ABSTRACT
Objective:To observe the effect of adipose tissue decellularized matrix hydrogel (DAT-gel) on the repair of sciatic nerve defect in rats.Methods:From April, 2019 to April, 2020, aseptic granular adipose tissue was collected from healthy adult women who underwent thigh or abdominal liposuction in the Department of Plastic Surgery, the First Medical Centre of the PLA General Hospital. Decellularisation and enzymatic digestion of adipose tissue were performed to prepare DAT-gel. Scanning electron microscope (SEM) was used to observe the ultrastructure of the hydrogel, and rheology was employed to test the gel dynamics and viscoelasticity of the hydrogel. A rat model of sciatic nerve defect was established and randomly divided into 3 groups: simple chitin catheter group (Chitin group), DAT-gel plus chitin catheter group (DAT-gel group) and autologous nerve reverse connection group (Autograft group) with 10 rats in each group. At the 12th week after surgery, the general view, function and morphology of the regenerated nerve were observed to evaluate the repairing status of the injured nerve. One-way analysis of variance (one-way ANOVA) was used for data analysis. If the difference between the groups was statistically significant, the Turkey method was further used for pairwise comparison. P<0.05 was considered as statistically significant. Results:The results of SEM showed that the DAT-gel had a three-dimensional structure in porous fibre network. The results of rheological test results showed that the complex viscosity of the hydrogel at 4 ℃ and 37 ℃ were 148.91 mPa·s and 801.29 mPa·s, respectively. DAT-gel underwent a sol-gel phase transition when the temperature had been increased. The results showed that DAT-gel had a good temperature-sensitive effect, and its critical point of sol-gel phase transition was similar to the internal temperature of rat. The results of animal experiments showed that the morphology and function of the regenerated nerve in the DAT-gel group were superior to Chitin group at 12 weeks after surgery, according to macroscopic view of the regenerated nerve, electrophysiology of the nerve, the morphology of the new axon and the target muscle, etc.. There was statistically significant between groups ( P<0.05). Conclusion:DAT-gel can significantly promote a repair of sciatic nerve defects in rats.
ABSTRACT
To investigate the role of the bionic multi-channel nerve conduit by reducing mis-match of regenerated nerve fibers in the rabbit sciatic nerve defect. Methods The experiment was conducted from July, 2017 to February, 2019. A total of 55 New Zealand white rabbits were randomly divided into two groups (First group, n=30 and Second group, n=25).There were 5 subgroups (n=6) in the first group, which were autograft and cus-tom-anatomic nerve conduits (CANC) with different channel (1-CANC, 2-CANC, 3-CANC, 4-CANC) that implanted to repair the rabbit sciatic nerve defect (10 mm). The electrophysiological, triceps muscle wet weight recovery rate, histological study and ankle index analysis were used to evaluate the treatment of each group at 12 and 24 weeks postoperatively. There were 5 subgroups (n=5) in the second group. The simultaneous retrograde tracing method was applied to compare with the number of mismatched nerve fibers at 24 weeks postoperatively. All data were recorded and analyzed by One-way ANOVA method, the Turkey’s method was used to compare the differences between each subgroup. The difference was considered to be statistically significant if P＜0.05. Results The autograft group showed the best recovery in the electrophysiology, histology study and ankle index at 12 and 24 weeks postoperatively (P＜0.05).Histology results showed that the same number of myelinated nerve fibers in all CANC group (P＞0.05), but di-ameters of nerve fiber and myelin thickness were higher in 2-CANC and 3-CANC [(10.67±0.56) μm,(10.65±0.53) μm, respectively] compared with 1-CANC and 4-CANC groups [(8.43±0.63) μm, (9.03±0.55) μm, respectively].The differ-ences were similar in electrophysiological, wet weight recovery rate of triceps muscle, histological study and ankle index analysis.Simultaneous retrograde tracing showed that the autograft group had highest total number of labeled profiles, but no significant difference of the total number of labeled profile was showed among the CANC groups. However, the 1-CANC group[(7.1±2.4) %] showed highest percentage of the FB-NY-neurons than other CANC groups[(2.7±1.9)% in 2-CANC, (2.5±2.3) % in 3-CANC, and (2.2±1.2)% in 4-CANC](P＜0.05). Conclusion The autograft group showed the best results among all groups.Compared with the 1-CANC group, the 2-CANC and 3-CANC group obtained more mature regenerated nerve fibers and with a fewer mismatch rate.Moreover, that did not affect the number of regenerated fibers.