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Incidence of dengue virus (DENV) and Zika virus (ZIKV), two mosquito-borne flaviviruses, is increasing in large parts of the world. Vaccination and medication for these diseases are unsatisfactory. Here, we developed a novel antiviral approach, using a virus-inducible gene expression system, to block virus replication and transmission. Constructs containing the smallest replication units of dengue virus serotype 2 (DENV2) with negative-stranded DENV2 artificial genomes and genes of interest were established in an Aedes aegypti cell line, resulting in expression of target genes after DENV2 infection. Green fluorescent protein (GFP) assays confirmed the system was virus-inducible. When we used one of two apoptosis-related genes, A. aegypti michelob_x (AaMx) and inhibitor of apoptosis (IAP)-antagonist michelob_x-like protein (AaIMP) instead of GFP, the production of viral RNA and proteins were inhibited for all five viruses tested (DENV1–4 and ZIKV), and effector caspase activity was induced. The system thus inhibited the production of infectious virus particles in vitro , and in mosquitoes it did so after DENV2 infection. This is a novel broad-spectrum antiviral approach using a flavivirus-inducible gene-expression system, which could lead to new avenues for mosquito-borne disease control. [Display omitted] • A virus-inducible gene expression system was developed to block virus replication and transmission. • The system was activated upon dengue and Zika viruses infection, leading to the production of two apoptosis-related genes. • A bacteria-based delivery approach was established to generate mosquitoes with antiviral activity. [ABSTRACT FROM AUTHOR]

Background: Breast cancer is the malignant tumor with the highest incidence in women. DNA methylation has an important effect on breast cancer, but the effect of abnormal DNA methylation on gene expression in breast cancer is still unclear. Therefore, it is very important to find therapeutic targets related to DNA methylation. Results: In this work, we calculated the DNA methylation distribution and gene expression level in cancer and para-cancerous tissues for breast cancer samples. We found that DNA methylation in key regions is closely related to gene expression by analyzing the relationship between the distribution characteristics of DNA methylation in different regions and the change of gene expression level. Finally, the 18 key genes (17 tumor suppressor genes and 1 oncogene) related to prognosis were confirmed by the survival analysis of clinical data. Some important DNA methylation regions in these genes that result in breast cancer were found. Conclusions: We believe that 17 TSGs and 1 oncogene may be breast cancer biomarkers regulated by DNA methylation in key regions. These results will help to explore DNA methylation biomarkers as potential therapeutic targets for breast cancer. [ABSTRACT FROM AUTHOR]

Background: Breast cancer is the malignant tumor with the highest incidence in women. DNA methylation has an important effect on breast cancer, but the effect of abnormal DNA methylation on gene expression in breast cancer is still unclear. Therefore, it is very important to find therapeutic targets related to DNA methylation. Results: In this work, we calculated the DNA methylation distribution and gene expression level in cancer and para-cancerous tissues for breast cancer samples. We found that DNA methylation in key regions is closely related to gene expression by analyzing the relationship between the distribution characteristics of DNA methylation in different regions and the change of gene expression level. Finally, the 18 key genes (17 tumor suppressor genes and 1 oncogene) related to prognosis were confirmed by the survival analysis of clinical data. Some important DNA methylation regions in these genes that result in breast cancer were found. Conclusions: We believe that 17 TSGs and 1 oncogene may be breast cancer biomarkers regulated by DNA methylation in key regions. These results will help to explore DNA methylation biomarkers as potential therapeutic targets for breast cancer. [ABSTRACT FROM AUTHOR]

Background: Breast cancer is the malignant tumor with the highest incidence in women. DNA methylation has an important effect on breast cancer, but the effect of abnormal DNA methylation on gene expression in breast cancer is still unclear. Therefore, it is very important to find therapeutic targets related to DNA methylation. Results: In this work, we calculated the DNA methylation distribution and gene expression level in cancer and para-cancerous tissues for breast cancer samples. We found that DNA methylation in key regions is closely related to gene expression by analyzing the relationship between the distribution characteristics of DNA methylation in different regions and the change of gene expression level. Finally, the 18 key genes (17 tumor suppressor genes and 1 oncogene) related to prognosis were confirmed by the survival analysis of clinical data. Some important DNA methylation regions in these genes that result in breast cancer were found. Conclusions: We believe that 17 TSGs and 1 oncogene may be breast cancer biomarkers regulated by DNA methylation in key regions. These results will help to explore DNA methylation biomarkers as potential therapeutic targets for breast cancer. [ABSTRACT FROM AUTHOR]

Age-related myocardial dysfunction is a very large healthcare burden. Here, we aimed to investigate whether ginsenoside Rb1 (Rb1) improves age-related myocardial dysfunction and to identify the relevant molecular mechanism. Young mice and aged mice were injected with Rb1 or vehicle for 3 months. Then, their cardiac function was inspected by transthoracic echocardiography. Serum and myocardium tissue were collected from all mice for histological or molecular expression analyses, including aging-related proteins, markers relevant to fibrosis and inflammation, and markers indicating the activation of the nuclear factor-kappa B (NF- κ B) pathway. Compared with the control condition, Rb1 treatment significantly increased the ejection fraction percentage and significantly decreased the internal diameter and volume of the left ventricle at the end-systolic and end-diastolic phases in aged mice. Rb1 treatment reduced collagen deposition and collagen I, collagen III, and transforming growth factor- β 1 protein expression levels in aged hearts. Rb1 also decreased the aging-induced myocardial inflammatory response, as measured by serum or myocardial interleukin-6 and tumor necrosis factor- α levels. Furthermore, Rb1 treatment in aged mice increased cytoplasmic NF- κ B but decreased nuclear NF- κ B, which indicated the suppression of the NF- κ B signaling pathway by regulating the translocation of NF- κ B. Rb1 could alleviate aging-related myocardial dysfunction by suppressing fibrosis and inflammation, which is potentially associated with regulation of the NF- κ B signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Understanding molecular mechanisms underlying the induction of learning and memory impairments remains a challenge. Recent investigations have shown that the activation of group I mGluRs (mGluR1 and mGluR5) in cultured hippocampal neurons by application of (S)-3,5-Dihydroxyphenylglycine (DHPG) causes the regulated internalization of N-methyl-D-aspartate receptors (NMDARs), which subsequently activates protein kinase D1 (PKD1). Through phosphorylating the C-terminals of the NMDAR GluN2 subunits, PKD1 down-regulates the activity of remaining (non-internalized) surface NMDARs. The knockdown of PKD1 does not affect the DHPG-induced inhibition of AMPA receptor-mediated miniature excitatory post-synaptic currents (mEPSCs) but prevents the DHPG-induced inhibition of NMDAR-mediated mEPSCs in vitro. Thus, we investigated the in vivo effects of bilateral infusions of DHPG into the hippocampal CA1 area of rats in the Morris water maze (MWM) and the novel object discrimination (NOD) tests. Methods: A total of 300 adult male Sprague Dawley rats (250–280 g) were used for behavioral tests. One hundred ninety four were used in MWM test and the other 106 rats in the NOD test. Following one week of habituation to the vivarium, rats were bilaterally implanted under deep anesthesia with cannulas aimed at the CA1 area of the hippocampus (CA1 coordinates in mm from Bregma: AP -3.14; lateral +/-2; DV -3.0). Through implanted cannulas artificial cerebrospinal fluid (ACSF), the group1 mGluR antagonist 6-Methyl-2-(phenylethynyl)pyridine (MPEP), the dynamin-dependent internalization inhibitor Dynasore, or the PKD1 inhibitor CID755673 were infused into the bilateral hippocampal CA1 areas (2 μL per side, over 5 min). The effects of these infusions and the effects of PKD1 knockdown were examined in MWM or NOD test. Results: DHPG infusion increased the latency to reach the platform in the MWM test and reduced the preference for the novel object in the NOD task. We found that the DHPG effects were dose-dependent and could be maintained for up to 2 days. Notably, these effects could be prevented by pre-infusion of the group1 mGluR antagonist MPEP, the dynamin-dependent internalization inhibitor Dynasore, the PKD1 inhibitor CID755673, or by PKD1 knockdown in the hippocampal CA1 area. Conclusion: Altogether, these findings provide direct evidence that PKD1-mediated signaling may play a critical role in the induction of learning and memory impairments by DHPG infusion into the hippocampal CA1 area. [ABSTRACT FROM AUTHOR]

Sonodynamic therapy (SDT), a promising modality for cancer treatment, involves the synergistic interaction of ultrasound and some chemical compounds termed sonosensitizers . However, its effect on pancreatic cancer cells remains unclear. In our study, we sought to identify the cytotoxic effects of ultrasound-activated 5- aminolevulinic acid on human pancreatic cancer Capan-1 cells. Cell viability was determined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide) analysis; mitochondrial membrane potential was assessed using the fluorescent probe jc-1; apoptosis was evaluated by flow cytometry; cell morphology was investigated by scanning electron microscopy; apoptosis-related protein expression was analyzed by Western blot assay. We found that SDT significantly decreased the survival rate of cells, and this effect increased with 5- aminolevulinic acid concentration and ultrasound exposure time. The mechanism underlying the effect of SDT involves, in part, the induction of a conspicuous loss in mitochondrial membrane potential and, in part, the induction of apoptosis through upregulation of Bax expression, downregulation of Bcl-2 and increased activation of procaspase-3. These results indicate that the ultrasonically induced cell killing effect could be enhanced by 5-ALA and that the mitochondrial pathway might be involved in the cell damage process. We conclude that SDT is a promising new methodology for pancreatic cancer treatment. [ABSTRACT FROM AUTHOR]

Background: Interleukin (IL)-17A, a newly identified cytokine, may participate in the transition of a stable plaque into an unstable plaque. Macrophages play a critical role in the destabilization of atherosclerotic plaque. Methods: RAW 264.7 cells were stimulated with IL-17A. The mRNA expression of inflammatory cytokines was determined by RT-PCR. The cytokines production in the supernatants was measured by ELISA. Small interfering RNA (siRNA) was used to confirm that IL-17A-induced pro-inflammatory cytokines production via IL-17RA signaling. The western blot assay was used to detect the phosphorylation of MAPKinases including p38 and ERK1/2. The DNA binding activity of nuclear factor NF-κB and AP-1 were detected by EMSA. Results: IL-17A induced the production of pro-inflammatory cytokines in macrophages in a time- and dose-dependent manner, such as tumor necrosis factor (TNF)-α, IL-1β, and IL-6. Meanwhile, IL-17A resulted in the phosphorylation of p38 and ERK1/2 and increased DNA-binding activity of NF-κB and AP-1. Pharmacological inhibitors of p38 and ERK1/2 partly attenuated IL-17A-induced TNF-α, IL-1β, and IL-6 production. Either NF-κB inhibitor or AP-1 inhibitor also partly decreased the IL-17A-induced cytokine production. Conclusions: IL-17A induces pro-inflammatory cytokines production in macrophages via MAPKinases, NF-κB and AP-1 pathway. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

To complement the molecular pathways contributing to Parkinson's disease (PD) and identify potential biomarkers, gene expression profiles of two regions of the medulla were compared between PD patients and control. GSE19587 containing two groups of gene expression profiles [6 dorsal motor nucleus of the vagus (DMNV) samples from PD patients and 5 from controls, 6 inferior olivary nucleus (ION) samples from PD patients and 5 from controls] was downloaded from Gene Expression Omnibus. As a result, a total of 1569 and 1647 differentially expressed genes (DEGs) were, respectively, screened in DMNV and ION with limma package of R. The functional enrichment analysis by DAVID server (the Database for Annotation, Visualization and Integrated Discovery) indicated that the above DEGs may be involved in the following processes, such as regulation of cell proliferation, positive regulation of macromolecule metabolic process, and regulation of apoptosis. Further analysis showed that there were 365 common DEGs presented in both regions (DMNV and ION), which may be further regulated by eight clusters of microRNAs retrieved with WebGestalt. The genes in the common DEGs-miRNAs regulatory network were enriched in regulation of apoptosis process via DAVID analysis. These findings could not only advance the understandings about the pathogenesis of PD, but also suggest potential biomarkers for this disease. [ABSTRACT FROM AUTHOR]

Abstract: Neuronal Src (n-Src) is an alternative isoform of Src kinase containing a 6-amino acid insert in the SH3 domain that is highly expressed in neurons of the central nervous system (CNS). To investigate the function of n-Src, wild-type n-Src, constitutively active n-Src in which the C-tail tyrosine 535 was mutated to phenylalanine (n-Src/Y535F) and inactive n-Src in which the lysine 303 was mutated to arginine in addition to the mutation of Y535F (n-Src/K303R/Y535F), were expressed and purified from Escherichia coli BL21(DE3) cells. We found that all three types of n-Src constructs expressed at very high yields (∼500mg/L) at 37°C, but formed inclusion bodies. In the presence of 8M urea these proteins could be solubilized, purified under denaturing conditions, and subsequently refolded in the presence of arginine (0.5M). These Src proteins were enzymatically active except for the n-Src/K303R/Y535F mutant. n-Src proteins expressed at 18°C were soluble, albeit at lower yields (∼10–20mg/L). The lowest yields were for n-Src/Y535F (∼10mg/L) and the highest for n-Src/K303R/Y535F (∼20mg/L). We characterized the purified n-Src proteins expressed at 18°C. We found that altering n-Src enzyme activity either pharmacologically (e.g., application of ATP or a Src inhibitor) or genetically (mutation of Y535 or K303) was consistently associated with changes in n-Src stability: an increase in n-Src activity was coupled with a decrease in n-Src stability and vice versa. These findings, therefore, indicate that n-Src activity and stability are interdependent. Finally, the successful production of functionally active n-Src in this study indicates that the bacterial expression system may be a useful protein source in future investigations of n-Src regulation and function. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Atherosclerosis is a chronic inflammatory disease regulated by T lymphocyte subsets. Recently, CD4+ CD25+ Foxp3+ regulatory T (Treg) cells and Th17 cells have been described as two distinct subsets and have the opposite effects on autoimmunity. Clinical observation has revealed that the Th17/Treg imbalance exists in patients with acute coronary syndrome. We investigated whether the Th17/Treg functional imbalance existed during atherogenesis in ApoE−/− mice. Methods and results: Th17/Treg functions at different levels including cell frequencies, related cytokine secretion and key transcription factors were investigated comparatively between ApoE−/− mice and their age-matched C57BL/6J mice. The results demonstrated that ApoE−/− mice revealed significantly increased secretion of Th17 related cytokines (IL-17 and IL-6) and expression of transcription factor (RORγt) levels and obviously decreased number in Treg cells, secretion of Treg related cytokines (TGF-β1) and expression of transcription factor (Foxp3) levels as compared with age-matched C57BL/6J mice. Th17 related mediators reached their maximum expression values at the early stage (8–16weeks of age) in ApoE−/− mice, and then followed by continuous depression of their expression levels. Meanwhile, the expression of Treg related mediators was much lower in ApoE−/− mice than in their age-matched wild-type littermates. Conclusions: Th17/Treg functional imbalance exists during atherogenesis in ApoE−/− mice, suggesting a potential role of Th17/Treg imbalance in the formation and progression of atherosclerosis. [Copyright &y& Elsevier]

G2 pea exhibits an apical senescence delaying phenotype under short-day (SD) conditions; however, the structural basis for its apical development is still largely unknown. In the present study, the apical meristem of SD-grown G2 pea plants underwent a transition from vegetative to indeterminate inflorescence meristem, but the apical meristem of long-day (LD)-grown G2 pea plants would be further converted to determinate floral meristem. Both SD signal and GA3 treatment enhanced expression of the putative calcium transporter PPF1, and pea homologs of TFL1 ( LF and DET), whereas LD signal suppressed their expression at 60 d post-flowering compared with those at 40 d post-flowering. Both PPF1 and LF expressed at the vegetative and reproductive phases in SD-grown apical buds, but floral initiation obviously increased the expression level of PPF1 compared with the unchanged expression level of LF from 40 to 60 d post-flowering. In addition, although the floral initiation significantly enhanced the expression levels of PPF1 and DET, DET was mainly expressed after floral initiation in SD-grown apical buds. Therefore, the main structural difference between LD- and SD-grown apical meristem in G2 pea lies in whether their apical indeterminate inflorescence meristem could be converted to the determinate structure. [ABSTRACT FROM AUTHOR]