Effect and Involved Mechanism of RSL3-induced Ferroptosis in Acute Leukemia Cells MOLM13 and Drug-resistant Cell Lines / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect and involved mechanism of RSL3 on ferroptosis action in acute leukemia cells MOLM13 and its drug-resistant cells.@*METHODS@#After MOLM13 treated with RSL3, CCK-8 assay was performed to detect cell viability, flow cytometry was used to detect the reactive oxygen species (ROS) level of the cells, RT-qPCR and Western blot were used to detect the expression of glutathione peroxidase 4 (GPX4). After MOLM13/IDA and MOLM13/Ara-C, the drug-resistant cell lines were constructed, the ferroptosis induced by RSL3 was observed. Bone marrow samples were collected from patients with acute monocytic leukemia. RT-qPCR and Western blot were performed to detect the expression of related genes and proteins involved in ferroptosis pathway.@*RESULTS@#RSL3 significantly inhibited the cell viability of MOLM13 and increased the intracellular ROS level, which were partially reversed by ferrostatin-1. The mRNA and protein expression of GPX4 decreased in MOLM13 treated with RSL3. RSL3 inhibited the viability of MOLM13/IDA and MOLM13/Ara-C cells more strongly than that of non-drug resistant cells, also increased the intracellular ROS level . The cytotoxic effects were partially reversed by ferrostatin-1. The mRNA and protein expressions of GPX4 in MOLM13/IDA and MOLM13/Ara-C cells were higher than those in non-drug resistant cells. The mRNA and protein levels of GPX4 in bone marrow of relapsed/refractory acute mononuclear leukemia patients were higher than those of ordinary acute mononuclear leukemia patients.@*CONCLUSION@#RSL3 can induce non-drug resistant cells MOLM13 ferroptosis by inhibiting GPX4 activity. MOLM13/IDA and MOLM13/Ara-C are more sensitive to RSL3 compared with non-drug resistant cells MOLM13, which may be caused by the differences in GPX4 expression. The expressions of GPX4 mRNA and protein in relapsed/refractory acute mononuclear leukemia are higher than those in ordinary acute mononuclear leukemia.

Analysis of lumbosacral sagittal balance parameter variation in minimally invasive transforaminal lumbar interbody fusion with real-time 3D navigation techniques / 中国骨伤

OBJECTIVE@#To explore the dynamic changes of lumbosacral sagittal parameters after real-time three-dimensional navigation assisted minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and traditional open TLIF for treatment of lumbar degenerative disease.@*METHODS@#The clinical data of 61 patients with lumbar degenerative disease underwent single-segment surgery from September 2017 to September 2019 were retrospectively analyzed. Among them, 31 cases underwent MIS-TLIF with 3D navigation techniques (MIS-TLIF group) and another 30 cases underwent conventional open TLIF (traditional open TLIF group). The basic information, operative time and intraoperative blood loss were collected. The sagittal radiologic parameters were measured before surgery and 3 months after surgery, including lumbar lordosis (LL), segmental lordosis (SL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), anterior disc height (ADH), posterior disc height(PDH).And the average disc height(DH) and pelvic incidence to lumbar lordosis mismatch (PI-LL) were calculated.@*RESULTS@#Operative time and intraoperative blood loss in MIS-TLIF group were significantly less than in traditional open TLIF group(@*CONCLUSION@#Real-time navigation-assisted MIS-TLIF and traditional open TLIF can recover DH in a short term for lumbar degenerative diseases, improve LL and PI-LL, and make the arrangement of the sagittal plane of the lumbosacral region more coordinated after surgery. But only the navigation assisted MIS -TLIF can significantly improve SL. Compared with traditional open TLIF, real-time navigation assisted MIS-TLIF in the treatment of degenerative lumbar diseases has the advantages of short operation time and less intraoperative bleeding.

Expression and Significance of HIF-1α in Erythropoiesis of Secondary Iron Overload Disease after Irradiation Damage / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To study the expression of hypoxia inducible factor 1α(HIF-1α) of iron-overloaded in irradiated mice and its effect on erythropoiesis.</p><p><b>METHODS</b>Twenty mice were randomly divided into 4 groups: Ctrl (control group), IR (irradiation group), IO (irradiation + iron overload group), and RAPA (rapamycin treatment group). The iron overload model was verified. The CFU-E (colony forming unit-erythroid) and BFU-E(burst colony forming unit-erythroid) were cultured; flow cytometry was used to detect the ratios of early stage (Ter119CD71) to late stage (Ter119CD71) of primitive erythroblasts; RT-PCR was used to detect the mRNA expression of HIF-1α and its related signal molecules in bone marrow cells.</p><p><b>RESULTS</b>The expression of HIF-1α in IR and IO group was significantly higher than that in Ctrl group, and that in IO group was significantly higher than IR group (P<0.05). The ratio of late stage primitive erythroblasts, the number of CFU-E and BFU-E in both IR and IO group were lower than those in Ctrl group, and those in IO group were significantly lower than those in IR group (P<0.05). Compared with Ctrl group, the expression of HIF-1α related signal pathway molecules in both IR and IO group was significantly decreased (P<0.05). Compared with IO group, the expression of HIF-1α and its related signal molecules in RAPA(mTOR inhibitor) group was decreased significantly (P<0.05), the number of BFU-E was increased significantly(P<0.05).</p><p><b>CONCLUSION</b>Irradiation induces the increase of HIF-1α and the decrease of the ability of hematopoietic colony formation and the ratio of late stage primitive erythroblasts. Iron overload can aggravate the injury. mTOR inhibitor rapamycin can partially alleviate the injury, suggesting that iron overload can lead to injury of erythropoiesis through HIF-1α.</p>

Effects of Iron Overload on the Apoptosis and Function of Splenic CD8+ T Cells in Mice / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effects of iron overload on apoptosis and function of splenic CD8+ T cells in mice.</p><p><b>METHODS</b>Forty C57BL/6 mice were randomly divided into control groups, Iron overload (IO), IO+NAC and IO+DFX groups. The iron overload model was established by intraperitoneal injection of iron dextran, and saline was injected as the control. The levels of intracellular reactive oxygen species (ROS) and labile iron pool (LIP) were analyzed by measuring the mean fluorescence intensity (MFI) of 2-7 dichlorofluorescein (DCF) or calcein. The ratio of CD8+ T cells and the levels of IFN-γ, TNF-α, Granzyme-B, and perforin in CD8+ T cells were detected by flow cytometry. The CD8+ T cell apoptosis was determined by flow cytometry with Annexin V/PI double staining. Real-time PCR was used to detect the expression of IFN-γ, TNF-α, Granzyme-B, perforin, BCL-2, and bax at mRNA level in CD8+ T cells.</p><p><b>RESULTS</b>Iron overload was found by spleen iron staining and flow cytometry. The level of intracellular ROS in iron overload (IO) groups was higher than that of the control groups (P<0.01). The percentage of CD8+ T cells in spleen from mice with IO was lower than that in control groups (P<0.05). The expression of IFN-γ and Granzyme-B in CD8+ T cells in IO group were lower than that in control group, the expression of IFN-γ and Granzyme-B at mRNA level in CD8+ T cells was lower than that of control group (P<0.05). CD8+ T cell apoptosis in iron overload group was significantly higher than that in control groups (P<0.01); the expression of BCL-2 at mRNA level was lower than that in control group, but the expression of BAX at mRNA level was higher than that in control group (P<0.05). These effects could be reversed after treating iron-overloaded mice with DFX or NAC.</p><p><b>CONCLUSION</b>Iron overload can inhibit the ratio of CD8+ T cells of splenic cells in mice, decrease the expression of IFN-γ, Granzyme-B, increase the apoptosis of CD3+ CD8+/CD8-. These effects may be regulated through increasing the intracellular ROS level, and can be partially reversed after treating iron-overloaded mice with DFX or NAC.</p>