Biology subjects

Thouaye, M.

Publications and source records attributed to Thouaye, M..

3 recordsLinked to original sources

bioRxiv2023

FLT3 signaling inhibition preserves opioid analgesia while abrogating tolerance and hyperalgesia

Opioid analgesia is counteracted on chronic use by tolerance and hyperalgesia inducing dose escalation and life-threatening overdoses. Mu opiate receptors (MOR) expressed in primary sensory neurons were recently found to control tolerance and hyperalgesia, but the underlying mechanisms remained elusive. Here we show that genetic inactivation of fms-like tyrosine kinase receptor 3 (FLT3) receptor in sensory neurons abrogates morphine tolerance and hyperalgesia by preventing MOR-induced hyperactivation of the cAMP signaling pathway and subsequent excitatory adaptive processes. Moreover, the specific FLT3 inhibitor BDT001 potentiates morphine analgesia in acute and chronic pain models, without aggravating morphine adverse effects, and reverses tolerance and hyperalgesia once installed. Thus, FLT3 appears as a key regulator of the MOR signaling pathway and its pharmacological blockade shows promise to enhance chronic opioid analgesic efficacy.

neuroscience↗

bioRxiv2021

Activation of peripheral neuronal FLT3 promotes exaggerated sensorial and emotional pain-related behaviors facilitating the transition from acute to chronic pain

Acute pain events have been associated with persistent pain sensitization of nociceptive pathways increasing the risk of transition from acute to chronic pain. However, it is unclear whether injuryinduced persistent pain sensitization can promote long-term mood disorders. The receptor tyrosine kinase FLT3 is causally required for pain chronification after peripheral nerve injury, questioning its role in the development of pain-induced mood alterations. Here, we evaluated the emotional and sensorial components of pain after a single (SI) or double paw incision (DI). We then investigated the role of FLT3 either by inhibition using transgenic knock-out mice and functional antibodies or by activation with FLT3 ligand (FL) administrations. DI mice showed significant anxiodepressive-like and spontaneous pain behaviors as opposed to SI mice. DI also promoted and extended mechanical pain hypersensitivity compared to SI. This emotional and sensorial pain exaggeration correlated with spinal changes especially by increased microglia activation after DI versus SI. Intrathecal minocycline, a microglial inhibitor, specifically reversed DI inducedmechanical hypersensitivity in males. Repeated treatment with the microglia proliferation inhibitor GW2580 not only eliminated the exaggerated pain hypersensitivity produced by DI but also prevented anxiodepressive-related behaviors in DI animals. Finally, FL injections in naive animals provoked mechanical allodynia and anxiodepressive-like disorders concomitant with a strong microglial activation while Flt3 silencing in a genetic mouse line or FLT3 blocking via functional antibodies, blunted the development of persistent pain and depression after DI. Altogether our results show that the repetition of peripheral lesions facilitate not only exaggerated nociceptive behaviors but also induced anxiodepressive disorders supported by spinal central changes. The inhibition of FLT3 could thus become a promising therapy in the management of pain sensitization and related mood alterations.

neuroscience↗

bioRxiv2021

Modulation of hippocampal network oscillation by PICK1-dependent cell surface expression of mGlu3 receptors

mGlu3 receptors control the sleep/wake architecture which plays a role in the glutamatergic pathophysiology of schizophrenia. Interestingly, mGlu3 receptors expression is decreased in the brain of schizophrenic patients. However, little is known about the molecular mechanisms regulating mGlu3 receptors at the cell membrane. Subcellular receptor localization is strongly dependent on proteinprotein interactions. Here we show that mGlu3 interacts with PICK1 and that their binding is important for receptor surface expression and function. Disruption of their interaction via an mGlu3 C-terminal mimicking peptide or an inhibitor of the PDZ domain of PICK1 altered the functional expression of mGlu3 receptors. Consequently, we investigated whether disruption of the mGlu3-PICK1 interaction affects hippocampal theta oscillations in vitro and in vivo. We found a decreased frequency of theta oscillations in organotypic hippocampal slices, similar to what previously observed in mGlu3 -/- mice. In addition, hippocampal theta power was reduced during REM sleep, NREM sleep and wake states after intra-ventricular administration of the mGlu3 C-terminal mimicking peptide. Targeting the mGlu3-PICK1 complex could thus be relevant to the pathophysiology of schizophrenia.

neuroscience↗