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BACKGROUND: Disturbance of mitochondrial fission and fusion (termed mitochondrial dynamics) is one of the leading causes of ischemia/reperfusion (I/R)-induced myocardial injury. Previous studies showed that mitochondrial aldehyde dehydrogenase 2 (ALDH2) conferred cardioprotective effect against myocardial I/R injury and suppressed I/R-induced excessive mitophagy in cardiomyocytes. However, whether ALDH2 participates in the regulation of mitochondrial dynamics during myocardial I/R injury remains unknown. METHODS: In the present study, we investigated the effect of ALDH2 on mitochondrial dynamics and the underlying mechanisms using the H9c2 cells exposed to hypoxia/reoxygenation (H/R) as an in vitro model of myocardial I/R injury. RESULTS: Cardiomyocyte apoptosis was significantly increased after oxygen-glucose deprivation and reoxygenation (OGD/R), and ALDH2 activation largely decreased the cardiomyocyte apoptosis. Additionally, we found that both ALDH2 activation and overexpression significantly inhibited the increased mitochondrial fission after OGD/R. Furthermore, we found that ALDH2 dominantly suppressed dynamin-related protein 1 (Drp1) phosphorylation (Ser616) and adenosine monophosphate-activated protein kinase (AMPK) phosphorylation (Thr172) but not interfered with the expression levels of mitochondrial shaping proteins. CONCLUSIONS: We demonstrate the protective effect of ALDH2 against cardiomyocyte H/R injury with a novel mechanism on mitochondrial fission/fusion. [ABSTRACT FROM AUTHOR]

Introduction: Eriodictyol is an important flavonoid and is commonly present across the plant kingdom. Flavonoids have been reported to show incredible pharmacological potential. However, the anticancer activity of the important flavonoid eriodictyol has not been well reported. In the present study we determined its anticancer potential against the human lung cancer cell line A549.Material and Methods: The initial cytotoxicity induced by eriodictyol was measured by MTT assay. Flow cytometry was used to study the effects of eriodictyol on apoptosis, cell cycle phase distribution and mitochondrial membrane potential loss. The comet assay was used to measure DNA damage induced by eriodictyol in cancer cells while the western blot assay indicated effects of the compound on Bax/Blc-2 and PI3K/AKT/m-TOR proteins.Results: The results showed that eriodictyol has an IC50 value of 50 μM against human lung cancer cells as compared to the IC50 of 95 µM against non-cancerous FR2 cells. The molecule exerted its anticancer activity through induction of apoptosis by regulating the Bcl-2/Bax signalling pathway. It caused cell cycle arrest of human lung cancer A549 cells at G2/M phase. Eriodictyol was also found to cause a reduction of the mitochondrial membrane potential in a dose-dependent manner. Additionally, eriodictyol effectively inhibited the mTOR/PI3K/Akt signalling pathway in a dose-dependent manner.Conclusions: Based on the above findings, we conclude that eriodictyol exerts its anticancer activity through induction of mitochondrial apoptosis and G2/M cell cycle arrest and inhibition of the TOR/PI3K/Akt cascade, indicating that it may have potential as a lead compound in the treatment of lung cancer, provided further in depth studies are done. [ABSTRACT FROM AUTHOR]

Regulation of mitochondrial metabolism is becoming an important target in inhibiting necrosis and apoptosis following secondary spinal cord injury, and physiological compounds that reduce mitochondrial dysfunction are regarded as efficient protective reagents following injury. It has been demonstrated that spermine, a polyamine composed of four primary amines, may be taken up by a mitochondria‑specific uniporter and may preserve mitochondrial bioenergetics, suggesting that it may be important in the pathophysiology of mitochondria. However, the protective mechanism has not yet been definitively clarified. In the present study, isolated spinal cord mitochondria were incubated with spermine to evaluate its physiological functions and Src kinase activities. The results revealed that spermine increased oxidative phosphorylation, attenuated mitochondrial swelling and maintained the membrane potential. An inhibitor of Src kinases, amino‑5-(4‑chlorophenyl)‑7‑(t‑butyl)pyrazolo[3,4‑d]pyrimidine (PP2), markedly reduced the effects of spermine. However, inhibition of tyrosine phosphatases by vanadate led to marginal increases in the effects of spermine. Therefore, the present study hypothesized that tyrosine phosphorylation sites are present in the subunits of respiratory chains and mitochondrial permeability transition pore proteins, which may be modified via phosphorylation and dephosphorylation. Furthermore, spermine may upregulate the phosphorylation of Src kinases, and PP2 and vanadate conversely regulate Src phosphorylation. The results of the present study suggest that spermine is a strategic regulator within mitochondria that may activate Src kinases in the spinal cord, and tyrosine phosphorylation signaling is a primary regulatory pathway of mitochondrial metabolism. [ABSTRACT FROM AUTHOR]

Reactive microglia are present in lesions of myelin-associated white matter disorders resulting in injuries to oligodendrocyte precursor cells (OPCs). Therefore, protection of OPCs from injury due to excessive activation of microglia is important in treating these diseases. Heat shock protein 60 (HSP60) has been demonstrated to be released extracellularly in the failing heart upon stress or injury. However, the role of HSP60 in the central nervous system and whether it participates in the toxic effects of microglia on OPCs remains unclear. The present study used the co-culture, cell death assays, binding assays, immunochemistry, western blot and ELISA. HSP60 was demonstrated to be released extracellularly by LPS-activated microglia and to bind to OPCs, triggering OPC apoptosis. When pretreated with toll-like receptor (TLR) 4 blocking antibody, the viability of OPCs increased, while the expression of nuclear factor κB (NFκB), caspase 3 and the release of proinflammatory cytokines triggered by HSP60 decreased. These results suggest that HSP60 released by microglia may mediate OPC apoptosis through binding to TLR4 on the surface of OPCs and subsequently activating the TLR4-NFκB signaling pathway. HSP60 may, therefore, serve as a potential target for treatment of myelin-associated neurodegenerative diseases that are accompanied by microglia activation. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect and underlying mechanism of Aceglutamide on motor dysfunction in rats after cerebral ischemia-reperfusion. Methods: Adult male Sprague-Dawley rats were subjected to 2 h transient middle cerebral artery occlusion (MCAO). Aceglutamide or vehicle was intraperitoneally given to rats at 24 h after reperfusion and lasted for 14 days. Subsequently functional recovery was assessed and number of tyrosine hydroxylase (TH)-positive neurons in substantia nigra (SN) was analyzed. Tumor necrosis factor receptor-associated factor 1(TRAF1), P-Akt and Bcl-2/Bax were determined in mesencephalic tissue byWestern blot method. PC12 cells and primary cultured mesencephalic neurons were employed to further investigate the mechanism of Aceglutamide. Results: Aceglutamide treatment improved behavioral functions, reduced the infarction volume, and elevated the number of TH-positive neurons in the SN. Moreover, Aceglutamide significantly attenuated neuronal apoptosis in the SN. Meanwhile Aceglutamide treatment significantly inhibited the expression of TRAF1 and up-regulated the expression of P-Akt and Bcl-2/Bax ratio both in vitro and in vivo. Conclusions: Aceglutamide ameliorated motor dysfunction and delayed neuronal death in the SN after ischemia, which involved the inhibition of pro-apoptotic factor TRAF1 and activation of Akt/Bcl-2 signaling pathway. These data provided experimental information for applying Aceglutamide to ischemic stroke treatment. [ABSTRACT FROM AUTHOR]

Background: We had previously shown that the bLZip domain-containing transcription factor, Zhangfei/CREBZF inhibits the growth and the unfolded protein response (UPR) in cells of the D-17 canine osteosarcoma (OS) line and that the effects of Zhangfei are mediated by it stabilizing the tumour suppressor protein p53. To determine if our observations with D-17 cells applied more universally to canine OS, we examined three other independently isolated canine OS cell lines--Abrams, McKinley and Gracie. Results: Like D-17, the three cell lines expressed p53 proteins that were capable of activating promoters with p53 response elements on their own, and synergistically with Zhangfei. Furthermore, as with D-17 cells, Zhangfei suppressed the growth and UPR-related transcripts in the OS cell lines. Zhangfei also induced the activation of osteocalcin expression, a marker of osteoblast differentiation and triggered programmed cell death. Conclusions: Osteosarcomas are common malignancies in large breeds of dogs. Although there has been dramatic progress in their treatment, these therapies often fail, leading to recurrence of the tumour and metastatic spread. Our results indicate that induction of the expression of Zhangfei in OS, where p53 is functional, may be an effective modality for the treatment of OS. [ABSTRACT FROM AUTHOR]

Smad7 is an intracellular inhibitory protein that antagonizes the signaling of TGF-β family members. Deletion of Smad7 in the mouse leads to an abnormality in heart development. However, whether Smad7 has a functional role in the development of other organs has been elusive. Here we present evidence that Smad7 imparts a role to eye development in the mouse. Smad7 is expressed in both the lens and retina in the developing embryonic eye. Depletion of Smad7 caused various degrees of coloboma and microphthalmia with alterations in cell apoptosis and proliferation in eyes. Smad7 was implicated in lens differentiation but was not required for the induction of the lens placode. The development of the periocular mesenchyme was retarded with the down-regulation of Bmp7 and Pitx2 in mutant mice. Retinal spatial patterning was affected by Smad7 deletion and was accompanied by altered bone morphogenetic protein (BMP) signaling. At late gestation stages, TGF-β signaling was up-regulated in the differentiating retina. Smad7 mutant mice displayed an expanded optic disc with increasing of sonic hedgehog (SHH) signaling. Furthermore, loss of Smad7 led to a temporal change in retinal neurogenesis. In conclusion, our study suggests that Smad7 is essential for eye development. In addition, our data indicate that alterations in the signaling of BMP, TGF-β and SHH likely underlie the defects in eye development caused by Smad7 deletion. [ABSTRACT FROM AUTHOR]

The therapeutic effect of stroke is hampered by the lack of neuroprotective drugs against ischemic insults beyond the acute phase. Carnitine plays important roles in mitochondrial metabolism and in modulating the ratio of coenzyme A (CoA)/acyl-CoA. Here, we investigate the neuroprotective effects of L-carnitine (LC) and Acetyl-L-carnitine (ALC) pre-treatment on ischemic insults under the same experimental conditions. We used a transient middle cerebral artery occlusion (MCAO) model to evaluate the protective roles of LC and ALC in acute focal cerebral ischemia in vivo and to understand the possible mechanisms using model of PC12 cell cultures in vitro. Results showed that ALC, but not LC, decreased infarction size in SD rats after MCAO in vivo. However, both LC and ALC pretreatment reduced oxygen-glucose deprivation (OGD)-induced cell injury and decreased OGD-induced cell apoptosis and death in vitro; at the same time, both of them increased the activities of super oxide dismutase (SOD) and ATPase, and decreased the concentration of malondialdehyde (MDA) in vitro. Thus, our findings suggested that LC and ALC pre-treatment are highly effective in the prevention of neuronal cell against ischemic injury in vitro, however, only ALC has the protective effect on neuronal cell injury after ischemia in vivo. [ABSTRACT FROM AUTHOR]

The toxicity of formaldehyde (HCHO) has been attributed to its ability to form adducts with DNA and proteins. Triphlorethol-A, derived from Ecklonia cava, was reported to exert a cytoprotective effect against oxidative stress damage via an antioxidant mechanism. The aim of this study was to examine the mechanisms underlying the triphlorethol-A ability to protect Chinese hamster lung fibroblast (V79-4) cells against HCHO-induced damage. Triphlorethol-A significantly decreased the HCHO-induced intracellular reactive oxygen species (ROS) production. Triphlorethol-A prevented increased cell damage induced by HCHO via inhibition of mitochondria-mediated caspase-dependent apoptosis pathway. Triphlorethol-A diminished HCHO-induced mitochondrial dysfunction, including loss of mitochondrial membrane action potential (Δψ) and adenosine triphosphate (ATP) depletion. Furthermore, the anti-apoptotic effect of triphlorethol-A was exerted through inhibition of c-Jun NH2-terminal kinase (JNK), which was enhanced by HCHO. Our data indicate that triphlorethol-A exerts a cytoprotective effect in V79-4 cells against HCHO-induced oxidative stress by inhibiting the mitochondria-mediated caspase-dependent apoptotic pathway. [ABSTRACT FROM AUTHOR]

Upon receiving an apoptotic stimulus, the mature mitochondrial protein second mitochondria-derived activator of caspases (Smac)/direct IAP-binding protein with low PI (DIABLO), which could be released from mitochondria into the cytosol together with cytochrome C, specifically binds to inhibitor of apoptosis proteins (IAPs) and relieves the inhibitory effect of caspase, thus promotes cell death. Some artificial small molecules (called Smac mimetics) can mimic the N-terminal four residues Ala1-Val2-Pro3-Ile4 (AVPI) sequence of mitochondrial protein Smac, and competitively bind to X-linked inhibitor of apoptosis protein baculoviral IAP repeats (XIAP-BIR3) domain with caspase-9, which leads to the removal of the inhibition of caspase-9 by XIAP and induce apoptosis. To gain an insight into the nature of XIAP-BIR3 domain recognizing Smac mimetics, we used docking and molecular dynamics simulations methods to study four representative Smac mimetics. The docking results show that the orientations of these backbones of ligands are identical with that of AVPI in the binding pocket. Each ligand corresponds to two competitive conformations, which are called extended and bended conformations. The results of molecular dynamics simulations show that the extended conformation is more stable, and the calculations of energy decomposition reveal that the residue Thr308 makes the strongest interaction with XIAP-BIR3. In addition, Asp309, Glu314, and Trp323 are indispensable for XIAP-BIR3 recognizing and binding Smac mimetics. [ABSTRACT FROM AUTHOR]

Background: Hypoxia is associated with abnormal cell apoptosis in trophoblast cells, which causes fetal growth restriction and related placental pathologies. Few effective methods for the prevention and treatment of placenta-related diseases exist. Natural products and functional foods have always been a rich source of potential anti-apoptotic drugs. Nobiletin (NOB), a hexamethoxyflavonoid derived from the citrus pomace, shows an anti-apoptotic activity, which is a non-toxic constituent of dietary phytochemicals approved by the Food and Drug Administration. However, their effects on hypoxia-induced human trophoblast cells have not been fully studied. Objective: The aim of this study was to investigate the protective effects of NOB on hypoxia-induced apoptosis of human trophoblast JEG-3 and BeWo cells, and their underlying mechanisms. Design: First, the protective effect of NOB on hypoxia-induced apoptosis of JEG-3 and BeWo cells was studied. Cell viability and membrane integrity were determined by CCK-8 assay and lactate dehydrogenase activity, respectively. Real Time Quantitative PCR (RT-qPCR) and Western blot analysis were used to detect the mRNA and protein levels of HIF1α. Propidium iodide (PI)-labeled flow cytometry was used to detect cell cycle distribution. Cell apoptosis was detected by flow cytometry with Annexin V-FITC and PI double staining, and the expression of apoptosis marker protein cl-PARP was detected by Western blot analysis. Then, the molecular mechanism of NOB against apoptosis was investigated. Computer molecular docking and dynamics were used to simulate the interaction between NOB and p53 protein, and this interaction was verified in vitro by Ultraviolet and visible spectrum (UV-visible spectroscopy), fluorescence spectroscopy and circular dichroism. Furthermore, the changes in the expression of p53 signaling pathway genes and proteins were detected by RT-qPCR and Western blot analysis, respectively. Results: Hypoxia treatment resulted in a decreased cell viability and cell membrane integrity in JEG-3 and BeWo cell lines, and an increased expression of HIF1α, cell cycle arrest in the G1 phase, and massive cell apoptosis, which were alleviated after NOB treatment. Molecular docking and dynamics simulations found that NOB spontaneously bonded to human p53 protein, leading to the change of protein conformation. The intermolecular interaction between NOB and human p53 protein was further confirmed by UV-visible spectroscopy, fluorescence spectroscopy and circular dichroism. After the treatment of 100 μM NOB, a down-regulation of mRNA and protein levels of p53 and p21 and an up-regulation of BCL2/BAX mRNA and protein ratio were observed in JEG-3 cells; however, there was also a down-regulation of mRNA and protein levels observed for p53 and p21 in BeWo cells after the treatment of NOB. The BCL2/BAX ratio of BeWo cells did not change after the treatment of 100 µM NOB. Conclusion: NOB attenuated hypoxia-induced apoptosis in JEG-3 and BeWo cell lines and might be a potential functional ingredient to prevent pregnancy-related diseases caused by hypoxia-induced apoptosis. These findings would also suggest the exploration and utilization of citrus resources, and the development of citrus industry. [ABSTRACT FROM AUTHOR]

Atherosclerosis is characterized by localized lesions distributed in the arterial tree due to the shear stress produced by blood flow. Endothelial cells are directly affected by alterations in blood flow. Dysfunction and injury to endothelial cells has been hypothesized to initiate the pathological processes of atherosclerosis. The present study aimed to investigate the mechanism of shear stress‑induced endothelial cellular apoptosis. Shear stress was generated using an artificial device to mimic the impact of disturbed blood flow on cultured human aortic endothelial cells (HAECs). Cellular apoptosis was assessed using a terminal deoxynucleotidyl transferase dUTP nick end labeling assay; an ELISA assay was used to detect the produced interleukin (IL)‑1β; specific small interfering (si)RNA was used to knockdown the expression of interleukin‑1 receptor‑associated kinase 2 (IRAK2) in HAECs and the expression levels of 78 kDa glucose‑regulated protein, DNA damage‑inducible transcript 3 protein (CHOP), IRAK2 and IL‑1β were evaluated using western blotting. The results of the present study demonstrated that artificial shear stress induced endoplasmic reticulum (ER) stress, IL‑1β production and apoptosis in HAECs in a time‑dependent manner. The inhibition of ER stress, and treatment with interleukin‑1 receptor antagonist protein and siRNA against IRAK2 attenuated shear stress‑induced CHOP signaling‑mediated cellular apoptosis. Therefore, overproduction of IL‑1β exacerbated shear stress‑induced ER stress‑mediated apoptosis via the IRAK2/CHOP signaling pathway in endothelial cells. [ABSTRACT FROM AUTHOR]

Introduction: The function of the C6orf120 gene, which encodes an N-glycosylated protein, remains unknown. The study was performed to characterize the utility of the C6orf120 gene in carbon tetrachloride-induced acute liver injury and to elucidate the potential underlying mechanisms by establishing a C6orf120 gene-knockout (C6orf120–/–) rat model. Material and methods: C6orf120–/– and wild-type (WT) rats were intraperitoneally administered with CCl4 (1 : 1 v/v in olive oil, 2 µl/g). Rats were sacrificed 24 h after CCl4 administration. Liver tissues were collected for H&E, IHC, qRT-PCR, and Western blot analysis. Results: C6orf120 gene deficiency may be vulnerable to CCl4 -induced acute liver injury in rats as indicated by the high levels of alanine aminotransferase (WT: 388.7 ±55.96 vs. C6orf120–/–: 915.9 ±118.8, p < 0.001) and greater degree of pathological damage. Quantitative reverse transcription polymerase chain reaction showed that the mRNA levels of inflammation-associated cytokines, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, in liver tissues were increased in C6orf120–/– rats compared with those in WT rats. Moreover, western blot showed that the protein expression of cytokines nucleotide-binding oligomerization domain leucine rich repeat and pyrin domain containing 3 (NLRP3), caspase-1, IL-1β, nuclear factor-kB, c-Jun N-terminal kinases, and Bax were increased in C6orf120–/– rats compared with those in WT rats. Conclusions: C6orf120–/– rats were susceptible to CCl4 -induced liver injury, which may be related to NLRP3 inflammasome and JNK signaling pathway activation. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a degenerative joint disease that affects millions of people. Currently, there is no effective drug treatment for it. The purpose of this study is to investigate the chondroprotective effects of Murraya exotica (L.) on OA. The rat OA models were duplicated to prepare for separating OA chondrocytes, synovial fluid (SF), and serum containing M. exotica (50mg/kg, 100mg/kg, and 200 mg/kg), M. exotica showed the activity of decreasing the contents of TNF-β and IL-1β in SF and the chondrocyte apoptosis in a dose-dependent manner. To investigate the probable mechanism, quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used to determine gene expression and protein profiles, respectively. The results reveal that M. exotica can downregulate mRNA and protein expressions of β-catenin and COX-2 and reporter activity significantly. Conclusively, M. exotica exhibits antiapoptotic chondroprotective activity probably through inhibiting β-catenin signaling. [ABSTRACT FROM AUTHOR]

Recently, we demonstrated that myricetin exhibits cytoprotective effects against H2O2-induced cell damage via its antioxidant properties. In the present study, myricetin was found to inhibit H2O2-induced apoptosis in Chinese hamster lung fibroblast (V79-4) cells, as shown by decreased apoptotic bodies, nuclear fragmentation, sub-G1 cell population, and disruption of mitochondrial membrane potential (ΔΨm), which are increased in H2O2-treated cells. Western blot data showed that in H2O2-treated cells, myricetin increased the level of Bcl-2, which is an anti-apoptotic factor, and decreased the levels of Bax, active caspase-9 and -3, which are pro-apoptotic factors. And myricetin inhibited release of cytochrome c from mitochondria to cytosol in H2O2-treated cells. Myricetin-induced survival correlated with Akt activity, and the rescue of cells by myricetin treatment against H2O2-induced apoptosis was inhibited by the specific PI3K (phosphoinositol-3-kinase) inhibitor. Myricetin-mediated survival also inhibited the activation of p38 mitogen activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK), which are members of MAPK. Our studies suggest that myricetin prevents oxidative stress-induced apoptosis via regulation of PI3K/Akt and MAPK signaling pathways. [ABSTRACT FROM AUTHOR]

The protective effect of Castanopsis cuspidate var. sieboldii was examined on H2O2-induced cell damage. The ethanol extract of Castanopsis cuspidate was found to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and reduce intracellular reactive oxygen species (ROS) generation, and thus prevent lipid peroxidation and cellular DNA damage induced by H2O2. As a result, Castanopsis extract reduced H2O2-induced cell death of V79-4 cells via inhibition of apoptosis. Castanopsis extract was also found to increase catalase activity and its protein expression. Further molecular mechanistic studies revealed that Castanopsis extract enhanced phosphorylation of extracellular signal regulated kinase (ERK) and activity of nuclear factor kappa B (NF-κB). Taken together, the results suggest that Castanopsis extract protects V79-4 cells against oxidative damage by enhancing catalase activity and modulating the ERK and NF-κB signal pathway. [ABSTRACT FROM AUTHOR]

The high mortality and disability of diabetic nonhealing skin ulcers create an urgent need for the development of more efficacious strategies targeting diabetic wound healing. In the current study, using human clinical specimens, we show that perilesional skin tissues from patients with diabetes are under more severe oxidative stress and display higher activation of the nuclear factor-E2-related factor 2 (NRF2)-mediated antioxidant response than perilesional skin tissues from normoglycemic patients. In a streptozotocin-induced diabetes mouse model, Nrf2(-/-) mice have delayed wound closure rates compared with Nrf2(+/+) mice, which is, at least partially, due to greater oxidative DNA damage, low transforming growth factor-β1 (TGF-β1) and high matrix metalloproteinase 9 (MMP9) expression, and increased apoptosis. More importantly, pharmacological activation of the NRF2 pathway significantly improves diabetic wound healing. In vitro experiments in human immortalized keratinocyte cells confirm that NRF2 contributes to wound healing by alleviating oxidative stress, increasing proliferation and migration, decreasing apoptosis, and increasing the expression of TGF-β1 and lowering MMP9 under high-glucose conditions. This study indicates an essential role for NRF2 in diabetic wound healing and the therapeutic benefits of activating NRF2 in this disease, laying the foundation for future clinical trials using NRF2 activators in treating diabetic skin ulcers. [ABSTRACT FROM AUTHOR]

Vinexin-β is one of the adaptor proteins that are primarily involved in signal transduction and cytoskeletal organization under various pathological conditions, including cardiac hypertrophy. However, the role of Vinexin-β in myocardial infarction (MI) remains unknown. In this study, dramatically up-regulated Vinexin-β expression was observed in both ischaemic human hearts and infarcted animal hearts. To explore the potential involvement of Vinexin-β in MI further, we induced MI injury in global Vinexin-β-knockout mice and wild-type (WT) controls as well as in mice with cardiac-specific over-expression of the human Vinexin-β gene-transgenic (TG) and -non-transgenic (NTG) littermates. Compared with that observed in WT controls, Vinexin-β deficiency significantly decreased MI-induced infarct size, concomitant with an improved cardiac function, leading to an increase in the survival rate. The myocardial apoptosis in the border zone was dramatically reduced by Vinexin-β deficiency, resulting from the altered expression of apoptotic factors. Furthermore, Vinexin-β depletion mitigated the inflammatory response, as evidenced by reduced inflammatory cell infiltration, decreased expression of cytokines and the inactivation of NF-κB (nuclear factor κB) signalling. In contrast, Vinexin-β-TG mice were much more susceptible to MI injury compared with NTG controls. Further mechanism analyses suggested that Vinexin-β exerted detrimental effects largely dependent on blocking AKT signalling. The effects and mechanisms of Vinexin-β on MI observed in vivo were further confirmed by our in vitro assays. When collected, these data demonstrate for the first time that Vinexin-β increases MI-induced mortality and worsens cardiac dysfunction through aggravation of myocardial apoptosis and inflammatory response. [ABSTRACT FROM AUTHOR]

Background: miRNAs are single-stranded, small RNA molecules with a length of 18-25 nucleotides. They bind to the 3' untranslated regions of mRNA transcripts to reduce the translation of these transcripts or to cause their degradation. The roles of these molecules differ in biological processes, such as cell differentiation, proliferation, apoptosis and tumor genesis. miRNA-33 is encoded by the gene introns of proteins that bind sterol-regulatory elements. This molecule cooperates with these proteins to control cholesterol homeostasis, fatty acid levels and the genes that are related to the expression of fat metabolism. The examination of miR-33 expression and its target genes can promote the in-depth study of the miRNA regulation mechanism in the formation process of goose fatty liver and can lay a foundation for research into human fatty liver. Methodology/principal findings: (1) Through real-time fluorescent quantitative polymerase chain reaction (TaqMan MicroRNA Assay), we detected the expression of miR-33 during the feeding of Landes geese. The expression level of miR-33 increases significantly in the liver after 19 days in comparison with the control group; (2) By using the bioinformatics software programs TargetScan, miRDB and miRCosm to predict the target genes of miR-33 according to laboratory prophase transcriptome results and references, we screen nine target genes: adenosine triphosphate binding cassette transporters A1, adenosine triphosphate binding cassette transporters G1, Neimann Pick C, carnitine O-octanoyltransferase (CROT), cyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase, beta subunit (HADHB), AMP-activated protein kinase, alpha subunit 1 (AMPKα1), insulin receptor substrate 2, glutamic pyruvate transaminase and adipose differentiation-related protein. The dual luciferase reporter gene system in the CHO cell line verifies that CROT, HADHB and NPC1 are the target genes of miR-33 in geese. The inhibition rate of CROT is highest and reaches 70%; (3) The seed sequence (5' 2-8 bases) is the acting site of miR-33. The two predicted target sites of CROT are the target sites of miR-33. Moreover, the predicted target site of HADHB and NPC1 is the target site of miR-33. Conclusions/significance: (1) After 19 days of overfeeding, the expression level of miR-33 increases significantly in the livers of geese; (2) CROT, HADHB and NPC1 are the target genes of miR-33 in geese. These genes determine the combined target site. [ABSTRACT FROM AUTHOR]

Dickkopf-3 (DKK3) is a secreted glycoprotein of the Dickkopf family (DKK1–4) that modulates Wnt signalling. DKK3 has been reported to regulate cell development, proliferation, apoptosis, and immune response. However, the functional role of DKK3 in cardiac remodelling after myocardial infarction (MI) has not yet been elucidated. This study aimed to explore the functional significance of DKK3 in the regulation of post-MI remodelling and its underlying mechanisms. MI was induced by surgical left anterior descending coronary artery ligation in transgenic mice expressing cardiac-specific DKK3 and DKK3 knockout (KO) mice as well as their non-transgenic and DKK3+/+ littermates. Our results demonstrated that after MI, mice with DKK3 deficiency had increased mortality, greater infarct size, and exacerbated left ventricular (LV) dysfunction. Significantly, at 1 week post-MI, the hearts of DKK3-KO mice exhibited increased apoptosis, inflammation, and LV remodelling compared with the hearts of their DKK3+/+ littermates. Conversely, DKK3 overexpression led to the opposite phenotype after infarction. Similar results were observed in cultured neonatal rat cardiomyocytes exposed to hypoxia in vitro. Mechanistically, DKK3 promotes cardioprotection by interrupting the ASK1–JNK/p38 signalling cascades. In conclusion, our results indicate that DKK3 protects against the development of MI-induced cardiac remodelling via negative regulation of the ASK1–JNK/p38 signalling pathway. Thus, our study suggests that DKK3 may represent a potential therapeutic target for the treatment of heart failure after MI. [ABSTRACT FROM AUTHOR]

Background Lung cancer, especially non-small cell lung cancer, is a leading cause of malignant tumor death worldwide. Understanding the mechanisms employed by the main regulators, such as microRNAs (miRNAs) and transcription factors (TFs), still remains elusive. The patterns of their cooperation and biological functions in the synergistic regulatory network have rarely been studied. Results Here, we describe the first miRNA-TF synergistic regulation network in human lung cancer. We identified important regulators (MYC, NFKB1, miR-590, and miR-570) and significant miRNA-TF synergistic regulatory motifs by random simulations. The two most significant motifs were the co-regulation of miRNAs and TFs, and TF-mediated cascade regulation. We also developed an algorithm to uncover the biological functions of the human lung cancer miRNA-TF synergistic regulatory network (regulation of apoptosis, cellular protein metabolic process, and cell cycle), and the specific functions of each miRNA-TF synergistic subnetwork. We found that the miR-17 family exerted important effects in the regulation of non-small cell lung cancer, such as in proliferation and cell cycle regulation by targeting the retinoblastoma protein (RB1) and forming a feed forward loop with the E2F1 TF. We proposed a model for the miR-17 family, E2F1, and RB1 to demonstrate their potential roles in the occurrence and development of non-small cell lung cancer. Conclusions This work will provide a framework for constructing miRNA-TF synergistic regulatory networks, function analysis in diseases, and identification of the main regulators and regulatory motifs, which will be useful for understanding the putative regulatory motifs involving miRNAs and TFs, and for predicting new targets for cancer studies. [ABSTRACT FROM AUTHOR]

Purpose: 3,3'-Diindolylmethane (DIM) is a natural component of cruciferous plants. It has strong antioxidant and anti- angiogenic effects and promotes the apoptosis of a variety of tumor cells. However, little is known about the critical role of DIM on cardiac hypertrophy. In the present study, we investigated the effects of DIM on cardiac hypertrophy. Methods: Multiple molecular techniques such as Western blot analysis, real-time PCR to determine RNA expression levels of hypertrophic, fibrotic and oxidative stress markers, and histological analysis including H&E for histopathology, PSR for collagen deposition, WGA for myocyte cross-sectional area, and immunohistochemical staining for protein expression were used. Results: In pre-treatment and reverse experiments, C57/BL6 mouse chow containing 0.05% DIM (dose 100 mg/kg/d DIM) was administered one week prior to surgery or one week after surgery, respectively, and continued for 8 weeks after surgery. In both experiments, DIM reduced to cardiac hypertrophy and fibrosis induced by aortic banding through the activation of 5'-adenosine monophosphate-activated protein kinase-α2 (AMPKα2) and inhibition of mammalian target of the rapamycin (mTOR) signaling pathway. Furthermore, DIM protected against cardiac oxidative stress by regulating expression of estrogen-related receptor-alpha (ERRα) and NRF2 etc. The cardioprotective effects of DIM were ablated in mice lacking functional AMPKα2. Conclusion: DIM significantly improves left ventricular function via the activation of AMPKα2 in a murine model of cardiac hypertrophy. [ABSTRACT FROM AUTHOR]

The inducible IkB kinase (IKKi/IKKε) is a recently described serine-threonine IKK-related kinase. Previous studies have reported the role of IKKi in infectious diseases and cancer. However, its role in the cardiac response to pressure overload remains elusive. In this study, we investigated the effects of IKKi deficiency on the development of pathological cardiac hypertrophy using in vitro and in vivo models. First, we developed mouse models of pressure overload cardiac hypertrophy induced by pressure overload using aortic banding (AB). Four weeks after AB, cardiac function was then assessed through echocardiographic and hemodynamic measurements. Western blotting, real-time PCR and histological analyses were used to assess the pathological and molecular mechanisms. We observed that IKKi-deficient mice showed significantly enhanced cardiac hypertrophy, cardiac dysfunction, apoptosis and fibrosis compared with WT mice. Furthermore, we recently revealed that the IKKi-deficient mice spontaneously develop cardiac hypertrophy. Moreover, in vivo experiments showed that IKKi deficiency-induced cardiac hypertrophy was associated with the activation of the AKT and NF-κB signaling pathway in response to AB. In cultured cells, IKKi overexpression suppressed the activation of this pathway. In conclusion, we demonstrate that IKKi deficiency exacerbates cardiac hypertrophy by regulating the AKT and NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

A 14-residue phosphatidylserine (PS)-binding peptide FNFRLKAGQKIRFG (PSBP-0) was scanned with Ala. In addition, a radiometal chelator (SAAC) was introduced at selected sites of the lead peptides. Substitution of the Gln6residue in PSBP-0 with Ala resulted in a significant increase in binding affinity to PS as determined by surface plasmon resonance sensorgrams. The binding affinity of the resulting peptide FNFRLKAGAKIRFG (PSBP-6, molecular mass = 1623 Da) to PS (Kd∼ 100 nM) increased 10-fold as compared to PSBP-0 (Kd∼ 1.38 μM). Introduction of SAAC-Re to the N terminus of PSBP-6 further increased the binding affinity of the resulting peptide SAAC(Re)-PSBP-6 (Kd∼ 26 nM). SAAC(Re)-PSBP-6 shows specific binding to apoptotic cells in cell-based assays. Biodistribution studies showed significantly higher uptake of SAAC(99 mTc)-PSBP-6 in B16/F10 melanoma treated with poly(l-glutamic acid)-paclitaxel than untreated tumors (4.06 ± 0.55% ID/g vs 1.61 ± 0.33% ID/g, P= 0.00011). SAAC(99 mTc)-PSBP-6 is a promising probe for noninvasive imaging of apoptotic cells. [ABSTRACT FROM AUTHOR]

The N-myc downstream-regulated gene 2 (NDRG2) is involved in cell differentiation and apoptosis, but its function in the pancreas remains to be established. Herein we examine the expression and function of NDRG2 in the endocrine pancreas. NDRG2 immunoreactivity was localized mainly in the cytoplasm of pancreatic β cells. When β-TC3 cells were exposed chronically to high levels of free fatty acid (FFA), cell viability was impaired, and Akt and NDRG2 phosphorylation were reduced. NDRG2 is a potential substrate of protein kinase Akt. Overexpression of constitutively active Akt enhanced NDRG2 phosphorylation and abolished the apoptosis induced by FFA in β-TC3 cells, whereas NDRG2 knock-down attenuated Akt-mediated protection of β cells against fatty acid-triggered apoptosis. Collectively, these data indicate that NDRG2 acts as a key molecule in pancreatic β cells and is involved in the Akt-mediated protection of β cells against lipotoxicity. [ABSTRACT FROM AUTHOR]