Reduced memory and executive functioning significantly relates to participation in early phase clinical research in Alzheimer's disease

Abstract Objective To investigate the effects of Type 2 Diabetes (T2D) on performance on attention and executive function measures in a sample of MCI patients. Method Individuals with a clinician diagnosis of MCI with T2D and [n = 719,Mage = 75.24,50.3% female] and MCI persons without T2D [n = 719,Mage = 75.21,47.1% female] were selected from the Alzheimer’s Disease Research Centers database by the National Institute on Aging. Those with motor disturbances were excluded from the analysis. Significant differences (p < 0.001) were found for race and education between groups. Results Multiple ANCOVAs controlled for gender, education, age, and race on performance. Significant differences (p < 0.001) were found in performance on the Trail Making Test [A, B], Digit Span forward [longest recall, correct trials], Digit Span backward [longest recall, correct trials], and Verbal Fluency tasks [F word, L words]. No significant differences were found in the animal and vegetable naming fluency tasks. The T2D group showed poorer mean scores on every test analyzed. Conclusion Results indicated modestly lower performance on measures of attention and executive functioning in MCI patients with comorbid T2D. Previous research supports these conclusions, as T2D has been associated with increased risk for dementia, accelerated decline from MCI to dementia, and modestly lower scores on cognitive tests via effects of microvascular function and altered glucose metabolism. Future studies should aim to identify protective factors in T2D cognitive decrements while controlling for exercise, diet, SES, and underlying medical comorbidities. The NACC database is funded by NIA/NIH Grant U01 AG016976. NACC data are contributed by the NIA-funded Alzheimer’s Disease Research Centers.

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pLG72 levels increase in early phase of Alzheimer’s disease but decrease in late phase

Scientific Reports ◽

10.1038/s41598-019-49522-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 5

Author(s):

Chieh-Hsin Lin ◽

Chih-Chiang Chiu ◽

Chiung-Hsien Huang ◽

Hui-Ting Yang ◽

Hsien-Yuan Lane

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Amino Acid ◽

Early Phase ◽

Late Phase ◽

Acid Oxidase ◽

Matched Cohort ◽

Amino Acid Oxidase ◽

Gender And Age ◽

Neurodegenerative Dementia

Abstract pLG72, named as D-amino acid oxidase activator (although it is not an activator of D-amino acid oxidase demonstrated by later studies), in mitochondria has been regarded as an important modulator of D-amino acid oxidase that can regulate the N-methyl-D-aspartate receptor (NMDAR). Both oxidative stress in mitochondria and NMDAR neurotransmission play essential roles in the process of neurodegenerative dementia. The aim of the study was to investigate whether pLG72 levels changed with the severity of neurodegenerative dementia. We enrolled 376 individuals as the overall cohort, consisting of five groups: healthy elderly, amnestic mild cognitive impairment [MCI], mild Alzheimer’s disease [AD], moderate AD, and severe AD. pLG72 levels in plasma were measured using Western blotting. The severity of cognitive deficit was principally evaluated by Clinical Dementia Rating Scale. A gender- and age- matched cohort was selected to elucidate the effects of gender and age. pLG72 levels increased in the MCI and mild AD groups when compared to the healthy group. However, pLG72 levels in the moderate and severe AD groups were lower than those in the mild AD group. D-serine level and D- to total serine ratio were significantly different among the five groups. L-serine levels were correlated with the pLG72 levels. The results in the gender- and age- matched cohort were similar to those of the overall cohort. The finding supports the hypothesis of NMDAR hypofunction in early-phase dementia and NMDAR hyperfunction in late-phase dementia. Further studies are warranted to test whether pLG72 could reflect the function of NMDAR.

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