OBJECTIVE: To investigate the effect of 5-hydroxytryptamine (5-HT) on the proliferation, apoptosis and colony-forming unit-megakaryocyte (CFU-MK) of Meg-01 cells and its possible mechanisms. METHODS: The uptake and metabolism of 5-HT in Meg-01 cells were analysed by reverse-phase high-performance liquid chromatography (RP-HPLC) with electrochemical detection. The expression of 5-HT2B receptor (5-HT2BR) in megakaryocytes was detected by immunofluorescence staining. The cell proliferation and viability were measured by MTT and Trypan blue staining after Meg-01 cells were single-cultured or co-cultured with different concentrations of 5-HT/5-HT2BR inhibitor Ketanserin for 48 h. Meg-01 cells were incubated with 5-HT/ Ketanserin for 72 h, then the flow cytometry was used to detect early apoptosis of the cells and the activity of caspase-3. Using CFU-MK assay to investigate the effect of 5-HT on the differentiation of megakaryocytes. RESULTS: 5-HT could be uptaken by Meg-01 cells, and metabolized into 5-hydroxyindoleacetic acid (5-HIAA). The expression of 5-HT2BR on megakaryocytes could be detected after immunofluorescence staining. 5-HT could promote the proliferation of Meg-01 cells at a dose-dependent manner (r =0.82), with the most significant effect observed at a concentration of 200 nmol/L (P < 0.001). Trypan blue staining also indicated that 200 nmol/L 5-HT had the most significant effect on the viability of Meg-01 cells (P < 0.05). The proliferation of Meg-01 cells treated with 5-HT was increased compared with the untreated control (P < 0.001), while the combination of 5-HT with ketanserin downregulated this effect. 5-HT significantly reduced the early apoptosis rate (P < 0.001) and caspase-3 activity (P < 0.05) of Meg-01 cells, while addition of ketanserin significantly increased the early apoptosis rate of Meg-01 cells (P < 0.001) and caspase-3 activity also increased to some extent. 5-HT promoted the formation of CFU-MK in bone marrow cells in a dose-dependent manner (r =0.89). The addition of ketanserin reduced the promoting effect of 5-HT on CFU-MK formation (P < 0.01). CONCLUSION There may be monoamine oxidase present in megakaryocytes, which can metabolize and decompose 5-HT into 5-HIAA. 5-HT may promote the proliferation and differentiation of megakaryocytes through 5-HT2BR. Besides, 5-HT can also reduce the apoptosis of megakaryocytes, and its anti-apoptotic effect may be mediated by 5-HT2BR and caspase-3 pathways.
Apoptosis/drug effects* ; Cell Proliferation/drug effects* ; Megakaryocytes/metabolism* ; Serotonin/pharmacology* ; Humans ; Receptor, Serotonin, 5-HT2B/metabolism* ; Caspase 3/metabolism* ; Cell Differentiation

Abivertinib, a third-generation tyrosine kinase inhibitor, is originally designed to target epidermal growth factor receptor (EGFR)-activating mutations. Previous studies have shown that abivertinib has promising antitumor activity and a well-tolerated safety profile in patients with non-small-cell lung cancer. However, abivertinib also exhibited high inhibitory activity against Bruton's tyrosine kinase and Janus kinase 3. Given that these kinases play some roles in the progression of megakaryopoiesis, we speculate that abivertinib can affect megakaryocyte (MK) differentiation and platelet biogenesis. We treated cord blood CD34⁺ hematopoietic stem cells, Meg-01 cells, and C57BL/6 mice with abivertinib and observed megakaryopoiesis to determine the biological effect of abivertinib on MK differentiation and platelet biogenesis. Our in vitro results showed that abivertinib impaired the CFU-MK formation, proliferation of CD34⁺ HSC-derived MK progenitor cells, and differentiation and functions of MKs and inhibited Meg-01-derived MK differentiation. These results suggested that megakaryopoiesis was inhibited by abivertinib. We also demonstrated in vivo that abivertinib decreased the number of MKs in bone marrow and platelet counts in mice, which suggested that thrombopoiesis was also inhibited. Thus, these preclinical data collectively suggested that abivertinib could inhibit MK differentiation and platelet biogenesis and might be an agent for thrombocythemia.
Acrylamides/pharmacology* ; Animals ; Blood Platelets/drug effects* ; Cell Differentiation ; Megakaryocytes/drug effects* ; Mice ; Mice, Inbred C57BL ; Piperazines/pharmacology* ; Pyrimidines/pharmacology*

OBJECTIVETo investigate the effects of panaxadiol saponins component (PDS-C) isolated from total saponins of panax ginseng on proliferation, differentiation and corresponding gene expression profile of megakaryocytes.

METHODSBone marrow culture of colony forming assay of megakaryocytic progenitor cells (CFU-MK) was observed for the promoting proliferation mediated by PDS-C, and differentiation of megakaryocytic blasts caused by PDS-C was analyzed with flow cytometry in CHRF-288 and Meg-01 cells, as well as proliferation, differentiation-related genes expression profile and protein expression levels were detected by human gene expression microarray and western blot.

RESULTSIn response to PDS-C 10, 20 and 50 mg/L, CFU-MK from 10 human bone marrow samples was increased by 28.9%±2.7%, 41.0%±3.2% and 40.5%±2.6% over untreated control, respectively (P <0.01, each). Flow cytometry analysis showed that PDS-C treated CHRF-288 cells and Meg-01 cells significantly increased in CD42b, CD41, TSP and CD36 positive ratio, respectively. PDS-C induced 29 genes up-regulated more than two-fold commonly in both cells detected by human expression microarray representing 4000 known genes. The protein expression levels of ZNF91, c-Fos, BTF3a, GATA-1, RGS2, NDRG2 and RUNX1 were increased with western blot in correspond to microarray results.

CONCLUSIONPDS-C as an effective component for hematopoiesis, play the role to enhance proliferation and differentiation of megakaryocytes, also up-regulated expression of proliferation, differentiation-related genes and proteins in vitro.

Blotting, Western ; Bone Marrow Cells ; cytology ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Colony-Forming Units Assay ; Drugs, Chinese Herbal ; pharmacology ; Flow Cytometry ; Gene Expression Profiling ; Ginsenosides ; pharmacology ; Humans ; Megakaryocytes ; cytology ; drug effects ; metabolism ; Patents as Topic ; Saponins ; pharmacology ; Stem Cells ; cytology ; drug effects ; Transcription Factors ; metabolism ; Up-Regulation ; drug effects ; genetics

OBJECTIVETo investigate the effect and mechanism of Factor Xa on the differentiation of Meg-01 cells into platelet-like particles.

METHODSThe Meg-01 cells were used as experimental object, Factor Xa was used as agonist. Cell proliferation was detected by CCK-8 assay. The viability of platelet-like particles was analyzed by AlamaBlue kit. MAPK/ERK pathway and PI3K/AKT pathway were assayed by Western blot. The expression of CD41b was analyzed by Western blot and flow cytometry. Cell cycle and apoptosis were detected by flow cytometry.

RESULTSThe Factor Xa (1 µg/ml) inhibited cell viability, induced apoptosis. Factor Xa triggered cell arrest at the G(2)/M stage and down-regulated the expression of SKP2. After Meg-01 cells were stimulated by Factor Xa, the expression of CD41b was up-regulated and the MAPK/ERK pathway and PI3K/AKT pathway were activated. The platelets-like particles stimulated by FXa activation were viable.

CONCLUSIONThe Factor Xa maybe display some effect on the differentiation of megakaryocytes into platelets.

Apoptosis ; Blood Platelets ; cytology ; drug effects ; Cell Cycle Checkpoints ; Cell Differentiation ; drug effects ; Cell Line ; Cell Proliferation ; Cell Survival ; Factor Xa ; pharmacology ; Humans ; MAP Kinase Signaling System ; Megakaryocytes ; cytology ; drug effects ; Phosphatidylinositol 3-Kinases ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism

The association of thymoma with pure red cell aplasia has been well documented, but amegakaryocytic thrombocytopenia is not a recognized paraneoplastic syndrome complicating thymoma. We report a case of thymoma-complicated pure red cell aplasia and amegakaryocytic thrombocytopenia in a 73-yr-old woman. Pure red cell aplasia was diagnosed seven months after the detection of thymoma. One year after the diagnosis of pure red cell aplasia and seven months after thymectomy, bone marrow aspiration and biopsy showed an absence of megakaryocytes, marked erythroid hypoplasia with normal myeloid series. A diagnosis of amegakaryocytic thrombocytopenia and pure red cell aplasia was made. Oral steroid maintenance therapy resulted in recovery of platelet count. She has still transfusion-dependant anemia but platelet and neutrophil counts had been maintained in normal range for more than five months, until the last follow-up. We think that autoreactive T cells may induce a clinical autoimmune response even after eradication of thymoma, and aplastic anemia as a late complication following thymectomy was described in previous cases. This patient also has to be under a close observation because of the possibility to evolve into aplastic anemia.
Aged ; Bone Marrow/pathology ; Female ; Humans ; Imidazoles/therapeutic use ; Megakaryocytes/pathology ; Pregnadienetriols/therapeutic use ; Red-Cell Aplasia, Pure/complications/*diagnosis ; Thrombocytopenia/*diagnosis/drug therapy/*etiology ; Thymectomy/*adverse effects ; Thymoma/*complications/diagnosis/surgery ; Thymus Neoplasms/*complications/diagnosis/surgery

The objective of study was to investigate the in vitro suppressive effect of angelica polysaccharide (APS) on human cytomegalovirus-induced apoptosis via direct infection in CHRF-288-11 cells. HCMV AD169 directly infected CHRF-288-11 were cultured in vitro, APS in different doses were added on day 3 after the infection of virus. Cells of every group were collected at different time points. HCMV DNA of cells were detected by using polymerase chain reaction and the apoptotic cells were examined by using Hoechst staining, MTT assay, DNA fragmentation assay and flow cytometry. The results showed that the APS to some extent inhibited the apoptosis of CHRF cells infected by HCMV in vitro in a dose-dependent manner. The expression of HCMV IEA in CHRF-288-11 cells was found by PCR amplification. Morphology observation, flow cytometry assay and DNA fragmentation assay revealed the existence of apoptosis. With the dose decrease of APS added to the infected CHRF cells, the percentage of apoptotic cells increased. It is concluded that the HCMV AD169 can infect CHRF cells directly in vitro and decrease cell viability. HCMV AD169 infection increases the apoptosis of CHRF cells in time-dependent manner. When APS was added to the CHRF cells infected by HCMV AD169 in vitro, the viability of CHRF cells increase, which indicated that APS to some extent protects the CHRF cells infected by HCMV. APS suppresses the cytomegalovirus-induced apoptosis in CHRF cells directly infected in vitro in dose-dependent manner.
Angelica ; chemistry ; Apoptosis ; drug effects ; Cells, Cultured ; Cytomegalovirus ; Humans ; Megakaryocytes ; cytology ; drug effects ; virology ; Polysaccharides ; pharmacology

OBJECTIVETo investigate the effect of Angelica polysaccharide (APS), platelet-derived growth factor (PDGF) and thrombopoietin (TPO) on the proliferation and apoptosis of human megakaryocytic cell line M-07e.

METHODSCell count and the viability testing of M-07e cells (trypan blue exclusion assay) were performed at 24 hours, 48 hours and 72 hours after treatment with APS, PDGF or TPO. Three apoptosis related flow cytometric assays including Annexin V, Caspase-3 and JC-1 were performed to determine apoptotic rate of each group at 72 hours after the treatment.

RESULTSAfter the incubation, the number of M-07e cells in the APS, PDGF and TPO group increased and the viabilities of the three groups were significantly higher than the control group (P < 0.05). The dead cells in the APS, PDGF and TPO group were (19.41 +/- 7.59)%, (21.38 +/- 7.25)% and (18.77 +/- 8.00)%, respectively by flow cytometry using Annexin V method, which were significantly lower compared to the control group (34.33 +/- 5.46)%. The expression of the activated caspase-3 in the group of APS, PDGF and TPO were (12.27 +/- 5.18)%, (12.39 +/- 6.26)% and (13.75 +/- 8.25)%, the APS and PDGF group decreased significantly compared to the control group (18.92 +/- 6.09)%. The ratio of total cell deaths in the APS, PDGF and TPO group were (23.64 +/- 6.69)%, (28.00 +/- 10.05)% and (27.99 +/- 8.99)%, the ratio in APS group decreased significantly compared to the control group (39.48 +/- 11.86)% by JC-1 method. Differences between APS and PDGF groups and between APS and TPO groups were not statistically significant.

CONCLUSIONAPS, PDGF and TPO have similar effect in stimulating proliferation and inhibiting serum-free-culture induced apoptosis of M-07e cells.

Angelica ; chemistry ; Apoptosis ; drug effects ; Benzimidazoles ; pharmacology ; Carbocyanines ; pharmacology ; Caspase 3 ; metabolism ; Cell Proliferation ; drug effects ; Flow Cytometry ; Fluorescent Dyes ; pharmacology ; Humans ; Megakaryocytes ; drug effects ; physiology ; Organic Chemicals ; pharmacology ; Platelet-Derived Growth Factor ; pharmacology ; Thrombopoiesis ; Thrombopoietin ; pharmacology

OBJECTIVETo explore the clinical effect and possible mechanism of Shengxueling (SXL), a Chinese medical preparation mainly consisting of ginseng saponins, in treating refractory idiopathic thrombocytopenic purpura (ITP).

METHODSThe selected 69 patients with ITP were randomly assigned to two groups, the 37 patients in the treated group were treated orally by SXL with the dose for adult as 60 mg twice a day for two weeks. Then when no marked rise of platelet count after that, the dose would be doubled and administered for another two weeks. Then the dose could be gradually reduced to the initiative level in patients who responded to the treatment, and if they did not, the treatment was regarded as ineffective and be terminated. The 32 patients in the control group were treated with ampeptide elemente instead of SXL, 0.4 g each time three times a day in the first two weeks, and, if that was ineffective, 0.2 g would be added each time and 1.8 g would be administered a day for two more weeks. Four weeks' treatment was regarded as one therapeutic course for both groups and the observation lasted for two successive courses in patients showing positive reslonse.

RESULTSIn the 37 patients in the treated group, markedly effective was obtained in 7 (19.0%), favorably effective in 15 (40.5%), improved in 5 (13.5%) and ineffective in 10 (27.0%), the total effective rate being 59.5%. The corresponding number in the 32 patients in the control group was 4 (12.5%), 6 (18.8%), 3 (9.4%), 19 (59.4%) and 31.3% respectively. Comparison showed the difference in therapeutic efficacy between the two groups was significant (P<0.05).

CONCLUSIONSXL is a safe and effective preparation for treatment of ITP, showing an immediate effect which is obviously superior to that of ampeptide elemente with less adverse effect.

Administration, Oral ; Adolescent ; Adult ; Amino Acids, Essential ; therapeutic use ; Bone Marrow ; pathology ; physiopathology ; Child ; Drug Administration Schedule ; Drugs, Chinese Herbal ; administration & dosage ; adverse effects ; therapeutic use ; Female ; Humans ; Male ; Megakaryocytes ; pathology ; Platelet Count ; Purpura, Thrombocytopenic, Idiopathic ; blood ; physiopathology ; therapy ; Treatment Outcome

To investigate the effect of S-nitrosoglutathione (GSNO), a nitric oxide donor, on platelet production from megakaryocytes differentiated from cord blood CD34(+) cells in vitro, the CD34 (+) cells from eight fresh umbilical cord blood samples by a high-gradient magnetic cell sorting (MACS) system were cultured in serum-free medium for 14 d with thrombopoietin (TPO) 50 ng/ml, IL-3 10 ng/ml, stem cell factor (SCF) 50 ng/ml and rHuGM-CSF 20 ng/ml. Then, CD61 (+) cells were purified by MACS system from these CD34 (+) cells, and were cultured in serum-free medium supplemented with TPO 50 ng/ml, IL-3 10 ng/ml and SCF 50 ng/ml in the presence (treatment group) and absence (control group) of GSNO for 30 min or 2 h. Platelet-sized particles were counted by flow cytometry; megakaryocyte structure was detected by scanning electron microscope. Aggregation of the thrombin-induced platelet particle was observed under inversion microscope. cGMP was assessed by commercial ELISA kit. The results showed that, compared with the control group, the number of platelet-sized particles significantly increased (P<0.05) in the treatment group, in which megakaryocytes presented significant pseudopod formation and extensive membrane blebbing. The platelet particle aggregation could be observed under microscope after thrombin induction. cGMP activity was significantly increased after treatment with GSNO (P<0.05). These results propose that GSNO can facilitate platelet production from megakaryocyte, and it may be partly through cGMP pathway.
Antigens, CD34 ; analysis ; Blood Platelets ; cytology ; Cell Differentiation ; drug effects ; Cyclic GMP ; blood ; Female ; Fetal Blood ; cytology ; Hematopoiesis ; drug effects ; Hematopoietic Stem Cells ; cytology ; Humans ; Megakaryocytes ; cytology ; Nitric Oxide ; physiology ; Platelet Aggregation ; drug effects ; Pregnancy ; S-Nitrosoglutathione ; pharmacology

This study was aimed to investigate the effect of some culture system composed of various cytokine combinations (TPO, SCF, FL, IL-1, IL-3, IL-6) on ex vivo expansion of megakaryocytic progenitors induced from CD34+ cells of peripheral blood and to seek a optimal cytokine combination and culture time. Mononuclear cells were isolated from mobilized peripheral blood (MPB) by density gradient centrifugation over Ficoll. CD34+ cells were purified by using an immunomagnetic bead separation system. The selected CD34+ cells were seeded in Iscove's modified Kulbecco's medium (IMDM) supplemented with fetal calf serum (FCS) and various kinds of cytokines. After 15 days of culture, the content of CD41+ cells in culture system were determined by flow cytometry, and the number of megakaryocyte colony-forming unit (CFU-MK) was measured simultaneously. The results showed that after definited days of culture, the cytokine combination TPO/FL/IL-6/IL-3 was the most suitable for MPB to obtain high number of MK, and better than any other three groups (P < 0.05). The increase multiple of CD41+ cells was 93.97 +/- 17.27 on day 5 and 131.23 +/- 18.26 on day 10. On day 15, the proportion and the increase multiple of CD41+ cells decreased obviously. The expansion multiples of CFU-MK were 93.33 +/- 10.02 on day 5 and 120.67 +/- 13.01 on day 10, higher than any other groups. It is concluded that TPO/FL/IL-6/IL-3 combination was the best optimal for expansion ex vivo of megakaryocytic progenitors from MPB, and its suitable duration of culture was 10 days; a culture system for expansion ex vivo of megakaryocytic progenitors have been established in this study.
Antigens, CD34 ; biosynthesis ; Blood Cells ; cytology ; Blood Platelets ; cytology ; Cell Culture Techniques ; methods ; Cell Differentiation ; drug effects ; Hematopoietic Stem Cell Mobilization ; methods ; Humans ; Interleukin-3 ; pharmacology ; Interleukin-6 ; pharmacology ; Megakaryocytes ; cytology ; Stem Cells ; cytology ; Thrombopoietin ; pharmacology