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Biology subjects

Chintawar, S.

Publications and source records attributed to Chintawar, S..

3 recordsLinked to original sources

BNIP3L/NIX-mediated mitophagy limits Alzheimer disease pathology and preserves neuronal function

Defective mitophagy is emerging as a key contributor to Alzheimer disease (AD), but the neuronal pathways governing mitochondrial clearance and their contribution to disease progression remain poorly understood. Here, we identify BNIP3L/NIX-dependent mitophagy as a conserved neuronal quality control pathway that maintains mitochondrial fitness and constrains AD-associated proteotoxicity. Loss of BNIP3L/NIX or its C. elegans orthologue DCT-1 impaired basal and stressed-induced mitophagy, disrupted mitochondrial homeostasis, enhanced Tau and Amyloid-beta pathology and compromised neuronal network, synaptic and behavioral function across human neuronal and in vivo models. Conversely, restoring BNIP3L/NIX and DCT-1 activity improved neuronal function under proteotoxic stress in vivo, reduced disease-associated Tau phosphorylation in human neurons and markedly suppressed seeded Tau aggregation in primary mouse neurons. Together, these findings identify BNIP3L/NIX-mediated mitophagy as a mechanistic link between mitochondrial quality control, proteostasis and neuronal function, and establish its restoration as a potential strategy for counteracting AD-associated pathology.

cell biology↗

When Animals Turn Inside Out: The Eversion of Bloodworms

Bloodworms, Glycera dibranchiata, possess an eversible proboscis that normally remains concealed within their bodies but explosively everts if the worm attacks or burrows. How does the bloodworm evert quickly and reliably? In a series of experiments, we characterize bloodworm kinematics, pressure, and material properties to estimate the criteria for eversion safely without rupture of the proboscis. We predict the proboscis can withstand pressures 50 times higher and bending strains up to three times higher than the respective values observed. We also present a dimensional analysis of eversion, finding that everting animals, from frogs to snails to sharks, do not satisfy Froudes law for equivalence of velocities. Our findings may help inspire the development of pressure-driven soft robots with efficient retraction capabilities.

biophysics↗

A highly efficient method to differentiate CGRP-expressing peptidergic nociceptors from human induced pluripotent stem cells

Human cellular models of disease developed using induced pluripotent stem cells (iPSC) have enabled wide-ranging research from investigation of human disease mechanisms to phenotypic drug screens. Pain disorders such as neuropathic pain and headache remain areas of considerable unmet need and are considered high risk by pharma. Human iPSC-derived sensory neurons have already been used to accelerate translational research but the current differentiation protocols produce non-peptidergic nociceptors. We demonstrate for the first time the robust differentiation of hiPSC into peptidergic nociceptor lineage with high yield. These nociceptors express CGRP and TRPV1 whilst the non-peptidergic marker RET was completely absent. Functionally, the nociceptors show functional maturity including the expression of TTX-resistant currents and responding to TRPV1 and TRPA1 agonists. Importantly, they were able to release CGRP basally and upon stimulation by an inflammatory soup, which was inhibited upon the application of the 5-HT1B/1D/1F agonist, sumatriptan and topiramate, a migraine prophylactic drug. Overall, we report the successful generation of a novel in vitro functional peptidergic nociceptor model which will allow investigation of disease mechanisms in pain and for the development of new effective pain therapies.

neuroscience↗