[摘 要] 目的：探讨lncRNA DLEU2通过EZH2/H3K27me3途径调控IKKα介导甲状腺癌（TC）放射性碘抵抗的作用机制。方法：利用TCGA数据库分析TC中DLEU2的表达及其与EZH2的相关性。构建放射性碘抵抗的TPC-1细胞（RR-TPC-1细胞）模型及裸鼠移植瘤模型，通过敲低或过表达DLEU2（si-DLEU2/OE-DLEU2）、抑制EZH2（UNC1999）、过表达IKKα（OE-IKKα）进行干预，采用qPCR、WB、RIP、ChIP、CCK-8、流式细胞术、TUNEL染色及体内成瘤实验检测基因与蛋白表达、表观修饰、细胞增殖、凋亡及肿瘤生长。结果：TCGA分析显示，DLEU2在TC组织中显著上调（P < 0.001），与患者不良预后相关（P = 0.008 4），且与EZH2表达呈正相关（r = 0.390, P < 0.001）；RIP证实EZH2与DLEU2存在相互作用/结合（P < 0.05）。体外实验表明，敲低DLEU2可显著下调RR-TPC-1细胞中EZH2、IKKα表达及H3K27me3修饰水平，抑制NF-κB通路活化（P < 0.05或P < 0.01），抑制细胞增殖、促进凋亡（均P < 0.05）。联合敲低DLEU2与抑制EZH2进一步增强上述效应，而过表达IKKα则可部分逆转上述效应（P < 0.05或P < 0.01）。体内实验进一步证实，敲低DLEU2联合抑制EZH2可显著抑制移植瘤生长，增加肿瘤细胞凋亡（均P < 0.01）；IKKα过表达则部分逆转上述抗肿瘤效应（P < 0.05或P < 0.01）。结论：lncRNA DLEU2通过招募EZH2催化H3K27me3修饰，间接激活IKKα/NF-κB信号并形成正反馈环路，介导TPC-1细胞131I抵抗。

AIM:To investigate the modulatory role of E3 ubiquitin-protein ligase ITCH in Alzheimer disease(AD)-like pathology through the thioredoxin-interacting protein(TXNIP)-nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)signaling pathway using both in vivo and in vitro experimental models.METHODS:(1)Ten 5×FAD(AD model)mice and 10 wild-type(WT)mice at 2-,4-and 6-month-old were randomly allocated into AD and WT groups.Amyloid β-protein(Aβ)plaque burden in the brain was detected by thioflavin-S and immunofluorescence staining,with the latter method additionally applied to assess TXNIP protein expression.The protein levels of ITCH and TXNIP were determined by Western blot,while their interaction was verified by co-immunoprecipitation.(2)Mouse mi-croglia BV2 cells stimulated by lipopolysaccharide(LPS)were used to construct neuroinflammation model,and were di-vided into control(CON)group and LPS+ATP treatment group.The BV2 cells stimulated by Aβ were used to construct AD inflammation model.According to the different treatment time,they were divided into CON,and 12,24 and 48 h treatment groups.Western blot was used to evaluate the expression of ITCH,TXNIP,and NLRP3 inflammasome compo-nents(NLRP3 and caspase-1)as well as the downstream IL-1β.Adenovirus-mediated ITCH overexpression(OE-ITCH)in Aβ-stimulated BV2 cells comprised three experimental groups:negative control group,Aβ oligomer stimulation group,and OE-ITCH group,with subsequent immunoblotting of inflammatory mediators.RESULTS:The deposition of Aβ plaques in the cortex and hippocampus of 5×FAD transgenic mice exhibited an age-dependent progression(P<0.01).Compared with WT mice,the levels of TXNIP protein increased synchronously,and the levels of ubiquitin ligase ITCH was significantly down-regulated(P<0.05).Co-immunoprecipitation confirmed the interaction between ITCH and TXNIP proteins in the brain of 2-and 4-month-old 5×FAD mice,which exhibited marked attenuation by 4 months of age.In BV2 microglial models,Aβ/LPS stimulation provoked significant ITCH suppression,concurrently up-regulating TXNIP,core NLRP3 inflammasome components(NLRP3 and caspase-1),and downstream IL-1β(P<0.05).Overexpression of ITCH significantly inhibited Aβ-induced activation of TXNIP and NLRP3 and therelated inflammatory factors in BV2 cells.CONCLUSION:The results of in vitro and in vivo experiments showed that ITCH protein exerts effects against AD-like pathology by inhibiting the expression of TXNIP-NLRP3 signaling pathway.

AIM:To investigate the modulatory role of E3 ubiquitin-protein ligase ITCH in Alzheimer disease(AD)-like pathology through the thioredoxin-interacting protein(TXNIP)-nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)signaling pathway using both in vivo and in vitro experimental models.METHODS:(1)Ten 5×FAD(AD model)mice and 10 wild-type(WT)mice at 2-,4-and 6-month-old were randomly allocated into AD and WT groups.Amyloid β-protein(Aβ)plaque burden in the brain was detected by thioflavin-S and immunofluorescence staining,with the latter method additionally applied to assess TXNIP protein expression.The protein levels of ITCH and TXNIP were determined by Western blot,while their interaction was verified by co-immunoprecipitation.(2)Mouse mi-croglia BV2 cells stimulated by lipopolysaccharide(LPS)were used to construct neuroinflammation model,and were di-vided into control(CON)group and LPS+ATP treatment group.The BV2 cells stimulated by Aβ were used to construct AD inflammation model.According to the different treatment time,they were divided into CON,and 12,24 and 48 h treatment groups.Western blot was used to evaluate the expression of ITCH,TXNIP,and NLRP3 inflammasome compo-nents(NLRP3 and caspase-1)as well as the downstream IL-1β.Adenovirus-mediated ITCH overexpression(OE-ITCH)in Aβ-stimulated BV2 cells comprised three experimental groups:negative control group,Aβ oligomer stimulation group,and OE-ITCH group,with subsequent immunoblotting of inflammatory mediators.RESULTS:The deposition of Aβ plaques in the cortex and hippocampus of 5×FAD transgenic mice exhibited an age-dependent progression(P<0.01).Compared with WT mice,the levels of TXNIP protein increased synchronously,and the levels of ubiquitin ligase ITCH was significantly down-regulated(P<0.05).Co-immunoprecipitation confirmed the interaction between ITCH and TXNIP proteins in the brain of 2-and 4-month-old 5×FAD mice,which exhibited marked attenuation by 4 months of age.In BV2 microglial models,Aβ/LPS stimulation provoked significant ITCH suppression,concurrently up-regulating TXNIP,core NLRP3 inflammasome components(NLRP3 and caspase-1),and downstream IL-1β(P<0.05).Overexpression of ITCH significantly inhibited Aβ-induced activation of TXNIP and NLRP3 and therelated inflammatory factors in BV2 cells.CONCLUSION:The results of in vitro and in vivo experiments showed that ITCH protein exerts effects against AD-like pathology by inhibiting the expression of TXNIP-NLRP3 signaling pathway.

BACKGROUND:In recent years, the technical parameters about hurdle athletes are mainly obtained through video analysis and DLT algorithm. However, the gait and surface electromyography (sEMG) characteristics during normal walking are little reported. OBJECTIVE: To explore the changes of the gait and lower limb sEMG signals relative to gait period in hurdle athletes. METHODS:Eight male professional hurdlers were selected to perform gait and lower limb sEMG tests on the trail, and the differences in gait and sEMG signals were analyzed by mathematical statistics. RESULTS AND CONCLUSION: The gait parameters of hurdlers showed no significant differences (except step length). In the total gait cycle, along with the gait changing, the right and left side muscles of the same name moved alternately. The median frequency and average power frequency of the tapping leg in the lower limb muscles were greater than those of the swinging leg (except biceps femoris, tibialis anterior and lateral gastrocnemius), but the mean EMG and EMG integral values of the tapping leg were smaller than those of the swinging leg. At the stand phase, the median frequency and average power frequency of the tapping leg in the lower limb muscles were greater than those of the swinging leg (except tibialis anterior), but the mean EMG and EMG integral values of the tapping leg were smaller than those of the swinging leg (except soleus). At the swing phase, the median frequency and average power frequency of the tapping leg in the lower limb muscles were greater than those of the swinging leg (except tibialis anterior and lateral gastrocnemius), but the mean EMG and EMG integral values of the tapping leg were smaller than those of the swinging leg (except soleus). To conclude, there are different degrees of differences in the frequency domain and time domain of the lower limb muscles between tapping and swinging legs. Additionally, the muscle strength of the tapping leg is less than that of the swinging leg.