Dataset Information

Hyaluronan-based extracellular matrix under conditions of homeostatic plasticity.

ABSTRACT: Neuronal networks are balanced by mechanisms of homeostatic plasticity, which adjusts synaptic strength via molecular and morphological changes in the pre- and post-synapse. Here, we wondered whether the hyaluronic acid-based extracellular matrix (ECM) of the brain is involved in mechanisms of homeostatic plasticity. We hypothesized that the ECM, being rich in chondroitin sulfate proteoglycans such as brevican, which are suggested to stabilize synapses by their inhibitory effect on structural plasticity, must be remodelled to allow for structural and molecular changes during conditions of homeostatic plasticity. We found a high abundance of cleaved brevican fragments throughout the hippocampus and cortex and in neuronal cultures, with the strongest labelling in perineuronal nets on parvalbumin-positive interneurons. Using an antibody specific for a brevican fragment cleaved by the matrix metalloprotease ADAMTS4, we identified the enzyme as the main brevican-processing protease. Interestingly, we found ADAMTS4 largely associated with synapses. After inducing homeostatic plasticity in neuronal cell cultures by prolonged network inactivation, we found increased brevican processing at inhibitory as well as excitatory synapses, which is in line with the ADAMTS4 subcellular localization. Thus, the ECM is remodelled in conditions of homeostatic plasticity, which may liberate synapses to allow for a higher degree of structural plasticity.

SUBMITTER: Valenzuela JC

PROVIDER: S-EPMC4173291 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Hyaluronan-based extracellular matrix under conditions of homeostatic plasticity.

Valenzuela Juan Carlos JC Heise Christopher C Franken Gilbert G Singh Jeet J Schweitzer Barbara B Seidenbecher Constanze I CI Frischknecht Renato R

Philosophical transactions of the Royal Society of London. Series B, Biological sciences 20141001 1654

Neuronal networks are balanced by mechanisms of homeostatic plasticity, which adjusts synaptic strength via molecular and morphological changes in the pre- and post-synapse. Here, we wondered whether the hyaluronic acid-based extracellular matrix (ECM) of the brain is involved in mechanisms of homeostatic plasticity. We hypothesized that the ECM, being rich in chondroitin sulfate proteoglycans such as brevican, which are suggested to stabilize synapses by their inhibitory effect on structural pl ...[more]

PMID: 25225099

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Dataset Information

Hyaluronan-based extracellular matrix under conditions of homeostatic plasticity.

Publications

Hyaluronan-based extracellular matrix under conditions of homeostatic plasticity.

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