Departamento de Ciencias Médicas, División de Ciencias de la Salud, Campus León, Universidad de Guanajuato, León 37320, Guanajuato, México.
Behav Brain Funct. 2010 Oct 29;6:67. doi: 10.1186/1744-9081-6-67.
Cognitive deficits such as poor memory, the inability to concentrate, deficits in abstract reasoning, attention and set-shifting flexibility have been reported in middle-aged women. It has been suggested that cognitive decline may be due to several factors which include hormonal changes, individual differences, normal processes of aging and age-related changes in dopaminergic neurotransmission. Catechol-O-methyltransferase (COMT), a common functional polymorphism, has been related to executive performance in young healthy volunteers, old subjects and schizophrenia patients. The effect of this polymorphism on cognitive function in middle-aged healthy women is not well known. The aim of the current study was to investigate whether measures of executive function, sustained attention, selective attention and verbal fluency would be different depending on the COMT genotype and task demand.
We genotyped 74 middle-aged healthy women (48 to 65 years old) for the COMT Val158Met polymorphism. We analyzed the effects of this polymorphism on executive functions (Wisconsin Card Sorting Test), selective attention (Stroop test), sustained attention (Continuous Performance Test) and word generation (Verbal Fluency test), which are cognitive functions that involve the frontal lobe.
There were 27 women with the Val/Val COMT genotype, 15 with the Met/Met genotype, and 32 with the Val/Met genotype. Women carriers of the Val/Val genotype performed better in executive functions, as indicated by a lower number of errors committed in comparison with the Met/Met or Val/Met groups. The correct responses on selective attention were higher in the Val/Val group, and the number of errors committed was higher in the Met/Met group during the incongruence trial in comparison with the Val/Val group. Performance on sustained attention and the number of words generated did not show significant differences between the three genotypes.
These findings indicate that middle-aged women carriers of the Val158 allele, associated with high-activity COMT, showed significant advantage over Met allele in executive processes and cognitive flexibility. These results may help to explain, at least in part, individual differences in cognitive decline in middle-aged women with dopamine-related genes.
中年女性表现出认知缺陷，如记忆力差、注意力不集中、抽象推理能力下降、注意力和定势转移灵活性下降。有人认为，认知能力下降可能是由于多种因素造成的，包括激素变化、个体差异、正常衰老过程以及与年龄相关的多巴胺能神经传递变化。儿茶酚-O-甲基转移酶（COMT）是一种常见的功能性多态性，与年轻健康志愿者、老年受试者和精神分裂症患者的执行表现有关。这种多态性对中年健康女性认知功能的影响尚不清楚。本研究旨在探讨 COMT 基因型和任务需求是否会影响执行功能、持续注意力、选择性注意力和言语流畅性等认知功能的测量结果。
我们对 74 名中年健康女性（48 至 65 岁）进行 COMT Val158Met 多态性基因分型。我们分析了这种多态性对执行功能（威斯康星卡片分类测试）、选择性注意（斯特鲁普测试）、持续注意力（连续作业测试）和单词生成（言语流畅性测试）的影响，这些认知功能都涉及额叶。
27 名女性携带 Val/Val COMT 基因型，15 名女性携带 Met/Met 基因型，32 名女性携带 Val/Met 基因型。与 Met/Met 或 Val/Met 组相比，携带 Val/Val 基因型的女性在执行功能方面表现更好，错误数量更少。在不一致试验中，Val/Val 组的选择性注意正确反应更高，而 Met/Met 组的错误数量更高。在持续注意力和生成的单词数量方面，三种基因型之间没有显著差异。
这些发现表明，携带 Val158 等位基因的中年女性，与高活性 COMT 相关，在执行过程和认知灵活性方面表现出明显优势。这些结果至少部分可以解释与多巴胺相关基因的中年女性认知能力下降的个体差异。
