scholarly journals Association between human paraoxonase 2 protein and efficacy of acetylcholinesterase inhibiting drugs used against Alzheimer’s disease

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258879
Author(s):  
Fauzia Parween ◽  
Md. Summon Hossain ◽  
Kshetra Pal Singh ◽  
Rinkoo Devi Gupta

Serum Paraoxonase 2 (PON2) level is a potential biomarker owing to its association with a number of pathophysiological conditions such as atherosclerosis and cardiovascular disease. Since cholinergic deficiency is closely linked with Alzheimer’s disease (AD) progression, acetylcholinesterase inhibitors (AChEIs) are the treatment of choice for patients with AD. However, there is a heterogenous response to these drugs and mostly the subjects do not respond to the treatment. Gene polymorphism, the simultaneous occurrence of two or more discontinuous alleles in a population, could be one of the important factors for this. Hence, we hypothesized that PON2 and its polymorphic forms may be hydrolyzing the AChEIs differently, and thus, different patients respond differently. To investigate this, two AChEIs, donepezil hydrochloride (DHC) and pyridostigmine bromide (PB), were selected. Human PON2 wildtype gene and four mutants, two catalytic sites, and two polymorphic sites were cloned, recombinantly expressed, and purified for in vitro analysis. Enzyme activity and AChE activity were measured to quantitate the amount of DHC and PB hydrolyzed by the wildtype and the mutant proteins. Herein, PON2 esterase activity and AChE inhibitor efficiency were found to be inversely related. A significant difference in enzyme activity of the catalytic site mutants was observed as compared to the wildtype, and subsequent AChE activity showed that esterase activity of PON2 is responsible for the hydrolysis of DHC and PB. Interestingly, PON2 polymorphic site mutants showed increased esterase activity; therefore, this could be the reason for the ineffectiveness of the drugs. Thus, our data suggested that the esterase activity of PON2 was mainly responsible for the hydrolysis of AChEI, DHC, and PB, and that might be responsible for the variation in individual response to AChEI therapy.

2018 ◽  
Vol 15 (7) ◽  
pp. 610-617 ◽  
Author(s):  
Huifeng Zhang ◽  
Dan Liu ◽  
Huanhuan Huang ◽  
Yujia Zhao ◽  
Hui Zhou

Background: β-amyloid (Aβ) accumulates abnormally to senile plaque which is the initiator of Alzheimer's disease (AD). As one of the Aβ-degrading enzymes, Insulin-degrading enzyme (IDE) remains controversial for its protein level and activity in Alzheimer's brain. Methods: The electronic databases PubMed, EMBASE, The Cochrane Library, OVID and Sinomed were systemically searched up to Sep. 20th, 2017. And the published case-control or cohort studies were retrieved to perform the meta-analysis. Results: Seven studies for IDE protein level (AD cases = 293; controls = 126), three for mRNA level (AD cases = 138; controls = 81), and three for enzyme activity (AD cases = 123; controls = 75) were pooling together. The IDE protein level was significantly lower in AD cases than in controls (SMD = - 0.47, 95% CI [-0.69, -0.24], p < 0.001), but IDE mRNA and enzyme activity had no significant difference (SMD = 0.02, 95% CI [-0.40, 0.43] and SMD = 0.06, 95% CI [-0.41, 0.53] respectively). Subgroup analyses found that IDE protein level was decreased in both cortex and hippocampus of AD cases (SMD = -0.43, 95% CI [-0.71, -0.16], p = 0.002 and SMD = -0.53, 95% CI [-0.91, -0.15], p = 0.006 respectively). However, IDE mRNA was higher in cortex of AD cases (SMD = 0.71, 95% CI [0.14, 1.29], p = 0.01), not in hippocampus (SMD = -0.26, 95% CI [-0.58, 0.06]). Conclusions: Our results indicate that AD patients may have lower IDE protease level. Further relevant studies are still needed to verify whether IDE is one of the factors affecting Aβ abnormal accumulation and throw new insights for AD detection or therapy.


2004 ◽  
Vol 59 (3-4) ◽  
pp. 293-296 ◽  
Author(s):  
Pavla Zdražilová ◽  
Šárka Štĕpánková ◽  
Karel Komers ◽  
Karel Ventura ◽  
Alexander Čegan

The power of chosen carbamates and hydrazinium derivatives (carbazates) to inhibit the hydrolysis of acetylthiocholine by butyrylcholinesterase or acetylcholinesterase was tested. The determined pI50 values (= negative logarithm of the molar concentration inhibiting the enzyme activity by 50%) of the tested substances were compared with pI50 values of the commercially used drugs for the Alzheimer’s disease treatment - rivastigmine and galanthamine.


2010 ◽  
Vol 6 ◽  
pp. S497-S498 ◽  
Author(s):  
Ulf Andreasson ◽  
Maria Bjerke ◽  
Johan Gobom ◽  
Oskar Hansson ◽  
Per Johansson ◽  
...  

2021 ◽  
pp. 1-12
Author(s):  
Aslina Pahrudin Arrozi ◽  
Daijiro Yanagisawa ◽  
Tomoko Kato ◽  
Hiroyasu Akatsu ◽  
Yoshio Hashizume ◽  
...  

Background: Emerging evidence indicates that the misfolded tau protein can propagate aggregates between cells in a prion-like manner. This prion activity has been typically studied in brain extracts of patients with Alzheimer’s disease (AD), but not in the olfactory region that can be a potential biomarker in AD. Objective: To investigate the prion seeding activity of tau in nasal mucosa tissues using a cell culture model of tau propagation. Methods: Brain and nasal mucosa homogenates were added to HEK293T cells expressing three repeat or four-repeat domains of tau with the L266V, V337M (3RD *VM-EGFP) and P301L and V377M mutations (4RD *LM) fused to the enhanced green fluorescence protein (EGFP) respectively. We also measured the level of phosphorylated tau (p-tau), total tau (t-tau), and p-tau/t-tau ratio and performed correlation analysis between tau prion activity and the level of tau. Results: We found that brain and nasal tissue homogenates from patients with AD significantly induced tau aggregation in HEK293T cells either expressing tau 3RD *VM-EGFP or 4RD *LM-EGFP compared with control brain and nasal tissue homogenates. The levels of p-tau and p-tau/t-tau ratio were significantly increased in the brain of patients with AD; however, no significant difference was found in nasal tissue compared with their respective control tissue homogenates. Conclusion: These results suggest that the nasal tissues contain tau seeds, similar to the brain, albeit without changes in the levels of p-tau and t-tau. Therefore, a cellular bioassay using nasal tissues would have great potential as an AD biomarker because of the usefulness of nasal tissue biopsy.


2020 ◽  
Author(s):  
Makiko Shinomoto ◽  
Takashi Kasai ◽  
Harutsugu Tatebe ◽  
Fukiko Kitani-Morii ◽  
Takuma Ohmichi ◽  
...  

Abstract Alzheimer’s disease (AD) is the most common cause of dementia. Although AD was initially considered to be a cell autonomous neurodegenerative disorder, marked neuroinflammation is observed in the brains of patients with AD, alongside Aβ and tau pathology. Based on genetic and molecular biological findings, central nervous system (CNS) inflammatory processes have been postulated to be involved in the etiopathogenesis of AD, in which activated microglia play a key role. This has also been supported by the epidemiological observation that CNS infections were associated with the development of AD, and in particular the relationship between herpetic virus and AD has been well-investigated. For example, the presence of anti-herpes simplex virus (HSV) antibody was associated with an elevated risk of developing AD [1]. Moreover, anti-herpetic medication was associated with a reduced risk of dementia in a population-based study [2]. Similar results were also observed in the case of varicella zoster virus (VZV) infections [3]. Taking into consideration the reports above, we hypothesized that the biomarker signature representing AD might be observed in patients with herpetic viral CNS infections as a prognostic biomarker of AD development. In the current study, we aimed to determine whether or not the biomarkers related to AD and neurodegeneration were changed in patients with CNS infection by HSV and VZV compared with controls. This study focused on CSF levels of Aβ1-42, Aβ1-40, total-tau (t-tau), and tau phosphorylated at threonine 181 (p-tau) as molecules representing the AD signature; neurofilament light chain (NfL) and phosphorylated neurofilament heavy chain (p-NfH) as indicators of axonal injury; soluble triggering receptor expressed on myeloid cells 2 (sTREM2) as a potential biomarker for microglia activity; and glial fibrillary acidic protein (GFAP) as a biomarker for astrocytic damage. We also measured serum levels of NfL as a blood based biomarker for axonal injury. (For detailed methods, see Supplementary methods) The demographic characteristics, diagnosis, CSF profiles, results of viral detection, magnetic resonance imaging (MRI) findings, lowest score of the Glasgow coma scale (GCS) during the hospitalization period, and modified Rankin Scale (mRS) at discharge are summarized in Supplementary Table 1 and 2. There was no significant difference in age or sex among the HSV, VZV, and control groups.


2021 ◽  
Vol 80 (2) ◽  
pp. 673-681
Author(s):  
Jin Wang ◽  
Xiaojuan Guo ◽  
Wenhui Lu ◽  
Jie Liu ◽  
Hong Zhang ◽  
...  

Background: Vascular factors and mitochondria dysfunction contribute to the pathogenesis of Alzheimer’s disease (AD). DL-3-n-butylphthalide (NBP) has an effect in protecting mitochondria and improving microcirculation. Objective: The aim was to investigate the effect of donepezil combined NBP therapy in patients with mild-moderate AD. Methods: It was a prospective cohort study. 92 mild-moderate AD patients were classified into the donepezil alone group (n = 43) or the donepezil combined NBP group (n = 49) for 48 weeks. All patients were evaluated with Alzheimer’s Disease Assessment Scale-Cognitive subscale (ADAS-cog), Clinician’s Interview-Based Impression of Change plus caregiver input (CIBIC-plus), Alzheimer’s Disease Cooperative Study-Activities of Daily Living (ADCS-ADL), and Neuropsychiatric Inventory (NPI) every 12 weeks. All patients were monitored for adverse events (AEs). The efficacy was analyzed using multivariate logistic regression analysis. Results: The multivariate logistic regression analysis showed that the changes of ADAS-cog score (OR = 2.778, 95% CI: [1.087, 7. 100], p = 0.033) and ADCS-ADL score (OR = 2.733, 95% CI: [1.002, 7.459], p = 0.049) had significant difference between donepezil alone group and donepezil combined NBP group, while the changes of NPI (OR = 1.145, 95% CI: [0.463, 2.829], p = 0.769), MMSE (OR = 1.563, 95% CI: [0.615, 3.971], p = 0.348) and CIBIC-plus (OR = 2.593, 95% CI: [0.696, 9.685], p = 0.156) had no significant difference. The occurrence of AEs was similar in the two groups. Conclusion: Over the 48-week treatment period, donepezil combined NBP group had slower cognitive decline and better activities of daily living in patients with mild to moderate AD. These indicated that the multi-target therapeutic effect of NBP may be a new choice for AD treatment.


2021 ◽  
Vol 5 (1) ◽  
pp. 49-53
Author(s):  
Steven Lehrer ◽  
Peter H. Rheinstein

Background: Cognitive problems are common in breast cancer patients. The apolipoprotein E4 (APOE4) gene, a risk factor for Alzheimer’s disease (AD), may be associated with cancer-related cognitive decline. Objective: To further evaluate the effects of the APOE4 allele, we studied a cohort of patients from the UK Biobank (UKB) who had breast cancer; some also had AD. Methods: Our analysis included all subjects with invasive breast cancer. Single nucleotide polymorphism (SNP) data for rs 429358 and rs 7412 was used to determine APOE genotypes. Cognitive function as numeric memory was assessed with an online test (UKB data field 20240). Results: We analyzed data from 2,876 women with breast cancer. Of the breast cancer subjects, 585 (20%) carried the APOE4 allele. Numeric memory scores were significantly lower in APOE4 carriers and APOE4 homozygotes than non-carriers (p = 0.046). 34 breast cancer subjects (1.1%) had AD. There was no significant difference in survival among genotypes ɛ3/ɛ3, ɛ3/ɛ4, and ɛ4/ɛ4. Conclusion: UKB data suggest that cognitive problems in women with breast cancer are, for the most part, mild, compared with other sequelae of the disease. AD, the worst cognitive problem, is relatively rare (1.1%) and, when it occurs, APOE genotype has little impact on survival.


Author(s):  
Seyedeh Nazanin Hajjari ◽  
Saeed Sadigh-Eteghad ◽  
Dariush Shanehbandi ◽  
Shahram Teimourian ◽  
Ali Shahbazi ◽  
...  

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Aidan Kenny ◽  
Eva M. Jiménez-Mateos ◽  
María Ascensión Zea-Sevilla ◽  
Alberto Rábano ◽  
Pablo Gili-Manzanaro ◽  
...  

Abstract Alzheimer’s disease (AD) is characterized by a progressive loss of neurons and cognitive functions. Therefore, early diagnosis of AD is critical. The development of practical and non-invasive diagnostic tests for AD remains, however, an unmet need. In the present proof-of-concept study we investigated tear fluid as a novel source of disease-specific protein and microRNA-based biomarkers for AD development using samples from patients with mild cognitive impairment (MCI) and AD. Tear protein content was evaluated via liquid chromatography-mass spectrometry and microRNA content was profiled using a genome-wide high-throughput PCR-based platform. These complementary approaches identified enrichment of specific proteins and microRNAs in tear fluid of AD patients. In particular, we identified elongation initiation factor 4E (eIF4E) as a unique protein present only in AD samples. Total microRNA abundance was found to be higher in tears from AD patients. Among individual microRNAs, microRNA-200b-5p was identified as a potential biomarker for AD with elevated levels present in AD tear fluid samples compared to controls. Our study suggests that tears may be a useful novel source of biomarkers for AD and that the identification and verification of biomarkers within tears may allow for the development of a non-invasive and cost-effective diagnostic test for AD.


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