Cherrier M M, Plymate S, Mohan S, Asthana S, Matsumoto A M, Bremner W, Peskind E, Raskind M, Latendresse S, Haley A P, Craft S
Department of Psychiatry and Behavioral Sciences, University of Washington Medical School, 1959 NE Pacific, Box 356560, Seattle, WA 98195, USA.
Psychoneuroendocrinology. 2004 Jan;29(1):65-82. doi: 10.1016/s0306-4530(02)00136-1.
Our laboratory has previously reported that testosterone (T) administration to older men significantly improves cognitive function. This study examined potential changes in insulin-like growth factor (IGF) IGF-I, IGF-II and IGF-related binding proteins in response to T administration in older men and their relationship to cognitive functioning.
Twenty-five healthy community dwelling volunteers, ranging in age from 50-80 years were randomized to receive weekly intra-muscular (i.m.) injections of either 100 mg T enanthate or placebo (saline) for 6 weeks. Serum hormone levels and cognitive functioning was assessed at baseline and twice during treatment.
Significant positive associations between IGF-I and IGF-II and spatial memory, spatial reasoning, and verbal fluency were observed after 6 weeks of T administration. Increased serum T levels from treatment were positively associated with improvement in spatial reasoning performance, whereas estradiol was associated with a decline in divided attention performance. Serum IGF-I, IGF-II and IGFBPs did not change in response to T treatment.
Our results suggest that T, estradiol and IGF-I may have independent and selective effects on cognitive functioning. Positive associations between T levels and cognition are consistent with an effect of androgen treatment, whereas positive associations between IGF-I levels and cognition are reflective of a relationship between endogenous IGF-I levels and cognition.
我们实验室之前报道过，对老年男性给予睾酮（T）可显著改善认知功能。本研究检测了老年男性在接受T治疗后胰岛素样生长因子（IGF）IGF-I、IGF-II及IGF相关结合蛋白的潜在变化，以及它们与认知功能的关系。
25名年龄在50至80岁之间的健康社区志愿者被随机分为两组，一组每周接受100mg庚酸睾酮的肌肉注射，另一组接受安慰剂（生理盐水）注射，为期6周。在基线期及治疗期间评估两次血清激素水平和认知功能。
给予T治疗6周后，观察到IGF-I和IGF-II与空间记忆、空间推理及语言流畅性之间存在显著正相关。治疗后血清T水平升高与空间推理能力的改善呈正相关，而雌二醇与注意力分散能力的下降有关。血清IGF-I、IGF-II和IGF结合蛋白对T治疗无反应。
我们的结果表明，T、雌二醇和IGF-I可能对认知功能有独立且选择性的影响。T水平与认知之间的正相关与雄激素治疗的效果一致，而IGF-I水平与认知之间的正相关反映了内源性IGF-I水平与认知之间的关系。
