背景:坐骨神经修复成为神经系统研究的焦点,以恢复动物站立和行走的正常身体能力。组织工程神经移植物(TENGs)为大间隙缺损的再生提供了一种有前途的替代疗法。本研究调查了PRP的再生能力,ADSCs,和PRP混合的ADSCs在通过作为神经支架的聚乙醇聚丙烯(PGA-PRL)网桥接的长坐骨神经缺损(40毫米)上。
方法:该研究对12只成年雄性杂种犬进行,随机分为4组:I组(支架组);其中仅通过(PGA-PRL)网状物桥接坐骨缺损,而在II组(ADSCs组)中,网状物注射ADSCs,第三组PRP(PRP组)。将PRP和ADSCs的混合物分配在组IV(PRP+ADSCs组)中。每月,监测所有动物的步态改善情况,并记录所有组的数字跛行评分.手术后6个月,坐骨神经的结构和功能恢复进行电生理评估,在基因表达水平上,坐骨神经和腓肠肌都进行了形态计量学评估,组织病理学。
结果:数值跛行评分显示,II组和III组的运动活动均有改善,IV组和支架组甚至在6个月后仍有轻度改善。组织病理学,所有治疗组均显示轴突发芽和大量再生束,近端切口有明显的血管生成,和远端部分,其中组IV表现出明显的髓鞘再生MCOOL技术。腓肠肌再生率为23.81%,56.68%,第一组为52.06%和40.69%,II,III和IV;分别。III组和IV组的NGF表达在近端部分均显示出显着的上调(P≤0.0001),而II组则没有显着差异。PDGF-A,和VEGF表达在II组中上调,III,和IV,而I组显示NGF的显着下调,PDGF-A,VEGF(P≤0.0001)。
结论:ADSCs通过分泌几种类型的生长因子,如NGF,对雪旺细胞及其迁移具有增殖作用,在修复受损的神经纤维方面具有重要作用。此外,PRP疗法通过合成另一种生长因子如PDGF-A增强ADSCs的作用,VEGF,NGF用于较好地愈合年夜坐骨间隙缺损。
BACKGROUND: Sciatic nerve repair becomes a focus of research in neurological aspect to restore the normal physical ability of the animal to stand and walk. Tissue engineered nerve grafts (TENGs) provide a promising alternative therapy for regeneration of large gap defects. The present study investigates the regenerative capacity of PRP, ADSCs, and PRP mixed ADSCs on a long sciatic nerve defect (40-mm) bridged by a polyglycolic polypropylene (PGA-PRL) mesh which acts as a neural scaffold.
METHODS: The study was conducted on 12 adult male mongrel dogs that were randomly divided into 4 groups: Group I (scaffold group); where the sciatic defect was bridged by a (PGA-PRL) mesh only while the mesh was injected with ADSCs in Group II (ADSCs group), PRP in Group III (PRP group). Mixture of PRP and ADSCs was allocated in Group IV (PRP + ADSCs group). Monthly, all animals were monitored for improvement in their gait and a numerical lameness score was recorded for all groups. 6 months-post surgery, the structural and functional recovery of sciatic nerve was evaluated electrophysiologically, and on the level of gene expression, and both sciatic nerve and the gastrocnemius muscle were evaluated morphometrically, histopathologically.
RESULTS: Numerical lameness score showed improvement in the motor activities of both Group II and Group III followed by Group IV and the scaffold group showed mild improvement even after 6 months. Histopathologically, all treated groups showed axonal sprouting and numerous regenerated fascicles with obvious angiogenesis in proximal cut, and distal portion where Group IV exhibited a significant remyelination with the MCOOL technique. The regenerative ratio of gastrocnemius muscle was 23.81%, 56.68%, 52.06% and 40.69% for Group I, II, III and IV; respectively. The expression of NGF showed significant up regulation in the proximal portion for both Group III and Group IV (P ≤ 0.0001) while Group II showed no significant difference. PDGF-A, and VEGF expressions were up-regulated in Group II, III, and IV whereas Group I showed significant down-regulation for NGF, PDGF-A, and VEGF (P ≤ 0.0001).
CONCLUSIONS: ADSCs have a great role in restoring the damaged nerve fibers by secreting several types of growth factors like NGF that have a proliferative effect on Schwann cells and their migration. In addition, PRP therapy potentiates the effect of ADSCs by synthesis another growth factors such as PDGF-A, VEGF, NGF for better healing of large sciatic gap defects.