Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal sur...Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic function.Increasing amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of cancers.These findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative diseases.Through a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.展开更多
AIM To explore the role and mechanism of total flavone of Abelmoschus manihot(TFA) on epithelial-mesenchymal transition(EMT) progress of Crohn's disease(CD) intestinal fibrosis.METHODS First,CCK-8 assay was perfor...AIM To explore the role and mechanism of total flavone of Abelmoschus manihot(TFA) on epithelial-mesenchymal transition(EMT) progress of Crohn's disease(CD) intestinal fibrosis.METHODS First,CCK-8 assay was performed to assess TFA on the viability of intestinal epithelial(IEC-6) cells and select the optimal concentrations of TFA for our further studies.Then cell morphology,wound healing and transwell assays were performed to examine the effect of TFA on morphology,migration and invasion of IEC-6 cells treated with TGF-β1.In addition,immunofluorescence,real-time PCR analysis(q RT-PCR) and western blotting assays were carried out to detect the impact of TFA on EMT progress.Moreover,western blotting assay was performed to evaluate the function of TFA on the Smad and MAPK signaling pathways.Further,the role of co-treatment of TFA and si-Smad or MAPK inhibitors has been examined by q RTPCR,western blotting,morphology,wound healing andtranswell assays.RESULTS In this study,TFA promoted transforming growth factor-β1(TGF-β1)-induced(IEC-6) morphological change,migration and invasion,and increased the expression of epithelial markers and reduced the levels of mesenchymal markers,along with the inactivation of Smad and MAPK signaling pathways.Moreover,we revealed that si-Smad and MAPK inhibitors effectively attenuated TGF-β1-induced EMT in IEC-6 cells.Importantly,co-treatment of TFA and si-Smad or MAPK inhibitors had better inhibitory effects on TGF-β1-induced EMT in IEC-6 cells than either one of them.CONCLUSION These findings could provide new insight into the molecular mechanisms of TFA on TGF-β1-induced EMT in IEC-6 cells and TFA is expected to advance as a new therapy to treat CD intestinal fibrosis.展开更多
Tongluojiunao (TLJN) is an herbal medicine consisting of two main components, geniposide and ginsenoside Rg1. TLJN has been shown to protect primary cultured hippocampal neurons. How-ever, its mechanism of action re...Tongluojiunao (TLJN) is an herbal medicine consisting of two main components, geniposide and ginsenoside Rg1. TLJN has been shown to protect primary cultured hippocampal neurons. How-ever, its mechanism of action remains unclear. In the present study, primary cultured hippocampal neurons treated with Aβ1-42 (10 μmol/L) signiifcantly increased the release of lactate dehydroge-nase, which was markedly reduced by TLJN (2 μL/mL), speciifcally by the component geniposide (26 μmol/L), but not ginsenoside Rg1 (2.5 μmol/L). hTe estrogen receptor inhibitor, ICI182780 (1 μmol/L), did not block TLJN-or geniposide-mediated decrease of lactate dehydrogenase under Aβ1-42-exposed conditions. However, the phosphatidyl inositol 3-kinase or mitogen-activated protein kinase pathway inhibitor, LY294002 (50 μmol/L) or U0126 (10 μmol/L), respectively blo cked the decrease of lactate dehydrogenase mediated by TLJN or geniposide. hTerefore, these results suggest that the non-classical estrogen pathway (i.e., phosphatidyl inositol 3-kinase or mitogen-activated protein kinase) is involved in the neuroprotective effect of TLJN, speciifcally its component, geniposide, against Aβ1-42-mediated cell death in primary cultured hippocampal neurons.展开更多
The endothelial-to-mesenchymal transition(End MT) in endothelial cells contributes to the development of cardiac fibrosis,ultimately leading to cardiac remodeling.In this study,the effects and molecular mechanisms o...The endothelial-to-mesenchymal transition(End MT) in endothelial cells contributes to the development of cardiac fibrosis,ultimately leading to cardiac remodeling.In this study,the effects and molecular mechanisms of celastrol(CEL) on transforming growth factor-β1(TGF-β1)-induced End MT in human umbilical vein endothelial(HUVEC-12) cells were investigated.The presented data demonstrated that CEL significantly blocked the morphology change of HUVEC-12 cells induced by TGF-β1 without cell cytotoxicity.In accordance with these findings,CEL blocked TGF-β1-induced EndM T as evidenced by the inhibition of the mesenchymal markers,including collagen Ⅰ,Ⅲ,α-SMA,fibronectin m RNA expression,and the increase in the m RNA expression of endothelial cell marker CD31.These changes were also confirmed by double immunofluorescence staining of CD31 and vimentin.The in vitro scratch assay showed that CEL inhibited the migration capacity of the transitioned endothelial cells induced by TGF-β1.Further experiments showed that the beneficial effect of CEL on blocking the End MT in HUVEC-12 cells was associated with the suppression of the TGF-β1/Smads signalling pathway,which was also confirmed by the inhibition of its downstream transcription factor snail1,twist1,twist2,ZEB1 and ZEB2.These results indicate that CEL blocks TGF-β1-induced End MT through TGF-β1/Smads signalling pathway and suggest that it may be a feasible therapy for cardiac fibrosis diseases.展开更多
The mitogen-activated protein kinase(MAPK) signaling pathway plays an important role in the regulation of cell growth, proliferation, differentiation, transformation and death. Mitogen-activated protein kinase phosp...The mitogen-activated protein kinase(MAPK) signaling pathway plays an important role in the regulation of cell growth, proliferation, differentiation, transformation and death. Mitogen-activated protein kinase phosphatase 1(MKP1) has an inhibitory effect on the p38 MAPK and JNK pathways, but it is unknown whether it plays a role in Aβ-induced oxidative stress and neuronal inflammation. In this study, PC12 cells were infected with MKP1 sh RNA, MKP1 lentivirus or control lentivirus for 12 hours, and then treated with 0.1, 1, 10 or 100 μM amyloid beta 42(Aβ42). The cell survival rate was measured using the cell counting kit-8 assay. MKP1, tumor necrosis factor-alpha(TNF-α) and interleukin-1β(IL-1β) m RNA expression levels were analyzed using quantitative real time-polymerase chain reaction. MKP1 and phospho-c-Jun N-terminal kinase(JNK) expression levels were assessed using western blot assay. Reactive oxygen species(ROS) levels were detected using 2′,7′-dichlorofluorescein diacetate. Mitochondrial membrane potential was measured using flow cytometry. Superoxide dismutase activity and malondialdehyde levels were evaluated using the colorimetric method. Lactate dehydrogenase activity was measured using a microplate reader. Caspase-3 expression levels were assessed by enzyme-linked immunosorbent assay. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase d UTP nick end labeling method. MKP1 overexpression inhibited Aβ-induced JNK phosphorylation and the increase in ROS levels. It also suppressed the Aβ-induced increase in TNF-α and IL-1β levels as well as apoptosis in PC12 cells. In contrast, MKP1 knockdown by RNA interference aggravated Aβ-induced oxidative stress, inflammation and cell damage in PC12 cells. Furthermore, the JNK-specific inhibitor SP600125 abolished this effect of MKP1 knockdown on Aβ-induced neurotoxicity. Collectively, these results show that MKP1 mitigates Aβ-induced apoptosis, oxidative stress and neuroinflammation by inhibiting the JNK signaling pathway, thereby playing a neuroprotective role.展开更多
Throughout the globe,diabetes mellitus(DM) is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and af...Throughout the globe,diabetes mellitus(DM) is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin(m TOR) is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1(m TORC1) and m TOR Complex 2(m TORC2) and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase(PI 3-K),protein kinase B(Akt),AMP activated protein kinase(AMPK),silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae)(SIRT1),Wnt1 inducible signaling pathway protein 1(WISP1),and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM.展开更多
Objective:To explore whether acupuncture combined with moxibustion could inhibit epithelialmesenchymal transition in Crohn’s disease by affecting the transforming growth factorβ1(TGF-β1)/Smad3/Snail pathway.Methods...Objective:To explore whether acupuncture combined with moxibustion could inhibit epithelialmesenchymal transition in Crohn’s disease by affecting the transforming growth factorβ1(TGF-β1)/Smad3/Snail pathway.Methods:Sixty-three patients with Crohn’s disease were randomly divided into an observation group(31 cases)receiving moxibustion at 43℃ combined with acupuncture,and a control group(32 cases)receiving moxibustion at 37℃combined with sham acupuncture using a random number table.Patients were treated for12 weeks.Crohn’s Disease Activity Index(CDAI)was used to evaluate disease activity.Hematoxylin-eosin staining and transmission electron microscopy were utilized to observe the morphological and ultrastructural changes.Immunohistochemistry was used to detect the expression of transforming growth factorβ1(TGF-β1),TβR1,TβR2,Smad3,Snail,E-cadherin and fibronectin in intestinal mucosal tissues.Results:The decrease of the CDAI score,morphological and ultrastructural changes were more significant in observation group.The expression levels of TGF-β1,TβR2,Smad3,and Snail in the observation group were significantly lower than those before the treatment(P<0.05 or P<0.01).After treatment,the expression levels of TGF-β1,TβR2,and Snail in the observation group were significantly lower than those in the control group(all P<0.05);compared with the control group,the expression of fibronectin in the observation group was significantly decreased,and the expression of E-cadherin was significantly increased(all P<0.05).Conclusions:Moxibustion at 43℃combined with acupuncture may suppress TGF-β1/Smad3/Snail pathway-mediated epithelial-mesenchymal transition of intestinal epithelial cells in Crohn’s disease patients by inhibiting the expression levels of TGF-β1,TβR2,Smad3,and Snail.(Registration No.ChiCTR-IIR-16007751).展开更多
Sphingosine-1-phosphate receptor 1 (S1PR1), a G protein-coupled recep (GPCR). controls vasct stability by stabilizing vascular endothelial (VE)-cadherin junctional localization and inhibiting vascular endothelia...Sphingosine-1-phosphate receptor 1 (S1PR1), a G protein-coupled recep (GPCR). controls vasct stability by stabilizing vascular endothelial (VE)-cadherin junctional localization and inhibiting vascular endothelial growth factor receptor 2(VEGFR2) signaling. However, the molecular mechanisms that link S1PR1 signaling to intracellular effectors remain unknown.In this study,we demonstrate that the heterotrimeric G protein subfamily member Gαs, encoded by GNAS,acts as a relay mediator of S1PR1 signaling to control vascular integrity by stabilizing VE-cadherin at endothelial junctions. The endothelial cell -spectific deletion of Gαs in mice causes early embryonic lethality with massive hemorrhage and a disorganized Vaseuiature.The immunostaining results revealed that Gαs deletion remarkably reduces the junctional localization of VE-cadherin, whereas the mull cell coverage of the vessels is not impaired.In addition, we found-that Gαs depletion blocks the S1PR1-activation induced VE-cadherin stabilization at junctons,supporting that Gαs acts downstream of S1PR1 signaling ThuS, our results demonstrate that Gαs is an essential mediator to relay S1PR1 signaling and maintain vascular integrity.展开更多
Objective To study the role and mechanism of sphingosine-phosphate(S1P)/sphingosine-1-phosphate receptor 1(S1P1)signal pathway during post conditioning of hypertrophic cardiomyocytes.Methods Neonatal rat cardiomyocyte...Objective To study the role and mechanism of sphingosine-phosphate(S1P)/sphingosine-1-phosphate receptor 1(S1P1)signal pathway during post conditioning of hypertrophic cardiomyocytes.Methods Neonatal rat cardiomyocytes were isolated and cultured,then stimulated by norepinephrine(NE)to induce cardiomyocytes hypertrophy.Using tri-gas incubator to create展开更多
Objective: To evaluate the effects of Celastrus Orbiculatus extracts(COE) on metastasis in hypoxiainduced hepatocellular carcinoma cells(Hep G2) and to explore the underlying molecular mechanisms. Methods:The effect o...Objective: To evaluate the effects of Celastrus Orbiculatus extracts(COE) on metastasis in hypoxiainduced hepatocellular carcinoma cells(Hep G2) and to explore the underlying molecular mechanisms. Methods:The effect of COE(160, 200 and 240 μg/mL) on cell viability, scratch-wound, invasion and migration were studied by 3-4,5-dimethyl-2-thiazolyl-2,5-diphenyl-2-H-tetrazolium bromide(MTT), scratch-wound and transwell assays, respectively. Co Cl2 was used to establish a hypoxia model in vitro. Effects of COE on the expressions of E-cadherin, vimentin and N-cadherin were investigated with Western blot and immuno?uorescence analysis,respectively. Results: COE inhibited proliferation and metastasis of hypoxia-induced hepatocellular carcinoma cells in a dose-dependent manner(P<0.01). Furthermore, the expression of epithelial-mesenchymal transition(EMT) related markers were also remarkably suppressed in a dose-dependent manner(P<0.01). In addition, the upstream signaling pathways, including the hypoxia-inducible factor 1α(Hif-1α) and Twist1 were suppressed by COE. Additionally, the Hif-1α inhibitor 3-5'-hydroxymethyl-2'-furyl)-1-benzylindazole(YC-1), potently suppressed cell invasion and migration as well as expression of EMT in hypoxia-induced Hep G2 cells. Similarly, the combined treatment with COE and YC-1 showed a synergistic effect(P<0.01) compared with the treatment with COE or YC-1 alone in hypoxia-induced Hep G2 cells. Conclusions: COE signi?cantly inhibited the tumor metastasis and EMT by suppressing Hif-1α/Twist1 signaling pathway in hypoxia-induced Hep G2 cell. Thus, COE might have potential effect to inhibit the progression of Hep G2 in the context of tumor hypoxia.展开更多
The APPswe plasmid was transfected into the neuroblastoma cell line SH-SY5Y to establish a cell model of Alzheimer's disease. Graded concentration and time course experiments demonstrate that curcumin significantly u...The APPswe plasmid was transfected into the neuroblastoma cell line SH-SY5Y to establish a cell model of Alzheimer's disease. Graded concentration and time course experiments demonstrate that curcumin significantly upregulates phosphatidylinositol 3-kinase (PI3K), Akt, nuclear factor E2-related factor-2 (Nrf2), heme oxygenase 1 and ferritin expression, and that it significantly downregulates heme oxygenase 2, reactive oxygen species and amyloid-beta 40/42 expression. These effects of curcumin on PI3K, Akt and Nrf2 were blocked by LY294002 (PI3k inhibitor) and NF-E2-related factor-2 siRNA. The results indicate that the cytoprotection conferred by curcumin on APPswe transfected SH-SY5Y cells is mediated by its ability to regulate the balance between heme oxygenase 1 and 2 via the PI3K/Akt/Nrf2 intracellular signaling pathway.展开更多
A preliminary study on the interaction of G protein (guanine triphosphate binding pro- tein) b1g2 subunits and their coupled components in cell signal transduction was conducted in vitro. The insect cell lines, Sf9 (S...A preliminary study on the interaction of G protein (guanine triphosphate binding pro- tein) b1g2 subunits and their coupled components in cell signal transduction was conducted in vitro. The insect cell lines, Sf9 (Spodoptera frugiperda) and H5 (Trichoplusia ni ) were used to express the recombinant protein Gb1g2. The cell membrane containing Gb1g2 was isolated through affinity chromatography column with Ni-NTA agarose by FPLC method, and the highly purified protein was obtained. The adenylyl cyclase 2 (AC2) activity assay showed that the purified Gb1g2 could signifi-cantly stimulate AC2 activity. The interaction of b1g2 subunits of G protein with the cytoplasmic tail of various mammalian adenylyl cyclases was monitored by BIAcore technology using NTA sensor chip, which relies on the phenomenon of surface plasmon resonance (SPR). The experiments showed the direct binding of Gb1g2 to the cytoplasmic tail C2 domain of AC2. The specific binding domain of AC2 with Gb1g2 was the same as AC2 activity domain which was stimulated by Gb1g2.展开更多
基金supported by the National Natural Science Foundation of China(Youth Science Fund Project),No.81901292(to GC)the National Key Research and Development Program of China,No.2021YFC2502100(to GC)the National Natural Science Foundation of China,No.82071183(to ZZ).
文摘Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic function.Increasing amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of cancers.These findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative diseases.Through a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.
基金Supported by the Natural Science Foundation of Jiangsu Province,China,No.BK2016157the National Natural Science Foundation of China,No.81673973+1 种基金Phase Ⅱ Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,No.035062002003Developing Program for Highlevel Academic Talent in Jiangsu Hospital of TCM,No.y2018rc16
文摘AIM To explore the role and mechanism of total flavone of Abelmoschus manihot(TFA) on epithelial-mesenchymal transition(EMT) progress of Crohn's disease(CD) intestinal fibrosis.METHODS First,CCK-8 assay was performed to assess TFA on the viability of intestinal epithelial(IEC-6) cells and select the optimal concentrations of TFA for our further studies.Then cell morphology,wound healing and transwell assays were performed to examine the effect of TFA on morphology,migration and invasion of IEC-6 cells treated with TGF-β1.In addition,immunofluorescence,real-time PCR analysis(q RT-PCR) and western blotting assays were carried out to detect the impact of TFA on EMT progress.Moreover,western blotting assay was performed to evaluate the function of TFA on the Smad and MAPK signaling pathways.Further,the role of co-treatment of TFA and si-Smad or MAPK inhibitors has been examined by q RTPCR,western blotting,morphology,wound healing andtranswell assays.RESULTS In this study,TFA promoted transforming growth factor-β1(TGF-β1)-induced(IEC-6) morphological change,migration and invasion,and increased the expression of epithelial markers and reduced the levels of mesenchymal markers,along with the inactivation of Smad and MAPK signaling pathways.Moreover,we revealed that si-Smad and MAPK inhibitors effectively attenuated TGF-β1-induced EMT in IEC-6 cells.Importantly,co-treatment of TFA and si-Smad or MAPK inhibitors had better inhibitory effects on TGF-β1-induced EMT in IEC-6 cells than either one of them.CONCLUSION These findings could provide new insight into the molecular mechanisms of TFA on TGF-β1-induced EMT in IEC-6 cells and TFA is expected to advance as a new therapy to treat CD intestinal fibrosis.
基金supported by the National Natural Science Foundation of China No.81072901the New Teacher Fund for Doctor Station,Ministry of Education,No.20120013110013+1 种基金grants from the Nautical Traditional Chinese Medicine Discipline,No.522/0100604054grants from the Nautical Traditional Chinese Medicine Collaborative Innovation Center,No.522/0100604299
文摘Tongluojiunao (TLJN) is an herbal medicine consisting of two main components, geniposide and ginsenoside Rg1. TLJN has been shown to protect primary cultured hippocampal neurons. How-ever, its mechanism of action remains unclear. In the present study, primary cultured hippocampal neurons treated with Aβ1-42 (10 μmol/L) signiifcantly increased the release of lactate dehydroge-nase, which was markedly reduced by TLJN (2 μL/mL), speciifcally by the component geniposide (26 μmol/L), but not ginsenoside Rg1 (2.5 μmol/L). hTe estrogen receptor inhibitor, ICI182780 (1 μmol/L), did not block TLJN-or geniposide-mediated decrease of lactate dehydrogenase under Aβ1-42-exposed conditions. However, the phosphatidyl inositol 3-kinase or mitogen-activated protein kinase pathway inhibitor, LY294002 (50 μmol/L) or U0126 (10 μmol/L), respectively blo cked the decrease of lactate dehydrogenase mediated by TLJN or geniposide. hTerefore, these results suggest that the non-classical estrogen pathway (i.e., phosphatidyl inositol 3-kinase or mitogen-activated protein kinase) is involved in the neuroprotective effect of TLJN, speciifcally its component, geniposide, against Aβ1-42-mediated cell death in primary cultured hippocampal neurons.
文摘The endothelial-to-mesenchymal transition(End MT) in endothelial cells contributes to the development of cardiac fibrosis,ultimately leading to cardiac remodeling.In this study,the effects and molecular mechanisms of celastrol(CEL) on transforming growth factor-β1(TGF-β1)-induced End MT in human umbilical vein endothelial(HUVEC-12) cells were investigated.The presented data demonstrated that CEL significantly blocked the morphology change of HUVEC-12 cells induced by TGF-β1 without cell cytotoxicity.In accordance with these findings,CEL blocked TGF-β1-induced EndM T as evidenced by the inhibition of the mesenchymal markers,including collagen Ⅰ,Ⅲ,α-SMA,fibronectin m RNA expression,and the increase in the m RNA expression of endothelial cell marker CD31.These changes were also confirmed by double immunofluorescence staining of CD31 and vimentin.The in vitro scratch assay showed that CEL inhibited the migration capacity of the transitioned endothelial cells induced by TGF-β1.Further experiments showed that the beneficial effect of CEL on blocking the End MT in HUVEC-12 cells was associated with the suppression of the TGF-β1/Smads signalling pathway,which was also confirmed by the inhibition of its downstream transcription factor snail1,twist1,twist2,ZEB1 and ZEB2.These results indicate that CEL blocks TGF-β1-induced End MT through TGF-β1/Smads signalling pathway and suggest that it may be a feasible therapy for cardiac fibrosis diseases.
文摘The mitogen-activated protein kinase(MAPK) signaling pathway plays an important role in the regulation of cell growth, proliferation, differentiation, transformation and death. Mitogen-activated protein kinase phosphatase 1(MKP1) has an inhibitory effect on the p38 MAPK and JNK pathways, but it is unknown whether it plays a role in Aβ-induced oxidative stress and neuronal inflammation. In this study, PC12 cells were infected with MKP1 sh RNA, MKP1 lentivirus or control lentivirus for 12 hours, and then treated with 0.1, 1, 10 or 100 μM amyloid beta 42(Aβ42). The cell survival rate was measured using the cell counting kit-8 assay. MKP1, tumor necrosis factor-alpha(TNF-α) and interleukin-1β(IL-1β) m RNA expression levels were analyzed using quantitative real time-polymerase chain reaction. MKP1 and phospho-c-Jun N-terminal kinase(JNK) expression levels were assessed using western blot assay. Reactive oxygen species(ROS) levels were detected using 2′,7′-dichlorofluorescein diacetate. Mitochondrial membrane potential was measured using flow cytometry. Superoxide dismutase activity and malondialdehyde levels were evaluated using the colorimetric method. Lactate dehydrogenase activity was measured using a microplate reader. Caspase-3 expression levels were assessed by enzyme-linked immunosorbent assay. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase d UTP nick end labeling method. MKP1 overexpression inhibited Aβ-induced JNK phosphorylation and the increase in ROS levels. It also suppressed the Aβ-induced increase in TNF-α and IL-1β levels as well as apoptosis in PC12 cells. In contrast, MKP1 knockdown by RNA interference aggravated Aβ-induced oxidative stress, inflammation and cell damage in PC12 cells. Furthermore, the JNK-specific inhibitor SP600125 abolished this effect of MKP1 knockdown on Aβ-induced neurotoxicity. Collectively, these results show that MKP1 mitigates Aβ-induced apoptosis, oxidative stress and neuroinflammation by inhibiting the JNK signaling pathway, thereby playing a neuroprotective role.
基金supported by American Diabetes Association,American Heart Association,NIH NIEHS,NIH NIA,NIH NINDS,and NIH ARRA
文摘Throughout the globe,diabetes mellitus(DM) is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin(m TOR) is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1(m TORC1) and m TOR Complex 2(m TORC2) and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase(PI 3-K),protein kinase B(Akt),AMP activated protein kinase(AMPK),silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae)(SIRT1),Wnt1 inducible signaling pathway protein 1(WISP1),and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM.
基金Supported by the National Natural Science Foundation of China(Nos.81674069 and 81473757)。
文摘Objective:To explore whether acupuncture combined with moxibustion could inhibit epithelialmesenchymal transition in Crohn’s disease by affecting the transforming growth factorβ1(TGF-β1)/Smad3/Snail pathway.Methods:Sixty-three patients with Crohn’s disease were randomly divided into an observation group(31 cases)receiving moxibustion at 43℃ combined with acupuncture,and a control group(32 cases)receiving moxibustion at 37℃combined with sham acupuncture using a random number table.Patients were treated for12 weeks.Crohn’s Disease Activity Index(CDAI)was used to evaluate disease activity.Hematoxylin-eosin staining and transmission electron microscopy were utilized to observe the morphological and ultrastructural changes.Immunohistochemistry was used to detect the expression of transforming growth factorβ1(TGF-β1),TβR1,TβR2,Smad3,Snail,E-cadherin and fibronectin in intestinal mucosal tissues.Results:The decrease of the CDAI score,morphological and ultrastructural changes were more significant in observation group.The expression levels of TGF-β1,TβR2,Smad3,and Snail in the observation group were significantly lower than those before the treatment(P<0.05 or P<0.01).After treatment,the expression levels of TGF-β1,TβR2,and Snail in the observation group were significantly lower than those in the control group(all P<0.05);compared with the control group,the expression of fibronectin in the observation group was significantly decreased,and the expression of E-cadherin was significantly increased(all P<0.05).Conclusions:Moxibustion at 43℃combined with acupuncture may suppress TGF-β1/Smad3/Snail pathway-mediated epithelial-mesenchymal transition of intestinal epithelial cells in Crohn’s disease patients by inhibiting the expression levels of TGF-β1,TβR2,Smad3,and Snail.(Registration No.ChiCTR-IIR-16007751).
基金partially supported by the grants from the Ministry of Science & Technology-China (Nos.2014CB964600 and 2012CB966800)the National Science Foundation of China (Nos. 31301125 and 31071283)+2 种基金Shenzhen Peacock Plan (No. KQCX20130628112914292)Shenzhen Key Laboratory for Molecular Biology of Neural Development (No. ZDSY20120617112838879)SIAT Innovation Program for Excellent Young Researchers (No. 201404)
文摘Sphingosine-1-phosphate receptor 1 (S1PR1), a G protein-coupled recep (GPCR). controls vasct stability by stabilizing vascular endothelial (VE)-cadherin junctional localization and inhibiting vascular endothelial growth factor receptor 2(VEGFR2) signaling. However, the molecular mechanisms that link S1PR1 signaling to intracellular effectors remain unknown.In this study,we demonstrate that the heterotrimeric G protein subfamily member Gαs, encoded by GNAS,acts as a relay mediator of S1PR1 signaling to control vascular integrity by stabilizing VE-cadherin at endothelial junctions. The endothelial cell -spectific deletion of Gαs in mice causes early embryonic lethality with massive hemorrhage and a disorganized Vaseuiature.The immunostaining results revealed that Gαs deletion remarkably reduces the junctional localization of VE-cadherin, whereas the mull cell coverage of the vessels is not impaired.In addition, we found-that Gαs depletion blocks the S1PR1-activation induced VE-cadherin stabilization at junctons,supporting that Gαs acts downstream of S1PR1 signaling ThuS, our results demonstrate that Gαs is an essential mediator to relay S1PR1 signaling and maintain vascular integrity.
文摘Objective To study the role and mechanism of sphingosine-phosphate(S1P)/sphingosine-1-phosphate receptor 1(S1P1)signal pathway during post conditioning of hypertrophic cardiomyocytes.Methods Neonatal rat cardiomyocytes were isolated and cultured,then stimulated by norepinephrine(NE)to induce cardiomyocytes hypertrophy.Using tri-gas incubator to create
基金Supported by the National Natural Science Foundation of China(No.81403232 and No.81573656)Natural Science Foundation of Jiangsu Province(No.BK20171290 and No.BK2012686)Doctoral Fund of Ministry of Education of China(No.20133250120003)
文摘Objective: To evaluate the effects of Celastrus Orbiculatus extracts(COE) on metastasis in hypoxiainduced hepatocellular carcinoma cells(Hep G2) and to explore the underlying molecular mechanisms. Methods:The effect of COE(160, 200 and 240 μg/mL) on cell viability, scratch-wound, invasion and migration were studied by 3-4,5-dimethyl-2-thiazolyl-2,5-diphenyl-2-H-tetrazolium bromide(MTT), scratch-wound and transwell assays, respectively. Co Cl2 was used to establish a hypoxia model in vitro. Effects of COE on the expressions of E-cadherin, vimentin and N-cadherin were investigated with Western blot and immuno?uorescence analysis,respectively. Results: COE inhibited proliferation and metastasis of hypoxia-induced hepatocellular carcinoma cells in a dose-dependent manner(P<0.01). Furthermore, the expression of epithelial-mesenchymal transition(EMT) related markers were also remarkably suppressed in a dose-dependent manner(P<0.01). In addition, the upstream signaling pathways, including the hypoxia-inducible factor 1α(Hif-1α) and Twist1 were suppressed by COE. Additionally, the Hif-1α inhibitor 3-5'-hydroxymethyl-2'-furyl)-1-benzylindazole(YC-1), potently suppressed cell invasion and migration as well as expression of EMT in hypoxia-induced Hep G2 cells. Similarly, the combined treatment with COE and YC-1 showed a synergistic effect(P<0.01) compared with the treatment with COE or YC-1 alone in hypoxia-induced Hep G2 cells. Conclusions: COE signi?cantly inhibited the tumor metastasis and EMT by suppressing Hif-1α/Twist1 signaling pathway in hypoxia-induced Hep G2 cell. Thus, COE might have potential effect to inhibit the progression of Hep G2 in the context of tumor hypoxia.
基金supported by the National Science Foundation of China,No.30973154the Science Foundation of Chongqing,No.2009BB5270the Chongqing Municipal Education Commission Foundation,No.KJ090301
文摘The APPswe plasmid was transfected into the neuroblastoma cell line SH-SY5Y to establish a cell model of Alzheimer's disease. Graded concentration and time course experiments demonstrate that curcumin significantly upregulates phosphatidylinositol 3-kinase (PI3K), Akt, nuclear factor E2-related factor-2 (Nrf2), heme oxygenase 1 and ferritin expression, and that it significantly downregulates heme oxygenase 2, reactive oxygen species and amyloid-beta 40/42 expression. These effects of curcumin on PI3K, Akt and Nrf2 were blocked by LY294002 (PI3k inhibitor) and NF-E2-related factor-2 siRNA. The results indicate that the cytoprotection conferred by curcumin on APPswe transfected SH-SY5Y cells is mediated by its ability to regulate the balance between heme oxygenase 1 and 2 via the PI3K/Akt/Nrf2 intracellular signaling pathway.
基金This work was sup-ported by the National Natural Science Foundation of China (Grant No. 30170615) and National Major Basis Study Develop-mental Plan 973 Project (TG2000016208).
文摘A preliminary study on the interaction of G protein (guanine triphosphate binding pro- tein) b1g2 subunits and their coupled components in cell signal transduction was conducted in vitro. The insect cell lines, Sf9 (Spodoptera frugiperda) and H5 (Trichoplusia ni ) were used to express the recombinant protein Gb1g2. The cell membrane containing Gb1g2 was isolated through affinity chromatography column with Ni-NTA agarose by FPLC method, and the highly purified protein was obtained. The adenylyl cyclase 2 (AC2) activity assay showed that the purified Gb1g2 could signifi-cantly stimulate AC2 activity. The interaction of b1g2 subunits of G protein with the cytoplasmic tail of various mammalian adenylyl cyclases was monitored by BIAcore technology using NTA sensor chip, which relies on the phenomenon of surface plasmon resonance (SPR). The experiments showed the direct binding of Gb1g2 to the cytoplasmic tail C2 domain of AC2. The specific binding domain of AC2 with Gb1g2 was the same as AC2 activity domain which was stimulated by Gb1g2.