Biology subjects

Boeckers, T.

Publications and source records attributed to Boeckers, T..

10 recordsLinked to original sources

bioRxiv2026

Herpes simplex virus infection promotes ALS pathology through ICP0-mediated PML body disruption

Transactive response DNA binding protein 43 kDa (TDP-43) pathology, is a central molecular hallmark of amyotrophic lateral sclerosis (ALS). However, the underlying triggers are incompletely understood. Here, we show that infection with herpes simplex virus (HSV) induces molecular hallmarks of ALS in various in vitro and in vivo models and is associated with an increased risk of ALS in human population data. German healthcare provider data (n = 238,440) and herpesvirus serology of an ALS patient and control cohort (n = 1,100) showed that HSV infection elevated the ALS risk by 210% and odds by [~]65%, respectively. On a molecular level, HSV infection promoted TDP-43 pathology in neuronal cell models, human iPSC-derived motoneurons and cerebral organoids, mice, and human tissue sections. This effect was triggered by HSV-1 or 2, but not by several other related herpesviruses. Mechanistically, the infected cell protein 0 (ICP0) of HSV-1/2 drives TDP-43 pathology by disturbance of promyelocytic leukemia nuclear bodies (PML-NBs), thereby abrogating TDP-43 SUMO2/3ylation. Taken together, we reveal a previously unrecognized association between HSV infection and ALS and clarify the underlying molecular mechanism that drives TDP-43 pathology. Our data may guide future studies into therapeutic and prophylactic interventions against ALS.

neuroscience↗

bioRxiv2026

Loss of C3 and CD14 reduces region-specific neuroinflammation in a murine polytrauma model

BackgroundTraumatic brain injury (TBI) together with non-cerebral injuries characterizes the TBI-polytrauma (P-TBI) constellation, which is associated with acute neurological deterioration, delirium and unfavourable prognosis. It is hypothesized that systemic inflammatory mediators my enhances the focal, cerebral neuroimmune reaction with overall detrimental consequences, in particular in terms of acute microglial reactivity. MethodsWe explored the role of the Complement factor 3 (C3) and of the TLR-co receptor cluster of differentiation (CD14) in a murine polytrauma model that involves a mild TBI together with femur fracture, blunt thorax trauma and resuscitated haemorrhagic shock, making use of mice genetically lacking either C3, CD14 or both. ResultsWe show that P-TBI results in a rapid (4h) and brain-wide induction of inflammatory cytokines, although with distinct profiles (TNF and CCL2 having brain-wide involvement and IL-1{beta} restricted to ipsilateral cortex and striatum). TNF and CCL2 mRNA as well as protein synthesis were upregulated in microglia upon P-TBI in cortex, hippocampus and striatum which was fully abolished in the C3-/-CD14-/-animals. The analysis of single-KO animals revealed that induction of TNF and CCL2 was prevented in animals lacking C3, but not CD14, in the contralateral cortex and striatum, with an abolishment in hippocampus in mice lacking both C3 and CD14. In the cortical area of focal lesion neither C3 nor CD14 affected the induction of pro-inflammatory cytokines. ConclusionThus, C3 and CD14 are dispensable for the acute cytokine response to P-TBI in the site of injury but play differential roles across the cortex, hippocampus and striatum for the induction of cytokines in the non-injured parenchyma and in particular in microglia. Thus, interventions on C3 (mainly) and/or CD14 may reduce the encephalopathy risk associated with P-TBI but not the acute response in the injury site, where additional DAMP signalling may offer redundant activation pathways.

neuroscience↗

bioRxiv2024

RIG-I mediated neuron-specific IFN type 1 signaling in FUS-ALS induces neurodegeneration and offers new biomarker-driven individualized treatment options for (FUS-)ALS

Recent research has demonstrated significant aberrant activation of the innate immune system in ALS model systems due to mutations in SOD1, TARDBP and C9orf72 through stimulation of the TBK1-IRF3 pathway. This pathway can be activated, for example, by cGAS-STING-dependent sensing of cytosolic DNA that accumulates as a result of chronic DNA damage and defective mitochondria, both of which have been identified as early pathology in FUS-ALS spinal motor neurons (sMNs). Therefore, we analysed innate immune pathways in isogenic and non-isogenic FUSmut iPSC-derived sMNs, which revealed upregulation of interferon-stimulated genes (ISGs) and activation of the TBK1-IRF3 pathway in FUSmut sMNs. Notably, we found evidence for accumulation of cytosolic dsRNA and its sensor RIG-I in FUS-ALS. RIG-I, but not MDA5, was found to be significantly upregulated in FUSmut sMNs, and siRNA-mediated knockdown abolished the increased IFN1 activation in FUSmut sMNs. In post-mortem analysis, RIG-I was highly expressed in the remaining -MNs. IFN treatment of FUSwt sMNs phenocopied the axonal degeneration of FUSmut sMNs. Mechanistically, DNA damage induction did not increase ISG expression, but dsRNA was increased in the mitochondria of FUSmut sMNs. Mitochondrial transcription, a known source of dsRNA, was found to be upregulated in compartmental axonal RNAseq analysis and its inhibition reduced ISGs in FUS-ALS sMNs. Furthermore, the JAK-STAT inhibitor ruxolitinib alleviated the upregulated ISG expression and reversed the axonal degeneration of sMNs. Finally, we analysed ISG expression in peripheral blood samples from 18 FUS-ALS patients, eight of whom had a significantly elevated interferon signature. Blood ISGs correlated with disease progression rate and negatively with disease duration. RIG-I-mediated innate immune activation in sMNs may be an interesting novel individualised biomarker-driven therapeutic target in (FUS-) ALS. A one-sentence summary of your paperRIG-I-I-mediated innate immune activation is found in FUS-ALS spinal motor neurons caused by cytosolic dsRNA accumulation due to mitochondrial transcriptional activation and is amenable to JAK-STAT inhibition and might thus be an interesting novel individualized biomarker-driven therapeutic approach in (FUS-) ALS

neuroscience↗

bioRxiv2024

FUS controls muscle differentiation and structure through LLPS mediated recruitment of MEF2 and ETV5

FUS is an RNA binding protein mutated in amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by progressive muscle weakness. We show that ALS-associated FUS mutations lead to ultrastructural defects in muscle of FUS-ALS patients, with disruption of sarcomeres and mitochondria. Studies in mouse and Drosophila models demonstrate an evolutionary-conserved cell autonomous function of FUS in muscle development. Mechanistically, FUS is required for transcription of MEF2 dependent genes, binds to the promoter of genes bound by ETS transcription factors in particular ETV5 and co-activates transcription of MEF2 dependent genes with ETV5. FUS phase separates with ETV5 and MEF2A, and MEF2A binding to FUS is potentiated by ETV5. Last, Etv5 haploinsufficiency exacerbates muscle weakness in a mouse model of FUS-ALS. These findings establish FUS as an essential protein for skeletal muscle structure through its phase separation-dependent recruitment of ETV5 and MEF2, defining a novel pathway compromised in FUS-ALS.

neuroscience↗

bioRxiv2024

The FGFR inhibitor Rogaratinib reduces microglia reactivity and synaptic loss in TBI

BackgroundTraumatic brain injury (TBI) induces an acute reactive state of microglia, which contribute to secondary injury processes through phagocytic activity and release of cytokines. Several receptor tyrosine kinases (RTK) are activated in microglia upon TBI, and their blockade may reduce the acute inflammation and decrease the secondary loss of neurons; thus RTKs are potential therapeutic targets. We have previously demonstrated that several members of the FGFR family are transiently phosporylated upon TBI; the availability for drug repurposing of FGFR inhibitors makes worthwhile the elucidation of the role of FGFR in the acute phases of the response to TBI and the effect of FGFR inhibition. MethodsA closed, blunt, weight-drop mild TBI protocol was employed. The pan-FGFR inhibitor Rogaratinib was administered to mice 30min after the TBI and daily up to 7 days post injury. Phosphor-RTK Arrays and proteomic antibody arrays were used to determine target engagement and large-scale impact of the FGFR inhibitor. pFGFR1 and pFGFR3 immunostaining were employed for validation. As outcome parameters of the TBI injury immunostainings for NeuN, VGLUT1, VGAT at 7dpi were considered. ResultsInhibition of FGFR during TBI restricted phosphorylation of FGFR1, FGFR3, FGFR4 and ErbB4. Phosphorylation of FGFR1 and FGFR3 during TBI was traced back to Iba1+ microglia. Rogaratinib substantially dowregulated the proteomic signature of the neuroimmunological response to trauma, including the expression of CD40L, CXCR3, CCL4, CCR4, ILR6, MMP3 and OPG. Protracted Rogaratinib treatment exhibited a neuroprotective effect on neuronal density at 7dpi and limited the loss of excitatory (vGLUT+) synapses. ConclusionThe FGFR family is involved in the early induction of reactive microglia in TBI. FGFR inhibition selectively prevented FGFR phosphorylation in the microglia, dampened the overall neuroimmunological response and enhanced the preservation of neuronal and synaptic integrity. Thus, FGFR inhibitors display potential as microglial modulators in TBI.

neuroscience↗

bioRxiv2023

Live cell imaging of ATP levels reveals metabolic compartmentalization within motoneurons and early metabolic changes in FUS ALS motoneurons.

Motoneurons are one of the highest energy demanding cell types and a primary target in Amyotrophic lateral sclerosis (ALS), a debilitating and lethal neurodegenerative disorder without currently available effective treatments. Disruption of mitochondrial ultra-structure, transport and metabolism is a commonly reported phenotype in ALS models and can critically affect survival and proper function of motor neurons. However, how changes in metabolic rates contribute to ALS progression are not fully understood yet. Here we utilize hiPCS derived motoneuron cultures and live imaging quantitative techniques to evaluate metabolic rates in Fused in Sarcoma (FUS)-ALS model cells. We show that differentiation and maturation of motoneurons is accompanied by an overall upregulation of mitochondrial components and significant increase in metabolic rates that corresponds to their high energy-demanding state. Detailed compartment-specific live measurements using a fluorescent ATP sensor and FLIM imaging show significantly lower levels of ATP in the somas of cells carrying FUS-ALS mutations. These changes lead to the increased vulnerability of disease motoneurons to further metabolic challenges with mitochondrial inhibitors and could be due to the disruption of mitochondrial inner membrane integrity and an increase in its proton leakage. Furthermore, our measurements demonstrate heterogeneity between axonal and somatic compartments with lower relative levels of ATP in axons. Our observations strongly support the hypothesis that mutated FUS impacts metabolic states of motoneurons and makes them more susceptible to further neurodegenerative mechanisms.

neuroscience↗

bioRxiv2022

Excessive self-grooming of Shank3 mutant mice is associated with gene dysregulation and imbalance between the striosome and matrix compartments in the striatum

Autism is characterised by atypical social communication and stereotyped behaviours. Mutations in the gene encoding the synaptic scaffolding protein SHANK3 are detected in 1-2% of patients with autism and intellectual disability (ID), but the mechanisms underpinning the symptoms remain largely unknown. Here, we characterised the behaviour of Shank3{Delta}11/{Delta}11 mice from three to twelve months of age. We observed decreased locomotor activity, increased stereotyped self-grooming and modification of socio-sexual interaction compared to wild-type littermates. We then used RNAseq on four brain regions of the same animals to identify differentially expressed genes (DEG). DEGs were identified mainly in the striatum and were associated with synaptic transmission (e.g. Grm2, Dlgap1), G-protein-signalling pathways (e.g. Gnal, Prkcg1, and Camk2g), as well as excitation/inhibition balance (e.g. Gad2). Downregulated and upregulated genes were enriched in the gene clusters of medium-sized spiny neurons expressing the dopamine 1 (D1-MSN) and the dopamine 2 receptor (D2-MSN), respectively. Several DEGs (Cnr1, Gnal1, Gad2, and Drd4) were reported as striosome markers. By studying the distribution of the glutamate decarboxylase GAD65, encoded by Gad2, we showed that the striosome compartment of Shank3{Delta}11/{Delta}11 mice was enlarged and displayed much higher expression of GAD65 compared to wild-type mice. Altogether, these results indicate altered gene expression in the striatum of SHANK3-deficient mice and strongly suggest, for the first time, that the impairment in behaviour of these mice are related to an imbalance striosomes/matrix.

neuroscience↗

bioRxiv2021

Met/HGFR triggers detrimental reactive microglia in TBI

The complexity of the signaling events, cellular responses unfolding in neuronal, glial and immune cells upon Traumatic brain injury (TBI) constitutes an obstacle in elucidating pathophysiological links and targets for intervention. We used array phosphoproteomics in a murine mild blunt TBI to reconstruct the temporal dynamics of tyrosine-kinase signaling in TBI and then to scrutinize the large-scale effects of the perturbation of cMet/HGFR, VEGFR1 and Btk signaling by small molecules. cMet/HGFR emerged as a selective modifier of the early microglial response, and cMet/HGFR blockade prevented the induction of microglial inflammatory mediators, of reactive microglia morphology and of TBI-associated responses in neurons, vessels and brain extracellular matrix. Acute or prolonged cMet/HGFR inhibition ameliorated neuronal survival and motor recovery. Early elevation of HGF itself in the CSF of TBI patients suggest that this mechanism has translational value in human subjects. Our findings identify cMet/HGFR as a modulator of early neuroinflammation in TBI with translational potential and indicate several RTK families as possible additional targets for TBI treatment. SummaryControlling neuroinflammation in neurotrauma is an important but unachieved goal. This study exploits a moderate TBI model and array-based proteomics to identify cMet as a new inducer of reactive microglia. A small-molecule inhibitor of cMet contains microglial reactivity, reduces neuronal and vascular alterations, limits behavioural disturbances and accelerates recovery. HighlightsO_LIMet is activated in microglia upon TBI and drives microglial reactivity. C_LIO_LIA Met inhibitor reduces motor dysfunction upon TBI and promotes recovery. C_LIO_LIBlockade of MET prevents the appearance of a reactive microglia. C_LIO_LIThe cMET inhibitor reduces the sub-acute neuronal loss after TBI. C_LI

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bioRxiv2021

Functional ultrasound imaging of recent and remote memory recall in the associative fear neural network in mice

Scientific AbstractEmotional learning and memory are affected in numerous psychiatric disorders. At a systems level, however, the underlying neural circuitry is not well defined. Rodent fear conditioning (FC) provides a translational model to study the networks underlying associative memory retrieval. In the current study, functional connectivity among regions related to the cue associative fear network were investigated using functional ultrasound (fUS), a novel imaging technique with great potential for detecting regional neural activity through cerebral blood flow. Behavioral fear expression and fUS imaging were performed one and thirty-one days after FC to assess recent and remote memory recall. Cue-evoked increases in functional connectivity were detected throughout the amygdala, with the lateral (LA) and central (CeA) amygdalar nuclei emerging as major hubs of connectivity, though CeA connectivity was reduced during remote recall. The hippocampus and sensory cortical regions displayed heightened connectivity with the LA during remote recall, whereas interconnectivity between the primary auditory cortex and temporal association areas was reduced. Subregions of the prefrontal cortex exhibited variable connectivity changes, where prelimbic connectivity with the amygdala was refined while specific connections between the infralimbic cortex and amygdalar subregions emerged during remote memory retrieval. Moreover, freezing behavior positively correlated with functional connectivity between hubs of the associative fear network, suggesting that emotional response intensity reflected the strength of the cue-evoked functional network. Overall, our data provide evidence of the functionality of fUS imaging to investigate the neural dynamics of memory encoding and retrieval, applicable in the development of innovative treatments for affective disorders. HighlightsFunctional ultrasound imaging can elucidate fear associated neural networks Freezing behavior correlates with cue-evoked functional connectivity changes The lateral and central amygdalar nuclei are major hubs in the fear network The hippocampus is active during recent and remote cued fear memory retrieval Connectivity profiles of the prelimbic and infralimbic areas vary in remote recall

neuroscience↗

bioRxiv2020

Shank2 expression identifies a subpopulation of glycinergic interneurons involved in nociception and altered in an autism mouse model

Patients suffering from Autism Spectrum Disorders (ASD) experience disturbed nociception in form of either hyposensitivity to pain or hypersensitivity and allodynia. We have determined that Shank2-KO mice, which recapitulate the genetic and behavioural disturbances of ASD, display increased sensitivity to formalin pain and thermal, but not mechanical allodynia. We demonstrate that high levels of Shank2 expression identifies a subpopulation of neurons in murine and human dorsal spinal cord, composed mainly by glycinergic interneurons and that loss of Shank2 causes the decrease in NMDAR in excitatory synapses on these inhibitory interneurons. In fact, in the subacute phase of the formalin test, glycinergic interneurons are strongly activated in WT mice but not in Shank2-KO mice. As consequence, nociception projection neurons in lamina I are activated in larger numbers in Shank2-KO mice. Our findings prove that Shank2 expression identifies a new subset of inhibitory interneurons involved in reducing the transmission of nociceptive stimuli and whose unchecked activation is associated with pain hypersensitivity. Thus, we provide evidence that dysfunction of spinal cord pain processing circuits may underlie the nociceptive phenotypes in ASD patients and mouse models.

neuroscience↗