Letters to the Editor

We read with interest the article by Natunen et al. [1] on the role of the BACE regulating factor, GGA3, in Alzheimer’s disease (AD). In this study, as has been the case with a number of other studies [2-4], the authors utilized human postmortem brain samples to show that the temporal cortex of AD patients had decreased levels of GGA3 compared to that of age-matched controls, although the decrease was not statistically significant [1]. In a separate study, Santosa et al.

We read with great interest the article by Moreno and colleagues [1]. The authors should be congratulated on enlarging our knowledge on retinal nerve fiber layer (RNFL) thickness measurements in Alzheimer’s disease (AD) and other types of dementia. The results of this study show that optical coherence tomography (OCT) seems to be a useful tool for diagnosing dementia syndromes but does not seem to contribute to the differential diagnosis of different types of dementia. Nevertheless, we believe that some supplementary discussion of the problem is needed.

Recently, numerous lifestyle factors have been described that influence the risk of dementia such as smoking, obesity, and physical exercise, or certain nutrients like selenium [1]. Another factor that has received little attention to so far, although it might be of crucial importance in the modern human environment with its increasing complexity and speed-up of daily events, is stress. Psychological stress occurs when individuals face situational demands that exceed their adaptive capacity.

Testosterone and DHEA are Directly Involved in Alzheimer’s Disease. This explanation is relevant within an evolutionary context. I think mammals evolved because of natural selection for dehydroepiandrosterone (DHEA) [1]. This is based on my principal hypothesis that DHEA increases replication and transcription of DNA, that is, DHEA increases gene activation.