Inhibition Of Protein Levels Research Articles

RNA m6A-mediated post-transcriptional repression of glucocorticoid receptor in LPS-activated Kupffer cells on broilers

Glucocorticoid receptors are distributed in various cells of the body and participate in the regulation of metabolism and immunity in response to glucocorticoids. RNA m6A methylation participates in various metabolic and inflammatory responses, yet it remains elusive whether m6A is involved in GR regulation during immune activation. Here, we observed uncoupled GR responses with increased mRNA yet suppressed protein levels in the LPS-challenged broilers chicken liver, in association with global elevation of RNA m6A methylation, especially in the expression of METTL3 and YTHDF2. Further analysis using isolated primary hepatocytes and Kupffer cells revealed that such uncoupled GR responses and m6A hypermethylation occurred specifically in KCs. The same GR and m6A responses were reproduced in LPS-activated KC cell line, implying a possible role of m6A in the post-transcriptional suppression of GR in KC. Indeed, m6A inhibitor cycloleucine alleviated LPS-induced GR protein suppression, whilst GR antagonist RU486 had no effect on global m6A methylation in KC. We observed that YTHDF2 siRNA can alleviate LPS-induced GR mRNA stability decrease. Subsequently, specific m6A sites on GR were predicted and verified. Mutation m6A sites and luciferase reporter assay was also applied to validate these findings. Mechanistically, m6A methylation on the transcripts of GR impairs its mRNA stability in a YTHDF2-dependent manner, which leads to the decrease of its protein. Our study indicates successive roles of RNA m6A modification in the down regulation of GR expression, which provides new drug targets for epigenetic therapy of liver inflammation.

The Potential of Enamel Matrix Derivative in Countering Bisphosphonate-Induced Effects in Osteoblasts.

The suppressive effect of bisphosphonates (BPs) on bone metabolism is considered to be a major cause of medication-related osteonecrosis of the jaw (MRONJ). Enamel matrix derivative (EMD) stimulates and activates growth factors, leading to the regeneration of periodontal tissues. In this study, we aimed to explore the potential of EMD in reversing the detrimental effects of BPs on human fetal osteoblasts (hFOBs) and osteosarcoma-derived immature osteoblasts (MG63s) by assessing cell viability, apoptosis, migration, gene expression, and protein synthesis. While the suppressive effect of zoledronate (Zol) on cell viability and migration was observed, the addition of EMD significantly mitigated this effect and enhanced cell viability and migration. Furthermore, an increased apoptosis rate induced by Zol was decreased with the addition of EMD. The decreased gene expression of alkaline phosphatase (ALP), osteocalcin (OC), and the receptor activator of nuclear factors kappa-B ligand (RANKL) caused by BP treatment was reversed by the co-addition of EMD to hFOB cells. This trend was also observed for ALP and bone sialoprotein (BSP) levels in MG63 cells. Furthermore, suppressed protein levels of OC, macrophage colony-stimulating factor (M-CSF), BSP, and type 1 collagen (COL1) were recovered following the addition of EMD. This finding suggests that EMD could mitigate the effects of BPs, resulting in the recovery of cell survival, migration, and gene and protein expression. However, the behavior of the osteoblasts was not fully restored, and further studies are necessary to confirm their effects at the cellular level and to assess their clinical usefulness in vivo for the prevention and treatment of MRONJ.

Hepatitis C Virus Dysregulates Polyamine and Proline Metabolism and Perturbs the Urea Cycle.

Hepatitis C virus (HCV) is an oncogenic virus that causes chronic liver disease in more than 80% of patients. During the last decade, efficient direct-acting antivirals were introduced into clinical practice. However, clearance of the virus does not reduce the risk of end-stage liver diseases to the level observed in patients who have never been infected. So, investigation of HCV pathogenesis is still warranted. Virus-induced changes in cell metabolism contribute to the development of HCV-associated liver pathologies. Here, we studied the impact of the virus on the metabolism of polyamines and proline as well as on the urea cycle, which plays a crucial role in liver function. It was found that HCV strongly suppresses the expression of arginase, a key enzyme of the urea cycle, leading to the accumulation of arginine, and up-regulates proline oxidase with a concomitant decrease in proline concentrations. The addition of exogenous proline moderately suppressed viral replication. HCV up-regulated transcription but suppressed protein levels of polyamine-metabolizing enzymes. This resulted in a decrease in polyamine content in infected cells. Finally, compounds targeting polyamine metabolism demonstrated pronounced antiviral activity, pointing to spermine and spermidine as compounds affecting HCV replication. These data expand our understanding of HCV's imprint on cell metabolism.

AMPK deficiency inhibits fatty acid oxidation in endothelial progenitor cells to aggravate impaired angiogenesis after ischemic stroke in hyperlipidemic mice

ABSTRACT Background Hyperlipidemia is a risk factor for stroke, and worsens neurological outcome after stroke. Endothelial progenitor cells (EPCs), which become dysfunctional in cerebral ischemia, hold capacity to promote revascularization. Objective We investigated the role of dyslipidemia in impairment of EPC-mediated angiogenesis in cerebral ischemic mice. Methods and Results The high fat diet (HFD)-fed mice following by ischemic stroke exhibited increased infarct volumes and neurological severity scores, and poorer angiogenesis. Bone marrow-EPCs treated with palmitic acid (PA) showed impaired functions and inhibited activity of AMP-activated protein kinase (AMPK). Notably, AMPK deficiency aggravated EPC dysfunction, further decreased mitochondrial membrane potential, and increased reactive oxygen species level in EPCs with PA treatment. Furthermore, the expression of fatty acid oxidation (FAO)-related genes was remarkably reduced, and carnitine palmitoyltransferase 1A (CPT1A) protein expression was downregulated in AMPK-deficient EPCs. AMPK deficiency aggravated neurological severity scores and angiogenesis in ischemic brain of HFD-fed mice, accompanied by suppressed protein level of CPT1A. EPC transplantation corrected impaired neurological severity scores and angiogenesis in AMPK-deficient mice. Conclusion Our findings suggest that AMPK deficiency aggravates poor angiogenesis in ischemic brain by mediating FAO and oxidative stress thereby inducing EPC dysfunction in hyperlipidemic mice.

Anti-rheumatoid arthritis effects of traditional Chinese medicine Fufang Xiaohuoluo pill on collagen-induced arthritis rats and MH7A cells.

Fufang Xiaohuoluo pill (FFXHL) is a commonly used prescription in clinical practice for treating rheumatoid arthritis in China, yet its specific mechanism remains unclear. This study aims to elucidate the pharmacological mechanisms of FFXHL using both in vivo and in vitro experiments. The collagen-induced arthritis (CIA) rat model was established to evaluate FFXHL's therapeutic impact. Parameters that include paw swelling, arthritis scores, and inflammatory markers were examined to assess the anti-inflammatory and analgesic effects of FFXHL. Human fibroblast-like synoviocytes (MH7A cells) is activated by tumour necrosis factor-alpha (TNF-α) were used to explore the anti-inflammatory mechanism on FFXHL. Our findings indicate that FFXHL effectively reduced paw swelling, joint pain, arthritis scores, and synovial pannus hyperplasia. It also lowered serum levels of TNF-α, interleukin-1β (IL1β), and interleukin-6 (IL-6). Immunohistochemical analysis revealed decreased expression of nuclear factor-kappa B (NF-κB) p65 in FFXHL-treated CIA rat joints. In vitro experiments demonstrated FFXHL's ability to decrease protein secretion of IL-1β and IL-6, suppress mRNA expression of matrix metalloproteinases (MMP) -3, -9, and -13, reduce reactive oxygen species (ROS) levels, and inhibit NF-κB p65 translocation in TNF-α stimulated MH7Acells. FFXHL also suppressed protein levels of extracellular signal-regulated kinase (ERK), c-Jun Nterminal kinase (JNK), p38 MAP kinase (p38), protein kinase B (Akt), p65, inhibitor of kappa B kinase α/β (IKKα/β), Toll-like receptor 4 (TLR4), and myeloid differentiation primary response 88 (MyD88) induced by TNF-α in MH7A cells. The findings imply that FFXHL exhibits significant anti-inflammatory and antiarthritic effects in both CIA rat models and TNF-α-induced MH7A cells. The potential mechanism involves the inactivation of TLR4/MyD88, mitogen-activated protein kinases (MAPKs), NF-κB, and Akt pathways by FFXHL.

Inhibition of N-myristoyltransferase activity promotes androgen receptor degradation in prostate cancer.

Even though prostate cancer (PCa) patients initially respond to androgen deprivation therapy, some will eventually develop castration resistant prostate cancer (CRPC). Androgen receptor (AR) mediated cell signaling is a major driver in the progression of CRPC while only a fraction of PCa becomes AR negative. This study aimed to understand the regulation of AR levels by N-myristoyltransferase in PCa cells. Two enantiomers, (1S,2S)- d-NMAPPD and (1R,2R)- d-NMAPPD (LCL4), were characterized by various methods (1 H and 13 C NMR, UHPLC, high-resolution mass spectra, circular dichroism) and evaluated for the ability to bind to N-myristoyltransferase 1 (NMT1) using computational docking analysis. structure-activity relationship analysis of these compounds led to the synthesis of (1R,2R)-LCL204 and evaluation as a potential NMT1 inhibitor utilizing the purified full length NMT1 enzyme. The NMT inhibitory activity wase determined by Click chemistry and immunoblotting. Regulation of NMT1 on tumor growth was evaluated in a xenograft tumor model. (1R,2R)- d-NMAPPD, but not its enantiomer (1S,2S)- d-NMAPPD, inhibited NMT1 activity and reduced AR protein levels. (1R,2R)-LCL204, a derivative of (1R,2R)- d-NMAPPD, inhibited global protein myristoylation. It also suppressed protein levels, nuclear translocation, and transcriptional activity of AR full-length or variants in PCa cells. This was due to enhanced ubiquitin and proteasome-mediated degradation of AR. Knockdown of NMT1 levels inhibited tumor growth and proliferation of cancer cells. Inhibitory efficacy on N-myristoyltransferase activity by d-NMAPPD is stereospecific. (1R,2R)-LCL204 reduced global N-myristoylation and androgen receptor protein levels at low micromolar concentrations in prostate cancer cells. pharmacological inhibition of NMT1 enhances ubiquitin-mediated proteasome degradation of AR. This study illustrates a novel function of N-myristoyltransferase and provides a potential strategy for treatment of CRPC.

Secreted protease PRSS35 suppresses hepatocellular carcinoma by disabling CXCL2-mediated neutrophil extracellular traps

Hepatocytes function largely through the secretion of proteins that regulate cell proliferation, metabolism, and intercellular communications. During the progression of hepatocellular carcinoma (HCC), the hepatocyte secretome changes dynamically as both a consequence and a causative factor in tumorigenesis, although the full scope of secreted protein function in this process remains unclear. Here, we show that the secreted pseudo serine protease PRSS35 functions as a tumor suppressor in HCC. Mechanistically, we demonstrate that active PRSS35 is processed via cleavage by proprotein convertases. Active PRSS35 then suppresses protein levels of CXCL2 through targeted cleavage of tandem lysine (KK) recognition motif. Consequently, CXCL2 degradation attenuates neutrophil recruitment to tumors and formation of neutrophil extracellular traps, ultimately suppressing HCC progression. These findings expand our understanding of the hepatocyte secretome’s role in cancer development while providing a basis for the clinical translation of PRRS35 as a therapeutic target or diagnostic biomarker.

Protective Effects of Topical Administration of Laminarin in Oxazolone-Induced Atopic Dermatitis-like Skin Lesions.

Laminarin is a polysaccharide isolated from brown marine algae and has a wide range of bioactivities, including immunoregulatory and anti-inflammatory properties. However, the effects of laminarin on atopic dermatitis have not been demonstrated. This study investigated the potential effects of topical administration of laminarin using a Balb/c mouse model of oxazolone-induced atopic dermatitis-like skin lesions. Our results showed that topical administration of laminarin to the ear of the mice improved the severity of the dermatitis, including swelling. Histological analysis revealed that topical laminarin significantly decreased the thickening of the epidermis and dermis and the infiltration of mast cells in the skin lesion. Serum immunoglobulin E levels were also significantly decreased by topical laminarin. Additionally, topical laminarin significantly suppressed protein levels of oxazolone-induced proinflammatory cytokines, such as interleukin-1β, tumor necrosis factor-α, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1α in the skin lesion. These results indicate that topical administration of laminarin can alleviate oxazolone-induced atopic dermatitis by inhibiting hyperproduction of IgE, mast cell infiltration, and expressions of proinflammatory cytokines. Based on these findings, we propose that laminarin can be a useful candidate for the treatment of atopic dermatitis.

CircCBFB is a mediator of hepatocellular carcinoma cell autophagy and proliferation through miR-424-5p/ATG14 axis.

This study aims to investigate the role of circCBFB in hepatocellular carcinoma (HCC) cell proliferation and autophagy. qRT-PCR and Western blotting analyses quantified the expression levels of circCBFB, miR-424-5p, and ATG14 in HCC tissues and/or HCC cell lines. After transfection with pcDNA3.1-CircCBFB, sh-CircCBFB, miR-424-5p mimic, miR-424-5p inhibitor, pcDNA3.1-ATG14, sh-ATG14, sh-CircCBFB + miR-424-5p inhibitor, pcDNA3.1-CircCBFB + miR-424-5p mimic, sh-CircCBFB + pcDNA3.1-ATG14, or pcDNA3.1-CircCBFB + sh-ATG14, the proliferation, cell cycle, and apoptosis of Huh-7 and HCCLM3 cells were detected, respectively, through MTT assay and flow cytometry. Western blotting measured the expression levels of ATG14 and autophagy-related proteins (LC3-ΙΙ/LC3-Ι, Beclin1, and p62). The interactions among circCBFB, miR-424-5p, and ATG14 were identified through RNA fluorescence in situ hybridization and RNA immunoprecipitation. In HCC tissues, circCBFB and ATG14 were highly expressed, and miR-424-5p expression was downregulated. Transfection of pcDNA3.1-CircCBFB, miR-424-5p inhibitor, or pcDNA3.1-ATG14 into HCC cells facilitated HCC cell proliferation and autophagy, while suppressing cell apoptosis, evidenced by elevated cell viability, increased protein levels of autophagosome markers (LC3-ΙΙ/LC3-Ι and Beclin1), repressed apoptosis rate, and suppressed protein level of autophagy receptor p62. miR-424-5p was a target gene of circCBFB, and miR-424-5p negatively mediated ATG14. CircCBFB inhibits miR-424-5p and upregulates ATG14, thus promoting HCC cell proliferation and autophagy.

Emodin alleviates sepsis-mediated lung injury via inhibition and reduction of NF-kB and HMGB1 pathways mediated by SIRT1.

Inflammation plays an important role during sepsis, and excessive inflammation can result in organ damage, chronic inflammation, fibrosis, and scarring. The study aimed to investigate the specific mechanism of emodin by constructing in vivo and in vitro septic lung injury models via inhibition and reduction of NF-kB and high mobility group box 1 (HMGB1) pathways. A cecal ligation and puncture (CLP) model was built for adult male Sprague-Dawley rats. Concentrations of TNF-α, IL-1β, and IL-6 in bronchoalveolar lavage fluid were determined using commercially available ELISA kits. Hematoxylin and eosin staining was used for the right lung inferior lobes. Myeloperoxidase (MPO) activity of the lung tissue was detected by using the MPO kit. Murine alveolar epithelial cell line (MLE-12) cells were used for flow cytometry and Western blot to analyze the apoptosis rate and protein expression. Emodin significantly decreased CLP-induced cell apoptosis, upregulated expression of sirtuin 1 (SIRT1), and inhibited p-p65/p65 and HMGB1. In lipopolysaccharide (LPS) treated cell model, emodin treatment markedly decreased LPS-induced release of IL-1, IL-6, and tumor necrosis factor (TNF)-α, inhibited LPS-induced cell apoptosis and suppressed protein levels of P-P65/P65 and HMGB1. However, science of SIRT1 reversed the above effects by treatment of emodin. In summarize, this study found that emodin can alleviate sepsis-induced lung injury in vivo and in vitro through regulation of SIRT1.

Umbralisib/TGR-1202 As a Novel Dual PI3K/CK1 Inhibitor Has a Unique Therapeutic Role in Silencing Oncogenes in Aggressive Lymphomas

Introduction: A number of oncogenes have been shown to promote the pathogenesis and correlate with poor survival in aggressive lymphoma. For example, deregulation of C-MYC is prevalent in diffuse large B cell lymphoma (DLBCL), chromosome translocations involving C-MYC and BCL2 define “double hit lymphoma” (DHL), and chromosome translocation involving CCND1 is pathognomonic for mantle cell lymphoma (MCL). Despite impressive progress being made in the treatment of these aggressive lymphomas, the treatment options for patients with relapsed aggressive lymphoma, especially DHL, remain inadequate. Interestingly, translation of C-MYC, BCL2, CCND1, and a number of other oncogenes is highly sensitive to inhibition of the eukaryotic translation initiation factor 4F (eIF4F) (Manier et al., 2017; Wolfe et al., 2014), which is comprised of the eIF4E, eIF4A, and eIF4G subunits. However, inhibitors of eIF4F are currently not available for the clinic. eIF4F is negatively regulated by the eIF4E binding protein 1 (4E-BP1), which in the hypo-phosphorylated form sequesters eIF4E (Haghighat et al., 1995). To allow for robust initiation of translation in cancer cells 4E-BP1 is hyper-phosphorylated by upstream signals, such as mechanistic target of rapamycin (mTOR). Our recent results indicate that casein kinase 1 epsilon (CK1ε) positively regulate translation via phosphorylating4E-BP1 (Deng et al., 2016). There may be additional poorly understood signals regulating 4E-BP1. Although no CK1ε inhibitor has been developed for the clinic, we recently discovered that the PI3Kδ inhibitor umbralisib/TGR-1202 acts additionally to inhibit CK1ε. Given that TGR-1202 has demonstrated a favorable safety profile in clinical trials and is capable of targeting both PI3Kδ and CK1ε, the drug may be particularly valuable for the silencing of oncogenes in aggressive lymphoma. Our hypothesis is the following: If hyper-phosphorylation of 4E-BP1 serves as a nexus for upregulating oncogene translation, then co-targeting signals phosphorylating 4E-BP1, such as CK1ε and mTOR, may potently and synergistically silence oncogenes in aggressive lymphomas.Materials and Methods: Cytotoxicity was studied in lymphoma cell lines and using Cell TiterGlo (Promega®). Screen of drug synergy was performed between pairs of TGR-1202, mTOR inhibitors, proteasome inhibitors, and CK1 inhibitors. The Bliss additivism model was used to determine the expected inhibition of cell growth and the excess over Bliss (EOB) values. EOB values above 0 indicate synergy, with higher values indicating higher levels of synergy. Expression of oncogenes was studied by Western blot and qPCR. 4E-BP1 was studied by Western blot and by 4E-BP1 cap-binding assay using m7GTP Sepharose beads. Translation was determined using a bicistronic reporter. Drug studies were validated by gene knockout of expected molecular targets such as CK1ε and PI3Kδ using CRISPR/Cas9. To further investigate the global effects of targeting translation initiation, we are conducting in parallel proteomic and RNA-Seq studies in 3 cell lines representing DLBCL, DHL, and MCL. Furthermore, the mechanism will be validated by rescuing experiments through over-expression of eIF4E, MYC, or CCND1. The efficacy of TGR-1202-containing regimens is being investigated in xenograft mouse models of MCL.Results: We investigated the combinatorial effect of TGR-1202 and the proteasome inhibitor carfilzomib. The combination of TGR-1202 and carfilzomib (TC) was highly synergistic in mantle cell lymphoma and double hit lymphoma cell lines (Figure 1A). TC synergistically inhibited phosphorylation of 4E-BP1 at the Ser65 in both MCL and DHL (Figure1B). The TC combination synergistically produced cleavage of poly-ADP ribose polymerase (PARP), indicating apoptosis as its mechanism (Figure 1C). TC reduced the protein expression levels of several oncogenes responsible for malignancies such as c-Myc, cyclin D1, and Bcl-2. In contrast, this combination had no significant effect on the mRNA level of c-Myc and cyclin D1 (Figure 1D).Conclusion: A novel therapeutic strategy can be developed by combining umbralisib/TGR-1202 and the proteasome inhibitor carfilzomib for the treatment of DLBCL, DHL, and MCL. The combination induces apoptosis by inhibiting the phosphorylation of 4E-BP1, leading to translational silencing and suppressed protein levels of c-Myc, cyclin D1, and Bcl-2. [Display omitted] DisclosuresAli:Onconova Therapeutics: Consultancy; Kura Oncology: Consultancy. O'Connor:Celgene: Honoraria, Research Funding; Trillium Therapeutics: Research Funding.

Short-term administration of C. aronia stimulates insulin signaling, suppresses fatty acids metabolism, and increases glucose uptake and utilization in the hearts of healthy rats.

This study evaluated the effect of Crataegus aronia (C. aronia) aqueous extract on cardiac substrate utilization and insulin signaling in adult male healthy Wistar rats. Rats (n=18/group) were either administered normal saline (vehicle) or treated with C. aronia aqueous extract (200mg/kg) for 7days, daily. Fasting plasma glucose and insulin levels were not significantly changed in C. aronia-treated rats but were significantly reduced after both the intraperitoneal glucose or insulin tolerance tests. Besides, C. aronia significantly increased the left ventricular (LV) activities of phosphofructokinase (PFK) and pyruvate dehydrogenase (PDH), two markers of glycolysis and glucose oxidation, respectively, and suppressed the levels of pyruvate dehydrogenase kinase 4 (PDK4), an inhibitor of PDH. Concomitantly, it significantly reduced the LV levels of carnitine palmitoyltransferase 1 (CPT1) and PPARα, two markers of fatty acid (FAs) oxidations. Under basal and insulin stimulation, C. aronia aqueous extract boosted insulin signaling in the LV of rats by increasing the protein levels of p-IRS (Tyr612) and p-Akt (Ser473) and suppressing protein levels of p-mTOR (Ser 2448) and p-IRS (Ser307). In parallel, C. aronia also increased the protein levels of GLUT-4 in the membrane fraction of the treated LVs. All these effects were also associated with a significant increase in AMPK activity (phosphorylation at Thr172), a major energy modulator that stimulates glucose utilization. In conclusion, short-term administration of C. aronia aqueous extract shifts the cardiac metabolism toward glucose utilization, thus making this plant a potential therapeutic medication in cardiac disorders with impaired metabolism.

Molecular Diversity of Glutamatergic and GABAergic Synapses from Multiplexed Fluorescence Imaging.

Neuronal synapses contain hundreds of different protein species important for regulating signal transmission. Characterizing differential expression profiles of proteins within synapses in distinct regions of the brain has revealed a high degree of synaptic diversity defined by unique molecular organization. Multiplexed imaging of in vitro rat primary hippocampal culture models at single synapse resolution offers new opportunities for exploring synaptic reorganization in response to chemical and genetic perturbations. Here, we combine 12-color multiplexed fluorescence imaging with quantitative image analysis and machine learning to identify novel synaptic subtypes within excitatory and inhibitory synapses based on the expression profiles of major synaptic components. We characterize differences in the correlated expression of proteins within these subtypes and we examine how the distribution of these synapses is modified following induction of synaptic plasticity. Under chronic suppression of neuronal activity, phenotypic characterization revealed coordinated increases in both excitatory and inhibitory protein levels without changes in the distribution of synaptic subtypes, suggesting concerted events targeting glutamatergic and GABAergic synapses. Our results offer molecular insight into the mechanisms of synaptic plasticity.

Hypoxic naked mole-rat brains use microRNA to coordinate hypometabolic fuels and neuroprotective defenses.

Naked mole-rats are among the mammalian champions of hypoxia tolerance. They evolved adaptations centered around reducing metabolic rate to overcome the challenges experienced in their underground burrows. In this study, we used next-generation sequencing to investigate one of the factors likely supporting hypoxia tolerance in naked mole-rat brains, posttranscriptional microRNAs (miRNAs). Of the 212 conserved miRNAs identified using small RNA sequencing, 18 displayed significant differential expression during hypoxia. Bioinformatic enrichment revealed that hypoxia-mediated miRNAs were suppressing energy expensive processes including de novo protein translation and cellular proliferation. This suppression occurred alongside the activation of neuroprotective and neuroinflammatory pathways, and the induction of central signal transduction pathways including HIF-1α and NFκB via miR-335, miR-101, and miR-155. MiRNAs also coordinated anaerobic glycolytic fuel sources, where hypoxia-upregulated miR-365 likely suppressed protein levels of ketohexokinase, the enzyme responsible for catalyzing the first committed step of fructose catabolism. This was further supported by a hypoxia-mediated reduction in glucose transporter 5 proteins that import fructose into the cell. Yet, messenger RNA and protein levels of lactate dehydrogenase, which converts pyruvate to lactate in the absence of oxygen, were elevated during hypoxia. Together, this demonstrated the induction of anaerobic glycolysis despite a lack of reliance on fructose as the primary fuel source, suggesting that hypoxic brains are metabolically different than anoxic naked mole-rat brains that were previously found to shift to fructose-based glycolysis. Our findings contribute to the growing body of oxygen-responsive miRNAs "OxymiRs" that facilitate natural miRNA-mediated mechanisms for successful hypoxic exposures.

Salidroside protects against diabetes mellitus-induced kidney injury and renal fibrosis by attenuating TGF-β1 and Wnt1/3a/β-catenin signalling.

This study evaluated if the nephroprotective effect of Salidroside in type 1 diabetes mellitus (T1DM) involves modulation of Wnt/β-catenin signalling pathways. Control or Streptozotocin (STZ, 50mg/kg, iv)-induced T1DM adult male Wister rats were treated with the vehicle and Salidroside (100mg/kg, orally) for 8weeks daily. As compared to T1DM-induced rats, Salidroside improved kidney structure, reduced urinary protein and albumin level, increased creatinine clearance, and suppressed renal fibrosis. It also decreased mRNA and protein levels of Wnt1, Wnt3, and TGF-β1, phosphorylation of Smad-3, total and nuclear levels of β-catenin, and levels and activities of cleaved caspase-3. Concomitantly, Salidroside significantly increased the levels of p-β-catenin (Ser33/37 /Thr41 ) and suppressed protein levels of Axin-2, fibronectin, and, mRNA and protein levels of collagen IIIa, the main targets of β-catenin. In both control and T1DM rats, Salidroside significantly lowered fasting glucose levels and reduced renal levels of reactive oxygen species (ROS) p-and GS3Kβ (Ser9) but significantly increased levels of SOD and GSH. In conclusion, Salidroside protected the kidney of rats against T1DM-induced injury and fibrosis by activating GS3Kβ-induced inhibition of Wnt1/Wnt3a β-catenin. This was associated with hypoglycaemic and antioxidant effects.

Targeting Aspartate Beta-Hydroxylase with the Small Molecule Inhibitor MO-I-1182 Suppresses Cholangiocarcinoma Metastasis.

Cholangiocarcinoma is a devastating disease with a 2% 5-year survival if the disease has spread outside the liver. The enzyme aspartate beta-hydroxylase (ASPH) has been demonstrated to be highly expressed in cholangiocarcinoma but not in normal bile ducts and found to stimulate tumor cell migration. In addition, it was found that targeting ASPH inhibits cholangiocarcinoma malignant progression. However, it is not clear whether targeting ASPH with the small molecule inhibitor MO-I-1182 suppresses cholangiocarcinoma metastasis. The current study aims to study the efficacy of MO-I-1182 in suppressing cholangiocarcinoma metastasis. The analysis was performed in vitro and in vivo with a preclinical animal model by using molecular and biochemical strategies to regulate ASPH expression and function. Knockdown of ASPH substantially inhibited cell migration and invasion in two human cholangiocarcinoma cell lines. Targeting ASPH with a small molecule inhibitor suppressed cholangiocarcinoma progression. Molecular mechanism studies demonstrated that knockdown of ASPH subsequently suppressed protein levels of the matrix metalloproteinases. The ASPH knockdown experiments suggest that this enzyme may modulate cholangiocarcinoma metastasis by regulating matrix metalloproteinases expression. Furthermore, using an ASPH inhibitor in a rat cholangiocarcinoma intrahepatic model established with BED-Neu-CL#24 cholangiocarcinoma cells, it was found that targeting ASPH inhibited intrahepatic cholangiocarcinoma metastasis and downstream expression of the matrix metalloproteinases. ASPH may modulate cholangiocarcinoma metastasis via matrix metalloproteinases expression. Taken together, targeting ASPH function may inhibit intrahepatic cholangiocarcinoma metastasis and improve survival.

Selenoproteins and their emerging roles in signaling pathways

The functional activity of selenoproteins has a wide range of effects on complex pathogenetic processes, including teratogenesis, immuno-inflammatory, neurodegenerative. Being active participants and promoters of many signaling pathways, selenoproteins support the lively interest of a wide scientific community. This review is devoted to the analysis of recent data describing the participation of selenoproteins in various molecular interactions mediating important signaling pathways. Data processing was carried out by the method of complex analysis. For convenience, all selenoproteins were divided into groups depending on their location and function. Among the group of selenoproteins of the ER membrane, selenoprotein N affects the absorption of Ca2+ by the endoplasmic reticulum mediated by oxidoreductin (ERO1), a key player in the CHOP/ERO1 branch, a pathogenic mechanism that causes myopathy. Another selenoprotein of the ER membrane selenoprotein K binding to the DHHC6 protein affects the IP3R receptor that regulates Ca2+ flux. Selenoprotein K is able to affect another protein of the endoplasmic reticulum CHERP, also appearing in Ca2+ transport. Selenoprotein S, associated with the lumen of ER, is able to influence the VCP protein, which ensures the incorporation of selenoprotein K into the ER membrane. Selenoprotein M, as an ER lumen protein, affects the phosphorylation of STAT3 by leptin, which confirms that Sel M is a positive regulator of leptin signaling. Selenoprotein S also related to luminal selenoproteins ER is a modulator of the IRE1α-sXBP1 signaling pathway. Nuclear selenoprotein H will directly affect the suppressor of malignant tumours, p53 protein, the activation of which increases with Sel H deficiency. The same selenoprotein is involved in redox regulation. Among the cytoplasmic selenoproteins, abundant investigations are devoted to SelP, which affects the PI3K/Akt/Erk signaling pathway during ischemia/reperfusion, is transported into the myoblasts through the plasmalemma after binding to the apoER2 receptor, and into the neurons to the megaline receptor and in general, selenoprotein P plays the role of a pool that stores the necessary trace element and releases it, if necessary, for vital selenoproteins. The thioredoxin reductase family plays a key role in the invasion and metastasis of salivary adenoid cystic carcinoma through the influence on the TGF-β-Akt/GSK-3β pathway during epithelial-mesenchymal transition. The deletion of thioredoxin reductase 1 affects the levels of messengers of the Wnt/β-catenin signaling pathway. No less studied is the glutathione peroxidase group, of which GPX3 is able to inhibit signaling in the Wnt/β-catenin pathway and thereby inhibit thyroid metastasis, as well as suppress protein levels in the PI3K/Akt/c-fos pathway. A key observation is that in cases of carcinogenesis, a decrease in GPX3 and its hypermethylation are almost always found. Among deiodinases, deiodinase 3 acts as a promoter of the oncogenes BRAF, MEK or p38, while stimulating a decrease in the expression of cyclin D1. The dependence of the level of deiodinase 3 on the Hedgehog (SHH) signaling pathway is also noted. Methionine sulfoxide reductase A can compete for the uptake of ubiquitin, reduce p38, JNK and ERK promoters of the MAPK signaling pathway; methionine sulfoxide reductase B1 suppresses MAPK signaling messengers, and also increases PARP and caspase 3.

Withaferin A inhibits expression of ataxia telangiectasia and Rad3-related kinase and enhances sensitivity of human breast cancer cells to cisplatin.

Ataxia telangiectasia and Rad3-related (ATR) is a serine/threonine-specific kinase that plays an important role in the maintenance of genomic integrity. In this study, we investigated the role of ATR in cell-cycle arrest by withaferin A (WA), a cancer preventative steroidal lactone derived from Withania somnifera plant abundant in India and surrounding countries. The WA treatment decreased the viability of MCF-7, MDA-MB-231, and SUM159 cells. Exposure of breast cancer cells to WA also resulted in suppression of protein level as well as phosphorylation of ATR and its downstream effector kinase (checkpoint kinase 1; CHK1). Both transcriptional and posttranscriptional mechanisms were involved in the WA-mediated downregulation of ATR protein. Downregulation of ATR protein expression resulting from WA exposure was not attenuated by overexpression of manganese superoxide dismutase. In contrast, the overexpression of CHK1 attenuated WA-mediated G2 /M arrest and augmented S10 phosphorylation of histone H3, a marker of mitotic arrest. The protein level of ATR was lowered by about 50% in breast tumors of WA-treated mouse mammary tumor virus-neu mice when compared with vehicle-treated controls but the difference was not significant due to small sample size. WA treatment sensitized MDA-MB-231 and SUM159 cells to growth inhibition and apoptosis induction by cisplatin. Cisplatin treatment resulted in increased autophosphorylation of ATR (T1989) and CHK1 (S345) phosphorylation that was markedly suppressed in the presence of WA. These results indicate that WA is an inhibitor of ATR in human breast cancer cells.

Effects of β-carotene on oxazolone-induced atopic dermatitis in hairless mice.

Skin acts as a barrier, which protects internal tissues and promotes moisture retention. Atopic dermatitis (AD) is an inflammatory skin disease associated with a variety of genetic and environmental factors that involve helper T cells. β-Carotene (provitamin A) exhibits antioxidant activity and activates the immune system. However, it is not clear whether inflammation in AD skin is improved by posttreatment with β-carotene. In the current study, we investigated the effects of β-carotene on the skin of hairless mice with oxazolone-induced inflammation/oedema (Ox-AD mice). We found that skin inflammation was significantly reduced by oral administration of β-carotene. In addition, treatment with β-carotene suppressed protein levels of TNF-α, IL-1β and MCP-1, as well as mRNA expression associated with IL-1β, IL-6, IL-4 and Par-2 in skin tissues. Furthermore, the mRNA and protein levels of filaggrin, a structural protein in the epidermal stratum corneum, were elevated by β-carotene administration as compared with Ox-AD mice. β-Carotene significantly reduced the activity of proMMP-9, but not proMMP-2. These results suggest that in Ox-AD mice, β-carotene improves skin inflammation by suppressing the expression of inflammatory factors, promoting filaggrin expression and reducing MMP-9 activity. β-Carotene is a potent anti-inflammatory agent that improves the barrier functions of AD skin.

CD44 Promotes Migration and Invasion of Docetaxel-Resistant Prostate Cancer Cells Likely via Induction of Hippo-Yap Signaling.

Patients receiving docetaxel developed a drug resistance within a few months. We generated docetaxel-resistant PC/DX25 and DU/DX50 CRPC cells from PC-3 and DU-145 PCa cells, respectively. We investigated the mechanism behind why PC/DX25 and DU/DX50 cells exhibited higher migration and invasion ability. Transwell assays were used to measure the migration and invasion of PCa cell. Fluorescence activated cell sorter (FACS) analysis was used to determine the population of cancer stem cell (CSC)-like cell. Micro-Western Array (MWA) was used to study the changes of the protein profile. FACS analysis revealed that PC/DX25 cells and DU/DX50 cells contain higher CD44+ population. MWA and Western blotting assay revealed that protein expression of CD44, YAP, CYR61, CTGF, phospho-ERK1/2 T202/Y204, ERK and vimentin was elevated in PC/DX25 cells. Knockdown of CD44 or YAP suppressed migration and invasion of PC/DX25 and DU/DX50 cells. Knockdown of CD44 decreased expression of YAP, CTGF and CYR61 but increased phosphorylation of S127 on YAP. CD44 knockdown also suppressed protein level of AKT, phospho-AKT T308, phospho-ERK1/2 T202/Y204 and vimentin. CD44 promotes migration and invasion of docetaxel-resistant PCa cells probably via induction of Hippo-Yap signaling pathway and CD44/YAP pathway may be a therapeutic target for docetaxel-resistant PCa.