Role of the Jak/STAT pathway in the regulation of interleukin-8 transcription by oxidized phospholipids in vitro and in atherosclerosis in vivo

Inflammatory Pathways in Coronary Artery Disease: Which Ones to Target for Secondary Prevention?

Coronary artery disease (CAD), the build-up of atherosclerotic plaques on the wall of blood vessels, causes adverse cardiovascular events. Secondary prevention focuses on treating patients with existing plaques to prevent disease progression. Recent studies have shown that inflammation is an independent risk factor that drives disease progression, and targeting inflammation could be an effective therapeutic strategy for secondary prevention. In this review, we highlighted the roles of several inflammatory pathways in rupture and erosion, two major processes through which established plaques lead to adverse cardiovascular events. In the past 15 years, numerous clinical trials have tested the therapeutic potential of targeting these pathways, including neutralizing inflammatory cytokines and blocking signaling transduction of the inflammatory pathways. Only colchicine was approved for clinical use in patients with CAD. This is primarily due to the multifaceted roles of inflammatory pathways in disease progression. Commonly used pre-clinical models provided robust information for the onset of early disease but limited understanding of the inflammatory network in established plaques. This review will summarize lessons learned from successful and failed clinical trials to advocate for assessing inflammation in established plaques before designing therapeutics for secondary prevention.

Immunological perspectives on atherosclerotic plaque formation and progression

Atherosclerosis serves as the primary catalyst for numerous cardiovascular diseases. Growing evidence suggests that the immune response is involved in every stage of atherosclerotic plaque evolution. Rapid, but not specific, innate immune arms, including neutrophils, monocytes/macrophages, dendritic cells (DCs) and other innate immune cells, as well as pattern-recognition receptors and various inflammatory mediators, contribute to atherogenesis. The specific adaptive immune response, governed by T cells and B cells, antibodies, and immunomodulatory cytokines potently regulates disease activity and progression. In the inflammatory microenvironment, the heterogeneity of leukocyte subpopulations plays a very important regulatory role in plaque evolution. With advances in experimental techniques, the fine mechanisms of immune system involvement in atherosclerotic plaque evolution are becoming known. In this review, we examine the critical immune responses involved in atherosclerotic plaque evolution, in particular, looking at atherosclerosis from the perspective of evolutionary immunobiology. A comprehensive understanding of the interplay between plaque evolution and plaque immunity provides clues for strategically combating atherosclerosis.

The double-edged nature of nicotine: toxicities and therapeutic potentials

Nicotine is the primary addictive component of cigarette smoke and is associated with various smoking-related diseases. However, recent research has revealed its broader cognitive-enhancing and anti-inflammatory properties, suggesting its potential therapeutic applications in several conditions. This review aims to examine the double-edged nature of nicotine, encompassing its positive and negative effects. We provide a concise overview of the physiochemical properties and pharmacology of nicotine, including insights into nicotine receptors. Therefore, the article is divided into two main sections: toxicity and therapeutic potential. We comprehensively explored nicotine-related diseases, focusing on specific signaling pathways and the underlying mechanisms that contribute to its effects. Furthermore, we addressed the current research challenges and future development perspectives. This review aims to inspire future researchers to explore the full medical potential of nicotine, which holds significant promise for the clinical management of specific diseases.

Dendrobine regulates STAT3 to attenuate mitochondrial dysfunction and senescence in vascular endothelial cells triggered by oxidized low-density lipoprotein

Our previous studies have highlighted the potential therapeutic efficacy of dendrobine, an alkaloid, in atherosclerosis (AS), nevertheless, the underlying mechanism remains unclear. This study employs a combination of network pharmacology and in vitro experiments to explore the regulatory pathways involved. Through network pharmacology, the biological function for intersection targets between dendrobine and AS were identified. Molecular docking was conducted to investigate the interaction between the dominant target and dendrobine. Human umbilical vein endothelial cells (HUVECs) were treated with oxidized low-density lipoprotein (ox-LDL) to mimic AS, and the effects of dendrobine on cell viability, lipid deposition, mitochondrial function, and cellular senescence were evaluated. Subsequently, cells were treated with the mitophagy inhibitor Mdivi-1 and the STAT3 agonist colivelin to assess the role of mitophagy and STAT3 signaling in dendrobine regulation. Intersection targets were associated with biological processes, including reactive oxygen species production. Dendrobine attenuated the effects of ox-LDL treatment on HUVECs, mitigating changes in cell activity, lipid deposition, mitochondrial function, and cellular senescence. Both Mdivi-1 and colivelin treatments resulted in decreased cell viability and increased cellular senescence, with colivelin suppressing mitophagy. Cotreatment with Mdivi-1 and colivelin further aggravated cellular senescence and inhibited FoxO signaling. Together, this study indicated that dendrobine regulated the STAT3/FoxO signaling pathway, alleviating mitochondrial dysfunction and cellular senescence. This study contributes valuable insights to the potential clinical application of dendrobine.

The Biological Parallels Between Atherosclerosis and Cardiac Allograft Vasculopathy: Implications for Solid Organ Chronic Rejection

Atherosclerosis and solid organ chronic rejection are pervasive chronic disease states that account for significant morbidity and mortality in developed countries. Recently, a series of shared molecular pathways have emerged, revealing biological parallels from early stages of development up to the advanced forms of pathology. These shared mechanistic processes are inflammatory in nature, reflecting the importance of inflammation in both disorders. Vascular inflammation triggers endothelial dysfunction and disease initiation through aberrant vasomotor control and shared patterns of endothelial activation. Endothelial dysfunction leads to the recruitment of immune cells and the perpetuation of the inflammatory response. This drives lesion formation through the release of key cytokines such as IFN-y, TNF-alpha, and IL-2. Continued interplay between the adaptive and innate immune response (represented by T lymphocytes and macrophages, respectively) promotes lesion instability and thrombotic complications; hallmarks of advanced disease in both atherosclerosis and solid organ chronic rejection. The aim of this study is to identify areas of overlap between atherosclerosis and chronic rejection. We then discuss new approaches to improve current understanding of the pathophysiology of both disorders, and eventually design novel therapeutics.

The Role of JAK/STAT Signaling Pathway and Its Downstream Influencing Factors in the Treatment of Atherosclerosis

Atherosclerosis is now widely considered to be a chronic inflammatory disease, with increasing evidence suggesting that lipid alone is not the main factor contributing to its development. Rather, atherosclerotic plaques contain a significant amount of inflammatory cells, characterized by the accumulation of monocytes and lymphocytes on the vessel wall. This suggests that inflammation may play a crucial role in the occurrence and progression of atherosclerosis. As research deepens, other pathological factors have also been found to influence the development of the disease. The Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway is a recently discovered target of inflammation that has gained attention in recent years. Numerous studies have provided evidence for the causal role of this pathway in atherosclerosis, and its downstream signaling factors play a significant role in this process. This brief review aims to explore the crucial role of the JAK/STAT pathway and its representative downstream signaling factors in the development of atherosclerosis. It provides a new theoretical basis for clinically affecting the development of atherosclerosis by interfering with the JAK/STAT signaling pathway.

Molecular targets and mechanisms of Guanxinning tablet in treating atherosclerosis: Network pharmacology and molecular docking analysis

BACKGROUND

Guanxinning tablet (GXNT), a Chinese patent medicine, is composed of salvia miltiorrhiza bunge and ligusticum striatum DC, which may play the role of endothelial protection through many pathways. We aimed to explore the molecular mechanisms of GXNT against atherosclerosis (AS) through network pharmacology and molecular docking verification.

METHODS

The active ingredients and their potential targets of GXNT were obtained in traditional Chinese medicine systems pharmacology database and analysis platform and bioinformatics analysis tool for molecular mechanism of traditional Chinese medicine databases. DrugBank, TTD, DisGeNET, OMIM, and GeneCards databases were used to screen the targets of AS. The intersection targets gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis were performed in DAVID database. GXNT-AS protein-protein interaction network, ingredient-target network and herb-target-pathway network were constructed by Cytoscape. Finally, we used AutoDock for molecular docking.

RESULTS

We screened 65 active ingredients of GXNT and 70 GXNT-AS intersection targets. The key targets of protein-protein interaction network were AKT1, JUN, STAT3, TNF, TP53, IL6, EGFR, MAPK14, RELA, and CASP3. The Kyoto encyclopedia of genes and genomes pathway enrichment analysis showed that pathways in cancer, lipid and atherosclerosis, and PI3K-Akt signaling pathway were the main pathways. The ingredient-target network showed that the key ingredients were luteolin, tanshinone IIA, myricanone, dihydrotanshinlactone, dan-shexinkum d, 2-isopropyl-8-methylphenanthrene-3,4-dione, miltionone I, deoxyneocryptotanshinone, Isotanshinone II and 4-methylenemiltirone. The results of molecular docking showed that tanshinone IIA, dihydrotanshinlactone, dan-shexinkum d, 2-isopropyl-8-methylphenanthrene-3,4-dione, miltionone I, deoxyneocryptotanshinone, Isotanshinone II and 4-methylenemiltirone all had good binding interactions with AKT1, EGFR and MAPK14.

CONCLUSION

The results of network pharmacology and molecular docking showed that the multiple ingredients within GXNT may confer protective effects on the vascular endothelium against AS through multitarget and multichannel mechanisms. AKT1, EGFR and MAPK14 were the core potential targets of GXNT against AS.

Major adverse cardiovascular events in patients with atopic dermatitis treated with oral Janus kinase inhibitors: a systematic review and meta-analysis

BACKGROUND

On the basis of safety data for patients with inflammatory rheumatism or inflammatory bowel disease, treatment with Janus kinase (JAK) inhibitors (JAKi) has been linked to the occurrence of major adverse cardiovascular events (MACE). However, these inflammatory diseases are proatherogenic; in contrast, patients with atopic dermatitis (AD) do not usually have a high cardiovascular (CV) comorbidity burden.

OBJECTIVES

To perform a systematic review and meta-analysis of MACE in patients with AD treated with JAKi.

METHODS

We systematically searched PubMed, Embase, Cochrane Library and Google Scholar from their inception to 2 September 2022. Cohort studies, randomized controlled trials and pooled safety analyses providing CV safety data on patients taking JAKi for AD were selected. We included patients aged ≥ 12 years. We built a 'controlled-period' cohort (n = 9309; 6000 exposed to JAKi and 3309 exposed to comparators) and an 'all-JAKi' cohort (n = 9118 patients exposed to a JAKi in any of the included studies). The primary outcome was a composite of acute coronary syndrome (ACS), ischaemic stroke and CV death. The broader secondary MACE outcome encompassed ACS, stroke (whether ischaemic or haemorrhagic), transient ischaemic attack and CV death. The frequency of primary and secondary MACE was assessed in both cohorts. A fixed-effects meta-analysis using the Peto method was used to calculate the odds ratio (OR) for MACE in the 'controlled-period' cohort. Evaluation of the risk of bias was done using the Cochrane risk-of-bias tool (version 2). Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

Eight per cent of the records identified initially met the selection criteria, corresponding to 23 records included in the 'all-JAKi' cohort. Patients had been exposed to baricitinib, upadacitinib, abrocitinib, ivarmacitinib, placebo or dupilumab. Four primary events (three with JAKi and one with placebo) and five secondary events (four with JAKi and one with placebo) occurred among 9309 patients in the 'controlled-period' cohort (MACE frequency 0.04% and 0.05%, respectively). Eight primary events and 13 secondary events occurred among 9118 patients in the 'all-JAKi' cohort (MACE frequency 0.08% and 0.14%, respectively). The OR for primary MACE in patients with AD treated with JAKi vs. placebo or dupilumab was 1.35 (95% confidence interval 0.15-12.21; I2 = 12%, very low certainty of evidence).

CONCLUSIONS

Our review highlights rare cases of MACE among JAKi users for AD. JAKi may have little-to-no effect on the occurrence of MACE in patients with AD vs. comparators, but the evidence is uncertain. Real-life long-term population-level safety studies are needed.

The effects of melatonin against atherosclerosis-induced endothelial dysfunction and inflammation in hypercholesterolemic rats

The aim of this study was to investigate the effects of melatonin on the serum asymmetric dimethylarginine (ADMA) levels and the expressions of vaspin, visfatin, dimethylarginine dimethylaminohydrolase (DDAH), and signal transducer and activator of transcription-3 (STAT-3) for evaluation of endothelial function and inflammation in the hypercholesterolemic rats. Rats were divided into 5 groups: (1) control, (2) hypercholesterolaemia, (3) melatonin administrated concurrently with cholesterol diet, (4) melatonin administrated only last 2 weeks and fed with cholesterol diet, (5) atorvastatin administered only last 2 weeks fed with cholesterol diet. Although an increase was observed in the expressions of visfatin and STAT-3 and the serum ADMA levels, the vaspin and DDAH protein expressions were found to decrease with hypercholesterolemic diets. Melatonin was determined to restore all the parameters to the normal levels. In conclusion, melatonin may have protective and therapeutic effects on hypercholesterolaemia by regulating vaspin, STAT-3, DDAH, and ADMA signalling pathways and create similar effects with atorvastatin.

Transcription factors: key regulatory targets of vascular smooth muscle cell in atherosclerosis

Atherosclerosis (AS), leading to gradual occlusion of the arterial lumen, refers to the accumulation of lipids and inflammatory debris in the arterial wall. Despite therapeutic advances over past decades including intervention or surgery, atherosclerosis is still the most common cause of cardiovascular diseases and the main mechanism of death and disability worldwide. Vascular smooth muscle cells (VSMCs) play an imperative role in the occurrence of atherosclerosis and throughout the whole stages. In the past, there was a lack of comprehensive understanding of VSMCs, but the development of identification technology, including in vivo single-cell sequencing technology and lineage tracing with the CreERT2-loxP system, suggests that VSMCs have remarkable plasticity and reevaluates well-established concepts about the contribution of VSMCs. Transcription factors, a kind of protein molecule that specifically recognizes and binds DNA upstream promoter regions or distal enhancer DNA elements, play a key role in the transcription initiation of the coding genes and are necessary for RNA polymerase to bind gene promoters. In this review, we highlight that, except for environmental factors, VSMC genes are transcriptionally regulated through complex interactions of multiple conserved cis-regulatory elements and transcription factors. In addition, through a series of transcription-related regulatory processes, VSMCs could undergo phenotypic transformation, proliferation, migration, calcification and apoptosis. Finally, enhancing or inhibiting transcription factors can regulate the development of atherosclerotic lesions, and the downstream molecular mechanism of transcriptional regulation has also been widely studied.

The forgotten key players in rheumatoid arthritis: IL-8 and IL-17 - Unmet needs and therapeutic perspectives

Despite the relevant advances in our understanding of the pathogenetic mechanisms regulating inflammation in rheumatoid arthritis (RA) and the development of effective therapeutics, to date, there is still a proportion of patients with RA who do not respond to treatment and end up progressing toward the development of joint damage, extra-articular complications, and disability. This is mainly due to the inter-individual heterogeneity of the molecular and cellular taxonomy of the synovial membrane, which represents the target tissue of RA inflammation. Tumor necrosis factor alpha (TNFα) and interleukin-6 (IL-6) are crucial key players in RA pathogenesis fueling the inflammatory cascade, as supported by experimental evidence derived from in vivo animal models and the effectiveness of biologic-Disease Modifying Anti-Rheumatic Drugs (b-DMARDs) in patients with RA. However, additional inflammatory soluble mediators such as IL-8 and IL-17 exert their pathogenetic actions promoting the detrimental activation of immune and stromal cells in RA synovial membrane, tendons, and extra-articular sites, as well as blood vessels and lungs, causing extra-articular complications, which might be excluded by the action of anti-TNFα and anti-IL6R targeted therapies. In this narrative review, we will discuss the role of IL-8 and IL-17 in promoting inflammation in multiple biological compartments (i.e., synovial membrane, blood vessels, and lung, respectively) in animal models of arthritis and patients with RA and how their selective targeting could improve the management of treatment resistance in patients.

β-Caryophyllene Counteracts Chemoresistance Induced by Cigarette Smoke in Triple-Negative Breast Cancer MDA-MB-468 Cells

Exposure to cigarette smoke (CS) has been associated with an increased risk of fatal breast cancers and recurrence, along with chemoresistance and chemotherapy impairment. This strengthens the interest in chemopreventive agents to be exploited both in healthy and oncological subjects to prevent or repair CS damage. In the present study, we evaluated the chemopreventive properties of the natural sesquiterpene β-caryophyllene towards the damage induced by cigarette smoke condensate (CSC) in triple negative breast cancer MDA-MB-468 cells. Particularly, we assessed the ability of the sesquiterpene to interfere with the mechanisms exploited by CSC to promote cell survival and chemoresistance, including genomic instability, cell cycle progress, autophagy/apoptosis, cell migration and related pathways. β-Caryophyllene was found to be able to increase the CSC-induced death of MDA-MB-468 cells, likely triggering oxidative stress, cell cycle arrest and apoptosis; moreover, it hindered cell recovery, autophagy activation and cell migration; at last, a marked inhibition of the signal transducer and activator of transcription 3 (STAT3) activation was highlighted: this could represent a key mechanism of the chemoprevention by β-caryophyllene. Although further studies are required to confirm the in vivo efficacy of β-caryophyllene, the present results suggest a novel strategy to reduce the harmful effect of smoke in cancer patients and to improve the survival expectations in breast cancer women.

Proteomimetics of Natural Regulators of JAK-STAT Pathway: Novel Therapeutic Perspectives

The JAK-STAT pathway is a crucial cellular signaling cascade, including an intricate network of Protein-protein interactions (PPIs) responsible for its regulation. It mediates the activities of several cytokines, interferons, and growth factors and transduces extracellular signals into transcriptional programs to regulate cell growth and differentiation. It is essential for the development and function of both innate and adaptive immunities, and its aberrant deregulation was highlighted in neuroinflammatory diseases and in crucial mechanisms for tumor cell recognition and tumor-induced immune escape. For its involvement in a multitude of biological processes, it can be considered a valuable target for the development of drugs even if a specific focus on possible side effects associated with its inhibition is required. Herein, we review the possibilities to target JAK-STAT by focusing on its natural inhibitors as the suppressor of cytokine signaling (SOCS) proteins. This protein family is a crucial checkpoint inhibitor in immune homeostasis and a valuable target in immunotherapeutic approaches to cancer and immune deficiency disorders.

FABP4 activates the JAK2/STAT2 pathway via Rap1a in the homocysteine-induced macrophage inflammatory response in ApoE-/- mice atherosclerosis

Atherosclerosis is a chronic inflammatory vascular disease, and inflammation plays a critical role in its formation and progression. Elevated serum homocysteine (Hcy) is an independent risk factor for atherosclerosis. Previous studies have shown that fatty acid binding protein 4 (FABP4) plays an important role in macrophage inflammation and lipid metabolism in atherosclerosis induced by Hcy. However, the underlying molecular mechanism of FABP4 in Hcy-induced macrophage inflammation remains unknown. In this study, we found that FABP4 activated the Janus kinase 2/signal transducer and activator of transcription 2 (JAK2/STAT2) pathway in macrophage inflammation induced by Hcy. Of note, we further observed that ras-related protein Rap-1a (Rap1a) induced the Tyr416 phosphorylation and membrane translocation of non-receptor tyrosine kinase (c-Src) to activate the JAK2/STAT2 pathway. In addition, the suppressor of cytokine signaling 1 (SOCS1)-a transcriptional target of signal transducer and activator of transcription (STATs) inhibited the JAK2/STAT2 pathway and Rap1a expression via a negative feedback loop. In summary, these results demonstrated that FABP4 promotes c-Src phosphorylation and membrane translocation via Rap1a to activate the JAK2/STAT2 pathway, contributing to Hcy-accelerated macrophage inflammation in ApoE-/- mice.

Vascular Inflammation in Cardiovascular Disease: Is Immune System Protective or Bystander?

Cardiovascular disease (CVD) is one of the leading causes of death worldwide. Chronic atherosclerosis induced vascular inflammation and perturbation of lipid metabolism is believed to be a major cause of CVD. Interplay of innate and adaptive Immune system has been interwined with various risk factors associated with the initiation and progression of atherosclerosis in CVD. A large body of evidence indicates a correlation between immunity and atherosclerosis. Retention of plasma lipoproteins in arterial subendothelial wall triggers the T helper type 1 (Th1) cells and monocyte-derived macrophages to form atherosclerotic plaques. In the present review, we will discuss the pathogenesis of CVD in relation to atherosclerosis with a particular focus on pro-atherogenic role of immune cells. Recent findings have also suggested anti-atherogenic roles of different B cell subsets. Therapeutic approaches to target atherosclerosis risk factors have reduced the mortality, but a need exists for the novel therapies to treat arterial vascular inflammation. These insights into the immune pathogenesis of atherosclerosis can lead to new targeted therapeutics to abate cardiovascular mortality and morbidity.

Exploring the regulatory roles of circular RNAs in the pathogenesis of atherosclerosis

Circular RNAs (circRNAs) are a class of noncoding RNAs with a covalently closed loop structure. Recent evidence has shown that circRNAs can regulate gene transcription, alternative splicing, microRNA (miRNA) "molecular sponges", RNA-binding proteins and protein translation. Atherosclerosis is one of the leading causes of death worldwide, and more studies have indicated that circRNAs are related to atherosclerosis pathogenesis, including vascular endothelial cells, vascular smooth muscle cells, inflammation and lipid metabolism. In this review, we systematically summarize the biogenesis, characteristics and functions of circRNAs with a focus on their roles in the pathogenesis of atherosclerosis.

Balasubramide derivative 3C attenuates atherosclerosis in apolipoprotein E-deficient mice: role of AMPK-STAT1-STING signaling pathway

We previously reported the neuroprotective effects of (+)-balasubramide derived compound 3C, but its action on atherosclerosis in vivo remains unknown. The study was designed to investigate the potential effects of 3C on atherogenesis and explore the possible underlying mechanisms. 3C ameliorated high-fat diet-induced body weight gain, hyperlipidemia, and atherosclerotic plaque burden in apolipoprotein E-deficient (ApoE^-/-) mice after 10 weeks of treatment. 3C suppressed the expression of genes involved in triglyceride synthesis in liver. 3C prevented aortic inflammation as evidenced by reduction of adhesive molecule levels and macrophage infiltration. Mechanistic studies revealed that activation of AMP-activated protein kinase (AMPK) is central to the athero-protective effects of 3C. Increased AMPK activity by 3C resulted in suppressing interferon-γ (IFN-γ) induced activation of signal transducer and activator of transcription-1 (STAT1) and stimulator of interferon genes (STING) signaling pathways and downstream pro-inflammatory markers. Moreover, 3C inhibited ox-LDL triggered lipid accumulation and IFN-γ induced phenotypic switch toward M1 macrophage in RAW 264.7 cells. Our present data suggest that 3C prevents atherosclerosis via pleiotropic effects, including amelioration of lipid profiles, vascular inflammation and macrophage pro-inflammatory phenotype. 3C has the potential to be developed as a promising drug for atherosclerosis and related cardiovascular disease.

Elevated retinol binding protein 4 levels are associated with atherosclerosis in diabetic rats via JAK2/STAT3 signaling pathway

BACKGROUND

Atherosclerosis is a major cause of mortality worldwide and is driven by multiple risk factors, including diabetes, which results in an increased atherosclerotic burden, but the precise mechanisms for the occurrence and development of diabetic atherosclerosis have not been fully elucidated.

AIM

To summarize the potential role of retinol binding protein 4 (RBP4) in the pathogenesis of diabetic atherosclerosis, particularly in relation to the RBP4-Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway.

METHODS

Male Wistar rats were randomly divided into three groups, including a control group (NC group), diabetic rat group (DM group), and diabetic atherosclerotic rat group (DA group). The contents of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), triglycerides (TG), low-density lipoprotein cholesterol (LDL-c), fasting insulin (FINS), fasting plasma glucose, and hemoglobin A1c (HbA1c) were measured. Moreover, the adipose and serum levels of RBP4, along with the expression levels of JAK2, phosphorylated JAK2 (p-JAK2), STAT3, phosphorylated STAT3 (p-STAT3), B-cell lymphoma-2 (Bcl-2), and Cyclin D1 in aortic tissues were also measured. Besides, homeostasis model assessment of insulin resistance (HOMA-IR) and atherogenic indexes (AI) were calculated.

RESULTS

Compared with the NC and DM groups, the levels LDL-c, TG, TC, FINS, HOMA-IR, RBP4, and AI were upregulated, whereas that of HDL-c was downregulated in the DA group (P < 0.05); the mRNA levels of JAK2, STAT3, Cyclin D1, and Bcl-2 in the DA group were significantly increased compared with the NC group and the DM group; P-JAK2, p-JAK2/JAK2 ratio, p-STAT3, p-STAT3/STAT3 ratio, Cyclin D1, and Bcl-2 at protein levels were significantly upregulated in the DA group compared with the NC group and DM group. In addition, as shown by Pearson analysis, serum RBP4 had a positive correlation with TG, TC, LDL-c, FINS, HbA1C, p-JAK2, p-STAT3, Bcl-2, Cyclin D1, AI, and HOMA-IR but a negative correlation with HDL-c. In addition, multivariable logistic regression analysis showed that serum RBP4, p-JAK2, p-STAT3, and LDL-c were predictors of the presence of diabetic atherosclerosis.

CONCLUSION

RBP4 could be involved in the initiation or progression of diabetic atherosclerosis by regulating the JAK2/STAT3 signaling pathway.

Cytokine Storm and Mucus Hypersecretion in COVID-19: Review of Mechanisms

Mucus is an integral part of the respiratory physiology. It protects the respiratory tract by acting as a physical barrier against inhaled particles and microbes. Excessive inflammation in conditions such as COVID-19 can result in over-production of mucus which obstructs the airway. Build-up of mucus can also contribute to recurrent airway infection, causing further obstruction. This article summarizes the current understanding and knowledge of respiratory mucus production and proposes the role of cytokine storm in inducing sudden mucus hypersecretion in COVID-19. Based on these cascades, the active constituents that inhibit or activate several potential targets are outlined for further research. These may be explored for the discovery and design of drugs to combat cytokine storm and its ensuing complications.

Inhibition of JAK2 Suppresses Myelopoiesis and Atherosclerosis in Apoe-/- Mice

OBJECTIVE

Increased myelopoiesis has been linked to risk of atherosclerotic cardiovascular disease (ACD). Excessive myelopoiesis can be driven by dyslipidemia and cholesterol accumulation in hematopoietic stem and progenitor cells (HSPC) and may involve increased signaling via Janus kinase 2 (JAK2). Constitutively activating JAK2 mutants drive biased myelopoiesis and promote development of myeloproliferative neoplasms (MPN) or clonal hematopoiesis, conditions associated with increased risk of ACD. JAK2 inhibitors have been developed as a therapy for MPNs. The potential for JAK2 inhibitors to protect against atherosclerosis has not been tested. We therefore assessed the impact of JAK2 inhibition on atherogenesis.

METHODS

A selective JAK2 inhibitor TG101348 (fedratinib) or vehicle was given to high-fat high-cholesterol Western diet (WD)-fed wild-type (WT) or Apoe^-/- mice. Hematopoietic cell profiles, cell proliferation, and atherosclerosis in WT or Apoe^-/- mice were assessed.

RESULTS

TG101348 selectively reversed neutrophilia, monocytosis, HSPC, and granulocyte-macrophage progenitor (GMP) expansion in Apoe^-/- mice with decreased cellular phosphorylated STAT5 and ERK1/2 and reduced cell cycling and BrdU incorporation in HSPCs, indicating inhibition of JAK/STAT signaling and cell proliferation. Ten-week WD feeding allowed the development of marked aortic atherosclerosis in Apoe^-/- mice which was substantially reduced by TG101348.

CONCLUSIONS

Selective JAK2 inhibition reduces atherogenesis by suppressing excessive myelopoiesis in hypercholesterolemic Apoe^-/- mice. These findings suggest selective JAK2 inhibition as a potential therapeutic approach to decrease ACD risk in patients with increased myelopoiesis and leukocytosis.

Antioxidant Effects of PS5, a Peptidomimetic of Suppressor of Cytokine Signaling 1, in Experimental Atherosclerosis

The chronic activation of the Janus kinase/signal transducer and activator of the transcription (JAK/STAT) pathway is linked to oxidative stress, inflammation and cell proliferation. Suppressors of cytokine signaling (SOCS) proteins negatively regulate the JAK/STAT, and SOCS1 possesses a small kinase inhibitory region (KIR) involved in the inhibition of JAK kinases. Several studies showed that KIR-SOCS1 mimetics can be considered valuable therapeutics in several disorders (e.g., diabetes, neurological disorders and atherosclerosis). Herein, we investigated the antioxidant and atheroprotective effects of PS5, a peptidomimetic of KIR-SOCS1, both in vitro (vascular smooth muscle cells and macrophages) and in vivo (atherosclerosis mouse model) by analyzing gene expression, intracellular O₂^•− production and atheroma plaque progression and composition. PS5 was revealed to be able to attenuate NADPH oxidase (NOX1 and NOX4) and pro-inflammatory gene expression, to upregulate antioxidant genes and to reduce atheroma plaque size, lipid content and monocyte/macrophage accumulation. These findings confirm that KIR-SOCS1-based drugs could be excellent antioxidant agents to contrast atherosclerosis.

A chalcone derivative, 1m-6, exhibits atheroprotective effects by increasing cholesterol efflux and reducing inflammation-induced endothelial dysfunction

BACKGROUND AND PURPOSE

Atherosclerosis, resulting from lipid dysregulation and vascular inflammation, causes atherosclerotic cardiovascular disease (ASCVD), which contributes to morbidity and mortality worldwide. Chalcone and its derivatives possess beneficial properties, including anti-inflammatory, antioxidant and antitumour activity with unknown cardioprotective effects. We aimed to develop an effective chalcone derivative with antiatherogenic potential.

EXPERIMENTAL APPROACH

Human THP-1 cells and HUVECs were used as in vitro models. Western blots and real-time PCRs were performed to quantify protein, mRNA and miRNA expressions. The cholesterol efflux capacity was assayed by ³ H labelling of cholesterol. LDL receptor knockout (Ldlr^-/- ) mice fed a high-fat diet were used as an in vivo atherogenesis model. Haematoxylin and eosin and oil red O staining were used to analyse plaque formation.

KEY RESULTS

Using ATP-binding cassette transporter A1 (ABCA1) expression we identified the chalcone derivative, 1m-6, which enhances ABCA1 expression and promotes cholesterol efflux in THP-1 macrophages. Moreover, 1m-6 stabilizes ABCA1 mRNA and suppresses the expression of potential ABCA1-regulating miRNAs through nuclear factor erythroid 2-related factor 2 (Nrf2)/haem oxygenase-1 (HO-1) signalling. Additionally, 1m-6 significantly inhibits TNF-α-induced expression of adhesion molecules, vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1), plus production of proinflammatory cytokines via inhibition of JAK/STAT3 activation and the modulation of Nrf2/HO-1 signalling in HUVECs. In atherosclerosis-prone mice, 1m-6 significantly reduces lipid accumulation and atherosclerotic plaque formation.

CONCLUSION AND IMPLICATIONS

Our study demonstrates that 1m-6 produces promising atheroprotective effects by enhancing cholesterol efflux and suppressing inflammation-induced endothelial dysfunction, which opens a new avenue for treating ASCVD.

LINKED ARTICLES

This article is part of a themed issue on Risk factors, comorbidities, and comedications in cardioprotection. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.23/issuetoc.

WWP2 regulates SIRT1-STAT3 acetylation and phosphorylation involved in hypertensive angiopathy

WWP2 is a HECT‐type E3 ubiquitin ligase that regulates various physiological and pathological activities by binding to different substrates, but its function and regulatory mechanism in vascular smooth muscle cells (VSMCs) are still unknown. Here, we clarified the role of WWP2 in the regulation of SIRT1‐STAT3 and the impact of this regulatory process in VSMCs. We demonstrated that WWP2 expression was significantly increased in angiotensin II‐induced VSMCs model. Knockdown of WWP2 significantly inhibited angiotensin II‐induced VSMCs proliferation, migration and phenotypic transformation, whereas overexpression of WWP2 had opposite effects. In vivo experiments showed that vascular smooth muscle‐specific WWP2 knockout mice significantly relieved angiotensin II‐induced hypertensive angiopathy. Mechanistically, mass spectrometry and co‐immunoprecipitation assays identified that WWP2 is a novel interacting protein of SIRT1 and STAT3. Moreover, WWP2 formed a complex with SIRT1‐STAT3, inhibiting the interaction between SIRT1 and STAT3, then reducing the inhibitory effect of SIRT1 on STAT3, ensuing promoting STAT3‐K685 acetylation and STAT3‐Y705 phosphorylation in angiotensin II‐induced VSMCs and mice. In conclusion, WWP2 modulates hypertensive angiopathy by regulating SIRT1‐STAT3 and WWP2 suppression in VSMCs can alleviate hypertensive angiopathy vitro and vivo. These findings provide new insights into the treatment of hypertensive vascular diseases.

Downregulation of microRNA‑106a‑5p alleviates ox‑LDL‑mediated endothelial cell injury by targeting STAT3

The apoptosis of endothelial cells (ECs) induced by oxidized low-density lipoprotein (ox-LDL) is an important contributing factor in the pathogenesis of atherosclerosis. It has been reported that microRNA (miR)-106a-5p is overexpressed in atherosclerotic plaques and involved in angiogenesis. However, its role and underlying mechanisms in ox-LDL induced EC apoptosis remain to be fully understood. In the present study the expression of miR-106a-5p in human umbilical vein ECs (HUVECs) stimulated with ox-LDL was investigated using reverse transcription-quantitative PCR analysis. Cell viability and apoptosis were assessed by MTT assay and flow cytometry, respectively. Caspase-3 activity and reactive oxygen species (ROS) levels were determined by commercial kits. The interaction between miR-106a-5p and signal transducer and activator of transcription 3 (STAT3) mRNA was examined by luciferase reporter assay. It was found that ox-LDL treatment significantly increased the levels of miR-106a-5p in a dose-dependent manner in HUVECs. Moreover, these results demonstrated that ox-LDL treatment inhibited cell viability, promoted cell apoptosis, increased caspase-3 activity and ROS levels, whereas inhibition of miR-106a-5p reversed the effects of ox-LDL on HUVECs. In addition, it was shown that STAT3 is a direct target of miR-106a-5p in HUVECs, and silencing of STAT3 impaired the protective effects of miR-106a-5p inhibition on cell apoptosis and oxidative injury induced by ox-LDL. Collectively, these results indicated that miR-106a-5p participated in ox-LDL-stimulated apoptosis and oxidative injury in HUVECs by regulating STAT3. Thus, suggesting that miR-106a-5p/STAT3 may serve as a novel therapeutic target for atherosclerosis in the future.

Inhibition of JAK2/STAT3/SOCS3 signaling attenuates atherosclerosis in rabbit

Background

Previous studies have indicated that the JAK/STAT signaling pathway is involved in modulating arterial adventitia inflammation response. In this study, we designed experiments to further investigate the effect of JAK2/STAT3/SOCS3 signaling in rabbit atherosclerosis process.

Methods

Atherosclerosis was induced in the abdominal arteries of rabbits by balloon injury of the aorta supplemented by the atherogenic diet. Simultaneously, in the process of atherosclerosis, animals underwent either ruxolitinib treatment or not for 12 weeks. At the end of the experimental period, all rabbits were sacrificed. The plaque areas in abdominal artery, the lipid burden of plaque and the calcium burden of plaque were detected by H&E staining, Oil Red O staining and Alizarin Red staining, respectively. In addition, rabbit plasma lipids and inflammatory cytokines were measured by biochemical test kits or ELISA kits. Finally, the expression and phosphorylation levels of JAK2/STAT3/SOCS3 pathway-related proteins were detected by RT-qPCR, western blot and immunohistochemistry assays.

Results

H&E staining and CT scan analysis showed that rabbit atherosclerosis model was constructed successfully. Ruxolitinib, an inhibitor of the Janus kinase 2 (JAK2), substantially reduced the area of atherosclerotic plaques in rabbits treated with high fat diet and balloon injury of the aorta. Moreover, ruxolitinib significantly decreased IL-6, IL-1β, IFN-γ and TNF-α, but increased IL-10 and IL-17 levels in plasma of atherosclerotic rabbits. Additionally, ruxolitinib reduced plasma TC, TG and LDL-C contents and AIP value, while enhanced HDL-C level in atherosclerotic rabbits. Furthermore, we found that JAK2 and STAT3 phosphorylation were up-regulated in rabbits with atherosclerosis when compared with those of the control group, followed by the expression of SOCS3 was also increased due to the activation of JAK2 and STAT3. Interestingly, ruxolitinib could inactivate JAK2 and STAT3 pathway and decrease SOCS3 expression.

Conclusion

Taken together, the inhibition of JAK2/STAT3/SOCS3 signaling pathway may be a novel method for the clinical treatment of artery atherosclerosis.

Dermatophagoides pteronyssinus-induced pro-inflammatory responses mediated via STAT3 and NF-kappaB signaling pathways in human bronchial epithelial cells - Inhibitory effects of Lafoensia pacari and ellagic acid

The house dust mite allergen Dermatophagoides pteronyssinus (Der p) is a major driver of allergic asthma. Studies from our group demonstrated anti-eosinophilic effects of ethanolic extract of Lafoensia pacari stem bark (and ellagic acid, isolated from L. pacari extract), used as traditional medicine in Brazil to naturally treat inflammatory conditions. Here, we extended these results through performing phytochemical analysis of the constituents of L. pacari using liquid chromatography-mass spectrometry and evaluating the anti-inflammatory effects of both L. pacari and ellagic acid in the human BEAS-2B bronchial epithelial cell line stimulated with Der p. Ellagic acid (major constituent), gallic acid, ferulic acid, chlorogenic acid and rosmarinic acid, but not flavonoids (rutin, kaempferol, luteolin and quercetin), were found in the L. pacari. Pro-inflammatory mediators, IL-6, IL-8 and CCL-2 production were increased in BEAS-2B stimulated with Der p (10 μg/mL, 24 h) compared to control. L. pacari (250 μg/mL) and ellagic acid (100 μM) significantly reduced the concentration of these mediators. L. pacari increased the production of the anti-inflammatory cytokine, IL-10. These results were associated with the downregulation of NF-κB and STAT3 pathways. These findings indicate a novel anti-inflammatory action for L. pacari and ellagic acid in the airways allergic inflammatory response.

The interaction between STAT3 and nAChRα1 interferes with nicotine-induced atherosclerosis via Akt/mTOR signaling cascade

During atherosclerosis development, nicotine and its α1 nicotinic acetylcholine receptors (nAChRα1) activate atherogenic inflammation. However, the effect of signal transducer and activator of transcription 3 (STAT3)-related inflammatory pathways in nicotine-induced atherosclerosis has been poorly studied. This study investigated the transcriptional mechanism of STAT3 in nicotine/nAChRα1-induced atherosclerosis. In vivo, ApoE-/- mice were used to establish an atherosclerotic model. Plaque area and composition were assessed by oil red O staining and immunohistochemistry. In vitro, vascular smooth muscle cells and macrophages were used to investigate cell migration, proliferation, inflammation and related signaling pathways by Transwell migration assay, EdU assay, immunofluorescence, western blotting, coimmunoprecipitation and chromatin immunoprecipitation. nAChRα1 knockdown significantly decreases the nicotine-induced upregulation of p-STAT3, p-Akt and p-mTOR in vitro, while nAChRα1 overexpression has the opposite effects. The inhibition of STAT3 attenuated nicotine-induced atherosclerosis, by reducing the proliferation and migration of vascular smooth muscle cells and inflammation in macrophages. Moreover, there is a direct interaction between STAT3 and nAChRα1 that modulates STAT3 nuclear translocation and its binding to the Akt promoter region upon nicotine exposure. Taken together, STAT3 and nAChRα1 blockade attenuates nicotine-induced atherosclerosis by reducing the migration and proliferation of vascular smooth muscle cells and inflammation in macrophages via the Akt/mTOR pathway.

Targeting Inflammation by Flavonoids: Novel Therapeutic Strategy for Metabolic Disorders

A balanced metabolic profile is essential for normal human physiological activities. Disproportions in nutrition give rise to imbalances in metabolism that are associated with aberrant immune function and an elevated risk for inflammatory-associated disorders. Inflammation is a complex process, and numerous mediators affect inflammation-mediated disorders. The available clinical modalities do not effectively address the underlying diseases but rather relieve the symptoms. Therefore, novel targeted agents have the potential to normalize the metabolic system and, thus, provide meaningful therapy to the underlying disorder. In this connection, polyphenols, the well-known and extensively studied phytochemical moieties, were evaluated for their effective role in the restoration of metabolism via various mechanistic signaling pathways. The various flavonoids that we observed in this comprehensive review interfere with the metabolic events that induce inflammation. The mechanisms via which the polyphenols, in particular flavonoids, act provide a promising treatment option for inflammatory disorders. However, detailed clinical studies of such molecules are required to decide their clinical fate.

Organic dust induces inflammatory gene expression in lung epithelial cells via ROS-dependent STAT-3 activation

Exposure to dust in agricultural and animal environments, known as organic dust, is associated with the development of respiratory symptoms and respiratory diseases. Inflammation is a key feature of lung pathologies associated with organic dust exposure, and exposure to organic dust induces the expression of several immune and inflammatory mediators. However, information on transcription factors and cellular and molecular mechanisms controlling the production of immune and inflammatory mediators induced by organic dust is limited. In this study, we have identified STAT-3 as an important transcription factor controlling the induction of expression of immune and inflammatory mediators by poultry dust extracts in airway epithelial cells and in mouse lungs and delineated the cellular pathway for STAT-3 activation. Poultry dust extract activated STAT-3 phosphorylation in Beas2B and normal human bronchial epithelial cells and in mouse lungs. Chemical inhibition and siRNA knockdown of STAT-3 suppressed induction of immune and inflammatory mediator expression. Antioxidants suppressed the increase of STAT-3 phosphorylation induced by poultry dust extract indicating that oxidative stress [elevated reactive oxygen species (ROS) levels] is important for the activation. Chemical inhibition and siRNA knockdown experiments demonstrated that STAT-3 activation is dependent on the activation of nonreceptor tyrosine-protein kinase 2 (TYK2) and epidermal growth factor receptor (EGFR) tyrosine kinases. Our studies show that poultry dust extract controls the induction of immune and inflammatory mediator expression via a cellular pathway involving oxidative stress-mediated STAT-3 activation by TYK2 and EGFR tyrosine kinases.

Curcumin ameliorates atherosclerosis through upregulation of miR-126

The potential usage of curcumin in diverse human diseases has been widely studied, including arteriosclerosis (AS). This study focused on investigating the relationship between curcumin and AS-associated microRNA, which may provide a better understanding of curcumin in a different mechanism. Human microvascular endothelial HMEC-1 cells were treated by curcumin alone or oxidized low-density lipoprotein (ox-LDL) plus curcumin, after which the following parameters were analyzed: cell viability, migration, and the expression of AS-associated factors. The regulatory effects of curcumin on miR-126 and signaling pathways involved in AS were then studied. Further, an animal model of AS was stimulated by feeding rabbits with 1% cholesterol diet. The effects of curcumin on the animal model were explored. We found that curcumin treatment significantly reduced HMEC-1 cells viability, migration, and the protein levels of MMP-2, MMP-9, and vascular endothelial growth factor (VEGF) in the presence or absence of ox-LDL. Meanwhile, the expression of VEGFR1 and VEGFR2 was repressed by curcumin. miR-126 was upregulated by curcumin. The abovementioned effects of curcumin on HMEC-1 cells were all attenuated when miR-126 was silenced. And also, VEGF was a target gene of miR-126, and curcumin could inhibit the activation of PI3K/AKT JAK2/STAT5 signaling pathways via miR-126. The effects of curcumin and its regulation on miR-126 and VEGF were confirmed in the animal model of AS. To sum up, curcumin exerted potent anti-AS property possibly via upregulating miR-126 and thereby inhibiting PI3K/AKT and JAK2/STAT5 signaling pathways.

CircRNA‑0044073 is upregulated in atherosclerosis and increases the proliferation and invasion of cells by targeting miR‑107

Circular RNAs (circRNAs) are endogenous non‑coding RNAs implicated in atherosclerosis. The aim of the present study was to explore the function of circRNA‑0044073 in atherosclerosis. Reverse transcription quantitative polymerase chain reaction assays were used to measure the expression levels of circRNA‑0044073, microRNA (miRNA/miR)‑107, janus kinase 1 (JAK1), signal transducer and activator of transcription 3 (STAT3), B‑cell lymphoma 2 (Bcl‑2) and v‑myc avian myelocytomatosis viral oncogene homolog (c‑myc) in in blood cells from patients with atherosclerosis. RNA pull‑down and luciferase reporter assays were then used to determine the association between circRNA and miR expression, and miR and gene expression, respectively. Matrigel invasion assay and flow cytometry were used to analyze cell invasion and cell cycle. Western blot analysis and ELISA were used to evaluate the expression levels of proteins. It was identified that the expression of circRNA‑0044073 was upregulated and the expression of miR‑107 was downregulated in atherosclerotic blood cells. Overexpression of circRNA‑0044073 promoted the proliferation of human vascular smooth muscle cells (HUVSMCs) and human vascular endothelial cells (HUVECs), while overexpression of miR‑107 inhibited their proliferation. In addition, circRNA‑0044073 suppressed the levels of miR‑107 via a sponge mechanism. Lipopolysaccharide (LPS) affected the proliferation of HUVSMCs and HUVECs, and also resulted in changes in circRNA‑0044073 expression levels. CircRNA‑0044073 promoted the proliferation and invasion of HUVSMCs and HUVECs in spite of the opposite effect observed with LPS treatment. The JAK/STAT signaling pathway was activated in patients with atherosclerosis. CircRNA‑0044073 favored the activation of the JAK/STAT signaling pathway and inflammation in HUVSMCs and HUVECs. These data indicate that circRNA‑0044073 is upregulated in atherosclerosis and promotes the proliferation and invasion of cells by targeting miR‑107 and activating the JAK/STAT signaling pathway, potentially offering a target for novel treatment strategies against atherosclerosis.

Regulation of platelet-activating factor-induced interleukin-8 expression by protein tyrosine phosphatase 1B

Background

Platelet-activating factor (PAF) is a potent lipid mediator whose involvement in the onset and progression of atherosclerosis is mediated by, among others, the modulation of cytokine expression patterns. The presence of multiple potential protein-tyrosine phosphatase (PTP) 1B substrates in PAF receptor signaling pathways brought us to investigate its involvement in PAF-induced cytokine expression in monocyte-derived dendritic cells (Mo-DCs) and to study the pathways involved in this modulation.

Methods

We used in-vitro-matured human dendritic cells and the HEK-293 cell line in our studies. PTP1B inhibition was though siRNAs and a selective inhibitor. Cytokine expression was studied with RT-PCR, luciferase assays and ELISA. Phosphorylation status of kinases and transcription factors was studied with western blotting.

Results

Here, we report that PTP1B was involved in the modulation of cytokine expression in PAF-stimulated Mo-DCs. A study of the down-regulation of PAF-induced IL-8 expression, by PTP1B, showed modulation of PAF-induced transactivation of the IL-8 promoter which was dependent on the presence of the C/EBPß -binding site. Results also suggested that PTP1B decreased PAF-induced IL-8 production by a glycogen synthase kinase (GSK)-3-dependent pathway via activation of the Src family kinases (SFK). These kinases activated an unidentified pathway at early stimulation times and the PI3K/Akt signaling pathway in a later phase. This change in GSK-3 activity decreased the C/EBPß phosphorylation levels of the threonine 235, a residue whose phosphorylation is known to increase C/EBPß transactivation potential, and consequently modified IL-8 expression.

Conclusion

The negative regulation of GSK-3 activity by PTP1B and the consequent decrease in phosphorylation of the C/EBPß transactivation domain could be an important negative feedback loop by which cells control their cytokine production after PAF stimulation.

Electronic supplementary material

The online version of this article (10.1186/s12964-019-0334-6) contains supplementary material, which is available to authorized users.

Bradykinin B1 receptor contributes to interleukin-8 production and glioblastoma migration through interaction of STAT3 and SP-1

Glioblastoma (GBM), the most aggressive brain tumor, has a poor prognosis due to the ease of migration to surrounding healthy brain tissue. Recent studies have shown that bradykinin receptors are involved in the progression of various cancers. However, the molecular mechanism and pathological role of bradykinin receptors remains unclear. We observed the expressions of two major bradykinin receptors, B1R and B2R, in two different human GBM cell lines, U87 and GBM8901. Cytokine array analysis showed that bradykinin increases the production of interleukin (IL)-8 in GBM via B1R. Higher B1R levels correlate with IL-8 expression in U87 and GBM8901. We observed increased levels of phosphorylated STAT3 and SP-1 in the nucleus as well. Using chromatin immunoprecipitation assay, we found that STAT3 and SP-1 mediate IL-8 expression, which gets abrogated by the inhibition of FAK and STAT3. We further demonstrated that IL-8 expression and cell migration are also regulated by the SP-1. In addition, expression levels of STAT3 and SP-1 positively correlate with clinicopathological grades of gliomas. Interestingly, our results found that inhibition of HDAC increases IL-8 expression. Moreover, stimulation with bradykinin caused increases in acetylated SP-1 and p300 complex formation, which are abrogated by inhibition of FAK and STAT3. Meanwhile, knockdown of SP-1 and p300 decreased the augmentation of bradykinin-induced IL-8 expression. These results indicate that bradykinin-induced IL-8 expression is dependent on B1R which causes phosphorylated STAT3 and acetylated SP-1 to translocate to the nucleus, hence resulting in GBM migration.

NOXA1-dependent NADPH oxidase regulates redox signaling and phenotype of vascular smooth muscle cell during atherogenesis

Increased reactive oxygen species (ROS) production and inflammation are key factors in the pathogenesis of atherosclerosis. We previously reported that NOX activator 1 (NOXA1) is the critical functional homolog of p67phox for NADPH oxidase activation in mouse vascular smooth muscle cells (VSMC). Here we investigated the effects of systemic and SMC-specific deletion of Noxa1 on VSMC phenotype during atherogenesis in mice.

Neointimal hyperplasia following endovascular injury was lower in Noxa1-deficient mice versus the wild-type following endovascular injury. Noxa1 deletion in Apoe^-/- or Ldlr^-/- mice fed a Western diet showed 50% reduction in vascular ROS and 30% reduction in aortic atherosclerotic lesion area and aortic sinus lesion volume (P < 0.01). SMC-specific deletion of Noxa1 in Apoe^-/- mice (Noxa1^SMC-/-/Apoe^-/-) similarly decreased vascular ROS levels and atherosclerotic lesion size. TNFα-induced ROS generation, proliferation and migration were significantly attenuated in Noxa1-deficient versus wild-type VSMC. Immunofluorescence analysis of atherosclerotic lesions showed a significant decrease in cells positive for CD68 and myosin11 (22% versus 9%) and Mac3 and α-actin (17% versus 5%) in the Noxa1^SMC-/-/Apoe^-/- versus Apoe^-/- mice. The expression of transcription factor KLF4, a modulator of VSMC phenotype, and its downstream targets – VCAM1, CCL2, and MMP2 – were significantly reduced in the lesions of Noxa1^SMC-/-/Apoe^-/- versus Apoe^-/- mice as well as in oxidized phospholipids treated Noxa1^SMC-/- versus wild-type VSMC.

Our data support an important role for NOXA1-dependent NADPH oxidase activity in VSMC plasticity during restenosis and atherosclerosis, augmenting VSMC proliferation and migration and KLF4-mediated transition to macrophage-like cells, plaque inflammation, and expansion.

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NOXA1 is a VSMC-specific regulator of NADPH oxidase 1 activity and downstream cell signaling.

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NOX1 NADPH oxidase-dependent ROS generation is required for VSMC proliferation and migration after endovascular injury.

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NOXA1-dependent NOX1 activation of KLF4 in atherosclerotic lesions induces SMC phenotypic switch to macrophage-like cells.

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Atherosclerotic lesion macrophage-like cells promote plaque inflammation, matrix remodeling and increase volume expansion.

Oxidized lipids: not just another brick in the wall 1

Over the past decade, there has been intense investigation in trying to understand the pathological role that oxidized phospholipids play in cardiovascular disease. Phospholipids are targets for oxidation, particularly during conditions of excess free radical generation. Once oxidized, they acquire novel roles uncharacteristic of their precursors. Oxidized phosphatidylcholines have an important role in multiple physiological and pathophysiological conditions including atherosclerosis, neurodegenerative diseases, lung disease, inflammation, and chronic alcohol consumption. Circulating oxidized phosphatidylcholine may also serve as a clinical biomarker. The focus of this review, therefore, will be to summarize existing evidence that oxidized phosphatidylcholine molecules play an important role in cardiovascular pathology.

Luteolin suppresses the JAK/STAT pathway in a cellular model of intestinal inflammation

Current treatment strategies for inflammatory bowel diseases (IBDs) are associated with a lower efficacy and with several side effects that strongly affect the quality of life of IBD patients. Consequently, the development of new therapies, combining efficacy and safety is an important goal in the field of intestinal inflammation. In this context, evidence supports that polyphenols can be promising candidates due to their ability to modulate intracellular inflammatory signalling cascades. Luteolin, a naturally occurring flavonoid, exhibits anti-inflammatory properties in several models of inflammation. However, its action against intestinal inflammation has been poorly explored. Therefore, there is a lack of scientific knowledge about the potential impact of luteolin in the intestinal inflammation, particularly regarding the underlying molecular mechanisms by which luteolin can exert its anti-inflammatory action. We assessed the potential anti-inflammatory effect of luteolin in a cellular model of intestinal inflammation using cytokine-stimulated HT-29 colon epithelial cells, and the underlying key molecular mechanisms were identified. Luteolin significantly inhibited interleukine-8 (IL-8) production, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression and nitric oxide (˙NO) overproduction induced by cytokines, indicating that luteolin negatively modulates key inflammatory signalling cascades underlying intestinal inflammation. Mechanistically, the inhibition of the JAK/STAT pathway was identified as a critical mechanism by which luteolin exerts its intestinal anti-inflammatory action. This study uncovers novel molecular mechanisms by which luteolin may act against intestinal inflammation, which might support the use of luteolin as a future therapeutic strategy in IBD.

The role of lnc-DC long non-coding RNA and SOCS1 in the regulation of STAT3 in coronary artery disease and type 2 diabetes mellitus

AIMS

Coronary artery disease (CAD) can be classified as an inflammatory disease, which affected by type 2 diabetes mellitus (T2DM). Elevated levels of many inflammatory molecules were found in the serum of patients with CAD. STAT3 molecule as a transcription factor plays an important role in the cytokines expression. Here, we examined the expression levels of STAT3 and its important regulatory genes lnc-DC and SOCS1, in patients with CAD and T2DM.

METHODS

Blood samples were obtained from 37 CAD+ and 36 CAD- patients. These patients were enrolled in this study based on angiography findings and categorized based on T2DM status. The expression levels of STAT3, lnc-DC and SOCS1 genes were examined with Real time PCR method.

RESULTS

A significant increase was observed in expression of STAT3 and lnc-DC genes but not SOCS1 in CAD+ versus CAD- patients. These results replicated partially in some groups categorized based on T2DM and CAD status. However, severity of CAD had no effect on expressions of these genes. Moreover, we found some significant correlations between expressions of lnc-DC with SOCS1 and STAT3, which confirmed by in silico analysis.

CONCLUSION

Our results shed further light to the inflammatory aspects of CAD and T2DM with emphasis to JAK/STAT pathway and the regulatory role of long non-coding RNAs in the physiopathology of these diseases.

The ablation of the matricellular protein EMILIN2 causes defective vascularization due to impaired EGFR-dependent IL-8 production affecting tumor growth

EMILIN2 is an extracellular matrix constituent playing an important role in angiogenesis; however, the underlying mechanism is unknown. Here we show that EMILIN2 promotes angiogenesis by directly binding epidermal growth factor receptor (EGFR), which enhances interleukin-8 (IL-8) production. In turn, IL-8 stimulates the proliferation and migration of vascular endothelial cells. Emilin2 null mice were generated and exhibited delayed retinal vascular development, which was rescued by the administration of the IL-8 murine ortholog MIP-2. Next, we assessed tumor growth and tumor-associated angiogenesis in these mice. Tumor cell growth in Emilin2 null mice was impaired as well as the expression of MIP-2. The vascular density of the tumors developed in Emilin2 null mice was prejudiced and vessels perfusion, as well as response to chemotherapy, decreased. Accordingly, human tumors expressing high levels of EMILIN2 were more responsive to chemotherapy. These results point at EMILIN2 as a key microenvironmental cue affecting vessel formation and unveil the possibility to develop new prognostic tools to predict chemotherapy efficacy.

MIAT promotes proliferation and hinders apoptosis by modulating miR-181b/STAT3 axis in ox-LDL-induced atherosclerosis cell models

BACKGROUND

Plenty of lncRNAs and microRNAs have been identified to be critical mediators in the progression of atherosclerosis (AS). Myocardial infarction-associated transcript (MIAT) were aberrantly high expressed and closely associated with the pathogenesis of AS. However, its molecular mechanism has not been well characterized.

METHODS

The expression patterns of MIAT and microRNA-181b (miR-181b) in clinical samples and cells were measured by RT-qPCR assays. Luciferase reporter assay and RIP assays were used to manifest the potential interaction between MIAT, miR-181b and signal transducer and activator of transcription 3 (STAT3). Cell Counting Kit-8 (CCK-8), Propidium Iodide (PI) staining, Terminal dexynucleotidyl transferase(TdT)-mediated dUTP nick end labeling (TUNEL) and western blot assays were carried out to detect cell proliferation, cell cycle distribution, apoptosis, and STAT3 protein level, respectively.

RESULTS

MIAT expression was up-regulated and miR-181b expression was down-regulated in AS patients serum and oxidized low-density lipoprotein (ox-LDL) induced AS cells model. MIAT facilitated cell proliferation, accelerated cell cycle progression and inhibited apoptosis in ox-LDL-induced AS cell lines, while this effect was partly reversed by miR-181b overexpression. Moreover, MIAT enhanced STAT3 expression through sequestering miR-181b as a molecular sponge. Furthermore, MiR-181b hindered cell growth, induced cell cycle arrest and promoted apoptosis by directly targeting STAT3.

CONCLUSION

MIAT performed as an induction factor of AS by regulating miR-181b/STAT3 axis in ox-LDL-induced AS cell lines, offering a new insight into the potential application of MIAT in AS treatment.

Expression of the JAK/STAT Signaling Pathway in Bullous Pemphigoid and Dermatitis Herpetiformis

A family of eleven proteins comprises the Janus kinases (JAK) and signal transducers and activators of transcription (STAT) signaling pathway, which enables transduction of signal from cytokine receptor to the nucleus and activation of transcription of target genes. Irregular functioning of the cascade may contribute to pathogenesis of autoimmune diseases; however, there are no reports concerning autoimmune bullous diseases yet to be published. The aim of this study was to evaluate the expression of proteins constituting the JAK/STAT signaling pathway in skin lesions and perilesional area in dermatitis herpetiformis (DH) and bullous pemphigoid (BP), as well as in the control group. Skin biopsies were collected from 21 DH patients, from 20 BP patients, and from 10 healthy volunteers. The localization and expression of selected STAT and JAK proteins were examined by immunohistochemistry and immunoblotting. We found significantly higher expression of JAK/STAT proteins in skin lesions in patients with BP and DH, in comparison to perilesional skin and the control group, which may be related to proinflammatory cytokine network and induction of inflammatory infiltrate in tissues. Our findings suggest that differences in the JAK and STAT expression may be related to distinct cytokines activating them and mediating neutrophilic and/or eosinophilic infiltrate.

Potential humoral mediators of remote ischemic preconditioning in patients undergoing surgical coronary revascularization

Remote ischemic preconditioning (RIPC) by repeated brief cycles of limb ischemia/reperfusion may reduce myocardial ischemia/reperfusion injury and improve patients‘ prognosis after elective coronary artery bypass graft (CABG) surgery. The signal transducer and activator of transcription (STAT)5 activation in left ventricular myocardium is associated with RIPC´s cardioprotection. Cytokines and growth hormones typically activate STATs and could therefore act as humoral transfer factors of RIPC´s cardioprotection. We here determined arterial plasma concentrations of 25 different cytokines, growth hormones, and other factors which have previously been associated with cardioprotection, before (baseline)/after RIPC or placebo (n = 23/23), respectively, and before/after ischemic cardioplegic arrest in CABG patients. RIPC-induced protection was reflected by a 35% reduction of serum troponin I release. With the exception of interleukin-1α, none of the humoral factors changed in their concentrations after RIPC or placebo, respectively. Interleukin-1α, when normalized to baseline, increased after RIPC (280 ± 56%) but not with placebo (97 ± 15%). The interleukin-1α concentration remained increased until after ischemic cardioplegic arrest and was also higher than with placebo in absolute concentrations (25 ± 6 versus 16 ± 3 pg/mL). Only interleukin-1α possibly fulfills the criteria which would be expected from a substance to be released in response to RIPC and to protect the myocardium during ischemic cardioplegic arrest.

Oxidative Phospholipidomics in health and disease: Achievements, challenges and hopes

Phospholipid peroxidation products are recognized as important bioactive lipid mediators playing an active role as modulators in signalling events in inflammation, immunity and infection. The biochemical responses are determined by the oxidation structural features present in oxPL modulating biophysical and biological properties in model membranes and lipoproteins. In spite of the extensive work conducted with model systems over the last 20 years, the study of oxPL in biological systems has virtually stagnated. In fact, very little is known concerning the predominant oxPL in fluids and tissues, their basal levels, and any variations introduced with age, gender and ethnicity in health and disease. In consequence, knowledge on oxPL has not yet translated into clinical diagnostic, in the early and timely diagnosis of "silent" diseases such as atherosclerosis and cardiovascular diseases, or as prognosis tools in disease stratification and particularly useful in the context of multimorbidities. Their use as therapeutic solutions or the development of innovative functional biomaterials remains to be explored. This review summarizes the achievements made in the identification of oxPL revealing an enormous structural diversity. A brief overview of the challenges associated with the analysis of such diverse array of products is given and a critical evaluation on key aspects in the analysis pipeline that need to be addressed. Once these issues are addressed, Oxidative Phospholipidomics will hopefully lead to major breakthrough discoveries in biochemistry, pharmaceutical, and clinical areas for the upcoming 20 years. This article is part of Special Issue entitled 4-Hydroxynonenal and Related Lipid Oxidation Products.

Pleiotropic effects of oxidized phospholipids

Oxidized phospholipids (OxPLs) are increasingly recognized to play a role in a variety of normal and pathological states. OxPLs were implicated in regulation of inflammation, thrombosis, angiogenesis, endothelial barrier function, immune tolerance and other important processes. Rapidly accumulating evidence suggests that OxPLs are biomarkers of atherosclerosis and other pathologies. In addition, successful application of experimental drugs based on structural scaffold of OxPLs in animal models of inflammation was recently reported. This review briefly summarizes current knowledge on generation, methods of quantification and biological activities of OxPLs. Furthermore, receptor and cellular mechanisms of these effects are discussed. The goal of the review is to give a broad overview of this class of lipid mediators inducing pleiotropic biological effects.

Cellular and Molecular Mechanisms of Diabetic Atherosclerosis: Herbal Medicines as a Potential Therapeutic Approach

An increasing number of patients diagnosed with diabetes mellitus eventually develop severe coronary atherosclerosis disease. Both type 1 and type 2 diabetes mellitus increase the risk of cardiovascular disease associated with atherosclerosis. The cellular and molecular mechanisms affecting the incidence of diabetic atherosclerosis are still unclear, as are appropriate strategies for the prevention and treatment of diabetic atherosclerosis. In this review, we discuss progress in the study of herbs as potential therapeutic agents for diabetic atherosclerosis.

SSeCKS/AKAP12 scaffolding functions suppress B16F10-induced peritoneal metastasis by attenuating CXCL9/10 secretion by resident fibroblasts

SSeCKS/Gravin/AKAP12 (SSeCKS) is a kinase scaffolding protein known to suppress metastasis by attenuating tumor-intrinsic PKC- and Src-mediated signaling pathways [1]. In addition to downregulation in metastatic cells, in silico analyses identified SSeCKS downregulation in prostate or breast cancer-derived stroma, suggesting a microenvironmental cell role in controlling malignancy. Although orthotopic B16F10 and SM1WT1[Braf^V600E] mouse melanoma tumors grew similarly in syngeneic WT or SSeCKS-null (KO) mice, KO hosts exhibited 5- to 10-fold higher levels of peritoneal metastasis, and this enhancement could be adoptively transferred by pre-injecting naïve WT mice with peritoneal fluid (PF), but not non-adherent peritoneal cells (PC), from naïve KO mice. B16F10 and SM1WT1 cells showed increased chemotaxis to KO-PF compared to WT-PF, corresponding to increased PF levels of multiple inflammatory mediators, including the Cxcr3 ligands, Cxcl9 and 10. Cxcr3 knockdown abrogated enhanced chemotaxis to KO-PF and peritoneal metastasis in KO hosts. Conditioned media from KO peritoneal membrane fibroblasts (PMF), but not from KO-PC, induced increased B16F10 chemotaxis over controls, which could be blocked with Cxcl10 neutralizing antibody. KO-PMF exhibited increased levels of the senescence markers, SA-β-galactosidase, p21^waf1 and p16^ink4a, and enhanced Cxcl10 secretion induced by inflammatory mediators, lipopolysaccharide, TNFα, IFNα and IFNγ. SSeCKS scaffolding-site mutants and small molecule kinase inhibitors were used to show that the loss of SSeCKS-regulated PKC, PKA and PI3K/Akt pathways are responsible for the enhanced Cxcl10 secretion. These data mark the first description of a role for stromal SSeCKS/AKAP12 in suppressing metastasis, specifically by attenuating signaling pathways that promote secretion of tumor chemoattractants in the peritoneum.

Hepatic JAK2 protects against atherosclerosis through circulating IGF-1

Atherosclerosis is considered both a metabolic and inflammatory disease; however, the specific tissue and signaling molecules that instigate and propagate this disease remain unclear. The liver is a central site of inflammation and lipid metabolism that is critical for atherosclerosis, and JAK2 is a key mediator of inflammation and, more recently, of hepatic lipid metabolism. However, precise effects of hepatic Jak2 on atherosclerosis remain unknown. We show here that hepatic Jak2 deficiency in atherosclerosis-prone mouse models exhibited accelerated atherosclerosis with increased plaque macrophages and decreased plaque smooth muscle cell content. JAK2's essential role in growth hormone signalling in liver that resulted in reduced IGF-1 with hepatic Jak2 deficiency played a causal role in exacerbating atherosclerosis. As such, restoring IGF-1 either pharmacologically or genetically attenuated atherosclerotic burden. Together, our data show hepatic Jak2 to play a protective role in atherogenesis through actions mediated by circulating IGF-1 and, to our knowledge, provide a novel liver-centric mechanism in atheroprotection.