Effects of neurostimulation and psychopharmacological treatment with cannabidiol in the infralimbic cortex on chronic pain, neuromolecular changes and comorbidities associated with fibromyalgia

• Grant number: 24/06346-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2024
• End date: June 30, 2025
• Field of knowledge: Health Sciences - Medicine - Psychiatry
• Principal Investigator: Renato Leonardo de Freitas
• Grantee: Railson Carlos Olinto de Brito
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Introduction: Fibromyalgia (FM) is a syndrome characterized by widespread chronic pain (CD), in addition to comorbidities that negatively impact quality of life. Deep brain stimulation (DBS) of the medial prefrontal cortex (MPFC), a region involved in the cognitive, emotional and affective aspects of pain, has been an emerging alternative for the treatment of CD. Furthermore, cannabidiol (CBD) has also been widely studied as an alternative in the treatment of comorbidities of CD and FM. Objective: To study the neurobiological and psychopharmacological bases of FM through the use of DBS and CBD treatment in the infralimbic division of the CPFM (IFL/CPFM), evaluating the effects on CD, depression and cognitive impairments in an animal model of FM. Methods: The animal model that will be used will be the reserpine-induced FM model. For this, the medicine will be administered to male Wistar rats [1 ml/kg (SC) once a day for 3 consecutive days]. DBS will follow the parameters of 20 µA/15s/100 Hz. CBD treatment will be carried out at concentrations of 15, 30 or 60 nmol. The nociceptive tests will be the von Frey and acetone tests; behavioral tests: open field, forced swimming, sucrose spray and object recognition. Neuromolecular assessment will include NeuN, DCX, GFAP labeling and identification of CB1 receptors. Hypothesis: DBS and CBD treatment in IFL/CPFM will trigger behavioral and neuromolecular changes associated with reduced CD, depression and cognitive impairment.