INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua Alfredo Allen 208, Porto, 4200-135, Portugal.
INL- International Iberian Nanotechnology Laboratory, Braga, Portugal.
J Mater Sci Mater Med. 2017 Sep 11;28(10):157. doi: 10.1007/s10856-017-5967-7.
It is now widely accepted that a therapeutic strategy for spinal cord injury (SCI) demands a multi-target approach. Here we propose the use of an easily implantable bilayer polymeric patch based on poly(trimethylene carbonate-co-ε-caprolactone) (P(TMC-CL)) that combines physical guidance cues provided by electrospun aligned fibres and the delivery of ibuprofen, as a mean to reduce the inhibitory environment at the lesion site by taming RhoA activation. Bilayer patches comprised a solvent cast film onto which electrospun aligned fibres have been deposited. Both layers were loaded with ibuprofen. In vitro release (37°C, in phosphate buffered saline) of the drug from the loaded scaffolds under sink condition was found to occur in the first 24 h. The released ibuprofen was shown to retain its bioactivity, as indicated by the reduction of RhoA activation when the neuronal-like cell line ND7/23 was challenged with lysophosphatidic acid. Ibuprofen-loaded P(TMC-CL) bilayer scaffolds were successfully implanted in vivo in a dorsal hemisection rat SCI model mediating the reduction of RhoA activation after 5 days of implantation in comparison to plain P(TMC-CL) scaffolds. Immunohistochemical analysis of the tissue shows βIII tubulin positive cells close to the ibuprofen-loaded patches further supporting the use of this strategy in the context of regeneration after a lesion in the spinal cord.
现在人们普遍认为,脊髓损伤 (SCI) 的治疗策略需要采用多靶点方法。在这里,我们提出使用一种易于植入的双层聚合物贴片,该贴片基于聚(三亚甲基碳酸酯-共聚-ε-己内酯)(P(TMC-CL)),结合了静电纺丝纤维提供的物理导向线索和布洛芬的递送,以通过驯服 RhoA 激活来减少损伤部位的抑制环境。双层贴片由溶剂浇铸膜组成,在该膜上沉积了静电纺丝纤维。两层都加载了布洛芬。在 37°C 下在磷酸盐缓冲盐水中进行的药物体外释放(在溶胀条件下)表明,在最初的 24 小时内,负载支架中的药物释放。负载布洛芬的 P(TMC-CL)双层支架在体内成功植入了背侧半切大鼠 SCI 模型中,与 P(TMC-CL)支架相比,在植入 5 天后可降低 RhoA 激活。与普通 P(TMC-CL)支架相比,植入后 5 天,组织的免疫组织化学分析显示布洛芬负载贴片附近有 βIII 微管蛋白阳性细胞,这进一步支持了在脊髓损伤后再生的背景下使用这种策略。