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Abstract: Myocardial ischemia-reperfusion (MIR)-induced arrhythmia remains a major cause of death in patients with cardiovascular diseases. The reduction of Cx43 has been known as a major inducer of arrhythmias after MIR, but the reason for the reduction of Cx43 remains largely unknown. The aim of this study was to find the key mechanism underlying the reduction of Cx43 after MIR and to screen out an herbal extract to attenuate arrhythmia after MIR. The differentially expressed genes in the peripheral blood mononuclear cell (PBMCs) after MIR were analyzed using the data from several gene expression omnibus data sets, followed by the identification in PBMCs and the serum of patients with myocardial infarction. Tumor necrosis factor superfamily protein 14 (TNFSF14) was increased in PBMCs and the serum of patients, which might be associated with the injury after MIR. The toxic effects of TNFSF14 on cardiomyocytes were investigated in vitro . Valtrate was screened out from several herbal extracts. Its protection against TNFSF14-induced injury was evaluated in cardiomyocytes and animal models with MIR. Recombinant TNFSF14 protein not only suppressed the viability of cardiomyocytes but also decreased Cx43 by stimulating the receptor LTβR. LTβR induces the competitive binding of MAX to MGA rather than the transcriptional factor c-Myc, thereby suppressing c-Myc-mediated transcription of Cx43. Valtrate promoted the N-linked glycosylation modification of LTβR, which reversed TNFSF14-induced reduction of Cx43 and attenuated arrhythmia after MIR. In all, valtrate suppresses TNFSF14-induced reduction of Cx43, thereby attenuating arrhythmia after MIR., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Currently, chronic hepatitis B virus infection is still one of the most serious public health problems in the world. Though current strategies are effective in controlling infection and slowing down the disease process, it remains a big challenge to achieve a functional cure for chronic hepatitis B in a majority of patients due to the inability to clear the cccDNA pool. The mammalian target of rapamycin (mTOR) integrates nutrition, energy, growth factors, and other extracellular signals, participating in gene transcription, protein translation, ribosome synthesis, and other biological processes. Additionally, mTOR plays an extremely important role in cell growth, apoptosis, autophagy, and metabolism. More and more evidence show that HBV infection can activate the mTOR pathway, suggesting that HBV uses or hijacks the mTOR pathway to facilitate its own replication. Therefore, mTOR signaling pathway may be a key target for controlling HBV infection. However, the role of the central cytokine mTOR in the pathogenesis of HBV infection has not yet been systematically addressed. Notably, mTOR is commonly activated in hepatocellular carcinoma, which can progress from chronic hepatitis B. This review systematically summarizes the role of mTOR in the life cycle of HBV and its impact on the clinical progression of HBV infection., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Congenital heart disease (CHD) is a type of major defect that occurs during embryonic development. Although significant advances have been made in the treatment of CHD, its etiology and molecular mechanism remain unclear. To identify the critical role of SUMOylation in cardiac development, we generated SENP3 knockout mice and showed that SENP3 knockout mice die on embryonic day 8.5 with an open neural tube and reversed left-right cardiac asymmetry. Moreover, SENP3 knockout promoted apoptosis and senescence of H9C2 cells. Further studies showed that Nodal, a critical gene that forms left-right asymmetry, is regulated by SENP3 and that SENP3 regulates cell apoptosis and senescence in a Nodal-dependent manner. Furthermore, Nodal was hyper-SUMOylated after SENP3 knockout, and SUMOylation of Nodal inhibited its ubiquitination and ubiquitin-proteasome degradation pathway. Nodal overexpression enhanced cell apoptosis and senescence; however, the mutation at the SUMOylation site of Nodal reversed its effect on the apoptosis and senescence of H9C2 cells. More importantly, the SENP3-Nodal axis regulates cell senescence by inducing cell autophagy. These results suggest that the SENP3-Nodal signaling axis regulates cardiac senescence-autophagy homeostasis, which in turn affects cardiac development and results in the occurrence of CHD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The thymus, a site to culture the naïve T lymphocytes, is susceptible to atrophy or involution due to aging, inflammation, and oxidation. Epigallocatechin-3-gallate (EGCG) has been proven to possess anti-inflammatory, antioxidant, and antitumor activity. Here, we investigate the effects of EGCG on thymic involution induced by lipopolysaccharide (LPS), an endotoxin derived from Gram-negative bacteria. The methodology included an in vivo experiment on female Kunming mice exposed to LPS and EGCG. Morphological assessment of thymic involution, immunohistochemical detection, and thymocyte subsets analysis by flow cytometry were further carried out to evaluate the potential role of EGCG on the thymus. As a result, we found that EGCG alleviated LPS-induced thymic atrophy, increased mitochondrial membrane potential and superoxide dismutase levels, and decreased malondialdehyde and reactive oxygen species levels. In addition, EGCG pre-supplement restored the ratio of thymocyte subsets, the expression of autoimmune regulator, sex-determining region Y-box 2, and Nanog homebox, and reduced the number of senescent cells and collagen fiber deposition. Western blotting results indicated that EGCG treatment elevated LPS-induced decrease in pAMPK, Sirt1 protein expression. Collectively, EGCG relieved thymus architecture and function damaged by LPS via regulation of AMPK/Sirt1 signaling pathway. Our findings may provide a new strategy on protection of thymus from involution caused by LPS by using EGCG. And EGCG might be considered as a potential agent for the prevention and treatment of thymic involution., (© 2024 The Societies and John Wiley & Sons Australia, Ltd.)

Objective: To explore the key targets and signaling pathways in the therapeutic mechanism of Semiliquidambar cathayensis Chang (SC) root against pancreatic cancer network pharmacology and molecular docking studies and cell experiments., Methods: The targets of SC and pancreatic cancer were predicted using the network pharmacological database, the protein-protein interaction network was constructed, and pathways, functional enrichment and molecular docking analyses were performed. CCK-8 assay was used to test the inhibitory effect of the aqueous extract of SC root on 8 cancer cell lines, and its effects on invasion, migration, proliferation, and apoptosis of pancreatic cancer cells were evaluated. Western blotting was performed to verify the results of network pharmacology analysis., Results: We identified a total of 18 active components in SC, which regulated 21 potential key targets in pancreatic cancer. GO and KEGG pathway enrichment analyses showed that these targets were involved mainly in the biological processes including protein phosphorylation, signal transduction, and apoptosis and participated in cancer signaling and PI3K-Akt signaling pathways. Among the 8 cancer cell lines, The aqueous extract of SC root produced the most obvious inhibitory effect in pancreatic cancer cells, and significantly inhibited the invasion, migration, and proliferation and promoted apoptosis of pancreatic cancer Panc-1 cells ( P < 0.05). Western blotting confirmed that SC significantly inhibited the phosphorylation levels of PI3K and AKT in Panc-1 cells ( P < 0.001)., Conclusion: The therapeutic effect of SC root against pancreatic cancer effects is mediated by its multiple components that act on different targets and pathways including the PI3K-Akt pathway.

Spleen tyrosine kinase (SYK) is a non-receptor cytoplasmic kinase. Due to its pivotal role in B cell receptor and Fc-receptor signalling, inhibition of SYK has been a target of interest in a variety of diseases. Herein, we report the use of structure-based drug design to discover a series of potent macrocyclic inhibitors of SYK, with excellent kinome selectivity and in vitro metabolic stability. We were able to remove hERG inhibition through the optimization of physical properties, and utilized a pro-drug strategy to address permeability challenges., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Cell signaling is a complex process. The faithful transduction of information into specific cellular actions depends on the synergistic effects of many regulatory molecules, nurtured by their strict spatiotemporal regulation. Over the years, we have gained copious insights into the subcellular architecture supporting this spatiotemporal control, including the roles of membrane-bound organelles and various signaling nanodomains. Recently, liquid-liquid phase separation (LLPS) has been recognized as another potentially ubiquitous framework for organizing signaling molecules with high specificity and precise spatiotemporal control in cells. Here, we review the pervasive role of LLPS in signal transduction, highlighting several key pathways that intersect with LLPS, including examples in which LLPS is controlled by signaling events. We also examine how LLPS orchestrates signaling by compartmentalizing signaling molecules, amplifying signals non-linearly, and moderating signaling dynamics. We focus on the specific molecules that drive LLPS and highlight the known functional and pathological consequences of LLPS in each pathway., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

In this study, we describe a new rat model of vertebral inflammation-induced caudal intervertebral disc degeneration (VI-IVDD), in which IVD structure was not damaged and controllable segment and speed degeneration was achieved. VI-IVDD model was obtained by placing lipopolysaccharide (LPS) in the caudal vertebral bodies of rats. Rat experimental groups were set as follows: normal control group, group with a hole drilled in the middle of vertebral body and not filled with LPS (Blank group), group with a hole drilled in the middle of vertebral body and filled with LPS (Mid group), and group with hole drilled in the vertebral body in proximity of IVD and filled with LPS (NIVD group). Radiological results of VI-IVDD rats showed a significant reduction in the intervertebral space height and decrease in MRI T2 signal intensity. Histological stainings also revealed that the more the nucleus pulposus and endplate degenerated, the more the annulus fibrosus structure appeared disorganized. Immunohistochemistry analysis demonstrated that the expression of Aggrecan and collagen-II decreased, whereas that of MMP-3 increased in Mid and NIVD groups. Abundant local production of pro-inflammatory cytokines was detected together with increased infiltration of M1 macrophages in Mid and NIVD groups. Apoptosis ratio remarkably enhanced in Mid and NIVD groups. Interestingly, we found a strong activation of the cyclic GMP-AMP synthase /stimulator of interferon gene signalling pathway, which is strictly related to inflammatory and degenerative diseases. In this study, we generated a new, reliable and reproducible IVDD rat model, in which controllable segment and speed degeneration was achieved., (© 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Gastric cancer is one of the most common malignant cancers globally. Chemotherapy resistance remains a major obstacle in the treatment of gastric cancer, and the molecular mechanisms underlying drug resistance are still not well understood. We previously reported that Zipper interacting protein kinase (ZIPK), also known as death-associated protein kinase3, exerts an oncogenic effect on gastric cancer via activation of Akt/NF-κB signaling and promotion of stemness. Here, we explored the roles of ZIPK in cisplatin resistance. We report that ZIPK enhances cell proliferation and invasion and reduces the antitumor activity of cisplatin in gastric cancer. In addition, our western blot data suggest that ZIPK activated the IL-6/STAT3 signaling pathway. Furthermore, ZIPK increased the expression of IL-6 and multidrug-resistance genes. Using the STAT3 inhibitor stattic to block the IL-6/STAT3 signaling pathway strongly increased the sensitivity of ZIPK-expressed cells to cisplatin. In conclusion, ZIPK may play a role in cisplatin resistance through activation of the IL-6/ STAT3 signaling pathway. Inhibition of STAT3 in gastric cancer overexpressing ZIPK might have potential to improve the efficacy of cisplatin., (© 2021 The Authors. FEBS Open Bio published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

The aberrant expression of long noncoding RNA (lncRNA) taurine-upregulated gene 1 (TUG1) has been previously associated with myocardial ischemia-reperfusion injury (MIRI), but the underlying molecular mechanisms remain elusive. The current study aimed to clarify the functional role of TUG1/microRNA (miR)-340/histone deacetylase 4 (HDAC4)/β-catenin/glucose transporter type 1 (GLUT1) axes in MIRI. The database-based analyses performed predicted the downstream factors of lncRNA TUG1. In the MIRI mouse models and hypoxia/reoxygenation (H/R)-induced cardiomyocyte models, the expression of TUG1/miR-340/HDAC4/β-catenin/GLUT1 was manipulated to examine their effects on the infarction area, cardiomyocyte viability and apoptosis employing the Evans blue/TTC double staining, CCK-8 and TUNEL assays. Furthermore, the dual luciferase reporter and RIP assays verified the binding affinity of miR-340 to TUG1 and HDAC4. Subsequently, a negative correlation between miR-340 and TUG1 or HDAC4 expression was identified in myocardial tissues of MIRI mice and H/R-induced cardiomyocyte models, along with a positive correlation between TUG1 and HDAC4. Additionally, it was established that TUG1 bound to miR-340, and miR-340 targeted HDAC4. TUG1 upregulated HDAC4 expression, thereby promoting MIRI in the mouse models. HDAC4 was proven to repress the expression of β-catenin and its target gene GLUT1. Moreover, the in vivo experiments validated that the inhibition of TUG1/miR-340/HDAC4/β-catenin/GLUT1 axes alleviated MIRI in mice. Collectively, the current study uncovered the role of TUG1/miR-340/HDAC4/β-catenin/GLUT1 axes in MIRI mouse models and H/R-induced cardiomyocyte models which may be a potential therapeutic target for MIRI treatment., (© 2020 Federation of American Societies for Experimental Biology.)

Purpose: To screen for candidate hub genes associated with the effects of exercise on melanoma tumor tissues and to review the potential signaling pathways involved in this process using bioinformatics analysis., Methods: The GSE62628 expression profile was downloaded from Gene Expression Omnibus database. This data set contains 10 melanoma tumor tissues from two groups of exercise and nonexercise mice. The R software was utilized to identify differentially expressed genes between samples, and functional annotation and pathway analysis were performed. Results were visualized using Cytoscape software., Results: In total, 315 differentially expressed genes were obtained, including 294 upregulated and 21 downregulated genes. The functional analysis showed that these genes were mainly enriched in immune response, inflammatory response, and positive regulation of the ERK1/2 cascade in biological process functional groups. The top 10 candidate hub genes were C3, Kng1, C3ar1, Ptafr, Fgg, Alb, Pf4, Orm1, Aldh3b1, and Apob. The pathway analysis of the most significant module identified from the protein-protein interaction network revealed that the complement and coagulation cascades, Staphylococcus aureus infection, cytokine-cytokine receptor interaction, chemokine signaling pathway and phagosome were mainly involved. C3, C3ar1, Kng1, Ptafr, and Fgg may be the critical genes in the complement and coagulation cascades pathway, and S. aureus in the infection pathway., Conclusions: Exercise may ameliorate the immune response and inflammatory response in melanoma tissue, and further studies exploring their relationships are warranted.

Exercise training is one of the major non-pharmacological treatments for hypertension. However, the central mechanism by which exercise training attenuates the hypertensive responses remains unclear. Irisin is a muscle-secreted cytokine derived from fibronectin type III domain containing 5 (FNDC5) that will be released into the circulation during exercise. We hypothesized that irisin may play a role in the blood pressure regulation by exercise. To examine the hypothesis, our study investigated the effect of irisin on hypertension and its central mechanism. The study was performed in spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto rats. We found that intravenous injection of irisin effectively reduced blood pressure, plasma norepinephrine, paraventricular nucleus (PVN) levels of neuronal activation, oxidative stress and inflammation in SHRs. Moreover, irisin activated nuclear factor E2-related factor-2 (Nrf2) and restored the imbalance of neurotransmitters in the PVN. Our study also found PVN knockdown of Nrf2 abolished the protective effects of irisin on hypertension. These findings demonstrate irisin can improve hypertension via Nrf2-mediated antioxidant in the PVN., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Post-traumatic stress disorder (PTSD) is a mental disease associated with the exposure of traumatic stress, and results in the structural and functional changes of hippocampus. Calcineurin (CaN), a calcium/calmodulin-regulated protein phosphatase ubiquitously expressed in brain, has a very important role in the fear extinction, neuronal structure and neuronal excitability. With CaN activation, its down target nuclear factor of activated T cells (NFATs) dephosphorylated and then translocated from the cytoplasm to the nucleus to affect neuronal function, resulting in the function changes of brain structure such as hippocampus. Increasing evidence has suggested that CaN/NFATs signaling are involved in the regulation of mental disorders like Alzheimer's disease, depression, while little is known about its effects on the molecular mechanisms on PTSD. This study seek to know the relationship between PTSD and CaN/NFATc4 pathway, and to detect whether CaN/NFATc4 pathway are involved in the hippocampus dysfunctions in a single-prolonged stress (SPS)-based rat model of PTSD. Our results have showed that after 4 days exposed to SPS, the protein expression of CaN up-regulated and the NFATc4 dephosphorylated and imported into the nucleus; while at the 7 and 14 day exposed to SPS, with the down-regulation of CaN, the expression of phosphorylate-NFATc4 increased. Our results show that CaN/NFATc4 pathway were involved in the development of PTSD model, which suggested that the changes of CaN/NFATc4 pathway may be one of the pathological molecular mechanism in the dysfunction of hippocampus in PTSD.

Substantial evidence has demonstrated that prenatal stress (PS) impairs spatial learning and memory in offspring. The neuron-specific protein kinase C gamma (PKCγ) has been proposed to be unique in spatial learning and memory. The present study proposes to determine whether hippocampal PKCγ is involved in the detrimental effects of PS on spatial learning and memory in offspring, and to further explore the effects of PS-induced PKCγ-dependent growth-associated protein 43 (GAP-43) and neurogranin (Ng) phosphorylation alteration on calcium/calmodulin-dependent protein kinase II (CaMKII) activation. Prenatal restraint stress models were established, and lentivirus-mediated overexpression of PKCγ in the hippocampal CA1 area was applied. The results demonstrated that PS impaired spatial learning acquisition and memory retrieval on the Morris Water Maze test, especially in juvenile female rats. Hippocampal PKCγ membrane translocation and cytosolic PKCγ levels were decreased in PS females. The expression of phosphorylated GAP-43 (p-GAP-43) and phosphorylated Ng (p-Ng), as well as phosphorylated CaMKII (p-CaMKII), was significantly reduced in the hippocampus of PS females. Overexpression of PKCγ in the hippocampal CA1 area recovered the ability of spatial learning and memory in PS female offspring. Furthermore, enhancing PKCγ reversed PS-induced membrane and cytosolic PKCγ reduction, and restored levels of GAP-43 and Ng phosphorylation, and CaMKII activation in the hippocampus. In conclusion, PS possibly decreases hippocampal PKCγ activity, resulting in a reduction of p-GAP-43 and p-Ng, which underlies insufficient CaMKII activation, thereby impairing spatial learning and memory., (Copyright © 2019 IBRO. Published by Elsevier Ltd. All rights reserved.)

The whitefly Bemisia tabaci is an important pest of worldwide agriculture. Previous work has shown that B. tabaci actively suppresses host plant defenses, but our knowledge of the specific mechanisms involved remains limited. Here we describe a B. tabaci salivary protein, the ferritin BtFer1, and its role in facilitating exploitation of host plants. We show that BtFer1 exhibits Fe2+ binding ability and ferroxidase activity, and that secretion of BtFer1 during B. tabaci feeding suppresses H2O2-generated oxidative signals in tomato (Solanum lycopersicum). Silencing BtFer1 enhanced the induction of the jasmonic acid (JA)-mediated defense signaling pathway in response to whitefly feeding, and led to increased callose deposition and the production of proteinase inhibitors that prevent whiteflies from continuously ingesting and digesting phloem sap. Consistent with these effects, silencing BtFer1 reduced whitefly survival on tomato but not on artificial diet. Using a JA-deficient spr2 mutant plant further showed that suppression of JA defenses by BtFer1 is sufficient to increase B. tabaci survival. Taken together, these results demonstrate that BtFer1 acts as an effector protein that mediates whitefly-tomato interactions. These findings represent an important step forward in understanding the molecular mechanisms by which whiteflies and other insect herbivores suppress host plant defenses., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

Fibroblast growth factor 21 (FGF21) plays an important role in the regulation of lipid and glucose metabolism. MS-275, as a class I-specific histone deacetylase (HDAC) inhibitor, has also been reported to affect energy metabolism. In this current study, we investigated the effects of MS-275 on hepatic FGF21 expression in vitro and in vivo and explored whether cAMP-responsive element-binding protein H (CREBH) was involved in the action of MS-275. Our results showed that MS-275 stimulated hepatic FGF21 mRNA and protein expressions in a dose- and time-dependent manner, as well as FGF21 secretion in primary mouse hepatocytes. Serum concentration and hepatic expression of FGF21 were elevated after injection of MS-275, along with increased expressions of genes involved in fatty acid oxidation and ketogenic production (peroxisome proliferator-activated receptor gammacoactivator1α, PGC-1α; carnitine palmitoyl-transferase 1a, CPT1a; 3-hydroxy-3-methylglutaryl-CoA synthase 2, Hmgcs2) as well as improved blood lipid profile. As a proved transcription factor of FGF21, the expression of CREBH was initiated by MS-275, with increased histone H3 lysine 18 acetylation (H3K18ac) signals and hepatocyte nuclear factor 4 alpha (HNF-4α) recruitment in CREBH promoter. Adenovirus-mediated knockdown of CREBH abolished MS-275-induced hepatic FGF21 and lipid metabolism-related gene expressions. These results suggest that MS-275 induces hepatic FGF21 by H3K18ac-mediated CREBH expression.

The dysfunction and mutual compensatory activation of RAF-MEK-ERK and PI3K-PDK1-AKT pathways have been demonstrated as the hallmarks in several primary and recurrent cancers. The strategy of concurrent blocking of these two pathways shows clinical merits on effective cancer therapy, such as combinatory treatments and dual-pathway inhibitors. Herein, we report a novel prototype of dual-pathway inhibitors by means of merging the core structural scaffolds of a MEK1 inhibitor and a PDK1 inhibitor. A library of 43 compounds that categorized into three series (Series I-III) was synthesized and tested for antitumor activity in lung cancer cells. The results from structure-activity relationship (SAR) analysis showed the following order of antitumor activity that 3-hydroxy-5-(phenylamino) indolone (Series III) > 3-alkenyl-5-(phenylamino) indolone (Series I) > 3-alkyl-5-(phenylamino) indolone (Series II). A lead compound 9za in Series III showed most potent antitumor activity with IC 50 value of 1.8 ± 0.8 µM in A549 cells. Moreover, antitumor mechanism study demonstrated that 9za exerted significant apoptotic effect, and cellular signal pathway analysis revealed the potent blockage of phosphorylation levels of ERK and AKT in RAF-MEK-ERK and PI3K-PDK1-AKT pathways, respectively. The results reported here provide robust experimental basis for the discovery and optimization of dual pathway agents for anti-lung cancer therapy., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Antimicrobial peptides (AMP) secreted by the granular glands of frog skin have been widely reported to exhibit strong bacteriostatic and bactericidal activities. Many of them have been documented with potent antiproliferative effects on multiple cancer cells, many studies also suggested that AMPs exert their functions via disrupting cell membranes. However, whether and how other cell death induction mechanism is involved in mammalian cancer cells has rarely been investigated. In this study, a novel AMP named Dermaseptin-PS1 was isolated and identified from Phyllomedusa sauvagei, it showed strong antimicrobial activities against three types of microorganisms. In vitro antiproliferative studies on human glioblastoma U-251 MG cells indicated that Dermaseptin-PS1 disrupted cell membranes at the concentrations of 10 -5  M and above, while the cell membrane integrity was not affected when concentrations were decreased to 10 -6  M or lower. Further examinations revealed that, at the relatively low concentration (10 -6  M), Dermaseptin-PS1 induced apoptosis through mitochondrial-related signal pathway in U-251 MG cells. Thus, for the first time, we report a novel frog skin derived AMP with anticancer property by distinct mechanisms, which largely depends on its concentration. Together, our study provides new insights into the mechanism-illustrated drug design and the optimisation of dose control for cancer treatment in clinic., (© 2018 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Introduction: The mechanism of tumorigenesis and metastasis of ovarian cancer has not yet been elucidated. This study aimed to investigate the role and molecular mechanism of cytosolic nonspecific dipeptidase 2 in tumorigenesis and metastasis., Methods: Cytosolic nonspecific dipeptidase 2 expression in human ovarian cancer tissues and cell lines was assessed with methyl thiazolyl tetrazolium (MTT), clone formation, and transwell assays performed to evaluate the ability of ovarian cancer cells to proliferate and migrate. Nude mice tumor formation experiments were also performed by subcutaneously injecting cells with stable cytosolic nonspecific dipeptidase 2 knockdown and control SKOV3 cells into BALB/c female nude mice to detect changes in PI3K/AKT pathway-related proteins by Western blotting., Results: Cytosolic nonspecific dipeptidase 2 was highly expressed in human ovarian cancer tissues, with its expression associated with pathological data, including ovarian cancer metastasis. A cytosolic nonspecific dipeptidase 2 stable knockdown or ectopic expression ovarian cancer cell model was established and demonstrated that cytosolic nonspecific dipeptidase 2 could promote the proliferation of ovarian cancer cells. Transwell cell migration and invasion assays confirmed that cytosolic nonspecific dipeptidase 2 enhanced cell metastasis in ovarian cancer. Furthermore, in vivo xenograft experiments demonstrated that cytosolic nonspecific dipeptidase 2 can promote the development and progression of ovarian cancer, increasing the expression of phosphorylated PI3K and AKT., Conclusions: Cytosolic nonspecific dipeptidase 2 promotes the occurrence and development of ovarian cancer through the PI3K/AKT signaling pathway.

Objective: Coronary microembolization (CME) is a common complication in percutaneous coronary intervention (PCI). Local myocardial inflammation caused by CME is the major cause of progressive cardiac dysfunction. High mobility group A1 (HMGA1)/nuclear factor-kappa B (NF-κB) signaling plays an important role in the development and progression of inflammation, but its role in CME remains unclear. This study evaluated the effect of HMGA1/NF-κB signaling on CME-induced myocardial inflammation and cardiac dysfunction., Methods: Forty Sprague-Dawley rats were randomly divided into four groups: sham, CME, CME + HMGA1 small interfering RNA (HMGA1 siRNA), and CME + scrambled siRNA (control siRNA) groups, with 10 animals each. The CME model group was established by clamping the ascending aorta and injecting microspheres through the left ventricular apex for embolization, and the sham group was established by injecting the same amount of normal saline. The HMGA1 siRNA group was injected with HMGA1 siRNA transfection complexes into the tail vein 72 h before CME modeling, and the control siRNA group was caudally injected with the same amount of scrambled siRNA 72 h before CME modeling. Twelve hours after the operation, cardiac function, serum c-troponin I level, and microinfarct size were examined. The levels of HMGA1, NF-κB p65, TNF-α, and IL-1β were detected., Results: Myocardial dysfunction, enhanced serum c-troponin I, and microinfarct were induced following CME. Moreover, CME induced an increased expression of HMGA1, NF-κB p65, TNF-α, and IL-1β. The HMGA1 siRNA reversed these effects by CME, while the scrambled siRNA had no effect., Conclusions: HMGA1/NF-κB signaling is involved in CME-induced myocardial inflammation. Inhibition of HMGA1/NF-κB signaling attenuated the CME-induced myocardial injury and improved cardiac function, suggesting a new potential target for the prevention and treatment of CME-induced myocardial injury., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Scope: This study aims to characterize the effect of fenugreek (Trigonella foenum-graecum) seed and its phytoceutical trigonelline in antimetabolic inflammation and ameliorating overproduction of very low density lipoprotein (VLDL) in insulin resistance., Methods and Results: Two groups of genetic hyperlipidemic mice generated by depletion of cAMP responsive element binding protein H (CREBH) are fed either a chow containing 2% fenugreek seed or vehicle for 7 weeks. Q-RT-PCR and immunoblotting analysis demonstrated that fenugreek seed containing diet inhibits hepatic SREBP-1c activation and the subsequent de novo lipogenesis by enhancing expression of insulin-inducible gene-1 (Insig-1) and gene-2 (Insig-2). mRNA expression of PPARα and its target genes that are involved in fatty acid β-oxidation are also upregulated in the fenugreek seed fed-mice which is accompanied by significantly reduced hepatic lipid accumulation and VLDL secretion, improved endoplasmic reticulum (ER) stress, and ameliorated metabolic inflammation. These actions enhance insulin sensitivity and improve hyperlipidemia. In vitro, treating a rat hepatoma cell line, McA-RH7777 (McA), with trigonelline is able to recapitulate the results observed in vivo., Conclusions: This study unveils a novel mechanism of fenugreek seed and trigonelline in countering hepatic VLDL overproduction and insulin resistance by enhancing the Insig signaling pathways and ameliorating metabolic inflammatory stress in the liver., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

NOD-like receptor family caspase recruitment domain family domain containing 5 (NLRC5) has important roles in inflammation and innate immunity. NLRC5 was highly expressed in kidney from streptozotocin-induced diabetic mice, db/ db mice and patients with diabetes. Based on that evidence, the present study was designed to explore the roles of NLRC5 in the progression of diabetic nephropathy (DN). We examined kidney injury, including inflammation and fibrosis in Nlrc5 gene knockout ( Nlrc5 -/- ) and wild-type (WT) diabetic mice. We found that Nlrc5 -/- mice developed less-severe diabetic kidney injury compared with WT mice, exhibiting lower albuminuria, less fibronectin and collagen IV expression, and reduced macrophage infiltration but greater levels of podocin and nephrin in the diabetic kidney. The underlying mechanisms were further investigated in vitro with peritoneal macrophages and mesangial cells treated with high glucose. Reduced proinflammatory effect was observed in peritoneal macrophages from Nlrc5 -/- mice, associated with NF-κB pathway suppression. Knocking down of NLRC5 in mesangial cells in high-glucose conditions was also associated with reduced NF-κB and TGF-β/Smad signaling. Taken together, NLRC5 promotes inflammation and fibrosis during DN progression partly through the effects on NF-κB and TGF-β/Smad pathways. NLRC5 may, therefore, be a promising therapeutic target for DN treatment.-Luan, P., Zhuang, J., Zou, J., Li, H., Shuai, P., Xu, X., Zhao, Y., Kou, W., Ji, S., Peng, A., Xu, Y., Su, Q., Jian, W., Peng, W. NLRC5 deficiency ameliorates diabetic nephropathy through alleviating inflammation.

Background/aims: Coronary microembolization (CME) is a common complication of acute coronary syndrome (ACS) and percutaneous coronary intervention (PCI); Myocardial inflammation, caused by CME, is the main cause of cardiac injury. TLR4/MyD88/NF-κB signaling plays an important role in the development of myocardial inflammation, but its effects on CME remain unclear. To assess the cardiac protective effects of TAK-242 (TLR4 specific inhibitor) on CME-induced myocardial injury, and explore the underlying mechanism., Methods: Cardiac function, serum c-troponin I level, microinfarct were examined by cardiac ultrasound, myocardial enzyme assessment, HBFP staining. The levels of TLR4/MyD88/NF-κB signaling and NLRP3 inflammasome pathway were detected by ELISA, qRT-PCR and western blot., Results: The results showed inflammatory responses in the myocardium after CME, with increased expression levels of pro-inflammatory factors TNF-α, IL-1β and IL-18. Meanwhile, TLR4/MyD88/NF-κB signaling and the NLRP3 inflammasome were involved in the inflammatory process. TAK-242 administration before CME effectively inhibited the inflammatory response in the rat myocardium after CME and reduced myocardial injury, mainly by inhibiting TLR4/ MyD88/NF-κB signaling and reducing NLRP3 inflammasome activation. In addition, in vitro assays with neonatal rat cardiomyocytes further confirmed that TLR4/MyD88/NF-κB signaling was significantly activated in the inflammatory response of LPS-induced cardiomyocytes, via activation of the NLRP3 inflammasome. Inhibition of TLR4/MyD88/NF-κB signaling resulted in increased survival of cardiomyocytes mainly by reducing the release of inflammatory cytokines and decreasing NLRP3 inflammasome activation., Conclusions: TLR4/MyD88/NF-κB signaling participates in the inflammatory response of the myocardium after CME, activating the NLRP3 inflammasome, promoting the inflammatory cascade, and aggravating myocardial injury. Blocking TLR4/MyD88/NF-κB signaling may help reduce myocardial injury and improve cardiac function after CME., (© 2018 The Author(s). Published by S. Karger AG, Basel.)

CD44, a cell adhesion protein, involves in various process in cancer such as cell survival and metastasis. Most researches on CD44 in cancer focus on cancer cells. Recently, it is found that CD44 expression is high in fibroblasts of tumour microenvironment. However, its role in communication between fibroblasts and breast cancer cells is seldom known. In this study, CD44-positive (CD44 + Fbs) and CD44-negative carcinoma-associated fibroblasts (CD44 - Fbs) were isolated and cocultured with breast cancer cells for analysis of cell survival and drug resistance. We found that CD44 + Fbs promoted breast cancer cell survival and paclitaxel resistance and inhibited paclitaxel-induced apoptosis. Our further research for the molecular mechanism showed that IGF2BP3 bound to CD44 mRNA and enhanced CD44 expression, which increased IGF2 levels of fibroblasts and then stimulated breast cancer cell proliferation and drug resistance. IGF2 was found to activate Hedgehog signal pathway in breast cancer cells. In conclusion, the results illustrated that in CD44 + Fbs, binding of IGF2BP3 and CD44 promotes IGF2 expression and then accelerates breast cancer cell proliferation, survival and induced chemotherapy resistance likely by activating Hedgehog signal pathways., (© 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

Ulva pertusa lectin 1 (UPL1) is a N-acetyl-D-glucosamine (GlcNAc) binding lectin in marine green alga Ulva pertusa. Exogenous UPL1 colocalized with protein arginine methyltransferase 5 (PRMT5), methylosome protein 50 (MEP50), β-actin and β-tubulin, indicating the interaction of UPL1 with the methylosome and cytoskeleton. UPL1 delivery through adenovirus vector (Ad-UPL1) dramatically induced extracellularly regulated protein kinases 1/2 (ERK1/2) phosphorylation in liver cancer cell lines BEL-7404 and Huh7. Signaling pathways including p38 mitogen-activated protein kinase (MAPK), and Akt were also affected by Ad-UPL1 in a cell type dependent manner. MEK1/2 inhibitor U0126, as well as to a lesser extent p38 MAPK inhibitor SB203580 and phosphoinositide 3-kinase (PI3K) inhibitor LY294002, completely eliminated a higher molecular weight isoform of β-tubulin induced by Ad-UPL1, and significantly enhanced the cytotoxicity of Ad-UPL1 in Huh7 cells, suggesting that the inhibition of MEK1/2, p38 MAPK, and PI3K enhanced antiproliferative effect of Ad-UPL1 possibly through regulating the modification of β-tubulin. Ad-UPL1 completely inhibited the expression of autophagy-related factor Beclin1, but induced LC3-II expression in Huh7 cells. In addition, Ad-UPL1 significantly enhanced starvation induced survival suppression in Huh7 cells. Our data elucidated intracellular signaling pathways affected by exogenous UPL1, and may provide insights into a novel way of UPL1 delivery through adenovirus vectors combined with survival signaling inhibitors for cancer treatment.

Brain renin-angiotensin system (RAS) could regulate oxidative stress in the paraventricular nucleus (PVN) in the development of hypertension. This study was designed to explore the precise mechanisms of RAS acting on reactive oxygen species (ROS) in salt-induced hypertension. Male Wistar rats were administered with a high-salt diet (HS, 8.0% NaCl) for 8 weeks to induced hypertension. Those rats were received PVN infusion of AT1R antagonist losartan (LOS, 10 μg/h) or microinjection of small interfering RNAs for protein kinase C γ (PKCγ siRNA) once a day for 2 weeks. High salt intake resulted in higher levels of AT1R, PKCγ, Rac1 activity, superoxide and malondialdehyde (MDA) activity, but lower levels of copper/zinc superoxide dismutase (Cu/Zn-SOD), superoxide dismutase (SOD) and glutathione (GSH) in PVN than control animals. PVN infusion of LOS not only attenuated the PVN levels of AT1R, PKCγ, Rac1 activity, superoxide and decreased the arterial pressure, but also increased the PVN antioxidant capacity in hypertension. PVN microinjection of PKCγ siRNA had the same effect on LOS above responses to hypertension but no effect on PVN level of AT1R. These results, for the first time, identified that the precise signaling pathway of RAS regulating ROS in PVN is via AT1R/PKCγ/Rac1 in salt-induced hypertension.

Key Message: Histochemical staining and RNA-seq data demonstrated that the ROS- and plant hormone-regulated stress responses are the key early events of narciclasine signaling in Arabidopsis root cells. Narciclasine, an amaryllidaceae alkaloid isolated from Narcissus tazetta bulbs, employs a broad range of functions on plant development and growth. However, its molecular interactions that modulate these roles in plants are not fully understood. To elucidate the global responses of Arabidopsis roots to short-term narciclasine exposure, we first measured the accumulation of H 2 O 2 and O 2 - with histochemical staining, and then profiled the gene expression pattern in Arabidopsis root tips treated with 0.5 µM narciclasine across different exposure times by RNA-seq. Physiological measurements showed a significant increase in H 2 O 2 began at 30-60 min of narciclasine treatment and O 2 - accumulated by 120 min. Compared with controls, 236 genes were upregulated and 54 genes were downregulated with 2 h of narciclasine treatment, while 968 genes were upregulated and 835 genes were downregulated with 12 h of treatment. The Gene Ontology analysis revealed that the differentially expressed genes were highly enriched during oxidative stress, including those involved in the "regulation of transcription", "response to oxidative stress", "plant-pathogen interaction", "ribonucleotide binding", "plant cell wall organization", and "ribosome biogenesis". Moreover, Kyoto Encyclopedia of Genes and Genomes pathway enrichment statistics suggested that carbohydrate metabolism, amino acid metabolism, amino sugar and nucleotide sugar metabolism, and biosynthesis of phenylpropanoid and secondary metabolites were significantly inhibited by 12 h of narciclasine exposure. Hence, our results demonstrate that hormones and H 2 O 2 are important regulators of narciclasine signaling and help to uncover the factors involved in the molecular interplay between narciclasine and phytohormones in Arabidopsis root cells.

Major depression is a common long-lasting or recurrent psychiatric disease with high lifetime prevalence and high incidence of suicide. The main purpose of the current study was to verify whether liquiritigenin conferred an antidepressant-like effect on the depressive mouse model established by unpredictable chronic mild stress (UCMS) and explore its possible mechanism. The results of depression-related behaviors including sucrose preference test (SPT), open field test (OFT), forced swimming test (FST) and tail suspension test (TST) indicated that both liquiritigenin (7.5mg/kg, 15mg/kg) and fluoxetine (20mg/kg) dramatically improved the depression symptoms. Enzyme-linked immunosorbent assay (ELISA) revealed that treatment with liquiritigenin significantly reduced the concentrations of pro-inflammatory cytokines including interleukin (IL)-6, IL-1β and tumor necrosis factor (TNF)-α in serum and hippocampus. Compared with the UCMS group, the administrations of liquiritigenin, increased levels of superoxide dismutase (SOD), glutathione (GSH), catalase (CAT), and decreased Malondialdehyde (MDA) content. Meanwhile, glucocorticoids (GC) content was reduced in the liquiritigenin group, which suggested that liquiritigenin exhibiting the ameliorative effect on activated hypothalamic-pituitary-adrenal (HPA) axis stimulated with UCMS. Mice treated with liquiritigenin showed restored levels of neurotransmitter norepinephrine (NE) and serotonin (5-HT). Western blot analysis displayed up-regulated expressions of p-phosphatidylinositol 3-kinase (PI3K), p-Akt, p- mammalian target of rapamycin (mTOR), p-tropomyosin-related kinase B (TrkB), brain-derived neurotrophic factor (BDNF). Thus, it was supposed that liquiritigenin might be useful for the treatment of chronic depression possibly through PI3K/Akt/mTOR mediated BDNF/TrkB pathway., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: Akkermansia muciniphila (A muciniphila) is a mucin-degrading bacterium that resides in the mucus layer whose abundance inversely correlates with body weight and the development of diabetes mellitus in mice and humans. The objective of this study was to explore the regulatory effect of A muciniphila on host lipoprotein metabolism, insulin sensitivity, and hepatic metabolic inflammation., Approach and Results: By establishing a novel mouse model that colonized the A muciniphila in the gastrointestinal tract of the cAMP-responsive binding protein H (CREBH)-deficient mouse and in vivo chylomicron assay, we found that increased colonization of A muciniphila in the gastrointestinal tract of wild-type mice protected mice from an acute fat load-induced hyperlipidemia compared with vehicle-treated mice. A muciniphila administration also significantly ameliorated chronic hypertriglyceridemia, improved insulin sensitivity, and prevented overproduction of postprandial chylomicrons in CREBH-null mice. Mechanistic studies revealed that increased A muciniphila colonization induced expression of low-density lipoprotein receptors and apolipoprotein E in the hepatocytes of CREBH-null mice, which facilitated the uptake of intermediate-density lipoprotein via the mediation of apolipoprotein B100 and apolipoprotein E, leading to the increased clearance of triglyceride-rich lipoprotein remnants, chylomicron remnants, and intermediate-density lipoproteins, from the circulation. Treatment with A muciniphila further improved hepatic endoplasmic reticulum stress and metabolic inflammation in CREBH-null mice., Conclusions: Increased colonization of the disease-protective gut bacteria A muciniphila protected the host from acute and chronic hyperlipidemia by enhancing the low-density lipoprotein receptor expression and alleviating hepatic endoplasmic reticulum stress and the inflammatory response in CREBH-null mice., (© 2016 American Heart Association, Inc.)

Notch is an evolutionarily conserved signaling pathway that plays a critical role in specifying cell fate and regulating tissue homeostasis and carcinogenesis. Studies using organ cultures and genetically engineered mouse models have demonstrated that Notch signaling regulates prostate development and homeostasis. However, the role of the Notch signaling pathway in prostate cancer remains inconclusive. Many published studies have documented consistent deregulation of major Notch signaling components in human prostate cancer cell lines, mouse models for prostate cancers, and human prostate cancer specimens at both the mRNA and the protein levels. However, functional studies in human cancer cells by modulation of Notch pathway elements suggest both tumor suppressive and oncogenic roles of Notch. These controversies may originate from our inadequate understanding of the regulation of Notch signaling under versatile genetic contexts, and reflect the multifaceted and pleiotropic roles of Notch in regulating different aspects of prostate cancer cell biology, such as proliferation, metastasis, and chemo-resistance. Future comprehensive studies using various mouse models for prostate cancer may help clarify the role of Notch signaling in prostate cancer and provide a solid basis for determining whether and how Notch should be employed as a therapeutic target for prostate cancer.

Objective: In this study, we explore the effects of pretreatment with atorvastatin on the cardiac function of piglets after coronary microembolization (CME)., Methods: Twenty Bama miniature pigs were randomized to sham surgery group (sham group), CME Group, conventional dose group and intensive-dose group, with 5 miniature pigs in each group. Pigs in the CME group received a total dosage of 100,000 microspheres (42 μm) suspended in 10 ml normal saline within 40 min, while animals in the sham group received the same dosage of normal saline. In the conventional dose group, atorvastatin (1.5mg/kg) was given once daily starting 7d before microembolization. In the intensive-dose group, atorvastatin (1.5mg/kg) was also given once daily 7d before intervention, and an additional 3mg/kg 4h before percutaneous coronary intervention. Cardiac function indices were determined by echocardiography; and infarct size was determined histopathologically. PDCD4 mRNA and TNF-α mRNA and protein expression were evaluated by quantitative fluorescence-polymerase chain reaction and Western blot, respectively. NF-κB activation was evaluated by electrophoretic mobility shift assay., Results: (1) Cardiac function was significantly lower (P<0.05) in CME group compared with the sham group. CME reduced myocardial systolic dysfunction and left ventricular dilatation. The conventional and intensive-dose groups showed improved CME-induced cardiac function when compared with the CME Group (P<0.05). (2) Compared with the conventional group, the dose-intensive group showed lower PDCD4 and TNF-α expression and NF-κB activation as well as improved cardiac function (P<0.05)., Conclusions: Atorvastatin effectively improved CME-induced cardiac damage with intensive-dose therapy showing better outcome. The protective effects are mediated via suppression of PDCD4/NF-κB/TNF-α signaling in cardiomyocytes., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The aim of this study was to investigate the role of the programmed cell death factor 4 (PDCD4)/nuclear factor-κB (NF-κB) signaling pathway in coronary micro-embolism (CME)-induced inflammatory responses and cardiac dysfunction in a porcine model. Bama miniature pigs were randomly divided into four groups (n = 5 per group). Micro-embolization balls or saline were infused through a microcatheter in the left anterior descending (LAD) artery in the CME and Sham groups, respectively. PDCD4 siRNA or control siRNA mixed with transfection reagent was infused via the LAD artery 72 h before CME induction in the CME + siRNA-PDCD4 and siRNA-control groups, respectively. Cardiac function was evaluated with ultrasound. Tissue biopsy was stained with hematoxylin-eosin (HE) and hematoxylin basic fuchsin picric acid (HBFP) to measure infarction area. Myocardial PDCD4 and tumor necrosis factor-α (TNF-α) mRNA and protein expression were analyzed by quantitative PCR and Western blotting. NF-κB activity was evaluated in gel electrophoretic mobility shift assay. Echocardiographic parameters showed that compared with the sham group, the CME group had impaired heart function, manifested as systolic dysfunction and left ventricular dilatation (reduced left ventricular ejection fraction [LVEF], left ventricular fractional shortening [FS], and cardiac output [CO] [P < 0.05] and increased left ventricular end-diastolic diameter [LVEDd] [P < 0.05]). Compared with the CME group, the CME + siRNA-PDCD4 group had attenuated CME-induced cardiac function damage (increased LVEF, FS and CO [P < 0.05] and reduced LVEDd [P < 0.05]). Compared with the sham group, the CME group had significantly increased PDCD4 and TNF-α mRNA and protein expression and increased NF-κB activity (P < 0.05). These effects were significantly inhibited in the CME + siRNA-PDCD4 group (P < 0.05). In conclusion, PDCD4/NF-κB signaling pathway activation is an important mechanism for CME-induced cardiac dysfunction, suggesting that inhibition of PDCD4/NF-κB signaling pathway may be a potential target for the prevention and treatment of CME., (© 2015 by the Society for Experimental Biology and Medicine.)

Osteoclasts, the primary bone resorbing cells, are responsible for destructive bone diseases such as postmenopausal osteoporosis, rheumatoid arthritis, and periodontitis. Many plant-derived traditional medicines that might suppress the formation and/or function of osteoclasts are promising treatments for osteoclast-related diseases. In this study, we investigated the effects of leonurine hydrochloride (LH) on receptor activator NF-κB ligand (RANKL)-induced osteoclastogenesis and ovariectomy-induced bone loss. LH is a synthetic chemical compound based on the structure of leonurine, which is found in motherwort and has been reported to exhibit phytoestrogenic activity. In RAW 264.7 cells and mouse bone marrow monocytes (BMMs), LH suppressed RANKL-induced osteoclastogenesis and actin ring formation in a dose-dependent manner. LH targeted RANKL-induced osteoclastogenesis and bone resorption at an early stage. Molecular analysis demonstrated that LH attenuated RANKL-induced NF-κB signaling by inhibiting the phosphorylation and degradation of IκBα and NF-κB p65 nuclear translocation. LH inhibited the RANK-TRAF6 association triggered by RANKL binding and the phosphatidylinositol 3-kinase (PI3K)/Akt axis, without significantly affecting the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) and AP-1 signaling pathways. LH attenuated the RANKL-stimulated expression of osteoclast-related genes including NFATc1, tartrate resistant acid phosphatase (TRAP), cathepsin K, and osteoclast-associated receptor (OSCAR). Consistent with the in vitro results, LH administration attenuated osteoclast activity, thus preventing bone loss caused by estrogen deficiency in mice. In this study, LH suppressed RANKL-induced osteoclastogenesis via RANK-TRAF6, NF-κB, and PI3K/Akt signaling. These data provide the first evidence that LH might be a promising therapeutic compound to treat osteoclast-related diseases, such as osteoporosis., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Dominant mutations in superoxide dismutase 1 (SOD1) are a frequent cause of the lethal neurodegenerative disease amyotrophic lateral sclerosis (ALS). The nuclear factor erythroid 2‑related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway is the major cellular defense mechanism against oxidative stress, however, its role in ALS remains to be fully elucidated. Therefore, the present study aimed to investigate whether the human SOD1-G93A gene affected the Nrf2/ARE signaling pathway in an ALS cell model. The soma became round and the number of neurites decreased in the NSC-34 cells transfected with the hSOD1-G93A gene, and the neurites were shorter and oxidative stress was increased compared with the normal NSC-34 cells. Furthermore, the mRNA and protein expression of Nrf2, heme oxygenase-1 and, Nad(p)h: quinone oxidoreductase 1 was significantly decreased in the NSC-34 cells transfected with the human SOD1-G93A gene. The present study indicated that human SOD1-G93A damaged the Nrf2/ARE signaling pathway in the ALS cell model and reduced the ability of cells to protect against oxidative injury.

Emerging evidence demonstrates a close interplay between disturbances in mitochondrial function and ER homeostasis in the development of the metabolic syndrome. The present investigation sought to advance our understanding of the communication between mitochondrial dysfunction and ER stress in the onset of hepatic steatosis in male rodents with defective peroxisome proliferator-activated receptor-α (PPARα) signaling. Genetic depletion of PPARα or perturbation of PPARα signaling by high-fructose diet compromised the functional activity of metabolic enzymes involved in mitochondrial fatty acid β-oxidation and induced hepatic mitochondrial stress in rats and mice. Inhibition of PPARα activity further enhanced the expression of apolipoprotein B (apoB) mRNA and protein, which was associated with reduced mRNA expression of the sarco/endoplasmic reticulum calcium ATPase (SERCA), the induction of hepatic ER stress, and hepatic steatosis. Restoration of PPARα activity recovered the metabolic function of the mitochondria and ER, alleviated systemic hypertriglyceridemia, and improved hepatic steatosis. These findings unveil novel roles for PPARα in mediating stress signals between hepatic subcellular stress-responding machinery and in the onset of hepatic steatosis under conditions of metabolic stress., (Copyright © 2014 the American Physiological Society.)

The aim of this study was to explore the molecular mechanisms of the diallyl disulfide (DADS)-mediated downregulation of LIM kinase-1 (LIMK1) and the consequent inhibition of the migration and invasion of human colorectal cancer cells. RNA interference technology was used to establish stable LIMK1-miRNA/SW480 cell lines. The effects of DADS and LIMK1 RNA interference on the migration and invasion of SW480 cells were observed by scratch wound healing assay and Transwell migration assay. The effects of DADS on signaling molecules of the Rac1-Rho kinase (ROCK)1/p21-activated kinase (PAK)1-LIM kinase (LIMK)1-actin depolymerizing factor (ADF)/cofilin pathway in SW480 cells were examined by RT-PCR and western blot analysis. The healing and migration rate of the SW480 cells was significantly reduced and the cell penetrating ability was significantly suppressed (P<0.05) following treatment with DADS (45 mg/l). The immunohistochemistry and western blot analysis results showed that DADS significantly downregulated LIMK1 protein expression and suppressed LIMK1 protein phosphorylation. Furthermore, the RT-PCR and western blot analysis results revealed that DADS suppressed Rac1, ROCK1, PAK1, LIMK1 and destrin mRNA and protein expression, as well as the protein phosphorylation of LIMK1 and cofilin 1. The data demonstrate that LIMK1 expression positively correlates with the SW480 cell migration and invasion ability. DADS downregulates the Rac1-ROCK1/PAK1-LIMK1-ADF/cofilin signaling pathway, suppressing SW480 cell migration and invasion.

Cell-based subset screening of compounds using a Gli transcription factor reporter cell assay and shh stimulated cell differentiation assay identified a series of bisamide compounds as hedgehog pathway inhibitors with good potency. Using a ligand-based optimization strategy, heteroaryl groups were utilized as conformationally restricted amide isosteres replacing one of the amides which significantly increased their potency against SMO and the hedgehog pathway while decreasing activity against p38α kinase. We report herein the identification of advanced lead compounds such as imidazole 11c and 11f encompassing good p38α selectivity, low nanomolar potency in both cell assays, excellent physiochemical properties and in vivo pharmacokinetics., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Hypoxia-induced mitogenic factor (HIMF), also known as found in inflammatory zone 1 and resistin-like molecule α, belongs to a novel class of cysteine-rich secreted proteins. It exhibits mitogenic and chemotactic properties during pulmonary hypertension-associated vascular remodeling, as well as fibrogenic properties during pulmonary fibrosis. HIMF expression in the lung was reported to be regulated by Th2 cytokines (IL-4 and IL-13) via the transcription factor STAT6 pathway in a bleomycin-induced pulmonary fibrosis model. However, in this study, we found that in the hypoxia-induced pulmonary hypertension model, lung HIMF expression is increased in IL-4 and STAT6 knockout (KO) mice to the same degree as in wild-type (WT) mice, suggesting that induction of HIMF expression does not require Th2 regulation in this model. We also found that HIMF-induced proliferative activity, hypertrophy, collagen, and extracellular matrix deposition in the pulmonary arteries are significantly less in IL-4 KO mice than in WT mice. In addition, HIMF-induced production of angiogenic factors/chemokines, such as vascular endothelial growth factor, MCP-1, and stromal-derived factor-1, in the lung resident cells, as well as macrophage infiltration, were significantly suppressed in the lungs of IL-4 KO mice. We also show that IL-4 was significantly increased in the lungs of HIMF-treated WT mice. Our in vitro studies using pulmonary microvascular endothelial cells revealed that HIMF stimulated cell proliferation, vascular endothelial growth factor expression, and MCP-1 production in a manner that is dependent on the IL-4/IL-4Rα system. These findings suggest that IL-4 signaling may play a significant role in HIMF-induced lung inflammation and vascular remodeling.

Glucosamine impairs hepatic apolipoprotein B100 (apoB100) production by inducing endoplasmic reticulum (ER) stress and enhancing cotranslational and posttranslational apoB100 degradation (Qiu, W., R. K. Avramoglu, A. C. Rutledge, J. Tsai, and K. Adeli. Mechanisms of glucosamine-induced suppression of the hepatic assembly and secretion of apolipoprotein B-100-containing lipoproteins. J. Lipid Res. 2006. 47: 1749-1761). Here, we report that glucosamine also regulates apoB100 protein synthesis via ER-stress-induced PERK activation. Short-term (4 h) glucosamine treatment of HepG2 cells reduced both cellular (by 62%) and secreted apoB100 (by 43%) without altering apoB100 mRNA. Treatment with proteasomal inhibitors only partially prevented the suppressive effects of glucosamine, suggesting that mechanisms other than proteasomal degradation may also be involved. Glucosamine-induced ER stress was associated with a significantly reduced apoB100 synthesis with no significant change in posttranslational decay rates, suggesting that glucosamine exerted its effect early during apoB biosynthesis. The role of PERK and its substrate, alpha-subunit of eukaryotic initiation factor 2 (eIF2alpha), in the suppressive effects of glucosamine on apoB synthesis was then investigated. Coexpression of apoB15 (normally resistant to intracellular degradation) with wild-type double stranded (ds) RNA activated protein kinase (PKR)-like endoplasmic reticulum kinase (PERK) in COS-7 cells resulted in a dramatic reduction in the levels of newly synthesized apoB15. Interestingly, cotransfection with apoB15 and a kinase inactive PERK mutant (K618A) increased apoB15 expression. In addition, short-term glucosamine treatment stimulated an increase in phosphorylation of PERK and eIF2alpha. Taken together, these data suggest that in addition to the induction of ER-associated degradation and other degradative pathways, ER stress is associated with suppression of apoB synthesis via a PERK-dependent mechanism.

We investigated the effects of diallyl disulfide (DADS) on the induction of apoptosis in human leukemia cell line HL-60 and explored the roles of mitogen-activated protein kinase (ERK and p38 MAPK) pathways in the growth inhibition and apoptosis induced by DADS. MTT assay was used to determine the DADS induced cell growth inhibition in HL-60 cells. Flow cytometry and DNA fragmentation were used to examine the roles of apoptosis in DADS-mediated cell death. Western blot analysis of the expression of phospho-MAPKs (ERK and p38) was employed to elucidate the possible mechanisms of DADS induced apoptosis. We found that growth inhibition of HL-60 cells treated with DADS exhibited a dose-dependent response (P<0.05) and DADS induced significant apoptosis. DADS at the concentration of 10 mg/L persistently activated p38 and simultaneously reduced ERK activity. PD98059, an inhibitor of ERK upstream activators MAPK kinase MKK1 and MKK2, promoted cytotoxicity and apoptosis in HL-60 cells treated with DADS. In contrast, SB203580, an inhibitor of p38, decreased cytotoxicity and apoptosis induced by DADS. Therefore, DADS can effectively inhibit the proliferation and induce apoptosis of human leukemia cell line HL-60. Inhibition of ERK signaling pathways and activation of p38 signaling pathways are likely involved in DADS induced apoptosis in HL-60 cells.

The interferon (IFN)-inducible, double-stranded RNA activated protein kinase (PKR) is a dual-specificity kinase, which has an essential role in the regulation of protein synthesis by phosphorylating the translation eukaryotic initiation factor 2 (eIF2). Here, we show the tyrosine (Tyr) phosphorylation of PKR in response to type I or type II IFNs. We show that PKR physically interacts with either Jak1 or Tyk2 in unstimulated cells and that these interactions are increased in IFN-treated cells. We also show that PKR acts as a substrate of activated Jaks, and is phosphorylated at Tyr 101 and Tyr 293 both in vitro and in vivo. Moreover, we provide strong evidence that both the induction of eIF2alpha phosphorylation and inhibition of protein synthesis by IFN are impaired in cells lacking Jak1 or Tyk2, which corresponds to a lack of induction of PKR tyrosine phosphorylation. We conclude that PKR tyrosine phosphorylation provides an important link between IFN signalling and translational control through the regulation of eIF2alpha phosphorylation.