Biology subjects

Yerko, V.

Publications and source records attributed to Yerko, V..

3 recordsLinked to original sources

bioRxiv2025

Characterizing Oligodendrocyte-Lineage Cells and Myelination in the Basolateral Amygdala: Insights from a Novel Methodology in Postmortem Human Brain

The basolateral amygdala (BLA) plays a key role in the pathophysiology of depressive disorders and trauma, yet oligodendrocyte-lineage cells and myelin in this brain region remain understudied in humans. This may be due, at least in part, to the lack of a cost-effective, antibody-based method to isolate oligodendrocytes (OL) and OL precursor cells (OPC) from postmortem brain tissue that is compatible with molecular biology applications. This study aimed to 1) create and validate a method for isolating OPC and OL nuclei from frozen postmortem grey matter; 2) compare OPC and OL gene expression in the BLA between individuals with depression who died by suicide (with or without a history of childhood abuse) and matched controls; and 3) provide histological characterizations of OPC, OL, and myelin in the BLA. Frozen left-hemisphere BLA samples were obtained from brain donors with well-characterized phenotypic information. Immunolabeled nuclei were sorted into OPC (SOX10+/CRYAB-) and OL (SOX10+/CRYAB+) populations, and RNA was measured using a custom Nanostring codeset. Fluorescence in situ hybridization was used to determine OPC (PDGFR+) and OL (MYRF+) densities, and immunofluorescence was used to label axons (NF-H) and myelin (MBP) for myelin area fraction. The method successfully isolated OPC and OL nuclei with correct transcriptomic profiles. In the OL fraction, MOBP was found to be significantly decreased in depressed individuals with a history of child abuse compared to controls, but no other genes showed significant group differences in either fraction. However, significant age-related patterns were observed in both fractions. Furthermore, no significant differences in cell densities or myelin coverage were observed across groups. Lastly, a strong significant correlation between OL density and myelin area fraction was identified. This study provides a novel sorting method and a comprehensive characterization of OL-lineage gene expression, cell densities, and myelin in the human BLA.

neuroscience↗

bioRxiv2024

Pervasive neurovascular dysfunction in the ventromedial prefrontal cortex of female depressed suicides with a history of childhood abuse

Exposure to early life adversity (ELA) poses a significant global public health concern, with profound pathophysiological implications for affected individuals. Studies suggest that ELA contributes to endothelial dysfunction, bringing into question the functional integrity of the neurovascular unit in brain regions vulnerable to chronic stress. Despite the importance of the neurovasculature in maintaining normal brain physiology, human neurovascular cells remain poorly characterized, particularly with regard to their contributory role in ELA-associated pathophysiologies. In this study, we present the first comprehensive transcriptomic analysis of intact microvessels isolated from postmortem ventromedial prefrontal cortex samples from adult healthy controls (CTRL) and matched depressed suicides with histories of ELA. Our findings point to substantive differences between men and women, with the latter exhibiting widespread gene expression changes at the neurovascular unit, including the key vascular nodal regulators KLF2 and KLF4, alongside a broad downregulation of immune-related pathways. These results suggest that the neurovascular unit plays a larger role in the neurobiological consequences of ELA in human females.

neuroscience↗

bioRxiv2023

Universal method for the gentle isolation of intact microvessels from frozen tissue: a multiomic investigation into the neurovasculature

The neurovascular unit (NVU), comprised of endothelial cells, pericytes, smooth muscle cells, astrocytic endfeet and microglia together with neurons, is paramount for the proper function of the central nervous system. The NVU gatekeeps blood-brain barrier (BBB) properties which, as a system, experiences impairment in several neurological and psychiatric diseases, and contributes to pathogenesis. To better understand function and dysfunction at the NVU, isolation and characterization of the NVU is needed. Here, we describe a singular, standardized protocol to enrich and isolate microvessels from archived snap-frozen human and frozen mouse cerebral cortex using mechanical homogenization and centrifugation-separation that preserves the structural integrity and multicellular composition of microvessel fragments. For the first time, microvessels are isolated from postmortem vmPFC tissue and are comprehensively investigated using both RNA sequencing and Liquid Chromatography with tandem mass spectrometry (LC-MS-MS). Both the transcriptome and proteome are elucidated and compared, demonstrating that the isolated brain microvessel is a robust model for the NVU and can be used to generate highly informative datasets in both physiological and disease contexts.

neuroscience↗