男性老年人认知障碍的激素途径。
The hormonal pathway to cognitive impairment in older men.
机构信息
Department of Internal Medicine and Biomedical Sciences, Section of Geriatrics, University of Parma, Parma, Italy.
出版信息
J Nutr Health Aging. 2012 Jan;16(1):40-54. doi: 10.1007/s12603-012-0002-7.
In older men there is a multiple hormonal dysregulation with a relative prevalence of catabolic hormones such as thyroid hormones and cortisol and a decline in anabolic hormones such as dehydroepiandrosterone sulphate, testosterone and insulin like growth factor 1 levels. Many studies suggest that this catabolic milieu is an important predictor of frailty and mortality in older persons. There is a close relationship between frailty and cognitive impairment with studies suggesting that development of frailty is consequence of cognitive impairment and others pointing out that physical frailty is a determinant of cognitive decline. Decline in cognitive function, typically memory, is a major symptom of dementia. The "preclinical phase" of cognitive impairment occurs many years before the onset of dementia. The identification of relevant modifiable factors, including the hormonal dysregulation, may lead to therapeutic strategies for preventing the cognitive dysfunction. There are several mechanisms by which anabolic hormones play a role in neuroprotection and neuromodulation. These hormones facilitate recovery after brain injury and attenuate the neuronal loss. In contrast, elevated thyroid hormones may increase oxidative stress and apoptosis, leading to neuronal damage or death. In this mini review we will address the relationship between low levels of anabolic hormones, changes in thyroid hormones and cognitive function in older men. Then, giving the contradictory data of the literature and the multi-factorial origin of dementia, we will introduce the hypothesis of multiple hormonal derangement as a better determinant of cognitive decline in older men.
在老年男性中,存在多种激素失调,其中分解代谢激素(如甲状腺激素和皮质醇)相对较多,合成代谢激素(如硫酸脱氢表雄酮、睾酮和胰岛素样生长因子 1 水平)则下降。许多研究表明,这种分解代谢环境是老年人虚弱和死亡的重要预测因素。虚弱和认知障碍之间存在密切关系,有研究表明,虚弱的发展是认知障碍的结果,而另一些研究则指出,身体虚弱是认知能力下降的决定因素。认知功能下降,通常是记忆力下降,是痴呆的主要症状。认知障碍的“临床前期”发生在痴呆症发病前多年。确定相关的可改变因素,包括激素失调,可能会导致预防认知功能障碍的治疗策略。合成代谢激素在神经保护和神经调节中发挥作用的机制有几种。这些激素促进脑损伤后的恢复,并减轻神经元的丢失。相比之下,甲状腺激素水平升高可能会增加氧化应激和细胞凋亡,导致神经元损伤或死亡。在这篇迷你综述中,我们将讨论老年男性中合成代谢激素水平低、甲状腺激素变化与认知功能之间的关系。然后,鉴于文献中的矛盾数据和痴呆症的多因素起源,我们将引入多种激素失调假说,作为老年男性认知能力下降的更好决定因素。