[The plasma level of amyloid-ß is associated with cognitive decline: a two years follow-up study in Xi'an rural areas].

Objective: To explore the relationship between plasma amyloid-ß (Aß) and cognitive decline during 2 year follow-up in a population-based cohort in Xi'an rural areas. Methods: The study was conducted in Qubao village in Xi'an suburbs cognitively normal residents over 40 years old were recruited from October 2014 to March 2015 and given a face-to-face standardized interview. Mini-mental state examination (MMSE) was employed to evaluate the global cognitive function, and quantification of plasma Aß was measured by sandwich enzyme-linked immunosorbent assay (ELISA) at baseline. Two years later, MMSE was tested at the end of study. Then logistic regression was performed to analyze the relationship between baseline Aß and cognitive change during 2 year follow-up. Results: A total of 1 020 participants completed the study, among whom 223 subjects (21.9%) presented MMSE scores decline (defined as MMSE scores decreased ≥2 points). Compared with those without decline, participants in the MMSE decline group were older (P<0.001) and had lower education level (P<0.001), while gender, hypertension, hyperlipemia, diabetes mellitus and APOE genotype were not significantly different between two groups. One-way analysis of variance (ANOVA) showed that the MMSE score decline was slighter in the lower tertile of baseline Aß(1)-40 compared with middle tertile (P=0.012), while MMSE decline were similar between different Aß(1)-42 level groups and Aß(1-42)/Aß(1-40) ratio groups (P=0.758, P=0.671, respectively). Multivariable logistic regression analysis showed that MMSE scores in the lower baseline plasma Aß(1-40) level declined more slowly (OR=0.565, 95%CI 0.379-0.845, P=0.005). However, the MMSE decline were also similar among different baseline plasma Aß(1-42) levels groups and Aß(1-42)/Aß(1-40) ratio groups. Conclusion: Population with lower level of baseline plasma Aß(1-40) manifests lower cognitive decline during 2 years, however further investigation on dynamics of plasma Aß and long term follow up are needed.

Hypermethylation of ERа-A gene and high serum homocysteine level are correlated with cognitive impairment in white matter hyperintensity patients.

OBJECTIVE: To investigate the methylation status in promoter region of estrogen receptor alpha (ERа)-A gene and its relation with plasma homocysteine (Hcy) level and cognitive impairment in white matter hyperintensity (WMH) patients. PATIENTS AND METHODS: 210 patients aged 65 and older were selected. The methylation status of CpG islands in ERа-A gene promoter was analyzed by nested methylation-specific PCR. Serum Hcy and estradiol levels were measured by enzyme-linked immunosorbent assay. Cognitive function were evaluated using minimum mental state examination, the montreal cognitive assessment, Stroop color-word test, symbol digit modalities, trail making test B and instrumental activities of daily living (IADL). The severity of WMH was evaluated with the Fazekas scale by brain magnetic resonance imaging. RESULTS: We found a significant association between the severity of WMH and CpG island methylation of ERа-A gene (P < 0.05). Multiple regression analysis showed that serum Hcy level, methylation of ERа-A gene and WMH severity were significant determining factors for cognitive impairment (P < 0.05). The spearman rank correlation analysis showed a significant correlation of methylation of ERа-A gene with serum Hcy level, WMH severity, cognitive function and IADL status (P < 0.05). CONCLUSION: Methylation of ERа-A gene promoter has a high frequency in WMH patients with cognitive impairment and is correlated with high plasma Hcy level.

Interleukin-1 gene cluster polymorphisms and risk of Alzheimer's disease in Chinese Han population.

Interleukin-1 (IL-1) has been implicated as a key cytokine in Alzheimer's disease (AD) pathogenesis. IL-1 gene polymorphisms, especially IL-1A C((-)889)T polymorphism, have been suggested to be associated with AD risk and onset age. To determine if IL-1 polymorphisms are genetic risk factors for developing AD in Chinese Mainland population, we analyzed IL-1A ((-)889), IL-1B ((-)511) and IL-1RN variable number of tandem repeat (VNTR) polymorphisms in a sample of 145 sporadic AD patients and 181 healthy controls. Our data revealed that the three polymorphisms in IL-1 gene cluster might not play a key role in AD pathogenesis in Chinese Mainland Han population.

[An association analysis of apolipoprotein E genotypes with Alzheimer's disease in Chinese population].

OBJECTIVE: To analyse the association of apolipoprotein E genotypes with Alzheimer's disease in Chinese population. METHODS: Using PCR and restriction enzyme digestion, we have analyzed ApoE allele frequency of Alzheimer's disease (AD) patients and healthy controls. RESULTS: Among the 56 cases of AD, the frequency of ApoE epsilon 2, ApoE epsilon 3, ApoE epsilon 4 are 3 (2.7%), 84 (75.0%), 25 (22.3%) respectively, while in the 67 controls they are 9 (6.7%), 115 (85.8%), 10 (7.5%) respectively. The frequencies of the two groups have significant difference (P < 0.01) and the frequency of ApoE epsilon 4 allele is higher in AD than that in the health controls and the statistical treatment suggest that there is significant difference (chi 2 = 10.99, P < 0.01, OR = 3.59, 95% CI = 1.54-8.41). The frequency of the ApoE epsilon 3 is lower in AD than that in the health controls and the difference is also statistically significant(P < 0.05). CONCLUSIONS: Our results are consistent with previous work in that proving the ApoE epsilon 4 allele is one of the risk factors of AD. The results also provide a support for the protection effect of ApoE epsilon 3 allele in developing AD.