Sericin from discarded silkworm cocoons of silk reeling has been used in different fields, such as cosmetology, skin care, nutrition, and oncology. The present study established a rat model of type 2 diabetes by conse...Sericin from discarded silkworm cocoons of silk reeling has been used in different fields, such as cosmetology, skin care, nutrition, and oncology. The present study established a rat model of type 2 diabetes by consecutive intraperitoneal injections of low-dose （25 mg/kg） streptozotocin. After intragastrical perfusion of sericin for 35 days, blood glucose levels significantly declined, and the expression of neurofilament protein in the sciatic nerve and nerve growth factor in L4-6 spinal ganglion and anterior horn cells significantly increased. However, the expression of neuropeptide Y in spinal ganglion and anterior horn cells significantly decreased in model rats. These findings indicate that sericin protected the sciatic nerve and related nerve cells against injury in a rat type 2 diabetic model by upregulating the expression of neurofilament protein in the sciatic nerve and nerve growth factor in spinal ganglion and anterior horn cells, and downregulating the expression of neuropeptide Y in spinal ganglion and anterior horn cells.展开更多
Molecular mechanisms of the Kruppel-like family of transcription factors （KLFs） have been studied more in proliferating cells than in post-mitotic cells such as neurons. We recently found that KLFs regulate intrinsi...Molecular mechanisms of the Kruppel-like family of transcription factors （KLFs） have been studied more in proliferating cells than in post-mitotic cells such as neurons. We recently found that KLFs regulate intrinsic axon growth ability in central nervous system （CNS） neurons in- cluding retinal ganglion cells, and hippocampal and cortical neurons. With at least 15 of 17 KLF family members expressed in neurons and at least 5 structurally unique subfamilies, it is import- ant to determine how this complex family functions in neurons to regulate the intricate genetic programs of axon growth and regeneration. By characterizing the molecular mechanisms of the KLF family in the nervous system, including binding partners and gene targets, and comparing them to defined mechanisms defined outside the nervous system, we may better understand how KLFs regulate neurite growth and axon regeneration.展开更多
The canonical Wnt/β-catenin pathway is a highly conserved signaling cascade that plays critical roles during embryogenesis. Wnt ligands regulate axonal extension, growth cone guidance and synaptogenesis throughout th...The canonical Wnt/β-catenin pathway is a highly conserved signaling cascade that plays critical roles during embryogenesis. Wnt ligands regulate axonal extension, growth cone guidance and synaptogenesis throughout the developing central nervous system （CNS）. Recently, studies in mammalian and fish model systems have demonstrated that Wnt/β-catenin signaling also promotes axonal regeneration in the adult optic nerve and spinal cord after injury, raising the possibility that Wnt could be developed as a therapeutic strategy. In this review, we summarize experimental evidence that reveals novel roles for Wnt signaling in the injured CNS, and discuss possible mechanisms by which Wnt ligands could overcome molecular barriers inhibiting axonal growth to promote regeneration. A central challenge in the neuroscience field is developing therapeutic strategies that induce robust axonal regeneration. Although adult axons have the capacity to respond to axonal guidance molecules after injury, there are several major obstacles for axonal growth, including extensive neuronal death, glial scars at the injury site, and lack of axonal guidance signals. Research in rodents demonstrated that activation of Wnt/β-catenin signaling in retinal neurons and radial glia induced neuronal survival and axonal growth, but that activation within reactive glia at the injury site promoted proliferation and glial scar formation. Studies in zebrafish spinal cord injury models confirm an axonal regenerative role for Wnt/β-catenin signaling and identified the cell types responsible. Additionally, in vitro and in vivo studies demonstrated that Wnt induces axonal and neurite growth through transcription-dependent effects of its central mediator β-catenin, potentially by inducing regeneration-promoting genes. Canonical Wnt signaling may also function through transcription-independent interactions of β-catenin with cytoskeletal elements, which could stabilize growing axons and control growth cone movement. Therefore, these studies suggest that Wnt-induced pathways responsible for regulating axonal growth during embryogenesis could be repurposed to promote axonal growth after injury.展开更多
文摘目的 探讨男性复杂肛门直肠畸形(anorectal malformations,ARMs)患儿直肠末端神经发育情况与患者脊髓/骶骨异常的关系,以期提高对ARMs中肠神经发育异常的相关认识。方法 回顾性收集我院2015-2021年收治符合纳排标准的男性复杂ARMs患儿的临床资料,在肛门成形术时取患者末端直肠标本,采用苏木精-伊红染色后显微镜下观察神经节发育情况并进行分组(G1组:有神经节细胞;G2组:无神经节细胞)。利用影像学技术评估患者脊髓及骶骨是否存在异常,并将其与直肠末端肠神经节发育情况进行相关性分析。结果 本研究共纳入患者139例,行肛门成形术时中位年龄为5.77(4.57,6.97)个月。G1组(80例,57.6%)与G2组(59例,42.4%)在ARMs病理类型、手术年龄的差异无统计学意义。经影像学证实出现脊髓异常(SCA)48例(34.5%),骶骨发育异常25例(18.0%),尾骨发育异常18例(12.9%)。G1组与G2组脊髓发育不良及骶骨发育异常发生率的差异具有统计学意义(P<0.05);在脊髓发育不良中,终丝脂肪变性、脊髓空洞的差异具有统计学意义(P<0.05)。G1组、G2组正位及侧位SR值分别为(0.72±0.10 vs 0.67±0.12)、(0.77±0.09 vs 0.72±0.09),差异有统计学意义(P<0.05)。将相关因素纳入多因素Logistic回归分析,结果显示骶骨发育异常、终丝脂肪变、脊髓空洞为男性复杂ARMs患儿直肠末端神经节缺失的独立预测因素。结论 男性复杂性ARMs直肠末端神经节发育情况与脊髓及骶骨发育异常密切相关。骶骨发育异常、终丝脂肪变、脊髓空洞为男性复杂ARMs患儿直肠末端神经节缺失的独立预测因素。
文摘Sericin from discarded silkworm cocoons of silk reeling has been used in different fields, such as cosmetology, skin care, nutrition, and oncology. The present study established a rat model of type 2 diabetes by consecutive intraperitoneal injections of low-dose （25 mg/kg） streptozotocin. After intragastrical perfusion of sericin for 35 days, blood glucose levels significantly declined, and the expression of neurofilament protein in the sciatic nerve and nerve growth factor in L4-6 spinal ganglion and anterior horn cells significantly increased. However, the expression of neuropeptide Y in spinal ganglion and anterior horn cells significantly decreased in model rats. These findings indicate that sericin protected the sciatic nerve and related nerve cells against injury in a rat type 2 diabetic model by upregulating the expression of neurofilament protein in the sciatic nerve and nerve growth factor in spinal ganglion and anterior horn cells, and downregulating the expression of neuropeptide Y in spinal ganglion and anterior horn cells.
基金the National Eye Institute(EY022129 to JLGP30-EY022589 to UCSD)+1 种基金the DOD(W81XWH-12-1-0254 to JLG)an unrestricted grant from Research to Prevent Blindness,Inc
文摘Molecular mechanisms of the Kruppel-like family of transcription factors （KLFs） have been studied more in proliferating cells than in post-mitotic cells such as neurons. We recently found that KLFs regulate intrinsic axon growth ability in central nervous system （CNS） neurons in- cluding retinal ganglion cells, and hippocampal and cortical neurons. With at least 15 of 17 KLF family members expressed in neurons and at least 5 structurally unique subfamilies, it is import- ant to determine how this complex family functions in neurons to regulate the intricate genetic programs of axon growth and regeneration. By characterizing the molecular mechanisms of the KLF family in the nervous system, including binding partners and gene targets, and comparing them to defined mechanisms defined outside the nervous system, we may better understand how KLFs regulate neurite growth and axon regeneration.
基金provided by the NEI grant R01EY026546AU is a recipient of a Research to Prevent Blindness Medical Student Eye Research Fellowship+2 种基金Financial support from Fight for Sight(summer student fellowship to AU)is gratefully acknowledgedInstitutional support is from an NIH Center Core Grant P30EY014801a Research to Prevent Blindness Unrestricted Grant
文摘The canonical Wnt/β-catenin pathway is a highly conserved signaling cascade that plays critical roles during embryogenesis. Wnt ligands regulate axonal extension, growth cone guidance and synaptogenesis throughout the developing central nervous system （CNS）. Recently, studies in mammalian and fish model systems have demonstrated that Wnt/β-catenin signaling also promotes axonal regeneration in the adult optic nerve and spinal cord after injury, raising the possibility that Wnt could be developed as a therapeutic strategy. In this review, we summarize experimental evidence that reveals novel roles for Wnt signaling in the injured CNS, and discuss possible mechanisms by which Wnt ligands could overcome molecular barriers inhibiting axonal growth to promote regeneration. A central challenge in the neuroscience field is developing therapeutic strategies that induce robust axonal regeneration. Although adult axons have the capacity to respond to axonal guidance molecules after injury, there are several major obstacles for axonal growth, including extensive neuronal death, glial scars at the injury site, and lack of axonal guidance signals. Research in rodents demonstrated that activation of Wnt/β-catenin signaling in retinal neurons and radial glia induced neuronal survival and axonal growth, but that activation within reactive glia at the injury site promoted proliferation and glial scar formation. Studies in zebrafish spinal cord injury models confirm an axonal regenerative role for Wnt/β-catenin signaling and identified the cell types responsible. Additionally, in vitro and in vivo studies demonstrated that Wnt induces axonal and neurite growth through transcription-dependent effects of its central mediator β-catenin, potentially by inducing regeneration-promoting genes. Canonical Wnt signaling may also function through transcription-independent interactions of β-catenin with cytoskeletal elements, which could stabilize growing axons and control growth cone movement. Therefore, these studies suggest that Wnt-induced pathways responsible for regulating axonal growth during embryogenesis could be repurposed to promote axonal growth after injury.
