Current Alzheimer Research - Volume 19, Issue 13, 2022

Amyloid plaques and neurofibrillary tangles are two main characteristics of Alzheimer’s disease (AD). As cerebral resident phagocytes, microglia have different roles in Aβ pathology and tau pathology. In this review, we discuss microglial functions in the formation, clearance, and spread of Aβ and tau. Many receptors and enzymes, which are related to microglia, participate in AD pathologies and thus are thought to be potential targets of AD. So, making use of microglia can be beneficial to confine AD pathologies. To sum up, this article review the roles of microglia in AD pathology and possible corresponding treatments.

Background: In most patients with frontotemporal lobe degeneration (FTLD), the degenerative process begins between the ages 45 and 65 years; onset younger than 45 years is relatively rare and considered very early onset FTLD (VEO-FTLD). Objective: To delineate the clinical, genetic, and pathological features of VEO-FTLD. Methods: A systematic literature review was carried out in PubMed and Embase from inception to September 2021. Patients diagnosed with definite FTLD with onset before age 45 years were included. Patients lacking detailed clinical data or both genetic and neuropathological data were excluded. Phenotypic, genotypic, and pathological data were extracted for further analyses. Results: Data from 110 patients with VEO-FTLD, reported in a cumulative 70 publications, were included. Age of onset was 35.09 ± 7.04 (14-44) years. Sixty-seven patients were reported age at death of 42.12 ± 7.26 (24–58) years, with a disease course lasting 8.13 ± 4.69 (1–20) years. Behavioural variant frontotemporal dementia (104/110, 94.5%) was the most common clinical subtype, often manifesting as disinhibition (81.8%) and apathy (80.9%), and frequently accompanied by a cognitive deficit (90.9%) and parkinsonism (37.3%). Frequency of familial aggregation was high (familial vs. sporadic, 73/37, 66.4%); most patients carried MAPT gene mutations (72.9% in familial, 40% in sporadic), followed by C9 (18.8% in familial, 10% in sporadic), TARDBP (2.1% in familial), and VCP (2.1% in familial). The most common neuropathology subtype was tau (43.5%), followed by ubiquitin- positive (24.6%), FUS (20.3%), and TDP 43 (2.9%). Conclusion: VEO-FTLD may have unique clinical, genetic, and neuropathological markers and should be considered in young patients with psycho-behavioral symptoms.

Background: Caring for an individual with Alzheimer’s disease (AD) is an allencompassing challenge that affects daily life. Assessment of the care partner experience is needed to support the development and evaluation of successful interventions for people with AD and their care partners. We developed the 27-item Zarit Caregiver Interview for Alzheimer’s Disease (ZCI-AD-27) to assess the impact of informal caregiving in the context of AD. Objective: We assessed the psychometric validity of the ZCI-AD-27 in a population of care partners for individuals with moderate AD, and established thresholds for meaningful score change. Methods: Secondary data were obtained from informal care partners of participants in a clinical trial (NCT01677754). Psychometric analyses were conducted to assess validity, reliability, and responsiveness of the ZCI-AD-27. Anchor-based and distribution-based methods were performed to determine clinically meaningful score change. Results: The ZCI-AD-27 had a 12-domain factor structure, including a second-order domain termed Humanistic impact that included four key domains (Physical, Emotional, Social, and Daily life) as confirmed by confirmatory factor analysis with the adequate fit. Internal consistency (Cronbach’s alpha ranging from 0.66 to 0.93 for domains), convergent validity, and discriminant validity indicated the good performance of the ZCI-AD-27. Known-groups validity analyses showed a greater impact on care partners with increasing disease severity. Responsiveness results demonstrated that the ZCI-AD- 27 is sensitive to change over time and meaningful change analyses indicated a range of meaningful score changes in this population. Conclusion: The ZCI-AD-27 is a comprehensive, psychometrically valid measure to assess the impact of caring for individuals with moderate AD.

Aim / Objective: This study aimed to investigate the levels of organochlorine pesticides (OCPs) in the serum of Alzheimer's disease (AD) patients. Methods: 63 AD patients and 50 healthy individuals participated, and the levels of some OCPs derivatives (including; α-HCH, β-HCH, γ-HCH, 2,4-DDT, 4,4-DDT, 2,4-DDE, and 4,4-DDE), total antioxidant capacity (TAC), protein carbonyl (PC), malondialdehyde (MDA), Nitric oxide (NO) along with the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), paraoxonase 1(PON1), and acetylcholinesterase (AChE) were measured. Results: The mean OCP level of OCPs in AD patients was significantly higher than in the control group. However, the patients' mean levels of TAC, PC, MDA and activity of SOD, GPx, PON1 and AChE were significantly lower than controls. A significant positive correlation was also observed between 2,4-DDE and MDA and between γ-HCH and PC in AD patients. These findings showed that pesticide exposure is associated with an increased risk of AD. Furthermore, the mean levels of oxidative stress markers, which may result from pesticide exposure, were significantly lower in AD patients compared to healthy individuals. Conclusion: Therefore, it may conclude that pesticides, at least in part, contribute to AD development through several mechanisms, including the induction of oxidative stress.