下调miR-106a-5p对过氧化氢诱导的心肌细胞损伤及JAK1/STAT3通路的影响

目的 探讨下调miR-106a-5p对过氧化氢(H₂O₂)诱导的心肌细胞损伤及Janus激酶1(JAK1)/信号转导和转录激活因子3(STAT3)通路的影响。方法 不同浓度梯度H₂O₂(0、50、100、200、400μmol/L)处理大鼠心肌细胞H9c2。H9c2细胞分为对照组、H₂O₂组(100μmol/L H₂O₂)、miR-106a-5p NC组(100μmol/L H₂O₂+转染miR-106a-5p NC)和miR-106a-5p siRNA组(100μmol/L H₂O₂+转染miR-106a-5p siRNA)。实时荧光定量PCR(qPCR)法检测miR-106a-5p表达;CCK-8法检测细胞增殖;流式细胞仪检测细胞凋亡;试剂盒检测细胞培养液中乳酸脱氢酶(LDH)含量、谷胱甘肽过氧化物酶(GSH-Px)活性及...     

Inhibition of Dectin-1 in mice ameliorates cardiac remodeling by suppressing NF-κB/NLRP3 signaling after myocardial infarction

The myocardial inflammatory response is a consequence of myocardial infarction (MI), which may deteriorate cardiac remodeling and lead to dysfunction in the heart post-MI. Dectin-1 is a c-type lectin, which has been shown to regulate innate immune responses to pathogens. However, the role of Dectin-1 in the heart diseases remains largely unknown. In this study, we aimed to investigate the effects of Dectin-1 on cardiac remodeling post-MI. We found that cardiac Dectin-1 mRNA and protein expressions were significantly elevated in C57BL/6 mice after MI. In vitro, hypoxia induced cardiomyocyte injury in parallel with increased Dectin-1 protein expression. Knockdown of Dectin-1 remarkably attenuated cardiomyocyte death under hypoxia and lipopolysaccharide (LPS) stimulation. In vivo administration of adeno-associated virus serotype 9 mediated silencing of Dectin-1, which significantly decreased cardiac fibrosis, dilatation, and improved cardiac function in the mice post-MI. At the molecular level, downregulation of Dectin-1 dramatically suppressed up-regulation of nuclear factor-κB (NF-κB), nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3), and the inflammatory genes involved in fibrogenesis and cardiac remodeling after MI. Furthermore, treatment with BAY11-7082, an inhibitor of NF-κB, repressed the activation of NF-κB, and attenuated LPS induced elevation of NLRP3 and cell death in cardiomyocytes. Collectively, upregulation of Dectin-1 in cardiomyocytes post-MI contributes to cardiac remodeling and cardiac dysfunction at least partially by activating NF-κB and NLRP3. This study identified Dectin-1 as a promising therapeutic target for ischemic heart disease.     

Upregulation of miR-144-3p alleviates Doxorubicin-induced heart failure and cardiomyocytes apoptosis via SOCS2/PI3K/AKT axis

MicroRNAs (miRs) are implicated in heart failure (HF). Thereby, we aim to uncover the role of miR-144-3p in HF. Doxorubicin (Dox)-induced HF model was constructed in rats and cardiomyocytes H9C2, and the cardiac function was determined using ultrasound cardiogram. Morphology of cardiac tissue was observed using hematoxylin–eosin (H&E) staining. The viability and apoptosis of Dox-treated and transfected cardiomyocytes were determined using Cell Counting Kit-8 (CCK-8) assay and flow cytometry. Relative expressions of the HF-associated miRs (including miR-144-3p), suppressor of cytokine signaling 2 (SOCS2), apoptosis- and phosphoinositide 3-kinase (PI3K)/AKT pathway-related factors (B-cell lymphoma 2, Bcl-2; Bcl-2 associated X protein, Bax; cleaved [C] capsase-3; phosphoinositide 3-kinase, PI3K; phosphorylated-PI3K, p-PI3K; p-AKT; AKT) were measured with quantitative real-time polymerase chain reaction or Western blot. Target gene of miR-144-3p was predicted by Starbase and TargetScan and confirmed with dual-luciferase reporter assay. Dox caused rat cardiac dysfunction, aggravated cardiac injury, decreased cardiomyocytes viability, and the expression of miR-144-3p, Bcl-2, and phosphorylation of both PI3K and AKT yet the upregulated those of Bax and C caspase-3, which was reversed by upregulating miR-144-3p, whereas downregulating miR-144-3p did oppositely. SOCS2 was the target gene of miR-144-3p, Dox promoted SOCS2 expression, which was reversed by upregulating miR-144-3p, while downregulating miR-144-3p did conversely. In addition, silencing SOCS2 reversed the effects of miR-144-3p downregulation in Dox-treated cardiomyocytes. Upregulating miR-144-3p alleviated Dox-induced cardiac dysfunction and cell apoptosis via targeting SOCS2, providing a novel evidence of miR-144-3p in HF.     

The mouse as a model system to study cardiac regeneration

Cardiomyocytes exhibit robust proliferative activity during development. After birth, cardiomyocyte proliferation is markedly reduced. Consequently, regenerative growth in the postnatal heart via cardiomyocyte proliferation (including, by inference, via proliferation of stem cell-derived cardiomyocytes) is limited and often insufficient to effect repair following injury. Here we review methodologies which employ the mouse as a model system to study cardiac regeneration, and in particular cardiomyocyte replenishment, in health and disease.     

lncRNA OIP5-AS1调节miR-942-5p/CHEK1轴对脑胶质瘤细胞生物学行为的影响

目的 探讨长链非编码RNA(lncRNA)OPA相互作用蛋白5反义转录本1(OIP5-AS1)对脑胶质瘤细胞增殖、凋亡、迁移和侵袭的影响机制。方法 收集33例胶质瘤患者（低级别胶质瘤14例、高级别胶质瘤19例）和33例颅脑损伤患者的组织标本。实时荧光定量PCR(qPCR)检测组织和细胞中OIP5-AS1、微小RNA-942-5p(miR-942-5p)和检查点激酶1(CHEK1)mRNA表达,分析胶质瘤组织中OIP5-AS1、miR-942-5p和CHEK1 mRNA表达水平的相关性。体外培养人脑胶质瘤细胞系U87、SHG-44、U251、H4和正常人星形胶质细胞NHA,Western blot检测细胞中CHEK1蛋白表达。将U87细胞分为对照（NC）组、siRNA阴性对照（si-NC）组、OIP5-AS1 siRNA(si-OIP5-AS1)组、siOIP5-AS1+inhibitor阴性对照（si-OIP5-AS1+anti-NC）组、si-OIP5-AS1+miR-942-5p抑制剂（si-OIP5-AS1+anti-miR-942-5p）组,采用Lipofectamine 30...     

Antidepressant-like activity of the melatonin receptor antagonist, luzindole (N-0774), in the mouse behavioral despair test

The anti-immobility effect of the selective melatonin receptor antagonist, luzindole, was investigated in the behavioral despair test using three different strains (C3H/HeN, C57BL/6J and albino ND/4) of mice. The time of immobility of the C3H/HeN during the 240 s swimming period measured at noon (12:00 to 14:00 h) was 47.8 +/- 3.0 s (n = 63) and at midnight (00:00 to 02:00 h) was 67.7 +/- 2.8 s (n = 68) (P less than 0.001, when compared with the noon value), when the levels of endogenous melatonin are presumably low and high, respectively. Melatonin (30 mg/kg) given i.p. did not modify the time of immobility at either time of measurement. Luzindole (30 mg/kg i.p.) reduced the time of immobility in a dose-dependent manner, the effect being more pronounced at midnight (60% reduction) than at noon (39% reduction). The effect of luzindole was time-dependent, showing a maximal effect at 60 min. The anti-immobility effect of luzindole (10 mg/kg i.p.) was prevented by the administration of melatonin (30 mg/kg i.p.). Luzindole (30 mg/kg i.p.) did not modify the time of immobility either at noon or midnight in the albino ND/4 mouse, or in the C57BL/6J mouse, which does not produce melatonin. Our results suggest that endogenous melatonin plays a role during swimming in the C3H/HeN mouse behavioral despair test. We conclude that luzindole may exert antidepressant-like activity in the C3H/HeN mouse by antagonizing the action of endogenous hormone.     

miR-149-3p在先天性心脏病胎鼠心脏组织中的表达及其对P19细胞分化的影响

目的 探讨miR-149-3p在先天性心脏病（CHD）胎鼠心脏组织中的表达及其对小鼠畸胎瘤P19细胞分化的影响。方法 建立CHD室间隔缺损胎鼠模型,于妊娠第19天,HE染色观察心脏组织病理学变化,实时荧光定量PCR(qPCR)检测心脏组织中miR-149-3p和热休克蛋白蛋白家族B成员6(HSPB6)mRNA表达水平。二甲基亚砜（DMSO）诱导P19细胞向心肌细胞分化,并收集分化第0、5、10天的细胞,qPCR检测诱导分化过程中心肌分化标志物GATA结合蛋白4(GATA4)、心肌肌钙蛋白T(cTnT)、心房利钠尿多肽（ANP）的mRNA表达水平以及HSPB6 mRNA和miR-149-3p表达水平。miR-149-3p过表达慢病毒和空载慢病毒感染P19细胞,DMSO诱导分化第10天,免疫荧光染色检测细胞中cTnI蛋白表达情况,qPCR检测心肌分化相关标志物mRNA表达水平。双荧光素酶报告基因实验验证miR-149-3p与HSPB6之间的靶向关系。结果 与正常组比较,CHD组胎鼠出现心脏室间隔缺损,心脏组织中miR-149-3p高表达,而HSPB6低表达（P<0.01）。P19细胞...     

下丘脑前核微量注射褪黑素及其受体拮抗剂对大鼠血压和心率的影响

目的：研究下丘脑前核微量注射褪黑素及其受体拮抗剂对正常血压和应激性高血压大鼠心血管活动的影响。方法：微量注射褪黑色及其受体拮抗剂至下丘脑前区前核,记录血压、平均动脉压和心率。结果：微量注射褪黑素可降低平均动脉压,其竞争性ML1受体拮抗剂luzindole可完全阻断褪黑素的降压反应,而其ML2受体拮抗剂prazosin不能阻断褪黑素的降压反应。结论：褪黑素为一种降压因子,其降压反应主要通过激活ML1受体,而不是ML2受体来介导的。下丘脑前核是褪黑素影响心血管活动的重要中枢闰。     

LncRNA-MALAT1通过miR-142-3p/TEAD1分子轴调控结直肠癌细胞增殖与凋亡#br#

目的　探讨长链非编码RNA-肺腺癌转移相关转录子1（LncRNA-MALAT1）对结直肠癌细胞增殖与凋亡的影响及相关作用机制。方法　通过Real-time PCR与Western blot实验检测结直肠癌细胞株与人正常结肠上皮细胞中LncRNA-MALAT1、miR-142-3p基因以及TEA结构域转录因子1（TEAD1）蛋白的表达;使用si-MALAT1转染HCT116细胞,在此基础上共转染miR-142-3p inhibitor,利用Real-time PCR与Western blot检测细胞中LncRNA-MALAT1与miR-142-3p基因以及TEAD1、Bax、Bcl-2与Cyclin D1蛋白的表达,通过CCK-8实验检测细胞的增殖水平,通过流式细胞术检测细胞的凋亡水平,通过双荧光素酶实验检测LncRNA-MALAT1与miR-142-3p以及miR-142-3p与TEAD1的结合。结果　与人正常结肠上皮细胞相比,结直肠癌细胞株中LncRNA-MALAT1基因与TEAD1蛋白呈高表达,miR-142-3p基因呈低表达（P＜0.05）;沉默LncRNA-MALAT1能够促进miR-142-3p基因与Bax蛋白表达,抑制LncRNA-MALAT1基因以及Bcl-2、Cyclin D1与TEAD1蛋白表达,抑制细胞增殖,并促进细胞凋亡;在此基础上沉默miR-142-3p能够对上述调控作用实现部分逆转;双荧光素酶实验结果显示,LncRNA-MALAT1与miR-142-3p以及miR-142-3p与TEAD1能够结合。结论　LncRNA-MALAT1能够结合miR-142-3p,促进miR-142-3p靶基因TEAD1表达,进而促进结直肠癌细胞增殖,抑制其细胞凋亡,促进结直肠癌的病理进程。     

Melatonin potentiates tear secretion induced by diadenosine tetraphosphate in the rabbit

Diadenosine tetraphosphate (Ap(4)A, 0.03 nmol) applied topically to the cornea of New Zealand white rabbits, evoked an increase in tear secretion of 9.7 +/- 2.60% (N=7). Melatonin (1 nmol) had no significant effect. Application of Ap(4)A in combination with melatonin, evoked a significantly greater increase in tear secretion of 34.2 +/- 5.8% (N=11). This potentiating effect of melatonin was blocked by pretreating the cornea with a topical application of the melatonin receptor antagonist, luzindole (240 nmol). Melatonin combined with Ap(4)A may be useful for treating dry eye conditions.     

Melatonin Induces Akt Phosphorylation through Melatonin Receptor- and PI3K-Dependent Pathways in Primary Astrocytes

Melatonin has been reported to protect neurons from a variety of neurotoxicity. However, the underlying mechanism by which melatonin exerts its neuroprotective property has not yet been clearly understood. We previously demonstrated that melatonin protected kainic acid-induced neuronal cell death in mouse hippocampus, accompanied by sustained activation of Akt, a critical mediator of neuronal survival. To further elucidate the neuroprotective action of melatonin, we examined in the present study the causal mechanism how Akt signaling pathway is regulated by melatonin in a rat primary astrocyte culture model. Melatonin resulted in increased astrocytic Akt phosphorylation, which was significantly decreased with wortmannin, a specific inhibitor of PI3K, suggesting that activation of Akt by melatonin is mediated through the PI3K-Akt signaling pathway. Furthermore, increased Akt activation was also significantly decreased with luzindole, a non-selective melatonin receptor antagonist. As downstream signaling pathway of Akt activation, increased levels of CREB phoshorylation and GDNF expression were observed, which were also attenuated with wortmannin and luzindole. These results strongly suggest that melatonin exerts its neuroprotective property in astrocytes through the activation of plasma membrane receptors and then PI3K-Akt signaling pathway.     

The long non-coding RNA maternally expressed 3-micorRNA-15a-5p axis is modulated by melatonin and prevents nucleus pulposus cell inflammation and apoptosis

Nucleus pulposus (NP) cell apoptosis is regarded as a critical risk factor for intervertebral disc degeneration (IVDD). Melatonin exerts a protective role on NP cells. The study concentrates on the role and mechanism of lncRNA MEG3 in melatonin-mediated effects on NP cells. An in vitro IVDD model was constructed using IL-1β on human NP cells. qRT-PCR investigated MEG3, miR-15a-5p and PGC-1α mRNA levels in tissues and NP cells. IL-1β-treated NP cells subsequent to transfection, followed by melatonin treatment. NP cell proliferation, viability, apoptosis and inflammatory reactions were assayed. Western blot checked the profiles of PGC-1α, SIRT1 and NF-κB p65. Student's t-test or one-way analysis of variance (ANOVA) followed by Tukey's test was used for statistical tests. As indicated by the data, melatonin weakened NP cell inflammation and apoptosis and enhanced MEG3 expression. MEG3 expression was attenuated in IVDD tissues. MEG3 knockdown impaired the function of melatonin, which was, however, strengthened by miR-15a-5p knockdown. MEG3 targeted miR-15a-5p, which targeted PGC-1α and repressed the PGC-1α/SIRT1 pathway. Collectively, this study has disclosed that the MEG3-miR-15a-5p-PGC-1α/SIRT1 pathway modulated by melatonin can hamper NP cell apoptosis and inflammation elicited by IL-1β.     

Receptor mechanisms involved in the anticonvulsant effect of melatonin in maximal electroshock seizures

The present study investigates the mechanisms involved in the anticonvulsant effect of melatonin in maximum electroshock (MES) seizures. Melatonin (25-100 mg/kg) dose-dependently decreased the duration of tonic hindlimb extension (THLE). The anticonvulsant effect of melatonin was blocked by bicuculline, a GABA(A) receptor antagonist, and luzindole, an ML(1) receptor antagonist, while prazosin, an ML(2) receptor antagonist, enhanced the anticonvulsant actions of melatonin in this seizure model. Administration of serotonergic agents, mianserin and ondansetron, along with melatonin, increased the antiseizurogenic activity of melatonin, while buspirone had no effect. Pretreating the animals with diazepam, carbamazepine or lamotrigine enhanced the anticonvulsant effect of melatonin. Melatonin thus appears to be an effective anticonvulsant, and melatonin ML(1) receptors, GABAergic and serotonergic mechanisms may play an important role in mediating the anticonvulsant activity of melatonin in electroshock seizures.     

Glycogen synthase kinase-3β inhibition alleviates NLRP3 inflammasome activation in myocardial infarction

OBJECTIVE To investigate the regulatory mechanisms of glycogen synthase kinase-3β(GSK-3β)on NLRP3 inflammasome activation. METHODS We conducted myocardial infarction(MI) model in male Sprague-Dawley(SD) rat during days 2-28. An in vitro investigation was performed using new-born rat/human cardiomyocyte and fibroblast cultures under typical inflammasome stimulation and hypoxia treatment. Further identification for possibility of GSK-3β active NLRP3 inflammasomes, GSK-3β immunoprecipitation was performed from the lysate of inflammasome stimulation-treated rat neonatal fibroblasts(RCFs) with or without GSK-3β inhibitor pretreatment. RESULTS Assessments of cardiac function, histochemical and biochemical assays for cardiac tissues, as well as detection of protein and m RNA expressions in heart tissues, showed that GSK-3β inhibition remarkably improves myocardial dysfunction and prevents remodeling with parallel reduction of the parameters of NLRP3 inflammasome activation after MI. The measurement of primary rats/human cells expounded that GSK-3β inhibition reduce NLRP3 inflammasome activation happens in cardiac fibroblasts, but not in cardiomyocytes. Futhermore, GSK-3β interacts with ASC and GSK-3β inhibition reduces cytoplasmic aggregates of ASC, NLRP3 and caspase-1 formation. CONCLUSION GSK-3β directly mediates NLRP3 inflammasome activation causing cardiac dysfunction in MI.     

Neovascularization and cardiac repair by bone marrow-derived stem cells

Postinfarction congestive heart failure with impaired systolic left ventricular function is a loss of cardiomyocyte disease. Adult stem or progenitor cells from the bone marrow and the peripheral blood have been experimentally shown to differentiate towards endothelial cells and cardiomyocytes under the appropriate conditions. The use of autologous adult stem cells for neovascularization and cardiac regeneration is a promising concept and has shown benefit in pilot clinical trails enrolling postinfarction patients with coronary artery disease. Cell therapy may act through differentiation into and thus replacement of cardiomyocytes and/or neovascularization, the formation of new vessels in the adult organism. Moreover, the release of factors acting in a paracrine manner may contribute to neovascularization and scar remodelling. In this review, the experimental data regarding neovascularization and cardiomyocyte formation from adult stem/progenitor cells are discussed.     

MiR-22-3p in exosomes increases the risk of heart failure after down-regulation of FURIN

Heart failure (HF) is often the inevitable manifestation of myocardial ischemia. Hypoxia can induce cardiomyocytes to express many microRNAs (miRNAs), which are highly expressed in exosomes. In addition, miR-22-3p is a marker in heart failure. Therefore, miR-22-3p was taken as the research object to explore its role and mechanism in HF. HF differentially expressed miRNAs were screened by bioinformatic analysis. The HF rats model was constructed and identified by detecting serum brain natriuretic peptide (BNP) and ultrasound analysis [left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS)]. The extracted exosomes were identified by transmission electron microscopy, and Western blot was used to detect the expressions of Tsg101 and CD63. Quantitative real-time polymerase chain reaction detected miR-22-3p expression in serum, exosomes, and serum without exosomes, while the cardiomyocytes cytotoxicity was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and PKH26 staining. After overexpressing/silencing miR-22-3p in cells, cell viability, apoptosis, and apoptosis-associated markers were detected. Bioinformatic analysis screened the target gene of miR-22-3p, which was verified by dual-luciferase assay. Regulation of miR-22-3p on FURIN was measured by rescue tests. In vivo experiments were verified the above results. MiR-22-3p was identified as the research object. BNP was increased in the model group, while LVEF and LVFS were decreased. MiR-22-3p was overexpressed in HF-treated serum and exosomes. Normal exosomes did not affect cardiomyocyte function, while high concentrations of HF-treated exosomes were cytotoxic. By regulating apoptosis-related genes, overexpressed miR-22-3p inhibited cell activity and promoted cell apoptosis. Silenced miR-22-3p with opposite effects counteracted effects of HF-treated exosomes. FURIN, target gene of miR-22-3p, was negatively regulated by miR-22-3p, while overexpressed FURIN promoted cell activity and inhibited apoptosis. In vivo research was consistent with the results of cell experiments. By regulating FURIN, miR-22-3p in exosomes increases the risk of HF damage.     

MicroRNA-34c-5p provokes isoprenaline-induced cardiac hypertrophy by modulating autophagy via targeting ATG4B

Pathological cardiac hypertrophy serves as a significant foundation for cardiac dysfunction and heart failure. Recently, growing evidence has revealed that microRNAs (miRNAs) play multiple roles in biological processes and participate in cardiovascular diseases. In the present research, we investigate the impact of miRNA-34c-5p on cardiac hypertrophy and the mechanism involved. The expression of miR-34c-5p was proved to be elevated in heart tissues from isoprenaline (ISO)-infused mice. ISO also promoted miR-34c-5p level in primary cultures of neonatal rat cardiomyocytes (NRCMs). Transfection with miR-34c-5p mimic enhanced cell surface area and expression levels of foetal-type genes atrial natriuretic factor (Anf) and β-myosin heavy chain (β-Mhc) in NRCMs. In contrast, treatment with miR-34c-5p inhibitor attenuated ISO-induced hypertrophic responses. Enforced expression of miR-34c-5p by tail intravenous injection of its agomir led to cardiac dysfunction and hypertrophy in mice, whereas inhibiting miR-34c-5p by specific antagomir could protect the animals against ISO-triggered hypertrophic abnormalities. Mechanistically, miR-34c-5p suppressed autophagic flux in cardiomyocytes, which contributed to the development of hypertrophy. Furthermore, the autophagy-related gene 4B (ATG4B) was identified as a direct target of miR-34c-5p, and miR-34c-5p was certified to interact with 3′ untranslated region of Atg4b mRNA by dual-luciferase reporter assay. miR-34c-5p reduced the expression of ATG4B, thereby resulting in decreased autophagy activity and induction of hypertrophy. Inhibition of miR-34c-5p abolished the detrimental effects of ISO by restoring ATG4B and increasing autophagy. In conclusion, our findings illuminate that miR-34c-5p participates in ISO-induced cardiac hypertrophy, at least partly through suppressing ATG4B and autophagy. It suggests that regulation of miR-34c-5p may offer a new way for handling hypertrophy-related cardiac dysfunction.     

Involvement of melatonin MT(3) receptors in the regulation of intraocular pressure in rabbits

Melatonin, a neurohormone secreted by the pineal gland, can stimulate three subtypes of receptors, namely: mt(1), MT(2) and MT(3). We examined the ability of melatonin and the selective MT(3) receptor agonist, 5-methoxycarbonylamino-N-acetyltryptamine (5-MCA-NAT), to modify intraocular pressure in rabbits. Both compounds significantly reduced intraocular pressure, maximally by 24% and 43%, respectively, with IC(50) values of 363+/-23.0 and 423+/-30.0 ng/10 microl (1.6+/-0.1 and 1.8+/-0.1 nmol, respectively). The non-specific melatonin receptor antagonist, luzindole, abolished the depressant effect of both compounds, thus confirming the involvement of melatonin receptors. Our results show, for the first time, a functional response that may be regulated by melatonin MT(3) receptors, and provide evidence that supports a role of melatonin in the circadian changes of intraocular pressure.     

长链非编码 RNA膀胱癌相关转录物 1对微小 RNA-503-5p的靶向关系及对结直肠癌细胞增殖和凋亡的影响

目的 研究长链非编码RNA(lncRNA)膀胱癌相关转录物1(BLACAT1)对微小RNA(miR)-503-5p的靶向关系及结直肠癌细胞增殖和凋亡的影响.方法 实时荧光定量PCR(qRT-PCR)检测结肠癌细胞株SW620,LOVO,HT29和人正常结肠黏膜上皮细胞株NCM460中BLACAT1和miR-503-5p的表达.在HT29细胞中转染si-BLACAT1、pcDNA-BLACAT1或miR-503-5p,噻唑蓝(MTT)检测细胞增殖,流式细胞术检测细胞凋亡,蛋白质印迹法(Western blotting)检测细胞核相关抗原Ki-67(Ki-67)、细胞周期蛋白D1(Cyclin D1)、活化的多聚ADP-核糖聚合酶(Cleaved PARP)和活化的含半胱氨酸的天冬氨酸蛋白水解酶-3(Cleaved caspase-3)的表达,starbase预测和双荧光素酶报告分析BLACAT1与miR-503-5p之间的靶向关系.si-BLACAT1和anti-miR-503-5p共转染,观察干扰miR-503-5p对沉默BLACAT1诱导的结直肠癌细胞增殖和凋亡的影响.结果 与NCM460细胞比较,SW620、LOVO和HT29中BLACAT1表达量明显增加[(4.93±0.58)、(5.66±0.53)、(6.17±0.66)比(1.03±0.22)],miR-503-5p表达量减少[(0.72±0.11)、(0.67±0.09)、(0.51±0.08)比(1.04±0.14)](P<0.05).沉默BLACAT1或转染miR-503-5p明显减少HT29细胞的细胞存活率、Ki-67、CyclinD1蛋白表达量,提高细胞凋亡率、Cleaved PARP和Cleaved caspase-3蛋白水平(P<0.05),过表达BLACAT1则反之.BLACAT1靶向miR-503-5p调控其表达.干扰miR-503-5p部分逆转沉默BLACAT1抑制结直肠癌细胞增殖、Ki-67、CyclinD1蛋白表达和诱导结直肠癌细胞凋亡、Cleaved PARP、Cleaved caspase-3蛋白表达的作用.结论 lncRNA BLA-CAT1在表达上调,沉默BLACAT1可通过靶向调控miR-503-5p的表达,来抑制结直肠癌细胞增殖,并诱导细胞凋亡.     

Influence of exogenous melatonin on doxorubicin-evoked effects in myocardium and in transplantable Morris hepatoma in rats

BACKGROUND: Melatonin is one of the most effective oxygen free radical scavengers. Its cardio- and nephro-protective effects were demonstrated in the course of anthracycline administration. The present study aimed at examining the cytostatic efficiency of doxorubicin (DOX) applied together with melatonin to rats with transplantable Morris hepatoma. MATERIALS AND METHODS: Animals were divided into four groups receiving 0.9% NaCl, melatonin, DOX and melatonin together with DOX, respectively. Three weeks after transplantation of the tumour cells, the heart and tumour were isolated. The extent of tumour necrosis and the number of apoptotic cells were evaluated in paraffin-embedded sections. RESULTS: Administration of melatonin together with DOX decreased the extent of tumour necrosis and the apoptotic tumour cells but, on the other hand, decreased the number of apoptotic cardiomyocytes. CONCLUSION: Melatonin weakens the cytotoxic activity of DOX by the decreased proportions of necrotic and apoptotic cells of transplantable Morris hepatoma. Melatonin protects also cardiomyocytes by decreasing DOX-induced apoptosis in the cells.