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Batalha, C. M. P. F.

Publications and source records attributed to Batalha, C. M. P. F..

4 recordsLinked to original sources

Characterizing Post-Mortem Brain Molecular Taxonomy of Cognitive Resilience and Translating it to Living Humans

Here, we define cognitive resilience as slower or faster cognitive decline after we regress out the effects of common brain neuropathologies. Its understanding could provide important insights into the biology underlying cognitive health, enabling the development of more effective strategies to prevent cognitive decline and dementia. However, this requires the development of a practical method to quantify resilience and measure it in living individuals, as well as identifying heterogenous pathways associated with resilience in different individuals. Here, we approach this problem by using a data-driven framework to quantify and characterize molecular signatures underlying cognitive resilience. Using multimodal contrastive trajectory inference (mcTI) on bulk RNA sequencing and tandem mass tag (TMT) proteomic data from 898 post- mortem brain samples from the Religious Orders Study and the Rush Memory and Aging Project (ROSMAP), we derived individual-level molecular pseudotime values reflecting the molecular path from high to low resilience across individuals. Additionally, we identified two distinct molecular subtypes of resilience, each characterized by unique transcriptomic and proteomic signatures, and differing associations with several phenotypes. To translate our brain-derived pseudotime and subtypes to living individuals, we developed prediction models with paired genetics, ante-mortem blood omics, clinical, psychosocial, imaging and device data from the same individuals, demonstrating the potential to predict brain molecular resilience profiles in living persons. Our findings establish a framework for quantifying resilience based on multi- level molecular signatures, identify molecularly distinct resilience subtypes, and demonstrate the feasibility of translating brain-derived molecular profiles to living individuals--laying the groundwork for the development of targeted resilience-promoting interventions in cognitive aging.

neuroscience↗

Brain Multi-Omic Subtypes of Neuroticism Reveal Molecular Signatures linked to Alzheimer's Disease

ImportanceMolecular mechanisms linking neuroticism with Alzheimers disease traits are unknown. ObjectiveTo identify molecular subtypes of neuroticism and examine their association with ADRD traits. DesignThree ongoing cohort studies were used; Religious Orders Study (ROS), Rush Memory and Aging Project (MAP) and Minority Aging Research Study (MARS), that began enrollment in 1994, 1997, and 2004, respectively. SettingOlder priests, nuns, and brothers from across the U.S. (ROS), older adults (MAP) and older African-American adults (MARS) from across the greater Chicago metropolitan area. Participants1,028 decedents with multi-omic data from the dorsolateral prefrontal cortex (DLPFC), the anterior cingulate cortex (AC), and the posterior cingulate gyrus (PCG). Exposure(s)Eight layers of omics (DNA methylation and histone acetylation from DLPFC; RNA seq from AC, DLPFC, and PCG, single-nucleus RNA, TMT proteomics and metabolomics from DLPFC) and Neuroticism using the 12-item version from the NEO Five-Factor Inventory. Main outcome(s) and measure(s)Person-specific multi-omic molecular pseudotime representing molecular progression from low to high phenotypic expression of neuroticism, and three multi-omic brain molecular subtypes of neuroticism which represent distinct omic pathways from no/low neuroticism to high neuroticism that differ by their omic constituents. Participants are exclusively assigned to the subtype which aligns mostly with their multi-omic profile. ResultsThe top drivers of subtype differentiation were transcriptomic alterations across three brain regions (DLPFC, AC, PCG) which extensively and differentially characterized the subtypes. The subtypes were also differentially associated with AD pathology, temporal lobe atrophy, and AD dementia, with subtype N1 showing the strongest associations. Conclusions and RelevanceNeuroticism may be driven by three distinct molecular subtypes, with subtype N1 driving ADRD-related associations, N2 showing some ADRD associations, and N3 being completely independent of these outcomes. Our data provide novel insights into the biology of individual differences in predispositions of neuroticism and its associations with ADRD traits. Key pointsO_ST_ABSQuestionC_ST_ABSWhat are the brain multi-omics molecular signatures linking neuroticism with Alzheimers diseases and related dementias (AD/ADRDs)? FindingsWe identified three distinct brain multi-omic molecular subtypes reflecting different molecular pathways underlying neuroticism. Top omic features of the subtypes were extensively and differentially characterized by transcriptomic alterations across three brain regions - dorsolateral prefrontal cortex, anterior cingulate cortex, and posterior cingulate gyrus. Subtype N1 was strongly associated with AD pathology, AD dementia, and temporal lobe atrophy. MeaningThe association we typically observe between phenotypic neuroticism and ADRD clinical traits might be largely driven by a molecular pathway underlying this trait.

neuroscience↗

Combination of differential expression and co-expression network analyses identify novel conserved age-associated changes among different tissues

Transcriptomic changes occur with age, but the extent of their similarities across tissues is not clear. Previous studies have identified no similarity in age-modulated genes in different tissues. In this study, we sought to identify transcriptional changes with age across tissues using differential network analysis, with the premise that differential expression analysis alone is not capable of detecting all the changes in the transcriptional landscape that occur in tissues with age. Our results show major transcriptional alterations not detected by differential expression analysis that can be detected by differential connectivity analysis. Combining these two analyses, we detected genes changing across tissues, enriched in "RNA splicing" and "RNA processing", and highly connected in protein-protein interaction networks. Co-expression module analyses demonstrated that other genes with tissue-specific variations with age are enriched in pathways that combat accumulation of aberrant RNAs and proteins, which are caused by defective splicing. Additionally, tissues displayed a major reorganization of their genes connectivities with age, with most demonstrating convergent connectivity patterns. Our analyses identify genes and processes which transcriptional changes are conserved across tissues, demonstrating a central role for RNA splicing and processing genes and highlighting the importance of differential network analysis for understanding the ageing transcriptome.

bioinformatics↗

Expression of DNA repair genes is modulated during differentiation of olfactory sensory neurons

Olfactory dysfunction is considered a biomarker of several pathological conditions, including age-associated neurodegenerations, glioblastoma and COVID-19. Olfactory sensory neurons (OSNs) are specialized neurons that detect odorants and send olfactory information to the brain through the olfactory bulb. To perform their function, they are in direct contact with the environment, where they are exposed to several environmental toxins such as atmospheric levels of O2 and volatile molecules. Nonetheless, very little is known about DNA damage levels and expression of DNA repair pathways in these cells. Here we measured nuclear and mitochondrial DNA damage in olfactory epithelium (OE) and compared with levels detected in olfactory bulb (OB) and temporal cortex (TC), as a non-olfactory related central nervous system region. Surprisingly, DNA damage was lower in OE and OB when compared with TC, both for nuclear and mitochondrial genomes. Accordingly, expression of representative genes for all excision repair pathways was detected in OSNs. Moreover, expression of most evaluated DNA repair genes was lower in mature versus OSN progenitors, suggesting that DNA repair is downregulated during differentiation. Analysis of single cell expression data confirmed that expression of the most differentially expressed DNA repair genes decreased from progenitor to mature OSNs. Finally, in situ hybridization data showed that APE1 mRNA levels are lower in the mature OSNs layer of the olfactory epithelium, closest to the nasal cavity lumen. Altogether, we show here that DNA repair pathways are relevant in protecting OSNs against DNA damage accumulation and that differentiation through the OE is accompanied by changes in the expression levels of DNA repair genes.

neuroscience↗