Cervical cancer is the third most common type of cancer in women worldwide and radiotherapy remains its predominant therapeutic treatment. Artesunate (ART), a derivative of artemisinin, has shown radiosensitization effect in previous studies. However, such effects of ART have not yet been revealed for cervical cancer cells.
Accumulated evidence indicates that inflammation plays a critical role in the progression of many renal diseases. Fluorofenidone (AKF-PD) has been shown to attenuate renal fibrosis in a number of experimental renal fibrosis models. The aim of this study was to assess the anti-inflammatory effect of AKF-PD.
The current treatment for advanced nonsmall cell lung cancer (NSCLC) remains unsatisfactory due to resistance to chemotherapy and ionizing radiation. The ubiquitin-proteasome system (UPS) regulates multiple cellular processes that are crucial for the proliferation and survival of all kinds of cells. Carbobenzoxyl-leucinyl-leucinyl-leucinal-H (MG132), a specific and selective reversible inhibitor of the 26S proteasome, represents a novel approach for cancer therapy. However, whether MG132 can potentiate the effect of radiation against the growth and metastasis of NSCLC is not clear. We found that MG132 inhibited the proliferation of human NSCLC cell lines (A549 and H1299) in a dose- and time-dependent manner by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Then MG132 at a nontoxic dose (100 nM) was selected for following studies. Pretreatment of A549 and H1299 cells with 100 nM MG132 before ionizing radiation (IR) potentiated the anticancer effect of IR. Moreover, pretreatment with 100 nM MG132 before IR-enhanced radiation induced cell cycle arrest by decreased CyclinD1 but increased Wee1 expression in A549 and H1299 cells. In addition, pretreatment of MG132 combined with IR significantly suppressed cell migration and invasion abilities in NSCLC cell lines, which was accompanied by decreased expression of matrix metalloproteinase (MMP)-2 and MMP-9 in NSCLC cell lines. Taken together, our results demonstrate that MG132 enhances the antigrowth and antimetastatic effects of irradiation in NSCLC cells by modulating expression of cell cycle and invasion- related genes.
Radiation-induced skin injury is a serious concern during radiotherapy. However, the molecular mechanism underlying the pathogenesis of radiation-induced skin injury has not been extensively reported. Most biological functions are performed and regulated by proteins and noncoding RNAs, including microRNAs (miRNAs). The interplay between mRNA and miRNA has been implicated in disease initiation and progression. Technical advances in genomics and proteomics have enabled the exploration of the etiology of diseases and have the potential to broaden our understanding of the molecular pathogenesis of radiation-induced skin injury. In this study, we compared the protein and miRNA expression in rat skin irradiated with a 45-Gy electron beam with expression from adjacent normal tissues. We found 24 preferentially expressed proteins and 12 dysregulated miRNAs in irradiated skin. By analyzing the protein and miRNA profiles using bioinformatics tools, we identified a possible interaction between miR-214 and peroxiredoxin-6 (PRDX-6). Next, we investigated the expression of PRDX-6 and the consequences of its dysregulation. PRDX-6 is suppressed by radiation-inducible miR-214 and is involved in the pathogenesis of radiation-induced skin injury. Overexpression of PRDX-6 conferred radioresistance on cells, decreased cell apoptosis, and preserved mitochondrial integrity after radiation exposure. In addition, in vivo transfection with PRDX-6 reduced radiation-induced reactive oxygen species and the malondialdehyde concentration and ameliorated radiation-induced skin damage in rats. Our present findings illustrate the molecular changes during radiation-induced skin injury and the important role of PRDX-6 in ameliorating this damage in rats.
Radiation-induced skin injury remains a serious concern during radiotherapy. Cu/Zn-superoxide dismutase (Cu/Zn-SOD, SOD1) is a conserved enzyme for scavenging superoxide radical in cells. Because of the integrity of cell membranes, exogenous molecule is not able to be incorporated into cells, which limited the application of natural SOD1. The aim of this study was to evaluate the protective role of HIV-TAT protein transduction domain mediated protein transduction of SOD1 (TAT-SOD1) against ionizing radiation.
Hematopoietic stem cells (HSCs) are protected in a metabolically dormant state within the bone marrow stem cell niche. Inflammation has been shown to disrupt HSC dormancy and cause multiple functional changes. Here, we investigated whether HSC functions were altered in systemic lupus erythematosus (SLE)-prone mice and whether this contributed to clinical manifestations of SLE. We found that HSCs were significantly expanded in lupus mice. The increase in HSC cellularity was caused by both genetic lupus risk factors and inflammatory cytokines in lupus mice. In addition, the inflammatory conditions of lupus led to HSC mobilization and lineage-biased hematopoiesis. Strikingly, these functionally altered HSCs possessed robust self-renewal capacity and exhibited repopulating advantages over wild-type HSCs. A single-nucleotide polymorphism in the cdkn2c gene encoding p18(INK4c) within a SLE susceptibility locus was found to account for reduced p18(INK4c) expression and the increase in HSC self-renewal capacity in lupus mice. Lupus HSCs with enhanced self-renewal capacity and resistance to stress may compete out transplanted healthy HSCs, thereby leading to relapses after HSC transplantation.
An electrochemical lead sensor is developed on DNA-based vertically aligned conductive carbon hybridized TiO(2) nanotube arrays (DNA/C-TiO(2) NTs). The designed DNA/C-TiO(2) NTs sensor is superior in determination of lead with high sensitivity, selectivity and repeatability, as well as wide pH adaptability, fast electro-accumulation capacity for lead and easy regeneration. Such remarkable characteristics for lead sensing are attributed to the immobilization of abundant target biomolecules, DNA, and the enhanced bioelectrochemical activity. The controllable carbon hybridization of the TiO(2) NTs increases the conductivity of the electrode, while retaining the tubular structure, biocompatibility, and hydrophilicity. The results show that the lead sensor possesses a wide linear calibration ranging from 0.01 to 160 nM with the detection limitation at a picomole level (3.3 pM). The application of the present sensor is realized for determination of Pb(2+) in real water samples.
The pathogenesis of sepsis is mediated in part by bacterial endotoxin, which stimulates macrophages/monocytes to sequentially release proinflammatory factors like TNF-alpha and IL-1beta. Fluorofenidone (AKF-PD) is a novel pyridone agent, which exerts a strong antifibrotic effect. In this work, we showed that AKF-PD also exert an inhibitory effect on acute systemic inflammatory response. AKF-PD treatment significantly increased survival in animals with established endotoxemia. In addition, AKF-PD treatment significantly reduced circulating levels of TNF-alpha and IL-1beta during endotoxemia. In macrophage cultures, AKF-PD inhibited the release of TNF-alpha and IL-1beta in a dose-dependent manner. In conclusion, these results indicate that AKF-PD inhibits the release of the proinflammatory cytokines (TNF-a and IL-1beta) and improves survival during lethal endotoxemia, which suggest this new pyridone agent can be a novel candidate for therapy of septic shock.
High-mobility group box 1 protein (HMGB1), an abundant nuclear protein, was recently established as a proinflammatory mediator of experimental sepsis. Although extracellular HMGB1 has been found in atherosclerotic plaques, its potential role in the pathogenesis of atherothrombosis remains elusive. In the present study, we determined whether HMGB1 induces tissue factor (TF) expression in vascular endothelial cells (ECs) and macrophages. Our data showed that HMGB1 stimulated ECs to express TF (but not TF pathway inhibitor) mRNA and protein in a concentration- and time-dependent manner. Blockade of cell surface receptors (including TLR4, TLR2, and RAGE) with specific neutralising antibodies partially reduced HMGB1-induced TF expression. Moreover, HMGB1 increased expression of Egr-1 and nuclear translocation of NF-kappaB (c-Rel/p65) in ECs. Taken together, our data suggest that HMGB1 induces TF expression in vascular endothelial cells via cell surface receptors (TLR4, TLR2, and RAGE), and through activation of transcription factors (NF-kappaB and Egr-1).
Tissue factor (TF), which is expressed on the surface of activated monocytes, is the major procoagulant that initiates thrombus formation in sepsis. Two endogenous neuropeptides, vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP), are attractive candidates for the development of therapies against septic shock. The purpose of this study was to examine whether VIP or PACAP inhibit the LPS-induced TF expression in monocytes. Treatment of freshly isolated human monocytes or cultured monocytic THP-1 cells with VIP or PACAP leads to reduced LPS-induced TF protein, mRNA expression and activity, as demonstrated by Western blot, real-time polymerase chain reaction, and TF activity assay, respectively. In an endotoxemic model, VIP blunts the increase of LPS-induced TF expression in blood cells at the transcriptional level, as demonstrated by real-time polymerase chain reaction. However, neither neuropeptide affects the expression of TF pathway inhibitor in monocytes. In vitro, LPS increases the migration of c-Rel/p65 into the nucleus and the phosphorylation of p38 and JNK, all of which are essential for LPS-induced TF expression. In addition, interestingly, VIP and PACAP block both the migration of c-Rel/p65 and the phosphorylation of p38 and JNK, as demonstrated by Western blot analysis. These data indicate that VIP and PACAP inhibit LPS-induced TF expression in monocytes in vitro and in vivo, confirming these peptides as candidates for the multitarget therapy of septic shock.
Mipu1, a novel gene encoding a KRAB/C2H2 zinc finger protein, was first reported to be up-regulated in myocardial ischemia-reperfusion injury, functioning to protect cells against oxidative stress. To map the promoter region of the gene and to understand its regulation, we identified the transcription start site and revealed that the 1366-bp fragment upstream of the transcription start site possesses promoter activity. Deletion constructs of the 5-flanking region of Mipu1 lead to the identification of a minimal promoter, in which neither a TATA box nor a CAAT box was detected. Two GC boxes were found; however, they are the specific binding sites for Sp1-family transcription factors. Mutations in these GC boxes resulted in the total loss of Mipu1 minimal promoter activity. Finally, WP631, an Sp1-family-specific inhibitor, was found to decrease the promoter activity in a dose-dependent manner, indicating that the GC boxes are essential for the activity of the Mipu1 minimal promoter activity.
The inflammasome regulates the release of caspase activation-dependent cytokines, including interleukin (IL)-1?, IL-18 and high-mobility group box 1 (HMGB1). By studying HMGB1 release mechanisms, here we identify a role for double-stranded RNA-dependent protein kinase (PKR, also known as EIF2AK2) in inflammasome activation. Exposure of macrophages to inflammasome agonists induced PKR autophosphorylation. PKR inactivation by genetic deletion or pharmacological inhibition severely impaired inflammasome activation in response to double-stranded RNA, ATP, monosodium urate, adjuvant aluminium, rotenone, live Escherichia coli, anthrax lethal toxin, DNA transfection and Salmonella typhimurium infection. PKR deficiency significantly inhibited the secretion of IL-1?, IL-18 and HMGB1 in E. coli-induced peritonitis. PKR physically interacts with several inflammasome components, including NOD-like receptor (NLR) family pyrin domain-containing 3 (NLRP3), NLRP1, NLR family CARD domain-containing protein 4 (NLRC4), absent in melanoma 2 (AIM2), and broadly regulates inflammasome activation. PKR autophosphorylation in a cell-free system with recombinant NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC, also known as PYCARD) and pro-caspase-1 reconstitutes inflammasome activity. These results show a crucial role for PKR in inflammasome activation, and indicate that it should be possible to pharmacologically target this molecule to treat inflammation.
Follicular atresia is common in female mammalian ovaries, where most follicles undergo degeneration at any stage of growth and development. Oxidative stress gives rise to triggering granulosa cell apoptosis, which has been suggested as a major cause of follicular atresia. However, the underlying mechanism by which the oxidative stress induces follicular atresia remains unclear. FoxO transcription factors are known as critical mediators in the regulation of oxidative stress and apoptosis. In this study, the involvement of FoxO1 in oxidative stress-induced apoptosis of mouse follicular granulosa cells (MGCs) was investigated in vivo and in vitro. It was observed that increased apoptotic signals correlated with elevated expression of FoxO1 in MGCs when mice were treated with the oxidant. Correspondingly, the expressions of FoxO1 target genes, such as proapoptotic genes and antioxidative genes, were also up-regulated. In primary cultured MGCs, treatment with H(2)O(2) led to FoxO1 nuclear translocation. Further studies with overexpression and knockdown of FoxO1 demonstrated the critical role of FoxO1 in the induction of MGC apoptosis by oxidative stress. Finally, inactivation of FoxO1 by insulin treatment confirmed that FoxO1 induced by oxidative stress played a pivotal role in up-regulating the expression of downstream apoptosis-related genes in MGCs. Our results suggest that up-regulation of FoxO1 by oxidative stress leads to apoptosis of granulosa cells, which eventually results in follicular atresia in mice.
Recent developments in nanoscience research have demonstrated that DNA switches (rationally designed DNA nanostructures) constitute a class of versatile building blocks for the fabrication and assembly of electronic devices and sensors at the nanoscale. Functional DNA sequences and structures such as aptamers, DNAzymes, G-quadruplexes, and i-motifs can be readily prepared in vitro, and subsequently adapted to an electrochemical platform by coupling with redox reporters. The conformational or conduction switching of such electrode-bound DNA modules in response to an external stimulus can then be monitored by conventional voltammetric measurements. In this review, we describe how we are able to design and examine functional DNA switches, particularly those systems that utilize electrochemical signaling. We also discuss different available options for labeling functional DNA with redox reporters, and comment on the function-oriented signaling pathways.
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