Biology subjects

Kondrakiewicz, L.

Publications and source records attributed to Kondrakiewicz, L..

5 recordsLinked to original sources

bioRxiv2025

The Role of TCF7L2 in Regulating Energy Metabolism in Thalamocortical Circuitry and its Broader Impact on Social Behavior

Psychiatric and metabolic disorders often co-occur. While shared genetic factors and cellular dysfunctions are implicated, the underlying molecular mechanisms remain poorly understood. TCF7L2, a risk gene for type 2 diabetes and autism spectrum disorder, is highly expressed in the thalamus--a brain region extensively interconnected with the cortex, playing a key role in sensory processing, motor control, and behavioral regulation. Given its known role as a transcription factor regulating systemic energy metabolism, we explored its potential contribution to brain metabolism and behavior. To this end, we used a conditional knockout model with postnatal TCF7L2 loss in the thalamus and partial deficiency in the pancreas. Tcf7l2 knockout mice exhibited social deficits and reduced motor habituation. In parallel, they also developed systemic glucose intolerance, modelling the psychiatric-metabolic comorbidity. Thalamic depletion of TCF7L2 resulted in elevated inhibitory phosphorylation of the pyruvate dehydrogenase --an enzymatic gatekeeper for pyruvate utilization in energy production--in the thalamus and cortex. This was accompanied by altered thalamic and cortical metabolism, characterized by reduced efficiency of pyruvate oxidation alongside enhanced oxidation of fatty acids and ketone bodies. Notably, a ketogenic diet alleviated metabolic dysregulation in the brain and normalized some social behaviors in knockout mice. These findings suggest that impaired energy metabolism in the thalamocortical circuitry may represent one of the pathogenic mechanisms underlying neuropsychiatric symptoms.

neuroscience↗

bioRxiv2023

Mutation in mitochondrial chaperone TRAP1 results in male-specific autism

There is increasing evidence of mitochondrial dysfunction in autism spectrum disorders (ASD), but the causal relationships are unclear. In an ASD patient whose identical twin was unaffected, we identified a postzygotic mosaic mutation p.Q639* in the TRAP1 gene, which encodes a mitochondrial chaperone of the HSP90 family. Additional screening of 176 unrelated ASD probands revealed an identical TRAP1 variant in a male patient who had inherited it from a healthy mother. Notably, newly generated knock-in Trap1 p.Q641* mice display ASD-related behavioral abnormalities exclusively in males. Accordingly, Trap1 p.Q641* mutation also resulted in sex-specific changes in synaptic plasticity, number of presynaptic mitochondria, and metabolic substrate consumption. Thus, the TRAP1 p.Q639* mutation is the first example of a monogenic ASD caused by impaired mitochondrial protein homeostasis. One-Sentence SummaryPatient mutation in TRAP1 causes autism in male mice.

neuroscience↗

bioRxiv2021

Social learning about rewards: how information from others helps to adapt to changing environment

Being a part of a social structure is key for survival and reproduction. Living with conspecifics boosts evolutionary fitness, by providing essential information about the environment. Nonetheless, studying neural mechanisms of social learning has not yet been established under laboratory conditions. To examine how socially passed information about the reward affects the behavior of individuals we used Eco-HAB, an automated system for tracing voluntary behavior of group-housed mice living under semi-naturalistic conditions. We show that a scent of a rewarded individual has profound effects on the conspecifics ability to find the reward in both familiar and novel environments. Importantly, the animals display clear and stable individual differences in social behavior. As a result, socially conveyed information has different effects on individual mice. Further, we show that disrupting neuronal plasticity in the prelimbic cortex with nanoparticles gradually releasing TIMP metallopeptidase inhibitor 1, disrupts animals social behavior and results in decreased ability to adapt to environmental changes. The experimental paradigm we developed can be further used to study neuronal mechanisms of social learning.

neuroscience↗

bioRxiv2020

Serum response factor is essential for synaptic maturation in the hippocampus

Disturbances of gene expression patterns that occur during brain development can severely affect signal transmission, connectivity, and plasticity--key features that underlie memory formation and storage in neurons. Abnormalities at the molecular level can manifest as changes in the structural and functional plasticity of dendritic spines that harbor excitatory synapses. This can lead to such developmental neuropsychiatric conditions as Autism spectrum disorders, intellectual disabilities, and schizophrenia. The present study investigated the role of the major transcriptional regulator serum response factor (SRF) in synapse maturation and its impact on behavioral phenotypes. Using in vitro and in vivo models of early postnatal SRF deletion, we studied its influence on key morphological and physiological hallmarks of spine development. The elimination of SRF in developing neurons resulted in a phenotype of immature dendritic spines and impairments in excitatory transmission. Moreover, using a combination of molecular and imaging techniques, we showed that SRF-depleted neurons exhibited a lower level of specific glutamate receptor mRNAs and a decrease in their surface expression. Additionally, the early postnatal elimination of SRF in hippocampal CA1 excitatory neurons caused spine immaturity and a specific social deficit that is frequently observed in autism patients. Altogether, our data suggest that the regulation of structural and functional dendritic spine maturation begins at the stage of gene transcription, which underpins the crucial role of such transcription factors as SRF. Moreover, disturbances of the postnatal expression of SRF translate to behavioral changes in adult animals.

neuroscience↗

bioRxiv2020

β-catenin signaling via astrocyte-encoded TCF7L2 regulates neuronal excitability and social behavior

Astrocytes play essential roles in supporting neuronal activity and synapse formation; however, mechanisms by which these functions are regulated are unclear. The Wnt/{beta}-catenin signaling pathway plays a crucial role in brain development and is implicated in neurodevelopmental disorders including autism spectrum disorder (ASD). We sought to investigate if some impacts of Wnt signaling are mediated via astrocytes. Here we show that the canonical Wnt/{beta}-catenin pathway is active in postnatal cortical astrocytes and that its effector, the transcription factor TCF7L2 -is expressed in astrocyte lineage cells during embryonic and postnatal development in both mouse and human. Astrocyte-specific deletion of Tcf7l2 in the early postnatal period led to alterations in astrocyte morphology, membrane depolarization and decreased cortical neuron excitability. Mice with the conditional knockout exhibited increased sociability and social preference in a naturalistic setting. Taken together, these data reveal a key role of astrocytic Wnt signaling in shaping postnatal neuronal development and adult social behavior.

neuroscience↗