Lysine-specific demethylase 1 inhibitor rescues the osteogenic ability of mesenchymal stem cells under osteoporotic conditions by modulating H3K4 methylation

Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulation plays an important role in the developmental origins of osteoporosis; however, few studies have investigated the potential of epigenetic therapy to improve or rescue the osteogenic ability of bone marrow mesenchymal stem cells(BMMSCs) under osteoporotic conditions. Here, we investigated pargyline, an inhibitor of lysine-specific demethylase 1(LSD1), which mainly catalyzes the demethylation of the di- and mono-methylation of H3K4. We demonstrated that 1.5 mmol·Lpargyline was the optimal concentration for the osteogenic differentiation of human BMMSCs. Pargyline rescued the osteogenic differentiation ability of mouse BMMSCs under osteoporotic conditions by enhancing the dimethylation level of H3K4 at the promoter regions of osteogenesis-related genes. Moreover, pargyline partially rescued or prevented the osteoporotic conditions in aged or ovariectomized mouse models, respectively. By introducing the concept of epigenetic therapy into the field of osteoporosis, this study demonstrated that LSD1 inhibitors could improve the clinical practice of MSC-based bone tissue engineering and proposes their novel use to treat osteoporosis.

Lysine-specific demethylase 1 expression in zebrafish during the early stages of neuronal development

Lysine-specific demethylase 1 （Lsdl） is associated with transcriptional coregulation via the modulation of histone methylation. The expression pattern and function of zebrafish Lsdl has not, however, been studied. Here, we describe the pattern of zebrafish Lsdl expression during different development stages. In the zebrafish embryo, Isdl mRNA was present during the early cleavage stage, indicating that maternally derived Lsdl protein is involved in embryonic patterning. During embryogenesis from 0 to 48 hours post-fertilization （hpf）, the expression of Isdl mRNA in the embryo was ubiquitous before 12 hpf and then became restricted to the antedor of the embryo （particularly in the brain） from 24 hpf to 72 hpf. Inhibition of Lsdl activity （by exposure to tranylcypromine） or knockdown of Isdl expression （by morpholino antisense oligonucleotide injection） led to the loss of cells in the brain and to a dramatic downregulatJon of neural genes, including gad65, gad75, and reelin, but not hey1. These findings indicate an important role of Lsdl during nervous system development in zebrafish.

Mitochondrial pathway of the lysine demethylase 5C inhibitor CPI-455 in the Eca-109 esophageal squamous cell carcinoma cell line

BACKGROUND Esophageal cancer is a malignant tumor of the digestive tract that is difficult to diagnose early.CPI-455 has been reported to inhibit various cancers,but its role in esophageal squamous cell carcinoma(ESCC)is unknown.AIM To investigate the effects and mechanism of the lysine demethylase 5C inhibitor,CPI-455,on ESCC cells.METHODS A methyl tetrazolium assay was used to detect the inhibitory effect of CPI-455 on the proliferation of Eca-109 cells.Apoptosis,reactive oxygen species(ROS),and mitochondrial membrane potential were assessed by flow cytometry.Laser confocal scanning and transmission electron microscopy were used to observe changes in Eca-109 cell morphology.The protein expression of P53,Bax,lysinespecific demethylase 5C(KDM5C),cleaved Caspase-9,and cleaved Caspase-3 were assayed by western blotting.RESULTS Compared with the control group,CPI-455 significantly inhibited Eca-109 cell proliferation.Gemcitabine inhibited Eca-109 cell proliferation in a concentrationand time-dependent manner.CPI-455 caused extensive alteration of the mitochondria,which appeared to have become atrophied.The cell membrane was weakly stained and the cytoplasmic structures were indistinct and disorganized,with serious cavitation when viewed by transmission electron microscopy.The flow cytometry and western blot results showed that,compared with the control group,the mitochondrial membrane potential was decreased and depolarized in Eca-109 cells treated with CPI-455.CPI-455 significantly upregulated the ROS content,P53,Bax,Caspase-9,and Caspase-3 protein expression in Eca-109 cells,whereas KDM5C expression was downregulated.CONCLUSION CPI-455 inhibited Eca-109 cell proliferation via mitochondrial apoptosis by regulating the expression of related genes.

Histone demethylase JMJD3 downregulation protects against aberrant force-induced osteoarthritis through epigenetic control of NR4A1

Osteoarthritis(OA)is a prevalent joint disease with no effective treatment strategies.Aberrant mechanical stimuli was demonstrated to be an essential factor for OA pathogenesis.Although multiple studies have detected potential regulatory mechanisms underlying OA and have concentrated on developing novel treatment strategies,the epigenetic control of OA remains unclear.Histone demethylase JMJD3 has been reported to mediate multiple physiological and pathological processes,including cell differentiation,proliferation,autophagy,and apoptosis.However,the regulation of JMJD3 in aberrant force-related OA and its mediatory effect on disease progression are still unknown.In this work,we confirmed the upregulation of JMJD3 in aberrant forceinduced cartilage injury in vitro and in vivo.Functionally,inhibition of JMJD3 by its inhibitor,GSK-J4,or downregulation of JMJD3 by adenovirus infection of sh-JMJD3 could alleviate the aberrant force-induced chondrocyte injury.Mechanistic investigation illustrated that aberrant force induces JMJD3 expression and then demethylates H3K27me3 at the NR4A1 promoter to promote its expression.Further experiments indicated that NR4A1 can regulate chondrocyte apoptosis,cartilage degeneration,extracellular matrix degradation,and inflammatory responses.In vivo,anterior cruciate ligament transection(ACLT)was performed to construct an OA model,and the therapeutic effect of GSK-J4 was validated.More importantly,we adopted a peptide-si RNA nanoplatform to deliver si-JMJD3 into articular cartilage,and the severity of joint degeneration was remarkably mitigated.Taken together,our findings demonstrated that JMJD3 is flow-responsive and epigenetically regulates OA progression.Our work provides evidences for JMJD3 inhibition as an innovative epigenetic therapy approach for joint diseases by utilizing p5RHH-si RNA nanocomplexes.

2-甲基-2-取代-7-羟基-2,3-二氢-4H-1-苯骈吡喃-4-酮及其

目的:对自行设计的抗真菌先导化合物进行衍生物合成和抗真菌活性研究,以验证设计思想,检验模建结果的可靠性。方法:设计合成18个化合物,所有目标化合物经元素分析、1HNMR谱和红外光谱确证,部分化合物还进一步用13CNMR谱、MSEI谱和高分辨质谱确证。用8种人类致病真菌对所有目标化合物测试体外最小抑菌浓度值。结果:合成的18个化合物中,14个(JS1b～d,JS2a～d,JS3a～b,JS4a～d和JS5c)为新化合物。结论:对所合成的化合物进行抗真菌活性测试,结果表明设计合成的衍生物的抗真菌活性变化规律与设计思想吻合,从配体角度验证了模建的靶酶三维结构的可靠性,检测了活性位点力场的分布。

组蛋白去甲基化酶家族中组蛋白去甲基化酶4作用机制及其应用的研究进展

组蛋白甲基化是一种重要的表观遗传性修饰方式,是一个可逆的动态调节过程。组蛋白去甲基化酶家族中组蛋白去甲基化酶4能催化去除组蛋白赖氨酸残基甲基标记,调节染色质的结构,参与精细调控基因转录,维持染色质的活性和非活性平衡。组蛋白去甲基化酶4异常可能导致细胞增殖、分化、个体发育、能量代谢及肿瘤发生发展等多种生物进程异常。研究显示组蛋白去甲基化酶4可作为新的药物靶标。本文就组蛋白去甲基化酶4家族的结构、作用机制、在疾病发生发展进程中的生物学功能及特异性抑制剂开发的最新研究进展作一综述。

LSD1、NUSAP1和TEAD4在人乳头瘤病毒感染尖锐湿疣及宫颈癌中的表达及意义

目的观察组蛋白赖氨酸去甲基化酶1(histone lysines demethylase 1,LSD1)、核仁纺锤体相关蛋白1(nucleolar and spindle-associated protein 1,NUSAP1)和转录增强因子4(TEA domain transcription factor4,TEAD4)在低危型、高危型人乳头瘤病毒(HPV)感染尖锐湿疣组织及宫颈鳞状细胞癌(宫颈癌)组织中的表达变化及其临床意义。方法采用免疫组化法分别检测LSD1、NUSAP1和TEAD4在30例宫颈癌组织、30例高危型HPV感染尖锐湿疣组织、30例低危型HPV感染尖锐湿疣组织以及10例正常宫颈组织中的表达情况。结果宫颈癌组、高危型组、低危型组、正常对照组中LSD1阳性率分别为76.67%、53.33%、16.67%、0.00%,NUSAP1阳性率分别为90.00%、56.67%、20.00%、0.00%,TEAD4阳性率分别为86.67%、50.00%、13.33%、0.00%;组间多重比较结果显示,与正常对照组相比,宫颈癌组、高危型组LSD1、NUSAP1和TEAD4表达水平均显著升高:与低危型组相比,宫颈癌组、高危型组LSD1、NUSAP1和TEAD4表达水平均显著升高:与高危型组相比,宫颈癌组NUSAP1和TEAD4表达水平均显著升高:与高危型组相比,宫颈癌组LSD1的表达差异无显著性:与正常对照组相比,低危型组LSD1、NUSAP1和TEAD4的表达差异无显著性。结论LSD1、NUSAP1、TEAD4参与了高危型HPV感染向宫颈癌的发展,可能成为宫颈癌研究的新思路。

N-甲基(3,4-亚甲二氧基苯甲酰)甲基-乙酰胺(SY-640)对化学致癌剂苯并芘与小鼠肝细胞核DNA共价结合的抑制作用

用小鼠肝细胞核制备和肝微粒体制备，研究了化合物ＳＹ６４０对致癌剂苯并芘（ＢＰ）损伤肝细胞核的保护作用及与Ｐ４５０的关系。结果表明，ＳＹ６４０可显著抑制３ＨＢＰ与小鼠肝细胞核的ＤＮＡ共价结合。ＳＹ６４０连续ｐｏ３ｄ，可显著诱导小鼠肝微粒体细胞色素Ｐ４５０含量及氨基比林脱甲基酶活性；给药１次２ｈ内却只抑制氨基比林脱甲基酶活性。体外温孵实验表明，ＳＹ６４０对小鼠肝微粒体氨基比林脱甲基酶活性也具有明显的抑制作用。差示光谱分析表明，ＳＹ６４０可与细胞色素Ｐ４５０形成络合物。提示该化合物对肝微粒体细胞色素Ｐ４５０酶系的影响与其对化学致癌剂ＢＰ所致肝细胞毒性的保护作用有关。

卵巢癌组织中LSD1、NDRG1基因表达量与癌细胞迁移、侵袭的相关性研究

目的:研究卵巢癌组织中赖氨酸特异性组蛋白去甲基化酶1(lysine-specific demethylase 1,LSD1)、N-myc下游调节基因1(N-myc downstream regulated 1,NDRG1)基因表达量与癌细胞迁移、侵袭的相关性。方法:选择2014年3月~2017年7月扶风县人民医院接受手术切除的卵巢癌患者作为研究对象,手术切除后取卵巢癌组织和癌旁组织,测定LSD1、NDRG1基因及迁移基因、侵袭基因的表达量。结果:卵巢癌组织中LSD1、YKL40、COX2、Twist、IFITM1、CatL、CTHRC1、MMP2、FUNDC1基因的mRNA表达量显著高于癌旁组织,NDRG1、E-cadherin、Wnt5a基因的mRNA表达量显著低于癌旁组织;LSD1高表达的卵巢癌组织中YKL40、COX2、Twist、IFITM1、CatL、CTHRC1、MMP2、FUNDC1的mRNA表达量显著高于LSD1低表达的卵巢癌组织,E-cadherin、Wnt5a基因的mRNA表达量显著低于LSD1低表达的卵巢癌组织。结论:卵巢癌组织中LSD1高表达、NDRG1低表达能够促进癌细胞的迁移、侵袭。

Correlation of LSD1 and NDRG1 gene expression in ovarian cancer tissue with cancer cell migration and invasion

Objective: To study the correlation of LSD1 and NDRG1 gene expression in ovarian cancer tissue with cancer cell migration and invasion. Methods: Patients with ovarian cancer who underwent surgical resection in Fufeng County People's Hospital between March 2014 and July 2017 were selected as the research subjects, and the ovarian cancer tissue and adjacent tissue were collected after surgical resection to determine the expression of LSD1, NDRG1, migration genes and invasion genes. Results: LSD1, YKL40, COX2, Twist, IFITM1, CatL, CTHRC1, MMP2 and FUNDC1 mRNA expression in ovarian cancer tissue were significantly higher than those in adjacent tissue whereas NDRG1, E-cadherin and Wnt5a mRNA expression were significantly lower than those in adjacent tissue;YKL40, COX2, Twist, IFITM1, CatL, CTHRC1, MMP2 and FUNDC1 mRNA expression in ovarian cancer tissue with high LSD1 expression were significantly higher than those in ovarian tissue with low LSD1 expression whereas E-cadherin and Wnt5a gene mRNA expression were significantly lower than those in ovarian tissue with low LSD1 expression. Conclusion: The high LSD1 expression and low NDRG1 expression in ovarian cancer tissue can promote the migration and invasion of cancer cells.

Correlation of LSD1 and PARP1 with cell proliferation and epithelial-mesenchymal transition in ovarian cancer tissue from ultrasound-guided puncture

Objective: To study the correlation of LSD1 and PARP1 with cell proliferation and epithelial-mesenchymal transition in ovarian cancer tissue from ultrasound-guided puncture. Methods:The ovarian cancer and ovarian benign lesion tissue from ultrasound-guided puncture in Pangang Group General Hospital in Panzhihua between May 2014 and March 2017 were collected to detect the mRNA expression of LSD1 and PARP1 as well as the protein levels of cell proliferation molecules and epithelial-mesenchymal transition molecules in them. Results: LSD1 and PARP1 mRNA expression in ovarian cancer tissue were significantly higher than those in benign ovarian tissue;P21, P27 and E-cadherin protein levels in ovarian cancer tissue were significantly lower than those in benign ovarian tissue while CyclinD1, E2F, Twist1, Snail, Slug and N-cadherin protein levels were significantly higher those in benign ovarian tissue;P21 and P27 protein levels in the ovarian cancer tissue with high LSD1 expression were significantly lower than those in the ovarian cancer tissue with low LSD1 expression while CyclinD1 and E2F protein levels were significantly higher than those in the ovarian cancer tissue with low LSD1 expression;Twist1, Snail, Slug and N-cadherin protein levels in the ovarian cancer tissue with high PARP1 expression were significantly higher than those in the ovarian cancer tissue with low PARP1 expression while E-cadherin protein level was significantly lower than that in the ovarian cancer tissue with low PARP1 expression. Conclusion: The LSD1 and PARP1 highly expressed in ovarian cancer tissue can promote the proliferation and epithelial-mesenchymal transition of cancer cells.

The PHD1 finger of KDM5B recognizes unmodified H3K4 during the demethylation of histone H3K4me2/3 by KDM5B

KDM5B is a histone H3K4me2/3 demethylase. The PHD1 domain of KDM5B is critical for demethylation, but the mechanism underlying the action of this domain is unclear. In this paper, we observed that PHDIKDMSB interacts with unmethylated H3K4me0. Our NMR structure of PHDIKDMSB in complex with H3K4me0 revealed that the binding mode is slightly different from that of other reported PHD fingers. The disruption of this interaction by double mutations on the residues in the interface （L325A/D328A） decreases the H3K4me2/3 demethylation activity of KDM5B in cells by approximately 50% and increases the transcriptional repression of tumor suppressor genes by approximately twofold. These findings imply that PHDIKDMSB may help maintain KDM5B at target genes to mediate the demethylation activities of KDM5B.