Synergistic effect of all-trans-ret inoic acid and arsenic trioxide on growth inhibition and apoptosis in human hepatoma, breast cancer, and lung cancer cells in vitro

AIM: To investigate the effect of all-trans-retinoic acid (ATRA) on arsenic trioxide (As2O3)-induced apoptosis of human hepatoma, breast cancer, and lung cancer cells in an attempt to find a better combination therapy for solid tumors.METHODS: Human hepatoma cell lines HepG2, Hep3B,human breast cancer cell line MCF-7, and human lung adenocarcinoma cell line AGZY-83-a were treated with As2O3 together with ATRA. Cell survival fraction was determined by MTT assay, cell viability and apoptosis were measured by annexin V-fluorescein isothiocyanate (FITC) and PI staining, and intracellular glutathione (GSH)and glutathione-S-transferase (GST) activities were determined using commercial kits.RESULTS: Cytotoxicity of ATRA was low. ATRA (0.1, 1,and 10 μmol/L) could synergistically potentiate As2O3 to exert a dose-dependent inhibition of growth and to induce apoptosis in each of the cell lines. HepG2 and Hep3B with low intracellular GSH or GST activities were remarkably sensitive to As2O3 or As2O3+ATRA, while AGZY-83-a with higher GSH or GST activities was less sensitive to As2O3or As2O3+ATRA. Treatment with 2 μmol/L As2O3 for 72 h significantly decreased intracellular GSH and GST levels in each of the cell lines, and 1 μmol/L ATRA alone reduced minimal intracellular GSH and GST levels. ATRA potentiated the effect of As2O3 on intracellular GSH levels, but intracellular GST levels were not significantly affected by the combination of As2O3 and ATRA for 72 h as compared to As2O3 alone.CONCLUSION: ATRA can strongly potentiate As2O3-induced growth-inhibition and apoptosis in each of the cell lines, and two drugs can produce a significant synergic effect. The sensitivity to As2O3 or As2O3+ATRA is inversely proportional to intracellular GSH or GST levels in each of the cell lines. The GSH redox system may be the possible mechanism by which ATRA synergistically potentiates As2O3 to exert a dose-dependent inhibition of growth and to induce apoptosis.

Melatonin prevents endothelial cell pyroptosis via regulation of long noncoding RNA MEG3/miR-223/NLRP3 axis

OBJECTIVE To investigate the anti-pyroptotic effects of melatonin in atherosclerotic endothelium and to elucidate the potential mechanisms.METHODS ApoE-/-mice were randomly divid.ed into four groups(n=8):the normal-diet group(ND),the normal-diet group treated with melatonin(10 mg·kg^(-1))(ND+MLT),the high-fat-diet group(HFD),and the high-fat-diet group treated with melatonin(HFD+MLT).After 12 weeks,the expression levels of pyroptosis related genes including NLRP3,ASC,cleaved-caspase 1,GSDMD-N,IL-1β and IL-18 were examined in aortic endothelium by Western blotting,qRT-PCR and immunofluorescent staining.Besides,levels of MEG3 and miR-223 were also tested by qRT-PCR.The interaction between MEG3 and miR-223 was detected by luciferase assay.For in vitro study,human aortic endothelial cells(HAECs) were transiently transfected with miR-223 mimic,miR-223 inhibitor(AMO-223),MEG3-overexpressing plasmid or negative controls.After 6 h of transfection,the medium was replaced by fresh medium with or without ox-LDL(25 μg·mL-1) for 24 h and then treated with or without melatonin(10 μmol·L^(-1)) for 48 h.Cell pyroptosis was evaluated by Hoechst 33342/PI staining and differentially expressed pyroptosis related genes.RESULTS Melatonin markedly reduced the atherosclerotic plaque in aorta of ApoE-/-mice.Meanwhile,melatonin also attenuated the expression NLRP3,ASC,cleaved-caspase1,NF-κB/GSDMD,GSDMD-N termini,IL-1β,and IL-18 in aortic endo.thelium.Consistent anti-pyroptotic effects were also observed in ox-LDL-treated HAECs.We found that lncRNAMEG3 enhanced pyroptosis in HAECs.Moreover,MEG3 acted as an endogenous sponge by sequence complementarity to suppress the function of miR-223 and to increase NLRP3 expression and enhance endothelial cell pyroptosis.Furthermore,knockdown of miR-223 blocked the anti-pyroptotic actions of melatonin in ox-LDL-treated HAECs.CONCLUSION Melatonin prevents endothelial cell pyroptosis via MEG3/miR-223/NLRP3 axis in atherosclerosis and therefore melatonin replacement might be considered a new strategy for protecting endothelium against pyroptosis thereby for the treat.ment of atherosclerosis associated with pyroptosis.

EFFECTS OF ARSENIC TRIOXIDE ADMINISTRATION STYLES ON LEUKOCYTOSIS

客观：学习常常慢的静脉内的三氧化二砷(As2O3 ) 的效果减少的白细胞增多在活体内和在试管内上的注入政体。方法：三种白血病房间， NB4， K562，和尖锐 promyelocytic 白血病(APL ) 房间，分别地在有经常的集中和 As2O3 的变化集中的媒介是有教养的 24 个小时了。七十五个病人随机在二个集团被注册。在试用组，接待的 37 个病人连续地与 8 的注入率减缓静脉内的 As2O3 注入政体 24 个小时每天每大约 18-21 小时的极小、全部的注入持续时间滴下。在控制组， 38 个病人与 45-55 的注入率收到了平淡的政体每天每大约 2-3 小时的极小、全部的注入持续时间滴下 24 个小时。每日的 As2O3 剂量是 0。16 mg/kg。细胞内部的砷集中被原子荧光试金测量。房间， CD33-CD11b+ 房间，和 CD33+CD11b- 房间的 apoptosis 率被流动血细胞计数监视。结果： NB4 ， K562 ，和在有经常的 As2O3 集中的媒介的 APL 白血病房间的 apoptosis 率是56.6%+/-2.4%，27.6%+/-3.1%，和52.2%+/-2.8%，分别地它比有改变 As2O3 集中的那些显著地高(23.2%+/-2.1%，11.0%+/-2.5%，并且21.0%+/-2.5%，分别地 P 【 0.01 )。 APL 的 apoptosis 率， M2 类型尖锐 myeloid ( AML-M2 )，和在试用的长期的 myeloid (电流型逻辑)病人组织(28.5%+/-1.9%，9.5%+/-0.6%，和12.5%+/-1.8%)也比在控制组的那些显著地高(8.5%+/-2.2%，2 。9%+/-0.8% ，和 4.5%+/-1.2% ；P 【 0.05 ) 。在控制组的 CD33 CD11b- 和 CD33-CD11b+ 房间的比率比在试用组的那些显著地高。结论：连续地慢的静脉内的 As2O3 注入政体能获得 apoptosis 和低区别比例的高效率，减轻白细胞增多，并且获得最大的治疗学的利益。

Metabonomic studies of pancreatic cancer response to radiotherapy in a mouse xenograft model using magnetic resonance spectroscopy and principal components analysis

AIM: To investigate the metabolic profiles of xenograft pancreatic cancer before and after radiotherapy by high-resolution magic angle spinning proton magnetic resonance spectroscopy (HRMAS 1H NMR) combined with principal components analysis (PCA) and evaluate the radiotherapeutic effect. METHODS: The nude mouse xenograft model of human pancreatic cancer was established by injecting human pancreatic cancer cell SW1990 subcutaneously into the nude mice. When the tumors volume reached 800 mm3 , the mice received various radiation doses. Two weeks later, tumor tissue sections were prepared for running the NMR measurements. 1H NMR and PCA were used to determine the changes in the metabolic profiles of tumor tissues after radiotherapy. Metabolic profiles of normal pancreas, pancreatic tumor tissues, and radiationtreated pancreatic tumor tissues were compared. RESULTS: Compared with 1H NMR spectra of the normal nude mouse pancreas, the levels of choline, taurine, alanine, isoleucine, leucine, valine, lactate, and glutamic acid of the pancreatic cancer group were increased, whereas an opposite trend for phosphocholine, glycerophosphocholine, and betaine was observed. The ratio of phosphocholine to creatine, and glycerophosphocholine to creatine showed noticeable decrease in the pancreatic cancer group. After further evaluation of the tissue metabolic profile after treatment with three different radiation doses, no significant change in metabolites was observed in the 1H NMR spectra, while the inhibition of tumor growth was in proportion to the radiation doses. However, PCA results showed that the levels of choline and betaine were decreased with the increased radiation dose, and conversely, the level of acetic acid was dramatically increased. CONCLUSION: The combined methods were demonstrated to have the potential for allowing early diagnosis and assessment of pancreatic cancer response to radiotherapy.

Metformin and tanshinone IIA as ethnodrugs protect heart against injury by inhibiting microRNA-1

OBJECTIVE To explore the protection mechanism of metformin and tanshinone IIA on myocardial injury.METHODS The cultured neonatal rat ventricular cells(NRVCs) were exposed to100 μmol·L^(-1) H2 O2 to simulate the in vitro model of ischemia-reperfusion injury.MTT,TUNEL and Viability/Cytotoxicity Assay were used to evaluate the effect of metformin on the viability of cardiomyocytes after treated with H2 O2.The target of miR-1 was verified by Dual luciferase reporter assay.ChIP analyses was adopted to reveal the relationship between C/EBP β and miR-1.Tanshinone IIA was administrated daily for 7 d before ligation of the left anterior descending artery(LAD) and lasted for 3 months after LAD.Whole-cell patch-clamp techniques were used to measure the inward rectifying K+ current(IK1) in rat isolated ventricular myocytes.GRP94,p-AMPKα,C/EBP β,CHOP,Caspase-3,Kir2.1,p38 MAPK,Cx43,MEF2 and SRF levels were analyzed by Western blot and miR-1 level was quantified by Realtime PCR.RESULTS The expression of miR-1 was significantly increased in NRVCs exposed to H2 O2 in vitro.miR-1 was shown to target the 3′-untranslated region(UTR) of GRP94,which results in the accumulation of un/misfolded proteins,leading to the endoplasmic reticulum(ER) stress.C/EBP β directly induces the upregulation of miR-1 by binding to its promoter.Furthermore,metformin,a direct allosteric AMPK activator,significantly reduces C/EBP β and miR-1 levels comparing with control group.Similarly,tanshinone IIA decreased the incidence of arrhythmias and relieved ischemia-induced injury.Moreover,tanshinone IIA depressed the elevated miR-1 level and inhibited the activation of p38 MAPK and heart special transcription factors SRF and MEF2 in ischemic cardiomyocytes.CONCLUSION Metformin protects cardiomyocytes against H2 O2 damage through AMPK/C/EBPβ/miR-1/GRP94 pathway.Tanshi.none IIA play a role in protection cardiomyocytes from ischemic injury based on inhibiting miR-1 expres.sion through p38 MAPK signal pathway.

The ionic mechanisms of long QT interval in diabetic rabbits

与心律不齐联系的客观反常 QT 延伸在糖尿病的病人被认为主要心脏的电的混乱和死亡的一个重要预言者。为糖尿病的 QT 延伸的精确离子的机制仍然保持不清楚。现在的学习被设计在糖尿病的兔子心分析室的极化和内在的离子的机制的变化。方法糖尿病被 alloxan 的单个注射导致(145mg/kg， iv ) 。在糖尿病(10 个星期) 的发展以后， ECG 被测量。整个房间的补丁夹钳技术被使用记录行动潜力持续时间(APD50， APD90 ) ，慢慢地激活的向外修正的钾电流(Iks ) ， L 类型钙水流(Ica-L ) 和里面的修正钾电流(IK1 ) 。室的 myocytes 的行动潜力持续时间(APD50 和 APD90 ) 显然是的结果从 271.5 32.3 ms 延长了并且 347.8 ??  ? 洠瑩 ' 覞湏硺 L 污 ??????? 祭景扩楲獬 ???????? 吗？？

Role of microRNAs in cardiac hypertrophy, myocardial fibrosis and heart failure

MicroRNAs(miRNAs)are endogenous small non-coding RNA molecules that posttranscriptionally regulate gene expression.MiRNA expression and function in heart disease remain to be determined but modulation of miRNA expression in vivo has revealed that miRNAs play an important role in controlling heart function and structure.In fact,abnormal expression of miRNAs may initiate and contribute to the progress of heart disease.Here,we summarize the literature relating to the involvement of miRNAs in cardiac hypertrophy,myocardial fibrosis and heart failure.