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Biology subjects

Korin, B.

Publications and source records attributed to Korin, B..

5 recordsLinked to original sources

Circadian-Related Dynamics of the Endocannabinoid System in Male Mouse Brain

Endocannabinoids (eCBs) and related lipids play crucial roles in brain function, including the regulation of circadian rhythms and sleep. To comprehensively map these molecules, we employed liquid chromatography high-resolution tandem mass spectrometry (LC/HRMS/MS) to quantify 78 lipids across 14 families in seven brain areas of male mice at four time points throughout the day (every six hours), and during sleep initiation. We found that most eCBs from the fatty acids (FAs) family, particularly arachidonic acid (AA), were highly abundant in the mouse brain in all brain areas and during the circadian rhythm. High eCBs abundance was shown in deeper brain areas, while temporal differences using the Cosinor analysis revealed 26 eCBs behaving in a circadian rhythm response, with linolenic acid (LnA) being the only lipid to show rhythmicity across all brain areas. Sleep initiation (ZT1) was associated with increased N-acylphosphatidylethanolamine phospholipase D (NAPE-PLD) activity and N-acylethanolamide (NAE) levels in the cortex and hippocampus, while wake extension (WEx) altered 2-monoacylglycerol (2-MAG) metabolism and increased cannabinoid receptor 1 (CB1) expression. These findings provide a detailed lipidomic map of eCBs and related lipids in the male mouse brain, highlighting their area-specific distribution, circadian regulation, and involvement in sleep/wake transitions. Given the link between sleep disruption and neurodegeneration, future studies should investigate whether the observed eCB dysregulation contributes to sleep disturbances in these conditions, and if targeting these pathways offers novel therapeutic strategies. Significant StatementThis comprehensive study provides a high-dimensional map of eCBs and related lipids in the male mouse brain, revealing intricate spatial and temporal dynamics highlighting the role of these lipids in regulating fundamental physiological processes such as circadian rhythm and sleep.

neuroscience↗

Glomerular immune injury promotes anti-tumor activity

Recent evidence suggests that the interaction between the tumor microenvironment (TME) and systemic host environment can alter the host immune system to promote anti-tumor activity. Here, we investigated whether glomerular immune injury affects cancer progression. We used nephrotoxic serum nephritis (NTN), a model for glomerular immune injury, and followed it by cancer cell implantation. NTS-injected mice developed smaller primary tumors compared with controls. Tumors of NTS-injected mice had more activated CD8 T cells, suggesting a role for the immune system in the anti-tumor phenotype. Using RNA-seq data, we identified transcriptomic alterations in the bone marrow following NTN. Moreover, using scRNA-seq of white blood cells following NTN we found these transcriptomic alterations were reflected in {gamma}{delta} T cells and neutrophils. This is the first study to show that glomerular immune injury changes the transcription of cells in the bone marrow to advance anti-tumor activity. Our study highlights the pivotal role of BM-mediated transcriptional alterations underlying the enhanced host immunity to tumor growth.

cancer biology↗

Aging and senescence-associated analysis of the aged kidney glomerulus highlights the role of mesangial cells in renal aging

Most causes of chronic kidney disease begin with injury to the glomerulus and involve progressive loss of kidney function. The glomerulus is a capillary bed where blood filtration to produce urine in the kidney occurs. During aging, there is progressive loss of glomeruli and filtration capacity of the kidney because podocytes, the glomerular epithelial cell, are lost with aging and after injury. Podocytes cannot divide and therefore cannot be replaced. Our histological analysis confirmed the presence of glomerulosclerosis, generalized interstitial fibrosis and glomerular hypertrophy in the aged mouse kidney. One barrier to studies of glomeruli is their low frequency in the kidney, less than 1.5% of the cells, and as such, they are often underrepresented in whole kidney analyses. To address this challenge, we used both bulk and single cell RNA sequencing (scRNA-Seq) to characterize purified glomeruli from young and aged mice. Aged glomeruli displayed increased inflammation and expressed a variety of injury and senescence-associated markers, most notably in mesangial cells and macrophages. This increased expression of senescence markers in mesangial cells of aged kidneys suggests a potential cellular target to address age-related renal dysfunction and chronic kidney disease (CKD), which represent a tremendous unmet medical need.

cell biology↗

The renal capsule: a vibrant and adaptive cell environment of the kidney in homeostasis, disease and aging

The kidney is a complex organ that governs many physiological parameters. It is roughly divided into three parts, the renal pelvis, medulla, and cortex. Covering the cortex is the renal capsule, a serosal tissue that provides protection and forms a barrier for the kidney. Serosal tissues of many organs have been recently shown to play a vital role in homeostasis and disease. Analyses of the cells that reside in these tissues have identified distinct cell types with unique phenotypes. Here, we characterized this niche and found that it is mainly comprised of fibroblasts and macrophages, but also includes other diverse cell types. Characterizing renal capsule-associated macrophages, we found that they consist of a distinct subset (i.e., TLF+ macrophages) that is nearly absent in the kidney parenchyma. Injury, disease, and other changes that involve the kidney, affected the cell composition of the renal capsule, indicating its dynamic response to changes within the organ parenchyma. Lastly, we studied age-related changes in the renal capsule and found that aging affected the cell composition and inflammatory phenotype of macrophages, increased CD8 T cells and other lymphocyte counts, and promoted a senescence-associated phenotype in fibroblasts. Taken together, our data illustrate the complexity and heterogeneity of the renal capsule and its underlying changes during aging and disease, improving our understanding of the kidney serosa that may be valuable for novel renal therapies.

immunology↗

Remembering immunity: Neuronal ensembles in the insular cortex encode and retrieve specific immune responses

Increasing evidence indicates that the brain regulates peripheral immunity. Yet, it remains unclear whether and how the brain represents the state of the immune system. Here, we show that immune-related information is stored in the brains insular cortex (InsCtx). Using activity-dependent cell labeling in mice (FosTRAP), we captured neuronal ensembles in the InsCtx that were active under two different inflammatory conditions (DSS-induced colitis and Zymosan-induced peritonitis). Chemogenetic reactivation of these neuronal ensembles was sufficient to broadly retrieve the inflammatory state under which these neurons were captured. Thus, we show that the brain can encode and initiate specific immune responses, extending the classical concept of immunological memory to neuronal representations of immunity.

neuroscience↗