Adipose tissue-deried stem cells( ADSCs) are adult stem cells that can be easily harvested from subcutaneous adipose tissue. Many studies have demonstrated that ADSCs differentiate into vascular endothelial cells(VECs...Adipose tissue-deried stem cells( ADSCs) are adult stem cells that can be easily harvested from subcutaneous adipose tissue. Many studies have demonstrated that ADSCs differentiate into vascular endothelial cells(VECs), vascular smooth muscle cells(VSMCs), and cardiomyocytes in vitro and in vivo. However, ADSCs may fuse with tissue-resident cells and obtain the corresponding characteristics of those cells. If fusion occurs, ADSCs may express markers of VECs, VSMCs, and cardiomyocytes without direct differentiation into these cell types. ADSCs also produce a variety of paracrine factors such as vascular endothelial growth factor, hepatocyte growth factor, and insulin-like growth factor-1 that have proangiogenic and/or antiapoptotic activities. Thus, ADSCs have the potential to regenerate the cardiovascular system via direct differentiation into VECs, VSMCs, and cardiomyocytes, fusion with tissueresident cells, and the production of paracrine factors. Numerous animal studies have demonstrated the efficacy of ADSC implantation in the treatment of acute myocardial infarction(AMI), ischemic cardiomyopathy(ICM), dilated cardiomyopathy, hindlimb ischemia, and stroke. Clinical studies regarding the use of autologous ADSCs for treating patients with AMI and ICM have recently been initiated. ADSC implantation has been reported as safe and effective so far. Therefore, ADSCs appear to be useful for the treatment of cardiovascular disease. However, the tumorigenic potential of ADSCs requires careful evaluation before their safe clinical application.展开更多
Objective:To investigate the effect and mechanism of Xuefu Zhuyu Capsule(血府逐瘀胶囊,XZC)on pro-angiogenesis in the hindlimb ischemic model rats.Methods:A total of 100 Sprague Dawley rats were randomly divided into a...Objective:To investigate the effect and mechanism of Xuefu Zhuyu Capsule(血府逐瘀胶囊,XZC)on pro-angiogenesis in the hindlimb ischemic model rats.Methods:A total of 100 Sprague Dawley rats were randomly divided into a model group,a regular-dose XZC group(0.48 g·kg^-1·d^-1)and a high-dose XZC group(0.96 g·kg^-1·d^-1)using random number table method.The model of hindlimb ischemic rats were made through femoral artery embolization with Bletilla microsphere age nt.XZC were give n on the first day after embolization surgery and lasted 5 days.Finally 72 models were obtained with 12 in each group for each time point.The lower Ischemic limb was amputated on the third day after embolization surgery.Histopathological characters and the number of blood vessels of granulation tissues were observed at 36 and 48 h after amputation,respectively.The main genes were obtained from microarray analysis and were validated using real-time quarttitative polymerase chain reaction.Results:The vascular number of granulation tissues at both 36 and 48 h were characterized by new and fresh vessels.The number of angiogenesis in the high-dose XZC group at 36 and 48 h was greater compared with that in the regular-dose XZC and model groups(P<0.01),and high-dose XZC at 36 h increased more vessels than that at 48 h(P<0.01).Consequently,granulation tissues from the high-dose XZC group at 36 h were chosen for microarray analysis.In all,2,085 differentially expressed genes(DEGs)were detected and 25 DEGs were determined to be directly related to an giogenesis.Four biological process terms were found including an giogenesis,regulati on of an gioge nesis,positive regulati on of an giogenesis,and positive regulation of vascular end othelial growth factor receptor sign aling pathway(P<0.05).Microarray an alysis also showed 49 pathways including 11 pathways related to an giogenesis.Conclusion:XZC promoted angiogenesis moderately and the mechanism invoIved multiple DEGs and multiple pathways.展开更多
目的:观察母体的肢体缺血预处理(LIP)对宫内窘迫胎鼠复氧后海马神经元凋亡的影响。方法:采用微动脉夹阻断母鼠通向子宫和卵巢的动静脉15 min后开放以制备胎鼠宫内窘迫模型。孕19 d SD大鼠12只,随机分为4组:空白对照(S)组、LIP组、胎儿窘...目的:观察母体的肢体缺血预处理(LIP)对宫内窘迫胎鼠复氧后海马神经元凋亡的影响。方法:采用微动脉夹阻断母鼠通向子宫和卵巢的动静脉15 min后开放以制备胎鼠宫内窘迫模型。孕19 d SD大鼠12只,随机分为4组:空白对照(S)组、LIP组、胎儿窘迫(FD)组和LIP+FD组。各组母鼠再灌注2 d时剖宫取活胎鼠12只断头取脑。TUNEL法测定胎鼠海马CA1区神经元凋亡情况,计算细胞凋亡指数;免疫组化法和Western blotting法测定Bcl-2和Bax蛋白的表达。结果:与S组比较,FD组和LIP+FD组胎鼠海马CA1区神经元凋亡指数增加(P<0.05),Bcl-2蛋白表达增加,Bax蛋白表达增加,Bcl-2/Bax比值降低;与S组比较,LIP组胎鼠海马CA1的Bcl-2、Bax蛋白表达及Bcl-2/Bax蛋白表达的比值无明显改变(P>0.05);与FD组比较,LIP+FD组细胞凋亡指数降低(P<0.05),Bcl-2/Bax比值增加。结论:母体肢体缺血预处理减轻了宫内窘迫胎鼠复氧后海马神经元的凋亡,其机制可能与Bcl-2蛋白表达的上调相关。展开更多
In chronic phase of spinal cord injury, functional recovery is more untreatable compared with early intervention in acute phase of spinal cord injury. In the last decade, several combination therapies successfully imp...In chronic phase of spinal cord injury, functional recovery is more untreatable compared with early intervention in acute phase of spinal cord injury. In the last decade, several combination therapies successfully improved motor dysfunction in chronic spinal cord injury. However, their effectiveness is not sufficient. We previously found a new effective compound for spinal cord injury, matrine, which induced axonal growth and functional recovery in acute spinal cord injury mice via direct activation of extracellular heat shock protein 90. Although our previous study clarified that matrine was an activator of extracellular heat shock protein 90, the potential of matrine for spinal cord injury in chronic phase has not been sufficiently evaluated. Thus, this study aimed to investigate whether matrine ameliorates chronic spinal cord injury in mice. Once daily intragastric administration of matrine(100 μmol/kg per day) to spinal cord injury mice were starte at 28 days after injury, and continued for 154 days. Continuous mat rine treatment improved hindlimb motor function in chronic spinal cord injury mice. In injured spinal cords of the matrine-treated mice, the density of neurofilament-H-positive axons was increased. Moreover, matrine treatment increased the density of bassoon-positive presynapses in contact with choline acetyltransferase-positive motor neurons in the lumbar spinal cord. These findings suggest that matrine promotes remodeling and reconnection of neural circuits to regulate hindlimb movement. All protocols were approved by the Committee for Animal Care and Use of the Sugitani Campus of the University of Toyama(approval No. A2013 INM-1 and A2016 INM-3) on May 7, 2013 and May 17, 2016, respectively.展开更多
Spinal cord injury is associated with chronic sensorimotor deficits due to the interruption of ascending and descending tracts between the brain and spinal cord. Functional recovery after anatomically complete spinal ...Spinal cord injury is associated with chronic sensorimotor deficits due to the interruption of ascending and descending tracts between the brain and spinal cord. Functional recovery after anatomically complete spinal cord injury is limited due to the lack of long-distance axonal regeneration of severed fibers in the adult central nervous system. Most spinal cord injuries in humans, however, are anatomically incomplete. Although restorative treatment options for spinal cord injury remain currently limited, research from experimental models of spinal cord injury have revealed a tremendous capability for both spontaneous and treatment-induced plasticity of the corticospinal system that supports functional recovery. We review recent advances in the understanding of corticospinal circuit plasticity after spinal cord injury and concentrate mainly on the hindlimb motor cortex, its corticospinal projections, and the role of spinal mechanisms that support locomotor recovery. First, we discuss plasticity that occurs at the level of motor cortex and the reorganization of cortical movement representations. Next, we explore downstream plasticity in corticospinal projections. We then review the role of spinal mechanisms in locomotor recovery. We conclude with a perspective on harnessing neuroplasticity with therapeutic interventions to promote functional recovery.展开更多
目的:NOD样受体热蛋白结构域相关蛋白6(NOD-like receptor thermal protein domain associated protein 6,NLRP6)是新发现的寡聚化核苷酸结合结构域样受体家族成员,广泛表达于肠道、肝脏、肾脏、脾脏和肌肉等组织器官,在炎症、焦亡和自...目的:NOD样受体热蛋白结构域相关蛋白6(NOD-like receptor thermal protein domain associated protein 6,NLRP6)是新发现的寡聚化核苷酸结合结构域样受体家族成员,广泛表达于肠道、肝脏、肾脏、脾脏和肌肉等组织器官,在炎症、焦亡和自噬等多种生物过程发挥广泛的调节作用。近期研究表明,NLRP6在应激条件下对多种组织器官的疾病表型具有重要影响。然而,NLRP6对组织器官生长发育的影响尚未可知。方法:采用CRISPR/Cas9基因编辑技术构建NLRP6基因敲除小鼠,饲养并记录小鼠的生长和繁殖情况。将小鼠的脾、肝、心、肾、脑、四肢和后背皮肤等组织器官进行解剖和切片染色,以评估NLRP6基因敲除对实质器官的宏观发育影响和对组织结构的微观影响。结果:在自然状态下,NLRP6基因敲除缩短了雄鼠的性成熟期并使成年雄鼠的睾丸发生不可逆的破溃与萎缩。在四肢发育上,NLRP6基因敲除诱导成年雄鼠后肢横纹肌断裂,导致后肢明显萎缩。在脾脏发育上,NLRP6基因敲除不仅显著增加了雄鼠的脾脏体积(P<0.01)还诱导雄鼠脾脏出现炎性细胞浸润。在后背皮肤上,NLRP6基因敲除引发雄鼠后背皮肤出现明显的溃疡损伤、胶原纤维增生和炎性细胞浸润。结论:在自然生长发育条件下,NLRP6基因敲除选择性影响小鼠的生殖器发育与性成熟期、后肢肌肉发育、脾脏大小及其炎症免疫状态以及后背皮肤的结构完整性,而且这一作用具有明显的雄激素依赖性。展开更多
The endochondral ossification of hindlimb is essential to a bird’s ability to stand,walk and fly.Most hindlimb is ossified in the embryos before hatching in precocial birds.However,the molecular mechanisms of hindlim...The endochondral ossification of hindlimb is essential to a bird’s ability to stand,walk and fly.Most hindlimb is ossified in the embryos before hatching in precocial birds.However,the molecular mechanisms of hindlimb ossification in birds is still unclear.Therefore,we tried to examine the process of hindlimb ossification and its molecular regulation by using an animal model—Japanese Quail(Coturnix japonica).We selected four critical stages(Embryo Day:E6,E8,E12 and E16) of skeletal development of embryonic quails for hindlimb skeleton staining to show the process of endochondral ossification and to examine the molecular regulation of endochondral osteogenesis by RNA-Seq analysis.The results showed that ossification became increased with embryonic development and most hindlimb was ossified before hatching.RNA-Seq analysis revealed that various signaling pathways were involved with endochondral ossification with thyroid hormone signaling and WNT signaling pathway particularly enriched.Moreover,the expression levels of 42 genes were continuously upregulated and 14 genes were continuously downregulated from E6 to E16.The present study might provide new insights into complex molecular mechanisms in regulation of endochondral ossification.展开更多
AIM To evaluate the angiogenic effect of platelet-rich plasma(PRP)-preconditioned adipose-derived stem cells(ADSCs) both in vitro and in a mouse ischemic hindlimb model.METHODS ADSCs were divided based on culture medi...AIM To evaluate the angiogenic effect of platelet-rich plasma(PRP)-preconditioned adipose-derived stem cells(ADSCs) both in vitro and in a mouse ischemic hindlimb model.METHODS ADSCs were divided based on culture medium: 2.5% PRP, 5% PRP, 7.5% PRP, and 10% PRP. Cell proliferation rate was analyzed using the MTS assay. The gene expression of CD31, vascular endothelial growth factor, hypoxia-inducible factors, and endothelial cell nitric oxide synthase was analyzed using reverse transcription polymerase chain reaction. Cell markers and structural changes were assessed through immunofluorescence staining and the tube formation assay. Subsequently, we studied the in vivo angiogenic capabilities of ADSCs by a mouse ischemic hindlimb model.RESULTS The proliferation rate of ADSCs was higher in the 2.5%, 5%, and 7.5% PRP groups. The expression of hypoxia-inducible factor, CD31, vascular endothelial growth factor, and endothelial cell nitric oxide synthase in the 5% and 7.5% PRP groups increased. The 5%, 7.5%, and 10% PRP groups showed higher abilities to promote both CD31 and vascular endothelial growth factor production and tubular structure formation in ADSCs. According to laser Doppler perfusion scan, the perfusion ratios of ischemic limb to normal limb were significantly higher in 5% PRP, 7.5% PRP, and human umbilical vein endothelial cells groups compared with the negative control and fetal bovine serum(FBS) groups(0.88 ± 0.08, 0.85 ± 0.07 and 0.81 ± 0.06 for 5%, 7.5% PRP and human umbilical vein endothelial cells compared with 0.42 ± 0.17 and 0.54 ± 0.14 for the negative control and FBS, P < 0.01).CONCLUSION PRP-preconditioned ADSCs presented endothelial cell characteristics in vitro and significantly improved neovascularization in ischemic hindlimbs. The optimal angiogenic effect occurred in 5% PRP-and 7.5% PRPpreconditioned ADSCs.展开更多
Non-traumatic injury accounts for approximately half of clinical spinal cord injury, including chronic spinal cord compression. However, previous rodent spinal cord compression models are mainly designed for rats, few...Non-traumatic injury accounts for approximately half of clinical spinal cord injury, including chronic spinal cord compression. However, previous rodent spinal cord compression models are mainly designed for rats, few are available for mice. Our aim is to develop a thoracic progressive compression mice model of spinal cord injury. In this study, adult wild-type C57BL/6 mice were divided into two groups： in the surgery group, a screw was inserted at T9 lamina to compress the spinal cord, and the compression was increased by turning it further into the canal（0.2 mm） post-surgery every 2 weeks up to 8 weeks. In the control group, a hole was drilled into the lamina without inserting a screw. The results showed that Basso Mouse Scale scores were lower and gait worsened. In addition, the degree of hindlimb dysfunction in mice was consistent with the degree of spinal cord compression. The number of motor neurons in the anterior horn of the spinal cord was reduced in all groups of mice, whereas astrocytes and microglia were gradually activated and proliferated. In conclusion, this progressive compression of thoracic spinal cord injury in mice is a preferable model for chronic progressive spinal cord compression injury.展开更多
Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used an...Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used and clinically relevant thoracic contusion/compression spinal cord injury model in rats. Rats were randomly assigned to either a T9 spinal cord injury or sham laminectomy. Locomotion recovery was assessed using the Basso, Beattie, and Bresnahan open field rating scale and the CatWalk XT■gait analysis. To determine the potential bias from weight changes, corrected hindlimb(H) values(divided by the unaffected forelimb(F) values) were calculated. Six weeks after injury, cyst formation, astrogliosis, and the deposition of chondroitin sulfate glycosaminoglycans were assessed by immunohistochemistry staining. Compared with the baseline, a significant spontaneous recovery could be observed in the CatWalk XT■parameters max intensity, mean intensity, max intensity at%, and max contact mean intensity from 4 weeks after injury onwards. Of note, corrected values(H/F) of CatWalk XT■parameters showed a significantly less vulnerability to the weight changes than absolute values, specifically in static parameters. The corrected CatWalk XT■parameters were positively correlated with the Basso, Beattie, and Bresnahan rating scale scores, cyst formation, the immunointensity of astrogliosis and chondroitin sulfate glycosaminoglycan deposition. The CatWalk XT■gait analysis and especially its static parameters, therefore, seem to be highly useful in assessing spontaneous recovery of hindlimb function after severe thoracic spinal cord injury. Because many CatWalk XT■parameters of the hindlimbs seem to be affected by body weight changes, using their corrected values might be a valuable option to improve this dependency.展开更多
Muscle necrosis and angiogenesis are two major challenges in the treatment of lower-limb ischemic diseases.In this study,a triple-functional Sr/Si-containing bioceramic/alginate composite hydrogel with simultaneous bi...Muscle necrosis and angiogenesis are two major challenges in the treatment of lower-limb ischemic diseases.In this study,a triple-functional Sr/Si-containing bioceramic/alginate composite hydrogel with simultaneous bioactivity in enhancing angiogenesis,regulating inflammation,and inhibiting muscle necrosis was designed to treat lower-limb ischemic diseases.In particular,sodium alginate,calcium silicate and strontium carbonate were used to prepare injectable hydrogels,which was gelled within 10 min.More importantly,this composite hydrogel sustainedly releases bioactive Sr^(2+)and SiO_(3)^(2-) ions within 28 days.The biological activity of the bioactive ions released from the hydrogels was verified on HUVECs,SMCs,C2C12 and Raw 264.7 cells in vitro,and the therapeutic effect of the hydrogel was confirmed using C57BL/6 mouse model of femoral artery ligation in vivo.The results showed that the composite hydrogel stimulated angiogenesis,developed new collateral capillaries,and re-established the blood supply.In addition,the bioactive hydrogel directly promoted the expression of muscle-regulating factors(MyoG and MyoD)to protect skeletal muscle from necrosis,inhibited M1 polarization,and promoted M2 polarization of macrophages to reduce inflammation,thereby protecting skeletal muscle cells and indirectly promoting vascularization.Our results indicate that these bioceramic/alginate composite bioactive hydrogels are effective biomaterials for treating hindlimb ischemia and suggest that biomaterial-based approaches may have remarkable potential in treating ischemic diseases.展开更多
In many anurans, the forelimb muscles of males are used to grasp females and are often heavier than those of females despite the larger female body size. Such sexual dimorphism in forelimb musculature is thought to re...In many anurans, the forelimb muscles of males are used to grasp females and are often heavier than those of females despite the larger female body size. Such sexual dimorphism in forelimb musculature is thought to result from sexual selection. In addition, the hindlimbs of frogs and toads play an important role in the reproductive process as amplectant males can expel rivals with robust hindlimbs through kicking. In this study, the sexual dimorphism in dry mass for six hindlimb muscles of the Asiatic toad （Bufo gargarizans） was investigated. The results showed that, when controlled for body size, the hindlimb muscle mass of males significantly exceeded that of females for every muscle. The hindlimb muscle mass of amplectant males was also significantly larger than that of non-amplectant males. These results suggested that if strong hindlimb muscles could improve mating success of males, sexual selection would promote the evolution of dimorphism in this character.展开更多
文摘Adipose tissue-deried stem cells( ADSCs) are adult stem cells that can be easily harvested from subcutaneous adipose tissue. Many studies have demonstrated that ADSCs differentiate into vascular endothelial cells(VECs), vascular smooth muscle cells(VSMCs), and cardiomyocytes in vitro and in vivo. However, ADSCs may fuse with tissue-resident cells and obtain the corresponding characteristics of those cells. If fusion occurs, ADSCs may express markers of VECs, VSMCs, and cardiomyocytes without direct differentiation into these cell types. ADSCs also produce a variety of paracrine factors such as vascular endothelial growth factor, hepatocyte growth factor, and insulin-like growth factor-1 that have proangiogenic and/or antiapoptotic activities. Thus, ADSCs have the potential to regenerate the cardiovascular system via direct differentiation into VECs, VSMCs, and cardiomyocytes, fusion with tissueresident cells, and the production of paracrine factors. Numerous animal studies have demonstrated the efficacy of ADSC implantation in the treatment of acute myocardial infarction(AMI), ischemic cardiomyopathy(ICM), dilated cardiomyopathy, hindlimb ischemia, and stroke. Clinical studies regarding the use of autologous ADSCs for treating patients with AMI and ICM have recently been initiated. ADSC implantation has been reported as safe and effective so far. Therefore, ADSCs appear to be useful for the treatment of cardiovascular disease. However, the tumorigenic potential of ADSCs requires careful evaluation before their safe clinical application.
基金Supported by the National Natural Science Foundation of China(No.81072933,81173431)the Beijing Natural Science Foundation Program(No.7122120)
文摘Objective:To investigate the effect and mechanism of Xuefu Zhuyu Capsule(血府逐瘀胶囊,XZC)on pro-angiogenesis in the hindlimb ischemic model rats.Methods:A total of 100 Sprague Dawley rats were randomly divided into a model group,a regular-dose XZC group(0.48 g·kg^-1·d^-1)and a high-dose XZC group(0.96 g·kg^-1·d^-1)using random number table method.The model of hindlimb ischemic rats were made through femoral artery embolization with Bletilla microsphere age nt.XZC were give n on the first day after embolization surgery and lasted 5 days.Finally 72 models were obtained with 12 in each group for each time point.The lower Ischemic limb was amputated on the third day after embolization surgery.Histopathological characters and the number of blood vessels of granulation tissues were observed at 36 and 48 h after amputation,respectively.The main genes were obtained from microarray analysis and were validated using real-time quarttitative polymerase chain reaction.Results:The vascular number of granulation tissues at both 36 and 48 h were characterized by new and fresh vessels.The number of angiogenesis in the high-dose XZC group at 36 and 48 h was greater compared with that in the regular-dose XZC and model groups(P<0.01),and high-dose XZC at 36 h increased more vessels than that at 48 h(P<0.01).Consequently,granulation tissues from the high-dose XZC group at 36 h were chosen for microarray analysis.In all,2,085 differentially expressed genes(DEGs)were detected and 25 DEGs were determined to be directly related to an giogenesis.Four biological process terms were found including an giogenesis,regulati on of an gioge nesis,positive regulati on of an giogenesis,and positive regulation of vascular end othelial growth factor receptor sign aling pathway(P<0.05).Microarray an alysis also showed 49 pathways including 11 pathways related to an giogenesis.Conclusion:XZC promoted angiogenesis moderately and the mechanism invoIved multiple DEGs and multiple pathways.
基金supported by a Grant-in-Aid for Challenging Exploratory Research(No.26670044)from the Ministry of Education,Culture,Sports,Science,and Technology of Japan(to CT)a Grant-in-Aid for a Cooperative Research Project from the Institute of Natural Medicine,University of Toyama,in 2014 and 2015(to CT)+1 种基金discretionary funds of the President of the University of Toyama,in 2014,2015,and 2016(to CT)the Natural Medicine and Biotechnology Research of Toyama Prefecture,Japan(to CT)
文摘In chronic phase of spinal cord injury, functional recovery is more untreatable compared with early intervention in acute phase of spinal cord injury. In the last decade, several combination therapies successfully improved motor dysfunction in chronic spinal cord injury. However, their effectiveness is not sufficient. We previously found a new effective compound for spinal cord injury, matrine, which induced axonal growth and functional recovery in acute spinal cord injury mice via direct activation of extracellular heat shock protein 90. Although our previous study clarified that matrine was an activator of extracellular heat shock protein 90, the potential of matrine for spinal cord injury in chronic phase has not been sufficiently evaluated. Thus, this study aimed to investigate whether matrine ameliorates chronic spinal cord injury in mice. Once daily intragastric administration of matrine(100 μmol/kg per day) to spinal cord injury mice were starte at 28 days after injury, and continued for 154 days. Continuous mat rine treatment improved hindlimb motor function in chronic spinal cord injury mice. In injured spinal cords of the matrine-treated mice, the density of neurofilament-H-positive axons was increased. Moreover, matrine treatment increased the density of bassoon-positive presynapses in contact with choline acetyltransferase-positive motor neurons in the lumbar spinal cord. These findings suggest that matrine promotes remodeling and reconnection of neural circuits to regulate hindlimb movement. All protocols were approved by the Committee for Animal Care and Use of the Sugitani Campus of the University of Toyama(approval No. A2013 INM-1 and A2016 INM-3) on May 7, 2013 and May 17, 2016, respectively.
基金partially supported by the Canadian Institutes for Health Research(CIHR MOP-142288 to MM)+1 种基金supported by a salary award from Fonds de Recherche Québec Santé(FRQS)ARB was supported by a fellowship from FRQS
文摘Spinal cord injury is associated with chronic sensorimotor deficits due to the interruption of ascending and descending tracts between the brain and spinal cord. Functional recovery after anatomically complete spinal cord injury is limited due to the lack of long-distance axonal regeneration of severed fibers in the adult central nervous system. Most spinal cord injuries in humans, however, are anatomically incomplete. Although restorative treatment options for spinal cord injury remain currently limited, research from experimental models of spinal cord injury have revealed a tremendous capability for both spontaneous and treatment-induced plasticity of the corticospinal system that supports functional recovery. We review recent advances in the understanding of corticospinal circuit plasticity after spinal cord injury and concentrate mainly on the hindlimb motor cortex, its corticospinal projections, and the role of spinal mechanisms that support locomotor recovery. First, we discuss plasticity that occurs at the level of motor cortex and the reorganization of cortical movement representations. Next, we explore downstream plasticity in corticospinal projections. We then review the role of spinal mechanisms in locomotor recovery. We conclude with a perspective on harnessing neuroplasticity with therapeutic interventions to promote functional recovery.
文摘目的:NOD样受体热蛋白结构域相关蛋白6(NOD-like receptor thermal protein domain associated protein 6,NLRP6)是新发现的寡聚化核苷酸结合结构域样受体家族成员,广泛表达于肠道、肝脏、肾脏、脾脏和肌肉等组织器官,在炎症、焦亡和自噬等多种生物过程发挥广泛的调节作用。近期研究表明,NLRP6在应激条件下对多种组织器官的疾病表型具有重要影响。然而,NLRP6对组织器官生长发育的影响尚未可知。方法:采用CRISPR/Cas9基因编辑技术构建NLRP6基因敲除小鼠,饲养并记录小鼠的生长和繁殖情况。将小鼠的脾、肝、心、肾、脑、四肢和后背皮肤等组织器官进行解剖和切片染色,以评估NLRP6基因敲除对实质器官的宏观发育影响和对组织结构的微观影响。结果:在自然状态下,NLRP6基因敲除缩短了雄鼠的性成熟期并使成年雄鼠的睾丸发生不可逆的破溃与萎缩。在四肢发育上,NLRP6基因敲除诱导成年雄鼠后肢横纹肌断裂,导致后肢明显萎缩。在脾脏发育上,NLRP6基因敲除不仅显著增加了雄鼠的脾脏体积(P<0.01)还诱导雄鼠脾脏出现炎性细胞浸润。在后背皮肤上,NLRP6基因敲除引发雄鼠后背皮肤出现明显的溃疡损伤、胶原纤维增生和炎性细胞浸润。结论:在自然生长发育条件下,NLRP6基因敲除选择性影响小鼠的生殖器发育与性成熟期、后肢肌肉发育、脾脏大小及其炎症免疫状态以及后背皮肤的结构完整性,而且这一作用具有明显的雄激素依赖性。
基金supported by the National Natural Science Foundationof China (No. 33372201)。
文摘The endochondral ossification of hindlimb is essential to a bird’s ability to stand,walk and fly.Most hindlimb is ossified in the embryos before hatching in precocial birds.However,the molecular mechanisms of hindlimb ossification in birds is still unclear.Therefore,we tried to examine the process of hindlimb ossification and its molecular regulation by using an animal model—Japanese Quail(Coturnix japonica).We selected four critical stages(Embryo Day:E6,E8,E12 and E16) of skeletal development of embryonic quails for hindlimb skeleton staining to show the process of endochondral ossification and to examine the molecular regulation of endochondral osteogenesis by RNA-Seq analysis.The results showed that ossification became increased with embryonic development and most hindlimb was ossified before hatching.RNA-Seq analysis revealed that various signaling pathways were involved with endochondral ossification with thyroid hormone signaling and WNT signaling pathway particularly enriched.Moreover,the expression levels of 42 genes were continuously upregulated and 14 genes were continuously downregulated from E6 to E16.The present study might provide new insights into complex molecular mechanisms in regulation of endochondral ossification.
基金Supported by grant from the National Sci-Tech Program,Ministry of Science and Technology,No.NRMPG3E0471 and No.NMRPG3D0231a Chang Gung Memorial Hospital grant,No.CMRPGBH0011
文摘AIM To evaluate the angiogenic effect of platelet-rich plasma(PRP)-preconditioned adipose-derived stem cells(ADSCs) both in vitro and in a mouse ischemic hindlimb model.METHODS ADSCs were divided based on culture medium: 2.5% PRP, 5% PRP, 7.5% PRP, and 10% PRP. Cell proliferation rate was analyzed using the MTS assay. The gene expression of CD31, vascular endothelial growth factor, hypoxia-inducible factors, and endothelial cell nitric oxide synthase was analyzed using reverse transcription polymerase chain reaction. Cell markers and structural changes were assessed through immunofluorescence staining and the tube formation assay. Subsequently, we studied the in vivo angiogenic capabilities of ADSCs by a mouse ischemic hindlimb model.RESULTS The proliferation rate of ADSCs was higher in the 2.5%, 5%, and 7.5% PRP groups. The expression of hypoxia-inducible factor, CD31, vascular endothelial growth factor, and endothelial cell nitric oxide synthase in the 5% and 7.5% PRP groups increased. The 5%, 7.5%, and 10% PRP groups showed higher abilities to promote both CD31 and vascular endothelial growth factor production and tubular structure formation in ADSCs. According to laser Doppler perfusion scan, the perfusion ratios of ischemic limb to normal limb were significantly higher in 5% PRP, 7.5% PRP, and human umbilical vein endothelial cells groups compared with the negative control and fetal bovine serum(FBS) groups(0.88 ± 0.08, 0.85 ± 0.07 and 0.81 ± 0.06 for 5%, 7.5% PRP and human umbilical vein endothelial cells compared with 0.42 ± 0.17 and 0.54 ± 0.14 for the negative control and FBS, P < 0.01).CONCLUSION PRP-preconditioned ADSCs presented endothelial cell characteristics in vitro and significantly improved neovascularization in ischemic hindlimbs. The optimal angiogenic effect occurred in 5% PRP-and 7.5% PRPpreconditioned ADSCs.
基金supported by the National Natural Science Foundation of China,No.31400824a grant from the Science and Technology Program of Jiangmen City of China,No.2015751the Scientific Research and Cultivating Foundation of the First Clinical Medical College of Jinan University of China,No.2013208
文摘Non-traumatic injury accounts for approximately half of clinical spinal cord injury, including chronic spinal cord compression. However, previous rodent spinal cord compression models are mainly designed for rats, few are available for mice. Our aim is to develop a thoracic progressive compression mice model of spinal cord injury. In this study, adult wild-type C57BL/6 mice were divided into two groups： in the surgery group, a screw was inserted at T9 lamina to compress the spinal cord, and the compression was increased by turning it further into the canal（0.2 mm） post-surgery every 2 weeks up to 8 weeks. In the control group, a hole was drilled into the lamina without inserting a screw. The results showed that Basso Mouse Scale scores were lower and gait worsened. In addition, the degree of hindlimb dysfunction in mice was consistent with the degree of spinal cord compression. The number of motor neurons in the anterior horn of the spinal cord was reduced in all groups of mice, whereas astrocytes and microglia were gradually activated and proliferated. In conclusion, this progressive compression of thoracic spinal cord injury in mice is a preferable model for chronic progressive spinal cord compression injury.
文摘Assessment of locomotion recovery in preclinical studies of experimental spinal cord injury remains challenging. We studied the CatWalk XT■gait analysis for evaluating hindlimb functional recovery in a widely used and clinically relevant thoracic contusion/compression spinal cord injury model in rats. Rats were randomly assigned to either a T9 spinal cord injury or sham laminectomy. Locomotion recovery was assessed using the Basso, Beattie, and Bresnahan open field rating scale and the CatWalk XT■gait analysis. To determine the potential bias from weight changes, corrected hindlimb(H) values(divided by the unaffected forelimb(F) values) were calculated. Six weeks after injury, cyst formation, astrogliosis, and the deposition of chondroitin sulfate glycosaminoglycans were assessed by immunohistochemistry staining. Compared with the baseline, a significant spontaneous recovery could be observed in the CatWalk XT■parameters max intensity, mean intensity, max intensity at%, and max contact mean intensity from 4 weeks after injury onwards. Of note, corrected values(H/F) of CatWalk XT■parameters showed a significantly less vulnerability to the weight changes than absolute values, specifically in static parameters. The corrected CatWalk XT■parameters were positively correlated with the Basso, Beattie, and Bresnahan rating scale scores, cyst formation, the immunointensity of astrogliosis and chondroitin sulfate glycosaminoglycan deposition. The CatWalk XT■gait analysis and especially its static parameters, therefore, seem to be highly useful in assessing spontaneous recovery of hindlimb function after severe thoracic spinal cord injury. Because many CatWalk XT■parameters of the hindlimbs seem to be affected by body weight changes, using their corrected values might be a valuable option to improve this dependency.
基金supported by the National Natural Science Foundation of China(grant number:82270415)Key Project Fund of Natural Science Foundation of Fujian Science and Technology Department(grant number:2021GGB030)+8 种基金Shanghai Municipal Science and Technology Commission Innovation Fund(grant number:22S31904800)Fudan Zhangjiang Clinical Medicine Innovation Fund(grant number:KP7202115)Fujian Province Health Science and Technology Fund(grant number:2021GGB030)the National Natural Science Foundation of China(grant number:81970412)Medical-Industrial Cooperation Project of Zhongshan Hospital Affiliated to Fudan University(grant number:MP2021Q2C018)National Clinical Research Center for Interventional Medicine Fund(grant number:2021-004)Xiamen Municipal Health Science And Technology Program Fund(grant number:3502Z20194034)Zhongshan hospital’s Talents Supporting Plan(grant number:2019ZSGG11)Shanghai Municipal Science and Technology Commission Innovation Fund(grant number:18441902400).
文摘Muscle necrosis and angiogenesis are two major challenges in the treatment of lower-limb ischemic diseases.In this study,a triple-functional Sr/Si-containing bioceramic/alginate composite hydrogel with simultaneous bioactivity in enhancing angiogenesis,regulating inflammation,and inhibiting muscle necrosis was designed to treat lower-limb ischemic diseases.In particular,sodium alginate,calcium silicate and strontium carbonate were used to prepare injectable hydrogels,which was gelled within 10 min.More importantly,this composite hydrogel sustainedly releases bioactive Sr^(2+)and SiO_(3)^(2-) ions within 28 days.The biological activity of the bioactive ions released from the hydrogels was verified on HUVECs,SMCs,C2C12 and Raw 264.7 cells in vitro,and the therapeutic effect of the hydrogel was confirmed using C57BL/6 mouse model of femoral artery ligation in vivo.The results showed that the composite hydrogel stimulated angiogenesis,developed new collateral capillaries,and re-established the blood supply.In addition,the bioactive hydrogel directly promoted the expression of muscle-regulating factors(MyoG and MyoD)to protect skeletal muscle from necrosis,inhibited M1 polarization,and promoted M2 polarization of macrophages to reduce inflammation,thereby protecting skeletal muscle cells and indirectly promoting vascularization.Our results indicate that these bioceramic/alginate composite bioactive hydrogels are effective biomaterials for treating hindlimb ischemia and suggest that biomaterial-based approaches may have remarkable potential in treating ischemic diseases.
基金supported by the National Natural Science Foundation of China(31101633)the Innovative Team Foundation of China West Normal University
文摘In many anurans, the forelimb muscles of males are used to grasp females and are often heavier than those of females despite the larger female body size. Such sexual dimorphism in forelimb musculature is thought to result from sexual selection. In addition, the hindlimbs of frogs and toads play an important role in the reproductive process as amplectant males can expel rivals with robust hindlimbs through kicking. In this study, the sexual dimorphism in dry mass for six hindlimb muscles of the Asiatic toad （Bufo gargarizans） was investigated. The results showed that, when controlled for body size, the hindlimb muscle mass of males significantly exceeded that of females for every muscle. The hindlimb muscle mass of amplectant males was also significantly larger than that of non-amplectant males. These results suggested that if strong hindlimb muscles could improve mating success of males, sexual selection would promote the evolution of dimorphism in this character.
