Objective To examine the effect of neuropeptide Y (NPY) on TGF-β1 production in RAW264.7 macrophages. Methods Enzyme linked immunosorbent assay (ELISA) was used to detect TGF-β1 production. Cell counting kit 8 ...Objective To examine the effect of neuropeptide Y (NPY) on TGF-β1 production in RAW264.7 macrophages. Methods Enzyme linked immunosorbent assay (ELISA) was used to detect TGF-β1 production. Cell counting kit 8 (CCK-8) was used to assay the viability of RAW264.7 cells. Western blot was used to detect the phosphorylation of PI3K p85. Results NPY treatment could promote TGF-β1 production and rapid phosphorylation of PI3K p85 in RAW264.7 cells via Y1 receptor. The elevated TGF-β 1 production induced by NPY could be abolished by wortrnannin pretreatment. Conclusion NPY may elicit TGF-β production in RAW264.7 cells via Y1 receptor, and the activated PI3K pathway may account for this effect.展开更多
AIM: To investigate the functional significance of insulin-like growth factor binding protein-5 (IGFBP-5) overexpression in pancreatic cancer (PaC).METHODS: The effects of IGFBP-5 on cell growth were assessed by...AIM: To investigate the functional significance of insulin-like growth factor binding protein-5 (IGFBP-5) overexpression in pancreatic cancer (PaC).METHODS: The effects of IGFBP-5 on cell growth were assessed by stable transfection of BxPC-3 and PANC-1 cell lines and measuring cell number and DNA synthesis. Alterations in the cell cycle were assessed by flow cytometry and immunoblot analyses. Changes in cell survival and signal transduction were evaluated after mitogen and phosphatidylinositol activated protein kinase 3-kinase (PI3K) inhibitor treatment.RESULTS: After serum deprivation, IGFBP-5 expression increased both cell number and DNA synthesis in BxPC-3 cells, but reduced cell number in PANC-1 cells. Consistent with this observation, cell cycle analysis of IGFBP-5-expressing cells revealed accelerated cell cycle progression in BxPC-3 and G2/M arrest of PANC-1 cells. Signal transduction analysis revealed that Akt activation was increased in BxPC-3, but reduced in PANC-1 cells that express IGFBP-5. Inhibition of PI3K with LY294002 suppressed extracellular signal-regulated kinase-1 and -2 (ERK1/2) activation in BxPC-3, but enhanced ERK1/2 activation in PANC-1 cells that express IGFBP-5. When MEK1/2 was blocked, Akt activation remained elevated in IGFBP-5 expressing PaC cells; however, inhibition of PI3K or MEK1/2 abrogated IGFBP-5-mediated cell survival.CONCLUSION: These results indicate that IGFBP-5 expression affects the cell cycle and survival signal pathways and thus it may be an important mediator of PaC cell growth.展开更多
Objective To explore the therapeutic effect and mechanism of Bushen Tiansui Decoction(补肾填髓方,BSTSD)and its active component icariin on Alzheimer’s disease(AD).Methods(i)Animal experiments.This study conducted exp...Objective To explore the therapeutic effect and mechanism of Bushen Tiansui Decoction(补肾填髓方,BSTSD)and its active component icariin on Alzheimer’s disease(AD).Methods(i)Animal experiments.This study conducted experiments using specific pathogen-free(SPF)grade male C57BL/6J wild-type(WT)mice and APP/PS1 double transgenic mice.The animals were divided into three groups:WT group(WT mice,n=5,receiving distilled wa-ter daily),APP/PS1 group(APP/PS1 double transgenic mice,n=5,receiving distilled water daily),and BSTSD group[APP/PS1 double transgenic mice,n=5,treated with BSTSD suspen-sion at a dosage of 27 g/(kg·d)for 90 d].Cognitive function was assessed using the Morris wa-ter maze(MWM).Post-experiment,hippocampal tissues were collected for analysis of pyra-midal cell and synaptic morphology through hematoxylin-eosin(HE)staining and transmis-sion electron microscopy(TEM).(ii)Cell experiments.The HT-22 cells were divided into con-trol group(untreated),Aβ_(25-35) group(treated with 20μmol/L Aβ_(25-35) for 24 h),icariin group(pre-treated with 20μmol/L icariin for 60 min,followed by 20μmol/L Aβ_(25-35) for an additional 24 h),and icariin+LY294002 group[treated with 20μmol/L icariin and 20μmol/L LY294002(an inhibitor of the phosphoinostitide 3-kinases(PI3K)signaling pathway)for 60 min,then exposed to 20μmol/L Aβ_(25-35) for 24 h],and cell viability was measured.Western blot was used to detect the expression levels of synapse-associated proteins[synaptophysin(SYP)and post-synaptic density-95(PSD-95)]and PI3K signaling pathway associated proteins[phosphorylat-ed(p)-PI3K/PI3K,p-protein kinase B(Akt)/Akt,and p-mechanistic target of rapamycin(mTOR)/mTOR].Results(i)Animal experiments.Compared with APP/PS1 group,BSTSD group showed that escape latency was significantly shortened(P<0.01)and the frequency of crossing the origi-nal platform was significantly increased(P<0.01).Morphological observation showed that pyramidal cells in the hippocampal CA1 region were arranged more regularly,nuclear stain-ing was uniform,and vacuole-like changes were reduced after BSTSD treatment.TEM showed that the length of synaptic active zone in BSTSD treatment group was increased com-pared with APP/PS1 group(P<0.01),and the width of synaptic gap was decreased(P<0.01).(ii)Cell experiments.Icariin had no obvious toxicity to HT-22 cells when the concentration was not more than 20μmol/L(P>0.05),and alleviated the cell viability decline induced by Aβ_(25-35)(P<0.01).Western blot results showed that compared with Aβ_(25-35) group,the ratios of p-PI3K/PI3K,p-Akt/Akt and p-mTOR/mTOR in icariin group were significantly increased(P<0.01),while the protein expression levels of SYP and PSD-95 were increased(P<0.01).These effects were blocked by LY294002(P<0.01).Conclusion BSTSD and icariin enhance cognitive function and synaptic integrity in AD mod-els and provide potential therapeutic strategies through activation of the PI3K/Akt/mTOR pathway.展开更多
The phosphatidylinositol 3-kinase(PI3K)-AKT pathway is involved in various cellular functions, including anti-apoptosis, protein synthesis, glucose metabolism and cell cycling. However, the role of the PI3K-AKT pathwa...The phosphatidylinositol 3-kinase(PI3K)-AKT pathway is involved in various cellular functions, including anti-apoptosis, protein synthesis, glucose metabolism and cell cycling. However, the role of the PI3K-AKT pathway in crustaceans remains unclear. In the present study, we cloned and characterized the AKT gene lvakt from Litopenaeus vannamei. The 511-residue LVAKT was highly conserved; contained a PH domain, a catalytic domain and a hydrophobic domain; and was highly expressed in the heart and gills of L. vannamei. We found, using Real-Time Quantitative PCR(Q-PCR) analysis, that lvakt was upregulated during early white spot syndrome virus(WSSV) infection. Moreover, the PI3K-specific inhibitor, LY294002, reduced viral gene transcription, implying that the PI3K-AKT pathway might be hijacked by WSSV. Our results therefore suggest that LVAKT may play an important role in the shrimp immune response against WSSV.展开更多
HRONIC myeloid leukemia (CML) is characterized by the presence of the BCR/ABL fusion gene, which is the result of a reciprocal translo cation between chromosomes 9 and 22, calledPhiladelphia (Ph) chromosome. Imati...HRONIC myeloid leukemia (CML) is characterized by the presence of the BCR/ABL fusion gene, which is the result of a reciprocal translo cation between chromosomes 9 and 22, calledPhiladelphia (Ph) chromosome. Imatinib mesylate (imatinib), a specific small molecular inhibitor of BCR/ABL, could improve the prognosis of CML and is now the standard drug applied in all phases of this disease} Despite the efficacy of imatinib, the development of resistance and the persistence of minimal residual disease have seriously impaired the efficiency of this medicine. Resistance may develop through several different mechanisms, such as mutations in the Abl kinase domain, BCR/ABL overexpression, or compensatory phosphatidylinositol 3 kinase (PI3K)/Akt/ mammalian target of rapamycin (mTOR) activation.2,3 Rapamycin, with mTOR as a potential therapeutic target, has been studied in patients with hematologic malignancies. Here we report a case of refractory CML myeloid blast crisissuccessfully treated by the combination of rapamycin and imatinib.展开更多
The epidermal growth factor receptor (EGFR) is a member of the ErbB/EGFR family, including EGFR/Herl, ErbB2/Her2, ErbB-3/Her3, and ErbB-4/Her4. EGFR exerts its effects through the receptor tyrosine kinase phosphoryl...The epidermal growth factor receptor (EGFR) is a member of the ErbB/EGFR family, including EGFR/Herl, ErbB2/Her2, ErbB-3/Her3, and ErbB-4/Her4. EGFR exerts its effects through the receptor tyrosine kinase phosphorylation and activation of important downstream signaling pathways in normal and neoplastic cells, mainly the Ras GTPase/MAP kinase (MAPK), STAT3, and phosphatidylinositide 3 kinase-AKT pathways. EGFR deregulation is common in malignant glioma, especially primary glioblastoma, and exists in three forms: gene overexpression (amplification), autocrine effects of EGFR activation, and activating receptor mutation (EGFRvlII). However, some EGFR abnormalities have also been found in low-grade gliomas, including the nuclear localization of EGFR, expression in the microfoci of anaplastic transformation, and association with neovascularization in the mesenchyma of the glioma, which suggests that some unknown EGFR-related mechanisms are possibly responsible for its central role in the initiation and progression of malignant glioma. Uncovering these mechanisms will have potential value in the development of radio- therapy, chemotherapy, and EGFR-targeted therapy for glioma.展开更多
文摘Objective To examine the effect of neuropeptide Y (NPY) on TGF-β1 production in RAW264.7 macrophages. Methods Enzyme linked immunosorbent assay (ELISA) was used to detect TGF-β1 production. Cell counting kit 8 (CCK-8) was used to assay the viability of RAW264.7 cells. Western blot was used to detect the phosphorylation of PI3K p85. Results NPY treatment could promote TGF-β1 production and rapid phosphorylation of PI3K p85 in RAW264.7 cells via Y1 receptor. The elevated TGF-β 1 production induced by NPY could be abolished by wortrnannin pretreatment. Conclusion NPY may elicit TGF-β production in RAW264.7 cells via Y1 receptor, and the activated PI3K pathway may account for this effect.
基金Supported by A grant from the Arkansas Master Tobacco Settlement and Arkansas Biosciences Institute
文摘AIM: To investigate the functional significance of insulin-like growth factor binding protein-5 (IGFBP-5) overexpression in pancreatic cancer (PaC).METHODS: The effects of IGFBP-5 on cell growth were assessed by stable transfection of BxPC-3 and PANC-1 cell lines and measuring cell number and DNA synthesis. Alterations in the cell cycle were assessed by flow cytometry and immunoblot analyses. Changes in cell survival and signal transduction were evaluated after mitogen and phosphatidylinositol activated protein kinase 3-kinase (PI3K) inhibitor treatment.RESULTS: After serum deprivation, IGFBP-5 expression increased both cell number and DNA synthesis in BxPC-3 cells, but reduced cell number in PANC-1 cells. Consistent with this observation, cell cycle analysis of IGFBP-5-expressing cells revealed accelerated cell cycle progression in BxPC-3 and G2/M arrest of PANC-1 cells. Signal transduction analysis revealed that Akt activation was increased in BxPC-3, but reduced in PANC-1 cells that express IGFBP-5. Inhibition of PI3K with LY294002 suppressed extracellular signal-regulated kinase-1 and -2 (ERK1/2) activation in BxPC-3, but enhanced ERK1/2 activation in PANC-1 cells that express IGFBP-5. When MEK1/2 was blocked, Akt activation remained elevated in IGFBP-5 expressing PaC cells; however, inhibition of PI3K or MEK1/2 abrogated IGFBP-5-mediated cell survival.CONCLUSION: These results indicate that IGFBP-5 expression affects the cell cycle and survival signal pathways and thus it may be an important mediator of PaC cell growth.
基金Hunan Provincial Natural Science Foundation of China(2022JJ40220)Health Commission of Hunan Province(B202303106781)Hunan Administration of Traditional Chinese Medicine(2021192).
文摘Objective To explore the therapeutic effect and mechanism of Bushen Tiansui Decoction(补肾填髓方,BSTSD)and its active component icariin on Alzheimer’s disease(AD).Methods(i)Animal experiments.This study conducted experiments using specific pathogen-free(SPF)grade male C57BL/6J wild-type(WT)mice and APP/PS1 double transgenic mice.The animals were divided into three groups:WT group(WT mice,n=5,receiving distilled wa-ter daily),APP/PS1 group(APP/PS1 double transgenic mice,n=5,receiving distilled water daily),and BSTSD group[APP/PS1 double transgenic mice,n=5,treated with BSTSD suspen-sion at a dosage of 27 g/(kg·d)for 90 d].Cognitive function was assessed using the Morris wa-ter maze(MWM).Post-experiment,hippocampal tissues were collected for analysis of pyra-midal cell and synaptic morphology through hematoxylin-eosin(HE)staining and transmis-sion electron microscopy(TEM).(ii)Cell experiments.The HT-22 cells were divided into con-trol group(untreated),Aβ_(25-35) group(treated with 20μmol/L Aβ_(25-35) for 24 h),icariin group(pre-treated with 20μmol/L icariin for 60 min,followed by 20μmol/L Aβ_(25-35) for an additional 24 h),and icariin+LY294002 group[treated with 20μmol/L icariin and 20μmol/L LY294002(an inhibitor of the phosphoinostitide 3-kinases(PI3K)signaling pathway)for 60 min,then exposed to 20μmol/L Aβ_(25-35) for 24 h],and cell viability was measured.Western blot was used to detect the expression levels of synapse-associated proteins[synaptophysin(SYP)and post-synaptic density-95(PSD-95)]and PI3K signaling pathway associated proteins[phosphorylat-ed(p)-PI3K/PI3K,p-protein kinase B(Akt)/Akt,and p-mechanistic target of rapamycin(mTOR)/mTOR].Results(i)Animal experiments.Compared with APP/PS1 group,BSTSD group showed that escape latency was significantly shortened(P<0.01)and the frequency of crossing the origi-nal platform was significantly increased(P<0.01).Morphological observation showed that pyramidal cells in the hippocampal CA1 region were arranged more regularly,nuclear stain-ing was uniform,and vacuole-like changes were reduced after BSTSD treatment.TEM showed that the length of synaptic active zone in BSTSD treatment group was increased com-pared with APP/PS1 group(P<0.01),and the width of synaptic gap was decreased(P<0.01).(ii)Cell experiments.Icariin had no obvious toxicity to HT-22 cells when the concentration was not more than 20μmol/L(P>0.05),and alleviated the cell viability decline induced by Aβ_(25-35)(P<0.01).Western blot results showed that compared with Aβ_(25-35) group,the ratios of p-PI3K/PI3K,p-Akt/Akt and p-mTOR/mTOR in icariin group were significantly increased(P<0.01),while the protein expression levels of SYP and PSD-95 were increased(P<0.01).These effects were blocked by LY294002(P<0.01).Conclusion BSTSD and icariin enhance cognitive function and synaptic integrity in AD mod-els and provide potential therapeutic strategies through activation of the PI3K/Akt/mTOR pathway.
基金Supported by the Scientific Research Foundation of Third Institute of Oceanography,SOA(No.2011018)the Natural Science Foundation of Fujian Province of China(No.2011J05079)+3 种基金the National Natural Science Foundation of China(No.31001125)the Major State Basic Research Development Program of China(973 Program)(No.2012CB114403)the National High Technology Research and Development Program of China(863 Program)(No.2012AA092205)the China Agriculture Research System-47
文摘The phosphatidylinositol 3-kinase(PI3K)-AKT pathway is involved in various cellular functions, including anti-apoptosis, protein synthesis, glucose metabolism and cell cycling. However, the role of the PI3K-AKT pathway in crustaceans remains unclear. In the present study, we cloned and characterized the AKT gene lvakt from Litopenaeus vannamei. The 511-residue LVAKT was highly conserved; contained a PH domain, a catalytic domain and a hydrophobic domain; and was highly expressed in the heart and gills of L. vannamei. We found, using Real-Time Quantitative PCR(Q-PCR) analysis, that lvakt was upregulated during early white spot syndrome virus(WSSV) infection. Moreover, the PI3K-specific inhibitor, LY294002, reduced viral gene transcription, implying that the PI3K-AKT pathway might be hijacked by WSSV. Our results therefore suggest that LVAKT may play an important role in the shrimp immune response against WSSV.
基金Supported by Key Provincial Talents Program of Jiangsu(H201126)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘HRONIC myeloid leukemia (CML) is characterized by the presence of the BCR/ABL fusion gene, which is the result of a reciprocal translo cation between chromosomes 9 and 22, calledPhiladelphia (Ph) chromosome. Imatinib mesylate (imatinib), a specific small molecular inhibitor of BCR/ABL, could improve the prognosis of CML and is now the standard drug applied in all phases of this disease} Despite the efficacy of imatinib, the development of resistance and the persistence of minimal residual disease have seriously impaired the efficiency of this medicine. Resistance may develop through several different mechanisms, such as mutations in the Abl kinase domain, BCR/ABL overexpression, or compensatory phosphatidylinositol 3 kinase (PI3K)/Akt/ mammalian target of rapamycin (mTOR) activation.2,3 Rapamycin, with mTOR as a potential therapeutic target, has been studied in patients with hematologic malignancies. Here we report a case of refractory CML myeloid blast crisissuccessfully treated by the combination of rapamycin and imatinib.
文摘The epidermal growth factor receptor (EGFR) is a member of the ErbB/EGFR family, including EGFR/Herl, ErbB2/Her2, ErbB-3/Her3, and ErbB-4/Her4. EGFR exerts its effects through the receptor tyrosine kinase phosphorylation and activation of important downstream signaling pathways in normal and neoplastic cells, mainly the Ras GTPase/MAP kinase (MAPK), STAT3, and phosphatidylinositide 3 kinase-AKT pathways. EGFR deregulation is common in malignant glioma, especially primary glioblastoma, and exists in three forms: gene overexpression (amplification), autocrine effects of EGFR activation, and activating receptor mutation (EGFRvlII). However, some EGFR abnormalities have also been found in low-grade gliomas, including the nuclear localization of EGFR, expression in the microfoci of anaplastic transformation, and association with neovascularization in the mesenchyma of the glioma, which suggests that some unknown EGFR-related mechanisms are possibly responsible for its central role in the initiation and progression of malignant glioma. Uncovering these mechanisms will have potential value in the development of radio- therapy, chemotherapy, and EGFR-targeted therapy for glioma.