Interleukin-19 (IL-19) induces heme oxygenase-1 (HO-1) expression and decreases reactive oxygen species in human vascular smooth muscle cells

Mendelian randomization reveals causal relationships between cytokines and male reproductive diseases

This study aims to explore the causal links between cytokines and four male reproductive disorders, namely abnormal spermatozoa (AS), male infertility, erectile dysfunction (ED), and hyperplasia of prostate (HP), employing a two-sample Mendelian randomization (MR) approach. Genetic associations with male reproductive diseases were derived from the IEU OpenGWAS project, with cytokine data from two GWASs focused on the human proteome and cytokines. Estimations were derived using inverse variance weighting, MR-Egger regression, weighted median, weighted model, and simple mode. Furthermore, the robustness of the findings was evaluated through Cochran's Q-test, MR-Egger regression, and leave-one-out sensitivity analysis. Fifteen unique cytokines were identified as having causal relationships with the risk of four male reproductive disorders. Specifically, for AS, interleukin-22 (IL-22), IL-12, and macrophage migration inhibitory factor were negatively correlated with AS, while tumor necrosis factor β levels were positively correlated with AS. In the context of male infertility, IL-2 receptor antagonist levels, IL-34, and granulocyte-colony stimulating factor levels were positively linked to male infertility, whereas IL-21 showed a negative relationship. Regarding ED, IL-19, IL-1β, and eotaxin levels were negatively associated with ED risk, while macrophage inflammatory protein 1β (MIP-1β) levels and interferon gamma-induced protein 10 levels were positively associated. As for HP, stromal-cell-derived factor 1α levels and MIP-1α levels revealed negative associations with HP. In conclusion, this MR analysis revealed that several cytokines were causally associated with male reproductive diseases and could be valuable in offering new insights for further mechanistic and clinical investigations of cytokines-associated male reproductive diseases.

IL-19 Is a Novel Lymphangiocrine Factor Inducing Lymphangiogenesis and Lymphatic Junctional Regulation

BACKGROUND

The lymphatic system functions by removing fluid, macromolecules, and immune cells to maintain tissue homeostasis. The structural organization of junctional protein complexes is vital to lymphatic function where initial lymphatics have permeable button junctions and collecting lymphatics have relatively impermeable zipper junctions. During inflammation, this junctional morphology appears to reverse, contributing to overall lymphatic malfunction. Little is known about the effects of immunomodulatory cytokines on lymphatic vessel formation and function during inflammation. The purpose of this study is to test the hypothesis that IL (interleukin)-19 promotes lymphangiogenesis and proper lymphatic function during inflammation.

METHODS

We used cultured human dermal lymphatic endothelial cells to determine IL-19 expression and its effects on lymphangiogenesis assays. Immunocytochemistry and electric cell-substrate impedance sensing determined effects on junctional morphology as it relates to permeability in vitro. RNA sequencing determined the effects of IL-19 on gene expression. Il19-/-Ldlr-/- double knockout mice were used to determine IL-19 effects on lymphatic function and lymphatic vessel visualization in vivo.

RESULTS

Endogenous IL-19 expression is induced by exogenous IL-19 and VEGF (vascular endothelial growth factor) C stimulation. IL-19 is lymphangiogenic, increasing human dermal lymphatic endothelial cell migration, network formation, and proliferation. IL-19 induces expression of transcription factors and permeability-associated genes. IL-19 induces rapid VE-cadherin (vascular endothelial cadherin) phosphorylation, increases permeability of human dermal lymphatic endothelial cell monolayers, and mitigates oxidized low-density lipoprotein-associated decrease in human dermal lymphatic endothelial cell permeability. In vivo, Il19-/-Ldlr-/- double knockout mice on a high-fat diet have impaired lymphatic drainage, decreased lymphatic branch points, and increased percentage of zippered junctions compared with control mice.

CONCLUSIONS

Taken together, these data show that IL-19 has potent effects on lymphatic vessel formation and function in vitro and that IL-19 regulates lymphatic drainage in vivo. IL-19 may represent an immunomodulatory cytokine with therapeutic potential for improving impaired lymphatic function consequent to inflammation.

Exploring the Mechanisms of Iron Overload-Induced Liver Injury in Rats Based on Transcriptomics and Proteomics

Iron is a trace element that is indispensable for the growth and development of animals. Excessive iron supplementation may lead to iron overload and elevated reactive oxygen species (ROS) production in animals, causing cellular damage. Nevertheless, the precise mechanism by which iron overload causes cell injury remains to be fully elucidated. In this study, 16 male SD rats aged 6 to 7 weeks were randomly assigned to either a control group (CON) or an iron overload group (IO). Rats in the iron overload group received 150 mg/kg iron dextran injections every three days for a duration of four weeks. The results indicated that iron treatment with iron dextran significantly increased the scores of steatosis (p < 0.05) and inflammation (p < 0.05) in the NAS score. The integrated transcriptomic and proteomic analysis suggests that HO-1 and Lnc286.2 are potentially significant in iron overload-induced liver injury in rats. In vitro experiments utilizing ferric ammonium citrate (FAC) were conducted to establish an iron overload model in rat liver-derived BRL-3A cells. The result found that FAC treatment can significantly increase the BRL-3A cell's Fe2+ content (p < 0.05), ROS (p < 0.01), lipid ROS (p < 0.01) levels, and the expression of the HO-1 gene and protein (p < 0.01), aligning with proteomic and transcriptomic findings. HO-1 inhibition can significantly decrease BRL-3A cell vitality (p < 0.01) and promote ROS (p < 0.05) and lipid ROS (p < 0.01), thus aggravating FAC-induced BRL-3A cell iron overload damage. Using the agonist of HO-1 agonist cobalt protoporphyrin (CoPP) to induce HO-1 overexpression can significantly alleviate the decrease in FAC-induced BRL-3A cell viability (p < 0.01), ROS (p < 0.01), and lipid ROS (p < 0.01). In addition, siLnc286.2 treatment can increase HO-1 expression, alleviate the decline of FAC-induced BRL-3A cell activity, and increase lipid ROS (p < 0.05) content. In conclusion, the findings of this study suggest that by suppressing the expression of Lnc286.2, we can enhance the expression of HO-1, which in turn alleviates lipid peroxidation in cells and increases their antioxidant capacity, thereby exerting a protective effect against liver cell injury induced by iron overload.

The different facets of heme-oxygenase 1 in innate and adaptive immunity

Heme oxygenase (HO) enzymes are responsible for the main oxidative step in heme degradation, generating equimolar amounts of free iron, biliverdin and carbon monoxide. HO-1 is induced as a crucial stress response protein, playing protective roles in physiologic and pathological conditions, due to its antioxidant, anti-apoptotic and anti-inflammatory effects. The mechanisms behind HO-1-mediated protection are being explored by different studies, affecting cell fate through multiple ways, such as reduction in intracellular levels of heme and ROS, transcriptional regulation, and through its byproducts generation. In this review we focus on the interplay between HO-1 and immune-related signaling pathways, which culminate in the activation of transcription factors important in immune responses and inflammation. We also discuss the dual interaction of HO-1 and inflammatory mediators that govern resolution and tissue damage. We highlight the dichotomy of HO-1 in innate and adaptive immune cells development and activation in different disease contexts. Finally, we address different known anti-inflammatory pharmaceuticals that are now being described to modulate HO-1, and the possible contribution of HO-1 in their anti-inflammatory effects.

Jujube peel polyphenols synergistically inhibit lipopolysaccharide-induced inflammation through multiple signaling pathways in RAW 264.7 cells

Jujube has great potential as food and traditional drugs in several countries. To study the anti-inflammatory influence of jujube peel polyphenols in lipopolysaccharide (LPS) induced RAW 264.7 cells through mitogen-activated protein kinase (MAPK), nuclear factor-kappa B (NF-κB) and nuclear erythroid 2-related factor 2 (Nrf2) signaling pathways. In this study, the phenolic composition of polyphenols in jujube peel was analyzed using LC-MS/MS, and which was confirmed that the main polyphenols were p-coumaric acid, catechin and rutin. Meanwhile, jujube peel polyphenols attenuated the generation of TNF-α, IL-1β, IL-6, NO and PGE₂ by inhibiting MAPK and NF-κB signaling pathways. Additionally, jujube peel polyphenol activate Nrf2 from the cytoplasm to the nucleus, regulate antioxidant enzymes and pro-inflammatory cytokines, and reduce oxidative stress and inflammatory responses. Results obtained from this study suggest that jujube peel polyphenols may alleviate oxidative stress and inflammation by inhibiting MAPK and NF-κB and activating Nrf2 signaling pathways. Furthermore, jujube peel polyphenols have a synergistic effect in the treatment of LPS-induced inflammatory in RAW 264.7 cells. In conclusion, this study not only reveals the mechanism by which jujube peel polyphenols inhibit LPS-induced inflammation in RAW 264.7 cells, but also provides guidance for the development of new anti-inflammatory drugs.

The role and transformative potential of IL-19 in atherosclerosis

Atherosclerotic cardiovascular disease is the leading cause of death worldwide. Traditionally, IL-19 was thought to be expressed in only immune cells, but studies revealed that IL-19 is also expressed in multiple atherosclerotic plaque cell types, but not normal arteries, in humans and mice. IL-19 reduces the development of atherosclerosis via multiple mechanisms, including balancing cholesterol metabolism; enhancing Th2 immune cell polarization; reducing the inflammatory response; and reducing the proliferation, migration and chemotaxis of vascular smooth muscle cells (VSMCs). Clinical and/or animal studies have primarily aimed to achieve regression and/or stabilization of atherosclerotic plaques, with regression in particular indicating a very good drug response. Most antiatherosclerotic drugs in current clinical use, including atorvastatin and alirocumab, target hyperlipidemia. Several other drugs have also been investigated in clinical trials as anti-inflammatory agents; the development of some of these agents has been terminated (canakinumab, darapladib, varespladib, losmapimod, atreleuton, setileuton, PF-04191834, veliflapon, and methotrexate), but others remain in development (ziltivekimab, tocilizumab, Somalix, IFM-2427, anakinra, mesenchymal stem cells (MSCs), colchicine, everolimus, allopurinol, and montelukast). Most of the tested drugs have shown a limited ability to reverse atherosclerosis in animal studies. Interestingly, recombinant IL-19 (rIL-19) was shown to reduce atherosclerosis development in a time- and dose-dependent manner. A low dose of rIL-19 (1 ng/g/day) reduced aortic arch and root plaque areas by 70.1% and 32.1%, respectively, in LDLR^-/- mice. At 10 ng/g/day, rIL-19 completely eliminated atherosclerotic plaques. There were no sex differences in the effects of rIL-19 on atherosclerotic mice. Thus, low-dose rIL-19 is an effective antiatherosclerotic agent, in addition to its efficacy in intimal hyperplasia, spinal cord injury, stroke, and multiple sclerosis. We propose that IL-19 is a promising biomarker and target for the diagnosis and treatment of atherosclerosis. This review considers the role and mechanism of action of IL-19 in atherosclerosis and discusses whether IL-19 is a potential therapeutic target for this condition.

Targeting Heme Oxygenase-1 in the Arterial Response to Injury and Disease

Heme oxygenase-1 (HO-1) catalyzes the degradation of heme into carbon monoxide (CO), iron, and biliverdin, which is rapidly metabolized to bilirubin. The activation of vascular smooth muscle cells (SMCs) plays a critical role in mediating the aberrant arterial response to injury and a number of vascular diseases. Pharmacological induction or gene transfer of HO-1 improves arterial remodeling in animal models of post-angioplasty restenosis, vascular access failure, atherosclerosis, transplant arteriosclerosis, vein grafting, and pulmonary arterial hypertension, whereas genetic loss of HO-1 exacerbates the remodeling response. The vasoprotection evoked by HO-1 is largely ascribed to the generation of CO and/or the bile pigments, biliverdin and bilirubin, which exert potent antioxidant and anti-inflammatory effects. In addition, these molecules inhibit vascular SMC proliferation, migration, apoptosis, and phenotypic switching. Several therapeutic strategies are currently being pursued that may allow for the targeting of HO-1 in arterial remodeling in various pathologies, including the use of gene delivery approaches, the development of novel inducers of the enzyme, and the administration of unique formulations of CO and bilirubin.

Role of the signal transducer and activator of transcription 3 protein in the proliferation of vascular smooth muscle cells

OBJECTIVES

Cardiovascular disease (CVD) remains the primary cause of morbidity and mortality worldwide. The abnormal proliferation of vascular smooth muscle cells (VSMCs) is a key event in the pathogenesis of CVD. The functional and phenotypic changes in vascular cells are mediated by complex signaling cascades that initiate and control genetic reprogramming. Many studies have demonstrated that signal transducer and activator of transcription 3 (STAT3) regulates a diverse array of functions relevant to atherosclerosis.

METHODS

In this review, we summarize the studies on the STAT3-mediated proliferation of VSMCs and subsequent CVDs such as hypertension, atherosclerosis, stroke, coronary artery disease, and myocardial infarction. Furthermore, we describe the general background of STAT3, its structure, function and regulation as well as the STAT3 signaling pathway. Finally, we highlight some potential issues and propose some solutions to these issues.Results and conclusions: STAT3 activation promotes the proliferation of VSMCs by regulating the transcription of genes. Studying the mechanism of VSMC proliferation induced by the STAT3 pathway is valuable for finding therapeutic targets for CVD.

Radical-scavenging and Pro-/anti-inflammatory Activity of Tetracycline and Related Phenolic Compounds With or Without Visible Light Irradiation

BACKGROUND/AIM

Microbial tetracycline (TC) pastes have been employed to treat oral bacterial infection. In the present study, we investigated the kinetic radical-scavenging and pro-/anti-inflammatory activity of TC with or without visible light irradiation (VLI).

MATERIALS AND METHODS

The radical-scavenging activity of TC and minocycline (MC) was determined by differential scanning calorimetry (DSC). The stoichiometric factor (n) and the rate constant of inhibition and propagation (kinh/kp) were determined. The levels of cyclooxygenase-2 (Cox2), tumor necrosis factor-α (Tnfα) or nitric oxide synthase 2 (Nos2) mRNA in RAW264.7 cells stimulated with lipopolysaccharide (LPS) were investigated using real-time reverse transcriptase-polymerase chain reaction.

RESULTS

The n and kinh/kp values for 1 mM TC in 2,2'-azobisisobutyronitrile and benzoyl peroxide systems were 0.1-0.2 and 119-250, respectively, whereas the corresponding values for quercetin (QU) and resveratrol (RE) were 2-4 and 7-15, respectively. In RAW264.7 cells stimulated with LPS, Cox2 and Tnfα mRNA were over-expressed in the presence of TC. MC down-regulated only the expression of Cox2 by about 50% in LPS-stimulated cells. The anti-inflammatory activity determined on the basis of Cox2 inhibition declined in the order QU>RE>MC>TC. Upon application of VLI, only TC down-regulated the expression of LPS-stimulated Cox2 and Tnfα mRNA. After exposure to VLI, TC, but not MC, markedly up-regulated hemoxygenase-1 (Ho-1) expression.

CONCLUSION

TC is a chain-breaking antioxidant with a large kinh Upon activation by VLI, TC may undergo degradation and its degradation products affect pleiotropic mediators such as Cox2, Tnfα and Ho-1. TC may be useful as a local photodynamic therapy for periodontal diseases.

Heracleum moellendorffii roots inhibit the production of pro-inflammatory mediators through the inhibition of NF-κB and MAPK signaling, and activation of ROS/Nrf2/HO-1 signaling in LPS-stimulated RAW264.7 cells

BACKGROUND

Heracleum moellendorffii roots (HM-R) have been long treated for inflammatory diseases such as arthritis, backache and fever. However, an anti-inflammatory effect and the specific mechanism of HM-R were not yet clear. In this study, we for the first time explored the anti-inflammatory of HM-R.

METHODS

The cytotoxicity of HM-R against RAW264.7 cells was evaluated using MTT assay. The inhibition of NO and PGE₂ production by HM-R was evaluated using Griess reagent and Prostaglandin E₂ ELISA Kit, respectively. The changes in mRNA or protein level following HM-R treatment were assessed by RT-PCR and Western blot analysis, respectively.

RESULTS

HM-R dose-dependently blocked LPS-induced NO and PGE₂ production. In addition, HM-R inhibited LPS-induced overexpression of iNOS, COX-2, IL-1β and IL-6 in RAW264.7 cells. HM-R inhibited LPS-induced NF-κB signaling activation through blocking IκB-α degradation and p65 nuclear accumulation. Furthermore, HM-R inhibited MAPK signaling activation by attenuating the phosphorylation of ERK1/2, p38 and JNK. HM-R increased nuclear accumulation of Nrf2 and HO-1 expression. However, NAC reduced the increased nuclear accumulation of Nrf2 and HO-1 expression by HM-R. In HPLC analysis, falcarinol was detected from HM-R as an anti-inflammatory compound.

CONCLUSIONS

These results indicate that HM-R may exert anti-inflammatory activity by inhibiting NF-κB and MAPK signaling, and activating ROS/Nrf2/HO-1 signaling. These findings suggest that HM-R has a potential as a natural material for the development of anti-inflammatory drugs.

Indazole-Cl inhibits hypoxia-induced cyclooxygenase-2 expression in vascular smooth muscle cells

Atherosclerosis is the most common root cause of arterial disease, such as coronary artery disease and carotid artery disease. Hypoxia is associated with the formation of macrophages and increased inflammation and is known to be present in lesions of atherosclerotic. Vascular smooth muscle cells (VSMCs) are one of the major components of blood vessels, and hypoxic conditions affect VSMC inflammation, proliferation and migration, which contribute to vascular stenosis and play a major role in the atherosclerotic process. Estrogen receptor (ER)-β is thought to play an important role in preventing the inflammatory response in VSMCs. In this report, we studied the anti-inflammatory effect of indazole (In)-Cl, an ERβ-specific agonist, under conditions of hypoxia. Expression of cyclooxygenase-2 reduced by hypoxia was inhibited by In-Cl treatment in VSMCs, and this effect was antagonized by an anti-estrogen compound. Additionally, the production of reactive oxygen species induced under conditions of hypoxia was reduced by treatment with In-Cl. Increased cell migration and invasion by hypoxia were also dramatically decreased following treatment with In-Cl. The increase in cell proliferation following treatment with platelet-derived growth factor was attenuated by In-Cl in VSMCs. RNA sequencing analysis was performed to identify changes in inflammation-related genes following In-Cl treatment in the hypoxic state. Our results suggest that ERβ is a potential therapeutic target for the suppression of hypoxia-induced inflammation in VSMCs.

Isoflavone ME-344 Disrupts Redox Homeostasis and Mitochondrial Function by Targeting Heme Oxygenase 1

ME-344 is a second-generation isoflavone with unusual cytotoxic properties that is in clinical testing in cancer. To identify targets that contribute to its anticancer activity and therapeutic index, we used lung cancer cell lines that are naturally sensitive or resistant to ME-344. Drug-induced apoptosis was linked with enhanced levels of reactive oxygen species and this initiated a nuclear erythroid factor 2-like 2 signaling response, downstream of which, heme oxygenase 1 (HO-1) was also found to be time-dependently inhibited by ME-344. ME-344 specifically bound to, and altered, HO-1 structure and increased HO-1 translocation from the rough endoplasmic reticulum to mitochondria, but only in drug-sensitive cells. These effects did not occur in either drug-resistant or primary lung fibroblasts with lower HO-1 basal levels. HO-1 was confirmed as a drug target by using surface plasmon resonance technology and through interaction with a clickable ME-344 compound (M2F) and subsequent proteomic analyses, showing direct binding of ME-344 with HO-1. Proteomic analysis showed that clusters of mitochondrial proteins, including voltage-dependent anion-selective channels, were also impacted by ME-344. Human lung cancer biopsies expressed higher levels of Nrf2 and HO-1 compared with normal tissues. Overall, our data show that ME-344 inhibits HO-1 and impacts its mitochondrial translocation. Other mitochondrial proteins are also affected, resulting in interference in tumor cell redox homeostasis and mitochondrial function. These factors contribute to a beneficial therapeutic index and support continued clinical development of ME-344. SIGNIFICANCE: A novel cytotoxic isoflavone is shown to inhibit heme oxygenase, a desirable yet elusive target that disrupts redox homeostasis causing cell death.

The role of endothelial dysfunction and oxidative stress in cerebrovascular diseases

Cerebrovascular diseases (CBD) are one of the most dangerous complications of atherosclerosis. The clinical consequences of CBD deeply impact quality of life and the prognosis of patients. Atherosclerosis is the main cause of CBD development. Hypertension, dyslipidemia, diabetes, smoking, obesity, and other risk factors explain the higher CBD incidence in the general population, as they are able to anticipate the clinical expression of atherosclerosis. These risk factors are effectively able to promote endothelial dysfunction which is the premise for the early, clinical expression of atherosclerosis. The mechanisms by which risk factors can influence the occurrence of CBD are different and not fully understood. The inflammatory background of atherosclerosis can explain a great part of it. In particular, the oxidative stress may promote the development of vascular lesions by negatively influencing biochemical cellular processes of the endothelium, thus predisposing the vascular tree to morphological and functional damages. The aim of this narrative review is to evaluate the role of endothelial dysfunction and oxidative stress in CBD development.

Sageretia thea Inhibits Inflammation through Suppression of NF-κB and MAPK and Activation of Nrf2/HO-1 Signaling Pathways in RAW264.7 Cells

Sageretia thea (S. thea) commonly known as Chinese sweet plum or Chinese bird plum has been used for treating hepatitis and fevers in Korea and China. S. thea has been reported to exert anti-oxidant, anticancer and anti-human immunodeficiency virus activity. However, there is little study on the anti-inflammatory activity of S. thea. Thus, we evaluated the anti-inflammatory effect of extracts of leaves (ST-L) and branches (ST-B) from Sageretia thea in LPS-stimulated RAW264.7 cells. ST-L and ST-B significantly inhibited the production of the pro-inflammatory mediators such as NO, iNOS, COX-2, IL-1[Formula: see text] and IL-6 in LPS-stimulated RAW264.7 cells. ST-L and ST-B blocked LPS-induced degradation of I[Formula: see text]B-[Formula: see text] and nuclear accumulation of p65, which resulted in the inhibition of NF-[Formula: see text]B activation in RAW264.7 cells. ST-L and ST-B also attenuated the phosphorylation of ERK1/2, p38 and JNK in LPS-stimulated RAW264.7 cells. In addition, ST-L and ST-B increased HO-1 expression in RAW264.7 cells, and the inhibition of HO-1 by ZnPP reduced the inhibitory effect of ST-L and ST-B against LPS-induced NO production in RAW264.7 cells. Inhibition of p38 activation and ROS elimination attenuated HO-1 expression by ST-L and ST-B, and ROS elimination inhibited p38 activation induced by ST-L and ST-B. ST-L and ST-B dramatically induced nuclear accumulation of Nrf2, but this was significantly reversed by the inhibition of p38 activation and ROS elimination. Collectively, our results suggest that ST-L and ST-B exerts potential anti-inflammatory activity by suppressing NF-[Formula: see text]B and MAPK signaling activation, and activating HO-1 expression through the nuclear accumulation of Nrf2 via ROS-dependent p38 activation. These findings suggest that ST-L and ST-B may have great potential for the development of anti-inflammatory drug to treat acute and chronic inflammatory disorders.

Cytotoxicity and Pro-/Anti-inflammatory Properties of Cinnamates, Acrylates and Methacrylates Against RAW264.7 Cells

BACKGROUND/AIM

Periodontitis is a chronic inflammatory disease linked to various systemic age-related conditions. It is known that α,β-unsaturated carbonyl compounds such as dietary cinnamates (β-phenyl acrylates) and related (meth)acrylates can have various positive and negative health effects, including cytotoxicity, allergic activity, pro-and anti-inflammatory activity, and anticancer activity. To clarify the anti-inflammatory properties of α,β-unsaturated carbonyl compounds without a phenolic group in the context of periodontal tissue inflammation and alveolar bone loss, we investigated the cytotoxicity and up-regulatory/down-regulatory effect of three trans-cinnamates (trans-cinnamic acid, methyl cinnamate, trans-cinnamaldehyde), two acrylates (ethyl acrylate, 2-hydroxyethyl acrylate), and three methacrylates (methyl methacrylate, 2-hydroxyethyl methacrylate, and triethyleneglycol dimethacrylate) using RAW264.7 cells.

MATERIALS AND METHODS

Cytotoxicity was determined using a cell counting kit (CCK-8) and mRNA expression was determined using real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Pro-inflammatory and anti-inflammatory properties were assessed in terms of expression of mRNAs for cyclo-oxygenase-2 (Cox2), nitric oxide synthase 2 (Nos2), tumor necrosis factor-alpha (Tnfa) and heme oxygenase 1 (Ho1).

RESULTS

The most cytotoxic compound was 2-hydroxyethyl acrylate, followed by ethyl acrylate and cinnamaldehyde (50% lethal cytotoxic concentration, LC₅₀=0.2-0.5 mM). Cox2 mRNA expression was up-regulated by cinnamaldehyde and 2-hydroxyethyl acrylate, particularly by the former. In contrast, the up-regulatory effect on Nos2 mRNA expression was in the order: cinnamaldehyde >> ethyl acrylate ≈ triethyleneglycol dimethacrylate >> methyl methacrylate ≈ methyl cinnamate. On the other hand, cinnamic acid and 2-hydroxyethyl methacrylate had no effect on gene expression. The two acrylates, but not cinnamates and methacrylates, up-regulated the expression of Ho1 mRNA at a non-cytotoxic concentration of 0.1 mM. Expression of Cox2, Nos2 and Tnfa mRNAs induced by Porphyromonas gingivalis lipopolysaccharide was greatly suppressed by cinnamaldehyde, methyl cinnamate and the two acrylates at 0.1 mM (p<0.05), and slightly, but significantly suppressed by cinnamic acid and methacrylates at 0.1-1 mM (p<0.05).

CONCLUSION

Cinnamaldehyde and acrylates exhibited both anti-inflammatory and pro-inflammatory properties, possibly due to their marked ability to act as Michael reaction acceptors, as estimated from the beta-carbon ¹³C-nuclear magnetic resonance spectra. Methyl cinnamate exhibited potent anti-inflammatory activity with less cytotoxicity and pro-inflammatory activity, suggesting that this compound may be useful for treatment of periodontal disease and related systemic diseases.

Activation of c-Met in cancer cells mediates growth-promoting signals against oxidative stress through Nrf2-HO-1

Any imbalance between reactive oxygen species (ROS) generation and the anti-oxidant capacity lead to cellular oxidative stress. Many chemotherapeutic agents mediate their cytotoxic functions through the generation of ROS. c-Met, a receptor tyrosine kinase, is over-expressed in renal cancer and plays very crucial role(s) in its growth and survival. Here, we show that c-Met activation protected renal cancer cells from ROS, oxidative stress and cytotoxicity induced by the anti-cancer agent sorafenib (used for renal cancer treatment); and it markedly attenuated sorafenib-induced DNA damage. Activated c-Met promoted the anti-apoptotic proteins (Bcl-2 and Bcl-xL) and inhibited apoptotic cleaved caspase-3. We found that the cytoprotective function of c-Met against sorafenib-induced ROS generation and apoptosis was mediated primarily through the activation of anti-oxidant Nrf2-HO-1. c-Met promoted the nuclear localization of Nrf2 and hindered its binding with the inhibitory protein Keap1. Silencing of Nrf2 attenuated the protective action of c-Met against sorafenib-induced oxidative stress. To evaluate the physiological significance of our findings, in a tumor xenograft model, we observed that a combination treatment with pharmacological inhibitors of c-Met and it's anti-oxidant downstream effecter HO-1 markedly reduced the growth of renal tumor in vivo; it increased the oxidative stress, DNA damage and apoptotic markers in the tumor xenografts, along with reduced tumor vessel density. Our observations indicate that the c-Met-Nrf2-HO-1 pathway plays a vital role in relieving ROS-mediated oxidative stress of renal tumors. Targeting this pathway can significantly increase the oxidative stress to promote apoptotic death of cancer cells.

Exogenous IL-19 attenuates acute ischaemic injury and improves survival in male mice with myocardial infarction

BACKGROUND AND PURPOSE

Myocardial infarction (MI) is one of the leading causes of death in China and often results in the development of heart failure. In this work, we tested the therapeutic role of Interleukin-19 (IL-19) in mice with MI and investigated the underlying molecular mechanism.

EXPERIMENTAL APPROACH

Mice were subjected to MI by ligation of left anterior descending coronary artery (LAD) and treated with IL-19 (10ng g^-1 ; i.p.).

KEY RESULTS

Protein expression of IL-19 and its receptor in myocardium were upregulated 24 hrs post-MI in male mice. IL-19 treatment decreased infarct and apoptosis in myocardium, accompanied by enhanced haem oxygenase-1 (HO-1) activities and reduced malondialdehyde (MDA) formation. Pretreatment with IL-19 upregulated HO-1 expression in cultured neonatal mouse ventricular myocytes and attenuated oxygen-glucose deprivation (OGD)-induced injuries in vitro. Furthermore, IL-19 preserved cardiac function and improved survival of mice with MI. IL-19 reduced inflammatory infiltrates and suppressed formation of TNF-α, IL-1β, and IL-6. More importantly, IL-19 inhibited polarization toward proinflammatory M1 macrophages and stimulated M2 macrophage polarization in myocardium of mice with MI. IL-19 enhanced protein levels of vascular endothelial growth factor (VEGF) and promoted angiogenesis in myocardium of mice with MI. In addition, IL-19 treatment increased DNA-binding of the transcription factor STAT3 in myocardium of mice with MI.

CONCLUSIONS AND IMPLICATIONS

Treatment with exogenous IL-19 attenuated acute ischemic injury and improved survival of mice with MI. The mechanisms underlying these effects involved induction of HO-1, M2 macrophage polarization, angiogenesis, and STAT3 activation.

Treatment with IL-19 improves locomotor functional recovery after contusion trauma to the spinal cord

BACKGROUND AND PURPOSE

IL-19 skews the immune response towards a Th2 type and appears to stimulate angiogenesis. In the current study, we tested if IL-19 treatment could reduce secondary injury and improve functional recovery after contusion spinal cord injury (SCI).

EXPERIMENTAL APPROACH

Firstly, mice were given a moderate-severe thoracic SCI at the T_9-10 level and expression of IL-19 and its receptor was measured in the injured spinal cord. Then SCI mice were treated with mouse recombinant IL-19 and its blocking antibody to investigate the therapeutic effect of IL-19.

KEY RESULTS

Protein expression of IL-19 and its receptor IL-20R1 and IL-20R2 was up-regulated in the injured spinal cord of mice. IL-19 treatment promoted the recovery of locomotor function dose-dependently and reduced loss of motor neurons and microglial and glial activation following SCI. Treatment of SCI mice with IL-19 attenuated macrophage accumulation, reduced protein levels of TNF-α and CCL2 and promoted Th2 response and M2 macrophage activation in the injured region. Treatment of SCI mice with IL-19 promoted angiogenesis through up-regulating VEGF in the injured region. Treatment of SCI mice with IL-19 up-regulated HO-1 expression and decreased oxidative stress in the injured region. The beneficial effect of IL-19 was abolished by coadministration of the blocking antibody. Additionally, IL-19 deficiency in mice delayed the recovery of locomotor function following SCI.

CONCLUSIONS AND IMPLICATIONS

IL-19 treatment reduced secondary injuries and improved locomotor functional recovery after contusion SCI, through diverse mechanisms including immune cell polarization, angiogenesis and anti-oxidative responses.

Expression of Cyclooxygenase-2, Nitric Oxide Synthase 2 and Heme Oxygenase-1 mRNA Induced by Bis-Eugenol in RAW264.7 Cells and their Antioxidant Activity Determined Using the Induction Period Method

BACKGROUND/AIM

To clarify the mechanisms responsible for the anti-inflammatory/proinflammatory activities of eugenol-related compounds, we investigated the cytotoxicity and up-regulatory/down-refgulatory effects of the biphenols curcumin, bis-eugenol, magnolol and honokiol, and the monophenols eugenol and isoeugenol, on major regulators of cyclooxygenase-2 (Cox-2), nitric oxide synthase 2 (Nos2) and heme oxygenase-1 (HO-1) mRNA in RAW264.7 cells.

MATERIALS AND METHODS

mRNA expression was investigated using real-time reverse transcriptase-polymerase chain reaction (RT-PCR), and the theoretical parameters were calculated using the DFT/B3LYP/6-31* method. Also, the antioxidant activity of eugenol-related compounds in combination with 2-mercapto-1-methylimidazole (MMI, as a model for glutathione (GSH)) was investigated using the induction period method for polymerization of methyl methacrylate initiated by benzoyl peroxide (BPO).

RESULTS

The cytotoxicity of eugenol-related compounds showed a linear relationship with their softness (σ) and electrophilicity (ω). At a concentration of 50 μM, biphenols except for bis-eugenol elicited the expression of mRNA for both Cox-2 and Nos2, but monophenols did not. In contrast, bis-eugenol elicited Cox-2 gene expression, but down-regulated Nos2 gene expression. bis-Eugenol alone induced the expression of HO-1 mRNA, and when combined with MMI it showed a potent antagonistic effect on BPO-induced antioxidant activity. The ability of methoxyphenols to inhibit LPS-stimulated Cox-2 gene expression declined in the order curcumin >> isoeugenol > bis-eugenol >> eugenol, and the rank of ability was related to their ω value.

CONCLUSION

Most eugenol-related compounds had proinflammatory activity at high concentrations. However, they had also anti-inflammatory activity at lower concentrations. Eugenol-related compounds may exert antioxidant and anti-inflammatory activity in LPS-stimulated RAW264.7 cells possibly by inhibiting the activation of nuclear factor-kappa B (Nf-ĸB), whereas bis-eugenol requires induction of HO-1 expression. bis-Eugenol as well as curcumin, may have anti-inflammatory and anticancer therapeutic applications.

IL-19 and Other IL-20 Family Member Cytokines in Vascular Inflammatory Diseases

Cardiovascular disease remains a major medical and socioeconomic burden in developed and developing countries and will increase with an aging and increasingly sedentary society. Many vascular diseases and atherosclerotic vascular disease, in particular, are essentially inflammatory disorders, involving multiple cell types. Communication between these cells is initiated and sustained by a complex network of cytokines and their receptors. The interleukin (IL)-20 family members, IL-19, IL-20, IL-22, and IL-24, initiate, sustain, and drive the progression of vascular disease. They are important in vascular disease as they facilitate a bidirectional cross-talk between resident vascular cells with immune cells. These cytokines are grouped into the same family based on shared common receptor subunits and signaling pathways. This communication is varied and can result in exacerbation, attenuation, and even repair of the vasculature. We will briefly review what is known about IL-20, IL-22, and IL-24 in cardiovascular biology. Because IL-19 is the most studied member of this family in terms of its role in vascular pathophysiological processes, the major emphasis of this review will focus on the expression and atheroprotective roles of IL-19 in vascular inflammatory disease.

Isoegomaketone Upregulates Heme Oxygenase-1 in RAW264.7 Cells via ROS/p38 MAPK/Nrf2 Pathway

Isoegomaketone (IK) was isolated from Perilla frutescens, which has been widely used as a food in Asian cuisine, and evaluated for its biological activity. We have already confirmed that IK induced the HO-1 expression via Nrf2 activation in RAW264.7 cells. In this study, we investigated the effect of IK on the mechanism of HO-1 expression. IK upregulated HO-1 mRNA and protein expression in a dose dependent manner. The level of HO-1 mRNA peaked at 4 h after 15 μM IK treatment. To investigate the mechanisms of HO-1 expression modulation by IK, we used pharmacological inhibitors for the protein kinase C (PKC) family, PI3K, and p38 MAPK. IK-induced HO-1 mRNA expression was only suppressed by SB203580, a specific inhibitor of p38 MAPK. ROS scavengers (N-acetyl-L-cysteine, NAC, and glutathione, GSH) also blocked the IK-induced ROS production and HO-1 expression. Furthermore, both NAC and SB203580 suppressed the IK-induced Nrf2 activation. In addition, ROS scavengers suppressed other oxidative enzymes such as catalase (CAT), glutathione S-transferase (GST), and NADH quinone oxidoreductase (NQO-1) in IK-treated RAW264.7 cells. Taken together, it can be concluded that IK induced the HO-1 expression through the ROS/p38 MAPK/ Nrf2 pathway in RAW264.7 cells.

MicroRNA expression profiling of human blood monocyte subsets highlights functional differences

Within human blood there are two subsets of monocytes that can be identified by differential expression of CD16. Although numerous phenotypic and functional differences between the subsets have been described, little is known of the mechanisms underlying the distinctive properties of the two subsets. MicroRNAs (miRNAs) are small non-coding RNAs that can regulate gene expression through promoting mRNA degradation or repressing translation, leading to alterations in cellular processes. Their potential influence on the functions of monocyte subsets has not been investigated. In this study, we employed microarray analysis to define the miRNA expression profile of human monocyte subsets. We identified 66 miRNAs that were differentially expressed (DE) between CD16(+) and CD16(-) monocytes. Gene ontology analysis revealed that the predicted targets of the DE miRNAs were predominantly associated with cell death and cellular movement. We validated the functional impacts of selected DE miRNAs in CD16(-) monocytes, over-expression of miR-432 significantly increases apoptosis, and inhibiting miR-19a significantly reduces cell motility. Furthermore, we found that miR-345, another DE miRNA directly targets the transcription factor RelA in monocytes, which resulted in the differential expression of RelA in monocyte subsets. This implicates miR-345 indirect regulation of many genes downstream of RelA, including important inflammatory mediators. Together, our data show that DE miRNAs could contribute substantially to regulating the functions of human blood monocytes.

Src/STAT3-dependent heme oxygenase-1 induction mediates chemoresistance of breast cancer cells to doxorubicin by promoting autophagy

Chemotherapeutic resistance in breast cancer, whether acquired or intrinsic, remains a major clinical obstacle. Thus, increasing tumor cell sensitivity to chemotherapeutic agents will be helpful in improving the clinical management of breast cancer. In the present study, we found an induction of HO-1 expression in doxorubicin (DOX)-treated MDA-MB-231 human breast adenocarcinoma cells, which showed insensitivity to DOX treatment. Knockdown HO-1 expression dramatically upregulated the incidence of MDA-MB-231 cell death under DOX treatment, indicating that HO-1 functions as a critical contributor to drug resistance in MDA-MB-231 cells. We further observed that DOX exposure induced a cytoprotective autophagic flux in MDA-MB-231 cells, which was dependent on HO-1 induction. Moreover, upregulation of HO-1 expression required the activation of both signal transducer and activator of transcription (STAT)3 and its upstream regulator, protein kinase Src. Abrogating Src/STAT3 pathway activation attenuated HO-1 and autophagy induction, thus increasing the chemosensitivity of MDA-MB-231 cells. Therefore, we conclude that Src/STAT3-dependent HO-1 induction protects MDA-MB-231 breast cancer cells from DOX-induced death through promoting autophagy. In the following study, we further demonstrated the contribution of Src/STAT3/HO-1/autophagy pathway activation to DOX resistance in another breast cancer cell line, MDA-MB-468, which bears a similar phenotype to MDA-MB-231 cells. Therefore, activation of Src/STAT3/HO-1/autophagy signaling pathway might play a general role in protecting certain subtypes of breast cancer cells from DOX-induced cytotoxicity. Targeting this signaling event may provide a potential approach for overcoming DOX resistance in breast cancer therapeutics.

Human mesenchymal stromal cells suppress T-cell proliferation independent of heme oxygenase-1

Mesenchymal stromal cells deploy immune suppressive properties amenable for use as cell therapy for inflammatory disorders. It is now recognized that mesenchymal stromal cells necessitate priming with an inflammatory milieu, in particular interferon-γ, to exert augmented immunosuppressive effects. It has been recently suggested that the heme-catabolizing enzyme heme oxygenase-1 is an essential component of the mesenchymal stromal cell-driven immune suppressive response. Because mesenchymal stromal cells upregulate indoleamine 2,3-dioxygenase expression on interferon-γ priming and indoleamine 2,3-dioxygenase requires heme as a cofactor for optimal catabolic function, we investigated the potential antagonism of heme oxygenase-1 activity on indoleamine 2, 3-dioxygenase and the impact on mesenchymal stromal cell immune plasticity. We herein sought to evaluate the molecular genetic effect of cytokine priming on human mesenchymal stromal cell heme oxygenase-1 expression and its functional role in differentially primed mesenchymal stromal cells. Contrary to previous reports, messenger RNA and protein analyses demonstrated that mesenchymal stromal cells derived from normal subjects (n = 6) do not express heme oxygenase-1 at steady state or after interferon-γ, tumor necrosis factor-α, and/or transforming growth factor-β priming. Pharmacological inhibition of heme oxygenase-1 with the use of tin protoporphyrin did not significantly abrogate the ability of mesenchymal stromal cells to suppress T-cell proliferation in vitro. Overall, these results unequivocally demonstrate that under steady state and after cytokine priming, human mesenchymal stromal cells immunoregulate T-cell proliferation independent of heme oxygenase-1.

Astrocytes produce IL-19 in response to bacterial challenge and are sensitive to the immunosuppressive effects of this IL-10 family member

There is growing appreciation that resident glial cells can initiate and/or regulate inflammation following trauma or infection in the central nervous system (CNS). We have previously demonstrated the ability of microglia and astrocytes to respond to bacterial pathogens or their products by rapid production of inflammatory mediators, followed by the production of the immunosuppressive cytokine interleukin (IL)−10. IL-19, another member of the IL-10 family of cytokines, has been studied in the context of a number of inflammatory conditions in the periphery and is known to modulate immune cell activity. In the present study, we demonstrate the constitutive and/or inducible expression of IL-19 and its cognate receptor subunits, IL-19Rα and IL-19Rβ (also known as IL-20R1 and IL-20R2, and IL-20RA and IL-20RB), in mouse brain tissue, and by primary murine and human astrocytes. We also provide evidence for the presence of a novel truncated IL-19Rα transcript variant in mouse brain tissue, but not glial cells, that shows reduced expression following bacterial infection. Importantly, IL-19R functionality in glia is indicated by the ability of IL-19 to regulate signaling component expression in these cells. Furthermore, while IL-19 itself had no effect on glial cytokine production, IL-19 treatment of bacterially infected or Toll-like receptor ligand stimulated astrocytes significantly attenuated pro-inflammatory cytokine production. The bacterially induced production of IL-19 by these resident CNS cells, the constitutive expression of its cognate receptor subunits, and the immunomodulatory effects of this cytokine, suggest a novel mechanism by which astrocytes can regulate CNS inflammation.

IL-19 is a component of the pathogenetic IL-23/IL-17 cascade in psoriasis

Psoriasis is a common chronic inflammatory disease with characteristic skin alterations and functions as a model of immune-mediated disorders. Cytokines have a key role in psoriasis pathogenesis. Here, we demonstrated that out of 30 individually quantified cytokines, IL-19 showed the strongest differential expression between psoriatic lesions and healthy skin. Cutaneous IL-19 overproduction was reflected by elevated IL-19 blood levels that correlated with psoriasis severity. Accordingly, anti-psoriatic therapies substantially reduced both cutaneous and systemic IL-19 levels. IL-19 production was induced in keratinocytes by IL-17A and was further amplified by tumor necrosis factor-α and IL-22. Among skin cells, keratinocytes were found to be important targets of IL-19. IL-19 alone, however, regulated only a few keratinocyte functions. While increasing the production of S100A7/8/9 and, to a moderate extent, also IL-1β, IL-20, chemokine C-X-C motif ligand 8, and matrix metalloproteinase 1, IL-19 had no clear influence on the differentiation, proliferation, or migration of these cells. Importantly, IL-19 amplified many IL-17A effects on keratinocytes, including the induction of β-defensins, IL-19, IL-23p19, and T helper type 17-cell- and neutrophil-attracting chemokines. In summary, IL-19 as a component of the IL-23/IL-17 axis strengthens the IL-17A action and might be a biomarker for the activity of this axis in chronic inflammatory disorders.

IL-19 reduces ligation-mediated neointimal hyperplasia by reducing vascular smooth muscle cell activation

We tested the hypothesis that IL-19, a putative member of the type 2 helper T-cell family of anti-inflammatory interleukins, can attenuate intimal hyperplasia and modulate the vascular smooth muscle cell (VSMC) response to injury. Ligated carotid artery of IL-19 knockout (KO) mice demonstrated a significantly higher neointima/intima ratio compared with wild-type (WT) mice (P = 0.04). More important, the increased neointima/intima ratio in the KO could be reversed by injection of 10 ng/g per day recombinant IL-19 into the KO mouse (P = 0.04). VSMCs explanted from IL-19 KO mice proliferated significantly more rapidly than WT. This could be inhibited by addition of IL-19 to KO VSMCs (P = 0.04 and P < 0.01). IL-19 KO VSMCs migrated more rapidly compared with WT (P < 0.01). Interestingly, there was no type 1 helper T-cell polarization in the KO mouse, but there was significantly greater leukocyte infiltrate in the ligated artery in these mice compared with WT. IL-19 KO VSMCs expressed significantly greater levels of inflammatory mRNA, including IL-1β, tumor necrosis factor α, and monocyte chemoattractant protein-1 in response to tumor necrosis factor α stimulation (P < 0.01 for all). KO VSMCs expressed greater adhesion molecule expression and adherence to monocytes. Together, these data indicate that IL-19 is a previously unrecognized counterregulatory factor for VSMCs, and its expression is an important protective mechanism in regulation of vascular restenosis.

Inhibition of calpain reduces oxidative stress and attenuates endothelial dysfunction in diabetes

Aims

The present study was to investigate the role of calpain in reactive oxygen species (ROS) production in endothelial cells and endothelium-dependent vascular dysfunction under experimental conditions of diabetes.

Methods and results

Exposure to high glucose activated calpain, induced apoptosis and reduced nitric oxide (NO) production without changing eNOS protein expression, its phosphorylation and dimers formation in primary human umbilical vein endothelial cells (HUVECs). These effects of high glucose correlated with intracellular ROS production and mitochondrial superoxide generation. Selectively scavenging mitochondrial superoxide increased NO production in high glucose-stimulated HUVECs. Inhibition of calpain using over-expression of calpastatin or pharmacological calpain inhibitor prevented high glucose-induced ROS production, mitochondrial superoxide generation and apoptosis, which were concurrent with an elevation of NO production in HUVECs. In mouse models of streptozotocin-induced type-1 diabetes and OVE26 type-1 diabetic mice, calpain activation correlated with an increase in ROS production and peroxynitrite formation in aortas. Transgenic over-expression of calpastatin reduced ROS production and peroxynitrite formation in diabetic mice. In parallel, diabetes-induced reduction of endothelium-dependent relaxation in aortic ring was reversed by over-expression of calpastatin in mouse models of diabetes. However, the protective effect of calpastatin on endothelium-dependent relaxation was abrogated by eNOS deletion in diabetic mice.

Conclusions

This study suggests that calpain may play a role in vascular endothelial cell ROS production and endothelium-dependent dysfunction in diabetes. Thus, calpain may be an important therapeutic target to overcome diabetes-induced vascular dysfunction.

Dietary quercetin attenuates oxidant-induced endothelial dysfunction and atherosclerosis in apolipoprotein E knockout mice fed a high-fat diet: a critical role for heme oxygenase-1

Several lines of evidence indicate that quercetin, a polyphenol derived in the diet from fruit and vegetables, contributes to cardiovascular health. We aimed to investigate the effects of dietary quercetin on endothelial function and atherosclerosis in mice fed a high-fat diet. Wild-type C57BL/6 (WT) and apolipoprotein E gene knockout (ApoE(-/-)) mice were fed: (i) a high-fat diet (HFD) or (ii) a HFD supplemented with 0.05% w/w quercetin (HFD+Q), for 14 weeks. Compared with animals fed HFD, HFD+Q attenuated atherosclerosis in ApoE(-/-) mice. Treatment with the HFD+Q significantly improved endothelium-dependent relaxation of aortic rings isolated from WT but not ApoE(-/-) mice and attenuated hypochlorous acid-induced endothelial dysfunction in aortic rings of both WT and ApoE(-/-) mice. Mechanistic studies revealed that HFD+Q significantly improved plasma F2-isoprostanes, 24h urinary nitrite, and endothelial nitric oxide synthase activity, and increased heme oxygenase-1 (HO-1) protein expression in the aortas of both WT and ApoE(-/-) mice (P<0.05). HFD+Q also resulted in small changes in plasma cholesterol (P<0.05 in WT) and plasma triacylglycerols (P<0.05 in ApoE (-/-)mice). In a separate experiment, quercetin did not protect against hypochlorite-induced endothelial dysfunction in arteries obtained from heterozygous HO-1 gene knockout mice with low expression of HO-1 protein. Quercetin protects mice fed a HFD against oxidant-induced endothelial dysfunction and ApoE(-/-) mice against atherosclerosis. These effects are associated with improvements in nitric oxide bioavailability and are critically related to arterial induction of HO-1.

Cobalt protoporphyrin induces HO-1 expression mediated partially by FOXO1 and reduces mitochondria-derived reactive oxygen species production

Background

Reactive oxygen species arise in the mitochondria as byproducts of respiration and oxidase activity and have important roles in many physiological and pathophysiological conditions. The level of reactive oxygen species is regulated by a number of enzymes and physiological antioxidants, including HO-1, Sod2, catalase and COX-2, etc. And HO-1 against oxidative stress requires an increase in stress-responsive genes, such as Sod2 and catalase. Especially for the activity of HO-1, cobalt protoporphyrin is known to be a potent and effective inducer in many tissues. The transcription factor, FOXO1 is resistant to oxidative stress through downregulating reactive oxygen species production. Previous study showed that FOXO1 induces HO-1 expression by binding to HO-1 promoter. The question whether cobalt protoporphyrin induces HO-1 expression mediated by FOXO1 and subsequently lessens reactive oxygen species production remains to be elucidated.

Results

Cobalt protoporphyrin enhances the expression of FOXO1 and facilitates FOXO1 binding to HO-1 promoter and increasing its transcriptional activity without influencing the FOXO1 protein stability. CoPP induces HO-1 and other oxidative stress-responsive genes expression, such as catalase, cytochrome c, Sod2, and COX-2, and decreases mitochondria-derived reactive oxygen species production, which are mediated partially by FOXO1.

Conclusions

Cobalt protoporphyrin induces HO-1 and other oxidative stress-responsive genes expression mediated partially by FOXO1, and has an important role in reducing cellular reactive oxygen species level. Cobalt protoporphyrin may be a more promising therapeutic agent to upregulate some antioxidantive genes.

Heat shock protein 32/heme oxygenase-1 protects mouse Sertoli cells from hyperthermia-induced apoptosis by CO activation of sGC signalling pathways

Heat shock protein 32 (Hsp32)/heme oxygenase-1 (HO-1) may be a key enzyme for the protection of cells against stress. Its anti-apoptotic effect has been attributed to its product, carbon monoxide (CO), in many types of cells. However, whether its anti-apoptotic mechanism plays a role in Sertoli cells (SCs) is not yet clear. We hypothesise that Hsp32/HO-1 and CO generated from it provide survival advantages in SCs by preventing apoptosis under heat exposure. After treatment of cultured SCs with hyperthermia and/or Hsp32/HO-1 activater hemin, apoptosis was measured valuated by annexin V-FITC and caspase-3 activation. We have also analysed the Hsp32/HO-1-derived CO content of cultured media and cyclic guanosine monophosphate (cGMP) production by enzyme-linked immunosorbent assay (ELISA). Hyperthermia induced SCs apoptosis, while preincubation with hemin suppressed SC hyperthermia-induced apoptosis. Hyperthermia and/or hemin increase Hsp32/HO-1 gene expression and the production of CO, which, in turn, stimulates the generation of cGMP. The results suggest that Hsp32/HO-1 is a protective factor in heat-stressed SCs, and that CO generated from Hsp32/HO-1 is involved in the anti-apoptotic pathway.

Heme oxygenase-1 and inflammation in experimental right ventricular failure on prolonged overcirculation-induced pulmonary hypertension

Heme oxygenase (HO)-1 is a stress response enzyme which presents with cardiovascular protective and anti-inflammatory properties. Six-month chronic overcirculation-induced pulmonary arterial hypertension (PAH) in piglets has been previously reported as a model of right ventricular (RV) failure related to the RV activation of apoptotic and inflammatory processes. We hypothesized that altered HO-1 signalling could be involved in both pulmonary vascular and RV changes. Fifteen growing piglets were assigned to a sham operation (n = 8) or to an anastomosis of the left innominate artery to the pulmonary arterial trunk (n = 7). Six months later, hemodynamics was evaluated after closure of the shunt. After euthanasia of the animals, pulmonary and myocardial tissue was sampled for pathobiological evaluation. Prolonged shunting was associated with a tendency to decreased pulmonary gene and protein expressions of HO-1, while pulmonary gene expressions of interleukin (IL)-33, IL-19, intercellular adhesion molecule (ICAM)-1 and -2 were increased. Pulmonary expressions of constitutive HO-2 and pro-inflammatory tumor necrosis factor (TNF)-α remained unchanged. Pulmonary vascular resistance (evaluated by pressure/flow plots) was inversely correlated to pulmonary HO-1 protein and IL-19 gene expressions, and correlated to pulmonary ICAM-1 gene expression. Pulmonary arteriolar medial thickness and PVR were inversely correlated to pulmonary IL-19 expression. RV expression of HO-1 was decreased, while RV gene expressions TNF-α and ICAM-2 were increased. There was a correlation between RV ratio of end-systolic to pulmonary arterial elastances and RV HO-1 expression. These results suggest that downregulation of HO-1 is associated to PAH and RV failure.

Upregulation of heat shock protein 32 in Sertoli cells alleviates the impairments caused by heat shock-induced apoptosis in mouse testis

Heat stress results in apoptosis in testicular germ cells. A small heat shock protein (hsp), hsp32, is induced by heat stress in the testis, but little is known about its definitive function in physiological processes. To clarify the underlying role of hsp32, hsp32 expression and related signals in the heat shock pathway were analysed in mouse testes and Sertoli cells after heat stress in vivo and in vitro; meanwhile, expression of hsp32 was silenced only in the Sertoli cells using three different small interfering RNAs (siRNAs) to further verify the functional role of hsp32 in Sertoli cells, and hsp32-derived carbon monoxide (CO) contents in cultured media were analysed to clarify whether hsp32-derived CO involve in the apoptosis regulation mechanisms. The results from the in vivo experiment showed that the high expression levels of hsp32 (P < 0.05) were observed whether chronic, moderate or acute, transient heat exposure. The in vitro experiment showed that acute, transient heat exposure resulted in increases in Sertoli cells apoptosis (P < 0.01), the expression of hsp32 and caspase-3 activity; hsp32-siRNA knockdown of hsp32 expression resulted in upregulated apoptosis (P < 0.01) and caspase-3 activity (P < 0.01) in the Sertoli cells and hyperthermia increases CO (P < 0.01) release by Sertoli cells. The results suggested that upregulating hsp32 in Sertoli cells inhibits caspase-3 activity and alleviates heat-induced impairments in mouse testis; hsp32-derived CO may involve in the regulation mechanism.

Interleukin-19 in breast cancer

Inflammatory cytokines within the tumor microenvironment are linked to progression in breast cancer. Interleukin- (IL-) 19, part of the IL-10 family, contributes to a range of diseases and disorders, such as asthma, endotoxic shock, uremia, psoriasis, and rheumatoid arthritis. IL-19 is expressed in several types of tumor cells, especially in squamous cell carcinoma of the skin, tongue, esophagus, and lung and invasive duct carcinoma of the breast. In breast cancer, IL-19 expression is correlated with increased mitotic figures, advanced tumor stage, higher metastasis, and poor survival. The mechanisms of IL-19 in breast cancer have recently been explored both in vitro and in vivo. IL-19 has an autocrine effect in breast cancer cells. It directly promotes proliferation and migration and indirectly provides a microenvironment for tumor progression, which suggests that IL-19 is a prognostic marker in breast cancer and that antagonizing IL-19 may have therapeutic potential.

IL-19 and IL-20 genes polymorphisms and haplotype analysis in a vesicoureteral reflux population

Vesicoureteral reflux (VUR) is a common childhood problem, causing renal wounds and escalating the risk of renal deficiency and hypertension. A vast literature exists suggesting that genetic variations play a significant role in the pathogenesis of VUR. The aim of the present study was to estimate whether genetic polymorphisms of IL-19 (GC rs2243158, AT rs2243158) and IL-20 (AG rs2981573, TG rs2981572) genes are involved in the development of VUR.

MATERIALS AND METHODS

The tetra amplification mutation refractory system-polymerase chain reaction (Tetra-ARMS PCR) was applied for analyzing four polymorphic sites of IL-19 (GC rs2243158, AT rs2243158) and IL-20 (AG rs2981573, TG rs2981572) genes in 110 healthy controls and 124 VUR children.

RESULTS

A significant association was found between the combined genotypes of IL19GC+CC and IL20TG+GG and increased risk of VUR (OR = 1.90, 95% CL, 1.06-3.41; OR=1.87, 95% CL, 1.06-3.29, respectively). The frequency of allele G in both sites of IL-20 (IL20AG rs2981573 and IL20TG, rs2981572) showed a statistically significant difference (p = 0.01) between cases and controls in comparison with the wild type. The combined haplotype analysis of IL-19 and IL-20 polymorphic sites revealed that HT2, HT3 and HT5 haplotypes marginally increased the risk of VUR, but not statistically significantly. Gene-gene interaction data of IL-19 (GC rs2243158, AT rs2243158) and IL-20 (AG rs2981573, TG rs2981572) in various genotype patterns highlighted the fact that most of the genotype combinations increased the risk of disease insignificantly.

CONCLUSION

This is the first evidence regarding IL-19 and IL-20 cytokine genes polymorphism and risk of VUR, suggesting the need for further study with large sample size and in different populations to confirm the presented data.

Pro- and Anti-Inflammatory Cytokine Networks in Atherosclerosis

Despite advances in prevention and treatment, atherosclerotic vascular disease continues to account for significant morbidity, mortality, and economic burden in the western world. Our current understanding of this disease presents atherosclerosis as a chronic inflammatory process involving multiple cell types in various stages of activation, apoptosis, and necrosis. These cells include monocyte/macrophage, dendritic cells, lymphocytes, endothelial cells, and vascular smooth muscle cells. Activation of these cells and their processes is initiated and sustained by a complex network of soluble factors termed cytokines. Cytokines are produced and recognized by both inflammatory and resident vascular cells, allowing crosstalk between these two systems. Cytokines also regulate the phenotype of many of these cell types. Recognizing functions of these cytokines and their effects on cells which populate atherosclerotic plaque is key to uncovering targets of therapeutic intervention. This paper will present recent studies which describe the cellular protagonists of atherosclerosis and the role they play in formation of atherosclerotic plaque. It will also describe the cytokines which have been identified as produced by and directly affecting dysfunction of these cells. Because atherosclerosis is considered an inflammatory condition, emphasis will be placed on inflammatory cytokines and their effects on atherogenesis. We will conclude with new directions in therapeutic strategies and points of emphasis for future research.

Molecular signatures in response to Isoliquiritigenin in lymphoblastoid cell lines

Isoliquiritigenin (ISL) has been known to induce cell cycle arrest and apoptosis of various cancer cells. However, genetic factors regulating ISL effects remain unclear. The aim of this study was to identify the molecular signatures involved in ISL-induced cell death of EBV-transformed lymphoblastoid cell lines (LCLs) using microarray analyses. For gene expression and microRNA (miRNA) microarray experiments, each of 12 LCL strains was independently treated with ISL or DMSO as a vehicle control for a day prior to total RNA extraction. ISL treatment inhibited cell proliferation of LCLs in a dose-dependent manner. Microarray analysis showed that ISL-treated LCLs represented gene expression changes in cell cycle and p53 signaling pathway, having a potential as regulators in LCL survival and sensitivity to ISL-induced cytotoxicity. In addition, 36 miRNAs including five miRNAs with unknown functions were differentially expressed in ISL-treated LCLs. The integrative analysis of miRNA and gene expression profiles revealed 12 putative mRNA-miRNA functional pairs. Among them, miR-1207-5p and miR-575 were negatively correlated with p53 pathway- and cell cycle-associated genes, respectively. In conclusion, our study suggests that miRNAs play an important role in ISL-induced cytotoxicity in LCLs by targeting signaling pathways including p53 pathway and cell cycle.

Anti-inflammatory effects of interleukin-19 in vascular disease

Despite aggressive dietary modification, lipid-lowering medications, and other interventional medical therapy, vascular disease continues to be a leading cause of mortality in the western world. It is a significant medical and socioeconomic problem contributing to mortality of multiple diseases including myocardial infarction, stroke, renal failure, and peripheral vascular disease. Morbidity and mortality of vascular disease are expected to worsen with the increasing number of patients with comorbid conditions such as obesity, metabolic syndrome, and diabetes mellitus type 2. Vascular diseases such as atherosclerosis, restenosis, and allograft vasculopathy are recognized to be driven by inflammation, and as such, cytokines which mediate inflammation not only represent important targets of rational therapy, but also can be considered as possible therapeutic modalities themselves. In this paper, we will examine the role of inflammatory cytokines and lymphocyte T(h)1/T(h)2 polarity in vascular inflammation, with a focus on atherosclerotic vascular disease. We will then introduce a recently described T(h)2 interleukin, interleukin-19 (IL-19), as a previously unrecognized mediator of vascular inflammatory disorders. We will review our current understanding of this interleukin in health and disease and present the possibility that IL-19 could represent a potential therapeutic to combat vascular inflammatory disease.

Involvement of Heme Oxygenase-1 Participates in Anti-Inflammatory and Analgesic Effects of Aqueous Extract of Hibiscus taiwanensis

Anti-inflammatory effects of the aqueous extract of Hibiscus taiwanensis (AHT) were used in lipopolysaccharide (LPS-)stimulated mouse macrophage RAW264.7 cells and carrageenan (Carr-)induced mouse paw edema model. When RAW264.7 macrophages were treated with AHT together with LPS, a concentration-dependent inhibition of nitric oxide (NO), tumor necrosis factor (TNF-α), and prostaglandin E2 (PGE(2)) levels productions were detected. Western blotting revealed that AHT blocked protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and elevated heme oxygenase-1 (HO-1), significantly. In the animal test, AHT decreased the paw edema at the 4th and the 5th h after Carr administration, and it increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the paw tissue. We also demonstrated AHT decreased the NO, TNF-α, and PGE2 levels on the serum level at the 5th h after the Carr injection. Western blotting revealed that AHT decreased Carr-induced iNOS, and COX-2, and increased HO-1 expressions at the 5th h in the edema paw. These findings demonstrated that AHT has excellent anti-inflammatory activities in vitro and in vivo and thus it has great potential to be used as a source for natural health products.