Schwanns cells were obtained from the distal end of the sciatic nerve following Wallerian degeneration of SD rats. These cells were cultured with the anteriorhorn neuron of spinal cord of 14dayold SD rat fetus. The two kinds of cells were separated by a slice. Through the microscope, the dendrites and the morphology changes at the 24th, 48th, 72th, and 96 th hour after culture were observed. It was demonstrated that the Schwanns cells played the role of maintaining the survival of neuron and promoting the growth of dendrites. It was said that the Schwanns cells could secrete neurotrophic factor which made the body enlarged and caused the dendrites enlonged to several times of the body.
In order to observe the role of genetically modified Schwann cell (SC) with pSVP0Mcat in the regeneration of injured spinal cord, the cells were implanted into the spinal cord. Ninety SD rats were used to establish a model of hemi-transection of spinal cord at the level of T8, and were divided into three groups, randomly, that is, pSVP0Mcat modified SC implantation (Group A), SC implantation (Group B) and without cell implantation as control (Group C). After three months the presence of axonal regeneration of the injured spinal cord was examined by means of horseradish peroxidase (HRP) retrograde labelling technique and stereography. The results indicated that HRP labelled cells in Group A and B could be found in the superior region of injured spinal cord and the brain stem such as the red nuclei and oculomotor nuclei. The density of ventral hom neurons of the spinal cord and the number of myelinated axons in 100 microns of the white matter was A gt; B gt; C group. In brief, the pSVP0Mcat modified SC intraspinal implantation could promote regeneration of the injured spinal cord.
Basing on the experimental results, 48 nerve defects (with the length of 3-4 cm in 21 cases, 4.1-5cm in 25 cases and 6cm in 2 cases) were repaired clinically by using vaseularized nerve sheath canal with living Schwann s cells, 87.5 percent of them obtained good results. The advantages were: (1) The neural sheath had rich blood supply with resultant less scar from its healing; (2) The living Schwann s cells would secrete somatomedin to promote the reproduction of neural tissues; and (3) The useless neurofib...
Abstract: The amniotic fluidderived stem cells (AFSC) possess considerable advantageous characteristics including high proliferation potential, easy availability, low immunogenicity and oncogenicity，and accordance with medical ethnics. Moreover, they do not require the sacrifice of human embryos for their isolation and the cells can differentiate into all three kinds of germs. Accordingly，they initiate a new and very promising field in stem cell research and they will be a potential source of stem cells for therapies related to regeneration medicine of cardiovascular diseases. The research about the AFSC utilization in cardiovascular diseases is just started. Though there were some exciting breakthroughs, there still remain many challenges. In the article，we will discuss AFSC characteristics, influence of amniotic fluid harvesting time on stem cells, isolation and purification, emphasizing mainly on the potential of AFSC differentiation into cardiovascular cells, current situation and problems in this field.
Objective To review researches of the role of inhibitorof differentiation 2(Id2) in skeletal muscle regeneration. Methods The latest original literature concerning Id2 and its role in skeletal muscle regeneration was extensively reviewed. Results Id2 could form heterodimers by combining with E protein to prevent myogenic regulatory factors (MRFs) forming heterodimers by combining with E protein, to inhibit the transcription activity of MRFs anddifferentiation of skeletal muscle cell. Conclusion Id2 plays an important role in skeletal muscle regeneration.
Schwanns cell (SC) was isolated from sciatic nerve of adult rat with Wallerine degeneration. After culture, SC-serum free culture media (SCSFCM) was obtained. By ultrafiltration with PM-10 Amicon Membrane, electrophoresis with DiscPAGE,and electrical wash-out with Biotrap apparatus, D-band protein was isolated from the SC-SFCM. The D-band protein in the concentration of 25ng/ml could affect the survival of the spinal anterior horn neuron in vitro, prominently and itsactivity was not changed after being frozen. The molecular weight of the protein ranged from 43 to 67 Kd. The D-band protein might be a neurotrophic substancedifferent from the known SCderived neurotrophic factors (NTF). Its concentration with biological activity was high enough to be detected. The advantages of MTT in assessment of NTF activity were also discussed.
Objective To investigate the outcome of repairing the peripheral nerve defects with the tissue engineered nerve constructed by Schwann cells and fibrin glue. Methods Wallerian degenerated sciatic nerve were harvested from the 4-week-old New Zealand rabbits for culture of Schwann cells. The Schwann cells were then separated, amplified and purified, and then were identified by the S-100 protein immunochemical staining. The cultured Schwann cells (1×106/ml) were mixed with fibrin glue to form the Schwann cell-fibrin glue compound, which was observed by the inverted phase contrastmicroscope. The compound filled some silicone tubes (Group A) and biomembrane (Group B) to fabricate the tissue engineered nerves with a purpose of repairing the 10-mm defects in the New Zealand rabbit tibia nerves. The autologous nerve grafting was performed in Group C. The electrophysiological examination and the histomorphological analysis were performed at 10 weeks after the transplantation. Results All the rabbits survived through the experiment. In Group A, all the rabbits developed an ulcer in the soles of their left feet at 3-4weeks after the transplantation, while less ulceration developed in Groups B and C. At 10 weeks after the transplantation, the electrophysiological examination was performed, the elective stimulation failed to pass through the nerve grafts, and no composed muscular action potential was found in all the rabbits in Group A; the elective stimulation could pass through all the nerve grafts in Groups B and C, and could evoke the composed muscular action potential; the composed muscular action potential and the nerve conduct velocity in the two groups were 4.21±0.82 mV and 3.40±5.40 m/s vs. 4.80±1.15 mV and 36.55±6.43 m/s(Pgt;0.05). In Group A, no regrown axon was found in the nerve grafts, but neuromawas found to have formed in the both ends of the silicon tube. In Groups B and C, there was no obvious neuroma formation but regrown axons could be found to have regenerated. The histomorphological analysis on the regrown axons showed thatthere was no statistically significant difference between Groups B and C. Conclusion The tissue engineered nerve fabricated with Schwann cells, fibrin glue, and biomembrane can promote the nerve regeneration, and its reparative effect is similar to that of the autologous nerves; therefore, the future of its clinical practice is brilliant.
Objective To investigate the velvet antler polypeptide (VAP) on sciatic nerve regeneration in rats through local administration and VAP-PLGA compound membrane. Methods The 3, 15 mg/g of VAP-PLGA compound membranewere prepared by compounding VAP and PLGA, respectively. Seventy-two Wistar rats, male or female, aged 3-6 months and weighing (250 ± 50) g, were selected to make the model of sciatic nerve section. Then, all rats were randomized into 4 groups (n=18): group A in which nothing was given after anatomosis, group B in which 1 mL of VAP at the concentration of 10 mg/L was injected into the gastrocnemius muscle medial for every other day, group C in which 3 mg/g of VAP-PLGA compound membrane was given to the nerve anastomotic stoma and group D in which 15 mg/g of VAP-PLGA compound membrane was given to the nerve anastomotic stoma. The sciatic adhesion degree observation, electrophysiological examination, immunohistochemical staining and hemi-quantity calculation and horseradish peroxidase (HRP) retrograde tracing were conducted 2, 4 and 6 weeks after operation, respectively. Results All rats survived to the end of the experiment, without foot ulcer or neuroma. Severer nervous adherence was observed in group A, mild adherence in group B, and no adherence in groups C and D 2, 4 and 6 weeks after operation, respectively. The recovery rate of the evoked potential of triceps surae in groups B, C and D was better than that in group A (P lt; 0.01), group D was superior to groups B and C (P lt; 0.05) at each time point. No significant difference between group B and group C (P gt; 0.05) 2, 4 weeks after operation was detected, but group C was superior to group B (P lt; 0.05) 6 weeksafter operation. For the regenerative fiber axon and the expression of myelin sheath TGF-β1 and IGF antigen, the staining intensity in groups B, C and D was higher than that in group A at each time point (P lt; 0.05), and there were significant differences between group D and groups B and C 6 weeks after operation (P lt; 0.05), but no difference between groups B and C (P gt; 0.05). The HRP retrograde tracing showed that the myelinated nerve fiber stained by HRP gradually increased as time passed by and myelinated nerve fiber stained by HRP in groups B, C and D was much more than that in group A, and group D was superior to the other groups. No significant difference between group B and group C was detected. Conclusion To apply VAP through either local administration or VAP-PLGA compound membrane around the attached site of nerve anastomosis is capable of promoting nerve regeneration, which has an obvious dose-effect relationship with the dose of VAP. Meanwhile, VAP-PLGA compound membrane can prevent the nerve adhesion.
OBJECTIVE: To review the role of thyroid hormone in the peripheral nerve regeneration. METHODS: The recent literatures of experimental study and clinical application on the role of thyroid hormone in nerve regeneration were reviewed. The researches on expression, isoform and changes of thyroid hormones in rat sciatic nerve in normal or injury were summarized. The effect of thyroid hormone on local rat sciatic nerve was studied, too. RESULTS: Nuclear thyroid hormone receptors expressed in numerous nuclei of sciatic nerve during a limited period of development extending from the third week of embryonic life to the end of the second postnatal week and after injury of adult sciatic nerve. A single and local administration of thyroid hormone at the level of the transected sciatic nerve produced a lasting effect on peripheral nerve regeneration. CONCLUSION: The beneficial effects of thyroid hormones upon injured peripheral nerve may have considerable therapeutic potential.
The capacity for self-regeneration of the adult heart is very limited, conventional therapies cannot solve the loss of cardiomyocytes in the infarcted heart leads to continuous ventricular remodeling. Cell transplantation therapy is emerging as a novel approach for myocardial repair over conventional therapies. Various types of cell transplantation have improved cardiac function and angiogenesis in animal models and clinical settings. The safety and feasibility of some clinical trials have been initiated. In this review, we summarize the advantages and limitations of different cell types proposed for cell transplantation in myocardial infarction and give an overview of the clinical trials using this novel therapeutic approach in patients with myocardial infarction.