scholarly journals Lactoferrin Induces Osteoblast Growth through IGF-1R

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Jian-Ming Hou ◽  
En-Yu Chen ◽  
Fan Lin ◽  
Qing-Ming Lin ◽  
Ying Xue ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Western Blot ◽  
Dependent Manner ◽  
Osteoblast Proliferation ◽  
Rt Pcr ◽  
Concentration Dependent Manner ◽  
Empty Vector ◽  
Significant Difference ◽  
Group 3

Objectives.To investigate the role of the IGF-1R by which lactoferrin induces osteoblast growth.Methods.Osteoblast received 5 d lactoferrin intervention at a concentration of 0.1, 1, 10, 100, and 1000 μg/mL, and the IGF-1 and IGF-1R were detected using RT-PCR and western blot. The osteoblast into the control, 100 μg/mL lactoferrin, Neo-scramble (NS, empty vector), NS + 100 μg/mL lactoferrin, shIGF-1R and shIGF-1R + 100 μg/mL lactoferrin group. We test the apoptosis and proliferation and the level of PI3K and RAS in osteoblasts after 5 d intervention.Results.(1) 1, 10, 100, and 1000 μg/mL lactoferrin induced the expression of IGF-1 mRNA and protein. 10 μg/mL and 100 μg/mL lactoferrin induced the expression of IGF-1R mRNA and protein. (2) Lactoferrin (100 μg/mL) induced osteoblast proliferation while inhibiting apoptosis. Osteoblasts with silenced IGF-1R exhibited decreased proliferation but increased apoptosis. MMT staining and flow cytometry both indicated that there was no significant difference between the shIGF-1R group and the shIGF-1R + 100 μg/mL lactoferrin group. (3) Lactoferrin (100 μg/mL) induced PI3K and RAS phosphorylation and silence of IGF-1R resulted in decreased p-PI3K and p-RAS expression. Lactoferrin-treated shIGF-1R cells showed significantly higher level of p-PI3K and p-RAS when compared with shIGF-1R.Conclusion.Lactoferrin induced IGF-1/IGF-1R in a concentration-dependent manner. Lactoferrin promoted osteoblast proliferation while inhibiting apoptosis through IGF-1R. Lactoferrin activated PI3K and RAS phosphorylation via an IGF-1R independent pathway.

Effects of Buthus martensii Karsch Venom on Cell Proliferation and Cytotoxicity in Hela Cells

2011 ◽  
Vol 345 ◽  
pp. 393-398 ◽  
Author(s):  
Zhi Wang ◽  
Wen Hui Fu ◽  
Xiang Yang Lu ◽  
Guang Xian Cai
Keyword(s):  
Hela Cell ◽  
Hela Cells ◽  
Inhibitory Concentration ◽  
Scorpion Venom ◽  
Dependent Manner ◽  
Hela Cell Line ◽  
Rt Pcr ◽  
Concentration Dependent Manner ◽  
Significant Difference ◽  
Apoptosis And Necrosis

This paper focuses on the effect of the venom of the scorpion Buthus martensii on the proliferation of human cervical carcinoma Hela cell line and the related molecular mechanism. MTT test showed that the scorpion venom inhibited proliferation of Hela cells in time-dependent and concentration-dependent manner with 50% inhibitory concentration (IC50) of 34.5 μg/mL(48 h). By using flow cytometry, it was found that the scorpion venom could induce apoptosis and necrosis in Hela cells. RT-PCR and Western blot indicated there were obviously up-regulated in the expressions of p21 protein but the expression of p21 mRNA showed no significant difference in the Hela cell by the scorpion venom. These results suggest that the possible mechanism of the scorpion venom is to activate the expressions of p21 protein and to cause Hela cell apoptosis.

scholarly journals Artesunate prevents knee intraarticular adhesion via PRKR-like ER kinase (PERK) signal pathway

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Hui Chen ◽  
Jin Tao ◽  
Jingcheng Wang ◽  
Lianqi Yan
Keyword(s):  
Flow Cytometry ◽  
Western Blot ◽  
Joint Stiffness ◽  
Immunohistochemical Analysis ◽  
Time Dependent ◽  
Cell Counting ◽  
Initiation Factor ◽  
Dependent Manner ◽  
Related Protein ◽  
Concentration Dependent Manner

Abstract Background Intraarticular scar adhesion refers to a serious complication caused by knee surgery or trauma, leading to various sequelae (e.g., articular cartilage degeneration and knee joint stiffness). Artesunate (ART) has exhibited an effect to suppress fibroblast proliferation, whereas the exact mechanism remains unclear. This study aims to delve into the possible mechanism of ART in suppressing joint adhesion. Methods The effect of ART on reduced intraarticular adhesions was ascertained by histological staining and immunohistochemical analysis through vivo experiments. Cell Counting Kit-8 (CCK-8) assay, Western blot analysis, flow cytometry, and tunnel staining were used to detect the effect of ART in promoting fibroblast apoptosis and delve into its possible signaling pathway. Results The results of hematoxylin-eosin (HE) staining suggested that the number of fibroblasts decreased with the increase in ART concentration. The results of Masson staining were similar, with the increase in concentration, the collagen content decreased. Immunohistochemical results showed that the expression of endoplasmic reticulum stress (ERS) characteristic proteins 78 kDa glucose-regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP) increased in a concentration-dependent manner. CCK-8 results suggested that ART could inhibit fibroblast viability in a concentration- and time-dependent manner. Results of flow cytometry, tunnel staining, and Western blot suggested the apoptosis of fibroblasts occurred after ART treatment. Cells with caspase inhibitors were treated, and apoptotic proteins cleaved-poly ADP-ribose polymerase (cleaved PARP) and cleaved-caspase 3 were detected; the results showed that the apoptotic effect of ART was reduced. The expressions of ERS-related protein CHOP and apoptosis-related protein Bax were upregulated, while the expression of Bcl-2 was downregulated, and the ratio of Bax/Bcl-2 increased in a concentration-dependent manner. Continuous detection of PRKR-like ER kinase (PERK) pathway-related proteins showed that the expression of p-PERK and phosphorylating eukaryotic initiation factor 2α (p-eIF2α) increased in a time-dependent and concentration-dependent manner. PERK pathway inhibitors could partially inhibit ART-mediated apoptosis through PERK pathway. Conclusions ART can promote fibroblast apoptosis through PERK pathway, a classical ERS pathway, and thus prevent fibrosis in the surgical area after joint surgery.

The tyrosine kinase src plays a crucial role in leukemic cell proliferation in AML

2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 10531-10531
Author(s):  
G. Schuch ◽  
E. Schäfer ◽  
K. Eggert ◽  
S. Loges ◽  
M. Görn ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Western Blot ◽  
Cell Lines ◽  
Crucial Role ◽  
Leukemic Cell ◽  
Leukemic Cells ◽  
Clinical Samples ◽  
Dependent Manner ◽  
Rt Pcr

10531 Background: Src-family tyrosine kinases are known to be involved in signal transduction pathways of growth factors and cytokines in hematopoetic cells. While the role of other src family members has been studied widely, only few data exist about c-src in leukemia. The actual study was performed to analyze src mutations in leukemic cells and to determine the role of pp60src in leukemic cell proliferation. Methods: AML cell lines and primary samples were analyzed for expression and activation of src by RT-PCR and Western blot analyses. Mutational analyses were performed by sequencing of C-terminal cDNA from 60 AML samples. The effects of src inhibition were studied by src-specific inhibitors PP1 and PP2 or by siRNA transfection. Effetcs of src inhibition were monitored in proliferation assays and analyzes of signalling through Erk1/2 and apoptosis by annexin V staining and DNA laddering. Results: In all 60 patients analyzed expression of c-src mRNA was detected by RT-PCR. Western blot analyses confirmed strong expression of src on the protein level and revealed a robust activation of the protein as determined by tyrosine phosphorylation. Incubation of leukemic cells with PP1 and PP2 caused significant inhibition of proliferation in a dose dependent manner. Similar results were observed after transfection with specific siRNAs. Src inhibition blocked phosphorylation of pp60src, Erk1/2 and induced apoptosis in leukemic cells. Mutational analyses as performed by SSCP/heteroduplex and bi-directionally sequencing revealed wildtype sequence in cell lines and 60 clinical samples. Conclusions: In summary, pp60src is highly expressed and activated in cell lines and clinical samples of human AML. Moreover, phosphorylation of src is essential for leukemic cell proliferation. Underlying mutations in the coding sequence of c-src causing constitutive activation could be excluded. These data suggest that pp60src plays a crucial role in AML and src inhibition by targeted therapy might offer a useful new approach in the treatment of AML. No significant financial relationships to disclose.

Proteasome Inhibition with Bortezomib Induces Apoptosis of Long-Lived Plasma Cells in Steroid-Resistant or Relapsed Immune Thrombocytopaenia

2018 ◽  
Vol 118 (10) ◽  
pp. 1752-1764 ◽  
Author(s):  
Guosheng Li ◽  
Shuang Wang ◽  
Na Li ◽  
Yang Liu ◽  
Qi Feng ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Elispot Assay ◽  
Plasma Cells ◽  
Proteasome Inhibition ◽  
Proteasome Activity ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Significant Difference ◽  
Apoptosis Assay

AbstractPrimary immune thrombocytopaenia (ITP) is the most common haemorrhagic disease. Although most patients respond initially to mainstream therapies, such as corticosteroids, immunosuppressants or rituximab, a large proportion of patients fail to respond or relapse. These treatments only affect B lymphocytes or short-lived plasma cells, but not already existing long-lived plasma cells (LLPCs) which persistently secrete antibodies. We hypothesized that LLPCs may play a role in the corticosteroid-resistant or relapsed ITP patients, and bortezomib, a proteasome inhibitor, may act on plasma cells and offer a therapeutic effect. Although a significant difference in the proportion of CD19−CD38hiCD138+ total LLPCs was not observed by flow cytometry, a glycoprotein (GP) IIb/IIIa-specific enzyme-linked immunosorbent spot (ELISpot) assay of sorted CD19−CD138+ LLPCs confirmed the existence of anti-platelet antibody-secreting LLPCs in ITP patients in contrast to healthy controls. Moreover, the LLPCs could be eliminated in the presence of bortezomib by ELISpot assay, which was also confirmed by flow cytometry. Accordingly, a modified monoclonal antibody immobilization of platelet antigen assay of sorted CD19−CD138+ LLPCs revealed that the concentration of anti-platelet antibodies decreased remarkably when cultured with 0.25 ng/mL bortezomib for 5 days. The apoptosis assay demonstrated that bortezomib could induce apoptosis of LLPCs in a concentration-dependent manner. The proteasome activity assay showed that bortezomib significantly reduced the proteasome activity in sorted CD19−CD138+ LLPCs. Furthermore, in active ITP murine models, bortezomib eliminated LLPCs in vivo and alleviated thrombocytopaenia. We conclude that LLPCs participate in the pathogenesis of ITP and bortezomib may have potential as a novel therapeutic regimen.

scholarly journals The Expression of HMGB1 in Bone Marrow MSCs Is Upregulated by Hypoxia with Regulatory Effects on the Apoptosis and Adhesion

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Mei-Yun Tan ◽  
Cai-Dong Zhang ◽  
Bo Xia ◽  
Jiang Guo ◽  
Zhong-Wei Fan ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Cell Biology ◽  
High Mobility ◽  
Dependent Manner ◽  
Bone Marrow Mscs ◽  
Rt Pcr ◽  
High Concentration ◽  
Concentration Dependent Manner ◽  
Regulatory Effects

Background and Aims. Hypoxia regulates the survival of mesenchymal stem cells (MSCs) but the mechanism is unclear. In hypoxia, the level of high mobility group box 1 (HMGB1) was increased in many cells which may be involved in the regulation of cell biology. The aim is to determine whether hypoxia affects the expression of HMGB1 in bone marrow MSCs (BM-MSCs) and to investigate the role of HMGB1 in the apoptosis and adhesion.Methods. BM-MSCs were exposed to hypoxia (1% O2) and normoxia (20% O2) and the expression of HMGB1 was measured by RT-PCR and western blotting. The apoptosis and adhesion of BM-MSCs were evaluated after interfered by different concentrations of HMGB1.Results. Expression of HMGB1 in BM-MSCs showed a significant upregulation in hypoxia when compared to those in normoxia. The adhesion of BM-MSCs was increased by HMGB1 in a concentration-dependent manner; the apoptosis effect of HMGB1 depended on its concentrations: HMGB1 at low concentration (50 ng/mL) promoted the apoptosis of BM-MSCs while HMGB1 at high concentration (≥100 ng/mL) reduced this apoptosis.Conclusions. Hypoxia enhanced the expression of HMGB1 in BM-MSCs with influences on apoptosis and adhesion and this could have a significant effect on the regenerative potential of MSC-based strategies.

scholarly journals Emodin promotes fibroblast apoptosis and prevents epidural fibrosis through PERK pathway in rats

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Guirun Xiong ◽  
Hui Chen ◽  
Qi Wan ◽  
Jihang Dai ◽  
Yu Sun ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Western Blot ◽  
Fibrous Tissue ◽  
Inhibitory Effect ◽  
Tunel Assay ◽  
Cell Counting ◽  
Dependent Manner ◽  
Epidural Fibrosis ◽  
Concentration Dependent Manner ◽  
Apoptotic Protein

Abstract Background Laminectomy is usually classed as a common orthopedic surgery, but postoperative epidural fibrosis often leads to less-than-desirable clinical outcomes. As demonstrated by prior studies, emodin (EMO) exerts an anti-fibrotic effect. Here, we carried out investigation into the inhibitory effect created by EMO application on epidural fibrosis after laminectomy in rats. Methods The paper conducts a series of experiment. In vitro, we observed the effect of EMO on fibroblasts by Cell Counting Kit-8 (CCK-8) assay. Apoptosis of fibroblasts induced by EMO was detected by western blot, TUNEL assay, and flow cytometry. The results revealed that EMO was capable of inducing fibroblast apoptosis, and the proteins of PERK pathway also changed accordingly. In vivo, the effect of EMO on epidural fibrosis in 12 male Sprague-Dawley rats was observed by histological staining. Results CCK-8 assay indicated that EMO was effective in reducing fibroblast viability in a time- and a dose-dependent manner. TUNEL assay and flow cytometry analysis have demonstrated that the apoptotic rate of fibroblasts increased as the EMO concentration rose. Western blot analysis proved that EMO promoted the relative expression of p-perk and p-eIF2α and that the expression of its downstream proteins CHOP and GRP78 was also enhanced. The expression of apoptotic protein Bax and cleaved PARP was upregulated, whereas the expression of anti-apoptotic protein Bcl-2 was downregulated. In addition, histological and immunohistochemical analysis demonstrated that EMO functioned to inhibit epidural fibrosis and increase GRP78 expression in fibrous tissue by promoting apoptosis of fibroblasts. Conclusions EMO could have inhibitory effect on epidural fibrosis in a concentration-dependent manner. The potential mechanism might be through PERK signaling pathway to promote fibroblast apoptosis. It has a possibility to be taken as a novel method for the treatment of epidural fibrosis.

scholarly journals Endothelial cell-related autophagic pathways in Sugen/hypoxia-exposed pulmonary arterial hypertensive rats

2017 ◽  
Vol 313 (5) ◽  
pp. L899-L915 ◽  
Author(s):  
Fumiaki Kato ◽  
Seiichiro Sakao ◽  
Takao Takeuchi ◽  
Toshio Suzuki ◽  
Rintaro Nishimura ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Endothelial Cell ◽  
Vascular Remodeling ◽  
Time Dependent ◽  
Causative Role ◽  
Dependent Manner ◽  
Vascular Endothelial ◽  
Pulmonary Vascular Remodeling ◽  
Pulmonary Arterial

Pulmonary arterial hypertension (PAH) is characterized by progressive obstructive remodeling of pulmonary arteries. However, no reports have described the causative role of the autophagic pathway in pulmonary vascular endothelial cell (EC) alterations associated with PAH. This study investigated the time-dependent role of the autophagic pathway in pulmonary vascular ECs and pulmonary vascular EC kinesis in a severe PAH rat model (Sugen/hypoxia rat) and evaluated whether timely induction of the autophagic pathway by rapamycin improves PAH. Hemodynamic and histological examinations as well as flow cytometry of pulmonary vascular EC-related autophagic pathways and pulmonary vascular EC kinetics in lung cell suspensions were performed. The time-dependent and therapeutic effects of rapamycin on the autophagic pathway were also assessed. Sugen/hypoxia rats treated with the vascular endothelial growth factor receptor blocker SU5416 showed increased right ventricular systolic pressure (RVSP) and numbers of obstructive vessels due to increased pulmonary vascular remodeling. The expression of the autophagic marker LC3 in ECs also changed in a time-dependent manner, in parallel with proliferation and apoptotic markers as assessed by flow cytometry. These results suggest the presence of cross talk between pulmonary vascular remodeling and the autophagic pathway, especially in small vascular lesions. Moreover, treatment of Sugen/hypoxia rats with rapamycin after SU5416 injection activated the autophagic pathway and improved the balance between cell proliferation and apoptosis in pulmonary vascular ECs to reduce RVSP and pulmonary vascular remodeling. These results suggested that the autophagic pathway can suppress PAH progression and that rapamycin-dependent activation of the autophagic pathway could ameliorate PAH.

The P-element-induced silencing effect of KP transposons is dose dependent in Drosophila melanogaster

Genome ◽  
2011 ◽  
Vol 54 (9) ◽  
pp. 752-762 ◽  
Author(s):  
Alireza Sameny ◽  
John Locke
Keyword(s):  
Drosophila Melanogaster ◽  
Critical Role ◽  
Mutagenic Effect ◽  
P Element ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
P Elements ◽  
Single Well ◽  
Dose Dependent

Transposable elements are found in the genomes of all eukaryotes and play a critical role in altering gene expression and genome organization. In Drosophila melanogaster, transposable P elements are responsible for the phenomenon of hybrid dysgenesis. KP elements, a deletion-derivative of the complete P element, can suppress this mutagenic effect. KP elements can also silence the expression of certain other P-element-mediated transgenes in a process called P-element-dependent silencing (PDS), which is thought to involve the recruitment of heterochromatin proteins. To explore the mechanism of this silencing, we have mobilized KP elements to create a series of strains that contain single, well-defined KP insertions that show PDS. To understand the quantitative role of KP elements in PDS, these single inserts were combined in a series of crosses to obtain genotypes with zero, one, or two KP elements, from which we could examine the effect of KP gene dose. The extent of PDS in these genotypes was shown to be dose dependent in a logarithmic rather than linear fashion. A logarithmic dose dependency is consistent with the KP products interacting with heterochromatic proteins in a concentration-dependent manner such that two molecules are needed to induce gene silencing.

Protein kinase C potentiates cAMP-stimulated mouse duodenal mucosal bicarbonate secretion in vitro

2004 ◽  
Vol 286 (5) ◽  
pp. G814-G821 ◽  
Author(s):  
Bi-Guang Tuo ◽  
Jimmy Y. C. Chow ◽  
Kim E. Barrett ◽  
Jon I. Isenberg
Keyword(s):  
Short Circuit ◽  
Short Circuit Current ◽  
Duodenal Mucosa ◽  
Bicarbonate Secretion ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Ussing Chambers ◽  
Duodenal Bicarbonate Secretion

PKC has been shown to regulate epithelial Cl- secretion in a variety of models. However, the role of PKC in duodenal mucosal bicarbonate secretion is less clear. We aimed to investigate the role of PKC in regulation of duodenal mucosal bicarbonate secretion. Bicarbonate secretion by murine duodenal mucosa was examined in vitro in Ussing chambers using a pH-stat technique. PKC isoform expression and activity were assessed by Western blotting and in vitro kinase assays, respectively. PMA (an activator of PKC) alone had no effect on duodenal bicarbonate secretion or short-circuit current ( Isc). When PMA and dibutyryl-cAMP (db-cAMP) were added simultaneously, PMA failed to alter db-cAMP-stimulated duodenal bicarbonate secretion or Isc ( P > 0.05). However, a 1-h preincubation with PMA potentiated db-cAMP-stimulated duodenal bicarbonate secretion and Isc in a concentration-dependent manner (from 10-8 to 10-5M) ( P < 0.05). PMA preincubation had no effects on carbachol- or heat-stable toxin-stimulated bicarbonate secretion. Western blot analysis revealed that PKCα, -γ, -ϵ, -θ, -μ, and -ι/λ were expressed in murine duodenal mucosa. Ro 31–8220 (an inhibitor active against PKCϵ, -α, -β, and -γ), but not Gö 6983 (an inhibitor active against PKCα, -γ, -β, and -δ), reversed the potentiating effect of PMA on db-cAMP-stimulated bicarbonate secretion. PMA also time- and concentration-dependently increased the activity of PKCϵ, an effect that was prevented by Ro 31–8220 but not Gö 6983. These results demonstrate that activation of PKC potentiates cAMP-stimulated duodenal bicarbonate secretion, whereas it does not modify basal secretion. The effect of PKC on cAMP-stimulated bicarbonate secretion is mediated by the PKCϵ isoform.

scholarly journals Sec1p directly stimulates SNARE-mediated membrane fusion in vitro

2004 ◽  
Vol 167 (1) ◽  
pp. 75-85 ◽  
Author(s):  
Brenton L. Scott ◽  
Jeffrey S. Van Komen ◽  
Hassan Irshad ◽  
Song Liu ◽  
Kirilee A. Wilson ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Membrane Fusion ◽  
Membrane Trafficking ◽  
Snare Complex ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Bud Neck ◽  
Precise Role

Sec1 proteins are critical players in membrane trafficking, yet their precise role remains unknown. We have examined the role of Sec1p in the regulation of post-Golgi secretion in Saccharomyces cerevisiae. Indirect immunofluorescence shows that endogenous Sec1p is found primarily at the bud neck in newly budded cells and in patches broadly distributed within the plasma membrane in unbudded cells. Recombinant Sec1p binds strongly to the t-SNARE complex (Sso1p/Sec9c) as well as to the fully assembled ternary SNARE complex (Sso1p/Sec9c;Snc2p), but also binds weakly to free Sso1p. We used recombinant Sec1p to test Sec1p function using a well-characterized SNARE-mediated membrane fusion assay. The addition of Sec1p to a traditional in vitro fusion assay moderately stimulates fusion; however, when Sec1p is allowed to bind to SNAREs before reconstitution, significantly more Sec1p binding is detected and fusion is stimulated in a concentration-dependent manner. These data strongly argue that Sec1p directly stimulates SNARE-mediated membrane fusion.

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