Hydroxyapatite composited PEEK with 3D porous surface enhances osteoblast differentiation through mediating NO by macrophage

The adverse immune response mediated by macrophages is one of the main factors that are prone to lead poor osseointegration of polyetheretherketone (PEEK) implants in clinic. Hence, endowing PEEK with immunomodulatory ability to avoid the adverse immune response becomes a promise strategy to promote bone repair. In this work, sulfonation and hydrothermal treatment were used to fabricate a three-dimensional porous surface on PEEK and hydroxyapatite composited PEEK. The hydroxyapatite composited PEEK with three-dimensional porous surface inhibited macrophages polarizing to M1 phenotype and down-regulated iNOS protein expression, which led to a nitric oxide concentration reduction in culture medium of mouse bone marrow mesenchymal stem cells (mBMSCs) under co-culture condition. The decrease of nitric oxide concentration could help to increase bone formation related OSX and ALP genes expressions and decrease bone resorption related MMP-9 and MMP-13 genes expressions via cAMP-PKA-RUNX2 pathway in mBMSCs. In summary, the hydroxyapatite composited PEEK with three-dimensional porous surface has the potential to promote osteogenesis of PEEK through immunomodulation, which provides a promising strategy to improve the bone repair ability of PEEK.

SOCS1 Mediates Berberine-Induced Amelioration of Microglial Activated States in N9 Microglia Exposed to β Amyloid

Attenuating β amyloid- (Aβ-) induced microglial activation is considered to be effective in treating Alzheimer’s disease (AD). Berberine (BBR) can reduce microglial activation in Aβ-treated microglial cells; the mechanism, however, is still illusive. Silencing of cytokine signaling factor 1 (SOCS1) is the primary regulator of many cytokines involved in immune reactions, whose upregulation can reverse the activation of microglial cells. Microglia could be activated into two different statuses, classic activated state (M1 state) and alternative activated state (M2 state), and M1 state is harmful, but M2 is beneficial. In the present study, N9 microglial cells were exposed to Aβ to imitate microglial activation in AD. And Western blot and immunocytochemistry were taken to observe inducible nitric oxide synthase (iNOS), Arginase-1 (Arg-1), and SOCS1 expressions, and the enzyme-linked immunosorbent assay (ELISA) was used to measure inflammatory and neurotrophic factor release. Compared with the normal cultured control cells, Aβ exposure markedly increased the level of microglial M1 state markers ( P < 0.05 ), including iNOS protein expression, tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6 releases, and BBR administration upregulated SOSC1 expression and the level of microglial M2 state markers ( P < 0.05 ), such as Arg-1 expression, brain-derived neurotrophic factor (BDNF), and glial cell-derived neurotrophic factor (GDNF) releases, downregulating the SOCS1 expression by using siRNA, however, significantly reversed the BBR-induced effects on microglial M1 and M2 state markers and SOCS1 expression ( P < 0.05 ). These findings indicated that BBR can inhibit Aβ-induced microglial activation via modulating the microglial M1/M2 activated state, and SOCS1 mediates the process.

Evaluation of the Inhibitory Effects of Pyridylpyrazole Derivatives on LPS-Induced PGE2 Productions and Nitric Oxide in Murine RAW 264.7 Macrophages

A series of thirteen triarylpyrazole analogs were investigated as inhibitors of lipopolysaccharide (LPS)-induced prostaglandin E2 (PGE2) and nitric oxide (NO) production in RAW 264.7 macrophages. The target compounds 1a–m have first been assessed for cytotoxicity against RAW 264.7 macrophages to determine their non-cytotoxic concentration(s) for anti-inflammatory testing to make sure that the inhibition of PGE2 and NO production would not be caused by cytotoxicity. It was found that compounds 1f and 1m were the most potent PGE2 inhibitors with IC50 values of 7.1 and 1.1 μM, respectively. In addition, these compounds also showed inhibitory effects of 11.6% and 37.19% on LPS-induced NO production, respectively. The western blots analysis of COX-2 and iNOS showed that the PGE2 and NO inhibitory effect of compound 1m are attributed to inhibition of COX-2 and iNOS protein expression through inactivation of p38.

Heterocornols from the Sponge-Derived Fungus Pestalotiopsis heterocornis with Anti-Inflammatory Activity

One strain-many compounds (OSMAC) manipulation of the sponge-derived fungus Pestalotiopsis heterocornis XWS03F09 resulted in the production of new secondary metabolites. The chemical study of the fermentation, cultivated on 3% artificial sea salt in the rice media, led to the isolation of twelve compounds, including eight new polyketide derivatives, heterocornols Q–X (1–8), one new ceramide (9), and three known analogues (10–12). The structures and absolute configurations of the new compounds were elucidated by spectroscopic data and calculated ECD analysis. Heterocornols Q (1) and R (2) are novel 6/5/7/5 tetracyclic polyketide derivatives featuring dihydroisobenzofuran and benzo-fused dioxabicyclo [4.2.1] nonane system, which might be derived from the acetyl-CoA by epoxidation, polyene cyclization, and rearrangement to form the core skeleton. Compound 12 showed moderate or weak antimicrobial activities against with MIC values ranging from 25 to 100 μg/mL. Heterocornols T and X (7 and 8) could inhibit the production of LPS-induced NO significantly, comparable to dexamethasone. Further Western blotting analysis showed 7 and 8 markedly suppressed the iNOS protein expression in LPS-induced RAW 264.7 cells in a dose-dependent manner. The result showed that 7 and 8 might serve as potential leads for development of anti-inflammatory activity.

iNOS Associates With Poor Survival in Melanoma: A Role for Nitric Oxide in the PI3K-AKT Pathway Stimulation and PTEN S-Nitrosylation

We previously showed that inducible nitric oxide synthase (iNOS) protein expression in melanoma tumor cells is associated with poor patient prognosis. Here, we analyzed the association between iNOS and the oncogenic PI3K-AKT pathway. TCGA data show that iNOS and phospho-Akt Ser473 expression were associated significantly only in the subset of tumors with genetically intact PTEN. Employing a stage III melanoma TMA, we showed that iNOS protein presence is significantly associated with shorter survival only in tumors with PTEN protein expression. These findings led to our hypothesis that the iNOS product, nitric oxide (NO), suppresses the function of PTEN and stimulates PI3K-Akt activation. Melanoma cells in response to NO exposure in vitro exhibited enhanced AKT kinase activity and substrate phosphorylation, as well as attenuated PTEN phosphatase activity. Biochemical analysis showed that NO exposure resulted in a post-translationally modified S-Nitrosylation (SNO) PTEN, which was also found in cells expressing iNOS. Our findings provide evidence that NO-rich cancers may exhibit AKT activation due to post-translational inactivation of PTEN. This unique activation of oncogenic pathway under nitrosative stress may contribute to the pathogenesis of iNOS in melanoma. Significance: Our study shows that iNOS expression is associated with increased PI3K-AKT signaling and worse clinical outcomes in melanoma patients with wt (intact) PTEN. Mutated PTEN is already inactivated. We also demonstrate that NO activates the PI3K-AKT pathway by suppressing PTEN suppressor function concurrent with the formation of PTEN-SNO. This discovery provides insight into the consequences of inflammatory NO produced in human melanoma and microenvironmental cells. It suggests that NO–driven modification provides a marker of PTEN inactivation, and represents a plausible mechanism of tumor suppressor inactivation in iNOS expressing subset of cancers.

Anti-Inflammatory and Analgesic Activities of 7-Chloro-4-(Piperazin-1-yl) Quinoline Derivative Mediated by Suppression of InflammatoryMediators Expression in Both RAW 264.7 and Mouse Models

Background: 4-Aminoquinoline derivatives possess various potential biological properties.The introduction of additional piperazine heterocyclic pharmacophoric moiety tends to haveprofound impact in increasing the activity. The present work was undertaken to investigate thein-vitro and in-vivo anti-inflammatory activity as well as the peripheral and central analgesicactivities of compound 1-(4-(7-chloroquinoline-4-yl)piperazin-1-yl)-2-(4-phenylpiperazin-1-yl)ethanone (5) in experimental models. Methods: The percentage inhibition of the lipopolysaccharide induced NO release of 7-chloro-4-(piperazin-1-yl)quinoline derivatives 1-9 was determined in RAW 264.7 murine macrophagemodel. Western blot analysis was performed to evaluate the effect of compound 5 on proteinexpression of inducible nitric oxide synthase (iNOS). Gene expression of inflammatory markerswas evaluated using real-time polymerase chain reaction. The peripheral and central analgesicactivities of compound 5 were evaluated in mice using writhing and hot-plate tests, respectively.Anti-inflammatory activity was assessed using carrageenan-induced paw edema assay in miceand serum NO and COX-2 levels were measured. Results: Compound 5 demonstrated the highest NO inhibitory activity that was accompaniedby inhibition of iNOS protein expression and decreased gene expression levels of inflammatorymarkers. It revealed a potential peripheral analgesic effect through inhibition of abdominalwrithing in mice treated with doses of 15 and 30 mg/kg and its effect was comparable to diclofenacsodium. Compound 5 possessed an analgesic activity starting from 15 min post administrationand reached its peak at 45 min which was significantly higher than that of tramadol hydrochloridesuggesting its potential as central analgesic agent. It also showed percentage of inhibition ofedema of 34, 50 and 64% at 1, 2, and 3 h respectively, post carrageenan challenge together with asignificant decrease in serum NO and COX-2 levels. Conclusion: The remarkable anti-inflammatory and analgesic activities of compound 5 couldbe attributed to the advantageous introduction of the heterocyclic 7-chloro-4-(piperazin1-yl)quinoline scaffold incorporated with N-phenylpiperzine functional groups linked together withthe ethanone pharmacophoric chain.

Indomethacin augments lipopolysaccharide-induced expression of inflammatory molecules in the mouse brain

Indomethacin and other non-steroidal anti-inflammatory drugs (NSAIDs) are used to relieve pain and fever including during infections. However, some studies suggest that NSAIDs protect against neuroinflammation, while some find no effects or worsening of neuroinflammation. We evaluated the effect of indomethacin alone on in combination with minocycline, a drug that inhibits neuroinflammation, on the expression of transcripts of neuroinflammatory molecules-induced by lipopolysaccharide (LPS) in the brain of mice. Inoculation of male BALB/c mice with LPS induced the expression of the microglia marker ionized calcium binding adaptor molecule protein, mRNA expression of the genes for cytokines interleukin-1beta (Il1b) and tumor necrosis factor-alpha (Tnf) and inducible nitric oxide synthase gene (Nos2), but not Il10, in the brain. Treatment with indomethacin had no significant effect on the cytokines or Nos2 mRNA expression in naïve animals. However, pretreatment with indomethacin increased LPS-induced Nos2 mRNA and inducible nitric oxide (iNOS) protein expression, but had no significant effect on LPS-induced mRNA expression of the cytokines. Minocycline reduced LPS-induced Il1b and Tnf, but not Nos2, mRNA expression. Treatment with indomethacin plus minocycline had no effect on LPS-induced Il1b, Tnf and Nos2 mRNA expression. In conclusion these results show that indomethacin significantly augments LPS-induced Nos2 mRNA and iNOS protein expression in the brain. In the presence of indomethacin, minocycline could not inhibit LPS-induced pro-inflammatory cytokine expression. Thus, indomethacin could exacerbate neuroinflammation by increasing the expression of iNOS and also block the anti-inflammatory effects of minocycline.

Differences in in vitro interactions between macrophages with pathogenic and environmental strains of Prototheca

Aim: We investigated the interactions between macrophage and different strains of Prototheca. Materials & method: J774A.1 macrophages were infected with clinical isolates of Prototheca ciferrii 18125 and P. ciferrii 50779 and environmental isolate of P. ciferrii N71. Phagocytosis activities were compared by colony-forming unit assays at 3, 6 and 9 h after infection. Cytokine levels were detected by RT-PCR and ELISA. iNOS protein expression was examined by western blotting. Results: All P. ciferrii strains were phagocytized by macrophages but induced different levels of cytokines in macrophages. Moreover, infected by P. ciferrii N71 upregulated much higher iNOS protein expression in J774A.1 than that infected by the clinical strains. Conclusion: Clinical and environmental P. ciferrii strains show differences in their interactions with macrophages, which may be attributed to their virulence.

Vagus Nerve Stimulation Ameliorates Renal Ischemia-Reperfusion Injury through Inhibiting NF-κB Activation and iNOS Protein Expression

Objective. In renal ischemia/reperfusion injury (RIRI), nuclear factor κB (NF-κB) initiates the expression of multiple genes involved in inflammatory disease. Inhibition of NF-κB-mediated inducible nitric oxide synthase (iNOS) expression can ameliorate RIRI. Vagus nerve stimulation (VNS) protects against various organs I/R injury. The present study was designed to elucidate the protective effect of VNS on RIRI and its influence on iNOS protein expression. Methods. Eighteen male Sprague-Dawley rats were randomly allocated into the sham group, the I/R group, and the VNS+I/R group, 6 rats per group. An RIRI model was induced by a right nephrectomy and blockade of the left renal pedicle vessels for 45 min. After 6 h of reperfusion, the blood samples and renal samples were collected. The VNS treatment was performed throughout the I/R process in the VNS+I/R group using specific parameters (20 Hz, 0.1 ms in duration, square waves) known to produce a small but reliable bradycardia. Blood was used for evaluation of renal function and inflammatory state. Renal injury was evaluated via TUNEL staining. Renal samples were harvested to evaluate renal oxidative stress, NF-κB p65 levels, and iNOS protein expression. Results. The VNS treatment reduces serum creatinine (Cr) and blood urea nitrogen (BUN) levels. Simultaneously, the levels of tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and interleukin 1-beta (IL-1β) were significantly increased in the I/R group, but VNS treatment markedly ameliorated this inflammatory response. Furthermore, the VNS ameliorated oxidant stress and renal injury, indicated by a decrease in 3-nitrotyrosine (3-NT) formation and MDA and MPO levels and an increase in the SOD level compared to that in the I/R group. Finally, the VNS also significantly decreases NF-κB p65, iNOS, and nitrite/nitrate levels compared to that in the I/R group. Conclusion. Our findings indicate that NF-κB activation increased iNOS expression and promoted RIRI and that VNS treatment attenuated RIRI by inhibiting iNOS expression, oxidative stress, and inflammation via NF-κB inactivation.

Oroxylin A Reduces Vasoconstriction in Rat Aortic Rings through Promoting NO Production and NOS Protein Expression via Estrogen Receptor Signal Pathway

Oroxylin A, a flavonoid, is naturally produced in many medicinal plants. Our previous study identified it as a phytoestrogen. Based on this, the present study investigated its vasoconstriction reducing effects and whether the action was mediated by the estrogen receptor (ER) signal pathway. Long-term in vitro treatment with oroxylin A reduced Ach-induced vasorelaxation and NE-mediated or KCl-mediated contractile responses in rat aortic rings. These effects were interfered by an ER inhibitor ICI 182,780. Rat cardiac microvascular endothelial cells (CMECs) and aortic vascular smooth muscle cells (VSMCs) were used to study the possible underlying mechanisms. Oroxylin A activated the ER signal pathway. In CMECs, it increased NO production and eNOS protein expression. In VSMCs, it promoted NO production and iNOS protein expression. These effects were also inhibited by ICI 182,780. Besides, oroxylin A stimulated ERα and ERβ protein expression in CMECs and VSMCs. All these findings suggest that the ER signal pathway takes part in the vasoconstriction reducing effects of oroxylin A.