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The importance of anti-apoptosis in mammalian cell culture has been widely recognized. We reported previously that expression of Bombyx mori 30 K genes in Chinese hamster ovary (CHO) cells increases recombinant protein production by inhibiting apoptosis and enhancing specific productivity. However, previous studies have shown expression of the anti-apoptotic 30Kc6 protein as inclusion bodies in Escherichia coli . 30Kc19 protein, another silkworm hemolymph protein, has cell-penetrating and recombinant protein productivity-improving properties, and we found that it improves soluble expression of its partner. In this study, we fused 30Kc6 with 30Kc19 as an expression partner to express a soluble fused protein and to deliver the protein to cells. Supplementing the recombinant 30Kc19-30Kc6 fusion protein in cell culture medium increased viability, effectively penetrated the cells, and inhibited CHO cell apoptosis by 68%. Moreover, the mitochondrial membrane potential and ATP generation also increased by 50% and 33%, respectively. Erythropoietin (EPO) productivity increased by > 30% because of the anti-apoptotic effect and increased specific productivity. These results demonstrate the potential use of this fusion protein as a supplement in mammalian cell culture during production of biopharmaceutical proteins. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Huang-Lian-Jie-Du-Tang (HLJDT) is a classical heat-clearing and detoxicating formula of traditional Chinese medicine that is widely used to treat stroke. The present study was designed to investigate the effects of HLJDT preconditioning on neurons under oxygen and glucose deprivation (OGD) and rats subjected to middle cerebral artery occlusion (MCAO). Materials and methods: A stroke model of rats was obtained through MCAO. Following HLJDT preconditioning, the cerebral infarction volume, cerebral water content, and neurological deficient score were determined. Cerebral cortical neurons cultured in vitro were preconditioned with HLJDT and then subjected to OGD treatment. The release of lactate dehydrogenase (LDH) from neurons was detected. The levels of hypoxia-inducible factor-1α (HIF-1α) and PI3K/Akt signaling were analyzed by western blotting, and the levels of erythropoietin (EPO) and vascular endothelial growth factor (VEGF) in the supernatant of the neurons and the plasma of MCAO rats were measured through a radioimmunological assay. The apoptosis and proliferation of neurons were analyzed by immunohistochemistry. Results: HLJDT preconditioning significantly reduced the cerebral infarction volume and cerebral water content and ameliorated the neurological deficient score of MCAO rats. In addition, HLJDT preconditioning protected neurons against OGD. Increased HIF-1α, EPO, and VEGF levels and the activation of PI3K/Akt signaling were observed as a result of HLJDT preconditioning. Furthermore, HLJDT preconditioning was found to inhibit ischemia-induced neuron apoptosis and to promote neuron proliferation under conditions of ischemia/reperfusion. Conclusion: Both rats and neurons subjected to HLJDT preconditioning were able to resist ischemia/reperfusion or hypoxia injury through the inhibition of apoptosis and the enhancement of proliferation, and these effects were primarily dependent on the activation of the PI3K/Akt signaling pathway and HIF-1α. [Copyright &y& Elsevier]

Abstract: JAK2 V617F mutant, a gene responsible for human myeloproliferative neoplasms (MPNs), causes not only cellular transformation but also resistance to various anti-cancer drugs. We previously reported that pyrrolidinium fullerene markedly induced the apoptosis of JAK2 V617F mutant-induced transformed cells through the reduction of apoptosis signal-regulating kinase 1 (ASK1), following inhibition of the c-Jun N-terminal kinase (JNK) pathway. In the current study, we found that the replacement of the 2-hydrogen atom ( H) or N-methyl group ( CH3) by the butyl group ( C4C9) caused the more than 3-fold potent cytotoxic effects on cells transformed by the JAK2 V617F mutant. Strikingly, these chemical modification of pyrrolidinium fullerene resulted in more marked reduction of ASK1 protein and a more potent inhibitory effect on the JNK signaling cascade. On the other hand, when modified with a longer alkyl group, the derivatives lacked their cytotoxicity. These observations clearly indicate that the modification of pyrrolidinium fullerene with a suitable length of alkyl group such as butyl group enhances its apoptotic effect through inhibition of the ASK1-MKK4/7-JNK pathway. [Copyright &y& Elsevier]

Objectives: The goal of this study was to define the role of FMS-like tyrosine kinase 3 (FLT3) in the heart. Background: FLT3 is a prominent target of receptor tyrosine kinase inhibitors (TKIs) used for anticancer therapy. TKIs can cause cardiomyopathy but understanding of the mechanisms is incomplete, partly because the roles of specific TKI target receptors in the heart are still obscure. Methods: Myocardial infarction was induced in mice by permanent ligation of the left anterior descending coronary artery followed by intramyocardial injection of FLT3 ligand (FL) or vehicle into the infarct border zone. Cardiac morphology and function were assessed by echocardiography and histological analysis 1 week after infarction. In addition, FLT3 expression and regulation, as well as molecular mechanisms of FLT3 action, were examined in cardiomyocytes in vitro. Results: The intramyocardial injection of FL into the infarct border zone decreased infarct size and ameliorated post-myocardial infarction remodeling and function in mice. This beneficial effect was associated with reduced apoptosis, including myocytes in the infarct border zone. Cardiomyocytes expressed functional FLT3, and FLT3 messenger ribonucleic acid and protein were up-regulated under oxidative stress, identifying cardiomyocytes as FL target cells. FLT3 activation with FL protected cardiomyocytes from oxidative stress–induced apoptosis via an Akt-dependent mechanism involving Bcl-2 family protein regulation and inhibition of the mitochondrial death pathway. Conclusions: FLT3 is a cytoprotective system in the heart and a potential therapeutic target in ischemic cardiac injury. The protective mechanisms uncovered here may be further explored in view of potential cardiotoxic effects of FLT3-targeting anticancer therapy, particularly in patients with ischemic heart disease. [Copyright &y& Elsevier]

Highlights: [•] Hypoxia and H-7 stimulate apoptotis in primary cultured locust brain neurons. [•] Apoptotic cell death is prevented by human recombinant erythropoietin. [•] Erythropoietin mediates neuroprotection through a janus kinase-associated receptor. [•] Neuroprotection depends on the activation of STAT transcription factors. [•] Neuroprotection is independent of PI3K signaling. [ABSTRACT FROM AUTHOR]

Abstract: Mobilization of stem cells and their differentiation into cardiomyocytes are known to have protective effects after myocardial infarction. The integrity of transplanted mesenchymal stem cells for cardiac regeneration is dependent on cell–cell or cell–matrix interaction, which is adversely affected by reactive oxygen species in an ischemic environment. Treatment with erythropoietin was shown to protect human adipose tissue derived mesenchymal stem cells in an ischemic injury in vitro model. The analyses indicated that expression of erythropoietin receptors played a pivotal role in erythropoietin mediated cell survival. In this study, the anti-apoptotic effect of erythropoietin on stem cells was analyzed in apoptosis-induced human mesenchymal stem cells. Apoptosis was induced in cultured adult human adipose tissue derived mesenchymal stem cells by hydrogen peroxide. A group of cultured cells was also treated with recombinant human erythropoietin in a concentration of 50ngmL−1. The degree of apoptosis was analyzed by flow-cytometry and immunohistochemical staining for Caspase 3. The average percentages of apoptotic cells were significantly higher in H2O2-induced stem cells than in cells co-cultured with erythropoietin (63.03±4.96% vs 29±3.41%, p <0.01). We conclude that preconditioning with erythropoietin suppresses apoptosis of mesenchymal stem cells and enhances their survival. [Copyright &y& Elsevier]

Abstract: Diabetic retinopathy (DR) has mainly been regarded as a microvascular disease that is caused by hyperglycaemia and characterized by retinal vascular leakage, macular oedema and preretinal neovascularisation. Increasing clinical evidence from electroretinographic, contrast sensitivity, perimetric, and colour vision studies suggest that neuronal changes may occur prior to clinically detectable microvasculopathy. Thus, there may be a primary neurodegenerative process which contributes to loss of vision in DR. Neuronal apoptosis in DR has been reported both in vivo and in vitro. Consequently, neuroprotection in DR may be a valuable therapeutic target. This review outlines the recent new concepts of neurodegeneration in the pathogenesis of DR, particularly emphasising its potential for new therapeutic approaches. [Copyright &y& Elsevier]

Abstract: Hypoxia-inducible factor 1α (HIF-1α) is a master regulator of cellular adaptation to hypoxia and has been proposed as a potent therapeutic target for cerebral ischemia. However, research on the expression and effects of HIF-1α in subarachnoid hemorrhage (SAH) is limited. The aim of the present study was to investigate the expression of HIF-1α in the hippocampus and its possible protective effect against hippocampal apoptosis and cognitive dysfunction in a rat model of SAH. Seventy-two Sprague–Dawley (SD) rats were randomly divided into the sham group, the SAH+vehicle group, and the SAH+YC-1 group. Immunohistochemical staining and western blotting analyses revealed that the expression of HIF-1α and its downstream effectors, vascular endothelial growth factor (VEGF), erythropoietin (EPO), and glucose transporter 1 (GLUT1), increased in the hippocampus 48h after the induction of SAH. YC-1 blocked this upregulation. The number of active caspase-3-positive cells and the expression of active caspase-3 in the hippocampus significantly increased in the YC-1 group relative to the vehicle group. A cell death assay further revealed that DNA fragmentation was significantly increased at 48h in the YC-1 group compared with the vehicle group. In Morris water maze (MWM) tests, the YC-1 group showed increased escape latency times and distances as well as reduced time spent and distance traveled in the target quadrant. These results indicate that hippocampal apoptosis increased and cognitive function deteriorated when HIF-1α was inhibited, suggesting that HIF-1α has a neuroprotective effect in SAH and may represent an effective therapeutic target. [Copyright &y& Elsevier]

Background: Although it was initially assumed that erythropoietin (EPO) was a hormone that only affected erythropoiesis, it has now been proposed that EPO plays an additional key role in the regulation of acute and chronic tissue damage.Methods/design: This is a large, prospective, randomized, double-blind, multi-center study, funded by the German Federal Ministry of Education and Research, and fully approved by the designated ethics committee. The trial, which is to investigate the effects of EPO in severely burned patients, is in its recruitment phase and is being carried out in 13 German burn care centers. A total of 150 patients are to be enrolled to receive study medication every other day for 21 days (EPO 150 IU/kg body weight or placebo). A follow-up of one year is planned. The primary endpoint of this study is the time until complete re-epithelialization of a defined skin graft donor site is reached. Furthermore, clinical parameters such as wound healing, scar formation (using the Vancouver scar scale), laboratory values, quality of life (SF-36), angiogenic effects, and gene- and protein-expression patterns are to be determined. The results will be carefully evaluated for gender differences.Discussion: We are seeking new insights into the mechanisms of wound healing in thermally injured patients and more detailed information about the role EPO plays, specifically in these complex interactions. We additionally expect that the biomimetic effects of EPO will be useful in the treatment of acute thermal dermal injuries.Trial Registration: EudraCT Number: 2006-002886-38, Protocol Number: 0506, ISRCT Number: http://controlled-trials.com/ISRCTN95777824/ISRCTN95777824. [ABSTRACT FROM AUTHOR]

Until recently the major physiological function of erythropoietin (EPO) was thought to be the induction of erythropoiesis. However, a growing body of evidence indicates that EPO has tissue-protective properties and prevents ischemia induced tissue damage in several organs including the kidney. A pivotal intracellular pathway mediating the beneficial effects of EPO is the activation of Akt, i.e. serine/threonine protein kinase B. As a result, Akt phosphorylates the proapoptotic factor Bad, which in turn causes inhibition of programmed cell death (apoptosis). In the present article we review data on the non-hematological effects of recombinant human EPO (rHuEPO) in different experimental settings of acute and chronic kidney injury, and discuss clinical renoprotective strategies with rHuEPO or analogues substances that are not related to anemia correction. [ABSTRACT FROM AUTHOR]

Selective neuronal loss following status epilepticus(SE) was first described just under 100 years ago. The acute pathology following SE was shown to be 'ischemic cell change' and was assumed to arise through hypoxia/ischemia. Recently, erythropoietin (Epo) has been shown to have potent anti-apoptosis activity in central nervous system neurons in animal models of ischaemic injury. Aims: In this report, in order to determine Epo preconditioning on hippocampus neuronal apoptosis, we examined caspase-3 expression following SE caused by Li-pilocarpine in rats. Settings and Design: Animals were classified into three groups: EP group (pilocarpine group), rhEpo-pilocarpine group and control group. Four hours after preconditioning with Epo intraperitoneally, pilocarpine hydrochloride was administered intraperitoneally and observed for behavioral manifestations of SE. The animals were sacrificed at one hour after SE onset. Materials and Methods: At the abovementioned time point, animals were deeply anesthetized and were perfused through the left ventricle. Detection of hippocampus neuronal apoptosis was performed with caspase-3 immunohistochemical technique on three groups. To further confirm which cell population upregulates caspase-3, brain sections were stained for NeuN (green) and caspase-3 (red).Statistical analysis ANOVA and Fisher's post hoc test was used. Results Quatification of hippocampus neurons revealed that the number of caspase-3-positive cells in the CA1/CA3 area and dentate gyrus(DG)of three groups had a significant difference. In comparison with control group, there was an increase by 74% and 534%, 42% and 272% in the CA1/CA3 area and DG of EP group and rhEpo-treated group respectively. There was a decrease by 18% and 26% in the CA1/CA3 area and DG of rhEpo-treated group compared with those in EP group. In addition, colocalization of caspase-3 with NeuN was shown. Conclusions Systemic rhEpo therapy reduced caspase-3 expression in SE induced by Li-pilocarpine. [ABSTRACT FROM AUTHOR]

There is growing evidence linking the pathophysiology of lung disease to an imbalance state of reduction–oxidation (redox) equilibrium. The therapeutic potential of glutathione, an ubiquitous sulfhydryl thiol, and its immunopharmacological properties in the airway epithelium bears clinical consequences for the paediatric treatment of respiratory distress (RD). Dynamic variation in alveolar pO2 and its effect on redox state may impose a direct role in modulating the pattern of gene expression in lung tissues and, accordingly, could be pivotal in determining cellular fate under these conditions. Hypoxia-inducible factor-1α (HIF-1α) and nuclear factor-κB (NF-κB) are redox-sensitive transcription factors of particular importance because their differential activation by reducing and oxidizing signals, respectively, regulate the expression/suppression of O2-responsive genes. The regulation of these transcription factors, therefore, which is redox sensitive, is consistent with their roles in coordinating adaptive homeostatic responses to oxidative stress. Functionally, the relationship between O2, glutathione biosynthesis and transcription factor activity bears typical implications for the pattern of cellular survivorship and alveolarization on exposure to O2-linked stresses. In this review, I discuss (1) the HIF-1α/NF-κB responsiveness to dynamic changes in pO2 characteristic of the transition period from placental to pulmonary-based respiration, (2) the capacity of the alveolar epithelium to engage in glutathione biosynthesis and redox shuttling, effectively forming a feedback mechanism governing gene expression, (3) the restitution of antioxidant/prooxidant equilibrium following oxidative challenge and its dependency on the adaptive coordination of responses between redox-associated signalling pathways controlling apoptosis and genetic regulatory factors and (4) a likely association between oxidative stress and the evolution of an inflammatory signal through the pleiotropic O2-sensitive cytokines. [Copyright &y& Elsevier]