Search

Purpose: Epigenetic therapy has had a significant impact on the management of haematologic malignancies. The aim of this study was to assess whether 5-aza-CdR and TSA inhibit the growth of leukaemia cells and induce caspase-3-dependent apoptosis by upregulating RUNX3 expression., Methods: K562 and Reh cells were treated with 5-aza-CdR, TSA or both compounds. RT-PCR and Western blot analyses were used to examine the expression of RUNX3 at the mRNA and protein levels, respectively. Immunofluorescence microscopy was used to detect the cellular location of RUNX3. Additionally, after K562 cells were transfected with RUNX3, apoptosis and proliferation were studied using Annexin V staining and MTT assays., Results: The expression of RUNX3 in leukaemia cell lines was markedly less than that in the controls. Demethylating drug 5-aza-CdR could induce RUNX3 expression, but the combination of TSA and 5-aza-CdR had a greater effect than did treatment with a single compound. The combination of 5-aza-CdR and TSA induced the translocation of RUNX3 from the cytoplasm into the nucleus. TSA enhanced apoptosis induced by 5-aza-CdR, and Annexin V and Hoechst 33258 staining showed that the combination induced apoptosis but not necrosis. Furthermore, apoptosis was dependent on the caspase-3 pathway. RUNX3 overexpression in K562 cells led to growth inhibition and apoptosis and potentiated the effects of 5-aza-CdR induction., Conclusion: RUNX3 plays an important role in leukaemia cellular functions, and the induction of RUNX3-mediated effects may contribute to the therapeutic value of combination TSA and 5-aza-CdR treatment.

1. Suppressing apoptosis and downregulating K(+) channels in pulmonary artery smooth muscle cells (PASMC) have been implicated in the development of pulmonary vascular medial hypertrophy and pulmonary arterial hypertension (PAH). Previous studies have shown that selective serotonin re-uptake inhibitors (SSRIs) protected against PAH. The aim of the present study was to investigate the involvement of Kv1.5 channels and apoptosis in the protective effect of the SSRI fluoxetine against PAH. 2. Monocrotaline (MCT) was used to establish PAH in Wistar rats. Fluoxetine (2 and 10 mg/kg per day) was administered by gavage once a day for 3 weeks. Three weeks after the induction of PAH by MCT, pulmonary haemodynamic measurements and pulmonary artery morphological assessments were undertaken, along with detection of apoptosis and Kv1.5. 3. Fluoxetine (2 and 10 mg/kg per day) decreased pulmonary artery pressure, reduced the right ventricular index and inhibited the increase in medial wall thickness of pulmonary arteries in established PAH. Fluoxetine (10 mg/kg per day) reduced the expression of Bcl-2 and Bcl-xL protein, increased the expression of cleaved caspase 3 protein and enhanced the expression of Kv1.5 protein and mRNA in pulmonary arteries. Furthermore, fluoxetine (10 mg/kg per day) significantly suppressed proliferation and enhanced apoptosis of PASMC in MCT-induced PAH. 4. In conclusion, fluoxetine protects against MCT-induced PAH by suppressing PASMC proliferation, inducing PASMC apoptosis and upregulating Kv1.5 channels.

This study aimed to establish the role of miR-129 and miR-384-5p in cerebral ischemia-induced apoptosis. Using PC12 cells transfected with miR-129 or miR-384-5p mimics or inhibitors, oxygen glucose deprivation (OGD) conditions were applied for 4 h to simulate transient cerebral ischemia. Apoptotic phenotypes were assessed via lactate dehydrogenase (LDH) assay, MTT cell metabolism assay, and fluorescence-activated cell sorting (FACS). The effect of miR overexpression and inhibition was evaluated by protein and mRNA detection of bcl-2 and caspase-3, critical apoptosis factors. Finally, the direct relationship of miR-129 and bcl-2 and miR-384-5p and caspase-3 was measured by luciferase reporter assay. The overexpression of miR-384-5p and miR-129 deficiency significantly enhanced cell viability, reduced LDH release, and inhibited apoptosis. By contrast, overexpression of miR-129 and miR-384-5p deficiency aggravated hypoxia-induced apoptosis and cell injury. miR-129 overexpression significantly reduced mRNA and protein levels of bcl-2 and miR-129 inhibition significantly increased mRNA and protein levels of bcl-2 in hypoxic cells.miR-384-5p overexpression significantly reduced protein levels of caspase-3 while miR-384-5p deficiency significantly increased protein levels of caspase-3. However, no changes were observed in caspase-3 mRNA in either transfection paradigm. Finally, luciferase reporter assay confirmed caspase-3 to be a direct target of miR-384-5p; however, no binding activity was detected between bcl-2 and miR-129.Transient cerebral ischemia induces differential expression of miR-129 and miR-384-5p which influences apoptosis by regulating apoptotic factors caspase-3 and bcl-2, thereby participating in the pathological mechanism of cerebral ischemia, and becoming potential targets for the treatment of ischemic cerebral injury in the future. [ABSTRACT FROM AUTHOR]

Rasmussen encephalitis (RE) is a severe pediatric inflammatory brain disease characterized by unilateral inflammation and atrophy of the cerebral cortex, drug‐resistant focal epilepsy and progressive neurological and cognitive deterioration. The etiology and pathogenesis of RE remain unclear. Our previous results demonstrated that the adenosine A1 receptor (A1R) and the major adenosine‐removing enzyme adenosine kinase play an important role in the etiology of RE. Because the downstream pathways of inhibitory A1R signaling are modulated by stimulatory A2AR signaling, which by itself controls neuro‐inflammation, glial activation and glial glutamate homeostasis through interaction with glutamate transporter GLT‐1, we hypothesized that maladaptive changes in adenosine A2A receptor (A2AR) expression are associated with RE. We used immunohistochemistry and Western blot analysis to examine the expression of A2ARs, glutamate transporter‐I (GLT‐1) and the apoptotic marker Bcl‐2 in surgically resected cortical specimens from RE patients (n = 18) in comparison with control cortical tissue. In lesions of the RE specimen we found upregulation of A2ARs, downregulation of GLT‐1 and increased apoptosis of both neurons and astroglia. Double staining revealed colocalization of A2ARs and Bcl‐2 in RE lesions. These results suggest that maladaptive changes in A2AR expression are associated with a decrease in GLT‐I expression as a possible precipitator for apoptotic cell loss in RE. Because A2AR antagonists are already under clinical evaluation for Parkinson's disease, the A2AR might likewise be a tractable target for the treatment of RE. [ABSTRACT FROM AUTHOR]

ContextAsiatic acid, a triterpenoid compound extracted from the tropical medicinal plantCentella asiatica(Family: Apiaceae), has exhibited various biological activities. ObjectiveThis study was performed to investigate the cytotoxic effects of asiatic acid on human ovarian cancer cells. Materials and methodsSKOV3 and OVCAR-3 ovarian cancer cells were exposed to different concentrations of asiatic acid (10–100 μg/mL) for 72 or 48 h. Cell viability, colony formation, cell cycle distribution, apoptotic response were examined. Involvement of the phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway was tested. ResultsAt the concentration of 40 μg/mL, asiatic acid caused about 50% reduction in the viability of ovarian cancer cells, but had little effect on the viability of normal human ovarian epithelial cells. Asiatic acid at 10 μg/mL reduced colony formation of ovarian cancer cells by 25–30%. Asiatic acid-treated cells showed a cell cycle arrest at the G0/G1 phase and 7- to 10-fold increase in apoptosis. The phosphorylation levels of PI3K, Akt and mTOR were remarkably lower in asiatic acid-treated cells. Overexpression of constitutively active Akt partially reversed the cytotoxic effects of asiatic acid, as evidenced by increased cell viability and colony formation. Furthermore, knockdown of Akt mimicked the growth-suppressive activity of asiatic acid. Discussion and conclusionThese results provide first the evidence for the anticancer potential of asiatic acid in ovarian cancer cells, partially via inactivation of the PI3K/Akt/mTOR pathway. Asiatic acid may represent a potential therapeutic agent for ovarian cancer. [ABSTRACT FROM AUTHOR]

Abstract: The ketogenic diet (KD) is effective in the treatment of refractory epilepsy, yet the molecular mechanisms underlying its antiepileptic effects have not been determined. There is increasing evidence that neuronal cell death induced by seizures via mitochondrial pathway and seizures can lead to mitochondrial release of cytochrome c, and we have shown previously that translocation of Smac/DIABLO into the cytosol play a role in the brain damage in a model of limbic seizure. In the present study, we explored the neuroprotective effect of KD in C57BL/6 mice with seizures induced by kainic acid (KA). Status epilepticus triggered by intra-amygdaloid microinjection of KA lead to neuronal death in the selective ipsilateral CA3 subfield of the hippocampus and mitochondrial release of Smac/DIABLO and cytochrome c. We found that KD significantly decreased neuronal death in the ipsilateral CA3 at 24h after KA-induced seizures. Furthermore, KD reduced Smac/DIABLO and cytochrome c release from mitochondria, attenuated activation of casepase-9 and caspase-3 following seizures. These results demonstrate that the neuroprotective effect of KD against brain injury induced by limbic seizures, at least partially, is associated with inhibition of mitochondrial release of Smac/DIABLO and cytochrome c. [Copyright &y& Elsevier]

Abstract: Background: Primary graft dysfunction or nonfunction after liver transplantation, which is usually caused by ischemia/reperfusion injury (IRI), is a serious clinical problem. Although bone marrow mesenchymal stem cells (MSCs) have shown great potential in cell therapy for IRI in several organs, the mechanism(s) by which MSCs offer protection is unclear. Methods: In the present study, we injected MSCs systemically via the tail vein in the rat model of 70% hepatic IRI and measured the biochemical and pathologic alterations to evaluate the therapeutic effect of MSC transplantation. Concurrently, H2O2 was used in vitro to mimic oxidative injury and to induce apoptosis in the human normal liver cell line LO2 to evaluate the protective effects of mesenchymal stem cell conditioned medium (MSC-CM) on LO2 cells. Results: The systemic infusion of MSCs led to a significant prevention of liver enzyme release and an improvement in the histology of the acutely injured liver. In vitro assays demonstrated that MSC-CM promoted hepatocyte proliferation and had a direct inhibitory effect on hepatocyte apoptosis induced by H2O2. In addition, we demonstrated that the prevention of MEK/ERK pathway activation played a pivotal role in the protection. Conclusions: These data suggest that MSC may represent a potential therapeutic strategy to alleviate hepatic ischemia/reperfusion injuries after liver transplantation via inactivation of the MEK/ERK signaling pathway. [Copyright &y& Elsevier]