Angiotensin-converting enzyme gene polymorphisms and risk for sporadic Alzheimer’s disease: a meta-analysis

Very important pharmacogenetic variants landscape and potential clinical relevance in the Zhuang population from Yunnan province

The gradual evolution of pharmacogenomics has shed light on the genetic basis for inter-individual drug response variations across diverse populations. This study aimed to identify pharmacogenomic variants that differ in Zhuang population compared with other populations and investigate their potential clinical relevance in gene-drug and genotypic-phenotypic associations. A total of 48 variants from 24 genes were genotyped in 200 Zhuang subjects using the Agena MassARRAY platform. The allele frequencies and genotype distribution data of 26 populations were obtained from the 1000 Genomes Project, followed by a comparison and statistical analysis. After Bonferroni correction, significant differences in genotype frequencies were observed of CYP3A5 (rs776746), ACE (rs4291), KCNH2 (rs1805123), and CYP2D6 (rs1065852) between the Zhuang population and the other 26 populations. It was also found that the Chinese Dai in Xishuangbanna, China, Han Chinese in Beijing, China, and Southern Han Chinese, China showed least deviation from the Zhuang population. The Esan in Nigeria, Gambian in Western Division, The Gambia, and Yoruba in Ibadan, Nigeria exhibited the largest differences. This was also proved by structural analysis, Fst analysis and phylogenetic tree. Furthermore, these differential variants may be associated with the pharmacological efficacy and toxicity of Captopril, Amlodipine, Lisinopril, metoclopramide, and alpha-hydroxymetoprolol in the Zhuang population. Our study has filled the gap of pharmacogenomic information in the Zhuang population and has provided a theoretical framework for the secure administration of drugs in the Zhuang population.

Utilizing Proteomic Approaches to Uncover the Neuroprotective Effects of ACE Inhibitors: Implications for Alzheimer's Disease Treatment

Two types of angiotensin-converting enzyme (ACE) inhibitors, lisinopril and benazepril HCl, were tested in neuroblastoma cells and found to upregulate low-density lipoprotein-receptor-related protein 1B (LRP1B) and 14-3-3 protein zeta/delta. Additionally, benazepril HCl was found to increase the expression of calreticulin. The upregulation of these proteins by ACE inhibitors may contribute to the amelioration of cognitive deficits in Alzheimer's disease/dementia, as well as the clinically observed deceleration of functional decline in Alzheimer's patients. This discovery suggests that the supplementation of ACE inhibitors may promote neuronal cell survival independently of their antihypertensive effect. Overall, these findings indicate that ACE inhibitors may be a promising avenue for developing effective treatments for Alzheimer's disease.

Association between an angiotensin-converting enzyme gene polymorphism and Alzheimer's disease in a Tunisian population

BACKGROUND

The angiotensin-converting enzyme gene (ACE) insertion/deletion (I/D or indel) polymorphism has long been linked to Alzheimer's disease (AD), but the interpretation of established data remains controversial. The aim of this study was to determine whether the angiotensin-converting enzyme is associated with the risk of Alzheimer's disease in Tunisian patients.

METHODS

We analyzed the genotype and allele frequency distribution of the ACE I/D gene polymorphism in 60 Tunisian AD patients and 120 healthy controls.

RESULTS

There is a significantly increased risk of AD in carriers of the D/D genotype (51.67% in patients vs. 31.67% in controls; p = .008, OR = 2.32). The D allele was also more frequently found in patients compared with controls (71.67% vs. 56.25%; p = .003, OR = 2.0). Moreover, as assessed by the Mini-Mental State Examination, patient D/D carriers were more frequently found to score in the severe category of dementia (65%) as compared to the moderate category (32%) or mild category (3%).

CONCLUSIONS

The D/D genotype and D allele of the ACE I/D polymorphism were associated with an increased risk in the development of AD in a Tunisian population. Furthermore, at the time of patient evaluation (average age 75 years), patients suffering with severe dementia were found predominantly in D/D carriers and, conversely, the D/D genotype and D allele were more frequently found in AD patients with severe dementia. These preliminary exploratory results should be confirmed in larger studies and further work is required to explore and interpret possible alternative findings in diverse populations.

Renin-angiotensin system gene expression and neurodegenerative diseases

Hypothesis:

Single nucleotide polymorphisms and altered gene expression of components of the renin–angiotensin system (RAS) are associated with neurodegenerative diseases.

Introduction:

Drugs that interact with the RAS have been shown to affect the course of neurodegenerative disease, suggesting that abnormalities in the RAS may contribute to neurodegenerative disease.

Materials and methods:

A meta-analysis of genome-wide association studies and gene expression data for 14 RAS-related proteins was carried out for five neurodegenerative diseases: Alzheimer’s disease, Parkinson’s disease, narcolepsy, amyotrophic lateral sclerosis and multiple sclerosis.

Results:

No single nucleotide polymorphisms in any of the 14 RAS-related protein genes were significantly associated with the five neurodegenerative diseases investigated. There was an inverse association between expression of ATP6AP2, which encodes the (pro)renin receptor, and multiple sclerosis, Alzheimer’s disease and Parkinson’s disease. An association of AGTR, which encodes the AT₁ angiotensin II receptor, and Parkinson’s disease and Alzheimer’s disease was also observed.

Conclusions:

To date, no single nucleotide polymorphisms in components of the RAS can be definitively linked to the neurodegenerative diseases evaluated in this study. However, altered gene expression of several components of the RAS is associated with several neurodegenerative diseases, which may indicate that the RAS contributes to the pathology of these diseases.