Although the ε2 allele of apolipoprotein E ( APOE2 ) benefits longevity, its mechanism is not understood. The protective effects of the APOE 2 on Alzheimer’s disease (AD) risk, particularly through their effects on amyloid or tau accumulation, may confound APOE2 effects on longevity. Herein, we showed that the association between APOE2 and longer lifespan persisted irrespective of AD status, including its neuropathology, by analyzing clinical datasets as well as animal models. Notably, APOE2 was associated with preserved activity during aging, which also associated with lifespan. In animal models, distinct apoE isoform levels, where APOE2 has the highest, were correlated with activity levels, while some forms of cholesterol and triglycerides were associated with apoE and activity levels. These results indicate that APOE2 can contribute to longevity independent of AD. Preserved activity would be an early-observable feature of APOE2 -mediated longevity, where higher levels of apoE2 and its-associated lipid metabolism might be involved.
Mitophagy alterations in Alzheimer's disease are associated with granulovacuolar degeneration and early tau pathology
Abstract Introduction The cytoprotective PTEN‐induced kinase 1 (PINK1)‐parkin RBR E3 ubiquitin protein ligase (PRKN) pathway selectively labels damaged mitochondria with phosphorylated ubiquitin (pS65‐Ub) for their autophagic removal (mitophagy). Because dysfunctions of mitochondria and degradation pathways are early features of Alzheimer's disease (AD), mitophagy impairments may contribute to the pathogenesis. Methods Morphology, levels, and distribution of the mitophagy tag pS65‐Ub were evaluated by biochemical analyses combined with tissue and single cell imaging in AD autopsy brain and in transgenic mouse models. Results Analyses revealed significant increases of pS65‐Ub levels in AD brain, which strongly correlated with granulovacuolar degeneration (GVD) and early phospho‐tau deposits, but were independent of amyloid beta pathology. Single cell analyses revealed predominant co‐localization of pS65‐Ub with mitochondria, GVD bodies, and/or lysosomes depending on the brain region analyzed. Discussion Our study highlights mitophagy alterations in AD that are associated with early tau pathology, and suggests that distinct mitochondrial, autophagic, and/or lysosomal failure may contribute to the selective vulnerability in disease.
Variants inPPP2R2BandIGF2BP3are associated with higher tau deposition
AbstractTau deposition is a key biological feature of Alzheimer’s disease that is closely related to cognitive impairment. However, it remains poorly understood why certain individuals may be more susceptible to tau deposition while others are more resistant. The recent availability of in vivo assessment of tau burden through positron emission tomography provides an opportunity to test the hypothesis that common genetic variants may influence tau deposition. We performed a genome-wide association study of tau-positron emission tomography on a sample of 754 individuals over age 50 (mean age 72.4 years, 54.6% men, 87.6% cognitively unimpaired) from the population-based Mayo Clinic Study of Aging. Linear regression was performed to test nucleotide polymorphism associations with AV-1451 (18F-flortaucipir) tau-positron emission tomography burden in an Alzheimer’s-signature composite region of interest, using an additive genetic model and covarying for age, sex and genetic principal components. Genome-wide significant associations with higher tau were identified for rs76752255 (P = 9.91 × 10−9, β = 0.20) in the tau phosphorylation regulatory gene PPP2R2B (protein phosphatase 2 regulatory subunit B) and for rs117402302 (P = 4.00 × 10−8, β = 0.19) near IGF2BP3 (insulin-like growth factor 2 mRNA-binding protein 3). The PPP2R2B association remained genome-wide significant after additionally covarying for global amyloid burden and cerebrovascular disease risk, while the IGF2BP3 association was partially attenuated after accounting for amyloid load. In addition to these discoveries, three single nucleotide polymorphisms within MAPT (microtubule-associated protein tau) displayed nominal associations with tau-positron emission tomography burden, and the association of the APOE (apolipoprotein E) ɛ4 allele with tau-positron emission tomography was marginally nonsignificant (P = 0.06, β = 0.07). No associations with tau-positron emission tomography burden were identified for other single nucleotide polymorphisms associated with Alzheimer’s disease clinical diagnosis in prior large case–control studies. Our findings nominate PPP2R2B and IGF2BP3 as novel potential influences on tau pathology which warrant further functional characterization. Our data are also supportive of previous literature on the associations of MAPT genetic variation with tau, and more broadly supports the inference that tau accumulation may have a genetic architecture distinct from known Alzheimer’s susceptibility genes, which may have implications for improved risk stratification and therapeutic targeting.
A Retrospective Analysis of Gender-Based Difference in Adherence to Influenza Vaccination during the 2018-2019 Season
Introduction: Improving flu vaccination rates in the general population is an important and effective strategy toward reducing morbidity, mortality, and the cost of seasonal influenza. In order to optimize immunization strategies, factors associated with decreased vaccination rates need to be explored. The literature suggests that there is a gender difference in the rate of influenza vaccination but is limited to population-based survey studies and also is inconsistent as to which gender has a higher rate of vaccination. The purpose of this study was to evaluate for a gender-based difference in the rate of influenza vaccination among patients who presented for an annual physical examination during the 2018 to 2019 influenza season. Methods: In this multi-site, retrospective chart review, a total of 1193 patients (608 female and 585 male) who underwent an annual physical examination in April of 2019 were included. Baseline medical information was collected, as well as demographic characteristics and influenza vaccination status. The proportion of patients who underwent influenza vaccination was compared between males and females using multivariable logistic regression models; odds ratios (ORs) were estimated. Results: The likelihood of influenza vaccination was significantly higher in females (62.8%) compared to males (53.2%) in both unadjusted analysis (OR = 1.49, P < .001) and in multivariable analysis adjusting for the potential confounding influences of clinic location, BMI, insurance type, and occupation (OR = 1.42, P = .005). Interestingly, a higher influenza vaccination rate for females compared to males was observed in patients age<60 years (OR = 1.70, P = .025) and between ages 60 and 75 (OR = 1.66, P = .009), but not for patients older than 75 years (OR = 1.12, P = .66). Conclusion: Our findings indicate that the rate of influenza vaccination is higher for females than for males who presented for an annual preventive physical exam and who are younger than 75 years old.
Abstract 4635: Analysis of post-partum breast tissue to understand early onset breast cancer
Abstract Background: Parity reduces risk of late onset breast cancer (BC), but childbirth is associated with a transient rise in BC risk. In a prior analysis of normal breast tissues donated for research to the Komen Tissue Bank (KTB), we reported that numbers of lobules (the primary structures from which BCs arise) are increased among parous versus nulliparous women. To further define the histological features that may be related to the transient rise in post-partum BC risk, we performed an expanded histologic review of 757 breast tissues donated to the KTB by women ≤45 years of age and compared lobule number, acinar count per lobule, and abundance of immune cells, and specifically plasma cells, between nulliparous and parous women. Methods: We assessed digital scans of H&E stained tissue sections of KTB tissues for total number of lobules, and evaluated acini / lobule (ordinal categories) and lobule span (um) for ≤10 lobules per section. Masked to epidemiologic data, we subjectively assessed images including ≥5 lobules for the presence of benign breast disease (BBD), ≥3 plasma cells per section and increased immune cells in lobules. We compared parous women according to time since last birth (≤5 years or >5 years) to nulliparas (referent) using age-adjusted regression models appropriate for data type (count, continuous, ordinal, or categorical). Results: Compared to nulliparous women, parous women ≤5 years of a birth had a 1.83-fold increase in lobule counts (95% confidence interval [CI]: 1.47-2.28, P<0.001), increased plasma cells in lobules (OR=1.86; 95% CI: 1.08-3.18, P<0.025), and subjectively, increased immune cells in lobules (OR=2.46, 95% CI: 1.39-4.36, P<0.002). Comparisons of parous women ≥5 years post-partum to nulliparas revealed a 1.83-fold increase in numbers of lobules (95% CI: 1.42-2.36, P<0.001); however, lobule span in parous women was 0.89 times that of nulliparous women (95% CI: 0.80-0.99, P=0.037) and other features assessed did not show statistically significant differences. Conclusion: Histologically, normal breast tissues reveal persistently increased lobule counts and increased plasma cells and inflammation for ≤5 years post-partum compared with nulliparous women, although other lobular features decrease between ≤5 and >5 years after a birth. Future molecular studies will define how these changes in the epithelium and microenvironment during the post-partum period may inform mechanisms that mediate the transient increase in BC risk after childbirth and the reduction in BC risk that occurs later in life. Citation Format: Joshua Ogony, DereK C. Radisky, Amy C. Degnim, Marlene Frost, Tanya L. Hoskin, Michael G. Heckman, Launia J. White, Mark E. Sherman. Analysis of post-partum breast tissue to understand early onset breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4635.
Proton-pump-inhibitor use associated with lower short-term rebleeding and mortality in patients receiving esophageal variceal band ligation: a retrospective cohort study
Background The impact of proton-pump inhibitor (PPI) therapy on subsequent hemorrhage and mortality after variceal hemorrhage is unclear. Aim Evaluate the associations of PPI use with upper gastrointestinal bleeding (UGIB) and death within 30 days of undergoing esophageal variceal band ligation (EBL) separately in inpatient and outpatient settings. Methods Retrospective review of cirrhotic patients with variceal hemorrhage who underwent EBL between 2005 and 2018. Endoscopic findings, PPI use at admission (inpatients only), PPI use at discharge (inpatients and outpatients), and adverse outcomes data (liver transplant, UGIB, transjugular intrahepatic portosystemic shunt, and death within 30 days of discharge or death during hospitalization) were reviewed. Results A total of 446 patients (164 inpatients, 282 outpatients) were included. The most commonly observed outcomes were death within 30 days of discharge in inpatients (12.8%), UGIB within 30 days of discharge in inpatients (21.3%), and UGIB within 30 days of discharge in outpatients (8.5%). For inpatients, prescription of PPI at discharge was associated with a lower risk of bleeding within 30 days (odds ratio: 0.30, P = 0.025) and death within 30 days (odds ratio = 0.16, P = 0.002). No other significant associations of PPI with death or UGIB were reported. Conclusion Post-EBL PPI therapy is associated with reduced risk of bleeding and death within 30 days after variceal hemorrhage in hospitalized patients.
Tau and apolipoprotein E modulate cerebrovascular tight junction integrity independent of cerebral amyloid angiopathy in Alzheimer's disease
AbstractIntroductionCerebrovascular pathologies including cerebral amyloid angiopathy (CAA) and blood‐brain barrier (BBB) dysregulation are prominent features in the majority of Alzheimer's disease (AD) cases.MethodsWe performed neuropathologic and biochemical studies on a large, neuropathologically confirmed human AD cohort (N = 469). Amounts of endothelial tight junction proteins claudin‐5 (CLDN5) and occludin (OCLN), and major AD‐related molecules (amyloid beta [Aβ40], Aβ42, tau, p‐tau, and apolipoprotein E) in the temporal cortex were assessed by ELISA.ResultsHigher levels of soluble tau, insoluble p‐tau, and apolipoprotein E (apoE) were independently correlated with lower levels of endothelial tight junction proteins CLDN5 and OCLN in AD brains. Although high Aβ40 levels, APOE ε4, and male sex were predominantly associated with exacerbated CAA severity, those factors did not influence tight junction protein levels.DiscussionRefining the molecular mechanisms connecting tau, Aβ, and apoE with cerebrovascular pathologies is critical for greater understanding of AD pathogenesis and establishing effective therapeutic interventions for the disease.
Association of
MAPT
subhaplotypes with clinical and demographic features in Parkinson’s disease
Abstract Objective To determine whether distinct microtubule‐associated protein tau MAPT H1 subhaplotypes are associated with clinical and demographic features in Parkinson’s disease. Methods A retrospective cohort study included 855 unrelated Caucasian patients with Parkinson’s disease who were seen by Movement Disorder specialists at the Mayo Clinic Florida between 1998 and 2016. The primary outcome measures were specific demographic and clinical features of Parkinson’s disease, including age at onset, disease progression, survival, motor signs, dementia, dystonia, dyskinesia, autonomic dysfunction, impulse control disorder, psychiatric features, REM sleep behavior disorder, restless legs syndrome, and Parkinson’s disease subtype. Specific clinical features were measured at the initial visit and most recent visit. These outcomes were assessed for association with MAPT H1 subhaplotypes, which were defined by six haplotype tagging variants. Results Median onset age was 64 years (range: 22‐94 years); 548 (64%) of patients were male. Significant associations ( P < 0.0029) were observed between MAPT H1b and orthostatic hypotension (OR = 1.72, P = 0.001); between H1j and rest tremor (OR = 0.15; P < 0.001) as well as REM sleep behavior disorder (OR = 3.87, P < 0.001); between H1r and bradykinesia (OR = 0.11; P < 0.001); and between H1v and restless legs syndrome (OR = 4.02, P = 0.002). Interpretation Four MAPT H1 subhaplotypes, but not the H2 haplotype, were significantly associated with specific clinical features in Parkinson’s disease. MAPT haplotypic structure may explain some of the phenotypic variability in disease. Replication of our findings will be critical to fully resolve the Parkinson’s disease risk association signal at Chr17q21.