School of Psychological Science, La Trobe University, Bundoora, VIC, Australia.
Nutr Res. 2010 May;30(5):366-73. doi: 10.1016/j.nutres.2010.05.001.
The influence of calorie restriction (CR) on increasing life span, enhancing immunocompetence, and reducing the incidence of age-related diseases is well established. Evidence points to the involvement of neuroendocrine alterations in these beneficial effects. Accordingly, we hypothesized that CR will result in significant alterations to the hormones investigated. Little attention has been directed toward ascertaining the doses of CR required to obtain such alterations and, indeed, whether a dose-response exists. Adult rats were subjected to 1 of 5 dietary regimens: control, CR12.5%, CR25%, CR37.5%, or CR50%. Rats were decapitated 3 weeks following the onset of restriction; and trunk blood was collected and assayed for concentrations of serum adrenocorticotropic hormone, corticosterone, and testosterone, as well as plasma concentrations of noradrenalin and adrenalin. No effect was found as a result of dietary manipulation for serum concentrations of adrenocorticotropic hormone. However, all doses of CR resulted in increased serum corticosterone in a dose-response trend. A dose-response was also observed for serum testosterone, with higher doses of CR associated with lower testosterone. Concentrations of noradrenalin were not found to be altered by any CR dose, although a trend toward a down-regulation at CR50% was observed. Plasma adrenalin displayed a biphasic distribution with reductions observed at CR25% and CR50%, although the down-regulations only attained statistical significance relative to the CR37.5% and not the control group. As well as reporting the effect of CR on multiple hormones within individual animals, these results go some way in determining the optimal levels of CR needed to induce neuroendocrinologic alterations.
热量限制（CR）对延长寿命、增强免疫功能和降低与年龄相关疾病的发病率的影响已得到充分证实。有证据表明，神经内分泌的改变参与了这些有益的影响。因此，我们假设 CR 将导致所研究的激素发生显著变化。人们很少关注获得这种改变所需的 CR 剂量，以及是否存在剂量反应。成年大鼠接受以下 5 种饮食方案之一：对照、CR12.5%、CR25%、CR37.5%或 CR50%。限制饮食 3 周后，大鼠被断头；采集 trunk 血液并检测血清促肾上腺皮质激素、皮质酮和睾酮浓度，以及血浆去甲肾上腺素和肾上腺素浓度。饮食处理对血清促肾上腺皮质激素浓度没有影响。然而，所有 CR 剂量都导致血清皮质酮呈剂量反应趋势增加。血清睾酮也呈现剂量反应，CR 剂量越高，睾酮越低。任何 CR 剂量都不会改变去甲肾上腺素的浓度，尽管在 CR50%时观察到下调的趋势。尽管在 CR25%和 CR50%时观察到降低，但血浆肾上腺素呈双相分布，下调仅相对于 CR37.5%和对照组具有统计学意义。这些结果不仅报告了 CR 对单个动物中多种激素的影响，而且在确定诱导神经内分泌改变所需的最佳 CR 水平方面也有所进展。
