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Background: Nuclear factor-kB is highly activated in cardiovascular disorders. However, few articles have targeted at the role of nuclear factor-kB inhibitor in heart failure. Aims: To evaluate the effects of nuclear factor-kB inhibitor pyrrolidine dithiocarbamate on cardiocyte apoptosis and cardiac function in a rat heart failure model. Study Design: Animal experiment Methods: A stable and reproducible rat heart failure model (n=64) was prepared by injecting homologous microthrombotic particles into the left ventricle of Sprague--Dawley rats while obstructing the ascending aorta to produce coronary microembolization. Rats with heart failure were randomized into untreated (HFu) and pyrrolidine dithiocarbamate-treated (HFp) groups; the latter received an intraperitoneal injection of pyrrolidine dithiocarbamate (100 mg/kg/ day) 1 h prior to surgery as well as on postoperative days 1-7. The sham group comprised 32 Sprague--Dawley rats. Eight rats from each group were sacrificed on days 1, 3, 7, and 14 postoperatively. Masson's trichrome staining was used to determine the micro-fibrotic area to indicate the severity of myocardial loss. Terminal transferase uridine triphosphate nick end labeling staining was used to detect apoptotic cardiomyocytes. Echocardiography and hemodynamics were performed to evaluate left ventricular function. Results: Rats with heart failure exhibited pathological changes evidenced by patchy myocardial fibrosis, remarkably elevated severity of myocardial loss, and persistently reduced left ventricular function. At the end of the study, compared with the HFu group, myocardial infarct size was reduced by 28% (p=0.001), cardiocyte apoptosis was suppressed (7.17%±1.47% vs 2.83%±0.75%, p<0.001), cardiac function parameters such as left ventricular ejection fraction (80%±4% vs 61%±6%), left ventricular + dP/dt max (4828±289 vs 2918±76 mmHg.s-1), left ventricular - dP/dt max (4398±269 vs 2481±365 mmHg.s-1), and left ventricular systolic pressure (126±13 vs 100±10 mmHg) were significantly increased, and left ventricular end-diastolic pressure was reduced (18±2 vs 13±1 mmHg) (p<0.001, for all) in the HFu group. Conclusion: Our rat model can adequately mimic heart failure via coronary vessel embolization. Moreover, pyrrolidine dithiocarbamate treatment can reduce cardiocyte apoptosis and improve cardiac function, which may be beneficial for patients with heart failure secondary to myocardial infarction. [ABSTRACT FROM AUTHOR]

Inflammatory cytokines are able to induce vascular smooth muscle cells (VSMCs) to undergo apoptosis, causing atherosclerotic plaque rupture. Changes in the e×pression levels of conne×ins (C×s) have been demonstrated in VSMCs to be involved in the pathogenesis of atherosclerotic progression. The present study e×amined the effect of tumor necrosis factor-ɑ (TNF-ɑ) on C×43 e×pression levels and apoptosis in human VSMCs. Overe×pression of C×43 plasmids notably stimulated VSMC proliferation. TNF-ɑ directly inhibited C×43 e×pression levels in a dose- and time-dependent manner in VSMCs, however this was blocked by c-Jun N-terminal kinase inhibitor. TNF-ɑ also increased caspase-3 activity and apoptosis of VSMCs through the inhibition of C×43. These data suggested that TNF-ɑ induced the apoptosis of VMSCs and prompted the destabilization of atherosclerotic plaques by downregulating C×43. [ABSTRACT FROM AUTHOR]

Background: Caner-initiating cells (CICs or cancer stem cells) have been shown both experimentally and clinically to be resistant to radiation. The mechanism underlying radioresistance remains unclear. Methods: In the present study, we screened 51 genes which are potentially important in mediating radioresistance of breast CICs. Results: The expression of AKT1 and AKT2 at protein and mRNA levels was dramatically increased among the screened genes by 8 Gy radiation treatment in MCF-7 mammosphere cells (predominantly CD24/CD44 CICs), but not in the bulk population of MCF-7 cells (predominantly CD24/CD44). Using apoptosis and clonogenic survival assays, we found pharmacological inhibition of AKT with selective inhibitors of AKT sensitized MCF-7 mammosphere cells, but not MCF-7 monolayer cells to radiation. Conclusion: The present findings suggest that treatment with AKT inhibitors prior to ionizing radiation treatment may be a potential benefit to patients with breast cancer, in particular to eradiate breast CICs. [ABSTRACT FROM AUTHOR]

The expression of Ezrin-radixin-moesin-binding phosphoprotein-50 (EBP50) and the intragenic mutation of the ebp50 gene have been reported to correlate with human breast cancer development, but the exact impacts on breast cancer development and its molecular mechanism are not fully understood. In this study, we investigate the potential function of EBP50 through over-expression in the breast cancer cell line, MDA-MB-231, which has low EBP50 protein expression levels. The effects of EBP50 over-expression on cellular proliferation, anchorage-independent growth and apoptosis were examined. In addition, the activity of extracellular signal-regulated kinase (ERK) was also determined. Our results show that a decrease of cellular proliferation and attenuation of colony-forming ability were evident in MDA-MB-231 cells stably transfected with an EBP50 expressing plasmid (EBP-231) when compared with control cells. There was also a statistically significant increase in spontaneous apoptosis in EBP-231 cells accompanied by an attenuation in ERK activity. Altogether, our results suggest that restoring EBP50 expression could suppress breast cancer cell proliferation by promoting cell apoptosis and inhibiting ERK activity, and that EBP50 may be a target for development of diagnostics and therapeutics in breast cancer. [ABSTRACT FROM AUTHOR]

Hypericum ascyron L. (Great St. Johnswort), which belongs to the Hypericaceae family, has been used for the treatment of hematemesis, metrorrhagia, rheumatism, swelling, stomach ache, abscesses, dysentery and irregular menstruation for >2,000 years in China. The aim of the present study was to clarify the anticancer activity compounds from H. ascyron L. and the underlying molecular mechanism. Anticancer activity of H. ascyron L. extract was evaluated using an MTT assay. To confirm the anticancer mechanism of activity compounds, Hoechst 33258, Annexin V‑fluorescein isothiocyanate/propidium iodide, 2',7'‑dichlorodihydrofluorescein diacetate, rhodamine 123 staining and caspase‑3 activity analysis were performed. The results demonstrated that the anti‑proliferative action of the mixture of kaempferol 3‑O‑β‑(2"‑acetyl) galactopyranoside (K) and quercetin (Q) (molar ratio, 1:1) was significantly increased compared with either of these two compounds separately, and the active fraction of the H. ascyron L. extract |(HALE). HALE, indicating that the anti‑proliferative function of H. ascyron L. may be a synergic effect of K and Q. Furthermore, the inhibitory effect of KQ on the growth of HeLa cells was mediated by the induction of apoptosis. To the best of our knowledge, the present study is the first to identify that KQ exhibits significant anti‑proliferation activity on HeLa cells via the apoptotic pathway, and is also the first to evaluate the anticancer potential of H. ascyron L. The results of the present study may provide a rational base for the use of H. ascyron L. in the clinic, and shed light on the development of novel anticancer drugs. [ABSTRACT FROM AUTHOR]

Summary: Objective: To explore the role of miR‐181b in alterations of apoptosis and autophagy in the kainic acid (KA)‐induced epileptic juvenile rats via modulating TLR4 and P38/JNK signaling pathway. Methods: Dual‐luciferase reporter assay was performed to testify the targeting relationship between miR‐181b and TLR4. After intracerebroventricular injection (i.c.v.) of KA, rats were injected with miR‐181b agomir and TLR4 inhibitor (TAK‐242). The TLR‐4 activator lipopolysaccharide (LPS) was also administered into rats immediately after injection with miR‐181b agomir. Quantitative real‐time‐polymerase chain reaction (qRT‐PCR) was used for detections of miR‐181b and TLR4 expressions, hematoxylin‐eosin (HE) and Nissl staining for observation of the hippocampus morphological changes, and TUNEL staining for apoptosis analysis. Moreover, western blot was determined to detect TLR4 and P38/JNK pathway proteins, as well as autophagy‐ and apoptosis‐related proteins. Results: TLR4 was identified as a direct target of miR‐181b using Dual‐luciferase reporter assay. KA rats injected with miR‐181b agomir or TAK‐242 had improved learning and memory abilities, reduced seizure severity of Racine's scale, and lessened neuron injury. Additionally, miR‐181b agomir or TAK‐242 could significantly inhibit P38/JNK signaling, decrease LC3II/I, Beclin‐1, ATG5, ATG7, ATG12, Bax, and cleaved caspases‐3, but increase p62 and Bcl‐2 expression. No significances were found between KA group and KA + miR‐181b + LPS group. Conclusion: MiR‐181b could inhibit P38/JNK signaling pathway via targeting TLR4, thereby exerting protective roles in attenuating autophagy and apoptosis of KA‐induced epileptic juvenile rats. [ABSTRACT FROM AUTHOR]

Deletion of p53, most common genetic alteration, is observed in human tumors and reported to lead to improve in cell radioresistance. Heavy-ion irradiation (IR) could induce p53-/- cancer cells apoptosis. However, little is known regarding the molecular mechanism in this type of cell apoptosis. The present studies have focused on mechanisms state of signaling pathways as an activator of the cell fate decisions induced by heavy ion IR without p53. Carbon ion IR could induce up-regulation of E2F1 expression in cancer cells. This phenomenon was not observed in X-ray IR group. Up-regulation of E2F1 could cause a higher reduction in clonogenic survival, low level of cellular activity, G2/M phase arrest, promotion of apoptosis rate, up-regulation of phosphor-Rb, Bax, and cleaved-caspase 3 proteins expressions without p53. Changes of E2F1 expressions could partly alter radioresistance in cancer cells. The results were suggested that heavy ion IR could induce p53-/- cancer cells apoptosis via E2F1 signal pathway. Our study provides a scientific rationale for the clinical use of heavy ion as radiotherapy in patients with p53-deficient tumors, which are often resistant to radiotherapy. [ABSTRACT FROM AUTHOR]

Osteosarcoma is the most common aggressive sarcoma of the bone in children and adolescents. It is characterized by a high level of genetic instability and recurrent DNA deletions and amplifications. microRNAs (miRNAs) play a key role in cancer initiation, progression and metastasis; however, the potential role of miRNAs in osteosarcoma remains largely unknown. In the present study, miR-433 was shown to be overexpressed in osteosarcoma tissues compared with normal human osteoblasts. Transfection of miR-433 mimics into osteosarcoma cell lines significantly decreased apoptosis by targeting programmed cell death 4, a tumor suppressor that is involved in apoptosis. In contrast, inhibition of miR-433 enhanced apoptosis. Furthermore, in vivo miR-433 overexpression inhibited the apoptosis of tumor cells and increased tumor growth. The results of the present study suggested that miR-433 is a potential molecular target for osteosarcoma therapy. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that endothelial microparticles (EMPs), a marker of endothelial damage, are elevated in acute graft-versus-host disease (aGVHD), and that endothelial damage is implicated in the pathogenesis of aGVHD, but the mechanisms remain elusive. In this study, we detected the plasma EMP levels and endothelial damage in patients and mice with aGVHD in vivo and then examined the effects of EMPs derived from injured endothelial cells (ECs) on endothelial damage and the role of hedgehog- interacting protein (HHIP) carried by EMPs in these effects in vitro. Our results showed that EMPs were persistently increased in the early posttransplantation phase in patients and mice with aGVHD. Meanwhile, endothelial damage was continuous in aGVHD mice, but was temporary in non-aGVHD mice after transplantation. In vitro, EMPs induced endothelial damage, including increased EC apoptosis, enhanced reactive oxygen species, decreased nitric oxide production and impaired angiogenic activity. Enhanced expression of HHIP, an antagonist for the Sonic hedgehog (SHH) signaling pathway, was observed in patients and mice with aGVHD and EMPs from injured ECs. The endothelial damage induced by EMPs was reversed when the HHIP incorporated into EMPs was silenced with an HHIP small interfering RNA or inhibited with the SHH pathway agonist, Smoothened agonist. This work supports a feasible vicious cycle in which EMPs generated during endothelial injury, in turn, aggravate endothelial damage by carrying HHIP into target ECs, contributing to the continuously deteriorating endothelial damage in the development of aGVHD. EMPs harboring HHIP would represent a potential therapeutic target for aGVHD. [ABSTRACT FROM AUTHOR]

Hypericum ascyron L. has been used as a traditional medicine for the treatment of wounds, swelling, headache, nausea and abscesses in China for thousands of years. However, modern pharmacological studies are still necessary to provide a scientific basis to substantiate their traditional use. In this study, the mechanism underlying the antimicrobial effect of the antibacterial activity compounds from H. ascyron L. was investigated. Bioguided fractionation of the extract from H. ascyron L. afforded antibacterial activity fraction 8. The results of cup plate analysis and MTT assay showed that the MIC and MBC of fraction 8 is 5 mg/mL. Furthermore, using Annexin V-FITC/PI, TUNEL labeling and DNA gel electrophoresis, we found that cell death with apoptosis features similar to those in eucaryon could be induced in bacteria strains after exposure to the antibacterial activity compounds from H. ascyron L. at moderate concentration. In addition, we further found fraction 8 could disrupt the cell membrane potential indicate that fraction 8 exerts pro-apoptotic effects through a membrane-mediated apoptosis pathway. Finally, quercetin and kaempferol 3- O - β -(2″-acetyl)-galactopyranoside, were identified from fraction 8 by means of Mass spectrometry and Nuclear magnetic resonance. To our best knowledge, this study is the first to show that Kaempferol 3- O - β -(2″-acetyl)-galactopyranoside coupled with quercetin had significant antibacterial activity via apoptosis pathway, and it is also the first report that Kaempferol 3- O - β -(2″-acetyl)-galactopyranoside was found in clusiacea. Our data might provide a rational base for the use of H. ascyron L. in clinical, and throw light on the development of novel antibacterial drugs. [ABSTRACT FROM AUTHOR]

Bufalin is a traditional oriental medicine which is known to induce apoptosis in many tumor cells, and it is thus considered as a new anticancer therapeutic. By now, most of the studies of bufalin are in vitro, however in vivo evaluations of its therapeutic efficacy are less and are in great demand for its development toward anticancer drug. One of the problems probably hampering the development of bufalin is the lack of tumor selectivity, which may reduce the therapeutic effect as well as showing side effects. To overcome this drawback, in this study, we designed a tumor-targeted drug delivery system of bufalin based on enhanced permeability and retention (EPR) effect, by using biotinylated chitosan, resulting in bufalin encapsulating nanoparticles (Bu-BCS-NPs) with mean hydrodynamic size of 171.6 nm, as evidenced by dynamic light scattering and transmission electron microscope. Bu-BCS-NPs showed a relative slow and almost linear release of bufalin, and about 36.8% of bufalin was released in 24 h when dissolved in sodium phosphate buffer. Compared to native bufalin, Bu-BCS-NPs exhibited a stronger cytotoxicity against breast cancer MCF-7 cells (IC50 of 0.582 μg/ml vs 1.896 μg/ml of native bufalin). Similar results were also obtained in intracellular reactive oxygen species production, apoptosis induction, and decrease in mitochondria membrane potential. These results may contribute to the rapid intracellular uptake of nanoparticles, partly benefiting from the highly expressed biotin receptors in tumor cells. In vivo studies using MCF-7 tumor models in nude mice confirmed the remarkable therapeutic effect of Bu-BCS-NPs. These findings suggest the potential of Bu-BCS-NPs as an anticancer drug with tumor targeting property. [ABSTRACT FROM AUTHOR]

Background/Aims: Glutamine showed cytoprotective activ-ity in vitro on anoxia-reoxygenation injury via induction of heme oxygenase-1 (HO-1). We thus investigated its in vivo tissue-protective effect in a rat liver ischemia-reperfusion (l/R) model. Methods: Before the l/R procedure, animals were treated with glutamine. Liver injury was evaluated by serum liver enzymes, histological examination and apopto-sis detection bytransferase-mediated uridine nick end label-ing staining. Meanwhile, expression and activities of HO-1 were measured by Western blot and a biochemical method. Liver blood flow was measured by using a laser Doppler flowmeter, and oxidative injury was Investigated by the thio-barblturic acid-reactive substance (TBARS) assay. The inflam-matory cytokine monocyte chemotactic protein (MCP)-1 was quantified by ELISA. Results: l/R caused a large increase in levels of liver enzymes, remarkably Inducing the necrosis and apoptosis of liver tissue, which was markedly Inhibited by glutamine, during which HO-1 was upregulated signifi-cantly, and the HO-1 inhibitor zinc protoporphyrin nullified the effect of glutamine. Liver blood flow was greatly reduced after l/R; however, it was significantly improved by gluta-mine. Lipid peroxidation (TBARS) in liver tissue was largely induced which was significantly lowered by glutamine. Sim-ilar results were also observed for the production of MCP-1. Conclusion: Glutamine protected tissue against oxidative injury during rat hepatic l/R, by induction of HO-1 to fulfill antioxidative and antiapoptotic effects. [ABSTRACT FROM AUTHOR]