Effects of APOE rs429358, rs7412 and GSTM1/GSTT1 Polymorphism on Plasma and Erythrocyte Antioxidant Parameters and Cognition in Old Chinese Adults

Effect of apolipoprotein E ε4 and its modification by sociodemographic characteristics on cognitive measures in South Asians from LASI-DAD

BACKGROUND

We investigated the effects of apolipoprotein E (APOE) ε4 and its interactions with sociodemographic characteristics on cognitive measures in South Asians from the Diagnostic Assessment of Dementia for the Longitudinal Aging Study of India (LASI-DAD).

METHODS

Linear regression was used to assess the association between APOE ε4 and global- and domain-specific cognitive function in 2563 participants (mean age 69.6 ± 7.3 years; 53% female). Effect modification by age, sex, and education were explored using interaction terms and subgroup analyses.

RESULTS

APOE ε4 was inversely associated with most cognitive measures (p < 0.05). This association was stronger with advancing age for the Hindi Mental State Examination (HMSE) score (βε4×age = -0.44, p = 0.03), orientation (βε4×age = -0.07, p = 0.01), and language/fluency (βε4×age = -0.07, p = 0.01), as well as in females for memory (βε4×male = 0.17, p = 0.02) and language/fluency (βε4×male = 0.12, p = 0.03).

DISCUSSION

APOE ε4 is associated with lower cognitive function in South Asians from India, with a more pronounced impact observed in females and older individuals.

HIGHLIGHTS

APOE ε4 carriers had lower global and domain-specific cognitive performance. Females and older individuals may be more susceptible to ε4 effects. For most cognitive measures, there was no interaction between ε4 and education.

An optimized method for PCR-based genotyping to detect human APOE polymorphisms

Background

Apolipoprotein E (APOE) is one of the most polymorphic genes at two single nucleotides (rs429358 and rs7412). The various isoforms of APOE have been associated with a variety of diseases, including neurodegenerative, type 2 diabetes, etc. Hence, predicting the APOE genotyping is critical for disease risk evaluation. The purpose of this study was to optimize the tetra amplification refractory mutation system (Tetra-ARMS) PCR method for the detection of APOE mutations.

Material and methods

Here, in our optimized Tetra-ARMS PCR method, different factors like cycle conditions, using HiFidelity enzyme instead of Taq polymerase and setting its best concentration, and the lack of using dimethylsulfoxide (DMSO) for amplifying the GC-regions were set up for all primer pairs. The sensitivity and accuracy were tested. For validation of the assay, the results were compared with known genotypes for the APOE gene that were previously obtained by two independent methods, RFLP and Chip-typing.

Results

Successful Tetra-ARMS PCR and genotyping are influenced by multiple factors. Our developed method enabled us to amplify the DNA fragment by 25 cycles without adding any hazardous reagent, like DMSO. Our findings showed 100 % accuracy and sensitivity of the optimized Tetra-ARMS PCR while both criteria were 95 % for RFLP and 100 % for the chip-typing method. In addition, our results showed 91 % and 100 % consistency with RFLP and chip typing methods, respectively.

Conclusions

Our current method is a simple and accurate approach for detecting APOE polymorphisms within a large sample size in a short time and can be performed even in low-tech laboratories.

Correlation among sleep quality, physical frailty and cognitive function of the older adults in China: the mediating role

Objective

To explore the correlation among sleep quality, physical frailty, and cognitive function in the older adults in community, and to explore the mediating role of sleep quality.

Methods

A total of 1,182 community-based older adults were investigated with frailty phenotype (FP), Pittsburgh sleep quality index (PISQI), Montreal cognitive assessment (MoCA) and self-made general information questionnaire.

Results

The incidence of physical frailty among the older adults in the community was 25.8% and the incidence of cognitive decline was 19.5%. Cognitive function was negatively correlated with physical frailty (r = -0.236, p < 0.01) and sleep quality (r = -0.558, p < 0.01). Sleep quality was positively correlated with physical frailty (r = 0.337, p < 0.01).

Conclusion

The physical frailty of the older adults has a direct prediction effect on cognitive function, and is regulated by the mediating role of sleep quality. Sleep quality partially mediates the relationship between cognitive dysfunction and physical frailty, which is a new insight into the study of cognition and physical frailty in the older adults. In the future, we can take measures to improve the sleep quality of the older adults, so as to reduce the occurrence of cognitive dysfunction and physical frailty of the older adults.

Combined homocysteine and apoE rs429358 and rs7412 polymorphism in association with serum lipid levels and cognition in Chinese community-dwelling older adults

BACKGROUND

ApoE gene polymorphism and serum total homocysteine (tHcy) has been reportedly associated with cognition. In this study, we assessed the association of combined ApoE gene polymorphism and tHcy with cognition in Chinese elder adults.

METHODS

A cross- sectional study was carried out by recruiting 1458 community-dwelling people aged 55+ and above in Beijing in 2009. All participants were interviewed using a standard questionnaire and underwent a physical examination. The mini-mental scale examination (MMSE) score was used in assessing cognitive function. Fasting venous blood samples were taken for ApoE rs429358, rs7412 genotyping, tHcy and other serum lipid measurements.

RESULTS

Participants with high serum tHcy level showed a relatively lower orientation, attention abilities as well as the total MMSE score than the group with normal tHcy after adjusting confounding factors. ApoE rs429358 and rs7412 variants were observed to have the highest serum TC and TG level in the subjects with high serum tHcy level (p <  0.05). Cognition of the subjects was found to be significantly associated with high serum tHcy level and ApoE genetic polymorphism (p <  0.05). Independent of age, BMI, education levels, smoking and alcohol drinking, the worst cognitive ability were detected in the high serum tHcy level subjects with ApoE rs429358C/T and rs7412 C/T as compare with other groups, especially orientation function, memory and delayed recall ability and attention ability.

CONCLUSION

High serum tHcy level in combination with ApoE rs429358 and rs7412 variants might be linked with serum lipid levels and cognition, particularly for orientation function and memory and delayed recall ability in old Chinese adults.

MassARRAY multigene screening combined with LDL-C and sdLDL-C detection for more favorable outcomes in type 2 diabetes mellitus therapy

BACKGROUND

To determine the clinical value of multigene polymorphisms, LDL-C and sdLDL-C on T2DM therapy.

METHODS

In total, 352 T2DM patients before and after treatment and 48 healthy individuals were enrolled in this study. LDL-C and sdLDL-C were detected in 352 T2DM patients and 48 healthy individuals by Quantimetrix Lipoprint System. The 11 gene polymorphisms-HTR3B (rs2276307, A > G), APOE (rs7412, c.526C > T), APOE (rs429358, c.388 T > C), CYP2C9*3 (rs1057910, c.1075A > C), KIF6 (rs20455, c.2155 T > C), HMGCR (rs17238540, T > G), HMGCR (rs17244841, A > T), ABCB1 (rs2032582, A > C/T), HTR7 (rs1935349, C > T), SLCO1B1 (rs4149056, c.521 T > C), and CETP (rs708272, G > A)-were screened in these 352 T2DM patients by the Agena Bioscience MassARRAY system before therapy.

RESULTS

Genetic polymorphisms associated with T2DM and statin effects in pretreatment patients were detected, then results showed that all 11 genes had heterozygous mutation, and 7 genes had homozygous mutation in 352 T2DM patients, more specifically reflected that these gene polymorphisms were common in Chinese T2DM patients. LDL-C and sdLDL-C were detected before and after treatment, sdLDL mainly existed in T2DM patients, and T2DM patients had higher mean levels of sdLDL-C than healthy people. After pharmacotherapy, the coincidence rates of decreases in LDL-C and sdLDL-C levels were 88.35% (311/352) and 84.09% (296/352), consistent with patients in remission.

CONCLUSIONS

Gene polymorphisms related to pharmacotherapy were common in Chinese T2DM patients. And the expression of LDL-C and sdLDL-C was consistent with the T2DM disease course. Combined multigene screening before therapy and LDL-C and sdLDL-C detection before and after therapy could better assist T2DM treatment.

Cardiovascular and Metabolic Protection by Vitamin E: A Matter of Treatment Strategy?

Cardiovascular diseases (CVD) cause about 1/3 of global deaths. Therefore, new strategies for the prevention and treatment of cardiovascular events are highly sought-after. Vitamin E is known for significant antioxidative and anti-inflammatory properties, and has been studied in the prevention of CVD, supported by findings that vitamin E deficiency is associated with increased risk of cardiovascular events. However, randomized controlled trials in humans reveal conflicting and ultimately disappointing results regarding the reduction of cardiovascular events with vitamin E supplementation. As we discuss in detail, this outcome is strongly affected by study design, cohort selection, co-morbidities, genetic variations, age, and gender. For effective chronic primary and secondary prevention by vitamin E, oxidative and inflammatory status might not have been sufficiently antagonized. In contrast, acute administration of vitamin E may be more translatable into positive clinical outcomes. In patients with myocardial infarction (MI), which is associated with severe oxidative and inflammatory reactions, decreased plasma levels of vitamin E have been found. The offsetting of this acute vitamin E deficiency via short-term treatment in MI has shown promising results, and, thus, acute medication, rather than chronic supplementation, with vitamin E might revitalize vitamin E therapy and even provide positive clinical outcomes.

Association Between Episodic Memory and Genetic Risk Factors for Alzheimer's Disease in South Asians from the Longitudinal Aging Study in India-Diagnostic Assessment of Dementia (LASI-DAD)

BACKGROUND/OBJECTIVES

Genetic factors play an important role in Alzheimer's disease (AD) and cognitive aging. However, it is unclear whether risk loci identified in European ancestry (EA) populations have similar effects in other groups, such as South Asians.

DESIGN

We investigated the allelic distribution and cognitive associations of 56 known AD risk single-nucleotide polymorphisms (SNPs) identified from three EA genome-wide association studies (EA-GWASs) in a South Asian population. Single SNP and genetic risk score (GRS) associations with measures of episodic memory were assessed.

SETTING

The Diagnostic Assessment of Dementia for the Longitudinal Aging Study in India (LASI-DAD).

PARTICIPANTS

A total of 906 LASI-DAD participants from diverse states in India.

MEASUREMENTS

Participants were genotyped using the Illumina Global Screening Array and imputed with 1000G Phase 3v5. Cognitive measures included total learning and delayed word recall.

RESULTS

Although only a few SNPs were significantly associated with memory scores (P < .05), effect estimates from the EA-GWAS and the LASI-DAD showed moderate correlation (0.35-0.88) in the expected direction. GRSs were also associated with memory scores, although percentage variation explained was small (0.1%-0.6%).

CONCLUSIONS

Discrepancies in allele frequencies and cognitive association results suggest that genetic factors found predominantly through EA-GWASs may play a limited role in South Asians. However, the extent of differences in the genetic architecture of AD and cognition in EA and South Asians remains uncertain. There is also a critical need to perform a more comprehensive assessment of the mutational spectrum of South Asia to identify novel genetic variants associated with AD and cognition in this population. J Am Geriatr Soc 68:S45-S53, 2020.

Genes and Eating Preferences, Their Roles in Personalized Nutrition

At present, personalized diets, which take into account consumer genetic characteristics, are growing popular. Nutrigenetics studies the effect of gene variations on metabolism and nutrigenomics, which branches off further and investigates how nutrients and food compounds affect genes. This work deals with the mutations affecting the assimilation of metabolites, contributing to nutrigenetic studies. We searched for the genes responsible for eating preferences which allow for the tailoring of personalized diets. Presently, genetic nutrition is growing in demand, as it contributes to the prevention and/or rehabilitation of non-communicable diseases, both monogenic and polygenic. In this work, we showed single-nucleotide polymorphisms in genes-missense mutations that change the functions of coded proteins, resulting in a particular eating preferences or a disease. We studied the genes influencing food preferences-particularly those responsible for fats and carbohydrates absorption, food intolerance, metabolism of vitamins, taste sensations, oxidation of xenobiotics, eating preferences and food addiction. As a result, 34 genes were identified that affect eating preferences. Significant shortcomings were found in the methods/programs for developing personalized diets that are used today, and the weaknesses were revealed in the development of nutrigenetics (inconsistency of data on SNP genes, ignoring population genetics data, difficult information to understand consumer, etc.). Taking into account all the shortcomings, an approximate model was proposed in the review for selecting an appropriate personalized diet. In the future, it is planned to develop the proposed model for the compilation of individual diets.

Association of MTHFR, SLC19A1 Genetic Polymorphism, Serum Folate, Vitamin B12 and Hcy Status with Cognitive Functions in Chinese Adults

Background/Aim: Studies have indicated a relationship between either gene polymorphism or in vivo B vitamins’ nutritional status with cognition in the elderly. However, the combined effects of MTHFR and SLC19A1gene polymorphism with serum folate and vitamin B₁₂ levels on cognition in Chinese adult population remain unclear. Methods: Demographic information of 426 Chinese adults aged from 55 to 90 were collected by a well designed self-administered questionnaire. The Montreal Cognitive Assessment test was utilized to evaluate the cognition status of the participants. MTHFR and SLC19A1 genotyping was analyzed using polymerase chain reaction-ligase detection reaction (PCR- LDR) method. Serum folate, vitamin B₁₂ and homocysteine (Hcy) levels were detected by commercial assay kits. Pearson’s correlation was used for data analyses and statistical significance was set at p < 0.05. Results: Serum Hcylevels demonstrated a negative correlation with serum folate (r = −0.301) and vitamin B₁₂ (r = −0.292) levels. The negative correlation found between serum Hcy levels and attention ability was observed in all 426 studied subjects (r = −0.122). Subjects with MTHFR 677 T/T and 1298 A/A genotypes demonstrated a higher serum Hcy levels (p < 0.05). Carriers of MTHFR (1298 A/C + C/C and 1793 G/A) and SLC19A1 80 G/G genotypes showed lower abstraction and delayed memory ability, respectively (p < 0.05). Subjects with MTHFR 1793 G/A genotype along with low serum folate concentration demonstrated the lowest name and orientation abilities. The effects of MTHFR 1793 G/A genotype on cognitive performance were dependent on the status of serum vitamin B₁₂. Conclusion: Cognition of adults was associated with MTHFR, SLC19A1 gene polymorphism and serum Hcy levels. This study clearly establishes a combined effect of MTHFR gene polymorphism and serum B vitamins levels on cognition in Chinese adults.

Polymorphisms of apolipoprotein E and aneurysmal subarachnoid haemorrhage: A meta-analysis

Subarachnoid haemorrhage (SAH) is characterised by bleeding in the subarachnoid space in the brain. There are various polymorphisms in genes which are associated with this disease. We performed a systematic meta- analysis to investigate the relationship of APOE polymorphism on aSAH. A comprehensive literature search was done in the Pubmed database, Science Direct, Cochrane library and Google Scholar. The OR and 95% CI were evaluated for the gene and aSAH association using fixed and random effect models. Publication bias was assessed using Begg's funnel plot and Egger's regression test. All statistical evaluations were done using the software Review Manager 5.0 and Comprehensive Meta Analysis v2.2.023. A total of 9 studies were assessed on APOE polymorphism (1100 Cases, 2732 Control). Meta analysis results showed significant association in ε2/ ε2 versus ε3/ε3, ε2 versus ε3 genetic models and ε2 allele frequency. In subgroup analysis statistically significant association was observed in Asians in the genetic models ε2/ ε2 versus ε3/ε3, ε2/ε3 versus ε3/ε3, ε2 versus ε3 and also in ε2 allele frequency. However, in Caucasian population only ε2/ε2 versus ε3/ε3 genetic model showed significant association between APOE and risk of aSAH. In this meta-analysis study, the ε2/ε2 genotype is associated with increased risk of aSAH.

Analysis of the Relationship between Estradiol and Follicle-Stimulating Hormone Concentrations and Polymorphisms of Apolipoprotein E and LeptinGenes in Women Post-Menopause

Background: Menopause is the permanent cessation of menstruation due to loss of ovarian follicular activity. A review of the available literature indicates that correlations between the changes that take place in a woman’s body after menopause and different genetic variants are still being sought. Methods: The study was conducted in 252 women who had completed physiological menopause. The women were divided into groups according to the time elapsed since menopause. The total concentrations of estradiol and follicle-stimulating hormone were determined by means of electrochemiluminescence. The apolipoprotein E (APOE) and lepitn (LEP) genotypes were determined by real-time PCR and polymerase chain reaction–restriction fragment length polymorphism, respectively. Results: We observed that people with the APOE3/E3 genotype entered menopause insignificantly later compared to other genotypes. Additionally, in the group of patients with the APOE3/E3 genotypes, differences in the E2 concentration were significantly related to the time since their last menstruation. There is no association found in the literature between these polymorphisms of the LEP gene and hormones. Conclusions: To date, attempts to formulate a model describing the association between E2 and FSH concentration with the polymorphisms of various genes of menopause in women have not been successful. This relationship is difficult to study because of the number of nongenetic factors. Environmental factors can explain variation in postmenopausal changes in hormone levels.

Apolipoprotein E polymorphisms increase the risk of post-stroke depression

Recent reports have shown that apolipoprotein E (APOE) polymorphisms are involved in neurodegenerative disease. However, it is unclear whether APOE affects post-stroke depression. Accordingly, we hypothesized that APOE polymorphisms modify the risk of post-stroke depression. Here, we performed a hospital-based case-control study (including 76 cerebral infarction cases with post-stroke depression, 88 cerebral infarction cases without post-stroke depression, and 109 controls without any evidence of post-stroke depression or cerebral infarction) to determine possible association between APOE rs429358 and rs7412 polymorphisms and risk of post-stroke depression. Our findings show no difference among the groups with regards genotype distribution of the rs7412 polymorphism. In contrast, APOE genotypes with rs429358-C alleles increased the risk of post-stroke depression. Further, the rs429358 polymorphism was associated with significantly decreased regional cerebral blood flow values in the left temporal lobe of post-stroke depression cases. Additionally, the rs429358 polymorphism was not only associated with depression severity, but with increasing serum levels of total cholesterol. These results suggest that the APOE rs429358 polymorphism is associated with increased risk of developing post-stroke depression, and that APOE rs429358-C allele genotypes may be detrimental to recovery of nerve function after stoke. Indeed, these findings provide clinical data for future post-stroke depression gene interventions.