Biology subjects

Deepak, S.

Publications and source records attributed to Deepak, S..

3 recordsLinked to original sources

bioRxiv2024

Neuronally differentiated endothelial cell subtype regulates organ blood flow and immune balance

Vascular endothelial cells (ECs) perform key pleiotropic functions to maintain body homeostasis via the regulation of organ blood flow, vascular permeability, tissue growth and inflammation, and angiogenesis. Recent transcriptomic studies uncovered many EC subtypes across organs; however their specific functions are incompletely understood. Here we identified and characterized a novel, minority subtype of scattered ECs with a well-defined arteriovenous zonal localization exclusively in small resistance (strain) arterioles, and with the highest density in the brain>retina>kidney. Due to their expression of both endothelial and neuron-like functional and gene transcriptomic signatures, they were termed neuro-endothelial cells (NECs). High resolution single-cell transcriptome analysis of mouse brain and kidney ECs identified neuronal nitric oxide synthase (Nos1) and cytokine-like 1 (Cytl1) as top NEC biomarkers. Intravital multiphoton imaging of optogenetic mouse models with NEC gain/loss-of-function revealed NEC and Nos1-dependent vasodilation/vasoconstriction of intact brain and kidney arterioles and elevation/reduction in blood flow. Silencing NEC Nos1 and Cytl1 gene expression in vivo caused marked segmental arteriolar vasoconstrictions, reductions in vascular density and organ blood flow, increased vascular permeability and immune cell homing. Cytl1 administration triggered vasodilation and increased blood flow acutely, and increased capillary density and clonal EC remodeling chronically. NECs play major vasodilatory, angiogenic and anti-inflammatory functions that may be therapeutically targeted for vascular and inflammatory diseases.

physiology↗

bioRxiv2021

Physiological activation of the nephron central command drives endogenous kidney tissue regeneration

Tissue regeneration is limited in several organs including the kidney, contributing to the high prevalence of kidney disease globally. However, evolutionary and physiological adaptive responses and the presence of renal progenitor cells suggest existing remodeling capacity. This study uncovered a novel endogenous tissue remodeling mechanism in the kidney that is activated by the loss of body fluid and salt and involves a unique niche of chief cells called macula densa (MD) that control resident progenitor cells via secreted angiogenic, growth and extracellular matrix remodeling factors, cytokines and chemokines. Serial intravital imaging, MD Wnt mouse models and transcriptome analysis provide functional and molecular characterization of this newly identified MD program for kidney regeneration complemented with human and therapeutic translation. The concept that chief cells responding to organ-specific physiological inputs control local progenitors and direct them to remodel or repair tissues may be applicable to other organs and diverse tissue regenerative therapeutic strategies.

physiology↗

bioRxiv2021

Neuron-like function of the nephron central command

Interoceptive neurons that sense and regulate our internal milieu have been identified in several organs except in the kidney cortex despite its major importance in maintaining body homeostasis. Here we report that the chief kidney cell type of the macula densa (MD) forms coordinated neural networks in each nephron that resemble peripheral ganglia. A combined in vivo single-cell 4D physiology (sc4DP) and scRNA sequencing approach identified the MD mechanisms of neuronal differentiation, heterogeneity (pacemaker MD cells), sensing of the local and systemic environment via multi-organ crosstalk, and regulation of organ functions by acting as the nephron central command. Consistent with their neuron-like nature, MD cells express the molecular fingerprint of neurodegeneration. Here we put forth the single-cell MD model and concept of local neural networks that control organ and body functions via interoception in normal physiological state and use an integrated mechanism of neurodegeneration in disease.

physiology↗