45 Senolytic Therapy Transiently Reduces Inflammatory Markers in Primary Blood Mononuclear Cells of Individuals with Early Alzheimer’s Disease: Exploring the Conserved Transcriptional Response to Adversity as a Biomarker for Disease State

OBJECTIVES/GOALS: Determine if the Conserved Transcriptional Response to Adversity transcriptomic profile established in primary blood mononuclear cells (PBMC) of chronically stress caregivers, is present in individuals with early Alzheimer’s disease. Chronic stress is a risk factor for Alzheimer’s, and may be an untapped biomarker for disease risk and pathology. METHODS/STUDY POPULATION: To collect preliminary data on the Conserved Transcriptional Response to Adversity profile in individuals with Alzheimer’s disease, we were able to utilize primary blood mononuclear cell samples from a small open label pilot study called Senolytic Therapy to Modulate the Progression of Alzheimer’s Disease, designed to clear stressed senescent cells. We hypothesized senolytics may beneficially reverse this stress profile. We developed a NanoString assay (measuring 19 inflammatory, 31 type-1 interferon, and 3 antibody synthesis genes) to compare these transcriptomic changes within 4 individuals measured at baseline, post-treatment with an intermittent 12-week senolytic therapy, and at an optional extended post-treatment follow-up time point \u3e 3 months after their post treatment visit. RESULTS/ANTICIPATED RESULTS: There was relative downregulation of expression in transcription in 7 of 19 measured inflammatory genes (FOS, PTGS2, IL8, FOS, Il1b, JUNB, and JUN) in Alzheimer’s disease participants after receiving senolytic treatment (baseline vs. post-treatment). This is consistent with a decrease in the inflammatory arm of the Conserved Transcriptional Response to Adversity profile. These differences were not significant between baseline and the extended follow-up, indicative of a transient effect of senolytic. There were no changes in type 1 interferon or antibody synthesis genes. This data provides preliminary evidence for larger controlled studies to further establish this profile in Alzheimer’s disease, providing exciting evidence for transcript changes that may be reproducible with senolytic therapy. DISCUSSION/SIGNIFICANCE: Literature relevant to Alzheimer’s disease indicates global increases in inflammation paired with deficits in immune response, capturing some genes associated with the Conserved Transcriptional Response to Adversity. This profile may be a useful biomarker for prediction of disease severity or risk of dementia due to chronic stress

Exploration of the tumorigenic, metabolic, and cognitive consequences of tau protein removal

Background: Tau accumulation causes tauopathies and drives cellular senescence, which can lead to inflammation, neurodegeneration, and cognitive impairment. The association between intracellular tau deposition and pathogenesis has prompted therapeutic strategies that reduce tau expression. However, tau is also critical in microtubule stabilization, synaptic plasticity, and maintaining DNA integrity. We investigated the impact of tau removal on brain cell senescence and associated neurocognitive behaviors in aged tau knockout (Mapt0/0) and wild type control (Mapt+/+) mice. We also assessed physical, metabolic, histological, and biochemical outcomes in Mapt0/0 and Mapt+/+ mice and in response to high fat diet (HFD), a stressor that drives DNA damage. Method: 20-month-old female Mapt0/0 and Mapt+/+ mice were subjected to the Elevated Plus Maze to assess anxiety-like behavior. Mice were then fed control (CTL) or HFD (60% kcal fat) for 9 weeks. Behavioral and physical measures were then assessed, and brain tissue was further analyzed via gene expression, biochemistry, and histological assays. Result: Tau knockout and HFD, separately and additively, caused weight gain and insulin resistance. Removing tau primed cells to proliferate, as Mapt0/0 mice had increased body size, organ size, and tumor burden compared to Mapt+/+. We observed no difference in senescence between genotypes on CTL diet. The HFD increased senescence only in Mapt+/+ mice, whereas Mapt0/0 mice displayed increased tumor burden. Mapt0/0 mice displayed anxiety- and depressive-like behaviors on both diets. Transcriptomic and protein expression data revealed that several molecules responded similarly to tau removal and HFD exposure, but Mapt+/+ and Mapt0/0 mice responded differently to HFD. Genotype differences in DNA damage and cell cycle dysregulation were also observed. Conclusion: Mapt0/0 mice did not accumulate senescent cells but demonstrated anxiety-like behaviors in the presence of elevated DNA damage; thus tau knockout may drive neuropsychiatric phenotypes which can be dissociated from obesity and senescence. Mapt0/0 mice also developed tumors, suggesting that tau plays a critical role in cell fate decisions, including senescence versus cancer. Overall, we found that tau removal prevents senescent cell accumulation with the tradeoff of tumorigenic, metabolic, and cognitive consequences. We caution against removing tau until a better understanding of its physiological roles are defined

Preliminary neurocognitive finding from a multi-site study investing long-term neurological impact of COVID-19 using ultra-high field 7 Tesla MRI-based neuroimaging

Background: Globally, over six hundred million cases of SARS-CoV-2 have been confirmed. As the number of individuals in recovery rises, examining long-term neurological effects, including cognitive impairment and cerebral microstructural and microvascular changes, has become paramount., We present preliminary cognitive findings from an ongoing multi-site study investigating the long-term neurological impacts of COVID-19 using 7 Tesla MRI-based neuroimaging. Methods: Across 3 US and 1 UK sites, we identified adult (\u3e=18) COVID-19 survivors (CS) and healthy controls (HC) without significant pre-existing medical, neurological, or psychiatric illness. Using the National Alzheimer’s Coordinating Center (NACC) Uniform Data Set (UDS-3) battery and Norms Calculator, 12 cognitive scores were adjusted for age, sex, and education and classified as either unimpaired or mild (\u3c9th percentile), moderate (\u3c2nd percentile), or severely impaired (\u3c1st percentile). The observed frequency of impairment across the two groups is reported along with proportional differences (PD) and confidence intervals (CI). Illness severity and time since infection were evaluated as potential associates of cognitive impairment. Results: Over a period of 11 months, we enrolled 108 participants. At the time of reporting, 80 (46.3% female; mean age: 60.3 ± 8.6; 61 CS, 19 HC) had completed cognitive assessments. Of the participants for whom we ascertained time since symptom onset and illness severity (n=51 and 43, respectively), 31.4% had their index COVID-19 infection within the past year, and 60.5% had a severe to critical infection (Table 1). Table 2 reports observed frequency of impairment for each metric. Aggregating all 12 cognitive metrics, we found 45 (73.8%) of CS had at least one impairment [vs HC: 10 (52.6%)]. A significantly greater proportion of CS had at least one moderate to severe or severe impairment (Figure 1). CS also had significantly higher frequencies of presenting with two or more mild to severe impairments [PD 0.33 (0.13, 0.54)]. Illness severity and time since infection were not significantly associated with cognitive impairment. Conclusion: Our preliminary results are consistent with potentially sustained COVID-associated cognitive impairment in a subset of participants. Enrollment in the multi-site cohort is ongoing, and updated results will be presented along with ultra-high field MRI-based neuroimaging correlates

Hippocampal subfield volumes in COVID-19: a preliminary multicenter study using 7T MRI

Background: Hippocampal formation atrophy is a well-established imaging biomarker of several neurological diseases, including Alzheimer\u27s disease, temporal lobe epilepsy, and schizophrenia. The hippocampus is divided into subfields that have different functions and vary in sensitivity to different diseases. This study investigates the potential interaction between COVID-19 and the various hippocampus subfields, which may shed light on the long-term neurological consequences of the virus. Method: We obtained high-resolution T1-weighted (T1w) and T2-weighted (T2w) MRI images using 7T scanners located at three sites in two countries: Pittsburgh (n=14) and Texas (San Antonio and Houston) (n=40) in the USA, and Nottingham, UK (n=33). We evaluated the hippocampus subfields using the ASHS package [1-3]. Imaging sets of 51 subjects with minimal or no manual segmentation corrections (Figures 1 and 2) were included in the analysis. We conducted T-tests with Bonferroni correction, adjusting for age and intracranial volume to identify the differences in hippocampus subfield volumes across groups. Result: Participants who needed admission into the ICU due to Covid-19 showed a significantly lower (p-value=0.0034) left CA1 volume compared to participants who did not require ICU (Figure 3). In addition, several other non-significant trends were observed. Conclusion: Our preliminary findings suggest that Covid-19 may impact the hippocampus, particularly in patients who required intensive care. However, the study - as of to date - has a small sample size and lacks a comparison group with patients who were admitted into ICU for acute illnesses other than Covid-19. Additionally, longitudinal data is needed to track the long-term effects of the disease on the hippocampal subfields

Lower locus coeruleus integrity in older COVID-19 survivors: initial findings from an international 7T MRI consortium

Background: The SARS-CoV-2 coronavirus has been associated with structural brain changes, consistent with its neurological manifestations. Recent studies showed a specific predilection for brainstem glial activation and hypometabolism, possibly indicating involvement of the locus coeruleus. The locus coeruleus (LC) modulates many cognitive functions and behaviors and its norepinephrine projections regulate both immune responses and vascular reactivity. We aimed to examine differences in LC integrity between COVID-19 survivors and controls. Method: Participants are enrolled across 3 US and 1 UK sites using harmonized cognitive and 7T MR-imaging protocols. Here, we analyzed data from 18 participants enrolled at Houston Methodist (12 COVID-19 survivors, 6 controls; Figure 1). COVID-19 survivors were required to have had a positive antigen test and an illness syndrome consistent with COVID-19. Healthy controls were required to have no significant pre-existing medical, neurologic, or psychiatric illness and no illness requiring hospitalization in the last 2 years. LC imaging was performed using a dedicated 7T MT-TFL sequence (0.4 x 0.4 x0.5mm). A site-specific normalized template was constructed using ANTs/FSL. The entire average LC integrity as well as voxel-wise integrity values were compared between COVID-19 survivors and controls using a robust linear regression (age-controlled and threshold free cluster enhancement corrected). LC integrity was correlated with age, sex, ethnicity and cognition using Spearman’s rank correlation. Result: Average LC integrity was not correlated with age, sex, or Hispanic ethnicity (p\u3e0.3). COVID-19 survivors did not differ from Controls when examining the entire LC (p=0.54). Voxel-wise analyses revealed a small cluster (19 voxels) in the middle portion of the left LC where COVID-19 survivors exhibited lower LC integrity than controls (p=0.005; Figure 2). Integrity of this cluster was not related to age or Hispanic ethnicity (p=0.9). LC integrity did not correlate with cognitive performance within the COVID-19 survivors (Trail Making Test B: p=0.43; Craft Story delayed recall p=0.47; MoCA p=0.84). Conclusion: Consistent with previous animal and human studies, our initial findings provide evidence for neuroinvasive potential of SARS-CoV-2 localized in the middle LC. In the future, we aim to expand our sample and link these observations to the neurocognitive sequelae of COVID-19

Associations between neuropsychiatric symptoms and ADRD serum biomarkers in Mexican American and non-Hispanic white adults with mild cognitive impairment

Background: Mild cognitive impairment (MCI) is a heterogenous diagnostic category with trajectories ranging from reversion to unimpaired cognition to progression to dementia. Neuropsychiatric symptoms such as depression and irritability are common and influence quality of life of patients and caregivers. The role of neuropsychiatric symptoms on disease biology, presentation, and course remains poorly understood. The goal of this study was to evaluate the associations between neuropsychiatric symptoms and serum ADRD biomarkers in Mexican American and non-Hispanic white participants diagnosed with MCI. Method: Participants from the Texas Alzheimer’s Research and Care Consortium underwent a blood draw and clinical evaluation, including psychopathological and cognitive assessments. Diagnoses of MCI were adjudicated in consensus reviews. The presence and severity of neuropsychiatric symptoms were assessed by informant report using the Neuropsychiatric Inventory (NPI). Serum levels of total tau, neurofilament light (NfL), and glial fibrillary acidic protein (GFAP) were assessed using Simoa HD-X Analyzer. Associations between NPI total score and individual items with serum biomarker levels were assessed using linear regression adjusted for age and sex. Result: A total of 425 participants (mean age: 71 ± 9 years, 62% female, 74% Mexican American) had a diagnosis of MCI and serum ADRD biomarkers (Table 1). Total NPI score was not associated with total tau (ß=0.002, p=0.609), NfL (ß=0.001, p=0.658), or GFAP (ß=0.001, p=0.777). However, endorsement of appetite changes was associated with higher NfL (ß=0.077, p=0.006) and GFAP (ß=0.088, p=0.002) levels. Stratified analyses indicated associations of appetite changes with serum NfL (ß=0.108, p=0.002) and GFAP (ß=0.095, p=0.003) in Mexican Americans, but not in non-Hispanic whites (NfL: ß=0.022, p=0.633, GFAP: ß=0.102, p=0.066).There were no other significant associations between individual items on the NPI with serum biomarkers (p\u3e0.05, Bonferroni adjustment p±0.003). Conclusion: Within Mexican American adults with MCI, changes in appetite were associated with higher serum NFL and GFAP levels. As elevations in circulating NfL and GFAP levels are associated with ADRD pathology and accelerated disease progression, appetite changes, a non-invasive and easily discernible behavioral phenotype, may predict higher likelihood of worsening cognitive course. Future longitudinal studies will be necessary to confirm predictive utility of appetite changes for disease progression

Covid-19 may have a detrimental impact on sensorimotor function

Background: The long-term impact of COVID-19 on global health is still unknown. Sensorimotor biomarkers may be promising indicators of lasting effects of COVID-19. Although normal aging may cause changes in sensorimotor function, more severe changes may indicate the subsequent impacts of COVID-19 on brain health. The objective of this study was to investigate the association between COVID-19 and sensorimotor markers (grip strength, gait, and smell) in the 7T neuroCOVID consortium, which is comprised of 5 sites: The University of Texas Health Science Center at San Antonio, Houston Methodist Research Institute, The University of Pittsburgh, Massachusetts General Hospital, and Nottingham University (UK). Methods: We studied 101 adult participants (mean age 60.9 ± 8.5 years, range 45-80 years, 51% women) without prior cognitive impairment or cerebrovascular disease from the 7T consortium across 3 US and 1 UK sites. The sample included 77 COVID-19 survivors and 24 healthy controls. Sensorimotor markers were measured for olfaction (n=59; 12-item Brief Smell Identification Test (B-SIT)), grip strength (n=97; measured using a hand dynamometer), and Gait (n=101; 4-meter normal walk time and n=99; 4-meter fast-paced walk time). To assess the association between COVID-19 and sensorimotor outcomes, we performed a series of linear regression models adjusting for age, sex, site, and handedness (grip strength only). Statistical significance was set at a 5% level. Results: As compared to healthy controls, COVID-19 survivors, on average had a significantly reduced hand grip in the right hand (β ± standard error: -0.18 ± 0.07, p=0.006). We also observed associations with reduced gait speed. COVID-19 survivors, on average, had a slower walk time in both normal (0.17 ± 0.06, p=0.004) and fast-paced (0.04 ± 0.02, p=0.022) as compared to healthy controls. We did not observe any statistical associations between COVID-19 survivors and left-hand grip strength or B-SIT. Conclusions: These results highlight that Covid-19 infection may have a detrimental impact on sensorimotor function. Additional analysis with a larger sample size are ongoing, which will allow us to further assess the effect of infection severity. Future studies will look to evaluate the association between sensorimotor markers, cognition, and ultra-high field 7T MRI-based imaging markers

Investigating white matter hyperintensities in a multicenter COVID-19 study using 7T MRI

Background: Emerging evidence indicates that COVID-19 can negatively impact patient’s brain health (Douaud et al., 2022) (Cecchetti et al., 2022). Common clinical symptoms include brain fog, headaches, difficulty concentrating, and loss of sense of smell or taste. Some studies suggest that SARS-CoV-2 infection can damage the blood brain barrier either directly or through immune-inflammatory mechanisms (Zhang, et al. 2021). White matter hyperintensities (WMH) are imaging biomarkers of brain vascular or inflammatory injury. We investigated the association between severity of COVID-19 infection and burden of white matter hyperintensity volumes within a diverse multi-nation, multi-racial cohort using 7 Tesla (7T) MRI that can detect more subtle injury than conventional 1.5 or 3T MRI. Method: Participants were recruited at 4 sites: Pittsburgh, San Antonio and Houston, USA, and Nottingham, UK. To date, we have scanned and included the following participants in our analysis (Table 1). Detailed cognitive, neurological, mood and functional assessments and high-resolution MRI scans were collected. Subsequent WMH segmentation was performed using our in-house built deep learning based model (Figure 1). All segmentations were visually inspected and manually corrected before statistical analysis. Normalized WMH is calculated as a ratio of the WMH volume and the intracranial volume (WMH/ICV). Imaging data for an additional 36 age-matched controls were retrieved from the 7 Tesla Bioengineering Research Program (7TBRP) imaging bank at Pittsburgh. Result: Figure 1 shows the WMH segmentation outputs from our deep learning based model on images acquired at the 3 sites. Our Linear regression models along with our non-parametric Kruskal-Wallis test result suggests that compared to mild COVID cases and healthy control, COVID infected individuals that were ICU admitted show elevated WMH burden (Figure 2). Conclusion: Our results demonstrate that white matter hyperintensity volumes were higher among patients who had severe acute COVID infection that required ICU admission, compared to healthy age-matched controls. In contrast, no difference in white matter burden was observed in patients with mild COVID infection compared to healthy controls. Additional data (both cross-sectional and longitudinal), including more sensitive MRI measures is being collected to define the full spectrum of brain injury associated with sequelae of COVID infection

Evaluation of Exploratory Fluid Biomarker Results from a Phase 1 Senolytic Trial in Mild Alzheimer\u27s Disease

Senescent cell accumulation contributes to the progression of age-related disorders including Alzheimer\u27s disease (AD). Clinical trials evaluating senolytics, drugs that clear senescent cells, are underway, but lack standardized outcome measures. Our team recently published data from the first open-label trial to evaluate senolytics (dasatinib plus quercetin) in AD. After 12-weeks of intermittent treatment, we reported brain exposure to dasatinib, favorable safety and tolerability, and modest post-treatment changes in cerebrospinal fluid (CSF) inflammatory and AD biomarkers using commercially available assays. Herein, we present more comprehensive exploratory analyses of senolytic associated changes in AD relevant proteins, metabolites, lipids, and transcripts measured across blood, CSF, and urine. These analyses included mass spectrometry for precise quantification of amyloid beta (Aß) and tau in CSF; immunoassays to assess senescence associated secretory factors in plasma, CSF, and urine; mass spectrometry analysis of urinary metabolites and lipids in blood and CSF; and transcriptomic analyses relevant to chronic stress measured in peripheral blood cells. Levels of Aß and tau species remained stable. Targeted cytokine and chemokine analyses revealed treatment-associated increases in inflammatory plasma fractalkine and MMP-7 and CSF IL-6. Urinary metabolites remained unchanged. Modest treatment-associated lipid profile changes suggestive of decreased inflammation were observed both peripherally and centrally. Blood transcriptomic analysis indicated downregulation of inflammatory genes including FOS, FOSB, IL1β, IL8, JUN, JUNB, PTGS2. These data provide a foundation for developing standardized outcome measures across senolytic studies and indicate distinct biofluid-specific signatures that will require validation in future studies. ClinicalTrials.gov: NCT04063124

Perforated peptic ulcer (PPU) treatment: an Italian nationwide propensity score-matched cohort study investigating laparoscopic vs open approach

BackgroundPerforated peptic ulcer (PPU) remain a surgical emergency accounting for 37% of all peptic ulcer-related deaths. Surgery remains the standard of care. The benefits of laparoscopic approach have been well-established even in the elderly. However, because of inconsistent results with specific regard to some technical aspects of such technique surgeons questioned the adoption of laparoscopic approach. This leads to choose the type of approach based on personal experience. The aim of our study was to critically appraise the use of the laparoscopic approach in PPU treatment comparing it with open procedure.MethodsA retrospective study with propensity score matching analysis of patients underwent surgical procedure for PPU was performed. Patients undergoing PPU repair were divided into: Laparoscopic approach (LapA) and Open approach (OpenA) groups and clinical-pathological features of patients in the both groups were compared.ResultsA total of 453 patients underwent PPU simple repair. Among these, a LapA was adopted in 49% (222/453 patients). After propensity score matching, 172 patients were included in each group (the LapA and the OpenA). Analysis demonstrated increased operative times in the OpenA [OpenA: 96.4 +/- 37.2 vs LapA 88.47 +/- 33 min, p = 0.035], with shorter overall length of stay in the LapA group [OpenA 13 +/- 12 vs LapA 10.3 +/- 11.4 days p = 0.038]. There was no statistically significant difference in mortality [OpenA 26 (15.1%) vs LapA 18 (10.5%), p = 0.258]. Focusing on morbidity, the overall rate of 30-day postoperative morbidity was significantly lower in the LapA group [OpenA 67 patients (39.0%) vs LapA 37 patients (21.5%) p = 0.002]. When stratified using the Clavien-Dindo classification, the severity of postoperative complications was statistically different only for C-D 1-2.ConclusionsBased on the present study, we can support that laparoscopic suturing of perforated peptic ulcers, apart from being a safe technique, could provide significant advantages in terms of postoperative complications and hospital stay