Neuroimmune and Neuropathic Responses of Spinal Cord and Dorsal Root Ganglia in Middle Age

摘要: Prior studies of aging and neuropathic injury have focused on senescent animals compared to young adults, while changes in middle age, particularly the dorsal root ganglia (DRG), remained largely unexplored. 14 neuroimmune mRNA markers, previously associated with peripheral nerve injury, were measured multiplex assays lumbar spinal cord (LSC), DRG from middle-aged (3, 17 month) naive rats, or rats subjected chronic constriction (CCI) sciatic (after 7 days), aged-matched sham controls. Results showed that CD2, CD3e, CD68, CD45, TNF-α, IL6, CCL2, ATF3 TGFβ1 levels substantially elevated LSC adults. Similarly, samples older increased T-cell microglial/macrophage markers. CCI induced further increases Immunofluorescence images horn microglia typically hypertrophic mostly thickened, de-ramified processes, similar following CCI. Unlike cord, marker expression profiles unchanged across age (except ATF3); whereas, GFAP protein, localized satellite glia, highly but independent injury. Most markers yet little response No age-related nociception (heat, cold, mechanical) observed at days 3 post-CCI. The patterns microglial morphologies healthy are consistent development a para-inflammatory state involving activation elevation horn, neuronal stress cell DRG. These changes, however, did not affect establishment pain.