Cortical repercussions of proximal axotomy of spinal motoneurons: focus on the glial response

• Grant number: 25/16144-9
• 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: Marcelo Carvalho Mariano Junior
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 22/06609-6 - Glutamatergic signaling after rachimedullary trauma: role of glial cells in the inflammatory response and excitotoxicity, AP.GR

Abstract

Proximal axotomies, such as Ventral Root Crush (VRC), lead to the degeneration of up to 50% of affected motoneurons within the first weeks following injury, resulting in significant functional deficits. In addition to neuronal death, a strong reactive gliosis occurs, characterized by morphofunctional changes in glial cells surrounding the injured motoneurons.Although the spinal alterations resulting from VRC have been well characterized, the effects of such lesions on the primary motor cortex (M1) remain poorly explored. Recent evidence suggests that peripheral nerve injuries may impact M1, promoting a transient reduction in synaptic density and an increase in microglial reactivity, indicating a potential functional communication pathway.In this context, the present project aims to characterize the glial response in the primary motor cortex over time after VRC, through the analysis of GFAP (astrocyte marker) and Iba-1 (microglia marker) expression at 1, 3, 5, 7, 14, and 28 days post-lesion. (AU)