Protective effect of catalpol on myocardium was studied in relation to endothelial progenitor cells, Notch1 signaling pathway and angiogenesis in rats with isoprenaline (INN)-induced acute myocardial infarcts. To anal...Protective effect of catalpol on myocardium was studied in relation to endothelial progenitor cells, Notch1 signaling pathway and angiogenesis in rats with isoprenaline (INN)-induced acute myocardial infarcts. To analyze the pathological status and impact of catalpol on the rats, 3 weeks after intragastric gavage, the animals were verified for myocardial infarcts with electrocardiogram and measured for enzyme activity of lactate dehydrogenase (LDH), malondialdehyde (MDA), creatine kinase (CK) and superoxide dismutase (SOD) in myocardium, and further analyzed using HE and TTC staining, as well as visual examination of infarct area. Flow cytometry study of endothelial progenitor cells (EPCs) indicated that the EPCs were mobilized during infarction. The roles of Notch1 signaling pathway in angiogenesis of the infracted animals were studied using immunohistochemistry analysis of RBPjκ and Western blot analysis of Notch1 and Jagged1. Our results obtained from the rats treated with catalpol, positive drug and control showed that catalpol could protect rats from infarction probably by mobilization of EPCs and activation of Notch1 signaling pathway.展开更多
Objective： To examine the effects of brucine on the invasion, migration and bone resorption of receptor activator of nuclear factor-kappa B ligand（RANKL）-induced osteoclastogenesis. Methods： The osteoclastogenesis...Objective： To examine the effects of brucine on the invasion, migration and bone resorption of receptor activator of nuclear factor-kappa B ligand（RANKL）-induced osteoclastogenesis. Methods： The osteoclastogenesis model was builded by co-culturing human breast tumor MDA-MB-231 and mouse RAW264.7 macrophages cells. RANKL（50 ng/m L） and macrophage-colony stimulating factor（50 ng/m L） were added to this system, followed by treatment with brucine（0.02, 0.04 and 0.08 mmol/L）, or 10 μmol/L zoledronic acid as positive control. The migration and bone resorption were measured by transwell assay and in vitro bone resorption assay. The protein expressions of Jagged1 and Notch1 were investigated by Western blot. The expressions of transforming growth factor-β1（TGF-β1）, nuclear factor-kappa B（NF-κB） and Hes1 were determined by enzyme-linked immunosorbent assay. Results： Compared with the model group, brucine led to a dose-dependent decrease on migration of MDA-MB-231 cells, inhibited RANKL-induced osteoclastogenesis and bone resorption of RAW264.7 cells（P 〈0.01）. Furthermore, brucine decreased the protein levels of Jagged1 and Notch1 in MDA-MB-231 cells and RAW264.7 cells co-cultured system as well as the expressions of TGF-β1, NF-κB and Hes1（P〈0.05 or P〈0.01）. Conclusion： Brucine may inhibit osteoclastogenesis by suppressing Jagged1/Notch1 signaling pathways.展开更多
Adult olfactory neurogenesis plays critical roles in maintaining olfactory functions.Newly-generated neurons in the subventricular zone migrate to the olfactory bulb(OB) and determine olfactory discrimination,but the ...Adult olfactory neurogenesis plays critical roles in maintaining olfactory functions.Newly-generated neurons in the subventricular zone migrate to the olfactory bulb(OB) and determine olfactory discrimination,but the mechanisms underlying the regulation of olfactory neurogenesis remain unclear.Our previous study indicated the potential of APPL2(adaptor protein,phosphotyrosine interacting with PH domain and leucine zipper 2) as a modulating factor for neurogenesis in the adult olfactory system.In the present study,we report how APPL2 affects neurogenesis in the OB and thereby mediates olfactory discrimination by using both in vitro neural stem cells(NSCs) and an in vivo animal model-APPL2 transgenic(Tg) mice.In the in vitro study,we found that APPL2 overexpression resulted in NSCs switching from neuronal differentiation to gliogenesis while APPL2 knockdown promoted neurogenesis.In the in vivo study,APPL2 Tg mice had a higher population of glial cells and dampened neuronal production in the olfactory system,including the corpus callosum,OB,and rostral migratory stream.Adult APPL2 Tg mice displayed impaired performance in olfactory discrimination tests compared with wild-type mice.Furthermore,we found that an interaction of APPL2 with Notch1 contributed to the roles of APPL2 in modulating the neurogenic lineage-switching and olfactory behaviors.In conclusion,APPL2 controls olfactory discrimination by switching the fate choice of NSCs via interaction with Notch1 signaling.展开更多
Hypoxia is beneficial for the differentiation of stem cells transplanted for myocardial injury,but mechanisms underlying this benefit remain unsolved. Here, we report the impact of hypoxia-induced Jagged1 expression i...Hypoxia is beneficial for the differentiation of stem cells transplanted for myocardial injury,but mechanisms underlying this benefit remain unsolved. Here, we report the impact of hypoxia-induced Jagged1 expression in cardiomyocytes(CMs) for driving the differentiation of cardiac stem cells(CSCs).Forced hypoxia-inducible factor 1α(HIF-1α) expression and physical hypoxia(5% O_2) treatment could induce Jagged1 expression in neonatal rat CMs. Pharmacological inhibition of HIF-1α by YC-1 attenuated hypoxia-promoted Jagged1 expression in CMs. An ERK inhibitor(PD98059), but not inhibitors of JNK(SP600125), Notch(DAPT), NF-κB(PTDC), JAK(AG490), or STAT3(Stattic) suppressed hypoxiainduced Jagged1 protein expression in CMs. c-Kit^+ CSCs isolated from neonatal rat hearts using a magnetic-activated cell sorting method expressed GATA4, SM22α or vWF, but not Nkx2.5 and cTnI.Moreover, 87.3% of freshly isolated CSCs displayed Notch1 receptor expression. Direct co-culture of CMs with BrdU-labeled CSCs enhanced CSCs differentiation, as evidenced by an increased number of BrdU^+/Nkx2.5^+ cells, while intermittent hypoxia for 21 days promoted co-culture-triggered differentiation of CSCs into CM-like cells. Notably, YC-1 and DAPT attenuated hypoxia-induced differentiation.Our results suggest that hypoxia induces Jagged1 expression in CMs primarily through ERK signaling,and facilitates early cardiac lineage differentiation of CSCs in CM/CSC co-cultures via HIF-1α/Jagged1/Notch signaling.展开更多
目的:观察白藜芦醇(Res)对急性T淋巴细胞白血病(T-ALL)小鼠的影响,并进一步探讨其对Notch1信号通路的作用机制。方法:将25只6-8周龄雌性C57BL/6小鼠随机分为正常对照组、T-ALL组和Res组,其中Res组又进一步分为low-Res(L-Res)、middle-Re...目的:观察白藜芦醇(Res)对急性T淋巴细胞白血病(T-ALL)小鼠的影响,并进一步探讨其对Notch1信号通路的作用机制。方法:将25只6-8周龄雌性C57BL/6小鼠随机分为正常对照组、T-ALL组和Res组,其中Res组又进一步分为low-Res(L-Res)、middle-Res(M-Res)和high-Res(H-Res)3个浓度给药组。应用流式细胞术和瑞氏-吉姆萨染色法检测外周血及脾细胞悬液中白血病细胞百分比,HE染色法观察脾脏和骨髓组织病理形态,RT-q PCR法检测脾脏组织中Notch1、Hes-1、c-Myc、mi R-19b和PTEN m RNA表达水平,Western blot法检测Notch1、Hes-1、c-Myc、p-PTEN和PTEN蛋白表达水平。结果:与对照组相比,T-ALL组小鼠外周血中白血病细胞明显增多,脾脏及骨髓组织中白血病细胞弥漫性浸润,脾脏中Notch1、Hes-1、c-Myc、mi R-19b m RNA表达水平和Notch1、Hes-1、c-Myc蛋白表达水平均明显增高(P<0.01),PTEN m RNA及其蛋白水平显著降低(P<0.01),经白藜芦醇处理后,H-Res组以上各项指标较T-ALL组均获得逆转。结论:白藜芦醇具有抗小鼠T-ALL的作用,其机制可能通过抑制Notch1信号通路发挥作用。展开更多
文摘Protective effect of catalpol on myocardium was studied in relation to endothelial progenitor cells, Notch1 signaling pathway and angiogenesis in rats with isoprenaline (INN)-induced acute myocardial infarcts. To analyze the pathological status and impact of catalpol on the rats, 3 weeks after intragastric gavage, the animals were verified for myocardial infarcts with electrocardiogram and measured for enzyme activity of lactate dehydrogenase (LDH), malondialdehyde (MDA), creatine kinase (CK) and superoxide dismutase (SOD) in myocardium, and further analyzed using HE and TTC staining, as well as visual examination of infarct area. Flow cytometry study of endothelial progenitor cells (EPCs) indicated that the EPCs were mobilized during infarction. The roles of Notch1 signaling pathway in angiogenesis of the infracted animals were studied using immunohistochemistry analysis of RBPjκ and Western blot analysis of Notch1 and Jagged1. Our results obtained from the rats treated with catalpol, positive drug and control showed that catalpol could protect rats from infarction probably by mobilization of EPCs and activation of Notch1 signaling pathway.
基金Supported by the Fifty-fifth Batch of China Post Doctoral Science Foundation(No.2014M550663)
文摘Objective： To examine the effects of brucine on the invasion, migration and bone resorption of receptor activator of nuclear factor-kappa B ligand（RANKL）-induced osteoclastogenesis. Methods： The osteoclastogenesis model was builded by co-culturing human breast tumor MDA-MB-231 and mouse RAW264.7 macrophages cells. RANKL（50 ng/m L） and macrophage-colony stimulating factor（50 ng/m L） were added to this system, followed by treatment with brucine（0.02, 0.04 and 0.08 mmol/L）, or 10 μmol/L zoledronic acid as positive control. The migration and bone resorption were measured by transwell assay and in vitro bone resorption assay. The protein expressions of Jagged1 and Notch1 were investigated by Western blot. The expressions of transforming growth factor-β1（TGF-β1）, nuclear factor-kappa B（NF-κB） and Hes1 were determined by enzyme-linked immunosorbent assay. Results： Compared with the model group, brucine led to a dose-dependent decrease on migration of MDA-MB-231 cells, inhibited RANKL-induced osteoclastogenesis and bone resorption of RAW264.7 cells（P 〈0.01）. Furthermore, brucine decreased the protein levels of Jagged1 and Notch1 in MDA-MB-231 cells and RAW264.7 cells co-cultured system as well as the expressions of TGF-β1, NF-κB and Hes1（P〈0.05 or P〈0.01）. Conclusion： Brucine may inhibit osteoclastogenesis by suppressing Jagged1/Notch1 signaling pathways.
基金supported by Areas of Excellence (AoE/P-705/16)the General Research Fund,Hong Kong SAR (GRF No.777313 M)。
文摘Adult olfactory neurogenesis plays critical roles in maintaining olfactory functions.Newly-generated neurons in the subventricular zone migrate to the olfactory bulb(OB) and determine olfactory discrimination,but the mechanisms underlying the regulation of olfactory neurogenesis remain unclear.Our previous study indicated the potential of APPL2(adaptor protein,phosphotyrosine interacting with PH domain and leucine zipper 2) as a modulating factor for neurogenesis in the adult olfactory system.In the present study,we report how APPL2 affects neurogenesis in the OB and thereby mediates olfactory discrimination by using both in vitro neural stem cells(NSCs) and an in vivo animal model-APPL2 transgenic(Tg) mice.In the in vitro study,we found that APPL2 overexpression resulted in NSCs switching from neuronal differentiation to gliogenesis while APPL2 knockdown promoted neurogenesis.In the in vivo study,APPL2 Tg mice had a higher population of glial cells and dampened neuronal production in the olfactory system,including the corpus callosum,OB,and rostral migratory stream.Adult APPL2 Tg mice displayed impaired performance in olfactory discrimination tests compared with wild-type mice.Furthermore,we found that an interaction of APPL2 with Notch1 contributed to the roles of APPL2 in modulating the neurogenic lineage-switching and olfactory behaviors.In conclusion,APPL2 controls olfactory discrimination by switching the fate choice of NSCs via interaction with Notch1 signaling.
基金supported by grants from the National Natural Science Foundation of China (Grant Nos.81170121,81460042,81541004 and 81670254)Science and Technology Project of Guangdong Province (2016A020214016)+1 种基金YangFan Plan of Guangdong Province (4YF16007G)Excellent Graduate Student Training Program of Guangdong Medical University (YS2014013)
文摘Hypoxia is beneficial for the differentiation of stem cells transplanted for myocardial injury,but mechanisms underlying this benefit remain unsolved. Here, we report the impact of hypoxia-induced Jagged1 expression in cardiomyocytes(CMs) for driving the differentiation of cardiac stem cells(CSCs).Forced hypoxia-inducible factor 1α(HIF-1α) expression and physical hypoxia(5% O_2) treatment could induce Jagged1 expression in neonatal rat CMs. Pharmacological inhibition of HIF-1α by YC-1 attenuated hypoxia-promoted Jagged1 expression in CMs. An ERK inhibitor(PD98059), but not inhibitors of JNK(SP600125), Notch(DAPT), NF-κB(PTDC), JAK(AG490), or STAT3(Stattic) suppressed hypoxiainduced Jagged1 protein expression in CMs. c-Kit^+ CSCs isolated from neonatal rat hearts using a magnetic-activated cell sorting method expressed GATA4, SM22α or vWF, but not Nkx2.5 and cTnI.Moreover, 87.3% of freshly isolated CSCs displayed Notch1 receptor expression. Direct co-culture of CMs with BrdU-labeled CSCs enhanced CSCs differentiation, as evidenced by an increased number of BrdU^+/Nkx2.5^+ cells, while intermittent hypoxia for 21 days promoted co-culture-triggered differentiation of CSCs into CM-like cells. Notably, YC-1 and DAPT attenuated hypoxia-induced differentiation.Our results suggest that hypoxia induces Jagged1 expression in CMs primarily through ERK signaling,and facilitates early cardiac lineage differentiation of CSCs in CM/CSC co-cultures via HIF-1α/Jagged1/Notch signaling.
文摘目的:观察白藜芦醇(Res)对急性T淋巴细胞白血病(T-ALL)小鼠的影响,并进一步探讨其对Notch1信号通路的作用机制。方法:将25只6-8周龄雌性C57BL/6小鼠随机分为正常对照组、T-ALL组和Res组,其中Res组又进一步分为low-Res(L-Res)、middle-Res(M-Res)和high-Res(H-Res)3个浓度给药组。应用流式细胞术和瑞氏-吉姆萨染色法检测外周血及脾细胞悬液中白血病细胞百分比,HE染色法观察脾脏和骨髓组织病理形态,RT-q PCR法检测脾脏组织中Notch1、Hes-1、c-Myc、mi R-19b和PTEN m RNA表达水平,Western blot法检测Notch1、Hes-1、c-Myc、p-PTEN和PTEN蛋白表达水平。结果:与对照组相比,T-ALL组小鼠外周血中白血病细胞明显增多,脾脏及骨髓组织中白血病细胞弥漫性浸润,脾脏中Notch1、Hes-1、c-Myc、mi R-19b m RNA表达水平和Notch1、Hes-1、c-Myc蛋白表达水平均明显增高(P<0.01),PTEN m RNA及其蛋白水平显著降低(P<0.01),经白藜芦醇处理后,H-Res组以上各项指标较T-ALL组均获得逆转。结论:白藜芦醇具有抗小鼠T-ALL的作用,其机制可能通过抑制Notch1信号通路发挥作用。
