Genetic inhibition of MLKL exerts protective effects against cognitive impairment and neuroinflammation in a cerebral small vessel disease model / 中国药理学与毒理学杂志

OBJECTIVE To identify the role of mixed lineage kinase domain like protein(MLKL)in cerebral small vessel disease(CSVD)and explore the underlying mechanism.METHODS Transient bilateral common carotid artery occlusion(tBCCAO)was used to establish a mouse model of CSVD.Immunofluorescence staining and Western blotting were used to observe the expres-sions of RIPK3/MLKL signaling molecules in brain tissues at 7,14 and 28 d after tBCCAO.Open field test,rotarod test,Y-maze and novel object recognition test were used to observe the effect of MLKL knockout on cognitive func-tion after tBCCAO.Blood-brain barrier(BBB)disruption was observed by sodium fluorescein permeability test and the expressions of tight junction proteins.Immunoflu-orescence staining and Western blotting were used to detect the expression of microglia marker Iba-1,astro-cyte marker GFAP,and NLRP3/Caspase-1 signaling mol-ecules in the hippocampus of CSVD mice.ELISA was used to detect the level of inflammatory factors(TNF-α,IL-1β,IL-18)in hippocampus.RESULTS The expres-sions of RIPK3/MLKL signaling molecules increased in cortex and hippocampus after tBCCAO,especially on day 14.The expression of pMLKL mainly increased in neurons,glia cells and endothelial cells in CSVD mice.MLKL knockout improved the cognitive functions such as motor learning,spatial learning and working memory,and object recognition ability in CSVD mice.MLKL knock-out alleviated the leakage of sodium fluorescein and attenuated the down-regulation of tight junction proteins at 1 d and 14 d after tBCCAO.At 14 d after tBCCAO,MLKL knock out inhibited the activations of microglia and astrocytes,attenuated the expressions of NLRP3/cas-pase-1 molecules,and decreased the levels of inflamma-tory factors in the hippocampus of mice.CONCLUSION Genetic inhibition of MLKL exerts protective effects against cognitive impairment by ameliorating BBB dam-age and neuroinflammation in a mouse cerebral small vessel disease model.

Development and application of a highly sensitive method for detection of mutation of FMS-like tyrosine kinase-3-tyrosine kinase domain of acute myeloid leukemia / 中国生物制品学杂志

@#ObjectiveTo develop a highly sensitive method for detection of mutation of FMS-like tyrosine kinase-3-tyrosine kinase domain(FLT3-TKD)of acute myeloid leukemia(AML)and apply to the monitor of minimal residual disease(MRD).MethodsRecombinant plasmids containing wild FLT3 and mutant FLT3-D835Y were constructed respectively and mixed at certain ratios.The obtained standard plasmids with mutation rates of 50%,1%,0.1% and 0% respectively were determined by restriction fragment length polymorphism(RFLP)in combination with Sanger method.The plasmid DNA standards and blood DNA standards,at various FLT3-D835Y mutation rates,were determined by the developed method to verify the sensitivity.The genomic DNA samples of patients with AML before and after treatment were determined by the developed method to monitor the MRD.ResultsSequencing proved that both the recombinant plasmids containing wild FLT3 and mutant FLT3-D835Y were constructed correctly.The sensitivity of developed method increased to 0.1% through Sanger method combined with digestion with EcoR Ⅴ/Xho Ⅰ and recovery of mutant fragments in determination of purified plasmid DNA and collected blood DNA samples.MRD was detected in the peripheral blood sample of a patients with AML in complete remission period by the developed method but not by Sanger method.ConclusionA highly sensitive method for detection of FLT3-TKD mutation was developed,which was of an important clinical significance in guiding the treatment of AML and monitoring the MRD in complete remission period.

Progress in study on the final executor of necroptosis MLKL and its inhibitors / 中南大学学报(医学版)

Necroptosis is one of the regulated cell death, which involves receptor interacting protein kinase (RIPK) 1/RIPK3/mixed lineage kinase domain like protein (MLKL) signaling pathway. Among them, MLKL is the final execution of necroptosis. The formation of RIPK1/RIPK3/MLKL necrosome induces the phosphorylated MLKL, and the activated MLKL penetrates into the membrane bilayer to form membrane pores, which damages the integrity of the membrane and leads to cell death. In addition to participating in necroptosis, MLKL is also closely related to other cell death, such as NETosis, pyroptosis, and autophagy. Therefore, MLKL is involved in the pathological processes of various diseases related to abnormal cell death pathways (such as cardiovascular diseases, neurodegenerative diseases and cancer), and may be a therapeutic target of multiple diseases. Understanding the role of MLKL in different cell death can lay a foundation for seeking various MLKL-related disease targets, and also guide the development and application of MLKL inhibitors.

IKKβ mediates homeostatic function in inflammation via competitively phosphorylating AMPK and IκBα

Inhibitor of nuclear factor kappa-B kinase subunit beta (IKKβ) is one of important kinases in inflammation to phosphorylate inhibitor of nuclear factor kappa-B (IκBα) and then activate nuclear factor kappa-B (NF-κB). Inhibition of IKKβ has been a therapeutic strategy for inflammatory and autoimmune diseases. Here we report that IKKβ is constitutively activated in healthy donors and healthy Ikkβ C46A (cysteine 46 mutated to alanine) knock-in mice although they possess intensive IKKβ-IκBα-NF-κB signaling activation. These indicate that IKKβ activation probably plays homeostatic role instead of causing inflammation. Compared to Ikkβ WT littermates, lipopolysaccharides (LPS) could induce high mortality rate in Ikkβ C46A mice which is correlated to breaking the homeostasis by intensively activating p-IκBα-NF-κB signaling and inhibiting phosphorylation of 5' adenosine monophosphate-activated protein kinase (p-AMPK) expression. We then demonstrated that IKKβ kinase domain (KD) phosphorylates AMPKα1 via interacting with residues Thr183, Ser184, and Thr388, while IKKβ helix-loop-helix motifs is essential to phosphorylate IκBα according to the previous reports. Kinase assay further demonstrated that IKKβ simultaneously catalyzes phosphorylation of AMPK and IκBα to mediate homeostasis. Accordingly, activation of AMPK rather than inhibition of IKKβ could substantially rescue LPS-induced mortality in Ikkβ C46A mice by rebuilding the homeostasis. We conclude that IKKβ activates AMPK to restrict inflammation and IKKβ mediates homeostatic function in inflammation via competitively phosphorylating AMPK and IκBα.

Programmed Necrosis Inducers for Cancer Treatment / 中国医学科学院学报

Programmed necrosis,a mode of cell death independent of Caspase,is mainly mediated by receptor-interacting protein kinase-1 (RIPK1),receptor-interacting protein kinase-3 (RIPK3),and mixed lineage kinase domain-like protein (MLKL).Studies have demonstrated that programmed necrosis has the dual role of promoting and inhibiting tumor growth and thus we can control the development of tumor by regulating programmed necrosis.The drugs capable of inducing programmed necrosis show potential anti-tumor activity.In addition,inducing programmed necrosis is an effective way to overcome tumor resistance to apoptosis.This paper summarized the mechanisms of programmed necrosis and its relationship with tumors.We focused on the antitumor activity of programmed necrosis inducers including natural products,chemotherapeutic drugs,death receptor ligands,kinase inhibitors,inorganic salts,metal complexes,and metal nanoparticles.These agents will provide new therapeutic candidates for the treatment of tumors,especially the tumors acquiring resistance to apoptosis.

Effect of effective parts of Dracocephalum moldavica on the necroptosis of HBMECs after OGD/R injury / 药学学报

We investigated the ability of Dracocephalum moldavica (EPDM) flavonoids to protect human brain microvascular endothelial cells (HBMECs) from necroptosis induced by ischemia-reperfusion injury. To mimic the process of cerebral ischemia-reperfusion injury, a necroptosis model was established by treatment with the pan-cysteine aspartic acid protease (caspase) inhibitor Z-VAD-FMK combined with oxygen-glucose deprivation/re-oxygenation (OGD/R) injury using HBMECs. Cell proliferation and cytotoxicity (cell counting kit-8, CCK-8) was used to measure cell viability. A Hoechst33342/PI fluorescent double-staining method was exploited to determine the rate of cell necroptosis. A commercial kit was used to detect lactate dehydrogenase in the cell culture supernate. DCFH-DA probes, calcein AM and JC-1 probes were used to measure changes in ROS production, mitochondrial membrane permeability transformation pore (MPTP) opening and mitochondrial membrane potential (MMP), respectively. Enzyme-linked immunosorbent assay (ELISA) kits were chosen to detect the release of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). Western blotting was used to detect necroptosis-related proteins. The results show that relative to control group, Z-VAD-FMK combined with OGD/R injury reduced cell viability, increased the necroptosis rate and the levels of LDH and ROS in HBMECs. The MPTP of the model group cells opened and the MMP reduced. TNF-α, IL-1β, and IL-6 levels were significantly elevated. Furthermore, the expression of receptor-interacting protein kinase 3 (RIP3) and mitochondrial phosphoglycerate mutase 5 (PGAM5) was significantly increased, accompanied by an increase of phosphorylated mixed-lineage kinase domain-like protein (p-MLKL)/MLKL. EPDM partially reversed the changes of the above-mentioned factors in HBMECs induced by Z-VAD-FMK plus OGD/R injury. These results indicate that EPDM may protect HBMECs from cerebral ischemia-reperfusion injury by inhibiting the RIP3/MLKL/PGAM5 pathway and MPTP opening to maintain mitochondrial function, thereby providing a scientific basis for the use of EPDM in the treatment of cerebral ischemia-related diseases.

Necroptosis in inflammatory bowel disease: A potential effective target / 中南大学学报(医学版)

The morbidity of inflammatory bowel diseases (IBD) is rising rapidly but no curative therapies to prevent its recurrence. Cell death is crucial to maintaining homeostasis. Necroptosis is a newly identified programmed cell death and its roles played in IBD need to be explored. Necroptosis is mediated by receptor interacting protein kinase 1 (RIPK1), RIPK3, and mixed lineage kinase domain-like protein (MLKL), which resulted in cell swelling, plasma membrane rupture, intracellular content leaking, and eventually cell death as well as the promotion of inflammation. Studies have found that inhibiting necroptosis alleviated IBD in animal models and IBD patients with an increased level of necroptosis in inflammatory tissues, indicating that necroptosis is related to the pathogenesis of IBD. However, due to the complexity in regulation of necroptosis and the involvement of multiple functions of relevant signaling molecules, the specific mechanism remains elusive. Necroptosis may play a vital regulatory role in the pathogenesis of IBD, which provides a new idea and method for further exploring the therapeutic target of IBD.

Effect of Danggui Buxuetang on Podocyte Injury in Diabetic Kidney Disease Rats： An Exploration Based on RIPK1/RIPK3/MLKL Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effect of Danggui Buxuetang on the podocyte injury and receptor-interacting protein kinase 1/receptor-interacting protein kinase3/mixed lineage kinase domain-like protein （RIPK1/RIPK3/MLKL） signaling pathway in diabetic kidney disease （DKD） ratsand to explore its possible mechanism against DKD. MethodEight of the 50 SD rats were randomly classified intoa normal group， and the remaining were fed a high-glucose and high-fat diet for six weeks and then intraperitoneally injected with 0.035 g·kg-1streptozotocin （STZ） for inducing type 2 diabetes. After successful modeling，they were randomized into the model group，high- and low-dose （1.44，0.72 g·kg-1） Danggui Buxuetang groups， and irbesartan （0.017 g·kg-1）group. After 20 weeks of drug intervention， the fasting blood glucose （FBG）， kidney index （KI），and urinary microalbumin-to-urine creatinine ratio （UACR）were detected in each group. The pathological changes in renal tissue were observed by hematoxylin-eosin （HE） staining， followed by the observation of ultrastructural changes in podocytes under the transmission electron microscope. The levels of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） in renal tissue of rats were determined by enzyme-linked immunosorbent assay （ELISA）， and the protein expression levels of RIPK1， RIPK3， and MLKL in rat kidney tissue by immunohistochemistry. The apoptosis rate of podocytes was detected by in situ nick end-labeling （TUNEL） assay. The mRNA expression levels of RIPK1， RIPK3， and MLKL in kidney tissue of rats were measured by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）， and the protein expression levels of RIPK， RIPK3， and MLKL and podocyte marker Wilms tumor protein-1 （WT-1） in rat kidney tissue were assayed by Western blot. ResultCompared with the normal group， the model group exhibited elevated FBG， UACR， and KI （P<0.01）， glomerular hypertrophy， thickened basement membrane， increased extracellular matrix， mesangial hyperplasia， foot process fusion or loss， enhanced apoptosis in renal tissue， up-regulated TNF-α and IL-6 levels （P<0.01） and RIPK1/RIPK3/MLKL mRNA and protein expression （P<0.01）， and down-regulated WT-1 protein expression. Compared with the model group， Danggui Buxuetang high-dose group significantly reduced the levels of FBG， UACR， and KI， improved renal histopathology， podocyte loss， and apoptosis in renal tissue， down-regulated TNF-α and IL-6 levels and RIPK1/RIPK3/MLKL mRNA and protein expression （P<0.05， P<0.01）， and up-regulated WT-1 protein expression. ConclusionDanggui Buxuetang alleviates podocyte injury and delays the development of DKD possibly by regulating the RIPK1/RIPK3/MLKL signaling pathway.

Effect of programmed necrosis inhibitor Nec-1 on lead-induced BV2 cell injury / 环境与职业医学

Background Programmed necrosis is closely related to the occurrence and development of neurodegenerative diseases, but whether lead causes programmed cell necrosis has not been reported. Objective This experiment is designed to probe into the function of programmed necrosis and the effect of its inhibitor on lead-induced microglia (BV2 cell) injury. Methods The BV2 cells at logarithmic growth phase were treated with 0, 1, 5, 10, 25, 50, 100, and 200 μmol·L−1 lead acetate for 12, 24, 36, and 48 h, respectively, and methylthiazolyldiphenyl-tetrazolium bromide (MTT) was used to determine cell viability. After treatment with 0, 25, 50, and 100 μmol·L−1 lead acetate for 24 h, enzyme-linked immunosorbent assay, Western blotting, and flow cytometry were used to determine the expressions of tumor necrosis factor-α (TNF-α), receptor-interacting protein kinase 3 (RIPK3), receptor-interacting protein kinase 1 (RIPK1), and mixed lineage kinase domain-like protein (MLKL) in the cells, and the effect of RIPK1 inhibitor Nec-1 pretreatment on lead-induced BV2 cell injury . Results The BV2 cell viability decreased with higher lead concentration (r12 h=−0.995, r24 h=−0.984, r36 h=−0.983, r48 h=−0.981, all P<0.01) and time extension (only for 5 μmol·L−1 lead acetate, r=−0.994, P<0.01). Compared with the control group, the BV2 cell viability decreased at the same exposure time when the concentration of lead was above 10 μmol·L−1 (P<0.01). Compared with the control group, the expressions of RIPK1 and MLKL were increased in the 25, 50, and 100 μmol·L−1 lead groups (P<0.05 or 0.01), accompanied by an increase in the contents of inflammatory cytokine TNF-α, especially in the 100 μmol·L−1 lead group, the increment was the highest (P<0.01). The expression levels of p-RIPK1 and p-MLKL in BV2 cells were both increased when the concentration of lead acetate was above 50 μmol·L−1 (P<0.01). In addition, pretreatment with Nec-1 increased the cell viability rate and decreased the necrosis and late apoptosis rate of BV2 cells exposed to lead compared with corresponding lead exposure groups (P<0.05). Conclusions Lead can reduce BV2 cell viability, increase necrosis rate, and up-regulate the expressions of RIPK1, RIPK3, amd MLKL, and the phosphorylation levels of RIPK1 and MLKL. The RIPK1 inhibitor Nec-1 has an intervention effect on lead-induced damage in BV2 cells, indicating that programmed necrosis may play a role in lead neurotoxicity.

Complex roles of necroptosis in cancer / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Necroptosis is a tightly regulated form of necrosis that requires the activation of receptor-interacting protein (RIP) kinases RIPK1 and RIPK3, as well as the RIPK3 substrate mixed lineage kinase domain-like protein (MLKL). Because of membrane rupture, necroptotic cells release damage-associated molecular patterns (DAMPs) that evoke immune responses. Necroptosis is emerging as an important cellular response in the modulation of cancer initiation, progression, and metastasis. Necroptosis of cancer cells is considered to be an immunogenic cell death capable of activating anti-tumor immunity. Necroptosis also participates in the promotion of myeloid cell-induced adaptive immune suppression and thus contributes to oncogenesis. In addition, necroptosis of endothelial cells and tumor cells is conducive to tumor metastasis. In this review, we summarize the current knowledge of the complex role of necroptosis in cancer and discuss the potential of targeting necroptosis components for cancer therapies.

Effect of interferon-γ combined with tumor necrosis factor-related apoptosis-inducing ligand on programmed necrosis of HaCaT cells and its mechanisms / 中华皮肤科杂志

Objective To evaluate the inductive effect of interferon-γ(IFN-γ) combined with tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) on programmed necrosis of the human immortalized keratinocyte cell line HaCaT,and to explore its mechanisms.Methods In vitro cultured HaCaT cells were divided into several groups:negative control group receiving no treatment,IFN-γ group treated with 50 μg/L IFN-γ,TRAIL group treated with 4 μg/L TRAIL,and cytokine combination group treated with 50 μg/L IFN-γ and 4 μg/L TRAIL or zVAD combination group pretreated with 40 μmo/L zVAD for 1 hour followed by the treatment with 50 μg/L IFN-γand 4 μg/L TRAIL.After 48-hour treatment,the morphology of HaCaT cells were observed under a light microscope,methyl-thiazolyl-tetrazolium assay was performed to evaluate the inhibitory effect of the treatment on the proliferation of HaCaT cells,and double staining flow cytometry to detect the necrosis of HaCaT cells.Meanwhile,real-time fluorescence-based quantitative PCR (qPCR) was conducted to determine the mRNA expression of receptor interaction protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL),Western blot analysis to determine the expression of RIP1,RIP3,MLKL proteins and their phosphorylated forms (pRIP1,pRIP3,pMLKL),immunofluorescent staining to observe the distribution of pRIP3 and pMLKL in HaCaT cells,and the level of reactive oxygen species (ROS) in HaCaT cells in the above groups was detected by the fluorescence probe DCFH-DA.Statistical analysis was carried out with SPSS 22 software by using one-way analysis of variance (ANOVA) for comparing indices among different groups,and least significant difference (LSD)-t test for multiple comparisons.Results After 48-hour treatment,HaCaT cells in the cytokine combination group and zVAD combination group showed necrosis-like morphologic features.Methyl-thiazolyl-tetrazoliumassay revealed significant differences in the survival rate of HaCaT cells among the IFN-γgroup,TRAIL group,cytokine combination group,zVAD combination group and negative control group (73.16％ ± 5.71％,81.46％ ± 4.68％,72.18％ ± 2.93％,69.67％ ± 3.24％ and 100％,respectively;F =24.34,P ＜ 0.001).The necrosis rate of HaCaT cells was notably higher in the cytokine combination group and zVAD combination group (9.86％ ± 1.31％,10.33％ ± 2.16％,respectively) than in the negative control group (5.26％ ± 0.91％,t =4.61,5.07,respectively,both P ＜ 0.05).qPCR revealed that the mRNA expression of RIP3 and MLKL significantly increased in the cytokine combination group and zVAD combination group compared with the negative control group (tRIP3 =0.99,1.84,tMLKL =1.51,2.17,respectively,all P ＜ 0.05).Western blot analysis suggested that the protein expression of RIP1,RIP3,MLKL,pRIP1,pRIP3 and pMLKL significantly increased in the cytokine combination group compared with the negative control group (all P ＜ 0.05),and the zVAD combination group showed significantly decreased caspase 8 expression and increased expression of the above proteins compared with the cytokine combination group.Fluorescence microscopy showed that enhanced green dot-like or clump-like fluorescent spots (representing pRIP3) could be observed in the cytoplasm,and red fluorescent spots (representing pMLKL) could be seen on the cell membrane in the cytokine combination group.The average fluorescence intensity of ROS was significantly higher in the cytokine combination group than in the negative control group (t =702.00,P ＜ 0.05).Conclusion IFN-γcombined with TRAIL can induce the programmed necrosis of HaCaT cells with increased level of ROS.

Complex roles of necroptosis in cancer / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Necroptosis is a tightly regulated form of necrosis that requires the activation of receptor-interacting protein (RIP) kinases RIPK1 and RIPK3, as well as the RIPK3 substrate mixed lineage kinase domain-like protein (MLKL). Because of membrane rupture, necroptotic cells release damage-associated molecular patterns (DAMPs) that evoke immune responses. Necroptosis is emerging as an important cellular response in the modulation of cancer initiation, progression, and metastasis. Necroptosis of cancer cells is considered to be an immunogenic cell death capable of activating anti-tumor immunity. Necroptosis also participates in the promotion of myeloid cell-induced adaptive immune suppression and thus contributes to oncogenesis. In addition, necroptosis of endothelial cells and tumor cells is conducive to tumor metastasis. In this review, we summarize the current knowledge of the complex role of necroptosis in cancer and discuss the potential of targeting necroptosis components for cancer therapies.

Kinase activity of novel receptor interacting protein kinase 3 mutants / 上海交通大学学报（医学版）

Objective:To explore the kinase activity of novel receptor interacting protein kinase 3 (RIPK3) mutants. Methods:The four amino acids (Q84WDF87) of RIPK3 were mutated respectively and these mutants were co-transfected with mixed lineage kinase domain like pseudokinase (MLKL) into HEK293T cells. The auto-phosphorylation of these mutants at S232 and phosphorylation of MLKL at S345 were detected by Western blotting. The interaction between RIPK3 and MLKL was tested by co-immunoprecipitation. The oligomerization of MLKL was detected by non-reducing gel. Results:The kinase activities of RIPK3ΔQ84, RIPK3ΔW85 and RIPK3ΔD86 were effectively decreased. Nevertheless, the kinase activities of RIPK3Q84A/RIPK3Q84E, RIPK3W85Y and RIPK3D86A/RIPK3D86Y did not change markedly. The auto-phosphorylation of RIPK3W85A at S232 was decreased without affecting phosphorylation and oligomerization of MLKL. Conclusion:The amino acid site Q84, W85 or D86 plays a critical role in RIPK3 kinase activity. The kinase activity of RIPK3W85A is decreased, but it does not affect MLKL.

Expression and regulation of mixed lineage kinase domain-like protein in uterus during early pregnancy and decidua in mice / 第二军医大学学报

Objective To investigate the expression of mixed lineage kinase domain-like protein (MLKL) in uterus during early pregnancy and decidua in mice. Methods Different mouse models including early pregnancy model, artificially induced decidualization model and hormone and/or progesterone treatment of uterine model were constructed; human endometrial stromal cells were cultured in vitro and were induced for decidualization by treating with estradiol-17β, medroxyprogesterone acetate and dibutyryl cyclic adenosine monophosphate. The expression of MLKL mRNA and protein in the uterus of early pregnancy, decidual uterus, and hormone-treated uterus in mice were analyzed by real-time fluorescent quantitative PCR, in situ hybridization and Western blotting. The expression of MLKL mRNA in human decidual cells induced in vitro was detected by real-time fluorescent quantitative PCR. Results (1) In the uterus during early pregnancy in mice, the expression of MLKL mRNA and protein in uterine epithelium on the 1st to 4th day of pregnancy (day 1 was day of vaginal sperm) was low and irregular. It was expressed in the uterine epithelium and surrounding decidual cells on the 5th day of pregnacy, and was mainly expressed in the decidua from the 6th to 8th day of pregnancy. After the implantation, the expression of MLKL mRNA and protein was day-by-day increased and reached the highest on the 7th day of pregnancy, with a slight decrease on the 8th day. (2) In the uterus of mice with artificially induced decidualization, MLKL mRNA was expressed in the entire decidual region with high level; while there was no significant expression in the uterus of the control mice. The expression of MLKL protein was consistent with the expression of MLKL mRNA. The expression of MLKL mRNA in human decidual cells induced in vitro was significantly higher than that in the control group (P0.05). (3) The expression of MLKL mRNA and protein in progesterone-treated uterus was significantly increased compared with the control group (P0.05). Conclusion MLKL regulated by steroid hormone progesterone is involved in embryo implantation and decidualization of mammals.

Effects of necroptosis related proteins on brain ischemia/reperfusion injury in mice / 中华行为医学与脑科学杂志

Objective To explore the effect and mechanism of necroptosis related proteins in middle cerebral artery occlusion (MCAO) induced brain ischemia/reperfusion injury in mice.Methods C57BL/6 mice were used to establish the brain ischemia/reperfusion injury model induced by MCAO.MCAO mice were treated with z-VAD.fmk (zVAD,1.1 g/kg),GSK'872 (0.7 g/kg) and combined intervention of zVAD and GSK'872,and neurological defect was evaluated by mNSS while brain infarct volume was measured by TTC staining.Western blot and immunofluorescence assay were used to detect protein expression and location of RIP1,RIP3 and MLKL,respectively.Results Neurological defect and brain infarction were caused by MCAO.Compared with MCAO group,zVAD,GSK'872 and the combined intervention alleviated neurological defect and reduced brain infarct volume significantly (P＜0.05 or P＜0.01).The protein levels of RIP3 and RIP1 MLKL were increased in mice of MCAO group,while GSK'872 and the combined intervention obviously downregulated the aforementioned protein expression [RIP1 (GSK'872:0.64± 0.02 vs MCAO:1.28±0.02,P＜0.01);RIP3 (GSK'872:1.08±0.02 vs MCAO:1.45±0.02,P＜0.01);MLKL (GSK'872:0.54±0.01 vs MCAO:1.00±0.01,P＜0.01)].However,zVAD only slightly reduced protein expression of MLKL (P＜0.05) but didn't change the protein expression of RIP1 and RIP3 (P＞0.05).Conclusion RIP1,RIP3 and MLKL are involved in the execution of necroptosis and contribute to the pathological progress of brain ischemia/reperfusion injury.

Dual transcripts of BCR-ABL & different polymorphisms in chronic myeloid leukaemia patients.

Background & objectives: Chronic myeloid leukaemia is (CML) characterized by the presence of a hallmark chromosomal translocation, the Philadelphia chromosome. Although there are many reports available regarding the different variants of BCR-ABL in CML, we studied the co-expression of e13a2 and e14a2 transcripts and a few polymorphisms in CML patients. Methods: Molecular genetics approach was adapted to screen for polymorphisms, mutation and translocation in BCR, ABL kinase domain and BCR-ABL breakpoint region in 73 CML patients. Results: All eight patients with dual transcripts were found to harbour an exonic polymorphism (c.2700 T>C) and an intronic polymorphism (g.109366A>G) that were earlier reported to be associated with co-expression of both the transcripts. We also observed c.763G>A mutation in ABL kinase domain and two polymorphisms, c.2387 A>G and c.2736A>G in the BCR gene. Interpretation & conclusions: Though our data support the previous findings that co-expression of BCR-ABL transcripts is due to the occurrence of exonic and intronic polymorphisms in the BCR gene, it also shows that the intronic polymorphism can arise without the linked exonic polymorphism. The occurrence of ABL kinase domain mutation is less frequent in Indian population.

Association study of schizophrenia and ankyrin repeat and kinase domain containing 1 gene polymorphism / 中华行为医学与脑科学杂志

Objective To detect the genetic association between schizophrenia and polymorphism of Ankyrin repeat and kinase domain containing 1 ( ANKK1 ) gene. Methods Observed in a sample of 112 parent/offspring trios where the proband net the American Classification and diagnostic Criteria for Mental Disorders The Forth Revised Edition, criteria for schizophrenia using correlation analysis and haplotype relative risk analysis. The polymorphism of Ankyrin repeat and kinase domain containing 1 gene was detected with PCR methods and SNP typing in all nucleus families. Results The rs2734849 allele was connected with schizophrenia(P= 0. 026). Allele T was protective factor( Z= -2.19) and allele A was the hazard factor( Z=2. 19). The rs4938015,rs7118900 and rs1800497 allele were independence with schizophrenia. Three kinds haplotypes of G/A in the rs7118900 -rs2734849, A/C in the rs2734849 -rs1800497, G/A/C in the rs7118900 -rs2734849 -rs1800497 were associated with schizophrenia ( The P values were 0.032,0. 041,0.046, the genotype frequencies were 0. 36,0.29,0. 17 ).Conclusion It shows an association between schizophrenia and the polymorphism at nucleotide of ankyrin repeat and kinase domain containing 1 gene in Chinese.

Low Frequency and Variability of FLT3 Mutations in Korean Patients with Acute Myeloid Leukemia

FLT3 mutations are common genetic changes, and are reported to have prognostic significance in acute myeloid leukemia (AML). The FLT3 internal tandem duplication (ITD) and the D835 activating mutation in the tyrosine kinase domain (TKD) were analyzed by polymerase chain reaction (PCR) in the genomic DNA of Korean patients with AML at diagnosis and during follow-up. There were 226 patients with AML enrolled between March 1996 and August 2005. The incidence of ITD and TKD at diagnosis was 13% (29/226) and 3% (6/226). When compared to Western and other Asian patients with AML, Korean patients had a lower frequency by about two-thirds of ITD and TKD. Among the non-M3 cases (N=203), the patients with an ITD had a significantly shorter event-free survival when compared with those without an ITD (p=0.0079). Among 54 relapsed patients, 9 patients had the FLT3 ITD at diagnosis. Six patients demonstrated a reappearance of the ITD and 3 patients remained negative at relapse. One patient, among 45 patients who relapsed, had a negative baseline ITD but acquired a de novo ITD at relapse. There were 101 samples from 93 patients in remission; they were all negative for an ITD. Among 34 patients who failed to achieve a remission, five patients had a persistent ITD and one patient had a de novo ITD. These results support the concept of resistance of FLT3 ITD leukemic clones to chemotherapy. Therefore, effective therapy with FLT3 targeting agents may improve the prognosis of non-M3 AML patients with the FLT3 mutation.