RESUMO
Peripheral nerve injury still remains a refractory challenge for both clinical and basic researchers. A novel nanofiber conduit made of blood vessel and filled with amphiphilic hydrogel of self-assembling nanofiber scaffold (SAPNS) was implanted to repair a 10 mm nerve gap after sciatic nerve transection. Empty blood vessel conduit was implanted serving as control. Results showed that this novel nanofiber conduit enabled the peripheral axons to regenerate across and beyond the 10 mm gap. Motoneuron protection, axonal regeneration and remyelination were significantly enhanced with SAPNS scaffold treatments. The target reinnervation and functional recovery induced by the regenerative nerve conduit suggest that SAPNS-based conduit is highly promising application in the treatment of peripheral nerve defect. FROM THE CLINICAL EDITOR: In this paper by Zhan et al, a novel self-assembling nanofiber scaffold is reported to promote regeneration of peripheral nerves in a sciatic nerve injury model. The promising results and the obvious medical need raises hope for a clinical translation of this approach hopefully in the near future.
Assuntos
Nanofibras/química , Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/fisiopatologia , Alicerces Teciduais/química , Animais , Axônios/metabolismo , Movimento Celular , Feminino , Implantes Experimentais , Inflamação/complicações , Inflamação/patologia , Inflamação/fisiopatologia , Atividade Motora , Neurônios Motores/patologia , Músculos/inervação , Músculos/patologia , Músculos/fisiopatologia , Músculos/ultraestrutura , Bainha de Mielina/patologia , Bainha de Mielina/ultraestrutura , Nanofibras/ultraestrutura , Fibras Nervosas/patologia , Fibras Nervosas/ultraestrutura , Tamanho do Órgão , Traumatismos dos Nervos Periféricos/complicações , Traumatismos dos Nervos Periféricos/patologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Células de Schwann/metabolismo , Células de Schwann/patologia , Coloração e RotulagemRESUMO
OBJECTIVE: To quantitatively analyze the temporal and spatial pattern of RhoA expression in injured spinal cord of adult mice. METHODS: A spinal cord transection model was established in adult mice. At 1, 3, 7, 14, 28, 56 and 112 days after the surgery, the spinal cords were dissected and cryosectioned for RhoA/NF200, RhoA/GFAP, RhoA/CNPase or RhoA/IBA1 double fluorescent immunohistochemistry to visualize RhoA expressions in the neurons, astrocytes, oligodendrocytes and microglia. The percentages as well as the immunostaining intensities of RhoA-positive cells in the parenchymal cells were quantitatively analyzed. RESULTS: RhoA was weakly expressed in a few neurons and oligodendrocytes in normal spinal cord. After spinal cord injury, the percentage of RhoA-positive cells and RhoA expression intensity in the spinal cord increased and peaked at 7 days post injury (dpi) in neurons, oligodendrocytes and astrocytes, followed by a gradual decrease till reaching a low level at 112 dpi. In the microglia, both the RhoA-positive cells and RhoA expression intensity reached the maximum at 14 dpi and maintained a high level till 112 dpi. CONCLUSION: Traumatic spinal cord injury can upregulate RhoA expression in the neurons as well as all the glial cells in the spinal cord. RhoA expression patterns vary with post-injury time, location and among different parenchymal cells in the injured spinal cord.