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1.
Genet Mol Biol ; 44(4): e20210149, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34807224

RESUMO

Mitochondrial complex I (CI) deficiency is the most common oxidative phosphorylation disorder described. It shows a wide range of phenotypes with poor correlation within genotypes. Herein we expand the clinics and genetics of CI deficiency in the brazilian population by reporting three patients with pathogenic (c.640G>A, c.1268C>T, c.1207dupG) and likely pathogenic (c.766C>T) variants in the NDUFV1 gene. We show the mutation c.766C>T associated with a childhood onset phenotype of hypotonia, muscle weakness, psychomotor regression, lethargy, dysphagia, and strabismus. Additionally, this mutation was found to be associated with headaches and exercise intolerance in adulthood. We also review reported pathogenic variants in NDUFV1 highlighting the wide phenotypic heterogeneity in CI deficiency.

2.
Front Mol Biosci ; 8: 632314, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34291080

RESUMO

Several genome-wide association studies (GWAS) have been carried out with late-onset Alzheimer's disease (LOAD), mainly in European and Asian populations. Different polymorphisms were associated, but several of them without a functional explanation. GWAS are fundamental for identifying loci associated with diseases, although they often do not point to causal polymorphisms. In this sense, functional investigations are a fundamental tool for discovering causality, although the failure of this validation does not necessarily indicate a non-causality. Furthermore, the allele frequency of associated genetic variants may vary widely between populations, requiring replication of these associations in other ethnicities. In this sense, our study sought to replicate in 150 AD patients and 114 elderly controls from the South Brazilian population 18 single-nucleotide polymorphisms (SNPs) associated with AD in European GWAS, with further functional investigation using bioinformatic tools for the associated SNPs. Of the 18 SNPs investigated, only four were associated in our population: rs769449 (APOE), rs10838725 (CELF1), rs6733839, and rs744373 (BIN1-CYP27C1). We identified 54 variants in linkage disequilibrium (LD) with the associated SNPs, most of which act as expression or splicing quantitative trait loci (eQTLs/sQTLs) in genes previously associated with AD or with a possible functional role in the disease, such as CELF1, MADD, MYBPC3, NR1H3, NUP160, SPI1, and TOMM40. Interestingly, eight of these variants are located within long non-coding RNA (lncRNA) genes that have not been previously investigated regarding AD. Some of these polymorphisms can result in changes in these lncRNAs' secondary structures, leading to either loss or gain of microRNA (miRNA)-binding sites, deregulating downstream pathways. Our pioneering work not only replicated LOAD association with polymorphisms not yet associated in the Brazilian population but also identified six possible lncRNAs that may interfere in LOAD development. The results lead us to emphasize the importance of functional exploration of associations found in large-scale association studies in different populations to base personalized and inclusive medicine in the future.

3.
Front Mol Biosci ; 8: 630869, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33898514

RESUMO

Complement system (CS) components are associated with Alzheimer's disease (AD), the commonest cause of dementia in the world. Neutrophils can be attracted to amyloid-ß plaques by several pro-inflammatory factors, including the complement anaphylatoxin C5a. They may release neutrophil extracellular traps (NETs), which are chromatin nets associated with myeloperoxidase, elastase, and other enzymes. Some CS molecules, such as C5a, C1q, and CR1, are associated with increased neutrophil recruitment and NETs release. However, the relationship between CS molecules and NETs in AD is poorly understood. In this work, we detected higher NET concentrations in plasma and serum of Brazilian AD patients, than in elderly controls (medians = 2.78 [2.07-6.19] vs. 2.23 [0.33-4.14] ng/mL, p = 0.0005). We discussed these results within the context of our former findings on complement and AD and the context of the literature on complement and NET release, suggesting both as possible therapeutic targets to prevent the progress of the disease.

4.
J Mol Neurosci ; 70(9): 1338-1344, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388800

RESUMO

The CR1 gene has been widely studied in Alzheimer's disease (AD), since its first association with the disease in 2009. Even after 11 years of this discovery, the role of this gene in AD has not yet been fully elucidated and the association of its variants was not validated in Latin American populations. We genotyped five CR1 single nucleotide polymorphisms (SNPs rs6656401, rs3849266, rs2274567, rs4844610, and rs12034383) in up to 162 AD patients and 137 controls through PCR-SSP and iPLEX MassARRAY Platform (Sequenom), and measured soluble CR1 (sCR1) levels in plasma of 40 AD patients and 39 controls with an enzyme-linked immunosorbent assay (ELISA). Homozygosity for haplotype rs3849266*C_rs2274567*A (CA/CA genotype) was associated with susceptibility to AD (OR = 2.94, p = 0.018). Patients presented higher sCR1 levels in plasma than controls (p = 0.038). Furthermore, patients that carry the rs2274567*G allele (p.1208Arg) presented higher sCR1 levels than A/A (p.1208His/His) homozygotes (p = 0.036). This is the first study to validate the association of CR1 polymorphisms with late-onset Alzheimer's disease, as well as to evaluate sCR1 levels in a Latin American population. SNPs present in the regulatory and coding regions of this gene may be playing a key role in the observed association, probably by interfering in Aß plaques clearance. Inhibition may be due to the increase in local sCR1 levels observed in patients, which may result from polymorphisms leading to larger isoforms of CR1 and/or structural alterations of the protein that makes it less functional, as well as increased vesiculation of the molecules.


Assuntos
Doença de Alzheimer/genética , Polimorfismo de Nucleotídeo Único , Receptores de Complemento 3b/genética , Doença de Alzheimer/sangue , Haplótipos , Homozigoto , Humanos , América Latina , Receptores de Complemento 3b/sangue
5.
Arch. endocrinol. metab. (Online) ; 61(5): 484-489, Sept.-Oct. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-887597

RESUMO

Objective Butyrylcholinesterase (BChE) activity has been associated with obesity, lipid concentrations, and CHE2 locus phenotypes. This, the aim of this study was to evaluate the effects of an energetic restriction diet intervention on anthropometrical and biochemical variables and on absolute and relative BChE activity in CHE2 C5+ and CHE2 C5- individuals. Subjects and methods One hundred eleven premenopausal obese women from Southern Brazil participated in an energetic restriction diet intervention (deficit of 2500 kJ/day) for 8 weeks. Their anthropometric and biochemical parameters were evaluated before and after the intervention. Plasma BChE activity was measured, and BChE bands in plasma and CHE2 locus phenotypes were detected by electrophoresis. Results The dietetic intervention decreased anthropometric and biochemical parameters as well as absolute BChE activity and relative activity of the G4 band. The CHE2 C5+ phenotype presented a different effect when compared with the CHE2 C5- phenotype. The CHE2 C5+ phenotype showed an effect in absolute BChE activity and in the relative activity of the G4 form, maintaining higher BChE activity regardless of the metabolic changes. Conclusion In our study, 8 weeks was not sufficient time to lower the body mass index to normal, but it was enough to significantly reduce the absolute BChE activity, which became similar to the levels in nonobese individuals. CHE2 C5+ individuals were resistant to the decrease in BChE activity compared to CHE2 C5- individuals. This shows that the diet did not affect the CHE2 and G4 fraction complex and that the products of the CHE2 locus in association with BChE have a role in energy metabolism, maintaining high levels of enzymatic activity even after dietary intervention.


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Butirilcolinesterase/metabolismo , Restrição Calórica , Obesidade/dietoterapia , Obesidade/enzimologia , Fenótipo , Brasil , Análise de Regressão , Estudos Longitudinais , Metabolismo Energético
6.
Arch Endocrinol Metab ; 61(5): 484-489, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28658346

RESUMO

OBJECTIVE: Butyrylcholinesterase (BChE) activity has been associated with obesity, lipid concentrations, and CHE2 locus phenotypes. This, the aim of this study was to evaluate the effects of an energetic restriction diet intervention on anthropometrical and biochemical variables and on absolute and relative BChE activity in CHE2 C5+ and CHE2 C5- individuals. SUBJECTS AND METHODS: One hundred eleven premenopausal obese women from Southern Brazil participated in an energetic restriction diet intervention (deficit of 2500 kJ/day) for 8 weeks. Their anthropometric and biochemical parameters were evaluated before and after the intervention. Plasma BChE activity was measured, and BChE bands in plasma and CHE2 locus phenotypes were detected by electrophoresis. RESULTS: The dietetic intervention decreased anthropometric and biochemical parameters as well as absolute BChE activity and relative activity of the G4 band. The CHE2 C5+ phenotype presented a different effect when compared with the CHE2 C5- phenotype. The CHE2 C5+ phenotype showed an effect in absolute BChE activity and in the relative activity of the G4 form, maintaining higher BChE activity regardless of the metabolic changes. CONCLUSION: In our study, 8 weeks was not sufficient time to lower the body mass index to normal, but it was enough to significantly reduce the absolute BChE activity, which became similar to the levels in nonobese individuals. CHE2 C5+ individuals were resistant to the decrease in BChE activity compared to CHE2 C5- individuals. This shows that the diet did not affect the CHE2 and G4 fraction complex and that the products of the CHE2 locus in association with BChE have a role in energy metabolism, maintaining high levels of enzymatic activity even after dietary intervention.


Assuntos
Butirilcolinesterase/metabolismo , Restrição Calórica , Obesidade/dietoterapia , Obesidade/enzimologia , Adulto , Brasil , Metabolismo Energético , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Fenótipo , Análise de Regressão
7.
Genet. mol. biol ; 40(2): 408-414, Apr.-June 2017. tab
Artigo em Inglês | LILACS | ID: biblio-892410

RESUMO

Abstract Butyrylcholinesterase (BChE) activity and polymorphisms in its encoding gene had previously been associated with metabolic traits of obesity. This study investigated the association of three single nucleotide polymorphisms (SNPs) in the BCHE gene: -116G > A (rs1126680), 1615GA (rs1803274), 1914A < G (rs3495), with obesity and lipid metabolism markers, body mass index (BMI), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglyceride (TG) levels, and BChE enzymatic activity in obese (BMI≥30/n = 226) and non-obese women (BMI < 25/n = 81). BCHE SNPs genotyping was obtained by TaqMan allelic discrimination assay and by RFLP-PCR. Plasmatic BChE activity was measured using propionylthiocholine as substrate. Similar allele frequencies were found in obese and non-obese women for the three studied SNPs (p > 0.05). The dominant and recessive models were tested, and different effects were found. The -116A allele showed a dominant effect in BChE activity reduction in both non-obese and obese women (p = 0.045 and p < 0.001, respectively). The 1914A > G and 1615GA SNPs influenced the TG levels only in obese women. The 1914G and the 1615A alleles were associated with decreased plasma levels of TG. Thus, our results suggest that the obesity condition, characterized by loss of energy homeostasis, is modulated by BCHE polymorphisms.

8.
Genet Mol Biol ; 40(2): 408-414, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28497838

RESUMO

Butyrylcholinesterase (BChE) activity and polymorphisms in its encoding gene had previously been associated with metabolic traits of obesity. This study investigated the association of three single nucleotide polymorphisms (SNPs) in the BCHE gene: -116G > A (rs1126680), 1615GA (rs1803274), 1914A < G (rs3495), with obesity and lipid metabolism markers, body mass index (BMI), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglyceride (TG) levels, and BChE enzymatic activity in obese (BMI≥30/n = 226) and non-obese women (BMI < 25/n = 81). BCHE SNPs genotyping was obtained by TaqMan allelic discrimination assay and by RFLP-PCR. Plasmatic BChE activity was measured using propionylthiocholine as substrate. Similar allele frequencies were found in obese and non-obese women for the three studied SNPs (p > 0.05). The dominant and recessive models were tested, and different effects were found. The -116A allele showed a dominant effect in BChE activity reduction in both non-obese and obese women (p = 0.045 and p < 0.001, respectively). The 1914A > G and 1615GA SNPs influenced the TG levels only in obese women. The 1914G and the 1615A alleles were associated with decreased plasma levels of TG. Thus, our results suggest that the obesity condition, characterized by loss of energy homeostasis, is modulated by BCHE polymorphisms.

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