Immunomodulation by 4-hydroxy-tempo (TEMPOL) after ventral root crush in mice C57BL/6J

Abstract

Spinal nerve root lesions can occur after trauma and pathological processes, leading to dysfunction of brachial and lumbosacral plexuses. These lesions can be avulsion or crush, generating neuronal death and synaptic loss, consequently, causing motor and sensory dysfunctions. Local inflammation is mediated by astroglial and microglial cells, giving rise to a pro-inflammatory profile. Drugs with immunomodulatory and neuroprotective potential can minimize or prevent damage after injury to neuronal tissue. Tempol is a drug that has been studied in our laboratory in spinal cord nerve root injuries and has demonstrated excellent results in terms of neuroprotection and immunomodulation, decreasing the inflammation process through its antioxidant action. Thus, we aim to evaluate the time course of the immunomodulatory role of Tempol after ventral root crush in mice. For that, flow cytometry will be used, evaluating in a multiparametric way, different pro- and anti-inflammatory glial markers. For that, two experimental groups, vehicle and Tempol will be set at a dose of 50mg/kg, being analyzed during three different times, 7, 14 and 28 days after injury. After root injury and the appropriate survival times, the animals will be submitted to an overdose of anesthetic, followed by thorocotomy and transcardiac perfusion with buffered saline. In sequence, the flow cytometry protocol will be performed for cell phenotyping. A panel of antibodies will be used for profiling microglial cells and astrocytes, in addition to lymphocytes. Emphasis will be given to the M1/M2 and A1/A2 polarization, focusing on the immunomodulatory role of Tempol treatment.