The Effect of Tanshinone-IIa on IL-1β Induced-Thrombocytosis in an Immune Vasculitis Model

Abstract Inflammation cytokines may be involved in the pathogenesis of thrombocytosis with vasculitis. Our previous study showed that inflammation cytokine IL-1β plays an important role on in-vitro megakaryopoiesis (Yang M et al, Br J Haematol 2000). The role of IL-1β and Tanshinone IIA (TIIA) (Isolated from Danshen, Radix Salviae Miltiorrhiza Bge) on platelets and megakaryocytes (MKs) in immune vasculitis model was investigated in this study. Rabbit model with immune vasculitis was established by injection (iv) of BSA. After treatment with BSA for 7 days, the platelet count, platelet aggregation and the expression of AnnexinⅤ were significantly increased in this vasculitis model group compared with normal control group (n=7). IL-1β levels was also significantly higher in vasculitis model. There were positive correlations between platelet count and IL-1β levels (R=0.65), platelet aggregation and IL-1β levels (R=0.60). Treatment with TIIA (5 mg/kg/day, iv) and aspirin significantly decreased all these parameters. MKs and CFU-MK number were also significantly increased in vasculitis group as compared to normal group. Treatment with TIIA and aspirin significantly reduced the number of MKs and CFU-MK in this model. Study further demonstrated that IL-1β alone or in combination with TPO induced in-vitro CFU-MK formation. The mRNA of of IL-1 type I and type II receptors (IL-1 RI and RII) were detected in cultured MK (CD61+ CD41+) cells. The expression of IL-1 RI and RII was also confirmed by immunofluorescence staining in bone marrow MKs. Moreover, the IL-1R bloker can reduced IL-1β induced megakaryopoiesis. TIIA on in-vitro megakaryopoiesis was also investigated. TIIA at 10-30 ug/ml significantly inhibited CFU-MK formation. TIIA also induced the apoptosis of MKs in a dose dependent manner by Anexin V assay. Caspase 3 assay showed the activation of Caspase 3 increased from 5% to 16%. Using JC-1 assay found that the depolarized cells increased from 9% to 17% suggesting the involvement of intrinsic apoptotic pathway. IL-1β may play an important role in the thrombocytosis of immune vasculitis by inducing megakaryopoiesis. TIIA has anti-platelet effect in this model which may be mediated via inhibiting IL-1β induced-megakaryopoiesis. Disclosures No relevant conflicts of interest to declare.

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IL-1β Plays An Important Role On Thrombocytosis In An Immune Vasculitis Model Via Promoting Megakaryopoiesis

Blood ◽

10.1182/blood.v122.21.2325.2325 ◽

2013 ◽

Vol 122 (21) ◽

pp. 2325-2325

Author(s):

Mo Yang ◽

Min Zhou ◽

Su yi Li ◽

Beng Chong ◽

Xiao jing Li

Keyword(s):

Bone Marrow ◽

Platelet Count ◽

Platelet Aggregation ◽

Conflicts Of Interest ◽

Serum Levels ◽

Control Group ◽

Type I ◽

Anti Inflammation ◽

Immune Vasculitis

Abstract Thrombocytosis and inflammation cytokines may be involved in the pathogenesis of vasculitis. Our previous study have showed that major inflammation cytokine IL-1β play an important role on in-vitro megakaryopoiesis (Yang M et al, Br J Haematol 2000). In this study, we investigated the changes of IL-1β and megakaryopoiesis and the effect of aspirin in an immune vasculitis model. Rabbit immune vasculitis model was established by intravenous injection of bovine serum albumin. In this model, platelet number and function of periphery blood, megakaryocyte number and the CFU-MK formation of the bone marrow, and serum levels of inflammatory cytokines were investigated. After treatment with BSA for 7 days, the platelet count, platelet aggregation and the expression of AnnexinⅤ were significantly increased in this vasculitis model group compared with normal control group (n=6). The serum levels of inflammatory cytokine IL-1β was also significantly higher in vasculitis model. There were positive correlations between platelet count and IL-1β levels (R=0.55), platelet aggregation and IL-1β levels (R=0.603). Treatment with aspirin (100 mg/kg/d) significantly decreased all these parameters, showing aspirin had anti-platelets and anti-inflammation effects. Our results also demonstrated that megakaryocyte number and the formation of CFU-MK were significantly increased in vasculitis group as compared to those in normal group. Treatment with aspirin significantly reduced the number of megakaryocytes and the formations of CFU-MK in bone marrow in this immune vasculitis model. Our study further demonstrated that IL-1β alone or in combination with TPO induced in-vitro CFU-MK formation. Using RT-PCR techniques, the mRNA of of IL-1 type I and type II receptors (IL-1 RI and RII) were detected in cultured CD61+ CD41+ cells and four megakaryocytic cell lines. The expression of IL-1 RI and RII was also confirmed by flow cytometry and immunofluorescence staining in bone marrow megakaryocytes. Moreover, the IL-1R bloker can reduced IL-1β induced megakaryopoiesis. This sudy showed that IL-1β may play an important role in the pathogenesis of immune vasculitis. Aspirin has anti-inflammation effects in this model which may be mediated via inhibiting megakaryopoiesis and platelet formation. Disclosures: No relevant conflicts of interest to declare.

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Tanshinone IIA has anti-platelet effect and induces apoptosis in megakaryocytes via TNFR and Caspases

Blood ◽

10.1182/blood.v122.21.3635.3635 ◽

2013 ◽

Vol 122 (21) ◽

pp. 3635-3635 ◽

Cited By ~ 1

Author(s):

Mo Yang ◽

Fu qun Wu ◽

Min Zhou ◽

Jie yu Ye ◽

Xiao jing Li ◽

...

Keyword(s):

Platelet Count ◽

Molecular Mechanisms ◽

Caspase 3 ◽

Conflicts Of Interest ◽

Rabbit Model ◽

Tanshinone Iia ◽

Differentially Expressed ◽

Dependent Manner ◽

Apoptotic Pathway ◽

Immune Vasculitis

Abstract Tanshinone IIA (TIIA) isolated from Danshen (Radix Salviae Miltiorrhiza Bge) is a derivative of phenanthrenequinone, which has been used for centuries to treat hypercoagulation related diseases. Our previous study showed that TIIA has neural protective effect (Xia et al, Pediatric Research, 2005). In this study, we investigated the effect of TIIA on platelets and megakaryocytes in a rabbit model, and its molecular mechanisms. Rabbit immune vasculitis model was established by intravenous injection of bovine serum albumin with TIIA treatment (5 mg/kg/day, iv). The platelet count, platelet aggregation, and inflammatory cytokine IL-1β level were significantly increased in vasculitis model compared with normal group at day 7. There were positive correlations between platelet count and IL-1β level. The number of megakaryocytes and CFU-MK formation in bone marrow were significantly increased in this model. Treatment with TIIA significantly decreased all these parameters, and also significantly reduced the injury vessel in immune vasculitis. Furthermore, the effect of IIA on in-vitro megakaryopoiesis was investigated. TIIA at 10-30 ug/ml significantly inhibited CFU-MK formation (p<0.05, n=6). TIIA also induced the apoptosis of megakaryocytic cell line CHRF. The cell viability was reduced to 81% after 72hrs of TIIA treatment. Using Annexin V/PI staining, TIIA induced apoptosis on CHRF cells in a dose dependent manner. This was verified by Caspase 3 assay which showed the activation of Caspase 3 increased from 5% to 16% after TIIA treatment. Using JC-1 assay, we found that the depolarized cells increased from 9% to 17% after TIIA treatment suggesting the involvement of intrinsic apoptotic pathway. To further determine the molecular mechanisms involved in the pro-apoptosis effect, Microarray studies using Affymetrix 133 plus genechips were conducted to identify the genes that were differentially expressed after TIIA treatment. Several groups of genes involved in apoptosis, calcium regulation and cell cycle checkpoints were found to be differentially expressed after the treatment. The differential expressions of these genes were validated using quantitative PCR. The most significantly upregulated gene (6.0±0.333 folds) was TNF Receptor Super-Family 9 (TNFRSF9). In addition, Receptor Interacting Protein Kinase (RIPK), a protein that likely interacts with TNFRSF9, was up-regulated to 2.0±0.167 folds. These results suggest that TIIA has an anti-platelet effect in this model. Its mechanism may be related to its inhibiting megakaryopoiesis and inducing apoptosis of megakaryocytes via TNFR and caspases. Disclosures: No relevant conflicts of interest to declare.

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Toxicity Effects of Methylene Blue on Rat Intervertebral Disc Annulus Fibrosus Cells

January 2018 - Pain Physician ◽

10.36076/ppj/2019.22.155 ◽

2019 ◽

Vol 2 (22.2) ◽

pp. 155-164

Author(s):

Liang Zhang

Keyword(s):

Methylene Blue ◽

Cell Apoptosis ◽

Annulus Fibrosus ◽

Caspase 3 ◽

In Vitro Study ◽

Collagen Type I ◽

Type I ◽

Dependent Manner ◽

Concentration Dependent Manner

Background: There is an increasing local application of methylene blue (MB) in the treatment of discogenic low back pain (LBP) and percutaneous transforaminal endoscopic discectomy (PTED) procedures. MB could generate DNA damage and induce apoptosis in different cell types; however, the effects of MB on intervertebral disc (IVD) annulus fibrosus (AF) cells are not clearly understood. Objective: The objective of this study was to investigate the effects of different concentrations of MB on rat AF cells in vitro. Study Design: This study used an experimental design. Setting: This research was conducted at the Orthopaedic Institute of the Clinical Medical College of Yangzhou University. Methods: AF cells were isolated and cultured with different concentrations of MB (0, 2, 20, and 200 μg/mL) and assessed to determine the possible cytotoxic effects of MB. The cell proliferation was detected by Cell Counting Kit-8 (CCK-8) assay. The inverted phase-contrast microscopy was used to perform morphological observation of apoptotic cells, and flow cytometry was used to measure the incidence of cell apoptosis. The mRNA and protein expression levels of apoptosis-associated genes (caspase-3, Bcl-2, and Bax) and other related genes (collagen type I, transforming growth factor β1 [TGF-β1], fibroblast growth factor [bFGF], and tissue inhibitor of metalloproteinase-1 [TIMP-1]) were analyzed by quantitative real-time PCR (RT-PCR) and Western blotting. Results: Our results indicated that MB reduced cell viability in a concentration- and timedependent manner. MB also induced marked AF cell apoptosis in a concentration-dependent manner observed by inverted phase-contrast microscopy, flow cytometry, and indicated by the increased expression of caspase-3. Both RT-PCR and Western blotting revealed significant upregulation of Bax and caspase-3 expression levels accompanied by decreased expression of Bcl2 in a concentration-dependent manner. Moreover, collagen type I, TGF-β1, bFGF, and TIMP-1 mRNA and protein levels were also found to be decreased by MB in a concentration-dependent manner. Limitations: Limitations of this study were the in vitro study design and lack of in vivo validation of the observed effects of MB on human IVD cells. Conclusions: Our results indicate that a high concentration of MB can not only inhibit proliferation and paracrine function of AF cells, but can also induce cell apoptosis in a concentration-dependent manner, suggesting that it is necessary to choose low concentrations of MB in practical application and limit the use of MB in the treatment of discogenic LBP to research protocols. Key words: Methylene blue, annulus fibrosus cell, proliferation, apoptosis, paracrine

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Phosphatidylinositol-3,4-Bisphosphate-Akt Signaling Pathway Promotes Platelet Activation

Blood ◽

10.1182/blood-2018-99-115066 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 1131-1131

Author(s):

Jasna Marjanovic ◽

Brad Rumancik ◽

Luke Weber ◽

Felix Wangmang ◽

Dane Fickes ◽

...

Keyword(s):

Platelet Aggregation ◽

Platelet Activation ◽

Conflicts Of Interest ◽

Glycogen Synthase ◽

Thrombus Formation ◽

Type I ◽

Dependent Manner ◽

Wild Type ◽

Phosphorylated Akt

Abstract Phosphatidylinositol-3,4-bisphosphate (PtdIns(3,4)P2) is a messenger that accumulates in platelets in a phosphoinositide 3-kinase and platelet aggregation-dependent manner. PtdIns(3,4)P2 is broken down by inositol polyphosphate 4-phosphatases, type I (INPP4A) and type II (INPP4B). These enzymes do not catalyze hydrolysis of phosphoinositides other than PtdIns(3,4)P2, and therefore provide unique means for studying the role of this lipid in platelet activation. We have found that the dominant isoform of 4-phosphatases expressed in platelets is INPP4A and we have generated radiation chimera mice with the deficiency in INPP4A restricted to hematopoietic cell lineage. Compared to wild type platelets, agonist-stimulated INPP4A-deficient platelets accumulated higher levels of PtdIns(3,4)P2. An increase in platelet aggregation in INPP4A-deficient platelets was observed with all tested agonists. To study platelet function in vivo, we performed carotid artery injury mouse thrombosis model experiments. Time to occlusion was dramatically reduced in mice with INPP4A deficiency. These data support the hypothesis that by regulating PtdIns(3,4)P2 levels, INPP4A downregulates platelet aggregation and thrombus formation. To investigate mechanisms mediating INPP4A-dependent signals, we compared levels of phosphorylated Akt and phosphorylated glycogen synthase kinase (GSK) in wild type and INPP4A-deficient platelets in response to agonist stimulation. An increase in phospho-Akt levels was observed in INPP4A-deficient platelets, suggesting that in addition to its well-characterized regulator, PtdIns(3,4,5)P3, PtdIns(3,4)P2 can promote Akt activation. Interestingly, this was not accompanied by a significant increase in phospho-GSK levels, suggesting a possible novel mechanism involved in platelet aggregation. Disclosures No relevant conflicts of interest to declare.

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In Vitro Characterization of Platelet Dysfunction In Common Hematological Disorders Using the Verify Now® Assay

Blood ◽

10.1182/blood.v116.21.1436.1436 ◽

2010 ◽

Vol 116 (21) ◽

pp. 1436-1436

Author(s):

Nina D’Abreo ◽

Vatsala Kirtani ◽

Jennifer L. Kujawa Eisenstein ◽

Yelda Nouri ◽

Matt Geller ◽

...

Keyword(s):

Platelet Count ◽

Platelet Aggregation ◽

Platelet Function ◽

Conflicts Of Interest ◽

Reference Ranges ◽

Platelet Dysfunction ◽

Platelet Defects ◽

Verify Now ◽

Instructions For Use

Abstract Abstract 1436 Objectives: Myelodysplastic syndrome (MDS), immune thrombocytopenia purpura (ITP) and myeloproliferative disorders (MPD) are frequent diagnoses in a community hematology practice. Qualitative platelet defects are common features of these disorders but are difficult to characterize in daily practice as specialized technology is not readily available. The Verify Now® (VN) is a rapid, point-of service assay to measure platelet aggregation. VN assesses the degree of inhibition of GPIIb/IIIa mediated aggregation and uses minimal sample preparation. Its main application currently, is to determine the adequacy of anti-platelet therapy with aspirin (ASA), thienopyridines, such as clopidogrel (CPL), and GPIIb/IIIa inhibitors in patients with cardiovascular disease. (Verify Now for IIb/IIIa, aspirin, and P2Y12, Instructions for Use, Accumetrics) We used VN to detect platelet aggregation defects in patients with ITP, MDS and MPD and compared the to a platelet function analyzer PFA -100. (Francis JL; In Michelson AD, ed. Platelets, 2nded. San Diego: Elsevier/Academic Press, 2007:535-544) Methods: Subjects with MDS, ITP, and MPD were identified from our Hematology practice. Informed consent was obtained from all patients. Patients taking aspirin and /or clopidogrel were not excluded. Platelet function was determined concurrently using VN and PFA-100 using standard reference ranges. (Verify Now for IIb/IIIa, aspirin, and P2Y12, Instructions for Use, Accumetrics), (Mammen EF et al; Semin Throm Hemost. 1998; 24 (2):195-205). Results: Thirty three patients are enrolled in the study, 21 with ITP, 6 with MDS and 6 with MPD. Assay results are available for 30 patients. Platelet counts for all patients ranged from 2 to 1206 ×103/cmm, mean platelet count being 184 ×103/cmm (SD ± 215) and median count was 120 ×103/cmm. ITP: In 15 patients with ITP and platelet count ≥ 100 ×103/cmm, 11 were not on ASA/CPL. PFA-100 and VN each detected abnormalities in 4 patients but results were non-concordant in 2 patients. In 4 patients on ASA, VN detected ASA effect in all 4 whereas the PFA-100 detected 2. In 2 patients with platelet count < 100 ×103/cmm not on ASA/CPL, VN detected abnormalities in both, whereas PFA detected only 1. (Table 1) MDS: Two patients had counts ≥ 100 ×103/cmm. One was on ASA and both assays detected ASA effect. Neither assay detected an abnormality in the patient not on ASA. In 4 patients with counts <100 ×103/cmm, 3 were not on ASA/ CPL. Both assays detected abnormalities in all 3 and ASA effect in 1 patient on ASA. (Table 2) MPD: In 4 patients with counts < 400 ×103/cmm, not on ASA/CPL, both assays detected non-concordant abnormalities in 1 patient. Both assays detected CPL and ASA effect in 1 patient taking both drugs. 2 patients had count ≥400,000. In 1 patient taking CPL, VN detected CPL effect but PFA did not. In 1 patient on ASA, PFA detected abnormality but VN did not. (Table 3) Conclusion: In patients with MDS, ITP, and MPD, abnormal platelet function is common. These results show that VN may be as sensitive for detecting platelet dysfunction as PFA-100. Results were especially concordant in MDS patients. We plan to include 150 patients to confirm these results. We hope to define qualitative platelet defects in this population so that appropriate intervention can be recommended prior to invasive procedures. Disclosures: No relevant conflicts of interest to declare.

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Arsenic Trioxide Induces Platelet Apoptosis

Blood ◽

10.1182/blood.v120.21.5149.5149 ◽

2012 ◽

Vol 120 (21) ◽

pp. 5149-5149

Author(s):

Yicun Wu ◽

Jin Dai ◽

Weilin Zhang ◽

Rong Yan ◽

Changgeng Ruan ◽

...

Keyword(s):

Flow Cytometry ◽

Western Blot ◽

Arsenic Trioxide ◽

Caspase 3 ◽

Conflicts Of Interest ◽

Pulmonary Haemorrhage ◽

Tumour Cells ◽

Dependent Manner ◽

Platelet Apoptosis

Abstract Abstract 5149 Objective: Arsenic trioxide, a component of Traditional Chinese Medicine, is known as an effective anticancer drug especially in the treatment of acute promyelocytic leukaemia (APL). APL has emerged as the most curable subtype of acute myeloid leukaemia since the widely use of arsenic trioxide-based chemotherapy. However, recent researches show that thrombocytopenia occurred in 79% of the relapsed or refractory APL patients treated with arsenic trioxide, and part of the APL patients had to be stopped treatment because of catastrophic bleeding, such as intracranial and pulmonary haemorrhage. Thrombocytopenia also occurred in 43% of the myelodysplastic syndrome patients treated with arsenic trioxide. Recently, arsenic trioxide has been proved to have a pro-apoptotic effect on various kinds of nucleated tumour cells or non-tumour cells. The effect of arsenic trioxide on enucleated platelet, however, still remains unclear. The aim of current study is to investigate whether arsenic trioxide induces platelet apoptosis. Methods: Washed platelets (3 × 108/ml) were incubated with different concentrations of arsenic trioxide or vehicle at 37°C for 4 hours. Then, mitochondrial inner transmembrane potential (ΔΨm) and phosphatidylserine (PS) exposure were tested by flow cytometry. In the mean time, the treated platelets were analyzed by western blot for the expression levels of pro-apoptotic protein (Bax), and anti-apoptotic proteins (Bcl-2 and Bcl-XL). Activation of caspase-3 was also examined by western blot using an anti-caspase-3 antibody. Results: ΔΨm depolarization and PS exposure were dose-dependently induced in platelets incubated with different concentrations (2 uM, 4 uM, 8 uM, 16 uM) of arsenic trioxide as detected by flow cytometry, and the lowest concentration of arsenic trioxide incurring ΔΨm depolarization and PS exposure was 4 umol/L. Simultaneously, arsenic trioxide induced up-regulation of Bax and down-regulation of Bcl-2 and Bcl-XL in a dose-dependent manner. Furthermore, 17 kD cleaved caspase-3 fragments were dose-dependently induced in platelets treated with different concentrations of arsenic trioxide indicating that caspase-3 was activated by arsenic trioxide. Conclusions: Taken together, the data indicate that arsenic trioxide induces platelet apoptosis in vitro, which might suggest a novel pathogenic mechanism of thrombocytopenia in the patients who treated with arsenic trioxide. Disclosures: No relevant conflicts of interest to declare.

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Anti-Apoptotic Effect of Angelica Polysaccharide (APS) on Cryopreservation of Platelets

Blood ◽

10.1182/blood-2021-151963 ◽

2021 ◽

Vol 138 (Supplement 1) ◽

pp. 3250-3250

Author(s):

Mo Yang ◽

Weiqing Su ◽

Liuming Yang ◽

Huimin Kong ◽

Huiling Wei ◽

...

Keyword(s):

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Caspase 3 ◽

Conflicts Of Interest ◽

Annexin V ◽

Control Group ◽

Apoptotic Effect ◽

Vitro Effect

Abstract Background: Angelica Polysaccharide (APS) is from the root of Radix Angelicae Sinensis (Danggui). Danggui has been used for centuries to treat blood-deficiency related diseases. The hematopoietic effect of Danggui may be related to its constituent, polysaccharide. The effects of angelica polysaccharide on cryopreservation of platelets and megakaryocytes have not been well studied. This study focused on anti-apoptotic effect of APS and TPO on cryopreservation of platelets and megakaryocytes and provided new methods for prolonging the preservation time of platelets in vitro. Methods: The expression of platelet membrane glycoprotein CD41 and CD61, as well as the platelet apoptotic rate, Caspase 3 expression and mitochondrial membrane potential (MMP) were detected by flow cytometry; the anti-apoptotic mechanism of APS by PI3K /AKT signaling pathway was analyzed by Western blot assay. CFU assays were used to determine the effects of APS on megakaryocytic progenitor cells. Analyses of Annexin V, Caspase-3, and Mitochondrial Membrane Potential were conducted in megakaryocytic cell line M-07e. The effects of APS on cells treated with Ly294002, PI3K inhibitor and the effect of APS on the p-AKT were also studied. Results: The platelets were divided into 4 group: control group (4 ℃ stored platelets), APS group (APS-treated platelets stored at 4 ℃), LY294002 group (LY294002-treated platelets stored at 4 ℃) and LY294002+APS group (LY294002+APS treated platelets stored at 4 ℃). The apoptotic rate of platelets in LY294002 group was obviously increased. Compared with control group, the expression of CD41 and CD61 gradually decreased along with the enhancement of LY294002 concentrations (r=-0.953). The apoptotic rate of platelets in LY294002 group was enhanced significantly (P<0.05). While in LY294002+APS group, the apoptotic rate of platelets was significantly reduced (P<0.05) as compare with LY294002 group, which suggest that APS has an anti-apoptotic effect on the cryopreserved platelets. APS decreased the expression of Caspase-3 and inhibited the reduction of mitochondrial membrane potential induced by LY294002. Moreover, APS increased the activation of PI3K /AKT pathway in Platelets . We further analyzed the in vitro effect of APS on CFU-MK formation. APS (50 ug/ml) enhanced TPO (50 ng/ml) -induced CFU-MK formation (p=0.06, n=4). APS also significantly enhanced PDGF, bFGF and VEGF-induced CFU-MK formation (n=4). Moreover, the anti-apoptotic effect of APS in M-07e cells was also demonstrated by Annexin-V, Caspase-3, and JC-1 assays. Adding LY294002 alone increased the percentage of cells undergoing apoptosis. However, additional of APS to LY294002-treated cells reversed the percentage of cells undergoing apoptosis. Furthermore, addition of APS significantly increased the p-AKT. Conclusion: APS, like TPO, has an anti-apoptotic effect on the cryopreserved platelets and megakaryocytes through activating PI3K/AKT, decreasing the expression of Caspase-3 and inhibiting the reduction of MMP. Disclosures No relevant conflicts of interest to declare.

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Effects of Pentoxifylline on Peritoneal Fibroblasts and Silica-Induced Peritoneal Fibrosis

Peritoneal Dialysis International ◽

10.1177/089686080302300303 ◽

2003 ◽

Vol 23 (3) ◽

pp. 228-236 ◽

Cited By ~ 16

Author(s):

Cheng-Chung Fang ◽

Ming-Nan Lai ◽

Chiang-Ting Chien ◽

Kuan-Yu Hung ◽

Chien-Chen Tsai ◽

...

Keyword(s):

Body Weight ◽

Collagen Synthesis ◽

Control Group ◽

Type Iii Collagen ◽

Type I ◽

Dependent Manner ◽

Peritoneal Fibrosis ◽

Group 1

♦ Background Peritoneal fibrosis is a long-term complication following continuous ambulatory peritoneal dialysis (CAPD). Peritoneal fibroblasts may play an important role in peritoneal fibrosis. Up to now, the treatment of peritoneal fibrosis in patients with CAPD remains unsatisfactory. Pentoxifylline (PTX) is a xanthine derivative and is used in the treatment of peripheral vascular and cerebrovascular diseases. Several studies have demonstrated that PTX can ameliorate fibrosis of the skin, liver, and kidney. ♦ Objective To investigate the effect of PTX on in vitro growth and collagen synthesis of human peritoneal fibroblasts (HPFBs), and to evaluate the effects of PTX on silica-induced peritoneal fibrosis in vivo. ♦ Design and Measurements In the in vitro study, HPFBs were cultured from human omentum. The effect of PTX on the growth of serum-stimulated HPFBs was evaluated by MTT assay. The effect of PTX on the collagen synthesis of HPFB was measured by [3H]-proline incorporation. Expression of type I and type III collagen mRNA was evaluated by Northern blotting. The effects of PTX on matrix metalloproteinase (MMP) activity and cAMP level in HPFBs were measured by immunoassays. In the in vivo study, Wistar rats were randomly divided into five groups. All rats received intraperitoneal (IP) injection of silica suspension (250 mg/100 g body weight) on day 0. The rats of group 1 (control group) were injected with vehicle IP every day for 14 days. The rats of groups 2, 3, and 4 were injected with PTX (4 mg/100 g body weight) IP every day for 3, 7, and 14 days, respectively. The rats in group 5 received an intravenous infusion of PTX (8 mg/100 g body weight) every day for 7 days. On the 15th day after silica injection, all rats were sacrificed. Their parietal and visceral peritoneums were removed and processed for pathology, and the severity of fibrosis was measured and scored. ♦ Results: In vitro, PTX inhibited serum-stimulated HPFB growth (maximum was 93% at 1 mg PTX/mL) in a dose-dependent manner. Collagen synthesis by HPFB was reduced (47% at 1 mg PTX/mL), and collagen I and III mRNA expression in HPFBs was suppressed by PTX. The PTX did not affect the MMP (including MMP-1, MMP-8, and MMP-13) activities of HPFBs. The mechanism of PTX was through increasing cAMP by its phosphodiesterase inhibiting activity. In vivo, the severity of fibrosis was significantly reduced in groups 4 and 5 compared to group 1 ( p < 0.05). ♦ Conclusion These results suggest that PTX can inhibit growth of and collagen synthesis by HPFBs in vitro. The fibrosis derived from silica-induced peritonitis in vivo was also ameliorated by PTX. Therefore, pentoxifylline may have the potential to be used to treat peritoneal fibrosis in patients on CAPD.

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The Study of Effect and Mechanism by Vitamin K2 on Human MDS Cell Line MUTZ-1.

Blood ◽

10.1182/blood.v108.11.4357.4357 ◽

2006 ◽

Vol 108 (11) ◽

pp. 4357-4357

Author(s):

Bao-An Chen ◽

Xin Xu ◽

Ze-Ye Shao ◽

Jia-Hua Ding ◽

Guo-Hua Xia ◽

...

Keyword(s):

Cell Cycle ◽

Cell Line ◽

Caspase 3 ◽

Cellular Proliferation ◽

Vitamin K2 ◽

Time Dependent ◽

Control Group ◽

Dependent Manner ◽

Significant Difference

Abstract The myelodysplastic syndromes (MDS) are characterized by hemopoietic insufficiency associated with cytopenias leading to serious morbidity and the additional risk of leukemic transformation. Vitamin K2(VK2) is reported to induce apoptosis or differentiation of leukemic cell lines in vitro. For investigating the effects and mechanism of VK2 on human MDS cell line MUTZ-1 in vitro,we observed the changes of morphologic features of MUTZ-1 cells by exposing to VK2.The transmission electron microscope was used to observe the apoptosis of MUTZ-1 cells. Cellular proliferation was determined by the MTT assay. The flow cytometry was used to analysis apoptosis rate and the change of cell cycle. The expression of apoposis-related genes bcl-2, survivin and bax were detected by reverse transcriptase polymerase chain reaction(RT-PCR).The activity of caspase-3 was detected by chemiluminescence assay. After exposing to 10μmol L−1 and higher concentration of VK2, it could inhibit MUTZ-1 cells proliferation in a dose-and time-dependent manner(p<0.05). At concentration of 5μmol/l VK2 treatment, it might accelerate cellular proliferation, but there’s no significant difference compared with control group. Apoptosis peak on FCM and positive Annexin-V FITC/PI on cell membrane showed that VK2 induced apoptosis of MUTZ-1 cells in a dose-and-time-dependent manner, G0/G1 cell cycle arrest, significantly dow-regulated the expression of bcl-2 and survivin, but had no effect on the expression of bax.The activities of caspase-3 were significantly increased. Low concentration of VK2 could facilitate cell proliferation. The higher concentration of VK2 could induce apoptosis of MUTZ-1 cells. These results indicate that VK2 induces MUTZ-1 cells apoptosis by activating caspase-3 pathway, the apoptosis related genes bcl-2, survivin down-regulated might play an important role in this process.

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Fucoidan Is a Novel Platelet Agonist for CLEC-2 Receptor

Blood ◽

10.1182/blood.v120.21.94.94 ◽

2012 ◽

Vol 120 (21) ◽

pp. 94-94

Author(s):

Bhanukanth Manne ◽

Todd M Getz ◽

Craig Hughes ◽

Carol T Dangelmaier ◽

Steve P Watson ◽

...

Keyword(s):

Platelet Aggregation ◽

Animal Models ◽

Platelet Activation ◽

Conflicts Of Interest ◽

Human Platelets ◽

Lag Phase ◽

Dependent Manner ◽

Wild Type ◽

Concentration Dependent Manner

Abstract Abstract 94 Fucoidan, a sulphated polysaccharide from fucus vesiculosus, decreases bleeding time and clotting time in hemophilia, possibly through inhibition of tissue factor pathway inhibitor (TFPI) (Prasad et al., Blood 111:672, 2008). The decrease in bleeding times in the hemophilia animal models by in vivo administration of fucoidan suggests the beneficial effect of fucoidan as a novel treatment. Furthermore, in vitro studies using platelet poor plasma from hemophilia animal models and human patients has shown that fucoidan inhibits TFPI thereby contributing to an increase in the extrinsic coagulation pathway activity. The effect of fucoidan on platelets however has not been studied. As it is known that the platelet count remains unaffected in hemophilia A patients and bleeding times are primarily measured to assess normal platelet function, we hypothesize that the decrease in bleeding times in the hemophilia animal models may be due to platelet activation by fucoidan. In this study, we demonstrate for the first time that fucoidan induces platelet activation in a concentration dependent manner. Fucoidan-induced platelet activation is completely abolished by the pan-Src family kinase (SFK) inhibitor, PP2, and in the absence of Syk and PLC-g2. Furthermore, fucoidan-induced platelet activation has a lag phase, which is reminiscent of platelet activation by collagen and by CLEC-2 receptor agonists. Platelet activation by fucoidan however was only slightly inhibited in FcRg-chain null mice indicating that fucoidan is not acting primarily through GPVI receptor. On the other hand, fucoidan-induced platelet activation was inhibited in CLEC-2 deficient mouse platelets revealing CLEC-2 as a physiological target of fucoidan. Thus, our data shows fucoidan as a novel CLEC-2 receptor agonist that activates platelets through an SFK-dependent signaling pathway. Further, the efficacy of fucoidan in hemophilia raises the possibility that decreased bleeding times could be achieved through activation of platelets. A) Fucoidan induces platelet activation: Washed aspirin-treated human platelets were stimulated with increasing concentrations of fucoidan at 37°C. Platelet aggregation was measured using a Lumi-aggregometer. The tracings are representative of data from at least three independent experiments. B) Effect of SFK inhibition on fucoidan-induced platelet activation: Washed aspirin-treated human platelets were pre-treated with SFK inhibitor PP2 10uM or PP3 (vehicle) at 37°C for 5 min followed by stimulation with fucoidan (50 ug/ml) for 3 minutes under stirred conditions. Platelet aggregation was measured using Lumi-aggregometer and effect on phosphorylation of Syk (Y525/26) and LAT (Y191) in the presence of SFK inhibitor PP2 an PP3 (control) were analyzed. The results are representative of data from platelets at least three independent experiments. C) Identifying a possible receptor for fucoidan on platelets: Wild type, FcRg-chain or CLEC-2 null murine platelets were stimulated with fucoidan (50 ug/ml) at 37°C under stirred conditions and aggregation was measured using Lumi-aggregometer. A) Fucoidan induces platelet activation: Washed aspirin-treated human platelets were stimulated with increasing concentrations of fucoidan at 37°C. Platelet aggregation was measured using a Lumi-aggregometer. The tracings are representative of data from at least three independent experiments. . / B) Effect of SFK inhibition on fucoidan-induced platelet activation: Washed aspirin-treated human platelets were pre-treated with SFK inhibitor PP2 10uM or PP3 (vehicle) at 37°C for 5 min followed by stimulation with fucoidan (50 ug/ml) for 3 minutes under stirred conditions. Platelet aggregation was measured using Lumi-aggregometer and effect on phosphorylation of Syk (Y525/26) and LAT (Y191) in the presence of SFK inhibitor PP2 an PP3 (control) were analyzed. The results are representative of data from platelets at least three independent experiments. . / C) Identifying a possible receptor for fucoidan on platelets: Wild type, FcRg-chain or CLEC-2 null murine platelets were stimulated with fucoidan (50 ug/ml) at 37°C under stirred conditions and aggregation was measured using Lumi-aggregometer. Disclosures: No relevant conflicts of interest to declare.

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