Synergistic upregulation of metalloproteinase-9 by growth factors and inflammatory cytokines: an absolute requirement for transcription factor NF-kappa B

Dietary Zn proteinate with moderate chelation strength alleviates heat stress-induced intestinal barrier function damage by promoting expression of tight junction proteins via the A20/NF-κB p65/MMP-2 pathway in the jejunum of broilers

BACKGROUND

The aim of this study was to determine whether and how Zn proteinate with moderate chelation strength (Zn-Prot M) can alleviate heat stress (HS)-induced intestinal barrier function damage of broilers. A completely randomized design was used for comparatively testing the effects of Zn proteinate on HS and non-HS broilers. Under high temperature (HT), a 1 (Control, HT-CON) + 2 (Zn source) × 2 (added Zn level) factorial arrangement of treatments was used. The 2 added Zn sources were Zn-Prot M and Zn sulfate (ZnS), and the 2 added Zn levels were 30 and 60 mg/kg. Under normal temperature (NT), a CON group (NT-CON) and pair-fed group (NT-PF) were included.

RESULTS

The results showed that HS significantly reduced mRNA and protein expression levels of claudin-1, occludin, junctional adhesion molecule-A (JAMA), zonula occludens-1 (ZO-1) and zinc finger protein A20 (A20) in the jejunum, and HS also remarkably increased serum fluorescein isothiocyanate dextran (FITC-D), endotoxin and interleukin (IL)-1β contents, serum diamine oxidase (DAO) and matrix metalloproteinase (MMP)-2 activities, nuclear factor kappa-B (NF-κB) p65 mRNA expression level, and protein expression levels of NF-κB p65 and MMP-2 in the jejunum. However, dietary supplementation with Zn, especially organic Zn as Zn-Prot M at 60 mg/kg, significantly decreased serum FITC-D, endotoxin and IL-1β contents, serum DAO and MMP-2 activities, NF-κB p65 mRNA expression level, and protein expression levels of NF-κB p65 and MMP-2 in the jejunum of HS broilers, and notably promoted mRNA and protein expression levels of claudin-1, ZO-1 and A20.

CONCLUSIONS

Our results suggest that dietary Zn, especially 60 mg Zn/kg as Zn-Prot M, can alleviate HS-induced intestinal barrier function damage by promoting the expression of TJ proteins possibly via induction of A20-mediated suppression of the NF-κB p65/MMP-2 pathway in the jejunum of HS broilers.

Secreted chemokines reveal diverse inflammatory and degenerative processes in the intervertebral disc of the STZ-HFD mouse model of Type 2 diabetes

The chronic inflammation present in type 2 diabetes causes many chronic inflammatory comorbidities, including cardiovascular, renal, and neuropathic complications. Type 2 diabetes is also associated with a number of spinal pathologies, including intervertebral disc (IVD) degeneration and chronic neck and back pain. Although confounding factors such as obesity are thought to increase the loads to the musculoskeletal system and subsequent degeneration, studies have shown that even after adjusting age, body mass index, and genetics (e.g. twins), patients with diabetes suffer from disproportionately more IVD degeneration and back pain. Yet the tissue-specific responses of the IVD during diabetes remains relatively unknown. We hypothesize that chronic diabetes fosters a proinflammatory microenvironment within the IVD that accelerates degeneration and increases susceptibility to painful disorders. To test this hypothesis, we evaluated two commonly used mouse models of diabetes - the leptin-receptor deficient mouse (db/db) and the chronic high-fat diet in mice with impaired beta-cell function (STZ-HFD). The db/db is a genetic model that spontaneous develop diabetes through hyperphagia, while the STZ-HFD mouse first exhibits rapid obesity development under HFD and pronounced insulin resistance following streptozotocin administration. Both animal models were allowed to develop sustained diabetes for at least twelve weeks, as defined by elevated hemoglobin A1C, hyperglycemia, and glucose intolerance. Following the twelve-week period, the IVDs were extracted in quantified in several measures including tissue-specific secreted cytokines, viscoelastic mechanical behavior, structural composition, and histopathologic degeneration. Although there were no differences in mechanical function or the overall structure of the IVD, the STZ-HFD IVDs were more degenerated. More notably, the STZ-HFD model shows a significantly higher fold increase for eight cytokines: CXCL2, CCL2, CCL3, CCL4, CCL12 (monocyte/macrophage associated), IL-2, CXCL9 (T-cell associated), and CCL5 (pleiotropic). Correlative network analyses revealed that the expression of cytokines differentially regulated between the db/db and the STZ-HFD models. Moreover, the STZ-HFD contained a fragmented and modular cytokine network, indicating greater complexities in the regulatory network. Taken together, the STZ-HFD model of type 2 diabetes may better recapitulate the complexities of the chronic inflammatory processes in the IVD during diabetes.

Hydrogen Sulfide Ameliorates Heart Aging by Downregulating Matrix Metalloproteinase-9

PURPOSE

Aging contributes significantly to cardiovascular diseases and cardiac dysfunction, leading to the upregulation of matrix metalloproteinase-9 (MMP-9) in the heart and a significant decrease in hydrogen sulfide (H2S) content, coupled with impaired cardiac diastolic function. This study explores whether supplementing exogenous hydrogen sulfide during aging ameliorates the decline in H2S concentration in the heart, suppresses MMP-9 expression, and improves the age-associated impairment in cardiac morphology and function.

METHODS

We collected plasma from healthy individuals of different ages to determine the relationship between aging and H2S and MMP-9 levels through Elisa detection and liquid chromatography-tandem mass spectrometry (LC/MC) detection of plasma H2S content. Three-month-old mice were selected as the young group, while 18-month-old mice were selected as the old group, and sodium hydrosulfide (NaHS) was injected intraperitoneally from 15 months old until 18 months old as the old + NaHS group. Plasma MMP-9 content was detected using Elisa, plasma H2S content, cardiac H2S content, and cystathionine gamma-lyase (CSE) activity were detected using LC/MC, and cardiac function was detected using echocardiography. Heart structure was assessed using hematoxylin and eosin staining, Masone staining was used to detect the degree of cardiac fibrosis, while western blot was used to detect the expression of MMP-9, CSE, and aging marker proteins. Knockdown of MMP-9 and CSE in H9c2 cells using small interfering RNA was carried out to determine the upstream-downstream relationship between MMP-9 and CSE.

RESULTS

H2S content in the plasma of healthy individuals decreases with escalating age, whereas MMP-9 level rises with age progression. Aging leads to a decrease in H2S levels in the heart and plasma of mice, severe impairment of cardiac diastolic function, interstitial relaxation, and fibrosis of the heart. Supplementing with exogenous H2S can improve these phenomena.

CONCLUSION

H2S maintains the structure and function of the heart by inhibiting the expression of MMP-9 during the aging process.

TAK-242 (Resatorvid) inhibits proinflammatory cytokine production through the inhibition of NF-κB signaling pathway in fibroblast-like synoviocytes in osteoarthritis patients

BACKGROUND

Fibroblast-like synoviocytes (FLSs) are involved in osteoarthritis (OA) pathogenesis through pro-inflammatory cytokine production. TAK-242, a TLR4 blocker, has been found to have a significant impact on the gene expression profile of pro-inflammatory cytokines such as IL1-β, IL-6, TNF-α, and TLR4, as well as the phosphorylation of Ikβα, a regulator of the NF-κB signaling pathway, in OA-FLSs. This study aims to investigate this effect because TLR4 plays a crucial role in inflammatory responses.

MATERIALS AND METHODS

Ten OA patients' synovial tissues were acquired, and isolated FLSs were cultured in DMEM in order to assess the effectiveness of TAK-242. The treated FLSs with TAK-242 and Lipopolysaccharides (LPS) were analyzed for the mRNA expression level of IL1-β, IL-6, TNF-α, and TLR4 levels by Real-Time PCR. Besides, we used western blot to assess the protein levels of Ikβα and pIkβα.

RESULTS

The results represented that TAK-242 effectively suppressed the gene expression of inflammatory cytokines IL1-β, IL-6, TNF-α, and TLR4 which were overexpressed upon LPS treatment. Additionally, TAK-242 inhibited the phosphorylation of Ikβα which was increased by LPS treatment.

CONCLUSION

According to our results, TAK-242 shows promising inhibitory effects on TLR4-mediated inflammatory responses in OA-FLSs by targeting the NF-κB pathway. TLR4 inhibitors, such as TAK-242, may be useful therapeutic agents to reduce inflammation and its associated complications in OA patients, since traditional and biological treatments may not be adequate for all of them.

Review: The PI3K-AKT-mTOR signal transduction pathway in canine cancer

Tumors in dogs and humans share many similar molecular and genetic features, incentivizing a better understanding of canine neoplasms not only for the purpose of treating companion animals, but also to facilitate research of spontaneously developing tumors with similar biologic behavior and treatment approaches in an immunologically competent animal model. Multiple tumor types of both species have similar dysregulation of signal transduction through phosphatidylinositol 3-kinase (PI3K), protein kinase B (PKB; AKT), and mechanistic target of rapamycin (mTOR), collectively known as the PI3K-AKT-mTOR pathway. This review aims to delineate the pertinent aspects of the PI3K-AKT-mTOR signaling pathway in health and in tumor development. It will then present a synopsis of current understanding of PI3K-AKT-mTOR signaling in important canine cancers and advancements in targeted inhibitors of this pathway.

Age and oxidative stress regulate Nrf2 homeostasis in human articular chondrocytes

OBJECTIVE

The purpose of this study was to investigate the effect of age and oxidative stress on regulation of nuclear factor erythroid-2-related factor 2 (Nrf2) in young, old, and osteoarthritic (OA) human articular chondrocytes.

DESIGN

Levels of Nrf2 in primary human chondrocytes isolated from young, old, and OA donors were measured by immunoblotting, qPCR, and immunohistochemistry. Effects on levels of Nrf2, antioxidant proteins regulated by Nrf2, as well as p65, and the anabolic response to insulin-like growth factor-1 (IGF-1) were evaluated after induction of oxidative stress with menadione, Nrf2 knockdown with siRNA, and/or Nrf2 activation with RTA-408.

RESULTS

Nrf2 protein levels were significantly lower in older adult chondrocytes (∼0.59 fold; p = 0.034) and OA chondrocytes (∼0.50 fold; p = 0.016) compared to younger cells. Menadione significantly increased Nrf2 protein levels in young chondrocytes by just under four-fold without changes in old chondrocytes. Nrf2 knockdown and activation differentially regulated levels of anti-oxidant proteins including sulfiredoxin and NAD(P)H quinone dehydrogenase 1. Nrf2 activation with RTA-408 also decreased basal p65 phosphorylation, increased aggrecan and type II collagen gene expression, and increased production of proteoglycans in OA chondrocytes treated with IGF-1.

CONCLUSIONS

Targeted therapeutic strategies aimed at maintaining Nrf2 activity could be useful in maintaining chondrocyte homeostasis through maintenance of intracellular antioxidant function and redox balance.

TNFα induces matrix metalloproteinase-9 expression in monocytic cells through ACSL1/JNK/ERK/NF-kB signaling pathways

Studies have established the association between increased plasma levels of matrix metalloproteinase (MMP)-9 and adipose tissue inflammation. Tumor necrosis factor α (TNFα) was elevated in obesity and is involved in the induction of MMP-9 in monocytic cells. However, the underlying molecular mechanism was incompletely understood. As per our recent report, TNFα mediates inflammatory responses through long-chain acyl-CoA synthetase 1 (ACSL1). Therefore, we further investigated the role of ACSL1 in TNFα-mediated MMP-9 secretion in monocytic cells. THP-1 cells and primary monocytes were used to study MMP-9 expression. mRNA and protein levels of MMP-9 were determined by qRT-PCR and ELISA, respectively. Signaling pathways were studied using Western blotting, inhibitors, and NF-kB/AP1 reporter cells. We found that THP-1 cells and primary human monocytes displayed increased MMP-9 mRNA expression and protein secretion after incubation with TNFα. ACSL1 inhibition using triacsin C significantly reduced the expression of MMP-9 in the THP-1 cells. However, the inhibition of β-oxidation and ceramide biosynthesis did not affect the TNFα-induced MMP-9 production. Using small interfering RNA-mediated ACSL1 knockdown, we further confirmed that TNFα-induced MMP-9 expression/secretion was significantly reduced in ACSL1-deficient cells. TNFα-mediated MMP-9 expression was also significantly reduced by the inhibition of ERK1/ERK2, JNK, and NF-kB. We further observed that TNFα induced phosphorylation of SAPK/JNK (p54/46), ERK1/2 (p44/42 MAPK), and NF-kB p65. ACSL1 inhibition reduced the TNFα-mediated phosphorylation of SAPK/JNK, c-Jun, ERK1/2, and NF-kB. In addition, increased NF-κB/AP-1 activity was inhibited in triacsin C treated cells. Altogether, our findings suggest that ACSL1/JNK/ERK/NF-kB axis plays an important role in the regulation of MMP-9 induced by TNFα in monocytic THP-1 cells.

The role of autophagy in cardiovascular disease: Cross-interference of signaling pathways and underlying therapeutic targets

Autophagy is a conserved lysosomal pathway for the degradation of cytoplasmic proteins and organelles, which realizes the metabolic needs of cells and the renewal of organelles. Autophagy-related genes (ATGs) are the main molecular mechanisms controlling autophagy, and their functions can coordinate the whole autophagic process. Autophagy can also play a role in cardiovascular disease through several key signaling pathways, including PI3K/Akt/mTOR, IGF/EGF, AMPK/mTOR, MAPKs, p53, Nrf2/p62, Wnt/β-catenin and NF-κB pathways. In this paper, we reviewed the signaling pathway of cross-interference between autophagy and cardiovascular diseases, and analyzed the development status of novel cardiovascular disease treatment by targeting the core molecular mechanism of autophagy as well as the critical signaling pathway. Induction or inhibition of autophagy through molecular mechanisms and signaling pathways can provide therapeutic benefits for patients. Meanwhile, we hope to provide a unique insight into cardiovascular treatment strategies by understanding the molecular mechanism and signaling pathway of crosstalk between autophagy and cardiovascular diseases.

The role of leukotriene B4 in cow metritis

Introduction

Metritis is a common postpartum disease in dairy cows. As a mast cell (MC) mediator, leukotriene B4 (LTB4) is the strongest phagocyte chemokine. It is important in inflammation for the recruitment of immune cells to resist infection. This study investigated the effect of LTB4 in metritis.

Material and Methods

Twenty Holstein cows 3 to 6 years old and at 6 to 10 days postpartum were selected, ten of which with postpartum metritis were the experimental group, and the other ten of which as healthy cows were the control group. The levels of LTB4, substance P (SP) and vasoactive intestinal peptide (VIP) were measured by ELISA, the expression of LTB4 receptor 2 (BLT2), matrix metalloproteinase (MMP)-2 and MMP-9 mRNA was measured by qPCR, and collagens I and IV were detected by immunohistochemical staining.

Results

Concentrations of SP and LTB4 were significantly higher, but those of VIP were significantly lower in the experimental group than those in the control group. The expression of BLT2, MMP-2 and MMP-9 mRNA was significantly higher in the experimental group than that in the control group. The expression of collagen Ⅰ and collagen Ⅳ was significantly lower in the experimental group than that in the control group.

Conclusion

In metritis, SP promotes the activation of MC and the synthesis and release of LTB4. Leukotriene B4 chemotactic immune cells promote the high expression of collagenase, which accelerated the hydrolysis of collagen, while the inhibitory effect of VIP on MC was weakened. This may further aggravate the damage to uterine tissue.

Pten associates with important gene regulatory network to fine-tune Müller glia-mediated zebrafish retina regeneration

Unlike mammals, zebrafish possess a remarkable ability to regenerate damaged retina after an acute injury. Retina regeneration in zebrafish involves the induction of Müller glia-derived progenitor cells (MGPCs) exhibiting stem cell-like characteristics, which are capable of restoring all retinal cell-types. The induction of MGPC through Müller glia-reprograming involves several cellular, genetic and biochemical events soon after a retinal injury. Despite the knowledge on the importance of Phosphatase and tensin homolog (Pten), which is a dual-specificity phosphatase and tumor suppressor in the maintaining of cellular homeostasis, its importance during retina regeneration remains unknown. Here, we explored the importance of Pten during zebrafish retina regeneration. The Pten gets downregulated upon retinal injury and is absent from the MGPCs, which is essential to trigger Akt-mediated cellular proliferation essential for retina regeneration. We found that the downregulation of Pten in the post-injury retina accelerates MGPCs formation, while its overexpression restricts the regenerative response. We observed that Pten regulates the proliferation of MGPCs not only through Akt pathway but also by Mmp9/Notch signaling. Mmp9-activity is essential to induce the proliferation of MGPCs in the absence of Pten. Lastly, we show that expression of Pten is fine-tuned through Mycb/histone deacetylase1 and Tgf-β signaling. The present study emphasizes on the stringent regulation of Pten and its crucial involvement during the zebrafish retina regeneration.

Tumour necrosis factor alpha, interleukin 1 beta and interferon gamma have detrimental effects on equine tenocytes that cannot be rescued by IL-1RA or mesenchymal stromal cell-derived factors

Tendon injuries occur commonly in both human and equine athletes, and poor tendon regeneration leads to functionally deficient scar tissue and an increased frequency of re-injury. Despite evidence suggesting inadequate resolution of inflammation leads to fibrotic healing, our understanding of the inflammatory pathways implicated in tendinopathy remains poorly understood, meaning successful targeted treatments are lacking. Here, we demonstrate IL-1β, TNFα and IFN-γ work synergistically to induce greater detrimental consequences for equine tenocytes than when used individually. This includes altering tendon associated and matrix metalloproteinase gene expression and impairing the cells' ability to contract a 3-D collagen gel, a culture technique which more closely resembles the in vivo environment. Moreover, these adverse effects cannot be rescued by direct suppression of IL-1β using IL-1RA or factors produced by BM-MSCs. Furthermore, we provide evidence that NF-κB, but not JNK, P38 MAPK or STAT 1, is translocated to the nucleus and able to bind to DNA in tenocytes following TNFα and IL-1β stimulation, suggesting this signalling cascade may be responsible for the adverse downstream consequences of these inflammatory cytokines. We suggest a superior approach for treatment of tendinopathy may therefore be to target specific signalling pathways such as NF-κB.

Inhibition of cell invasion and migration by targeting matrix metalloproteinase-9 expression via sirtuin 6 silencing in human breast cancer cells

Sirtuin 6 (SIRT6) regulation is involved in carcinogenesis. However, its role in breast cancer (BC) metastasis remains unclear. We investigated the effects of SIRT6 on protein kinase C activator- and cytokine-mediated cancer cell invasion and migration in MCF-7 and MDA-MB-231 cells and the association between SIRT6 and matrix metalloproteinase-9 (MMP-9) expression. To assess MMP-9 and SIRT6 expression in patients, protein levels in BC tissues were analyzed. MCF-7 and MDA-MB-231 cell viability was analyzed using MTT assays. SIRT6 was silenced in both cell lines and protein secretion, expression, and mRNA levels were analyzed. Transcription factor DNA activity was investigated using luciferase assays. Matrigel invasion assays were used to assess the effects of SIRT6 in both cell lines. SIRT6 and MMP-9 expression in cancer tissues was significantly higher than in paired normal breast tissues. 12-O-tetradecanoylphorbol-13-acetate (TPA) or tumor necrosis factor-α (TNF-α) increased MMP-9 expression and cell invasion and migration, but SIRT6 knockdown abolished these effects. SIRT6 overexpression additively increased TPA- and TNF-α-induced MMP-9 expression. SIRT6 knockdown suppressed the mitogen-activated protein kinase (MAPK) signaling pathway and thus TPA- and TNF-α-induced MMP-9 expression. SIRT6 silencing suppressed TPA- and TNF-α-induced nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) expressions in both cell lines, and treatment with MAPK, NF-κB, and AP-1 inhibitors reduced MMP-9 expression. The anti-invasive effects of SIRT6 in BC cells might be mediated by suppression of MAPK phosphorylation and reduction in NF-κB and AP-1 DNA activities, leading to MMP-9 downregulation, suggesting that SIRT6 modulation has the potential to target BC metastasis.

NF-κB, A Potential Therapeutic Target in Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading cause of death globally. Atherosclerosis is the basis of major CVDs - myocardial ischemia, heart failure, and stroke. Among numerous functional molecules, the transcription factor nuclear factor κB (NF-κB) has been linked to downstream target genes involved in atherosclerosis. The activation of the NF-κB family and its downstream target genes in response to environmental and cellular stress, hypoxia, and ischemia initiate different pathological events such as innate and adaptive immunity, and cell survival, differentiation, and proliferation. Thus, NF-κB is a potential therapeutic target in the treatment of atherosclerosis and related CVDs. Several biologics and small molecules as well as peptide/proteins have been shown to regulate NF-κB dependent signaling pathways. In this review, we will focus on the function of NF-κB in CVDs and the role of NF-κB inhibitors in the treatment of CVDs.

Regulation and Function of Matrix Metalloproteinase-13 in Cancer Progression and Metastasis

Matrix metalloproteinase-13 (MMP-13) is a member of the Matrix metalloproteinases (MMPs) family of endopeptidases. MMP-13 is produced in low amounts and is well-regulated during normal physiological conditions. Its expression and secretion are, however, increased in various cancers, where it plays multiple roles in tumour progression and metastasis. As an interstitial collagenase, MMP-13 can proteolytically cleave not only collagens I, II and III, but also a range of extracellular matrix proteins (ECMs). Its action causes ECM remodelling and often leads to the release of various sequestered growth and angiogenetic factors that promote tumour cell growth, invasion and angiogenesis. This review summarizes our current understanding of the regulation of MMP-13 expression and secretion and discusses the actions of MMP-13 in cancer progression and metastasis.

HSPA6 and its role in cancers and other diseases

Heat Shock Protein Family A (Hsp70) Member 6 (HSPA6) (Online Mendelian Inheritance in Man: 140555) belongs to the HSP70 family and is a partially conserved inducible protein in mammals. The HSPA6 gene locates on the human chromosome 1q23.3 and encodes a protein containing two important structural domains: The N-terminal nucleotide-binding domain and the C-terminal substrate-binding domain. Currently, studies have found that HSPA6 not only plays a role in the tumorigenesis and tumor progresses but also causes non-tumor-related diseases. Furthermore, HSPA6 exhibits to inhibit tumorigenesis and tumor progression in some types of cancers but promotes in others. Even though HSPA6 research has increased, its exact roles and mechanisms are still unclear. This article reviews the structure, expression, function, research progress, possible mechanism, and perspective of HSPA6 in cancers and other diseases, highlighting its potential role as a targeted therapeutic and prognostic marker.

Nuclear factor kappa B signaling within the rat nucleus accumbens core sex-dependently regulates cue-induced cocaine seeking and matrix metalloproteinase-9 expression

Chronic drug self-administration and withdrawal are associated with distinct neuroimmune adaptations that may increase drug craving and relapse vulnerability in humans. The nuclear factor kappa-B (NF-κB) pathway is a critical regulator of many immune- and addiction-related genes such as the extracellular matrix enzyme matrix metalloproteinase-9 (MMP-9), which is a known modulator of learning, memory, and synaptic plasticity. While some studies suggest striatal NF-κB signaling may regulate drug-conditioned behavior, no studies to date have examined whether NF-κB signaling within the nucleus accumbens core (NAc core) alters downstream neuroimmune function and cue-motivated cocaine seeking following a period of forced abstinence, whether any effects are specific to cocaine over other reinforcers, or whether sex differences exist. Here, we examined whether viral-mediated knockdown of the p65 subunit of NF-κB within the NAc core would alter MMP-9 expression and cue-induced cocaine- and sucrose-seeking behavior following a period of forced abstinence in male and female rats. We demonstrate that NAc core p65 knockdown results in a significant decrease in cue-induced cocaine seeking in males but not females. This effect was specific to cocaine, as p65 knockdown did not significantly affect cue-induced sucrose seeking in either males or females. Moreover, we demonstrate that males express higher levels of MMP-9 within the NAc core and nucleus accumbens shell (NAcSh) compared to females, and that p65 knockdown significantly decreases MMP-9 in the NAc core of males but not females among cocaine cue-exposed animals. Altogether, these results suggest that NAc core NF-κB signaling exerts modulatory control over cue-motivated drug-seeking behavior and downstream neuroimmune function in a sex-specific manner. These findings highlight the need to consider sex as an important biological variable when examining immunomodulatory mechanisms of cocaine seeking.

Cyclic-AMP Increases Nuclear Actin Monomer Which Promotes Proteasomal Degradation of RelA/p65 Leading to Anti-Inflammatory Effects

The second messenger, cAMP has potent immunosuppressive and anti-inflammatory actions. These have been attributed, in part, to the ability of cAMP-induced signals to interfere with the function of the proinflammatory transcription factor Nuclear Factor-kappa B (NF-κB). However, the mechanisms underlying the modulation of NF-κB activity by cAMP remain unclear. Here we demonstrate an important role for cAMP-mediated increase in nuclear actin monomer levels in inhibiting NF-κB activity. Elevated cAMP or forced expression of a nuclear localised polymerisation defective actin mutant (NLS-Actin_R62D) inhibited basal and TNFα induced mRNA levels of NF-κB-dependent genes and NF-κB-dependent reporter gene activity. Elevated cAMP or NLS-Actin_R62D did not affect NF-κB nuclear translocation but did reduce total cellular and nuclear RelA/p65 levels. Preventing the cAMP-induced increase in nuclear actin monomer, either by expressing a nuclear localised active mutant of the actin polymerising protein mDIA, silencing components of the nuclear actin import complex IPO9 and CFL1 or overexpressing the nuclear export complex XPO6, rescued RelA/p65 levels and NF-κB reporter gene activity in forskolin-stimulated cells. Elevated cAMP or NLS-Actin_R62D reduced the half-life of RelA/p65, which was reversed by the proteasome inhibitor MG132. Accordingly, forskolin stimulated association of RelA/p65 with ubiquitin affinity beads, indicating increased ubiquitination of RelA/p65 or associated proteins. Taken together, our data demonstrate a novel mechanism underlying the anti-inflammatory effects of cAMP and highlight the important role played by nuclear actin in the regulation of inflammation.

MMP9: A Tough Target for Targeted Therapy for Cancer

Having the capability to proteolyze diverse structural and signaling proteins, matrix metalloproteinase 9 (MMP9), one of the best-studied secretory endopeptidases, has been identified as a crucial mediator of processes closely associated with tumorigenesis, such as the extracellular matrix reorganization, epithelial to mesenchymal transition, cell migration, new blood vessel formation, and immune response. In this review, we present the current state of knowledge on MMP9 and its role in cancer growth in the context of cell adhesion/migration, cancer-related inflammation, and tumor microenvironment formation. We also summarize recent achievements in the development of selective MMP9 inhibitors and the limitations of using them as anticancer drugs.

Acupuncture Delays Cartilage Degeneration through Upregulating SIRT1 Expression in Rats with Osteoarthritis

Silent mating type information regulation 2 homolog 1 (SIRT1) has been reported to inhibit osteoarthritic gene expression in chondrocytes. Here, efforts in this study were made to unveil the specific role of SIRT1 in the therapy of acupuncture on cartilage degeneration in osteoarthritis (OA). Specifically, OA was established by the anterior cruciate ligament transection method in the right knee joint of rats, subsequent to which acupuncture was performed on two acupoints. Injection with shSIRT1 sequence–inserted lentiviruses was conducted to investigate the role of SIRT1 in acupuncture-mediated OA. Morphological changes and cell apoptosis in rat OA cartilages were examined by safranin-O staining and terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) assay, respectively. The serum levels of tumor necrosis factor (TNF)-α and interleukin (IL)-2 in OA rats were assessed by enzyme-linked immunosorbent assay (ELISA). The expressions of SIRT1, cartilage matrix degradation-related proteins (matrix metalloproteinase (MMP)-9 and ADAMTS5), NF-κB signaling-related markers (p-p65/p65 and p-IκBα/IκBα), and cartilage matrix synthesis-related proteins (collagen II and aggrecan) in the OA cartilage were analyzed by western blot. As a result, acupuncture counteracted OA-associated upregulation of TNF-α, IL-2, cartilage matrix degradation-related proteins, and NF-κB signaling-related markers, morphological damage, apoptosis, SIRT1 downregulation, and loss of cartilage matrix synthesis-related proteins in rat articular cartilages. SIRT1 silencing reversed acupuncture-induced counteractive effects on the aforementioned OA-associated phenomena (except apoptosis, the experiment regarding which under SIRT1 silencing was not performed). Collectively, acupuncture inhibited chondrocyte apoptosis, inflammation, NF-κB signaling activation, and cartilage matrix degradation by upregulating SIRT1 expression to delay OA-associated cartilage degeneration.

Rosa hybrida Petal Extract Exhibits Antitumor Effects by Abrogating Tumor Progression and Angiogenesis in Bladder Cancer Both In Vivo and In Vitro

The edible Rosa hybrida (RH) petal is utilized in functional foods and cosmetics. Although the biological function of RH petal extract is known, mechanism of action studies involving tumor-associated angiogenesis have not yet been reported. Herein, we investigated the regulatory effect of the ethanol extract of RH petal (EERH) on tumor growth and tumor angiogenesis against bladder cancer. EERH treatment inhibited the bladder carcinoma T24 cell and 5637 cell proliferation because of G₁-phase cell cycle arrest by inducing p21WAF1 expression and reducing cyclins/CDKs level. EERH regulated signaling pathways differently in both cells. EERH-stimulated suppression of T24 and 5637 cell migration and invasion was associated with the decline in transcription factor-mediated MMP-9 expression. EERH oral administration to xenograft mice reduced tumor growth. Furthermore, no obvious toxicity was observed in acute toxicity test. Decreased CD31 levels in EERH-treated tumor tissues led to examine the angiogenic response. EERH alleviated VEGF-stimulated tube formation and proliferation by downregulating the VEGFR2/eNOS/AKT/ERK1/2 cascade in HUVECs. EERH impeded migration and invasion of VEGF-induced HUVECs, which is attributed to the repressed MMP-2 expression. Suppression of neo-microvessel sprouting, induced by VEGF, was verified by treatment with EERH using the ex vivo aortic ring assay. Finally, kaempferol was identified as the main active compound of EERH. The present study demonstrated that EERH may aid the development of antitumor agents against bladder cancer.

Mulberry leaf (Morus alba L.): A review of its potential influences in mechanisms of action on metabolic diseases

The leaves of Morus alba L. (called Sangye in Chinese, ML), which belong to the genus Morus., are highly valuable edible plants in nutrients and nutraceuticals. In Asian countries including China, Japan and Korea, ML are widely used as functional foods including beverages, noodles and herbal tea because of its biological and nutritional value. Meanwhile, ML-derived products in the form of powders, extracts and capsules are widely consumed as dietary supplements for controlling blood glucose and sugar. Clinical studies showed that ML play an important role in the treatment of metabolic diseases including the diabetes, dyslipidemia, obesity, atherosclerosis and hypertension. People broadly use ML due to their nutritiousness, deliciousness, safety, and abundant active benefits. However, the systematic pharmacological mechanisms of ML on metabolic diseases have not been fully revealed. Therefore, in order to fully utilize and scale relevant products about ML, this review summarizes the up-to-date information about the ML and its constituents effecting on metabolic disease.

UBE2S activates NF-κB signaling by binding with IκBα and promotes metastasis of lung adenocarcinoma cells

PURPOSE

Nuclear factor (NF)-κB signaling in cancer cells has been reported to be involved in tumorigenesis. Phosphorylation and degradation of inhibitor of NF-κBα (IκBα) is a canonical pathway of NF-κB signaling. Here, we aimed to identify and characterize noncanonical activation of NF-κB signaling by ubiquitin-conjugating enzyme E2S (UBE2S) in lung adenocarcinoma cells.

METHODS

TCGA and the Human Atlas Protein Database were used to analyze the survival rate of lung adenocarcinoma patients in conjunction with UBE2S expression. In addition, PC9, H460, H441 and A549 lung adenocarcinoma cells were used in this study. PC9 and H460 cells were selected for further analysis because they expressed different UBE2S protein levels. Specific IKK inhibitors, PS1145 and SC514, were used to assess IκBα phosphorylation. Western blot analysis was used to assess protein levels in PC9 and H460 cells. A scratch wound-healing assay was used to analyze the migrative abilities of PC9 and H460 cells. Overexpression and knockdown of UBE2S in H460 and PC9 cells were used to analyze their effects on downstream protein levels. Immunoprecipitation, immunofluorescent staining, glutathione S transferase (GST) pull-down and in vitro binding assays were used to analyze the interaction between UBE2S and IκBα. A luciferase assay was used to analyze activation of NF-κB signaling regulated by UBE2S. An in vivo zebrafish xenograft model was used to assess metastasis of PC9 cells regulated by UBE2S.

RESULTS

We found that UBE2S expression in lung adenocarcinoma patients was negatively related to survival rate. The protein level of UBE2S was higher in PC9 cells than in H460 cells, which was opposite to that observed for IκBα. PC9 cells showed a higher UBE2S expression and migrative ability than H460 cells. Phosphorylation of IκBα was not changed by treatment with the IKK-specific inhibitors PS1145 and SC514 in PC9 and H460 cells. Overexpression and knockdown of UBE2S in H460 and PC9 cells revealed that the protein levels of IκBα were inversely regulated. Immunoprecipitation, immunofluorescent staining, GST pull-down and in vitro binding assays revealed direct binding of UBE2S with IκBα. Nuclear P65 protein levels and luciferase assays showed that NF-κB signaling was regulated by UBE2S. The expression of epithelial-to-mesenchymal (EMT) markers and the migrative ability of lung adenocarcinoma cells were also regulated by UBE2S. A zebrafish xenograft tumor model showed a reduction in the metastasis of PC9 cells that was induced by UBE2S knockdown.

CONCLUSIONS

Higher UBE2S expression in lung adenocarcinomas may lead to increased binding with IκBα to activate NF-κB signaling and promote adenocarcinoma cell metastasis. UBE2S may serve as a potential therapeutic target for lung adenocarcinomas.

Microvascular degeneration occurs before plaque onset and progresses with age in 3xTg AD mice

Heart disease and vascular disease positively correlate with the incidence of Alzheimer's disease (AD). Although there is ostensible involvement of dysfunctional cerebrovasculature in AD pathophysiology, the characterization of the specific changes and development of vascular injury during AD remains unclear. In the present study, we established a time-course for the structural changes and degeneration of the angioarchitecture in AD. We used cerebrovascular corrosion cast and µCT imaging to evaluate the geometry, topology, and complexity of the angioarchitecture in the brain of wild type and 3xTg AD mice. We hypothesized that changes to the microvasculature occur early during the disease, and these early identifiable aberrations would be more prominent in the brain subregions implicated in the cognitive decline of AD. Whole-brain analysis of the angioarchitecture indicated early morphological abnormalities and degeneration of microvascular networks in 3xTg AD mice. Our analysis of the hippocampus and cortical subregions revealed microvascular degeneration with onset and progression that was subregion dependent.

SARS-CoV-2 and pathological matrix remodeling mediators

BACKGROUND

Recognizing only sharp elevation in a short period of time, the COVID-19 SARS-CoV-2 propagation is more and more marked in the whole world. Induced inflammation afterwards infection engenders a high infiltration of immune cells and cytokines that triggers matrix metalloproteinases (MMPs) activation. These endopeptidases are mediators of the lung extracellular matrix (ECM), a basic element for alveoli structure and gas exchange.

METHODS

When immune cells, MMPs, secreted cytokines and several other mediators are gathered a pathological matrix remodeling occurs. This phenomenon tends to tissue destruction in the first place and a pulmonary hypertrophy and fibrosis in the second place.

FINDINGS

After pathological matrix remodeling establishment, pathological diseases take place even after infection state. Since post COVID-19 pulmonary fibrosis is an emerging complication of the disease, there is an urge to better understand and characterize the implication of ECM remodeling during SARS-CoV-2 infection.

CONCLUSION

Targeting MMPs and their inhibitors could be a probable solution for occurred events since there are many cured patients that remain with severe sequels even after the end of infection.

Chondro-Protective Effects of Shikimic Acid on Osteoarthritis via Restoring Impaired Autophagy and Suppressing the MAPK/NF-κB Signaling Pathway

Osteoarthritis (OA) is a major cause of cartilage pain and limited mobility in middle-aged and elderly individuals. The degeneration of cartilage induced by inflammation and cartilage anabolic and catabolic disorder plays a key role in OA. Shikimic acid (SA), a natural ingredient extracted from Illicium verum, has been shown to exert notable anti-inflammatory effects in previous studies, suggesting its potential effects in the treatment of OA. In this study, we revealed that the pretreatment of SW1353 human chondrocytes with SA before interleukin 1β (IL-1β) stimulation effectively decreased the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (Cox)-2, matrix metalloproteinases (MMPs; MMP3 and MMP13), a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-5, type X collagen, and p62; increased the expression of type II collagen, ATG7, Beclin-1, and LC3; and increased the autophagic flux. Mechanistically, we found that SA suppressed the IL-1β-induced activation of the mitogen-activated protein kinase (MAPK) and nuclear factor-kappaB (NF-κB) pathways. Furthermore, the results of safranin O staining and toluidine blue staining of primary rat cartilage chondrocytes and a trauma-induced rat model of OA showed that SA alleviated progression of OA in vivo. Collectively, our research enhances understanding of the mechanism of protective effect of SA against the progression of OA, which involves amelioration of cartilage degeneration, thereby providing new evidence for the use of SA as a therapy to prevent the development of OA.

NF-κB-activated SPRY4-IT1 promotes cancer cell metastasis by downregulating TCEB1 mRNA via Staufen1-mediated mRNA decay

Previous study demonstrated that most long non-coding RNAs (lncRNAs) function as competing endogenous RNAs or molecular sponges to negatively modulate miRNA and regulate tumor development. However, the molecular mechanisms of lncRNAs in cancer are not fully understood. Our study describes the role of the lncRNA SPRY4 intronic transcript 1 (SPRY4-IT1) in cancer metastasis by mechanisms related to Staufen1 (STAU1)-mediated mRNA decay (SMD). Briefly, we found that, high SPRY4-IT1 expression was associated with aggressiveness and poor outcome in human colorectal, breast and ovarian cancer tissues. In addition, functional assays revealed that SPRY4-IT1 significantly promoted colorectal, breast and ovarian cancer metastasis in vitro and in vivo. Mechanistically, microarray analyses identified several differentially-expressed genes upon SPRY4-IT1 overexpression in HCT 116 colorectal cancer cells. Among them, the 3'-UTR of transcription elongation factor B subunit 1 (TCEB1) mRNA can base-pair with the Alu element in the 3'-UTR of SPRY4-IT1. Moreover, SPRY4-IT1 was found to bind STAU1, promote STAU1 recruitment to the 3'-UTR of TCEB1 mRNA, and affect TCEB1 mRNA stability and expression, resulting in hypoxia-inducible factor 1α (HIF-1α) upregulation, and thereby affecting cancer cell metastasis. In addition, STAU1 depletion abrogated TCEB1 SMD and alleviated the pro-metastatic effect of SPRY4-IT1 overexpression. Significantly, we revealed that SPRY4-IT1 is also transactivated by NF-κB/p65, which activates SPRY4-IT1 to inhibit TCEB1 expression, and subsequently upregulate HIF-1α. In conclusion, our results highlight a novel mechanism of cytoplasmic lncRNA SPRY4-IT1 in which SPRY4-IT1 affecting TCEB1 mRNA stability via STAU1-mediated degradation during cancer metastasis.

Co-expression of low-risk HPV E6/E7 and EBV LMP-1 leads to precancerous lesions by DNA damage

Background

Low-risk human papillomavirus (HPV), such as types 6 and 11, is considered non-oncogenic, but these types have been detected in oral cancer tissue samples, suggesting their possible involvement in oral carcinogenesis. Because double infection of high-risk HPV and Epstein-Barr virus (EBV) is known to be involved in oral carcinogenesis, we hypothesized that low-risk HPV and EBV co-infection can transform the oral cells. To verify our hypothesis, we evaluated the transformation activity of cell lines expressing both low-risk HPV E6/E7 and EBV LMP-1.

Methods

We transduced HPV6, 11 and 16 E6/E7 genes and EBV LMP-1 gene into primary mouse embryonic fibroblasts. The cell lines were examined for indices of transformation activity such as proliferation, induction of DNA damage, resistance to apoptosis, anchorage-independent growth, and tumor formation in nude mice. To evaluate the signaling pathways involved in transformation, NF-κB and p53 activities were analyzed. We also assessed adhesion signaling molecules associated with anchorage-independent growth such as MMP-2, paxillin and Cat-1.

Results

Co-expression of low-risk HPV6 E6 and EBV LMP-1 showed increased cell proliferation, elevated NF-κB activity and reduced p53 induction. Moreover, co-expression of low-risk HPV6 E6 and EBV LMP-1 induced DNA damage, escaped from apoptosis under genotoxic condition and suppression of DNA damage response (DDR). Co-expression of low-risk HPV11 E6/E7 and EBV LMP-1 demonstrated similar results. However, it led to no malignant characteristics such as anchorage-independent growth, invasiveness and tumor formation in nude mice. Compared with the cells co-expressing high-risk HPV16 E6 and EBV LMP-1 that induce transformation, co-expression of low-risk HPV6 E6 and EBV LMP-1 was associated with low MMP-2, paxillin and Cat-1 expression.

Conclusions

The co-expression of low-risk HPV E6/E7 and EBV LMP-1 does not induce malignant transformation, but it allows accumulation of somatic mutations secondary to increased DNA damage and suppression of DDR. Thus, double infection of low-risk HPV and EBV could lead to precancerous lesions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08397-0.

Peroxisome-Proliferator Activator Receptor γ in Mouse Model with Meningoencephalitis Caused by Angiostrongylus cantonensis

Peroxisome-proliferator activator receptor γ (PPARγ) has an anti-inflammatory role that inhibits the nuclear factor-κB (NF-κB) pathway and regulates the expressions of pro-inflammatory proteins, whereas its role in parasitic meningoencephalitis remains unknown. In this study we investigated the role of PPARγ and related mechanisms in eosinophilic meningoencephalitis caused by the rat lungworm Angiostrongylus cantonensis. We observed increased protein NF-κB expression in mouse brain tissue using GW9662, which is the specific antagonist of PPARγ, in a mouse model of angiostrongyliasis. Then we investigated NF-κB-related downstream proteins, such as COX-2, NOSs, and IL-1β, with Western blot or enzyme-linked immunosorbent assay and found that the protein expression was upregulated. The results of gelatin zymography also showed that the MMP-9 activities were upregulated. Treatment with GW9662 increased the permeability of the blood-brain barrier and the number of eosinophils in cerebrospinal fluid. These results suggested that in angiostrongyliasis, PPARγ may play an anti-inflammation role in many inflammatory mediators, including NOS-related oxidative stress, cytokines, and matrix metalloproteinase cascade by decreasing the NF-κB action.

Comparative Analysis of Tear Proteins in Keratoconic Scleral Lens Wearers with Variation in Limbal Clearance

SIGNIFICANCE

Cytokine and protease analysis revealed relative changes in the post-lens tear film of scleral lenses with low and high limbal clearances. Results from this study indicate that midperipheral lens fit is an important fitting feature that can impact the inflammatory response of a keratoconic eye.

PURPOSE

The purpose of this study was to investigate changes in levels of inflammatory mediators in the post-lens tear film of keratoconic scleral lens wearers with varying limbal clearance designs.

METHODS

Twenty-two keratoconic eyes were fitted with two sets of scleral lenses that were consistent in lens diameter and central sagittal depth but varied in limbal clearance by approximately 50 μm. Lenses were worn in a randomly assigned order for a 2-week period each. At each follow-up visit, immediately after lens removal, tear samples were collected with a microcapillary tube (10 μL, 0.5 mm in diameter) from the bowl of the inverted scleral lens. Tear cytokine and protease analysis was performed using a multiplex electrochemiluminescent array (Meso Scale Discovery, Rockville, MD) instrument. Levels of interleukins 1, 6, and 8; tumor necrosis factor α; and matrix metalloproteinases 1 and 9 were compared and analyzed.

RESULTS

Levels of interleukin 1β, tumor necrosis factor α, and matrix metalloproteinase 1 increased with high limbal clearance (P = .01, .006, and .02, respectively). No change in interleukins 6 and 8 levels was found (P > .05). A decrease in matrix metalloproteinase 9 was noted in post-lens tear film of scleral lenses with high limbal clearance (P = .10).

DISCUSSION

Relative changes in the cytokine and protease levels were found when comparing low and high limbal clearance, indicating that the midperipheral lens fit is an important feature that can impact the inflammatory response of the keratoconic eye.

Curcumin suppresses the proliferation of oral squamous cell carcinoma through a specificity protein 1/nuclear factor-κB-dependent pathway

Oral squamous cell carcinoma (OSCC) is the most common cancer of the oral cavity. Curcumin (Cur), a naturally derived compound, is reported to have broad-spectrum anticancer activity and is considered as an effective nuclear factor-κB (NF-κB) inhibitor. The present study aimed to clarify the detailed molecular mechanism though which Cur regulates NF-κB pathway activity in OSCC. The viability of HSC3 and CAL33 cells following treatment with Cur was determined using a Cell Counting Kit-8 assay. The protein and mRNA expression of specificity protein 1 (Sp1), p65 and heat shock factor 1 (HSF1) was determined by western blotting and reverse transcription-quantitative PCR analysis, respectively. The NF-κB activity was measured by Dual-Luciferase reporter assay. Short hairpin RNA targeting Sp1 or control RNA was transfected into HSC3 cells using X-treme GENE HP DNA Transfection System. Colony formation assays were performed using crystal violet staining. The results demonstrated that Cur significantly inhibited the viability and colony formation ability of HSC3 and CAL33 cells. In addition, Cur decreased the expression of Sp1, p65 and HSF1 by suppressing their transcription levels. Cur decreased NF-κB activity in OSCC cells, and Sp1 downregulation enhanced the effect of Cur. The findings from the present study suggested that Cur may inhibit the proliferation of OSCC cells via a Sp1/NF-κB-dependent mechanism.

Transcriptional and signalling regulation of skin epithelial stem cells in homeostasis, wounds and cancer

The epidermis and skin appendages are maintained by their resident epithelial stem cells, which undergo long-term self-renewal and multilineage differentiation. Upon injury, stem cells are activated to mediate re-epithelialization and restore tissue function. During this process, they often mount lineage plasticity and expand their fates in response to damage signals. Stem cell function is tightly controlled by transcription machineries and signalling transductions, many of which derail in degenerative, inflammatory and malignant dermatologic diseases. Here, by describing both well-characterized and newly emerged pathways, we discuss the transcriptional and signalling mechanisms governing skin epithelial homeostasis, wound repair and squamous cancer. Throughout, we highlight common themes underscoring epithelial stem cell plasticity and tissue-level crosstalk in the context of skin physiology and pathology.

Combination of ACY-241 and JQ1 Synergistically Suppresses Metastasis of HNSCC via Regulation of MMP-2 and MMP-9

Overexpression of histone deacetylase 6 (HDAC6) and bromodomain-containing protein 4 (BRD4) is related to aggressiveness of head and neck squamous carcinoma (HNSCC). Based on studies that HDAC6 and BRD4 are potential therapeutic targets of HNSCC, we hypothesized that the combination treatment of BET inhibitor JQ1 and HDAC6-selective inhibitor ACY-241 could exhibit synergistic anticancer effects in human papillomavirus (HPV)-positive and HPV-negative HNSCC cells. In this study, HNSCC cell growth and viability were measured by CCK-8 assay, apoptosis was analyzed by flow cytometry, and metastasis was studied by wound healing and transwell assays. Furthermore, immunoblotting is conducted to investigate proteins that modulate apoptosis or metastasis. Here, we report that the combination of ACY-241 and JQ1 shows synergistic cell growth inhibition, viability reduction, and apoptosis induction in HNSCC cells through inactivation of AKT and NF-κB signaling. Importantly, we demonstrate that combined treatment of ACY-241 and JQ1 synergistically suppresses TNF-α-induced migration and invasion via dysregulating matrix metalloproteinase (MMP)-2, MMP-9, and MT1-MMP. Overall, the combination of ACY-241 and JQ1 significantly suppresses proliferation and metastasis in HPV-positive and HPV-negative HNSCC. Collectively, these findings suggest that the co-inhibition of BET and HDAC6 can be a new therapeutic strategy in HNSCC.

Carnosine Impedes PDGF-Stimulated Proliferation and Migration of Vascular Smooth Muscle Cells In Vitro and Sprout Outgrowth Ex Vivo

Carnosine, a naturally producing dipeptide, exhibits various beneficial effects. However, the possible role of carnosine in vascular disorders associated with pathological conditions, including proliferation and migration of vascular smooth muscle cells (VSMCs), largely remains unrevealed. Here, we investigated the regulatory role and mechanism of carnosine in platelet-derived growth factor (PDGF)-induced VSMCs. Carnosine inhibited the proliferation of PDGF-induced VSMCs without any cytotoxic effects. Carnosine treatment also induced G1-phase cell cycle arrest by causing a p21WAF1-mediated reduction in the expression of both cyclin-dependent kinases (CDKs) and cyclins in PDGF-treated VSMCs. Carnosine treatment suppressed c-Jun N-terminal kinase (JNK) phosphorylation in PDGF-stimulated signaling. Additionally, carnosine significantly prevented the migration of VSMCs exposed to PDGF. Carnosine abolished matrix metalloproteinase (MMP)-9 activity via reduced transcriptional binding activity of NF-κB, Sp-1, and AP-1 motifs in PDGF-treated VSMCs. Moreover, using aortic assay ex vivo, it was observed that carnosine addition attenuated PDGF-stimulated sprout outgrowth of VSMCs. Taken together, these results demonstrated that carnosine impeded the proliferation and migration of PDGF-stimulated VSMCs by regulating cell cycle machinery, JNK signaling, and transcription factor-mediated MMP-9 activity as well as prevented ex vivo sprout outgrowth of blood vessels. Thus, carnosine may be a potential candidate for preventing vascular proliferative disease.

Enforced C-Src Activation Causes Compartmental Dysregulation of PI3K and PTEN Molecules in Lipid Rafts of Tongue Squamous Carcinoma Cells by Attenuating Rac1-Akt-GLUT-1-Mediated Sphingolipid Synthesis

Pharmacologic intervention to affect the membrane lipid homeostasis of lipid rafts is a potent therapeutic strategy for cancer. Here we showed that gallic acid (GA) caused the complex formation of inactive Ras-related C3 botulinum toxin substrate 1 (Rac1)-phospho (p)-casein kinase 2 α (CK2α) (Tyr 255) in human tongue squamous carcinoma (TSC) cells, which disturbed the lipid raft membrane-targeting of phosphatidylinositol 3-kinase (PI3K)-Rac1-protein kinase B (Akt) signal molecules by inducing the association of p110α-free p85α with unphosphorylated phosphatase tensin homolog deleted on chromosome 10 (PTEN) in lipid rafts. The effects on induction of inactive Rac1-p-CK2α (Tyr 255) complex formation and attenuation of p-Akt (Ser 473), GTP-Rac1, glucose transporter-1 (GLUT-1) lipid raft membrane-targeting, and cell invasive activity by GA were counteracted either by CK2α short hairpin RNA or cellular-Src (c-Src) inhibitor PP1. PP1 treatment, GLUT-1 or constitutively active Rac1 ectopic-expression blocked GA-induced decreases in cellular glucose, sphingolipid and cholesterol of lipid raft membranes, p85α-p110α-GTP-Rac1 complexes, glucosylceramide synthase activity and increase in ceramide and p110α-free p85α-PTEN complex levels of lipid raft membranes, which reversed the inhibition on matrix metalloproteinase (MMP)-2/-9-mediated cell invasion induced by GA. Using transient ectopic expression of nuclear factor-kappa B (NF-κB) p65, MMP-2/-9 promoter-driven luciferase, and NF-κB-dependent luciferase reporter genes and NF-κB specific inhibitors or Rac1 specific inhibitor NSC23766, we confirmed that an attenuation of Rac1 activity by GA confers inhibition of NF-κB-mediated MMP-2/-9 expression and cell invasion. In conclusion, GA-induced c-Src activation is a key inductive event for the formation of inactive Rac1-p-CK2α (Tyr 255) complexes, which disturbed lipid raft compartment of PI3K and PTEN molecules by impairing Akt-regulated GLUT-1-mediated sphingolipid synthesis, and finally resulting in inhibition of TSC cell invasion.

When Innate Immunity Meets Angiogenesis-The Role of Toll-Like Receptors in Endothelial Cells and Pulmonary Hypertension

Toll-like receptors serve a central role in innate immunity, but they can also modulate cell function in various non-immune cell types including endothelial cells. Endothelial cells are necessary for the organized function of the vascular system, and part of their fundamental role is also the regulation of immune function and inflammation. In this review, we summarize the current knowledge of how Toll-like receptors contribute to the immune and non-immune functions of the endothelial cells.

Downregulation of miR-1225-5p is pivotal for proliferation, invasion, and migration of HCC cells through NFκB regulation

Background

As one of the most frequently seen malignancies, hepatocellular carcinoma (HCC) serves as the second largest contributor to malignancy‐specific mortality worldwide. MicroRNA‐1225‐5p (miR‐1225) exerts an essential impact on the growth and metastasis of many malignancies. However, the contribution of miR‐125 to HCC and the molecular mechanism of cancer cell viability and apoptosis are still unclear. We focused our research on exploring the function and molecular mechanism of miR‐1225 in regulating HCC cell growth, migration, and invasion.

Material

Quantitative PCR data showed that miR‐1225 expression was repressed in HCC cell lines and in the tissues of HCC patients, compared to that in normal human hepatic cells and tissues. Transfection of a miR‐1225 mimic inhibited cell viability and proliferation as indicated by CCK‐8 staining and MTT assay. Transwell invasion, wound healing assay, and Western blotting were performed to assess whether miR‐1225 repressed the metastasis and invasion of HCC cells, and decreased matrix metalloproteinase 9 (MMP9) expression. Further bioinformatic prediction and dual‐luciferase reporter assay suggested that miR‐1225 targeted the 3′‐UTR of NFκB p65.

Results

Overexpression of p65 protein counteracted the repressive impact of miR‐1225 on invasion, migration, and proliferation of HCC cells.

Conclusion

This research provided new evidences that miR‐1225 inhibits the viability, migration, and invasion of HCC cells by downregulation of p65.

In Vitro and In Vivo Antitumor Efficacy of Hizikia fusiforme Celluclast Extract against Bladder Cancer

Various physiological benefits have been linked to Hizikia fusiforme (HF), an edible brown seaweed. Here, fucose-containing sulfated polysaccharides were extracted from celluclast-processed HF (SPHF) and their antitumor efficacy against bladder cancer was evaluated in vitro and in vivo. SPHF possesses high sulfated polysaccharide and fucose contents and free radical scavenging activities compared to those of celluclast-processed HF extracts (CHF). SPHF inhibited bladder cancer EJ cell proliferation via G1-phase cell cycle arrest. This was due to the induction of p21WAF1 expression associated with the downregulation of CDKs and cyclins. Moreover, JNK phosphorylation was identified as an SPHF-mediated signaling molecule. SPHF treatment also hindered the migration and invasion of EJ cells by inhibiting MMP-9 expression, which was attributed to the repression of transcriptional binding to NF-κB, AP-1, and Sp-1 in the MMP-9 promoter region. In an animal study, SPHF treatment suppressed EJ tumor growth in xenograft mice similarly to cisplatin. Furthermore, no toxicity signs were found after weight loss assessment, biochemical tests, and organ tissue immunostaining during oral administration of 20–200 mg/kg SPHF for 20 days. Therefore, our study demonstrates the antitumor efficacy of SPHF in vitro and in vivo, thus highlighting its potential for bladder cancer treatment development.

Novel Barbiturate-Nitrate Compounds Inhibit the Upregulation of Matrix Metalloproteinase-9 Gene Expression in Intestinal Inflammation through a cGMP-Mediated Pathway

Matrix metalloproteinase-9 is upregulated in inflammatory bowel disease. Barbiturate nitrate hybrid compounds have been designed to inhibit MMP secretion and enzyme activity. In this study, we investigated the mechanism of action of barbiturate-nitrate hybrid compounds and their component parts using models of intestinal inflammation in vitro. Cytokine-stimulated Caco-2 cells were used in all in vitro experiments. The NO donors SNAP and DETA-NONOate were used to study the effect of NO on MMP-9 mRNA. Mechanistic elucidation was carried out using the soluble guanylate cyclase (sGC) inhibitor, ODQ, and the cGMP analogue, 8-Bromo-cGMP. Further experiments were carried out to elucidate the role of NF-κB. NO donors exerted an inhibitory effect on MMP-9 mRNA in cytokine-stimulated cells. While the non-nitrate barbiturates had a limited effect on MMP-9 expression, the hybrid compounds inhibited MMP-9 expression through its NO-mimetic properties. No effect could be observed on mRNA for MMP-1 or MMP-2. The sGC inhibitior, ODQ, abolished the nitrate-barbiturate inhibition of MMP-9 gene expression, an effect which was reversed by 8-Br-cGMP. This study shows that the barbiturate scaffold is suitable for hybrid design as an MMP-9 inhibitor in cytokine-stimulated Caco-2 cells. The inhibition of MMP-9 levels was largely mediated through a reduction in its mRNA by a sGC/cGMP pathway mediated mechanism.

Analysis of cardiovascular disease-related NF-κB-regulated genes and microRNAs in TNFα-treated primary mouse vascular endothelial cells

Activated nuclear factor-κB (NF-κB) plays an important role in the development of cardiovascular disease (CVD) through its regulated genes and microRNAs (miRNAs). However, the gene regulation profile remains unclear. In this study, primary mouse vascular endothelial cells (pMVECs) were employed to detect CVD-related NF-κB-regulated genes and miRNAs. Genechip assay identified 77 NF-κB-regulated genes, including 45 upregulated and 32 downregulated genes, in tumor necrosis factor α (TNFα)-treated pMVECs. Ten of these genes were also found to be regulated by NF-κB in TNFα-treated HeLa cells. Quantitative real-time PCR (qRT-PCR) assay confirmed the up-regulation of Egr1, Tnf, and Btg2 by NF-κB in the TNFα-treated pMVECs. The functional annotation revealed that many NF-κB-regulated genes identified in pMVECs were clustered into classical NF-κB-involved biological processes. Genechip assay also identified 26 NF-κB-regulated miRNAs, of which 21 were upregulated and 5 downregulated, in the TNFα-treated pMVECs. Further analysis showed that nine of the identified genes are regulated by seven of these miRNAs. Finally, among the identified NF-κB-regulated genes and miRNAs, 5 genes and 12 miRNAs were associated with CVD by miRWalk and genetic association database analysis. Taken together, these findings show an intricate gene regulation network raised by NF-κB in TNFα-treated pMVECs. The network provides new insights for understanding the molecular mechanism underlying the progression of CVD.

Slug, a Cancer-Related Transcription Factor, is Involved in Vascular Smooth Muscle Cell Transdifferentiation Induced by Platelet-Derived Growth Factor-BB During Atherosclerosis

Background Heart attacks and stroke often result from occlusive thrombi following the rupture of vulnerable atherosclerotic plaques. Vascular smooth muscle cells (VSMCs) play a pivotal role in plaque vulnerability because of their switch towards a proinflammatory/macrophage-like phenotype when in the context of atherosclerosis. The prometastatic transcription factor Slug/Snail2 is a critical regulator of cell phenotypic transition. Here, we aimed to investigate the role of Slug in the transdifferentiation process of VSMCs occurring during atherogenesis. Methods and Results In rat and human primary aortic smooth muscle cells, Slug protein expression is strongly and rapidly increased by platelet-derived growth factor-BB (PDGF-BB). PDGF-BB increases Slug protein without affecting mRNA levels indicating that this growth factor stabilizes Slug protein. Immunocytochemistry and subcellular fractionation experiments reveal that PDGF-BB triggers a rapid accumulation of Slug in VSMC nuclei. Using pharmacological tools, we show that the PDGF-BB-dependent mechanism of Slug stabilization in VSMCs involves the extracellular signal-regulated kinase 1/2 pathway. Immunohistochemistry experiments on type V and type VI atherosclerotic lesions of human carotids show smooth muscle-specific myosin heavy chain-/Slug-positive cells surrounding the prothrombotic lipid core. In VSMCs, Slug siRNAs inhibit prostaglandin E2 secretion and prevent the inhibition of cholesterol efflux gene expression mediated by PDGF-BB, known to be involved in plaque vulnerability and/or thrombogenicity. Conclusions Our results highlight, for the first time, a role of Slug in aortic smooth muscle cell transdifferentiation and enable us to consider Slug as an actor playing a role in the atherosclerotic plaque progression towards a life-threatening phenotype. This also argues for common features between acute cardiovascular events and cancer.

Baicalein inhibits the growth of oral squamous cell carcinoma cells by downregulating the expression of transcription factor Sp1

Oral squamous cell carcinoma (OSCC), the most common malignancy of the oral cavity, accounts for >90% of all diagnosed oral cancer cases. Baicalein, a naturally derived compound, has been shown to alter p65 and the nuclear factor (NF)‑κB pathway, thus exerting cytotoxic effects on various tumor cell types. However, the mechanism of action of baicalein in OSCC has not been fully elucidated. In the present study, the proliferation of OSCC cells treated with baicalein was examined using a CCK‑8 assay. The effects of baicalein on the cell cycle and apoptosis of OSCC cells were determined by flow cytometric analyses. The expression of specificity protein 1 (Sp1), p65 and p50 at the mRNA and protein levels was determined by reverse transcription‑quantitative PCR and western blot analysis, respectively. The results of the present study demonstrated that baicalein suppresses the proliferation of OSCC cell lines in vivo and in vitro. Baicalein also induced apoptosis of OSCC cells and arrested the cell cycle at the G0/G1 phase. Baicalein inhibited the expression of Sp1, p65 and p50 by downregulating the relative mRNA levels. Baicalein reduced the activity of NF‑κB in OSCC cells. Knockdown of Sp1 also resulted in reduced expression of p65 and p50. In addition, Sp1 silencing enhanced the effects of baicalein. In conclusion, the present study demonstrated that baicalein suppresses the growth of OSCC cells through an Sp1/NF‑κB‑dependent mechanism.

Functional characterization of a candidate tumor suppressor gene, Mirror Image Polydactyly 1, in nasopharyngeal carcinoma

Mirror Image Polydactyly 1 (MIPOL1) is generally associated with congenital anomalies. However, its role in cancer development is poorly understood. Previously, by utilizing the functional complementation approach, microcell-mediated chromosome transfer (MMCT), a tumor suppressor gene, MIPOL1, was identified. MIPOL1 was confirmed to be downregulated in nasopharyngeal carcinoma (NPC) cells and tumor tissues, and re-expression of MIPOL1 induced tumor suppression. The aim of the current study is to further elucidate the functional tumor suppressive role of MIPOL1. In our study, with an expanded sample size of different clinical stages of NPC tumor tissues, we further confirmed the downregulation of MIPOL1 in different cancer stages. MIPOL1 re-expression down-regulated angiogenic factors and reduced phosphorylation of metastasis-associated proteins including AKT, p65, and FAK. In addition, MIPOL1 was confirmed to interact with a tumor suppressor, RhoB, and re-expression of MIPOL1 enhanced RhoB activity. The functional role of MIPOL1 was further validated by utilizing a panel of wild-type (WT) and truncated MIPOL1 expression constructs. The MIPOL1 tumor-suppressive effect can only be observed in the WT MIPOL1-expressing cells. In vitro and nude mice in vivo functional studies further confirmed the critical role of WT MIPOL1 in inhibiting migration, invasion and metastasis in NPC. Overall, our study provides strong evidence about the tumor-suppressive role of MIPOL1 in inhibiting angiogenesis and metastasis in NPC.

Effects of CCL5 on the biological behavior of breast cancer and the mechanisms of its interaction with tumor‑associated macrophages

The recurrence and metastasis of breast cancer limit the effectiveness of clinical treatments, making them important issues for clinicians to address. Tumor-associated macrophages (TAMs) contribute to regulating the immune system. C-C motif chemokine ligand 5 (CCL5) is an inflammatory chemokine that promotes chemotaxis on cells involved in the immune/inflammatory response. Breast cancer cells that secrete CCL5 act on THP-1 cells, influencing the invasion and metastasis of tumors. However, knowledge remains limited regarding the mechanism underlying the effects of CCL5 on breast cancer cells and TAMs, as well as the mechanisms promoting the migration and invasion of breast cancer. The present study demonstrated that the positive expression of CCL5 was associated with lymph node status and tumor-node-metastasis stage. Treatment with ≥20 ng/ml CCL5 significantly promoted the migration and invasion of MCF-7 and MDA-MB-231 cells. CCL5-small interfering RNA intervention significantly decreased the migration and invasion of the two cell types. In vitro, THP-1 cells were successfully induced to become TAMs, which were then recruited via the chemotactic effects of CCL5. This process was achieved through the co-stimulation of phorbol-12-myristate-13- acetate, interleukin-4 (IL-4) and IL-13. The nuclear factor-κB (NF-κB) signaling pathway was activated to regulate EMT, as well as the migration and invasion process of MCF-7 cells, when co-cultured with TAMs. We also reported that blocking the expression of CCL5 in vivo may significantly inhibit the growth of human breast cancer xenografts. Therefore, targeting CCL5 may be considered as a novel therapeutic strategy for suppressing the invasion and metastasis of breast cancer.

NF-κB Signaling Pathways in Osteoarthritic Cartilage Destruction

Osteoarthritis (OA) is a type of joint disease associated with wear and tear, inflammation, and aging. Mechanical stress along with synovial inflammation promotes the degradation of the extracellular matrix in the cartilage, leading to the breakdown of joint cartilage. The nuclear factor-kappaB (NF-κB) transcription factor has long been recognized as a disease-contributing factor and, thus, has become a therapeutic target for OA. Because NF-κB is a versatile and multi-functional transcription factor involved in various biological processes, a comprehensive understanding of the functions or regulation of NF-κB in the OA pathology will aid in the development of targeted therapeutic strategies to protect the cartilage from OA damage and reduce the risk of potential side-effects. In this review, we discuss the roles of NF-κB in OA chondrocytes and related signaling pathways, including recent findings, to better understand pathological cartilage remodeling and provide potential therapeutic targets that can interfere with NF-κB signaling for OA treatment.

Nimbolide Represses the Proliferation, Migration, and Invasion of Bladder Carcinoma Cells via Chk2-Mediated G2/M Phase Cell Cycle Arrest, Altered Signaling Pathways, and Reduced Transcription Factors-Associated MMP-9 Expression

Nimbolide, an active chemical constituent of Azadirachta indica, reportedly has several physiological effects. Here, we assessed novel anticancer effects of nimbolide against bladder cancer EJ and 5637 cells. Nimbolide treatment inhibited the proliferation of both bladder cancer cell lines with an IC50 value of 3 μM. Treatment of cells with nimbolide induced G2/M phase cell cycle arrest via both Chk2-Cdc25C-Cdc2/cyclin B1-Wee1 pathway and Chk2-p21WAF1-Cdc2/cyclin B1-Wee1 pathway. Nimbolide increased JNK phosphorylation and decreased p38MAPK and AKT phosphorylation. Additionally, nimbolide impeded both wound healing migration and invasion abilities by suppressing matrix metalloproteinase-9 (MMP-9) activity. Finally, nimbolide repressed the binding activity of NF-κB, Sp-1, and AP-1 motifs, which are key transcription factors for MMP-9 activity regulation. Overall, our study indicates that nimbolide is a potential chemotherapeutic agent for bladder cancer.

The connection between the Th17 cell related cytokines and cancer stem cells in cancer: Novel therapeutic targets

Cancer Stem Cells (CSCs) are the subpopulation of cells present in the different types of cancers with capabilities of self-renewal, differentiation, and tumorigenicity when transplanted into an animal host. The research work on the CSC has been providing a promising approach for the improvement of cancer therapies in the future. The CSCs have a close connection with the cytokines related with the T helper 17 (Th17) cell and other factors present in the tumor microenvironment, and these play a pivotal role in tumor progression and metastasis. The properties of CSCs are well defined in various type of tumor which is mainly developed by chemically and spontaneously in murine cancer model but in human defined primarily on acute myeloid leukemia, glioma, and breast cancer. The role of Th1, Th2, Natural Killer cells are well described in the cancer biology, but the Th17 cells are the subset which is recently exploited, and lots of research are going on. In this Review, we summarize current findings of the characteristics and functions of the Th17 cell and its signature cytokines in different cancers and their interconnections with cancer stem cells and with their markers. We have also discussed the functional properties of CSCs and how the CSCs markers can be distinguished from normal stem cells markers. We have also talked about the strategies that are efficiently targeting of CSCs and Th17 cells in different cancers.

Loss of skin elasticity is associated with pulmonary emphysema, biomarkers of inflammation, and matrix metalloproteinase activity in smokers

BACKGROUND

Elastin breakdown and the resultant loss of lung elastic recoil is a hallmark of pulmonary emphysema in susceptible individuals as a consequence of tobacco smoke exposure. Systemic alterations to the synthesis and degradation of elastin may be important to our understanding of disease phenotypes in chronic obstructive pulmonary disease. We investigated the association of skin elasticity with pulmonary emphysema, obstructive lung disease, and blood biomarkers of inflammation and tissue protease activity in tobacco-exposed individuals.

METHODS

Two hundred and thirty-six Caucasian individuals were recruited into a sub-study of the University of Pittsburgh Specialized Center for Clinically Orientated Research in chronic obstructive pulmonary disease, a prospective cohort study of current and former smokers. The skin viscoelastic modulus (VE), a determinant of skin elasticity, was recorded from the volar forearm and facial wrinkling severity was determined using the Daniell scoring system.

RESULTS

In a multiple regression analysis, reduced VE was significantly associated with cross-sectional measurement of airflow obstruction (FEV1/FVC) and emphysema quantified from computed tomography (CT) images, β = 0.26, p = 0.001 and β = 0.24, p = 0.001 respectively. In emphysema-susceptible individuals, elasticity-determined skin age was increased (median 4.6 years) compared to the chronological age of subjects without emphysema. Plasma biomarkers of inflammation (TNFR1, TNFR2, CRP, PTX3, and SAA) and matrix metalloproteinase activity (MMP1, TIMP1, TIMP2, and TIMP4) were inversely associated with skin elasticity.

CONCLUSIONS

We report that an objective non-invasive determinant of skin elasticity is independently associated with measures of lung function, pulmonary emphysema, and biomarkers of inflammation and tissue proteolysis in tobacco-exposed individuals. Loss of skin elasticity is a novel observation that may link the common pathological processes that drive tissue elastolysis in the extracellular matrix of the skin and lung in emphysema-susceptible individuals.

Alleviation of Ultraviolet-B Radiation-Induced Photoaging by a TNFR Antagonistic Peptide, TNFR2-SKE

Ultraviolet (UV) radiation of the sunlight, especially UVA and UVB, is the primary environmental cause of skin damage, including topical inflammation, premature skin aging, and skin cancer. Previous reports show that activation of nuclear factor-κB (NF-κB) in human skin fibroblasts and keratinocytes after UV exposure induces the expression and release of proinflammatory cytokines, such as interleukin-1 (IL-1) and tumor necrosis factor-α (TNF-α), and subsequently leads to the production of matrix metalloproteases (MMPs) and growth factor basic fibroblast growth factor (bFGF). Here, we demonstrated that TNFR2-SKEE and TNFR2-SKE, oligopeptides from TNF receptor-associated factor 2 (TRAF2)-binding site of TNF receptor 2 (TNFR2), strongly inhibited the interaction of TNFR1 as well as TNFR2 with TRAF2. In particular, TNFR2-SKE suppressed UVB- or TNF-α-induced nuclear translocalization of activated NF-κB in mouse fibroblasts. It decreased the expression of bFGF, MMPs, and COX2, which were upregulated by TNF-α, and increased procollagen production, which was reduced by TNF-α. Furthermore, TNFR2-SKE inhibited the UVB-induced proliferation of keratinocytes and melanocytes in the mouse skin and the infiltration of immune cells into inflamed tissues. These results suggest that TNFR2-SKE may possess the clinical potency to alleviate UV-induced photoaging in human skin.