Rezende Alexandre C, Peroni Daniele, Vieira Andrè S, Rogerio Fabio, Talaisys Rafael L, Costa Fabio T M, Langone Francesco, Skaper Stephen D, Negro Alessandro
Department of Physiology and Biophysics, State University of Campinas, Campinas, Brazil.
J Neurochem. 2009 Jun;109(6):1680-90. doi: 10.1111/j.1471-4159.2009.06091.x. Epub 2009 Apr 7.
Ciliary neurotrophic factor (CNTF) is a multifunctional cytokine that can regulate the survival and differentiation of many types of developing and adult neurons. CNTF prevents the degeneration of motor neurons after axotomy and in mouse mutant progressive motor neuronopathy, which has encouraged trials of CNTF for human motor neuron disease. Given systemically, however, CNTF causes severe side effects, including cachexia and a marked immune response, which has limited its clinical application. The present work describes a novel approach for administering recombinant human CNTF (rhCNTF) while conserving neurotrophic activity and avoiding deleterious side effects. rhCNTF was fused to a protein transduction domain derived from the human immunodeficiency virus-1 TAT (transactivator) protein. The resulting fusion protein (TAT-CNTF) crosses the plasma membrane within minutes and displays a nuclear localization. TAT-CNTF was equipotent to rhCNTF in supporting the survival of cultured chicken embryo dorsal root ganglion neurons. Local or subcutaneous administration of TAT-CNTF, like rhCNTF rescued motor neurons from death in neonatal rats subjected to sciatic nerve transection. In contrast to subcutaneous rhCNTF, which caused a 20-30% decrease in body weight in neonatal rats between postnatal days 2 and 7 together with a considerable fat mobilization in brown adipose tissue, TAT-CNTF lacked such side effects. Together, these results indicate that rhCNTF fused with the protein transduction domain/TAT retains neurotrophic activity in the absence of CNTFs cytokine-like side effects and may be a promising candidate for the treatment of motor neuron and other neurodegenerative diseases.
睫状神经营养因子（CNTF）是一种多功能细胞因子，可调节多种发育中和成年神经元的存活与分化。CNTF可防止轴突切断后运动神经元的退化，以及小鼠突变型进行性运动神经元病中的神经元退化，这促使人们对CNTF用于人类运动神经元疾病进行试验。然而，全身性给予CNTF会导致严重的副作用，包括恶病质和明显的免疫反应，这限制了其临床应用。本研究描述了一种新型的重组人CNTF（rhCNTF）给药方法，既能保留神经营养活性，又能避免有害的副作用。rhCNTF与源自人类免疫缺陷病毒1型TAT（反式激活因子）蛋白的蛋白转导结构域融合。所得融合蛋白（TAT-CNTF）在数分钟内穿过质膜，并显示出核定位。在支持培养的鸡胚背根神经节神经元存活方面，TAT-CNTF与rhCNTF具有同等效力。与rhCNTF一样，局部或皮下给予TAT-CNTF可挽救坐骨神经横断新生大鼠的运动神经元免于死亡。皮下注射rhCNTF会导致出生后2至7天的新生大鼠体重下降20%-30%，同时棕色脂肪组织中有大量脂肪动员，而TAT-CNTF则没有此类副作用。总之，这些结果表明，与蛋白转导结构域/TAT融合的rhCNTF在没有CNTF细胞因子样副作用的情况下保留了神经营养活性，可能是治疗运动神经元和其他神经退行性疾病的有前景的候选药物。
