Purinergic-associated immune responses in neurodegenerative diseases.

The chronic activation of immune cells can participate in the development of pathological conditions such as neurodegenerative diseases including Alzheimer's disease (AD), Multiple Sclerosis (MS), Parkinson's disease (PD), Huntington's disease (HD) and Amyotrophic Lateral Sclerosis (ALS). In recent years, compelling evidence indicates that purinergic signaling plays a key role in neuro-immune cell functions. The extracellular release of adenosine 5'-triphosphate (ATP), and its breakdown products (ADP and adenosine) provide the versatile basis for complex purinergic signaling through the activation of several families of receptors.

P2X4 signalling contributes to hyperactivity but not pain sensitization comorbidity in a mouse model of attention deficit/hyperactivity disorder.

Attention deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder characterized by hyperactivity, inattention, and impulsivity that often persist until adulthood. Frequent comorbid disorders accompany ADHD and two thirds of children diagnosed with ADHD also suffer from behavioural disorders and from alteration of sensory processing. We recently characterized the comorbidity between ADHD-like symptoms and pain sensitisation in a pharmacological mouse model of ADHD, and we demonstrated the implication of the anterior cingulate cortex and posterior insula.

Microglial P2X4 receptors are essential for spinal neurons hyperexcitability and tactile allodynia in male and female neuropathic mice.

In neuropathic pain, recent evidence has highlighted a sex-dependent role of the P2X4 receptor in spinal microglia in the development of tactile allodynia following nerve injury. Here, using internalization-defective P2X4mCherryIN knockin mice (P2X4KI), we demonstrate that increased cell surface expression of P2X4 induces hypersensitivity to mechanical stimulations and hyperexcitability in spinal cord neurons of both male and female naive mice. During neuropathy, both wild-type (WT) and P2X4KI mice of both sexes develop tactile allodynia accompanied by spinal neuron hyperexcitability.

Purine Biosynthesis Pathways Are Required for Myogenesis in .

Purines are required for fundamental biological processes and alterations in their metabolism lead to severe genetic diseases associated with developmental defects whose etiology remains unclear. Here, we studied the developmental requirements for purine metabolism using the amphibian as a vertebrate model. We provide the first functional characterization of purine pathway genes and show that these genes are mainly expressed in nervous and muscular embryonic tissues.

A photoswitchable inhibitor of TREK channels controls pain in wild-type intact freely moving animals.

By endowing light control of neuronal activity, optogenetics and photopharmacology are powerful methods notably used to probe the transmission of pain signals. However, costs, animal handling and ethical issues have reduced their dissemination and routine use. Here we report LAKI (Light Activated K channel Inhibitor), a specific photoswitchable inhibitor of the pain-related two-pore-domain potassium TREK and TRESK channels.