1.Repair of spinal cord injury using Schwann cells in rats: Feasibility and superiority of intravenous transplantation
Hui LI ; Shiqing FENG ; Jiatong CHEN ; Mingyuan HAN ; Chunyuan WANG ; Tieqiang YU
Chinese Journal of Tissue Engineering Research 2010;14(18):3305-3309
BACKGROUND: Emerging studies have focused on cell transplantation. Schwann cells (SCs) can secrete various neurotrophic factors and improve local environment around injury. Plenty of documents have demonstrated that SCs could promote functional recovery following spinal injury. Many transplanting methods are available for treating spinal cord injury, and the intravenous cell transplantation is profitable for easy operation and avoidance of additional trauma. OBJECTIVE: To investigate the effects of intravenous transplantation of SCs on spinal cord injury in rats. METHODS: The bilateral sciatic nerves of Wistar rats were separated in vitro, cultured by tissue clot method, identified by S-100 and labeled by Hoechst33342. Sixty rat models with T10 spinal cord injury were prepared using impactor model- II type weight drop apparatus. Then the injured rats were randomly divided into 3 groups: blank control, DMEM control and SCs transplantation groups. No treatment was performed in the blank control group. Totally 1 mL DMEM and or SCs was injected into rats of DMEM control and SCs transplantation groups by tail vein respectively. Basso Beattie Bresnahan (B6B) scores were performed at 1 day before and 1, 3 days, 1 week and weekly after operation. The migration of transplanted SCs was observed at 2 weeks and 4 after transplantation. The expressions of glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE) were detected by haematoxylin-eosin staining and immune-fluorescence staining.RESULTS AND CONCLUSION: The purity of SCs reached 95%. Hoechst33342 positive cells were observed throughout the injured and the nearby region of spinal cord at 1, 2, and 4 weeks after transplantation. The statistical difference of BBB score among the SCs transplantation, blank control, and the DMEM control groups displayed at 4 weeks after transplantation (P < 0.05), and the BBB scores of the SCs transplantation were higher than other groups. Haematoxylin-eosin staining showed the cavity formed in each group at 8 weeks after transplantation, but the area of SCs transplantation was smaller than that of the blank control and DMEM control groups. The immunofluorescence staining indicated that the expression of GFAP were more intense in the blank control group and DMEM control than SCs transplantation (P < 0.05), while the expression of NSE was more intense in SCs transplantation than other groups (P< 0.05). It implied that intravenous transplantation of SCs promotes regeneration of axon and improves neurological functions after spinal cord injury in rats.
2.Autologous activated Schwann cells transplantation via subarachnoid space for rat spinal cord injury
Chunyuan WANG ; Shiqing FENG ; Yang LIU ; Mingyuan HAN ; Hui LI ; Jiatong CHEN
Chinese Journal of Tissue Engineering Research 2010;14(14):2533-2538
BACKGROUND:Schwann cells can secrete various neurotrophic factors,and promote functional recovery of injured spinal cord.However,xenogenic Schwann cells transplantation may induce autoimmune response.Moreover,local transplantation results in secondary injury.Vein transplantation may reached injury site passing the blood spinal cord barrier,but the treatment concentration is not effective.OBJECTIVE:To investigate the therapeutic effects of transplantation of autologous activated Schwann Cells(AASCs)via subarachnoid space on spinal cord injury(SCI)in rats.METHODS:A total of 66 rats were used to establish SCI models,and the model rats were randomly divided into 3 groups.The unilateral saphenous nerves of rats were ligated directly for 1 week to activate Schwann cells,but inactivated and model control groups were not subjected to nerve ligation.1 cm nerve was excised from distal end of each group,and Schwann cells were isolated and cultured by tissue mass method.The AASCs,autologous Schwann cells(ASCs)were injected with corresponding Hoechst33342-labeted SCs suspension,but the model control group was injected with DMEM injection.The basso beattie bresnahan(BBB)score and footprint analysis,as well as HE and GFAP immunohistochemistry staining were performed to evaluate functional recovery of rat hind limbs.RESULTS AND CONCLUSION:On 4 weeks after injury,BBB scores of AASCs were significantly superior to the other groups (P<0.05).Two weeks after transplantation,some SCs migrated to injured spinal cord.Compared with ASCs group,the center distance of forward and hind feet and extorsion angle of the third toe of hind limb were significantly reduced in the AASCs group at 5 weeks(P<0.05),the glial scar area was significantly decreased at 13 weeks(P<0.05),and the cavity area of injured region was signiflcentJy diminished(P<0.05).Results show that AASCs transplantation via subarachnoid space promoted functional recovery after SCI in rats.
3.Protective effect of n-3 polyunsaturated fatty acids on acute skin photodamage in SKH-1 mice
Yuting XU ; Peiru WANG ; Jiatong HAN ; Xiuli WANG
Chinese Journal of Dermatology 2018;51(8):586-591
Objective To evaluate the protective effect of dietary n-3 polyunsaturated fatty acids (PUFA) on ultraviolet-induced acute skin photodamage in SKH-1 hairless mice,and to explore its mechanism.Methods Totally,50 SKH-1 hairless mice were equally divided into 5 groups to be fed with forages with the ratios of n-3 PUFA to fatty acid being 0,12.5%,25%,50% and 100% respectively (control group,12.5%,25%,50% and 100% n-3 PUFA groups).On day 8 after feeding,the back of mice in the 5 groups were irradiated by a solar ultraviolet simulator at 2 minimum erythema doses (MED) to establish an acute photodamage model.After 24 hours,cutaneous reactions on the back of mice were observed by naked eyes and dermoscopy,and skin biopsy specimens were subjected to hematoxylin and eosin (HE) staining for observing the epidermal structure,intercellular edema,inflammatory cell infiltration and photodamaged cells.Immunohistochemical staining was performed to determine the expression of inflammatory cytokines including interleukin-1 beta (IL-1β),IL-6 and tumor necrosis factor alpha (TNF-α),and enzyme-linked immunosorbent assay (ELISA) to measure the protein expression of the above 3 inflammatory cytokines in the tissue homogenate.Results Compared with the control group and 12.5% n-3 PUFA group,the 25%,50% and 100% n-3 PUFA groups all showed a milder degree of acute skin photodamage,epidermis thickening,intercellular edema,and inflammatory cell infiltration.The number of photodamaged cells per high-power field (× 100) was significantly higher in the control group and 12.5% n-3 PUFA group (17.50 ± 4.93,14.25 ± 1.71,respectively) than in the 25%,50% and 100% n-3 PUFA groups (6.50 ± 1.73,4.75 ± 2.06,4.50 ± 1.73,respectively;F =19.1,P < 0.001).Immunohistochemical results showed that IL-1β,IL-6 and TNF-α were expressed to different extents in the epidermis and dermis among the 5 groups at 24 hours after ultraviolet radiation.Compared with the control group and 12.5% n-3 PUFA group,the 25%,50% and 100% n-3 PUFA groups showed significantly lower expression of the above 3 inflammatory cytokines (P < 0.001).ELISA revealed that the levels of IL-1β,IL-6 and TNF-α in the skin tissues of the mice were significantly lower in the 25%,50% and 100% n-3 PUFA groups than in the control group and 12.5% n-3 PUFA group (P < 0.05).Conclusions When the ratio of n-3 PUFA to fatty acid reaches more than 25%,dietary n-3 PUFA has protective effects against ultraviolet-induced acute photodamage,.Moreover,the higher the content of n-3 PUFA is,the stronger the protective effect is.It is suggested that n-3 PUFA may inhibit the inflammatory reaction through the arachidonic acid pathway.
4.Untargeted and targeted mass spectrometry reveal the effects of theanine on the central and peripheral metabolomics of chronic unpredictable mild stress-induced depression in juvenile rats
Yanru ZHU ; Feng WANG ; Jiatong HAN ; Yunli ZHAO ; Miao YU ; Mingyan MA ; Zhiguo YU
Journal of Pharmaceutical Analysis 2023;13(1):73-87
L-theanine has been shown to have a therapeutic effect on depression.However,whether L-theanine has an excellent preventive effect on depression in children and adolescents and what its mechanism is have not been well explained.Given the complexity of the pathogenesis of depression,this study investigated the preventive effect and mechanism of L-theanine on depression in juvenile rats by combining serum and hippocampal metabolomic strategies.Behavioral tests,hippocampal tissue sections,and serum and hippocampal biochemical indexes were studied,and the results confirmed the preventive effect of L-theanine.Untargeted reversed-phase liquid chromatography-quadrupole-time-of-flight mass spec-trometry and targeted hydrophilic interaction liquid chromatography-triple quadrupole mass spec-trometry were developed to analyze the metabolism changes in the serum and hippocampus to screen for potential biomarkers related to L-theanine treatment.The results suggested that 28 abnormal me-tabolites in the serum and hippocampus that were considered as potential biomarkers returned to near-normal levels after L-theanine administration.These biomarkers were involved in various metabolic pathways,mainly including amino acid metabolism and lipid metabolism.The levels of amino acids and neurotransmitters in the phenylalanine,tryptophan,and glutamic acid pathways were significantly reduced after L-theanine administration compared with chronic unpredictable mild stress-induced rats.In summary,L-theanine had a significant preventive effect on depression and achieved its preventive results on depression by regulating various aspects of the body,such as amino acids,lipids,and inflammation.This research systematically analyzed the mechanism of L-theanine in preventing depression and laid the foundation for applying L-theanine to prevent depression in children and adolescents.
5.HYD-PEP06 suppresses hepatocellular carcinoma metastasis, epithelial-mesenchymal transition and cancer stem cell-like properties by inhibiting PI3K/AKT and WNT/
Wei TIAN ; Jiatong LI ; Zhuo WANG ; Tong ZHANG ; Ying HAN ; Yanyan LIU ; Wenfeng CHU ; Yu LIU ; Baofeng YANG
Acta Pharmaceutica Sinica B 2021;11(6):1592-1606
HYD-PEP06, an endostatin-modified polypeptide, has been shown to produce effective anti-colorectal carcinoma effects through inhibiting epithelial-mesenchymal transition (EMT). However, whether HYD-PEP06 has similar suppressive effect on hepatocellular carcinoma (HCC) remained unknown. In this study, HYD-PEP06 inhibited metastasis and EMT but not proliferation