bioRxiv Science⌕ Search

Biology subjects

Mecawi, A. d. S.

Publications and source records attributed to Mecawi, A. d. S..

2 recordsLinked to original sources

Integrative Single-Cell Analysis of Autism Spectrum Disorder Animal Models Reveal Convergent Transcriptomic Dysregulation Involved in Excitatory-Inhibitory Imbalance and Glial Disfunction

Autism Spectrum Disorder (ASD) presents profound clinical and etiological heterogeneity, complicating the identification of core pathophysiological mechanisms. Single-cell RNA sequencing (scRNA-seq) offers cellular resolution but integrating findings across diverse studies remains challenging. Here, we constructed a unified single-cell reference framework by integrating scRNA-seq data from 11 distinct genetic and environmental ASD animal models, encompassing over 300.000 cells across various brain regions and developmental stages. Comparative analyses revealed convergent differentially expressed genes (DEGs) across neuronal and glial populations. Cross-model comparisons validated the integration, showing significant concordance between the unified dataset and individual studies, particularly for neuronal populations, and demonstrating how environmental models like valproic acid exposure recapitulate some of the transcriptomic alterations seen in genetic models. Cell communication analyses support widespread excitatory-inhibitory imbalance and with predicted signaling involving ligands like Pdgfa and Reln. Furthermore, we identified significant glial dysfunction, notably downregulation of crucial functional genes in astrocytes and signatures of metabolic dysregulation in mature oligodendrocytes. Cross-referencing with the SFARI database confirmed significant overlap with high-confidence ASD risk genes, with notable dysregulated in specific cell types included Ermn (upregulated in multiple glia), Foxg1 (downregulated in L5/6 NP neurons) and Mef2c (downregulated in MEIS2-like interneurons). Comparison with human scRNA-seq postmortem data revealed conserved dysregulation, highlighting enrichment of presynaptic/postsynaptic translation processes in neurons (implicating CACNAIA, GRIN2B, CAMK2A, ribosomal proteins) along with enrichment for neurodevelopmental disorder pathways in mature oligodendrocytes, involving NRXN and DLGAP gene networks. This integrative study provides unprecedented insight into the convergent cellular and molecular pathologies underlying ASD, establishing a valuable resource for understanding shared mechanisms and identifying new potential therapeutic targets.

neuroscience↗

The impact of testosterone on paraventricular nucleus gene expression in male and female spontaneously hypertensive rats

BackgroundHypertension is a polygenic, complex disease that impacts men and women differently; whilst the incidence of high blood pressure (BP) is roughly equal over a lifetime, men typically are at higher risk of developing the disease earlier in life, before 50 years of age. There is adequate evidence that the brain is critical for the BP setpoint. The paraventricular nucleus (PVN) of the hypothalamus is an integrative structure that can influence not only neurohumoral responses to blood pressure changes, but also sympathetic drive. Here we manipulate the androgenic status of both male and female spontaneously hypertensive rats (SHRs) to determine how this changes gene expression within the PVN of these animals. MethodsSHR (8-weeks old) were either sham-operated or orchiectomized, whereas all females were oophorectomized, half of which received 10mg testosterone propionate subcutaneously. Mean arterial pressure (MAP) and testosterone (T) were measured by carotid cannulation and ELISA respectively. Sequencing was performed on hand-punched PVN sections and subjected to robust bioinformatic analysis. ResultsIn total, 6,571 differentially regulated genes (DRGs) are regulated in the PVN of male and female rats. High T (endogenous or replaced) correlates with higher MAP in both sexes. Orchidectomy-induced T depletion resulted in the significant regulation of 5,104 genes, involved in thousands of biological roles, including ones related to hormone and sex-hormone signalling. In the female SHR, testosterone replacement in oophorectomized animals induced the regulation of 1,727 genes, sharing many biological functions with those in the high T males. We validated key genes by qPCR to determine false discovery rate. ConclusionsT status in hypertensive rats correlates with MAP, and consistent changes in PVN transcriptome

neuroscience↗