Application of CBD as an antioxidant agent for axonal fusion in Lewis rats

• Grant number: 25/13218-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2025
• End date: August 31, 2026
• Field of knowledge: Biological Sciences - Morphology - Anatomy
• Principal Investigator: Luciana Politti Cartarozzi
• Grantee: Flora Cardoso da Silveira
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Peripheral nerve injury, such as sciatic nerve damage, leads to loss of motor and sensory functions. Part of the natural response of the peripheral nervous system involves Wallerian degeneration of the axonal segments distal to the lesion. For functional recovery, complete axonal regeneration is required, which often fails to occur properly or in time, resulting in muscle atrophy. Neurorrhaphy, the surgical procedure currently used for nerve repair, does not prevent degeneration. Recent studies have proposed a novel repair technique, axonal fusion, which is based on the application of polyethylene glycol combined with Methylene Blue (MB) as an antioxidant, to prevent premature axonal sealing and thereby reduce degeneration. In this context, the technique opens new perspectives for exploring the role of other antioxidant agents. Thus, the present project aims to investigate the potential of cannabidiol (CBD) as an antioxidant in the axonal fusion process. To this end, female Lewis rats, approximately 8 weeks old, will be used and divided into the following experimental groups (n = 7/group): Neurorrhaphy, Axonal Fusion with MB, Axonal Fusion with CBDnano (a modified CBD tagged with Lumogen Red), and Axonal Fusion with vehicle control. For up to eight weeks, animals will be evaluated for functional recovery through gait analysis using the CatWalk system, and motor reinnervation will be assessed by electroneuromyography. At the end of the experimental period, animals will be perfused and sciatic nerves collected for Sudan Black staining (myelin assessment) and immunofluorescence, targeting markers for axons (neurofilament), Schwann cells (S-100), motor axons (ChAT), and sensory axons (VGluT-1). (AU)