Biology subjects

Wunnemann, F.

Publications and source records attributed to Wunnemann, F..

3 recordsLinked to original sources

bioRxiv2023

Metabolic Reprogramming of the Neovascular Niche Promotes Regenerative Angiogenesis in Proliferative Retinopathy

Healthy blood vessels supply neurons to preserve metabolic function. In blinding ischemic proliferative retinopathies (PRs), pathological neovascular tufts often emerge in lieu of needed physiological neuroretina revascularization. We show that metabolic shifts in the neurovascular niche define this angiogenic dichotomy between healthy and diseased blood vessel growth. Fatty acid oxidation (FAO) metabolites accumulated in human and murine retinopathy samples. Neovascular tufts with a distinct single-cell transcriptional signature highly expressed FAO enzymes. The deletion of Sirt3, an FAO regulator, shifted the neurovascular niche metabolism from FAO to glycolysis and suppressed tuft formation. This metabolic transition increased Vegf expression in astrocytes and reprogrammed pathological EC to a physiological phenotype, hastening vascular regeneration of the ischemic retina. Our findings identify SIRT3 as a metabolic switch in the neurovascular niche, offering a new therapeutic target for optimizing ischemic tissue revascularization. HighlightsO_LIPathological EC favor FAO over glycolysis. C_LIO_LIUnique signature for pathological EC found in proliferative retinopathy model. C_LIO_LISirt3 deletion shifts astrocytes and EC metabolism from FAO to glycolysis. C_LIO_LIMetabolic reprogramming of the vascular niche enhances physiological revascularization. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=83 SRC="FIGDIR/small/566898v1_ufig1.gif" ALT="Figure 1"> View larger version (21K): org.highwire.dtl.DTLVardef@70020eorg.highwire.dtl.DTLVardef@19719acorg.highwire.dtl.DTLVardef@1168ddeorg.highwire.dtl.DTLVardef@1bc25e0_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2022

Enhancing adult neuroplasticity by epigenetic regulation of Parvalbumin-expressing GABAergic cells

Failure of inhibiting fear in response to harmless stimuli contributes to anxiety disorders. Extinction training only temporarily suppresses fear memories in adults, but it is highly effective in juveniles. GABAergic parvalbumin-positive (PV+) cells restrict plasticity in adult brains, thus increasing PV+ cell plasticity could promote the suppression of fear memories following extinction training in adults. Histone deacetylase 2 (Hdac2) restrains both structural and functional synaptic plasticity; however, whether and how Hdac2 controls adult PV+ cell plasticity is unknown. Here, we report that Hdac2 deletion or pharmacological inhibition in PV+ cells attenuate spontaneous recovery of fear memory after fear extinction learning in adults. These manipulations promote a temporally restricted downregulation of Acan, a critical perineuronal net component expressed exclusively by PV+ cells in medial prefrontal cortex. Finally, we show that Acan transient downregulation before extinction training but after fear memory acquisition is sufficient to reduce spontaneous fear memory recovery in wild-type mice.

neuroscience↗

bioRxiv2020

A 4-lineage statistical suite to evaluate the support of large-scale retrotransposon insertion data to reconstruct evolutionary trees

Retrophylogenomics makes use of genome-wide retrotransposon presence/absence insertion patterns to resolve questions in phylogeny and population genetics. In the genomics era, evaluating high-throughput data requires the associated development of appropriately powerful statistical tools. The currently used KKSC 3-lineage statistical test for estimating the significance of retrophylogenomic data is limited by the number of possible tree topologies it can assess in one step. To improve on this, we have extended the analysis to simultaneously compare 4-lineages, enabling us to evaluate ten distinct presence/absence insertion patterns for 26 possible tree topologies plus 129 trees with different incidences of hybridization or introgression. The new tool provides statistics for cases involving multiple ancestral hybridizations/introgressions, ancestral incomplete lineage sorting, bifurcation, and polytomy. The test is embedded in a user-friendly web R-application (http://retrogenomics.uni-muenster.de:3838/hammlet/) and is available for use by the scientific community.

evolutionary biology↗