to ad libitum feeding for 1 wk. The wheel locked groups received either a daily gavage of a placebo ("Detrained + Placebo") or curcumin (200 mg/kg) ("Detrained + Curcumin"). Cessation of daily CR and exercise caused an increase in body mass, as well as a 9- to 14-fold increase in epididymal, perirenal, and inguinal adipose tissue mass, all of which were attenuated by curcumin ( P < 0.05). Insulin area under the curve (AUC) during an oral glucose tolerance test, HOMA-IR, and C-reactive protein (CRP) were elevated 6-, 9-, and 2-fold, respectively, in the Detrained + Placebo group vs. the Trained group (all P < 0.05). Curcumin reduced insulin AUC, HOMA-IR, and CRP vs. the placebo group (all P < 0.05). Our results indicate that curcumin has a protective effect against weight regain and impaired metabolic control following a successful period of weight loss through diet and exercise, perhaps via inhibition of glucocorticoid action and inflammation. NEW & NOTEWORTHY Weight regain after dieting and exercise is a common phenomenon plaguing many individuals. The biological mechanisms underlying weight regain are incompletely understood and are likely multifactorial. In this paper, we examined the metabolic implications of curcumin, a compound known for its anti-inflammatory properties and inhibitory action on the enzyme 11β-HSD1, in a rodent model of adiposity rebound after the cessation of diet and exercise.
体重反弹、脂肪组织生长和胰岛素抵抗在停止常规节食和运动后几天内就会发生。这种现象部分归因于应激激素以及局部和全身炎症的作用。我们研究了姜黄素的作用，姜黄素是一种天然存在的多酚，具有抗炎特性，并能抑制 11β-HSD1 的活性，它可以防止代谢健康受损并限制脂肪组织生长，这种作用是在停止每日运动和热量限制（CR）后产生的。6-7 周大的 Sprague-Dawley 大鼠（SD 大鼠）接受了 24 小时自由轮式跑步访问和 CR（15-20 g/天；约 50-65%的自由进食量）的“训练”方案 3 周（“全部训练”），或保持静止并自由进食（“静止”）。3 周后，所有接受训练的大鼠被随机分为一组，立即终止（“训练”），另外两组的轮子被锁定，并重新引入自由进食 1 周。锁定轮子的两组分别接受每日灌胃安慰剂（“未训练+安慰剂”）或姜黄素（200mg/kg）（“未训练+姜黄素”）。停止每日 CR 和运动导致体重增加，附睾、肾周和腹股沟脂肪组织质量增加 9-14 倍，所有这些都被姜黄素减弱（P<0.05）。口服葡萄糖耐量试验期间的胰岛素曲线下面积（AUC）、HOMA-IR 和 C 反应蛋白（CRP）在 Detrained + Placebo 组分别比训练组升高 6 倍、9 倍和 2 倍（均 P<0.05）。与安慰剂组相比，姜黄素降低了胰岛素 AUC、HOMA-IR 和 CRP（均 P<0.05）。我们的结果表明，姜黄素对节食和运动减肥成功后的体重反弹和代谢控制受损具有保护作用，这可能是通过抑制糖皮质激素的作用和炎症来实现的。新的和值得注意的是：节食和运动后的体重反弹是困扰许多人的常见现象。体重反弹的生物学机制尚不完全清楚，可能是多因素的。在本文中，我们研究了姜黄素在节食和运动停止后肥胖反弹的啮齿动物模型中的代谢意义，姜黄素是一种已知具有抗炎特性和抑制 11β-HSD1 活性的化合物。
