BuChE K variant is decreased in Alzheimer's disease not in fronto-temporal dementia.

Institute of Neurology, Catholic University of Sacred Heart, Rome, Italy.
Journal of Neural Transmission (Impact Factor: 2.87). 03/2010; 117(3):377-83. DOI: 10.1007/s00702-009-0358-y
Source: PubMed

ABSTRACT Alzheimer's disease (AD) is characterized by a significant reduction in AcetylCholinesterase and an increase in ButyrylCholinesterase (BuChE) activity. The existence of polymorphic regions on the BuChE gene has been previously described; the most frequently found polymorphism is the so-called K variant, which leads to a 30% decreased enzymatic activity. Different studies reported a positive association between K variant and AD, strongest among late-onset AD and Apolipoprotein E (APOE) e4 carriers. We analyzed APOE and BuChE polymorphisms in 167 AD and 59 fronto-temporal dementia (FTD) patients compared with 129 healthy controls (HC). We reported a significantly lower frequency of the BuChE K variant in AD compared with HC and FTD and a significant increased frequency of the K variant in FTD. These results are in agreement with the known increase of the BuChE activity in AD and support the evidence of different molecular pathways involved in the pathogenesis of AD and FTD.

  • [Show abstract] [Hide abstract]
    ABSTRACT: The extensive neuroprotective effects of estrogen against Alzheimer's disease (AD) have been proven in numerous laboratory studies. However, in clinical studies, the exact role of estrogen in AD is still ambiguous. Some evidences even suggested the high levels of estrogen or estrogen replacement treatment increased the risk of AD. Thus, there must be other factors affecting the neuroprotective effects of estrogen. Multiple enzymes and receptor proteins are involved in the biosynthesis, metabolism and signaling pathways of estrogen, and mediate the beneficial effects of estrogen on AD. Previous studies have suggested some polymorphisms of genes encoding these enzymes and proteins are associated with the risk of AD. In addition to the genes associated with estrogen biosynthesis and metabolism and the genes encoding estrogen receptor proteins, some other genes also modulate the effects of estrogen on AD, or interact with other estrogen-associated genes on the progress of AD. The gene-hormone and gene-gene interactions may be key to unraveling the conflicting results regarding the effect of estrogen on AD. In this paper, we will review and discuss the associations between polymorphisms of these genes and their interactions and the susceptibility to AD. A better understanding of these estrogen-associated genes is significant to explore the pathogenesis of AD.
    Progress in Neurobiology 10/2013; 111. DOI:10.1016/j.pneurobio.2013.09.006 · 10.30 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Butyrylcholinesterase (BChE) is an enzyme expressed in multiple organs and abundant in plasma. BChE can fluctuate in course of several reasons while both hypercholiensterasemia and hypocholinesterasemia are known. Considering evidence of BChE activity alterations, hepatocellular carcinoma, chronic liver diseases and poisoning with carbamates or organophosphates can be diagnosed by activity assay. BChE is responsible for detoxification reactions, and the compounds such as cocaine, succinylcholine, and acetylsalicylic acid are degraded in the body. The detoxification can be slowed in patients carrying the K variant of the enzyme. Summarization of literature, discussion on the meaning of BChE in the body, and the principles of BChE assay in samples are described in the review (Tab. 2, Fig. 8, Ref. 86). Keywords: butyrylcholinesterase; acetylcholinesterase; liver function test; organophosphate; carbamate; poisoning; dibucaine number; Alzheimer´s disease; BChE; AChE; K variant.
    Bratislavske lekarske listy 01/2013; 114(12):726-734. DOI:10.4149/BLL_2013_153 · 0.45 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Alzheimer's disease (AD) is a neurodegenerative disorder in which there is a decline of cholinergic function. The symptomatic AD treatment involves the use of ChEIs (cholinesterase inhibitors) as rivastigimine, a dual inhibitor. The human butyrylcholinesterase (BChE) is an enzyme that has specific roles in cholinergic neurotransmission and it has been associated with AD. In the serum, BChE is found in four main molecular forms: G1 (monomer); G1-ALB (monomer linked to albumin); G2 (dimer); and G4 (tetramer). The interaction between the products of BCHE gene and CHE2 locus results in CHE2 C5+ and CHE2 C5- phenotypes. CHE2 C5+ phenotype and BChE-K are factors that influence on BChE activity. This work aimed to verify the proportions of BChE molecular forms, total and relative activity in 139 AD patients and 139 elderly controls, taking into account K variant, CHE2 locus, rivastigmine treatment and clinical dementia rating (CDR) of AD patients. Phenotypic frequencies of CHE2 C5+ and frequency of the carriers of the K allele were similar between groups. Total BChE activity in plasma was significantly lower in AD patients than in elderly controls. Furthermore, we found that reduction on plasma BChE activity is associated directly with AD progression in AD patients and that rivastigmine treatment has stronger effect in BChE activity within CDR2 group. The reduction in BChE activity did not occur proportionally in all molecular forms. Multiple regression analysis results confirmed that AD acts as main factor in plasma BChE activity reduction and that severe stages are related with an even greater reduction. These findings suggest that the reduction of total plasma BChE and relative BChE molecular forms activity in AD patients is probably associated with a feedback mechanism and provides a future perspective of using this enzyme as a possible plasmatic secondary marker for AD.
    Neurochemistry International 01/2015; 81. DOI:10.1016/j.neuint.2014.12.009 · 2.65 Impact Factor