A Lignin Molecular Brace Controls Precision Processing of Cell Walls Critical for Surface Integrity in Arabidopsis.

The cell wall, a defining feature of plants, provides a rigid structure critical for bonding cells together. To overcome this physical constraint, plants must process cell wall linkages during growth and development. However, little is known about the mechanism guiding cell-cell detachment and cell wall remodeling. Here, we identify two neighboring cell types in Arabidopsis that coordinate their activities to control cell wall processing, thereby ensuring precise abscission to discard organs. One cell type produces a honeycomb structure of lignin, which acts as a mechanical "brace" to localize cell wall breakdown and spatially limit abscising cells. The second cell type undergoes transdifferentiation into epidermal cells, forming protective cuticle, demonstrating de novo specification of epidermal cells, previously thought to be restricted to embryogenesis. Loss of the lignin brace leads to inadequate cuticle formation, resulting in surface barrier defects and susceptible to infection. Together, we show how plants precisely accomplish abscission.

EMT: 2016.

The significant parallels between cell plasticity during embryonic development and carcinoma progression have helped us understand the importance of the epithelial-mesenchymal transition (EMT) in human disease. Our expanding knowledge of EMT has led to a clarification of the EMT program as a set of multiple and dynamic transitional states between the epithelial and mesenchymal phenotypes, as opposed to a process involving a single binary decision. EMT and its intermediate states have recently been identified as crucial drivers of organ fibrosis and tumor progression, although there is some need for caution when interpreting its contribution to metastatic colonization. Here, we discuss the current state-of-the-art and latest findings regarding the concept of cellular plasticity and heterogeneity in EMT. We raise some of the questions pending and identify the challenges faced in this fast-moving field.

Organ aging signatures in the plasma proteome track health and disease.

Animal studies show aging varies between individuals as well as between organs within an individual1-4, but whether this is true in humans and its effect on age-related diseases is unknown. We utilized levels of human blood plasma proteins originating from specific organs to measure organ-specific aging differences in living individuals. Using machine learning models, we analysed aging in 11 major organs and estimated organ age reproducibly in five independent cohorts encompassing 5,676 adults across the human lifespan. We discovered nearly 20% of the population show strongly accelerated age in one organ and 1.7% are multi-organ agers. Accelerated organ aging confers 20-50% higher mortality risk, and organ-specific diseases relate to faster aging of those organs. We find individuals with accelerated heart aging have a 250% increased heart failure risk and accelerated brain and vascular aging predict Alzheimer's disease (AD) progression independently from and as strongly as plasma pTau-181 (ref. 5), the current best blood-based biomarker for AD. Our models link vascular calcification, extracellular matrix alterations and synaptic protein shedding to early cognitive decline. We introduce a simple and interpretable method to study organ aging using plasma proteomics data, predicting diseases and aging effects.

Blood-Based Proteomics for Adult-Onset Focal Dystonias.

OBJECTIVES: The adult-onset focal dystonias are characterized by over-active muscles leading to abnormal movements. For most cases, the etiology and pathogenesis remain unknown. In the current study, unbiased proteomics methods were used to identify potential changes in blood plasma proteins. METHODS: A large-scale unbiased proteomics screen was used to compare proteins (N = 6,345) in blood plasma of normal healthy controls (N = 49) with adult-onset focal dystonia (N = 143) consisting of specific subpopulations of cervical dystonia (N = 45), laryngeal dystonia (N = 49), and blepharospasm (N = 49). Pathway analyses were conducted to identify relevant biological pathways. Finally, protein changes were used to build a prediction model for dystonia. RESULTS: After correction for multiple comparisons, 15 proteins were associated with adult-onset focal dystonia. Subgroup analyses revealed some proteins were shared across the dystonia subgroups while others were unique to 1 subgroup. The top biological pathways involved changes in the immune system, metal ion transport, and reactive oxygen species. A 4-protein model showed high accuracy in discriminating control individuals from dystonia cases [average area under the curve (AUC) = 0.89]. INTERPRETATION: These studies provide novel insights into the etiopathogenesis of dystonia, as well as novel potential biomarkers. ANN NEUROL 2024;96:110-120.

TRIP6 promotes neural stem cell maintenance through YAP-mediated Sonic Hedgehog activation.

In the adult mammalian brain, new neurons are continuously generated from neural stem cells (NSCs) in the subventricular zone (SVZ)-olfactory bulb (OB) pathway. YAP, a transcriptional co-activator of the Hippo pathway, promotes cell proliferation and inhibits differentiation in embryonic neural progenitors. However, the role of YAP in postnatal NSCs remains unclear. Here, we showed that YAP was present in NSCs of the postnatal mouse SVZ. Forced expression of Yap promoted NSC maintenance and inhibited differentiation, whereas depletion of Yap by RNA interference or conditional knockout led to the decline of NSC maintenance, premature neuronal differentiation, and collapse of neurogenesis. For the molecular mechanism, thyroid hormone receptor-interacting protein 6 (TRIP6) recruited protein phosphatase PP1A to dephosphorylate LATS1/2, therefore inducing YAP nuclear localization and activation. Moreover, TRIP6 promoted NSC maintenance, cell proliferation, and inhibited differentiation through YAP. In addition, YAP regulated the expression of the Sonic Hedgehog (SHH) pathway effector Gli2 and Gli1/2 mediated the effect of YAP on NSC maintenance. Together, our findings demonstrate a novel TRIP6-YAP-SHH axis, which is critical for regulating postnatal neurogenesis in the SVZ-OB pathway.

E3 ligase adaptor FBXO7 contributes to ubiquitination and proteasomal degradation of SIRT7 and promotes cell death in response to hydrogen peroxide.

Parkinson's disease (PD) is a degenerative disorder of the central nervous system that affects 1% of the population over the age of 60. Although aging is one of the main risk factors for PD, the pathogenic mechanism of this disease remains unclear. Mutations in the F-box-only protein 7 (FBXO7) gene have been previously found to cause early onset autosomal recessive familial PD. FBXO7 is an adaptor protein in the SKP1-Cullin-1-F-box (SCF) E3 ligase complex that facilitates the ubiquitination of substrates. Sirtuin 7 (SIRT7) is an NAD+-dependent histone deacetylase that regulates aging and stress responses. In this study, we identified FBXO7 as a novel E3 ligase for SIRT7 that negatively regulates intracellular SIRT7 levels through SCF-dependent Lys-48-linked polyubiquitination and proteasomal degradation. Consequently, we show that FBXO7 promoted the blockade of SIRT7 deacetylase activity, causing an increase in acetylated histone 3 levels at the Lys-18 and Lys-36 residues and the repression of downstream RPS20 gene transcription. Moreover, we demonstrate that treatment with hydrogen peroxide triggered the FBXO7-mediated degradation of SIRT7, leading to mammalian cell death. In particular, the PD-linked FBXO7-R498X mutant, which reduced SCF-dependent E3 ligase activity, did not affect the stability of SIRT7. Collectively, these findings suggest that FBXO7 negatively regulates SIRT7 stability and may suppress the cytoprotective effects of SIRT7 during hydrogen peroxide-induced mammalian cell death.

Harmonization of CSF and imaging biomarkers in Alzheimer's disease: Need and practical applications for genetics studies and preclinical classification.

In Alzheimer's disease (AD) research, cerebrospinal fluid (CSF) Amyloid beta (Aß), Tau and pTau are the most accepted and well validated biomarkers. Several methods and platforms exist to measure those biomarkers, leading to challenges in combining data across studies. Thus, there is a need to identify methods that harmonize and standardize these values. We used a Z-score based approach to harmonize CSF and amyloid imaging data from multiple cohorts and compared GWAS results using this approach with currently accepted methods. We also used a generalized mixture model to calculate the threshold for biomarker-positivity. Based on our findings, our normalization approach performed as well as meta-analysis and did not lead to any spurious results. In terms of dichotomization, cutoffs calculated with this approach were very similar to those reported previously. These findings show that the Z-score based harmonization approach can be applied to heterogeneous platforms and provides biomarker cut-offs consistent with the classical approaches without requiring any additional data.

Reliability of dynamic causal modelling of resting-state magnetoencephalography.

This study assesses the reliability of resting-state dynamic causal modelling (DCM) of magnetoencephalography (MEG) under conductance-based canonical microcircuit models, in terms of both posterior parameter estimates and model evidence. We use resting-state MEG data from two sessions, acquired 2 weeks apart, from a cohort with high between-subject variance arising from Alzheimer's disease. Our focus is not on the effect of disease, but on the reliability of the methods (as within-subject between-session agreement), which is crucial for future studies of disease progression and drug intervention. To assess the reliability of first-level DCMs, we compare model evidence associated with the covariance among subject-specific free energies (i.e., the 'quality' of the models) with versus without interclass correlations. We then used parametric empirical Bayes (PEB) to investigate the differences between the inferred DCM parameter probability distributions at the between subject level. Specifically, we examined the evidence for or against parameter differences (i) within-subject, within-session, and between-epochs; (ii) within-subject between-session; and (iii) within-site between-subjects, accommodating the conditional dependency among parameter estimates. We show that for data acquired close in time, and under similar circumstances, more than 95% of inferred DCM parameters are unlikely to differ, speaking to mutual predictability over sessions. Using PEB, we show a reciprocal relationship between a conventional definition of 'reliability' and the conditional dependency among inferred model parameters. Our analyses confirm the reliability and reproducibility of the conductance-based DCMs for resting-state neurophysiological data. In this respect, the implicit generative modelling is suitable for interventional and longitudinal studies of neurological and psychiatric disorders.

Deciphering head and neck cancer microenvironment: Single-cell and spatial transcriptomics reveals human papillomavirus-associated differences.

Human papillomavirus (HPV) is a major causative factor of head and neck squamous cell carcinoma (HNSCC), and the incidence of HPV- associated HNSCC is increasing. The role of tumor microenvironment in viral infection and metastasis needs to be explored further. We studied the molecular characteristics of primary tumors (PTs) and lymph node metastatic tumors (LNMTs) by stratifying them based on their HPV status. Eight samples for single-cell RNA profiling and six samples for spatial transcriptomics (ST), composed of matched primary tumors (PT) and lymph node metastases (LNMT), were collected from both HPV- negative (HPV- ) and HPV-positive (HPV+ ) patients. Using the 10x Genomics Visium platform, integrative analyses with single-cell RNA sequencing were performed. Intracellular and intercellular alterations were analyzed, and the findings were confirmed using experimental validation and publicly available data set. The HPV+ tissues were composed of a substantial amount of lymphoid cells regardless of the presence or absence of metastasis, whereas the HPV- tissue exhibited remarkable changes in the number of macrophages and plasma cells, particularly in the LNMT. From both single-cell RNA and ST data set, we discovered a central gene, pyruvate kinase muscle isoform 1/2 (PKM2), which is closely associated with the stemness of cancer stem cell-like populations in LNMT of HPV- tissue. The consistent expression was observed in HPV- HNSCC cell line and the knockdown of PKM2 weakened spheroid formation ability. Furthermore, we found an ectopic lymphoid structure morphology and clinical effects of the structure in ST slide of the HPV+ patients and verified their presence in tumor tissue using immunohistochemistry. Finally, the ephrin-A (EPHA2) pathway was detected as important signals in angiogenesis for HPV- patients from single-cell RNA and ST profiles, and knockdown of EPHA2 declined the cell migration. Our study described the distinct cellular composition and molecular alterations in primary and metastatic sites in HNSCC patients based on their HPV status. These results provide insights into HNSCC biology in the context of HPV infection and its potential clinical implications.

RNA-binding protein-regulated fibronectin is essential for EGFR-activated metastasis of head and neck squamous cell carcinoma.

There is a higher expression level of epidermal growth factor receptor (EGFR) in up to 90% of advanced head and neck squamous cell carcinoma (HNSCC) tissue than in normal surrounding tissues. However, the role of RNA-binding proteins (RBPs) in EGFR-associated metastasis of HNSCC remains unclear. In this study, we reveal that RBPs, specifically nucleolin (NCL) and heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2B1), correlated with the mesenchymal phenotype of HNSCC. The depletion of RBPs significantly attenuated EGF-induced HNSCC metastasis. Intriguingly, the EGF-induced EMT markers, such as fibronectin, were regulated by RBPs through the ERK and NF-κB pathway, followed by the enhancement of mRNA stability of fibronectin through the 5' untranslated region (5'-UTR) of the gene. The upregulation of fibronectin triggered the integrin signaling activation to enhance tumor cells' attachment to endothelial cells and increase endothelial permeability. In addition, the concurrence of EGFR and RBPs or EGFR and fibronectin was associated with overall survival and disease-free survival of HNSCC. The in vivo study showed that depletion of NCL, hnRNPA2B1, and fibronectin significantly inhibited EGF-promoted extravasation of tumor cells into lung tissues. The depletion of fibronectin or treatment with integrin inhibitors dramatically attenuated EGF-induced HNSCC metastatic nodules in the lung. Our data suggest that the RBPs/fibronectin axis is essential for EGF-induced tumor-endothelial cell interactions to enhance HNSCC cell metastasis.

The effect of oxytocin nasal spray on social interaction in young children with autism: a randomized clinical trial.

Early supports to enhance social development in children with autism are widely promoted. While oxytocin has a crucial role in mammalian social development, its potential role as a medication to enhance social development in humans remains unclear. We investigated the efficacy, tolerability, and safety of intranasal oxytocin in young children with autism using a double-blind, randomized, placebo-controlled, clinical trial, following a placebo lead-in phase. A total of 87 children (aged between 3 and 12 years) with autism received 16 International Units (IU) of oxytocin (n = 45) or placebo (n = 42) nasal spray, morning and night (32 IU per day) for twelve weeks, following a 3-week placebo lead-in phase. Overall, there was no effect of oxytocin treatment over time on the caregiver-rated Social Responsiveness Scale (SRS-2) (p = 0.686). However, a significant interaction with age (p = 0.028) showed that for younger children, aged 3-5 years, there was some indication of a treatment effect. Younger children who received oxytocin showed improvement on caregiver-rated social responsiveness ( SRS-2). There was no other evidence of benefit in the sample as a whole, or in the younger age group, on the clinician-rated Clinical Global Improvement Scale (CGI-S), or any secondary measure. Importantly, placebo effects in the lead-in phase were evident and there was support for washout of the placebo response in the randomised phase. Oxytocin was well tolerated, with more adverse side effects reported in the placebo group. This study suggests the need for further clinical trials to test the benefits of oxytocin treatment in younger populations with autism.Trial registration www.anzctr.org.au (ACTRN12617000441314).

A comprehensive study of pre-eclampsia in IVF and natural conceptions: clinical phenotypes, perinatal outcomes and neonatal echocardiography.

RESEARCH QUESTION: What differences exist in the phenotypes of pre-eclampsia, perinatal outcomes and neonatal echocardiography between pregnancies conceived naturally and through IVF? DESIGN: Six hundred and ten women diagnosed with pre-eclampsia between January 2002 and December 2022 were included in this study. This research was conducted within the IVF and Maternal-Fetal Medicine Department of Kaohsiung Chang Gung Memorial Hospital, Taiwan. Participants were divided into two groups: those who achieved pregnancy through IVF, and those who conceived naturally. The phenotypes of pre-eclampsia and perinatal outcomes were assessed using a propensity-matched sample (n = 218), along with neonatal echocardiography. RESULTS: After conducting propensity score matching, the natural conception group had a higher prevalence of early-onset pre-eclampsia (53.9% versus 37.7%, P = 0.04) and exhibited more severe features of pre-eclampsia (89.1% versus 69.8%, P = 0.01) compared with the IVF group. Regarding perinatal outcomes, neonates in the IVF group had higher placental weights compared with the natural conception group (580 versus 480 g, P = 0.031). The prevalence of abnormal findings on neonatal echocardiography was similar between the groups. Multivariate analysis showed that greater gestational age at delivery reduced the likelihood of abnormal findings on echocardiography [adjusted risk ratio (aRR) 0.950, P = 0.001], while pregestational diabetes mellitus increased the likelihood of abnormal findings (aRR 1.451, P = 0.044). Septal defects were the most common type of defect, occurring in 16.1% of infants. CONCLUSION: The impact of IVF conception on the severity of pre-eclampsia is not as expected. Neonatal echocardiography revealed a higher prevalence of abnormalities in offspring of women with pre-eclampsia compared with the general population. However, these issues were not linked to the method of conception, suggesting the existence of undisclosed factors that could influence the clinical features and perinatal outcomes of pre-eclampsia.

Identification of Early Events in Serrated Pathway Colorectal Tumorigenesis by Using Digital Spatial Profiling.

INTRODUCTION: The colorectal serrated pathway involves precursor lesions known as sessile serrated lesions (SSL) and traditional serrated adenomas (TSA). Mutations in BRAF or KRAS are crucial early events in this pathway. Additional genetic and epigenetic changes contribute to the progression of these lesions into high-grade lesions and, eventually, invasive carcinoma. METHODS: We employed digital spatial profiling to investigate the transcriptional changes associated with SSL and TSA. The genes identified are confirmed by immunohistochemical (IHC) staining. Colorectal cancer (CRC) cell lines with CEACAM6 overexpression and knockdown were established to study the roles of CEACAM6 on tumorigenesis of CRC. RESULTS: Ten genes were upregulated in SSL and TSA, and seven were upregulated in both types of lesions. IHC staining confirmed overexpression of CEACAM6, LCN2, KRT19, and lysozyme in SSL and TSA. CEACAM6 expression is an early event in the serrated pathway but a late event in the conventional pathway. Using cell line models, we confirmed that CEACAM6 promotes CRC cells' proliferation, migration, and invasion abilities. CONCLUSION: These results highlight that the transcriptional changes in the early stages of tumorigenesis exhibit relative uniformity. Identifying these early events may hold significant promise in elucidating the mechanisms behind tumor initiation.

A singleton pregnancy with placental chorioangioma and hydrops fetalis complicated with mirror syndrome and ritodrine-induced side effects: a case report.

BACKGROUND: Ritodrine hydrochloride is a widely used beta-adrenergic agonist used to stop preterm labor in Taiwan. Many side effects causing maternal morbidity and mortality have been reported. We report a case complicated with ritodrine-induced side effects and mirror syndrome that was associated with placental chorioangioma. CASE PRESENTATION: A 36-year-old singleton pregnant woman at 25 6/7 weeks of gestation, with an undiagnosed placental chorioangioma, underwent tocolysis due to preterm uterine contractions. Her clinical condition deteriorated, attributed to mirror syndrome and adverse events induced by ritodrine. An emergency cesarean section was performed at 27 1/7 weeks of gestation, delivering an infant with generalized subcutaneous edema. A placental tumor measuring 8.5 cm was discovered during the operation, and pathology confirmed chorioangioma. Gradual improvement in her symptoms and laboratory data was observed during the postpartum period. Identifying mirror syndrome and ritodrine-induced side effects poses challenges. Therefore, this case is educational and warrants discussion. CONCLUSION: Our case demonstrates mirror syndrome induced by chorioangioma, which is rare, and ritodrine-induced side effects. The cessation of intravenous ritodrine and delivery are the best methods to treat maternal critical status due to fluid overload.

Modification of Risk for All-Cause and Cardiovascular Disease-Related Mortality with Changes in the Body Mass Index in Older Individuals: A Population-Based Cohort Study.

INTRODUCTION: Existing evidence evaluating the impact of change in body mass index (BMI) on the risk of all-cause and cardiovascular disease (CVD)-related mortality in older people is limited and inconsistent. This population-based cohort study evaluated the association of changes in BMI over time with all-cause and CVD-related mortality in older adults. METHODS: We recruited 55,351 adults aged over 65 years between 2006 and 2011 from Taipei Elderly Health Examination Program who underwent repeated annual health examinations at 3.2-year intervals and were followed up for mortality over 5.5 years. Cox proportional hazard and Fine-Gray sub-distribution hazard models with death from non-CVD causes as the competing risk were used to determine the impact of changes in BMI status on the risk of all-cause or CVD-related mortality, respectively. RESULTS: Over 227,967 person-years of follow-up, 4,054 participants died, including 940 (23.2%) CVD-related deaths. After adjusting for other covariates, >10% decrease in BMI was significantly associated with a higher risk of all-cause (adjusted hazard ratio [AHR] = 1.93; 95% confidence interval [CI]: 1.74-2.13) and CVD-related mortality (AHR = 1.96; 95% CI: 1.60-2.40), compared with stable BMI. Sensitivity analysis showed that a >10% decrease in BMI was significantly associated with a high risk of all-cause and CVD-related mortality in participants with normal weight, underweight, overweight, or obesity at baseline. CONCLUSION: Older adults with >10% decrease in BMI are at high risk of all-cause and CVD-related mortality. Our findings suggest that older individuals experiencing a substantial reduction in BMI should undergo a thorough evaluation to minimize the risks associated with mortality.

Protective Effects of an Oligo-Fucoidan-Based Formula against Osteoarthritis Development via iNOS and COX-2 Suppression following Monosodium Iodoacetate Injection.

Osteoarthritis (OA) is a debilitating joint disorder characterized by cartilage degradation and chronic inflammation, accompanied by high oxidative stress. In this study, we utilized the monosodium iodoacetate (MIA)-induced OA model to investigate the efficacy of oligo-fucoidan-based formula (FF) intervention in mitigating OA progression. Through its capacity to alleviate joint bearing function and inflammation, improvements in cartilage integrity following oligo-fucoidan-based formula intervention were observed, highlighting its protective effects against cartilage degeneration and structural damage. Furthermore, the oligo-fucoidan-based formula modulated the p38 signaling pathway, along with downregulating cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression, contributing to its beneficial effects. Our study provides valuable insights into targeted interventions for OA management and calls for further clinical investigations to validate these preclinical findings and to explore the translational potential of an oligo-fucoidan-based formula in human OA patients.

Contrast-enhanced ultrasound features as a potential biomarker for the prediction of breast cancer recurrence.

PURPOSE: To investigate the associations between contrast-enhanced ultrasound imaging features and disease recurrence among patients with locally advanced breast cancer treated with neoadjuvant chemotherapy. MATERIALS AND METHODS: In the study, pre- and post-neoadjuvant chemotherapy contrast-enhanced ultrasound images of 43 patients with breast cancer were retrospectively analysed. Post-acquisition image processing involved the placement of freehand-drawn regions of interest, followed by the generation of blood flow kinetics representing blood volume and velocity for these regions of interest. Qualitative and quantitative contrast-enhanced ultrasound parameters were compared to predict recurrence, and receiver operating characteristic analysis was used to evaluate predictive ability. RESULTS: Among the 43 patients, 10 (23%) exhibited disease recurrence (median [range]: 27 [4-68] months). Post-neoadjuvant chemotherapy peak enhancement, wash-in area under the curve, wash-out area under the curve, and wash-in and wash-out area under the curve (p=0.003, p=0.004, p=0.026, and p=0.014, respectively) differed between the no-recurrence and recurrence groups. The area under the receiver operating characteristic curve (0.88; 95% confidence interval: 0.75-1.00) for post-neoadjuvant chemotherapy peak enhancement was the highest among the contrast-enhanced ultrasound parameters, with a cut-off of 13.33 arbitrary units. CONCLUSION: Higher peak enhancement on post-neoadjuvant chemotherapy contrast-enhanced ultrasound images was associated with recurrence in women with locally advanced breast cancer and is a potential biomarker of tumor recurrence.

Label-Free Three-Dimensional Morphological Characterization of Cell Death Using Holographic Tomography.

This study presents a novel label-free approach for characterizing cell death states, eliminating the need for complex molecular labeling that may yield artificial or ambiguous results due to technical limitations in microscope resolution. The proposed holographic tomography technique offers a label-free avenue for capturing precise three-dimensional (3D) refractive index morphologies of cells and directly analyzing cellular parameters like area, height, volume, and nucleus/cytoplasm ratio within the 3D cellular model. We showcase holographic tomography results illustrating various cell death types and elucidate distinctive refractive index correlations with specific cell morphologies complemented by biochemical assays to verify cell death states. These findings hold promise for advancing in situ single cell state identification and diagnosis applications.

Alzheimer's polygenic risk scores are associated with cognitive phenotypes in Down syndrome.

INTRODUCTION: This study aimed to investigate the influence of the overall Alzheimer's disease (AD) genetic architecture on Down syndrome (DS) status, cognitive measures, and cerebrospinal fluid (CSF) biomarkers. METHODS: AD polygenic risk scores (PRS) were tested for association with DS-related traits. RESULTS: The AD risk PRS was associated with disease status in several cohorts of sporadic late- and early-onset and familial late-onset AD, but not in familial early-onset AD or DS. On the other hand, lower DS Mental Status Examination memory scores were associated with higher PRS, independent of intellectual disability and APOE (PRS including APOE, PRSAPOE , p = 2.84 × 10-4 ; PRS excluding APOE, PRSnonAPOE , p = 1.60 × 10-2 ). PRSAPOE exhibited significant associations with Aß42, tTau, pTau, and Aß42/40 ratio in DS. DISCUSSION: These data indicate that the AD genetic architecture influences cognitive and CSF phenotypes in DS adults, supporting common pathways that influence memory decline in both traits. HIGHLIGHTS: Examination of the polygenic risk of AD in DS presented here is the first of its kind. AD PRS influences memory aspects in DS individuals, independently of APOE genotype. These results point to an overlap between the genes and pathways that leads to AD and those that influence dementia and memory decline in the DS population. APOE ε4 is linked to DS cognitive decline, expanding cognitive insights in adults.

Post-GWAS multiomic functional investigation of the TNIP1 locus in Alzheimer's disease highlights a potential role for GPX3.

INTRODUCTION: Recent genome-wide association studies (GWAS) have reported a genetic association with Alzheimer's disease (AD) at the TNIP1/GPX3 locus, but the mechanism is unclear. METHODS: We used cerebrospinal fluid (CSF) proteomics data to test (n = 137) and replicate (n = 446) the association of glutathione peroxidase 3 (GPX3) with CSF biomarkers (including amyloid and tau) and the GWAS-implicated variants (rs34294852 and rs871269). RESULTS: CSF GPX3 levels decreased with amyloid and tau positivity (analysis of variance P = 1.5 × 10-5) and higher CSF phosphorylated tau (p-tau) levels (P = 9.28 × 10-7). The rs34294852 minor allele was associated with decreased GPX3 (P = 0.041). The replication cohort found associations of GPX3 with amyloid and tau positivity (P = 2.56 × 10-6) and CSF p-tau levels (P = 4.38 × 10-9). DISCUSSION: These results suggest variants in the TNIP1 locus may affect the oxidative stress response in AD via altered GPX3 levels. HIGHLIGHTS: Cerebrospinal fluid (CSF) glutathione peroxidase 3 (GPX3) levels decreased with amyloid and tau positivity and higher CSF phosphorylated tau. The minor allele of rs34294852 was associated with lower CSF GPX3. levels when also controlling for amyloid and tau category. GPX3 transcript levels in the prefrontal cortex were lower in Alzheimer's disease than controls. rs34294852 is an expression quantitative trait locus for GPX3 in blood, neutrophils, and microglia.