ABSTRACT
Objective@#Creatine, energy buffer in high energy demanding systems including muscle and brain, may play a beneficial role against neuroinflammation in Alzheimer’s disease (AD), and thus be a potential biomarker. This study aimed to compare the levels of plasma creatine between persons with and without AD and investigate associations of plasma creatine levels with cognitive function and blood-based inflammatory markers. @*Methods@#We classified elderly participants by cognitive statuses: normal cognition (NC, n=17), mild cognitive impairment (MCI,n=21), and AD (n=21). To assess cognitive function and inflammatory condition, we performed neuropsychological tests and mea-sured plasma C-reactive protein (CRP) levels, respectively. @*Results@#Plasma creatine levels were comparable among participants with AD, MCI, and NC. In overall participants, plasma cre-atine levels were not associated with neuropsychological test scores, but negatively associated with plasma CRP levels. In AD group, plasma creatine levels were negatively associated with neuropsychological test scores and, although not significant, CRP levels (p=0.086). In participants without AD (NC plus MCI), these associations disappeared. @*Conclusion@#Plasma creatine levels may not be useful as a biomarker indicating cognitive statuses. However, our results suggest that, in AD, plasma levels of creatine might reflect the extent of neuroinflammation as well as cognitive deterioration.
ABSTRACT
Objective@#A neuropsychological battery is a gold standard for thorough cognitive evaluation. However, it could not be used as a screening test due to its long inspection time and high cost. This study is conducted to identify specific cognitive subdomains that alter even at the early stage of cognitive decline. @*Methods@#Neuropsychological battery results of 575 persons who visited memory clinic were analysed. We classified stages of cognitive decline according to Clinical Dementia Rating (CDR) and CDR-Sum of boxes (CDR-SB). To explore which subdomains can sensitively distinguish normal cognition from the early cognitive impairment, we used Variable Importance in Projection (VIP) in addition to analysis of covariance. @*Results@#We found that scores in subdomain tests such as Rey Complex Figure Test immediate and delayed recall successfully differentiate persons with CDR 0 from those with CDR 0.5 and also persons with CDR-SB 0 from those with CDR-SB 0.5 as indicated by VIP values greater than 1. @*Conclusion@#These results suggest that alterations in visuospatial memory function might be a sensitive sign reflecting the early cognitive decline. The combination of only a few subtests could be also used as a reliable and sensitive screening tool to detect early cognitive impairment.
ABSTRACT
OBJECTIVE: This study aimed to investigate whether maternal negative affectivity (MNA) moderates the effect of genetic polymorphism of SLC6A4 on behavior problems in children. METHODS: Study participants comprised 143 preschoolers and their mothers from South Korea. The Childhood Behavior Checklist and Emotionality, Activity, and Sociability adult scale were used to measure child behavior and maternal affectivity. DNA from saliva was genotyped to determine serotonin transporter polymorphism. RESULTS: MNA appeared to exert effects in externalizing (b=5.78, p<0.001) and internalizing problems (b=6.09, p< 0.001). Interaction between SLCA4 polymorphism and MNA showed effects on externalizing (b=−7.62, p<0.01) and internalizing problems (b=−9.77, p<0.01). Children with two short alleles showed considerable differences in both externalizing and internalizing problems according to MNA; however, children with one short allele or none showed relatively few differences in behavior problems due to maternal affectivity. CONCLUSION: The effect of SLC6A4 polymorphism on child behavior seemed to be moderated by MNA. In addition, the impact of MNA was found to vary based on a child’s genetic risk. High MNA may trigger the risk allele while low MNA causes the risk allele to illicit less behavior problems. Children with two short variants of the SLC6A4 gene may benefit from intervention that modulates MNA.