Anti-microbial peptides are essential for the intestinal innate immunity that protects the intestinal epithelia from attacks by foreign pathogens. Human β-defensin (HBD) is one of the pivotal anti-microbial peptides ...Anti-microbial peptides are essential for the intestinal innate immunity that protects the intestinal epithelia from attacks by foreign pathogens. Human β-defensin (HBD) is one of the pivotal anti-microbial peptides that are expressed in the colonic epithelia. This study investigated the effect and the signaling mechanism of inducible β-defensin HBD2 by an essential amino acid, isoleucine (Ile) in colonic epithelial cells. Here we examined the expression level of HBD2 on induction of Ile in epithelial cells, and checked this pathway. HBD2 mRNA was induced by co-incubation with IL-1α and Ile in Caco2 cells, but not by Ile alone. An inhibitor of either ERK or Gi, a subunit of G-proteins, reduced the induction of HBD2 mRNA by Ile. The treatment with Ile also increased the intracellular calcium ion concentration, thus suggesting that the GPCR and ERK signaling pathway mediate the effects of Ile. These results indicate that an essential amino acid, Ile, enhances the expression of an inducible β-defensin, namely HBD2, by IL-1α through the activation of GPCRs and ERK signaling pathway. The administration of Ile may therefore represent a possible option to safely treat intestinal inflammation.展开更多
Levodopa is the gold-standard treatment for Parkinson's disease. However, although it alleviates the clinical symptoms, it cannot delay the progressive apoptosis of dopaminergic neurons or prevent motor complicati...Levodopa is the gold-standard treatment for Parkinson's disease. However, although it alleviates the clinical symptoms, it cannot delay the progressive apoptosis of dopaminergic neurons or prevent motor complications in the long term. In the present study, we investigated the effect of Shudipingchan granule on neuronal apoptosis in a rat model of Parkinson's disease, established by injecting 6-hydroxydopamine into the substantia nigra pars compacta and ventral tegmental area. We then administered levodopa(20 mg/kg intraperitoneally, twice daily) with or without Shudipingchan granule(7.5 m L/kg intragastrically, twice daily), for 4 weeks. The long-term use of levodopa accelerated apoptosis of nigral cells and worsened behavioral symptoms by activating the extracellular signal-regulated kinase pathway and downstream apoptotic factors. However, administration of Shudipingchan granule with levodopa reduced expression of phosphorylated extracellular signal-regulated kinase 1/2 and Bax, increased tyrosine hydroxylase and Bcl-2, reduced apoptosis in the substantia nigra, and markedly improved dyskinesia. These findings suggest that Shudipingchan granule suppresses neuronal apoptosis by inhibiting the hyperphosphorylation of extracellular signal-regulated kinase and downregulating expression of anti-apoptotic genes. Shudipingchan granule, used in combination with levodopa, can effectively reduce the symptoms of Parkinson's disease.展开更多
Peripheral nerve injury repair requires a certain degree of cooperation between axon regeneration and Wallerian degeneration.Therefore,investigating how axon regeneration and degeneration work together to repair perip...Peripheral nerve injury repair requires a certain degree of cooperation between axon regeneration and Wallerian degeneration.Therefore,investigating how axon regeneration and degeneration work together to repair peripheral nerve injury may uncover the molecular mechanisms and signal cascades underlying peripheral nerve repair and provide potential strategies for improving the low axon regeneration capacity of the central nervous system.In this study,we applied weighted gene co-expression network analysis to identify differentially expressed genes in proximal and distal sciatic nerve segments from rats with sciatic nerve injury.We identified 31 and 15 co-expression modules from the proximal and distal sciatic nerve segments,respectively.Functional enrichment analysis revealed that the differentially expressed genes in proximal modules promoted regeneration,while the differentially expressed genes in distal modules promoted neurodegeneration.Next,we constructed hub gene networks for selected modules and identified a key hub gene,Kif22,which was up-regulated in both nerve segments.In vitro experiments confirmed that Kif22 knockdown inhibited proliferation and migration of Schwann cells by modulating the activity of the extracellular signal-regulated kinase signaling pathway.Collectively,our findings provide a comparative framework of gene modules that are co-expressed in injured proximal and distal sciatic nerve segments,and identify Kif22 as a potential therapeutic target for promoting peripheral nerve injury repair via Schwann cell proliferation and migration.All animal experiments were approved by the Institutional Animal Ethics Committee of Nantong University,China(approval No.S20210322-008)on March 22,2021.展开更多
Objective:To investigate the therapeutic and synergistic effects of QHC(combination of quercetin(Q),hirudin(H)and cinnamaldehyd(C))on Schwann cell differentiation and myelination against high glucose(HG)induced injury...Objective:To investigate the therapeutic and synergistic effects of QHC(combination of quercetin(Q),hirudin(H)and cinnamaldehyd(C))on Schwann cell differentiation and myelination against high glucose(HG)induced injury.Methods:Primary-culture Schwann cells exposed to HG(50 mmol/L)for 72 h and Schwann cell–dorsal root ganglion(DRG)neuron cocultures exposed to HG(50 mmol/L)for 7 days were employed as in vitro model of diabetic neuropathy.The cells were randomly divided into 10 groups:control(CON,25 mmol/L glucose),HG(50 mmol/L glucose),HG plus 10μmol/L quercetin(Q),HG plus 0.04 IU/mL hirudin(H),HG plus 100 nmol/L cinnamaldehyd(C),HG plus 10μmol/L quercetin and 0.04 IU/mL hirudin(QH),HG plus 10μmol/L quercetin and 50 nmol/L cinnamaldehyd(QC),HG plus 0.04 IU/mL hirudin and 50 nmol/L cinnamaldehyd(HC),HG plus 10μmol/L quercetin,0.04 IU/mL hirudin and 50 nmol/L cinnamaldehyd(QHC)or 10μmol/L U0126.Cell differentiation was evaluated by periaxin immunofluorescence staining.The protein expression levels of myelin protein zero(P0),myelin basic protein(MBP),myelin-associated glycoprotein(MAG),extracellular signal-regulated kinase(ERK),p-ERK,p-c-Jun,c-Jun,notch intracellular domain(NICD)and the mRNA expression levels of P0,MBP,MAG,Krox-20,Notch1 and Jagged1 were detected by Western blotting and real-time quantitative PCR analysis.The secretion of ciliary neurotrophic factor(CNTF)was determined by enzyme-linked immunosorbent assay(ELISA).The number and length of the myelin segments were evaluated by MBP immunofluorescence staining.The expression and the location of p-ERK in cocultures were detected by MAG and p-ERK immunofluorescence double staining.Results:Co-treatment with Q,C,H and their combination promoted Schwann cell differentiation,increased CNTF secretion,up-regulated the protein and m RNA expressions of myelin,and increased the number and length of the myelin segments(P<0.01 or P<0.05).In particular,the combination therapy of Q,H and C was superior to the respective monotherapy(P<0.01).Combination therapy of QHC exhibited higher inhibitory activities for ERK signaling related molecules than each monomer or the combination of the two monomers(P<0.01).Conclusions:QHC combination yielded synergy in promoting Schwann cell differentiation and myelination and the protective effect may involve in the inhibition of ERK signaling pathway,providing scientific evidence for better understanding of combination of Q,H and C in clinical applications.展开更多
文摘Anti-microbial peptides are essential for the intestinal innate immunity that protects the intestinal epithelia from attacks by foreign pathogens. Human β-defensin (HBD) is one of the pivotal anti-microbial peptides that are expressed in the colonic epithelia. This study investigated the effect and the signaling mechanism of inducible β-defensin HBD2 by an essential amino acid, isoleucine (Ile) in colonic epithelial cells. Here we examined the expression level of HBD2 on induction of Ile in epithelial cells, and checked this pathway. HBD2 mRNA was induced by co-incubation with IL-1α and Ile in Caco2 cells, but not by Ile alone. An inhibitor of either ERK or Gi, a subunit of G-proteins, reduced the induction of HBD2 mRNA by Ile. The treatment with Ile also increased the intracellular calcium ion concentration, thus suggesting that the GPCR and ERK signaling pathway mediate the effects of Ile. These results indicate that an essential amino acid, Ile, enhances the expression of an inducible β-defensin, namely HBD2, by IL-1α through the activation of GPCRs and ERK signaling pathway. The administration of Ile may therefore represent a possible option to safely treat intestinal inflammation.
基金financially supported by the National Natural Science Foundation of China,No.81302926,30472207the Major Project of Shanghai Science and Technology Commission of China,No.15401970100the Shanghai Municipal Commission of Health and Family Planning of China,No.ZY3-RCPY-2-2005
文摘Levodopa is the gold-standard treatment for Parkinson's disease. However, although it alleviates the clinical symptoms, it cannot delay the progressive apoptosis of dopaminergic neurons or prevent motor complications in the long term. In the present study, we investigated the effect of Shudipingchan granule on neuronal apoptosis in a rat model of Parkinson's disease, established by injecting 6-hydroxydopamine into the substantia nigra pars compacta and ventral tegmental area. We then administered levodopa(20 mg/kg intraperitoneally, twice daily) with or without Shudipingchan granule(7.5 m L/kg intragastrically, twice daily), for 4 weeks. The long-term use of levodopa accelerated apoptosis of nigral cells and worsened behavioral symptoms by activating the extracellular signal-regulated kinase pathway and downstream apoptotic factors. However, administration of Shudipingchan granule with levodopa reduced expression of phosphorylated extracellular signal-regulated kinase 1/2 and Bax, increased tyrosine hydroxylase and Bcl-2, reduced apoptosis in the substantia nigra, and markedly improved dyskinesia. These findings suggest that Shudipingchan granule suppresses neuronal apoptosis by inhibiting the hyperphosphorylation of extracellular signal-regulated kinase and downregulating expression of anti-apoptotic genes. Shudipingchan granule, used in combination with levodopa, can effectively reduce the symptoms of Parkinson's disease.
基金supported by the National Major Project of Research and Development of China,No.2017YFA0104701(to BY)the National Natural Science Foundation of China,No.32000725(to QQC)+1 种基金the Natural Science Foundation of Jiangsu Province of China,No.BK20200973(to QQC)the Jiangsu Provincial University Innovation Training Key Project of China,No.202010304021Z(to ML)。
文摘Peripheral nerve injury repair requires a certain degree of cooperation between axon regeneration and Wallerian degeneration.Therefore,investigating how axon regeneration and degeneration work together to repair peripheral nerve injury may uncover the molecular mechanisms and signal cascades underlying peripheral nerve repair and provide potential strategies for improving the low axon regeneration capacity of the central nervous system.In this study,we applied weighted gene co-expression network analysis to identify differentially expressed genes in proximal and distal sciatic nerve segments from rats with sciatic nerve injury.We identified 31 and 15 co-expression modules from the proximal and distal sciatic nerve segments,respectively.Functional enrichment analysis revealed that the differentially expressed genes in proximal modules promoted regeneration,while the differentially expressed genes in distal modules promoted neurodegeneration.Next,we constructed hub gene networks for selected modules and identified a key hub gene,Kif22,which was up-regulated in both nerve segments.In vitro experiments confirmed that Kif22 knockdown inhibited proliferation and migration of Schwann cells by modulating the activity of the extracellular signal-regulated kinase signaling pathway.Collectively,our findings provide a comparative framework of gene modules that are co-expressed in injured proximal and distal sciatic nerve segments,and identify Kif22 as a potential therapeutic target for promoting peripheral nerve injury repair via Schwann cell proliferation and migration.All animal experiments were approved by the Institutional Animal Ethics Committee of Nantong University,China(approval No.S20210322-008)on March 22,2021.
基金Supported by the National Natural Science Foundation of China(No.81473639)the Youth Scientific Research Foundation of Peking Union Medical College(No.33320140118)。
文摘Objective:To investigate the therapeutic and synergistic effects of QHC(combination of quercetin(Q),hirudin(H)and cinnamaldehyd(C))on Schwann cell differentiation and myelination against high glucose(HG)induced injury.Methods:Primary-culture Schwann cells exposed to HG(50 mmol/L)for 72 h and Schwann cell–dorsal root ganglion(DRG)neuron cocultures exposed to HG(50 mmol/L)for 7 days were employed as in vitro model of diabetic neuropathy.The cells were randomly divided into 10 groups:control(CON,25 mmol/L glucose),HG(50 mmol/L glucose),HG plus 10μmol/L quercetin(Q),HG plus 0.04 IU/mL hirudin(H),HG plus 100 nmol/L cinnamaldehyd(C),HG plus 10μmol/L quercetin and 0.04 IU/mL hirudin(QH),HG plus 10μmol/L quercetin and 50 nmol/L cinnamaldehyd(QC),HG plus 0.04 IU/mL hirudin and 50 nmol/L cinnamaldehyd(HC),HG plus 10μmol/L quercetin,0.04 IU/mL hirudin and 50 nmol/L cinnamaldehyd(QHC)or 10μmol/L U0126.Cell differentiation was evaluated by periaxin immunofluorescence staining.The protein expression levels of myelin protein zero(P0),myelin basic protein(MBP),myelin-associated glycoprotein(MAG),extracellular signal-regulated kinase(ERK),p-ERK,p-c-Jun,c-Jun,notch intracellular domain(NICD)and the mRNA expression levels of P0,MBP,MAG,Krox-20,Notch1 and Jagged1 were detected by Western blotting and real-time quantitative PCR analysis.The secretion of ciliary neurotrophic factor(CNTF)was determined by enzyme-linked immunosorbent assay(ELISA).The number and length of the myelin segments were evaluated by MBP immunofluorescence staining.The expression and the location of p-ERK in cocultures were detected by MAG and p-ERK immunofluorescence double staining.Results:Co-treatment with Q,C,H and their combination promoted Schwann cell differentiation,increased CNTF secretion,up-regulated the protein and m RNA expressions of myelin,and increased the number and length of the myelin segments(P<0.01 or P<0.05).In particular,the combination therapy of Q,H and C was superior to the respective monotherapy(P<0.01).Combination therapy of QHC exhibited higher inhibitory activities for ERK signaling related molecules than each monomer or the combination of the two monomers(P<0.01).Conclusions:QHC combination yielded synergy in promoting Schwann cell differentiation and myelination and the protective effect may involve in the inhibition of ERK signaling pathway,providing scientific evidence for better understanding of combination of Q,H and C in clinical applications.
