Serum Homocysteine and Folate Levels are Associated With Late-life Dementia in a Korean Population.

Objectives: We aimed to determine whether serum levels of homocysteine (Hcy) and its biological determinants, folate and vitamin B12, are related to cognitive decline in elderly people.

Methods: The concentrations of total Hcy, folate, and vitamin B12 were measured in serum samples from 424 cognitively normal controls, 382 mild cognitive impairment patients, and 56 dementia patients from Ansan Geriatric cohort. The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological battery was used to evaluate cognitive functions.

An aminopeptidase from Streptomyces sp. KK565 degrades beta amyloid monomers, oligomers and fibrils.

The accumulation of beta amyloid (Aβ) has been a primary target for Alzheimer disease therapeutic strategies. Previously, we discovered an activity from Streptomyces sp. KK565 growth media that inhibits Aβ aggregation.

Plasma carbonic anhydrase II protein is elevated in Alzheimer's disease.

Carbonic anhydrase (CA) plays a critical role in pH regulation, long-term synaptic transformation, and is associated with mental retardation, Alzheimer's disease (AD), and Down syndrome. There is accumulating evidence that CAII is increased in AD brain. The present study focused on the determination of CAII protein level in blood plasma samples using immunoblot and ELISA methods.

Obesity and depressive symptoms in elderly Koreans: evidence for the "Jolly Fat" hypothesis from the Ansan Geriatric (AGE) Study.

The current study is to examine the association between obesity and depressive symptoms and to test the validity of "Jolly Fat" hypothesis in elderly Koreans. A total of 1229 elderly (60-85 years old) Koreans selected from the Ansan Geriatric Study participated in this study. Body mass index (BMI) was calculated from the measured weights and heights of subjects.

Ubc9 gene polymorphisms and late-onset Alzheimer's disease in the Korean population: a genetic association study.

Ubiquitin-conjugating enzyme E2I (Ubc9) ligates small ubiquitin-related modifier (SUMO) to target proteins, resulting in changes of their localization, activity, or stability. Sumoylation of amyloid precursor protein (APP) was reported to be associated with decreased levels of beta amyloid (Abeta) aggregates, suggesting that sumoylation may play a role in the pathogenesis of Alzheimer's disease (AD). We investigated the association between genetic variations of Ubc9 gene (UBE2I) and late-onset Alzheimer's disease (AD).

Nicotinamide reduces dopamine in postnatal hypothalamus and causes dopamine-deficient phenotype.

Dopamine is an important neurotransmitter in the human central nervous system and also plays a key role in the development of postnatal brains. We previously reported that nicotinamide, a SIRT1 inhibitor, regulates tyrosine hydroxylase (TH) expression in vitro. To investigate the effect of nicotinamide-mediated TH regulation in vivo, nicotinamide was chronically injected into neonatal mice.

SIRT1 regulates tyrosine hydroxylase expression and differentiation of neuroblastoma cells via FOXO3a.

To examine the function of SIRT1 in neuronal differentiation, we employed all-trans retinoic acid (ATRA)-induced differentiation of neuroblastoma cells. Nicotinamide inhibited neurite outgrowth and tyrosine hydroxylase (TH) expression. Inhibition of PARP or histone deacetylase did not inhibit TH expression, showing the effect to be SIRT1 specific.

Association of BACE1 gene polymorphism with Alzheimer's disease in Asian populations: meta-analysis including Korean samples.

Background: Beta-site amyloid precursor protein cleaving enzyme (BACE) is a candidate risk factor for Alzheimer's disease (AD) from its key role in beta-amyloid generation. Previous genetic association studies of BACE1 gene have yielded conflicting results. This study is an attempt to clarify whether the common SNP in exon 5 of BACE1 (rs638405, Val262) is associated with a risk for late-onset AD.

No association of prion protein gene polymorphisms with Alzheimer's disease in Korean population.

The polymorphism at codon 129 (M129V) of the human prion protein gene (PRNP) is a known risk factor for Creutzfeldt-Jakob disease (CJD) in Caucasians. There are few reports of this polymorphism's effect on memory and on the risk of Alzheimer's disease (AD). The M129V genotype distributions among Asians are very different from Caucasians.

ApoE-epsilon 4-dependent association of the choline acetyltransferase gene polymorphisms (2384G>A and 1882G>A) with Alzheimer's disease.

Background: One of the characteristic features of Alzheimer's disease (AD) is the degeneration of the cholinergic system. The gene encoding choline acetyltransferase (ChAT), a key enzyme in cholinergic function, is a candidate gene conferring risk for AD. But the genetic association of the enzyme with AD has been controversial.