scholarly journals Structure of heparan sulphate from human brain, with special regard to Alzheimer's disease

1995 ◽  
Vol 306 (1) ◽  
pp. 177-184 ◽  
Author(s):  
B Lindahl ◽  
L Eriksson ◽  
U Lindahl

Heparan sulphate (HS) was isolated after proteolytic digestion of cerebral cortex, obtained at autopsy, of patients with Alzheimer's disease (AD) and of control subjects. Deaminative cleavage in combination with selective radiolabelling procedures showed that the N-acetylated regions in the intact polysaccharides ranged from isolated residues to approximately 10 consecutive N-acetylated disaccharide units, without any apparent difference between AD and control HS. The yield of disaccharide deamination products was slightly higher with AD than with control HS, suggesting a differential distribution of N-sulphate groups. Separation of the disaccharides by anion-exchange h.p.l.c. yielded four mono-O-sulphated and one di-O-sulphated disaccharide; these components occurred in strikingly similar proportions in all cerebral HS preparations (except polysaccharide from neonatal brain) irrespective of the age of the individual and the histopathology of the cortex specimen. No significant difference was noted between HS obtained from control and from AD tissue. By contrast, the composition of HS isolated from brain differed significantly from that of HS preparations derived from other human organs.

Genetika ◽  
2013 ◽  
Vol 45 (2) ◽  
pp. 503-514 ◽  
Author(s):  
Jalal Gharesouran ◽  
Maryam Rezazadeh ◽  
Mohaddes Mojtaba

Alzheimer's disease is a complex neurodegenerative disorder characterized by memory and cognitive impairment and is the leading cause of dementia in the elderly. The aim of our study was to examine the polymorphic DNA markers CCR2 (+190 G/A), CCR5?32, TNF-? (-308 G/A), TNF-? (-863 C/A) and CALHM1 (+394 C/T) to determine the relationship between these polymorphisms and the risk of late onset Alzheimer's disease in the population of Eastern Azerbaijan of Iran. A total of 160 patient samples and 163 healthy controls were genotyped by PCR-RFLP and the results confirmed using bidirectional sequencing. Statistical analysis of obtained data revealed non-significant difference between frequency of CCR5?32 in case and control groups. The same result was observed for TNF-? (-863 C/A) genotype and allele frequencies. Contrary to above results, significant differences were detected in frequency of TNF-? (-308 G/A) and CCR2-64I genotypes between the cases and healthy controls. A weak significant difference observed between allele and genotype frequencies of rs2986017 in CALHM1 (+394 C/T; P86L) in patient and control samples. It can be concluded that the T allele of P86L variant in CALHM1 & +190 G/A allele of CCR2 have a protective role against abnormal clinical features of Alzheimer's disease.


2020 ◽  
Vol 83 (4) ◽  
pp. 395-403
Author(s):  
Ritsuo Hashimoto ◽  
Momoko Uechi ◽  
Noriyo Komori

Background: Topographical disorientation is one of the early symptoms of Alzheimer’s disease (AD). The nature of this symptom, however, remains unclear. Objective: The aim of the study was to investigate egocentric and allocentric spatial cognition in patients with amnestic mild cognitive impairment (aMCI) and early AD. Participants and Methods: The participants consisted of normal healthy volunteers (n = 23), patients with aMCI (n = 26), and patients with early AD (n = 22). We administered the card placing test (CPT), in which a subject was required to recreate an array of 3 cards, each of which was randomly placed on 8 grids around the individual, before (part A) and after (part B) the individual’s rotation. With this design, the CPT can reveal an individual’s ability to represent spatial information either egocentrically (CPT-A) or allocentrically (CPT-B). A qualitative analysis of errors in performing the CPT was also conducted. Results: Compared with the controls, the aMCI patients showed significantly poorer CPT-B performance, while there was no significant difference in CPT-A performance between these 2 groups. In contrast, the AD patients demonstrated significantly poorer performance on both the CPT-A and CPT-B than the controls and aMCI patients. There was no significant difference in the profile of errors on the CPT-B between the controls and aMCI patients, whereas there was a notable difference in those on the CPT-A between the controls and AD patients and the aMCI and AD patients. Conclusion: Allocentric spatial cognition is selectively impaired in aMCI patients, while an egocentric spatial cognition is additionally impaired in AD patients.


2020 ◽  
Vol 10 (1) ◽  
pp. 44
Author(s):  
Eva Mª Arroyo-Anlló ◽  
Corinne Souchaud ◽  
Pierre Ingrand ◽  
Jorge Chamorro Sánchez ◽  
Alejandra Melero Ventola ◽  
...  

Alexithymia is widely recognized as the inability to identify and express emotions. It is a construct which consists of four cognitive traits such as difficulty in identifying feelings, describing feelings to others, externally oriented thinking, and limited imaginative capacity. Several studies have linked alexithymia to cognitive functioning, observing greater alexithymia scores associated with poorer cognitive abilities. Despite Alzheimer’s disease (AD) being a neurodegenerative pathology characterized by cognitive troubles from the early stages, associated to behavioral and emotional disturbances, very few investigations have studied the alexithymia in AD. These studies have shown that alexithymia scores—assessed with Toronto Alexithymia Scale (TAS)—were greater in AD patients than healthy participants. The objective of the study was to investigate if the alexithymia was present in patients with mild AD. We hypothesized that the AD group would show more alexithymia features than the control group. We evaluated 54 subjects, including 27 patients diagnosed with mild AD and 27 normal healthy controls, using the Shalling Sifneos Psychosomatic Scale (SSPS-R) and a neuropsychological test battery. Using non-parametric statistical analyses—Wilcoxon and Mann–Whitney U tests—we observed that the SSPS-R scores were similar in the AD and control groups. All participants showed SSPS-R scores below to 10 points, which means no-alexithymia. We did not find significant correlations between SSPS-R scores and cognitive variables in both groups (p > 0.22), but we observed a negative association between name abilities and alexithymia, but it does not reach to significance (p = 0.07). However, a significant correlation between SSPS-R score and mood state, assessed using Zerssen Rating Scale, was found in both groups (p = 0.01). Because we did not find a significant difference in the alexithymia assessment between both subject groups, pot hoc analyses were computed for each item of the SSPS-R. We made comparisons of alexithymic responses percentages in each SSPS-R item between AD and control groups, using Fisher’s test. We observed that AD patients produced more alexithymic responses in some items of SSPS-R test than the control group, particularly about difficulties to find the words to describe feelings, as well as difficulties of imagination capacity and externally oriented thinking. The present results do not confirm our hypothesis and they do not support the results of previous studies revealing great alexithymia in AD.


Author(s):  
Gholamhasan Jafarzadeh ◽  
Asieh Sadat Mousavian ◽  
Saeid Shakerian

Objectives: This study aimed to evaluate the impact of resistance exercise and donepezil on some neurotrophins gene expression and Trk receptors in the hippocampus of rats with Alzheimer’s disease (AD). Methods: In this study, 32 male adult Wistar rats (mean weight: 230 - 280 g) were assigned into two groups of AD and control. The control and AD groups received normal saline and streptozotocin (STZ) through intraventricular injection, respectively. Then, six subgroups were considered: (1) control rest (Con); (2) control exercise (Con-Exe); (3) Alzheimer’s rest (Alz); (4) Alzheimer’s exercise (Alz-Exe); (5) Alzheimer’s donepezil (Alz-Don); and (6) Alzheimer’s donepezil-exercise (Alz-Don-Exe). Donepezil was fed daily at a dose of 1.5 mg/kg to the treated groups. The three subgroups of exercising rats received exercises for eight weeks (three times a week). Each day, the resting groups were managed to decrease stress impacts. Twenty-four hours after the last session of exercise by the eighth week, deep anesthesia was applied, and the rats' heads were severed. Results: Considering an error rate below 5% (P < 0.05) and a confidence of more than 95%, a significant difference was observed in BDNF, NT3, NGF, TrkA, and TrkB values between exercising and donepezil-exercise rats compared to AD group. These values were considerably greater for donepezil-exercising Alzheimer’s group. Besides, the donepezil group was not significantly different from the Alzheimer’s group. Conclusions: Although the use of donepezil alone did not significantly increase the expression of the studied genes, the concomitant use of the drug and resistance training significantly increased the expression levels.


2021 ◽  
Vol 72 (2) ◽  
pp. 5-10
Author(s):  
Violeta Jovanović ◽  
Jelica Despotović ◽  
Mario Balo ◽  
Ivan Zaletel ◽  
Sanja Despotović ◽  
...  

Introduction: Alzheimer's disease is the most common neurodegenerative disorder, characterized by the formation of amyloid plaques and the neurofibrillary tangles in the brain of an ill person, leading to neuronal damage and loss. Activation of astrocytes and astrogliosis occurs along with this process. Due to ethical limitations in working with human tissue, numerous transgenic animal models have been developed to study the pathogenesis of these processes. Early Ab deposition is observed in the cortex and the hippocampus. Aim: This study aimed to determine the difference in the presence of GFAP positive cells in the hippocampus between transgenic 5xFAD mice aged 36 weeks and their corresponding controls. Material and Methods: The 5xFAD mice model of Alzheimer's disease was used, characterized by early formation of amyloid plaques but without the presence of neurofibrillar tangles. Transgenic and control animals were sacrificed at 36 weeks of age. The visualization of GFAP-positive cells in the hippocampus of their brains was done by using immunohistochemistry and antibody for glial fibrillary acidic protein - GFAP, the major marker of astrocytes. Quantification of immuno-reactivity was done by using the Icy software system. Results: There was a statistically significant difference in the expression of GFAP in the dentate gyrus and the granular zone of the hippocampus between the transgenic and control group at 36 weeks of age, while the significant change in the CA1-3 regions was not observed between investigated groups. Conclusion: Obtained results confirm the involvement of astrogliosis in the pathophysiology of Alzheimer's disease and indicate an earlier occurrence of astrogliosis in the dentate gyrus and granular zone, in relation to other regions of the hippocampus, in the 36-week-old 5xFAD mice.


Author(s):  
Burbaeva G.Sh. ◽  
Androsova L.V. ◽  
Vorobyeva E.A. ◽  
Savushkina O.K.

The aim of the study was to evaluate the rate of polymerization of tubulin into microtubules and determine the level of colchicine binding (colchicine-binding activity of tubulin) in the prefrontal cortex in schizophrenia, vascular dementia (VD) and control. Colchicine-binding activity of tubulin was determined by Sherlinе in tubulin-enriched extracts of proteins from the samples. Measurement of light scattering during the polymerization of the tubulin was carried out using the nephelometric method at a wavelength of 450-550 nm. There was a significant decrease in colchicine-binding activity and the rate of tubulin polymerization in the prefrontal cortex in both diseases, and in VD to a greater extent than in schizophrenia. The obtained results suggest that not only in Alzheimer's disease, but also in other mental diseases such as schizophrenia and VD, there is a decrease in the level of tubulin in the prefrontal cortex of the brain, although to a lesser extent than in Alzheimer's disease, and consequently the amount of microtubules.


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.


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 13 (1) ◽  
Author(s):  
Adeline Su Lyn Ng ◽  
Juan Wang ◽  
Kwun Kei Ng ◽  
Joanna Su Xian Chong ◽  
Xing Qian ◽  
...  

Abstract Background Alzheimer’s disease (AD) and behavioral variant frontotemporal dementia (bvFTD) cause distinct atrophy and functional disruptions within two major intrinsic brain networks, namely the default network and the salience network, respectively. It remains unclear if inter-network relationships and whole-brain network topology are also altered and underpin cognitive and social–emotional functional deficits. Methods In total, 111 participants (50 AD, 14 bvFTD, and 47 age- and gender-matched healthy controls) underwent resting-state functional magnetic resonance imaging (fMRI) and neuropsychological assessments. Functional connectivity was derived among 144 brain regions of interest. Graph theoretical analysis was applied to characterize network integration, segregation, and module distinctiveness (degree centrality, nodal efficiency, within-module degree, and participation coefficient) in AD, bvFTD, and healthy participants. Group differences in graph theoretical measures and empirically derived network community structures, as well as the associations between these indices and cognitive performance and neuropsychiatric symptoms, were subject to general linear models, with age, gender, education, motion, and scanner type controlled. Results Our results suggested that AD had lower integration in the default and control networks, while bvFTD exhibited disrupted integration in the salience network. Interestingly, AD and bvFTD had the highest and lowest degree of integration in the thalamus, respectively. Such divergence in topological aberration was recapitulated in network segregation and module distinctiveness loss, with AD showing poorer modular structure between the default and control networks, and bvFTD having more fragmented modules in the salience network and subcortical regions. Importantly, aberrations in network topology were related to worse attention deficits and greater severity in neuropsychiatric symptoms across syndromes. Conclusions Our findings underscore the reciprocal relationships between the default, control, and salience networks that may account for the cognitive decline and neuropsychiatric symptoms in dementia.


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.


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