The role of chemokines in human cardiovascular pathology: enhanced biological insights

A Pilot Study About the Role of PANoptosis-Based Genes in Atherosclerosis Development

Background

As a chronic inflammatory disease, atherosclerosis (AS) and ischemia events are primarily affected by inflammation in AS. PANoptosis has been implicated in many human systemic disorders, including infection, cancer, neurodegeneration, and inflammation. On the other hand, little is understood about PANoptosis's function in AS.

Methods

We used consensus clustering to divide the GSE100927 dataset into two panoptosis-related subgroups. PANoptosis-associated genes were screened by differential analysis and weighted gene co-expression network analysis (WGCNA) and enriched by ClueGO software. Investigating LASSO regression and MCODE to identify AS Diagnostic Markers. Immunoinfiltration analysis and single-cell analysis were used to search for cell types associated with the diagnostic genes. Final validation was performed by polymerase chain reaction (PCR).

Results

We classified the GSE100927 dataset into two PANoptosis-related subtypes based on the expression of PANoptosis-related genes (PRGs) using consensus clustering. A total of 36 PANoptosis-associated genes were screened in the differentially expressed genes and WGCNA-related module. 4 hub genes were identified by MCODE and LASSO regression, and 3 AS diagnostic markers (ACP5, CCL3, HMOX1) were screened by external validation set. Immunoinfiltration analysis and single-cell analysis showed that the three diagnostic markers were associated with macrophages, and PCR results demonstrated that ACP5 and HMOX1 could be used as AS diagnostic markers.

Conclusion

Our study identified ACP5 and HMOX1 as diagnostic genes for AS that may be associated with PANoptosis. ACP5 and HMOX1 may be involved in the pathogenesis of AS by regulating macrophage PANoptosis.

Metformin beyond an anti-diabetic agent: A comprehensive and mechanistic review on its effects against natural and chemical toxins

In addition to the anti-diabetic effect of metformin, a growing number of studies have shown that metformin has some exciting properties, such as anti-oxidative capabilities, anticancer, genomic stability, anti-inflammation, and anti-fibrosis, which have potent, that can treat other disorders other than diabetes mellitus. We aimed to describe and review the protective and antidotal efficacy of metformin against biologicals, chemicals, natural, medications, pesticides, and radiation-induced toxicities. A comprehensive search has been performed from Scopus, Web of Science, PubMed, and Google Scholar databases from inception to March 8, 2023. All in vitro, in vivo, and clinical studies were considered. Many studies suggest that metformin affects diseases other than diabetes. It is a radioprotective and chemoprotective drug that also affects viral and bacterial diseases. It can be used against inflammation-related and apoptosis-related abnormalities and against toxins to lower their effects. Besides lowering blood sugar, metformin can attenuate the effects of toxins on body weight, inflammation, apoptosis, necrosis, caspase-3 activation, cell viability and survival rate, reactive oxygen species (ROS), NF-κB, TNF-α, many interleukins, lipid profile, and many enzymes activity such as catalase and superoxide dismutase. It also can reduce the histopathological damages induced by many toxins on the kidneys, liver, and colon. However, clinical trials and human studies are needed before using metformin as a therapeutic agent against other diseases.

Early Manifestation of Clozapine-Induced Cardiotoxicity: Detection, Pathophysiology, and Management

Schizoaffective disorder, bipolar type is a chronic mental health disorder that may manifest as mania. Clozapine is effective in treating acute mania and in achieving mood stabilization. However, on rare occasions, the use of clozapine has been associated with cardiotoxicity. Here, we present a case of a 31-year-old man who at baseline is known to have schizoaffective disorder, bipolar type, and cannabis dependence and was admitted to our hospital with a psychotic relapse. He was treated with clozapine, uptitrated to a maximum daily dose of 200mg twice daily by day 10. Thereafter he became febrile and experienced malaise, myalgias, and chest pain. He was noted on electrocardiogram to have sinus tachycardia without ischemic changes. In this context, he had a troponin leak, increased white blood cell count, serologies and cultures were negative and chest x-ray revealed no acute disease of the chest. Due to the suspicion of clozapine-induced cardiotoxicity, a transthoracic echocardiogram was done, which revealed mildly depressed left ventricular (LV) systolic function without pericardial effusion. Thereafter, clozapine was withdrawn and switched to lithium. Additionally, the cardioselective, metoprolol tartrate was initiated. Within 36-48 hours, he had resolution of symptoms and remained cardiovascularly stable. Clozapine uncommonly causes cardiotoxicity and early features may be non-specific. Awareness of this and recognizing early features aids in reducing the associated cardiovascular morbidity and mortality.

Chemokine (C-C Motif) Ligand 2/Chemokine Receptor 2 (CCR2) Axis Blockade to Delay Chondrocyte Hypertrophy as a Therapeutic Strategy for Osteoarthritis

Background

Chondrocytes play a vital role in the later stages of osteoarthritis (OA). The roles of chemokine (C-C motif) ligand 2 (CCL2) and its receptor, chemokine receptor 2 (CCR2), are as yet poorly elucidated in chondrocyte hypertrophy (CH). Here, we aimed to regulate the CCL2/CCR2 axis and explore its effect on progression of CH.

Material/Methods

Chondrocytes isolated from patients with OA were used in the present study. In vitro experiments were conducted to test hypertrophic gene and CCL2/CCR2 expression in chondrocyte degeneration caused by interleukin (IL)-17A or CCL2 protein stimulation. In addition, inhibition of CCL2 and CCR2 was used to assess the role of CCL2 and CCR2 blockade in CH. Relative gene expression was determined with real-time polymerase chain reaction, western blot, or immunofluorescence. Hypertrophic changes were assessed with cell area measurement. Moreover, the viability of chondrocytes was analyzed using an MTT assay and flow cytometry was used to assess cell apoptosis.

Results

CCL2 and CCR2 were upregulated in IL-17A-treated chondrocytes. The exogenic CCL2 stimulation also promoted CH and increased the expression of Type 10 collagen, RUNX2, and IHH, which could be reversed via suppression of CCR2. Inhibition of CCL2 and CCR2 expression was sufficient to: 1) protect Type 2 collagen synthesis; 2) alleviate IL-17A-induced overexpression of Type 10 collagen, RUNX2, and IHH; and 3) improve chondrocyte proliferation and apoptosis.

Conclusions

Blockading the CCL2/CCR2 axis plays a role in delaying the development of CH.

Pentosan polysulfate sodium prevents functional decline in chikungunya infected mice by modulating growth factor signalling and lymphocyte activation

Chikungunya virus (CHIKV) is an arthropod-borne virus that causes large outbreaks world-wide leaving millions of people with severe and debilitating arthritis. Interestingly, clinical presentation of CHIKV arthritides have many overlapping features with rheumatoid arthritis including cellular and cytokine pathways that lead to disease development and progression. Currently, there are no specific treatments or vaccines available to treat CHIKV infections therefore advocating the need for the development of novel therapeutic strategies to treat CHIKV rheumatic disease. Herein, we provide an in-depth analysis of an efficacious new treatment for CHIKV arthritis with a semi-synthetic sulphated polysaccharide, Pentosan Polysulfate Sodium (PPS). Mice treated with PPS showed significant functional improvement as measured by grip strength and a reduction in hind limb foot swelling. Histological analysis of the affected joint showed local inflammation was reduced as seen by a decreased number of infiltrating immune cells. Additionally, joint cartilage was protected as demonstrated by increased proteoglycan staining. Using a multiplex-immunoassay system, we also showed that at peak disease, PPS treatment led to a systemic reduction of the chemokines CXCL1, CCL2 (MCP-1), CCL7 (MCP-3) and CCL12 (MCP-5) which may be associated with the reduction in cellular infiltrates. Further characterisation of the local effect of PPS in its action to reduce joint and muscle inflammation was performed using NanoString™ technology. Results showed that PPS altered the local expression of key functional genes characterised for their involvement in growth factor signalling and lymphocyte activation. Overall, this study shows that PPS is a promising treatment for alphaviral arthritis by reducing inflammation and protecting joint integrity.

Atypical antipsychotics and oxidative cardiotoxicity: review of literature and future perspectives to prevent sudden cardiac death

Oxidative stress is considered the principal mediator of myocardial injury under pathological conditions. It is well known that reactive oxygen (ROS) or nitrogen species (RNS) are involved in myocardial injury and repair at the same time and that cellular damage is generally due to an unbalance between generation and elimination of the free radicals due to an inadequate mechanism of antioxidant defense or to an increase in ROS and RNS. Major adverse cardiovascular events are often associated with drugs with associated findings such as fibrosis or inflammation of the myocardium. Despite efforts in the preclinical phase of the development of drugs, cardiotoxicity still remains a great concern. Cardiac toxicity due to second-generation antipsychotics (clozapine, olanzapine, quetiapine) has been observed in preclinical studies and described in patients affected with mental disorders. A role of oxidative stress has been hypothesized but more evidence is needed to confirm a causal relationship. A better knowledge of cardiotoxicity mechanisms should address in the future to establish the right dose and length of treatment without impacting the physical health of the patients.

Human T-Cell Leukemia Virus Type 1 Infection Is a Risk Factor for Atherosclerosis

Background

Infection, such as by human immunodeficiency virus (HIV), has been reported to cause atherosclerosis by inducing inflammation. Because human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus, as is HIV, we investigated the possible influence of HTLV-1 on the pathogenesis of atherosclerosis by use of established atherosclerosis parameters.

Methods

The study was done on Iki Island, Fukuoka, an area endemic for HTLV-1. The data of 1,424 residents who reported to an annual health check were available for analysis. Anti-HTLV-1 antibody status and factors associated with atherosclerosis were examined, including maximum intima-media thickness (Max-IMT) and brachial-ankle pulse wave velocity (PWV).

Results

HTLV-1 positive participants had significantly higher Max-IMT (1.15 ± 0.55 vs. 1.08 ± 0.61 mm, P = 0.04) and PWV (1,760.6 ± 414.5 vs. 1,657.1 ± 425.5 cm/s, P < 0.01) values than did those negative. Moreover, in multiple regression analysis (odds ratio: 1.39, P < 0.01) of participants with Max-IMT 1.1 mm or over, HTLV-1 was extracted as an independent factor for the development of atherosclerosis.

Conclusion

Our results indicate that HTLV-1 infection confers a high risk of atherosclerosis, although its opposite relation is also possible. It is important to carefully follow the health status of HTLV-1 carriers.

Ameliorative effects of pregabalin on LPS induced endothelial and cardiac toxicity

We investigated the antioxidant, anti-inflammatory and anti-apoptotic effects of pregabalin (PREG) on lipopolysaccharide (LPS) induced sepsis related cardiotoxicity via NF-kβ pathways. We used 24 female Wistar albino rats divided into three groups: control, LPS treated and LPS + PREG treated. Total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), tumor necrosis factor alpha (TNF-α), nuclear factor kappa beta (NF-kβ)/p65, p-NF-kβ/p65, caspase-3 (Cas-3) and cleaved Cas-3 were measured in cardiac tissues and creatine kinase MB (CKMB), aspartate aminotransferase (AST), lactate dehydrogenase (LDH) levels were measured in blood samples. Also, Cas-3, granulocyte-colony stimulating factors (G-CSF), interleukin-6 (IL-6), serum amyloid A (SAA) and inducible nitric oxide synthase (iNOS) were measured immunohistochemically in heart and aorta tissue. In the LPS group; the levels of CKMB, AST, LDH, TOS, OSI increased and TAS decreased. TNF-α, p-NF-kβ/p65 and Cas-3 protein levels also increased in the LPS group. Immunohistochemical evaluation of the heart and aorta revealed a significant increase in the levels of Cas-3, G-CSF, SAA, IL-6 and iNOS in the LPS group. PREG treatment restored all measurements to near normal. LPS induced cardiovascular toxicity was due to inflammation, oxidative stress and apoptosis. PREG ameliorated the damage by inhibition of NF-kβ phosphorylation.

Polydatin for treating atherosclerotic diseases: A functional and mechanistic overview

With the advancement of science and technology, the living standards of human beings have continuously improved, but the incidence and mortality from atherosclerosis worldwide have also increased by year. Although interventional surgery and the continuous development of new drugs have significant therapeutic effects, their side effects cannot be ignored. Polydatin, an active ingredient isolated from the natural medicine Polygonum cuspidatum, has been shown to have a prominent role in the treatment of cardiovascular diseases. Polydatin treats atherosclerosis mainly from three aspects: anti-inflammatory, regulating lipid metabolism and anti-oxidative stress. This article will review the pharmacological mechanism of polydatin in anti-atherosclerosis, the biological characteristics of Polygonum cuspidatum, the toxicology and pharmacokinetics of polydatin and will provide ideas for further research.

Interferon regulatory factor 7 mediates obesity-associated MCP-1 transcription

Hypertrophy, associated with adipocyte dysfunction, causes increased pro-inflammatory adipokine, and abnormal glucose and lipid metabolism, leading to insulin resistance and obesity-related-health problems. By combining DNA microarray and genomic data analyses to predict DNA binding motifs, we identified the transcription factor Interferon Regulatory Factor 7 (IRF7) as a possible regulator of genes related to adipocyte hypertrophy. To investigate the role of IRF7 in adipocytes, we examined gene expression patterns in 3T3-L1 cells infected with a retrovirus carrying the IRF7 gene and found that enforced IRF7 expression induced the expression of monocyte chemoattractant protein-1 (MCP-1), a key initial adipokine in the chronic inflammation of obesity. CRISPR/Cas9 mediated-suppression of IRF7 significantly reduced MCP-1 mRNA. Luciferase assays, chromatin immunoprecipitation PCR analysis and gel shift assay showed that IRF7 transactivates the MCP-1 gene by binding to its proximal Interferon Stimulation Response Element (ISRE), a putative IRF7 binding motif. IRF7 knockout mice exhibited lower expression of MCP-1 in epidydimal white adipose tissue under high-fat feeding conditions, suggesting the transcription factor is physiologically important for inducing MCP-1. Taken together, our results suggest that IRF7 transactivates MCP-1 mRNA in adipocytes, and it may be involved in the adipose tissue inflammation associated with obesity.

Interleukin-8 in Hyperlipidemia and Coronary Heart Disease in Thai Patients Taking Statin Cholesterol-Lowering Medication While Undergoing Coronary Artery Bypass Grafting Treatment

The role of interleukin-8 (IL-8), a pivotal chemokine in atherogenesis and coronary heart disease (CHD) development, is diverse and remains unclear. This cross-sectional study investigates the association of the IL-8 expression in hyperlipidemia (H) and CHD patients who have been treated with statin cholesterol-lowering drugs while undergoing coronary artery bypass grafting treatment. Fifty-five Thai volunteers including 13 normal (N), 24 H, and 18 CHD patients were enrolled for the investigation. All the CHD patients had been treated continuously with statin cholesterol-lowering medications since the disease was diagnosed and were undergoing coronary bypass grafting approximately one month later. Therefore, the CHD group was representative of a pathogenesis improvement in CHD. The IL8 mRNA expression was determined by real-time quantitative PCR in the peripheral blood mononuclear cells from heparinized blood. The plasma IL-8 levels were assessed by enzyme-linked immunosorbent assay. The result shows that the IL8 mRNA expression in the H group tended to increase; however, in the CHD group, there was a significant decrease (p=0.0111) compared to the N group. The IL8 mRNA expression and the plasma levels in the CHD group were significantly lower than those in the H group (p < 0.05). A significant negative correlation between the IL8 mRNA (r = -0.499) or plasma IL-8 (r = -0.3875) expression and CHD progression was observed (p < 0.05). In conclusion, the transcriptomic and the phenotypic IL-8 expression decreased significantly in the Thai CHD patients who had continuously received statin-group medications compared to the H and N group participants. Therefore, IL-8 should serve as a feasible marker and could be used to evaluate the therapeutic effects of statins and illustrate the pathology of CHD treatment.

Increased circulating interleukin-8 levels in systemic lupus erythematosus patients: a meta-analysis

AIM

We performed this meta-analysis in order to evaluate circulating interleukin-8 (IL-8) levels in systemic lupus erythematosus (SLE) patients more accurately and explore its related influencing factors.

METHODS

The related literature was systematically searched in PubMed, Embase and The Cochrane Library database (up to 28 March 2018). All data analysis was performed by Stata 12.0 software.

RESULTS

The results showed SLE patients had a higher circulating IL-8 levels than normal controls (pooled standardized mean difference = 0.963; 95% CI: 0.416-1.511). Subgroup analyses indicated SLE patients with age <40 years, Asia group and disease duration <10 years had higher IL-8 levels.

CONCLUSION

Compared with normal controls, circulating IL-8 levels in SLE patients are elevated and affected by age, region and disease duration.

7-Ketocholesterol enhances leukocyte adhesion to endothelial cells via p38MAPK pathway

7-Ketocholesterol is a major dietary cholesterol oxidation product found in high concentrations in atherosclerotic plaques, which contribute to the development of atherosclerosis. This study aimed to investigate the effects of 7-ketocholesterol on endothelial inflammation, as well as the underlying mechanisms. Pretreatment of human umbilical vein endothelial cells (HUVEC) with 7-ketocholesterol significantly enhanced the total interactions between human monocytic cells (THP-1 cell line) and TNFα-activated HUVECs under physiological flow conditions, compared to pretreatment with cholesterol (TNFα+50 μM cholesterol: 13.1 ± 0.54 cells/CPF, TNFα+50 μM 7-ketocholesterol: 18.9 ± 0.35 cells/CPF, p < 0.01). 7-Ketocholesterol enhanced the expression of E-selectin, ICAM-1, and VCAM-1 proteins. It also activated p38 mitogen-activated protein kinase (MAPK), and treatment with a p38 MAPK inhibitor inhibited both E-selectin expression via ATF-2 activation and 7-ketocholesterol-induced THP-1 adhesion to HUVECs. These findings suggest that 7-ketocholesterol enhances leukocyte–endothelial interactions by upregulating the expression of adhesion molecules, presumably via the p38 MAPK-dependent pathway.

Inflammatory Profiles of the Interleukin Family and Network in Cerebral Hemorrhage

Cerebral hemorrhage is a series of devastating cerebrovascular diseases with high mortality, morbidity and recurrence rate. Localized and systemic immuno-reactions are involved. Aggregation of immunocytes, which were both recruited from the peripheral circulation and resident in the central nervous system, is induced and activated by hematoma-related blood components. Subsequently, various cytokines, chemokines, free radicals and toxic chemicals are secreted to participant host defense responses. Among these, neuro-inflammation plays critical roles in both the pathologic processes of secondary injuries and recovery of neural damages. Numerous treatment strategies have been proposed, aiming at controlling the balance between anti- and proinflammation. Here, we summarized our current understanding and potential clinical applications for cytokines of the interleukin family in the pathogenesis of hemorrhagic stroke. In addition, we conducted protein-protein network, gene ontology and KEGG analysis on the interleukins using online bioinformatic tools to further elaborate the comprehensive mechanisms of interleukins in cerebral hemorrhage.

Cellular senescence links aging and diabetes in cardiovascular disease

Aging is a powerful independent risk factor for cardiovascular diseases such as atherosclerosis and heart failure. Concomitant diabetes mellitus strongly reinforces this effect of aging on cardiovascular disease. Cellular senescence is a fundamental mechanism of aging and appears to play a crucial role in the onset and prognosis of cardiovascular disease in the context of both aging and diabetes. Senescent cells are in a state of cell cycle arrest but remain metabolically active by secreting inflammatory factors. This senescence-associated secretory phenotype is a trigger of chronic inflammation, oxidative stress, and decreased nitric oxide bioavailability. A complex interplay between these three mechanisms results in age- and diabetes-associated cardiovascular damage. In this review, we summarize current knowledge on cellular senescence and its secretory phenotype, which might be the missing link between aging and diabetes contributing to cardiovascular disease.

Impact of phenolic-rich olive leaf extract on blood pressure, plasma lipids and inflammatory markers: a randomised controlled trial

PURPOSE

Dietary polyphenols have been demonstrated to favourably modify a number of cardiovascular risk markers such as blood pressure (BP), endothelial function and plasma lipids. We conducted a randomised, double-blind, controlled, crossover trial to investigate the effects of a phenolic-rich olive leaf extract (OLE) on BP and a number of associated vascular and metabolic measures.

METHODS

A total of 60 pre-hypertensive [systolic blood pressure (SBP): 121-140 mmHg; diastolic blood pressure (DBP): 81-90 mmHg] males [mean age 45 (±SD 12.7 years, BMI 26.7 (±3.21) kg/m2] consumed either OLE (136 mg oleuropein; 6 mg hydroxytyrosol) or a polyphenol-free control daily for 6 weeks before switching to the alternate arm after a 4-week washout.

RESULTS

Daytime [-3.95 (±SD 11.48) mmHg, p = 0.027] and 24-h SBP [-3.33 (±SD 10.81) mmHg, p = 0.045] and daytime and 24-h DBP [-3.00 (±SD 8.54) mmHg, p = 0.025; -2.42 (±SD 7.61) mmHg, p = 0.039] were all significantly lower following OLE intake, relative to the control. Reductions in plasma total cholesterol [-0.32 (±SD 0.70) mmol/L, p = 0.002], LDL cholesterol [-0.19 (±SD 0.56) mmol/L, p = 0.017] and triglycerides [-0.18 (±SD 0.48), p = 0.008] were also induced by OLE compared to control, whilst a reduction in interleukin-8 [-0.63 (±SD 1.13) pg/ml; p = 0.026] was also detected. Other markers of inflammation, vascular function and glucose metabolism were not affected.

CONCLUSION

Our data support previous research, suggesting that OLE intake engenders hypotensive and lipid-lowering effects in vivo.

Visual Field Progression is Associated with Systemic Concentration of Macrophage Chemoattractant Protein-1 in Normal-Tension Glaucoma

PURPOSE

To investigate the associations between endothelin-1 (ET-1) and macrophage chemoattractant protein-1 (MCP-1) levels and visual field (VF) progression in normal-tension glaucoma (NTG).

METHODS

We conducted a prospective, longitudinal study in 71 patients with NTG. Blood samples from all subjects were assayed for ET-1 and MCP-1 concentrations, and baseline ophthalmic examinations, including the VF, were performed. Baseline data were compared with follow-up data over 3 years.

RESULTS

After 3 years of follow-up, 14 of the 71 patients showed VF progression, and the systemic MCP-1 level was significantly associated with VF progression (r = 0.318, p = 0.007). Multiple regression analysis showed that VF progression was significantly associated with MCP-1 (odds ratio, OR = 1.021, 95% CI = 1.003-1.040; p = 0.020) and optic disc hemorrhage (ODH; OR = 1.573; 95% CI = 1.140-2.170; p = 0.023).

CONCLUSIONS

Systemic MCP-1 levels were associated with VF progression in patients with NTG.

Tryptanthrin Suppresses the Activation of the LPS-Treated BV2 Microglial Cell Line via Nrf2/HO-1 Antioxidant Signaling

Microglia are the resident macrophages in the central nervous system (CNS) and play essential roles in neuronal homeostasis and neuroinflammatory pathologies. Recently, microglia have been shown to contribute decisively to neuropathologic processes after ischemic stroke. Furthermore, natural compounds have been reported to attenuate inflammation and pathologies associated with neuroinflammation. Tryptanthrin (indolo[2,1-b]quinazoline-6,12-dione) is a phytoalkaloid with known anti-inflammatory effects in cells. In present study, the authors confirmed middle cerebral artery occlusion (MCAO) injury triggers the activation of microglia in brain tissue, and investigated whether tryptanthrin influences the function of mouse murine BV2 microglia under LPS-induced inflammatory conditions in vitro. It was found tryptanthrin protected BV2 microglia cells against LPS-induced inflammation and inhibited the induction of M1 phenotype microglia under inflammatory conditions. In addition, tryptanthrin reduced the production of pro-inflammatory cytokines in BV2 microglia cells via nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) signaling and NF-κB signaling. The authors suggest that tryptanthrin might alleviate the progress of neuropathologies by controlling microglial functions under neuroinflammatory conditions.

A three-dimensional in vitro model to demonstrate the haptotactic effect of monocyte chemoattractant protein-1 on atherosclerosis-associated monocyte migration

Monocyte transendothelial migration is a multi-step process critical for the initiation and development of atherosclerosis. The chemokine monocyte chemoattractant protein-1 (MCP-1) is overexpressed during atheroma and its concentration gradients in the extracellular matrix (ECM) is critical for the transendothelial recruitment of monocytes. Based on prior observations, we hypothesize that both free and bound gradients of MCP-1 within the ECM are involved in directing monocyte migration. The interaction between a three-dimensional (3D), cell-free, collagen matrix and MCP-1; and its effect on monocyte migration was measured in this study. Our results showed such an interaction existed between MCP-1 and collagen, as 26% of the total MCP-1 added to the collagen matrix was bound to the matrix after extensive washes. We also characterized the collagen-MCP-1 interaction using biophysical techniques. The treatment of the collagen matrix with MCP-1 lead to increased monocyte migration, and this phenotype was abrogated by treating the matrix with an anti-MCP-1 antibody. Thus, our results indicate a binding interaction between MCP-1 and the collagen matrix, which could elicit a haptotactic effect on monocyte migration. A better understanding of such mechanisms controlling monocyte migration will help identify target cytokines and lead to the development of better anti-inflammatory therapeutic strategies.

Artesunate attenuated progression of atherosclerosis lesion formation alone or combined with rosuvastatin through inhibition of pro-inflammatory cytokines and pro-inflammatory chemokines

BACKGROUNDS

Inflammation plays an important role in all stages of atherosclerosis, but little is known about the therapeutic effects of quenching inflammation in atherosclerotic lesions formation.

PURPOSE

Herein, the effect of artesunate, a derivant from artemisinin from the traditional Chinese herb sweet wormwood, could attenuate the progression of atherosclerosis lesion formation alone or combined with rosuvastatin in Western-type diet (WD) fed ApoE(-/-) mice, and explored its possible mechanisms.

METHODS

The methods such as ELISA for plasma lipids and cytokines analyses, qRT-PCR and western blot for mRNA and protein expressions, and MTT assay for human umbilical vein endothelial cells (HUVECs) viability were used for in vivo and in vitro experiments.

RESULTS

Artesunate could attenuate the progression of atherosclerosis lesion formation alone or combined with rosuvastatin in WD fed ApoE(-/-) mice without changes in food uptake, body weight and plasma lipids level, but with a significant reduction of pro-inflammatory cytokine, such as TNF-α and IL-6. Furthermore, artesunate could down-regulate the pro-inflammatory chemokines such as IL-8 and MCP-1 in aorta of mice. Besides, artesunate didn't influence IL-8 and MCP-1 secretion in HUVECs up-regulated by TNF-α, but inhibited IL-8 and MCP-1 secretion up-regulated by LPS.

CONCLUSION

AS attenuated progression of atherosclerosis lesion formation alone or combined with rosuvastatin through anti-inflammatory effect, resulting in down-regulation of TNF-α and IL-6, and further down-regulating IL-8 and MCP-1 expressions in aorta of WD fed ApoE(-/-) mice. Rosuvastatin combined with artesunate could more effectively attenuate the progression of atherosclerosis lesions than when treated by one of them, demonstrating that lipid-lowering agents combined with anti-inflammatory agents could provide the greater benefit for cardiovascular disease patients. Artesunate is worth further investigating as a candidate drug for the treatment of atherosclerosis.

Monocyte chemoattractant protein-1 and the kidney

PURPOSE OF REVIEW

Recently, initial studies have been carried out in patients using monocyte chemoattractant protein-1 (MCP-1) inhibitors. This review summarizes the known function of MCP-1 in regulating monocytes during inflammation and its role in inflammatory disease of the kidney.

RECENT FINDINGS

MCP-1 is one of the first chemokines described and plays an important role in renal inflammatory disease. The function of MCP-1 has been investigated and analyzed in both animal models of renal disease and renal patients. MCP-1 mediates firstly the release of monocytes from the bone marrow, and then generates a gradient in the endothelial glycocalyx to direct monocytes to sites of inflammation, thereby alleviating the migration of blood leukocytes into the inflamed tissue. In addition, MCP-1 has direct signaling effects in monocytes and influences migration, proliferation, and differentiation of leukocytes. Blockade of MCP-1 in several models of renal disease has ameliorated the disease, suggesting that inhibition of MCP-1 is a promising and valid strategy to treat patients with renal inflammatory disease.

SUMMARY

Understanding the role of MCP-1 in monocyte homeostasis and the implications of MCP-1 inhibition in renal disease will help in designing better diagnostic and therapeutic strategies in patients with inflammatory renal disease.

Effect of metformin and sitagliptin on doxorubicin-induced cardiotoxicity in adult male albino rats

The use of doxorubicin (DOX) as an antitumor therapeutic agent is limited due to its cardiotoxic effects. Metformin (Met) and sitagliptin (Sitg) are suggested to improve cardiac function. The present study aimed to determine the potential protective effects of Met and Sitg on DOX-induced cardiotoxicity. Rats were divided into six groups: groups I, II, and III received normal saline, Met, and Sitg, respectively. Groups IV, V, and VI received DOX only, Met + DOX, and Sitg + DOX, respectively. Heart tissue was used for biochemical assays which measured cardiac reduced glutathione (GSH), thiobarbituric acid reactive substances (TBARS), and tumor necrosis factor α (TNF-α). Serum creatinine kinase (CK) and lactate dehydrogenase (LDH) were also measured. The heart apex was prepared for histological (hematoxylin and eosin) and immunohistochemical examination. Intoxication of DOX was associated with a significant elevation in serum CK-MB and LDH, reduction in cardiac GSH, and increased TBARS and TNF-α compared to the controls. Administration of Met or Sitg to DOX-intoxicated rats suppressed serum CK-MB and LDH. Moreover, cardiac GSH was elevated with decreased TBARS and TNF-α. These results were confirmed by histological study. Met and Sitg caused inhibition of caspase 3 and upregulation of B-cell lymphoma 2 (Bcl-2) expression in DOX-intoxicated animals. Sitg was found to exert a significantly better protective effect compared to that of Met. It was concluded that Sitg might be more effective than Met in reducing myocardial injury in DOX-induced cardiotoxicity in rats.

Protective Effects of Carvedilol and Vitamin C against Azithromycin-Induced Cardiotoxicity in Rats via Decreasing ROS, IL1-β, and TNF-α Production and Inhibiting NF-κB and Caspase-3 Expression

The Food and Drug Administration recently warned of the fatal cardiovascular risks of azithromycin in humans. In addition, a recently published study documented azithromycin-induced cardiotoxicity in rats. This study aimed to justify the exact cardiovascular events accompanying azithromycin administration in rats, focusing on electrocardiographic, biochemical, and histopathological changes. In addition, the underlying mechanisms were studied regarding reactive oxygen species production, cytokine release, and apoptotic cell-death. Finally, the supposed protective effects of both carvedilol and vitamin C were assessed. Four groups of rats were used: (1) control, (2) azithromycin, (3) azithromycin + carvedilol, and (4) azithromycin + vitamin C. Azithromycin resulted in marked atrophy of cardiac muscle fibers and electrocardiographic segment alteration. It increased the heart rate, lactate dehydrogenase, creatine phosphokinase, malondialdehyde, nitric oxide, interleukin-1 beta (IL1-β), tumor necrosis factor alpha (TNF-α), nuclear factor kappa beta (NF-κB), and caspase-3. It decreased reduced glutathione, glutathione peroxidase, and superoxide dismutase. Carvedilol and vitamin C prevented most of the azithromycin-induced electrocardiographic and histopathological changes. Carvedilol and vitamin C decreased lactate dehydrogenase, malondialdehyde, IL1-β, TNF-α, NF-κB, and caspase-3. Both agents increased glutathione peroxidase. This study shows that both carvedilol and vitamin C protect against azithromycin-induced cardiotoxicity through antioxidant, immunomodulatory, and antiapoptotic mechanisms.

Propofol Attenuates Lipopolysaccharide-Induced Monocyte Chemoattractant Protein-1 Production Through Enhancing apoM and foxa2 Expression in HepG2 Cells

Monocyte chemoattractant protein-1 (MCP-1) is a cytokine that mediates the influx of cells to sites of inflammation. Our group recently reported that propofol exerted an anti-inflammatory effect and could inhibit lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokines. However, the effect and possible mechanisms of propofol on MCP-1 expression remain unclear. LPS-stimulated HepG2 cells were treated with 50 μM propofol for 0, 6, 12, and 24 h, respectively. The transcript and protein levels were measured by real-time quantitative PCR and Western blot analyses, respectively. We found that propofol markedly decreased both MCP-1 messenger RNA (mRNA) and protein levels in LPS-stimulated HepG2 cells in a time-dependent manner. Expression of apolipoprotein M (apoM) and forkhead box protein A2 (foxa2) was increased by propofol treatment in HepG2 cells. In addition, the inhibitory effect of propofol on MCP-1 expression was significantly abolished by small interfering RNA against apoM and foxa2 in LPS-stimulated HepG2 cells. Propofol attenuates LPS-induced MCP-1 production through enhancing apoM and foxa2 expression in HepG2 cells.

The role of MCP-1-CCR2 ligand-receptor axis in chondrocyte degradation and disease progress in knee osteoarthritis

BACKGROUND

Osteoarthritis (OA) is a common arthritic disease and multifactorial whole-joint disease. Interactions of chemokines and OA is inadequately documented.

RESULTS

In vivo and in vitro studies were conducted to investigate monocyte chemoattractant protein 1 (MCP-1) and receptor chemokine (C-C motif) receptor 2 (CCR2) in chondrocyte degradation and cartilage degeneration. Chondrocytes from 16 OA patients and 6 normal controls were involved in this study. After stimulation of MCP-1, the expression of MCP-1 and CCR2 increased significantly (P < 0.001) and the expression of MMP-13 also increased (P < 0.05). MCP-1 stimulation also induced (or enhanced) the apoptosis of OA chondrocytes (P < 0.05). Additionally, the degradation of cartilage matrix markers (metalloproteinase 3 and 13, MMP3 and MMP13) in the culture medium of normal chondrocytes was also assessed. Furthermore, intra-articular injection of MCP-1 in mouse knees induced cartilage degradation and the CCR2 antagonist did not impede cartilage destroy in rats knees of monosodium iodoacetate (MIA) model.

CONCLUSIONS

The results of this study demonstrate that the MCP-1-CCR2 ligand-receptor axis plays a special role in the initiation and progression of OA pathology. Patients with ambiguous etiology can gain some insight from the MCP-1-CCR2 ligand-receptor axis.

Elevated Circulating Interleukin 33 Levels in Stable Renal Transplant Recipients at High Risk for Cardiovascular Events

Background

The Major Adverse Cardiovascular Events calculator (CRCRTR-MACE) estimates the burden of cardiovascular risk in renal transplant recipients (RTR). Our recent study of 95 RTR reported the 7-year median risk of cardiovascular events (CVE) to be 9.97%, ranging from 1.93 to 84.27%. Nearly a third (28.4%) of the cohort was above 20% risk for a CVE. Since interleukins (ILs) as part of the inflammatory response may play a role in the pathogenesis of cardiovascular disease (CVD), we extended this study to identify which ILs are associated with high cardiovascular risk in this population.

Methods

Twenty-two ILs were measured by multiplexed fluorescent bead-based immunoassay in 95 RTR and 56 normal controls. Stepwise analysis after multivariate determination of significant demographic and inflammatory variables was performed between the high and low-CVD risk groups (which were arbitrarily set at scores <10% and ≥20%, respectively). Normalized data was presented as mean ± SD and non-normalized data as median (minimum–maximum). Significance was measured at <0.05.

Results

27.5% of the low-risk and 31.3% of the high-risk groups had mean IL levels above the 95 percentile of the normal control levels. In the non-parametric analysis IL-6, 9, 16, 17 and 33 were significantly higher in the high-risk group compared to the control. Univariate analysis (UVA) of the high-risk group identified IL-33 as the only IL that remained significantly higher than the control and low-risk groups (p = 0.000). The percentage of patients with IL-33 levels above the 90 percentile of control value in the low and high-risk groups were 15.6% and 52.0%, respectively (p<0.002). UVA of factors significant to high IL-33 levels included estimated glomerular filtration rate (eGFR), while diabetes mellitus, serum phosphorus, microalbuminuria and age also remained significant in the multivariate analysis.

Conclusion

Circulating IL-33 level is positively associated with high CRCRTR-MACE score. Diminished eGFR, age, diabetes, serum phosphorus and microalbuminurea demonstrate significant relationship with elevated IL-33 levels, supporting the possible pathognomonic role of IL-33 in the cardiovascular burden in RTR.

Effect of galantamine on adjuvant-induced arthritis in rats

Stimulation of the vagus nerve suppresses cytokine production and macrophage activation, via the interaction of its neurotransmitter acetylcholine (ACh) with the α7 subunit of the nicotinic acetylcholine receptor (α7nAChR), present on neurons and inflammatory cells. The present study aimed to verify the potential anti-inflammatory effect of galantamine against experimental arthritis induced in rats. Fourteen days post adjuvant injection, Sprague-Dawley rats were treated orally with three doses of galantamine (1.25, 2.5 and 5 mg/kg) or leflunomide (10 mg/kg) for 2 weeks and arthritis progression was assessed by hind paw swelling. Additionally, serum biomarkers, viz., anti-cyclic citrullinated peptide antibodies (Anti-CCP), tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10) and monocyte chemoattractant protein-1 (MCP-1) were measured. Radiological examination of the hind paws was also carried out to evaluate the degree of joint damage. Adjuvant arthritis led to a significant weight loss, marked swelling of the hind paw and alteration in the serum levels of anti-CCP, TNF-α, IL-10 and MCP-1. These alterations were associated with significant radiological changes of the joints. Galantamine, in a dose-dependent manner, reduced significantly all biomarkers of inflammation, with the highest dose showing the best beneficial anti-inflammatory effect that was superior in magnitude to the reference drug leflunomide in most of the studied parameters. In conclusion, these results suggest that galantamine may represent a novel, inexpensive and effective therapeutic strategy in the treatment of rheumatoid arthritis.

Secoiridoids delivered as olive leaf extract induce acute improvements in human vascular function and reduction of an inflammatory cytokine: a randomised, double-blind, placebo-controlled, cross-over trial

The leaves of the olive plant (Olea europaea) are rich in polyphenols, of which oleuropein and hydroxytyrosol (HT) are most characteristic. Such polyphenols have been demonstrated to favourably modify a variety of cardiovascular risk factors. The aim of the present intervention was to investigate the influence of olive leaf extract (OLE) on vascular function and inflammation in a postprandial setting and to link physiological outcomes with absorbed phenolics. A randomised, double-blind, placebo-controlled, cross-over, acute intervention trial was conducted with eighteen healthy volunteers (nine male, nine female), who consumed either OLE (51 mg oleuropein; 10 mg HT), or a matched control (separated by a 4-week wash out) on a single occasion. Vascular function was measured by digital volume pulse (DVP), while blood collected at baseline, 1, 3 and 6 h was cultured for 24 h in the presence of lipopolysaccharide in order to investigate effects on cytokine production. Urine was analysed for phenolic metabolites by HPLC. DVP-stiffness index and ex vivo IL-8 production were significantly reduced (P< 0.05) after consumption of OLE compared to the control. These effects were accompanied by the excretion of several phenolic metabolites, namely HT and oleuropein derivatives, which peaked in urine after 8-24 h. The present study provides the first evidence that OLE positively modulates vascular function and IL-8 production in vivo, adding to growing evidence that olive phenolics could be beneficial for health.

Activation of lymphotoxin-beta receptor enhances the LPS-induced expression of IL-8 through NF-κB and IRF-1

Lymphotoxin-beta receptor (LTβR), a receptor for LIGHT and LTα1β2, is expressed on the epithelial, stromal, and myeloid cells. LTβR is known to affect the lymphoid organ development and immune homeostasis. However, its role in macrophage function has not been sufficiently elucidated. The effect of LTβR stimulation in the inflammatory activation of macrophages was investigated by treating the human macrophage-like cell line THP-1 with LTβR-specific monoclonal antibody. Interestingly, combined treatment with anti-LTβR antibody and LPS caused the synergistic induction of IL-8 expression at the transcriptional level. Analysis indicated that nuclear factor (NF)-κB activity was enhanced via the mitogen-activated protein kinase (MAPK) and glycogen synthase kinase (GSK)-3β/cAMP response element binding protein (CREB) pathways. In addition, LTβR stimulation induced the expression of interferon regulatory factor (IRF)-1, one of the major transcription factors of IL-8 gene. Down-regulation of IRF-1 expression reduced the enhancing effect caused by LTβR stimulation. This indicates that the LTβR stimulation enhances the LPS-induced expression of IL-8 via the combined action of NF-κB and IRF-1.

Proinflammatory status in the aqueous humor of high myopic cataract eyes

High myopia has long been recognized as an inflammation-related disease, and high myopic eyes are thought to have a proinflammatory internal microenvironment, which might predispose to the occurrence of certain inflammation-related complications such as fibrotic capsular contraction syndrome after cataract surgery. Therefore, the purpose of this study was to detect inflammatory cytokines expressed in the aqueous humor (AH) of high myopic cataract (HMC) patients. The cytokines were screened using a RayBio Human Cytokine Antibody Array in AH samples from 15 age-related cataract (ARC) patients and 15 HMC patients. Those detected by the screening assays were verified using a Bio-Plex Suspension Array System in AH samples from 35 ARC patients and 45 HMC patients. The cytokine antibody array showed that the expression level of interleukin-1 receptor antagonist (IL-1ra) in the AH was higher in ARC than in HMC, whereas opposite trends were found for monocyte chemoattractant protein-1 (MCP-1), regulated on activation, normal T-cell expressed and presumably secreted (RANTES), IL-8, platelet-derived growth factor-BB, and IL-6 (all P < 0.05). In the verification assay using the suspension cytokine array, only the expression levels of IL-1ra and MCP-1 were significantly different between the ARC and HMC groups (P = 0.014 and 0.038, respectively); these results were confirmed by western blot assays. Our results demonstrated that the expression of IL-1ra was significantly lower and the expression of MCP-1 was significantly higher in the AH of HMC than in ARC, suggestive of a proinflammatory status in the anterior chamber of HMC eyes.

p-Cresol affects reactive oxygen species generation, cell cycle arrest, cytotoxicity and inflammation/atherosclerosis-related modulators production in endothelial cells and mononuclear cells

Aims

Cresols are present in antiseptics, coal tar, some resins, pesticides, and industrial solvents. Cresol intoxication leads to hepatic injury due to coagulopathy as well as disturbance of hepatic circulation in fatal cases. Patients with uremia suffer from cardiovascular complications, such as atherosclerosis, thrombosis, hemolysis, and bleeding, which may be partly due to p-cresol toxicity and its effects on vascular endothelial and mononuclear cells. Given the role of reactive oxygen species (ROS) and inflammation in vascular thrombosis, the objective of this study was to evaluate the effect of p-cresol on endothelial and mononuclear cells.

Methods

EA.hy926 (EAHY) endothelial cells and U937 cells were exposed to different concentrations of p-cresol. Cytotoxicity was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5 -diphenyltetrazolium bromide (MTT) assay and trypan blue dye exclusion technique, respectively. Cell cycle distribution was analyzed by propidium iodide flow cytometry. Endothelial cell migration was studied by wound closure assay. ROS level was measured by 2′,7′-dichlorofluorescein diacetate (DCF) fluorescence flow cytometry. Prostaglandin F_2α (PGF_2α), plasminogen activator inhibitor-1 (PAI-1), soluble urokinase plasminogen activator receptor (suPAR), and uPA production were determined by Enzyme-linked immunosorbant assay (ELISA).

Results

Exposure to 100–500 µM p-cresol decreased EAHY cell number by 30–61%. P-cresol also decreased the viability of U937 mononuclear cells. The inhibition of EAHY and U937 cell growth by p-cresol was related to induction of S-phase cell cycle arrest. Closure of endothelial wounds was inhibited by p-cresol (>100 µM). P-cresol (>50 µM) also stimulated ROS production in U937 cells and EAHY cells but to a lesser extent. Moreover, p-cresol markedly stimulated PAI-1 and suPAR, but not PGF_2α, and uPA production in EAHY cells.

Conclusions

p-Cresol may contribute to atherosclerosis and thrombosis in patients with uremia and cresol intoxication possibly due to induction of ROS, endothelial/mononuclear cell damage and production of inflammation/atherosclerosis-related molecules.

Clozapine-induced cardiotoxicity in rats: Involvement of tumour necrosis factor alpha, NF-κβ and caspase-3

Clozapine, an ideal antipsychotic drug for the treatment of resistant schizophrenia, is considered the most underutilised treatment for schizophrenia. However, safety concerns have been raised about clozapine-induced cardiotoxicity, which may lead to sudden death, particularly in young patients. The exact mechanism of clozapine cardiotoxicity has not yet been thoroughly studied. This study aimed to investigate the possible mechanisms of clozapine-induced cardiotoxicity in a rat model. Young male Wistar rats were treated with clozapine (10, 15 and 25 mg/kg/day, i.p.) for 21 days. Haemodynamic and echocardiographic studies were performed for assessment of cardiac functions. Heart sections were studied histopathologically and immunohistochemically. Serum and cardiac markers of cardiotoxicity, oxidative stress, inflammation and apoptosis were evaluated. Heart sections of CLZ-treated animals showed increased cardiac inflammation that correlated with the clozapine dose. Serum levels of CK-MB and LDH levels increased, as did cardiac levels of TNF-α, MDA, NO, myeloperoxidase (MPO), 8-OHdG, caspase-3 and NF-κB p65. In contrast, GSH levels and GSH-Px activity decreased. Furthermore, immunohistochemical examination of the heart sections showed positive immunostaining for both 3-nitrotyrosine and caspase-3 in all clozapine-treated groups. Clozapine, particularly in relatively high doses, has a clear cardiotoxic effect. This cardiotoxicity is accompanied by increased myocardial oxidative stress, inflammatory cytokines, DNA damage and apoptosis with attenuation in antioxidant defences, thus explaining the previously reported myocarditis and pericarditis during clozapine therapy in clinical studies.

Conditional deletion of cardiomyocyte peroxisome proliferator-activated receptor γ enhances myocardial ischemia-reperfusion injury in mice

The nuclear transcription factor peroxisome proliferator-activated receptor γ (PPARγ) is a key regulator of the inflammatory response to an array of biologic insults. We have previously demonstrated that PPARγ ligands reduce myocardial ischemia-reperfusion injury in rodents. In the current study, we directly determined the role of cardiomyocyte PPARγ in ischemia-reperfusion injury, using a model of conditional cardiomyocyte-specific deletion of PPARγ in vivo. In mice, α-myosin heavy chain-restricted Cre-mediated PPARγ deficiency was induced by tamoxifen treatment (30 mg/kg intraperitoneally) for 4 days (PPARγ mice), whereas controls included mice treated with the oil diluent vehicle (PPARγ mice). Western blot and histochemical analyses confirmed that expression of PPARγ protein was abolished in cardiomyocytes of mice treated with tamoxifen, but not with vehicle. After tamoxifen or vehicle treatment, animals were subjected to 30-min ligation of the left anterior descending coronary artery followed by 2-h reperfusion. In PPARγ mice, myocardial ischemia and reperfusion induced extensive myocardial damage, which was associated with elevated tissue activity of myeloperoxidase, indicating infiltration of neutrophils, and elevated plasma levels of troponin I when compared with PPARγ mice. Upon echocardiographic analysis, PPARγ mice also demonstrated ventricular dilatation and systolic dysfunction. Plasma levels of the proinflammatory cytokines interleukin 1β and interleukin 6 were higher in PPARγ mice when compared with PPARγ mice. These pathological events in PPARγ mice were associated with enhanced nuclear factor κB DNA binding in the infarcted hearts. Thus, our data suggest that cardiomyocyte PPARγ is a crucial protective receptor and may prevent reperfusion injury by modulating mechanisms of inflammation.

Lidocaine attenuates lipopolysaccharide-induced inflammatory responses in microglia

BACKGROUND

Lidocaine has been used as a local anesthetic with anti-inflammatory properties, but its effects on neuroinflammation have not been well defined. In the present study, we investigated the prophylactic effects of lidocaine on lipopolysaccharide (LPS)-activated microglia and explored the underlying mechanisms.

MATERIALS AND METHODS

Microglial cells were incubated with or without 1 μg/mL LPS in the presence or absence of lidocaine, a p38 mitogen-activated protein kinase (p38 MAPK) inhibitor (SB203580), a nuclear factor-kappa B (NF-κB) inhibitor (pyrrolidine dithiocarbamate), or small interfering RNA. The protein and expression levels of inflammatory mediators, such as monocyte chemotactic protein 1, nitric oxide, prostaglandin E2, interleukin 1β, and tumor necrosis factor α were measured using enzyme-linked immunosorbent assays and real-time polymerase chain reaction. The effect of lidocaine on NF-κB and p38 MAPK activation was evaluated using enzyme-linked immunosorbent assays, Western blot analysis, and electrophoretic mobility shift assay.

RESULTS

Lidocaine (≥2 μg/mL) significantly inhibited the release and expression of nitric oxide, monocyte chemotactic protein 1, prostaglandin E2, interleukin 1β, and tumor necrosis factor α in LPS-activated microglia. Treatment with lidocaine also significantly inhibited the phosphorylation of p38 MAPK and the nuclear translocation of NF-κB p50/p65, increased the protein levels of inhibitor kappa B-α. Furthermore, our study shows that the LPS-induced release of inflammatory mediators was suppressed by SB203580, pyrrolidine dithiocarbamate, and small interfering RNA.

CONCLUSIONS

Prophylactic treatment with lidocaine inhibits LPS-induced release of inflammatory mediators from microglia, and these effects may be mediated by blockade of p38 MAPK and NF-κB signaling pathways.

Palmitate induces interleukin-8 expression in human aortic vascular smooth muscle cells via Toll-like receptor 4/nuclear factor-κB pathway (TLR4/NF-κB-8)

BACKGROUND

Recent evidence demonstrates that saturated free fatty acids (FFAs) induce the inflammatory response via the Toll-like receptor 4 (TLR4) pathway. Interleukin-8 (IL-8) is a proinflammatory cytokine that induces vascular smooth muscle cell proliferation and migration in vitro. However, the regulation of IL-8 expression by palmitate in human vascular smooth muscle cells (HVSMCs) has not been clarified. The aim of this study was to investigate the regulation of IL-8 expression by free fatty acids and determine the underlying mechanisms in HVSMCs.

METHODS

Human vascular smooth muscle cells were cultured and treated with palmitate, various signaling inhibitors or TLR4 shRNA adenovirus, and the mRNA and protein expression levels of IL-8, nuclear factor κB (NF-κB) luciferase activity and NF-κB p65 binding activity were studied.

RESULTS

Palmitate induced IL-8 mRNA expression and secretion in a dose-dependent manner. Palmitate significantly stimulated both nuclear factor κB (NF-κB) luciferase activity and NF-κB p65 binding activity, which were markedly diminished by pretreatment with the NF-κB inhibitor, parthenolide. Parthenolide pretreatment also abolished IL-8 mRNA and protein induction by palmitate. By contrast, disrupting the ceramide and phosphoinositide-3 kinase (PI3K) pathways with myriocin and wortmannin did not affect palmitate-induced IL-8 expression. Inhibition of protein kinase C (PKC) activation with calphostin C and chelerythrine partially suppressed palmitate-stimulated IL-8 expression, but it had no effect on palmitate-induced NF-κB activation. Finally, knockdown of TLR4 markedly abolished palmitate-induced NF-κB activation and IL-8 expression.

CONCLUSIONS

Palmitate induces IL-8 gene expression in HVSMCs through the TLR4/NF-κB pathway.

Multifunctional regulation of angiogenesis by high-density lipoproteins

AIMS

High-density lipoproteins (HDL) exert striking anti-inflammatory effects and emerging evidence suggests that they may augment ischaemia-mediated neovascularization. We sought to determine whether HDL conditionally regulates angiogenesis, depending on the pathophysiological context by (i) inhibiting inflammation-induced angiogenesis, but also; (ii) enhancing ischaemia-mediated angiogenesis.

METHODS AND RESULTS

Intravenously delivered apolipoprotein (apo) A-I attenuated neovascularization in the murine femoral collar model of inflammation-induced angiogenesis, compared with phosphate-buffered saline infused C57BL6/J mice (58%), P < 0.05. Conversely, apoA-I delivery augmented neovessel formation (75%) and enhanced blood perfusion (45%) in the murine hindlimb ischaemia model, P < 0.05. Reconstituted HDL (rHDL) was tested on key angiogenic cell functions in vitro. rHDL inhibited human coronary artery endothelial cell migration (37.9 and 76.9%), proliferation (15.7 and 40.4%), and tubulogenesis on matrigel (52 and 98.7%) when exposed to two inflammatory stimuli: tumour necrosis factor-α (TNF-α) and macrophage-conditioned media (MCM). In contrast, rHDL significantly augmented hypoxia-stimulated migration (36.9%), proliferation (135%), and tubulogenesis (22.9%), P < 0.05. Western blot and RT-PCR analyses revealed that these divergent actions of rHDL were associated with conditional regulation of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and VEGF receptor 2, which were attenuated in response to TNF-α (40.4, 41.0, and 33.2%) and MCM (72.5, 30.7, and 69.5%), but augmented by rHDL in hypoxia (39.8, 152.6, and 15.7%%), all P < 0.05.

CONCLUSION

HDL differentially regulates angiogenesis dependent upon the pathophysiological setting, characterized by suppression of inflammation-associated angiogenesis, and conversely, by the enhancement of hypoxia-mediated angiogenesis. This has significant implications for therapeutic modulation of neovascularization.

Purpurogallin exerts anti‑inflammatory effects in lipopolysaccharide‑stimulated BV2 microglial cells through the inactivation of the NF‑κB and MAPK signaling pathways

In this study, we investigated the inhibitory effects of purpurogallin, a naturally occurring phenol, on the production of lipopolysaccharide (LPS)-induced pro-inflammatory mediators and cytokines in BV2 microglia cells. The cells were pre-treated or not with various concentrations of purpurogallin and then stimulated with 0.5 µg/ml LPS. Cell viability was measured by MTT assay. We also measured the production of nictric oxice (NO) and prostaglandin E2 (PGE2). Our data indicated that treatment with purpurogallin significantly inhibited the excessive production of NO and PGE2 in LPS-stimulated BV2 microglial cells. These inhibitory effects were associated with the downregulation of key enzymes for NO and PGE2, inducible NO synthase (iNOS) and cyclooxygenase-2 (COX2) expression, respectively. Purpurogallin also attenuated the production of pro-inflammatory cytokines, including interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) by suppressing their mRNA and protein expression. The molecular mechanisms underlying the purpurogallin-mediated attenuation of inflammation in BV2 cells closely correlated with the suppression of the translocation of the nuclear factor-κB (NF-κB) p65 subunit into the nucleus and the degradation of the inhibitor of NF-κB (IκB). Moreover, purpurogallin exhibited anti-inflammatory properties by suppressing the phosphatidylinositol 3-kinase/Akt and mitogen-activated protein kinase signaling pathways. These findings suggest that purpurogallin exerts neuroprotective effects through the suppression of pro-inflammatory pathways in activated microglia.

Lipid peroxidation and inflammatory molecules as markers of coronary artery disease

Oxidized low density lipoproteins (oxLDLs) may exert several pro-inflammatory effects that can contribute to the development of coronary artery disease (CAD). Evaluating a possible correlation between oxLDLs and clinical expression of CAD, we measured specific lipid peroxidation indices in healthy subjects and in patients at different clinical stages of CAD. We observed a slight, but not significant, increase in plasma content of cholesterol oxidation products, i.e. oxysterols, in all CAD patients, and a slight, but not significant, increase of 4-hydroxynonenal-protein adducts only in subjects with acute CAD. Moreover, CAD patients showed a plasma rise of specific inflammatory proteins, i.e. C-reactive protein, intercellular adhesion molecule-1, and interleukin-8, but not of monocyte chemotactic protein-1. These preliminary data, without excluding an involvement of oxidative stress and inflammation in CAD, do not show a strict correlation between relevant plasma markers, other than C-reactive protein, and acute phase of the disease.

Characterization of Khorasan wheat (Kamut) and impact of a replacement diet on cardiovascular risk factors: cross-over dietary intervention study

Background/Objectives:

Khorasan wheat (Kamut) is an ancient grain with widely acclaimed beneficial effects on human health. The objective was to characterise Kamut and to examine the effect of a replacement diet with their products on cardiovascular risk parameters.

Subjects/Methods:

We conducted a randomized, single-blinded cross-over trial with two intervention phases on 22 healthy subjects (14 females; 8 males). The participants were assigned to consume products (bread, pasta and crackers) made either from Kamut or control semi-whole-grain wheat for 8 weeks in a random order. An 8-week washout period was implemented between the interventions. Laboratory analyses were performed both at the beginning and at the end of each intervention phase.

Results:

At a general linear model for repeated measurements adjusted for several confounders, consumption of Kamut products showed a significant reduction of metabolic risk factors such as total cholesterol (mean reduction: −8.46 mg/dl; −4%), low-density lipoprotein cholesterol (−9.82 mg/dl; −7.8%) and blood glucose. Similarly, redox status was significantly improved only after the Kamut intervention phase, as measured by a reduction in both thiobarbituric acid reactive substances (−0.17 nmol/ml; −21.5%) and carbonyl levels (−0.16 nmol/ml; −17.6%). The replacement diet with Kamut products also resulted in a significant increase of serum potassium and magnesium. Circulating levels of key pro-inflammatory cytokines (interleukin (IL)-6, IL-12, tumour necrosis factor-α and vascular endothelial growth factor) were significantly reduced after the consumption of Kamut products.

Conclusions:

The present results suggest that a replacement diet with Kamut products could be effective in reducing metabolic risk factors, markers of both oxidative stress and inflammatory status.

The role of statins in prevention and treatment of community acquired pneumonia: a systematic review and meta-analysis

BACKGROUND

Emerging epidemiological evidence suggests that statins may reduce the risk of community-acquired pneumonia (CAP) and its complications.

PURPOSE

Performed a systematic review to address the role of statins in the prevention or treatment of CAP.

DATA SOURCE

Ovid MEDLINE, Cochrane, EMBASE, ISI Web of Science, and Scopus from inception through December 2011 were searched for randomized clinical trials, cohort and case-control studies.

STUDY SELECTION

Two authors independently reviewed studies that examined the role of statins in CAP.

DATA EXTRACTION

Data about study characteristics, adjusted effect-estimates and quality characteristics was extracted.

DATA SYNTHESIS

Eighteen studies corresponding to 21 effect-estimates (eight and 13 of which addressed the preventive and therapeutic roles of statins, respectively) were included. All studies were of good methodological quality. Random-effects meta-analyses of adjusted effect-estimates were used. Statins were associated with a lower risk of CAP, 0.84 (95% CI, 0.74-0.95), I(2) = 90.5% and a lower short-term mortality in patients with CAP, 0.68 (95% CI, 0.59-0.78), I(2) = 75.7%. Meta-regression did not identify sources of heterogeneity. A funnel plot suggested publication bias in the treatment group, which was adjusted by a novel regression method with a resultant effect-estimate of 0.85 (95% CI, 0.77-0.93). Sensitivity analyses using the rule-out approach showed that it is unlikely that the results were due to an unmeasured confounder.

CONCLUSIONS

Our meta-analysis reveals a beneficial role of statins for the risk of development and mortality associated with CAP. However, the results constitute very low quality evidence as per the GRADE framework due to observational study design, heterogeneity and publication bias.

Analysis of systemic endothelin-1, matrix metalloproteinase-9, macrophage chemoattractant protein-1, and high-sensitivity C-reactive protein in normal-tension glaucoma

PURPOSE

To investigate the roles of vascular dysregulation and inflammation in normal-tension glaucoma (NTG), we determined the plasma levels of endothelin-1 (ET-1), matrix metalloproteinase-9 (MMP-9), macrophage chemoattractant protein-1 (MCP-1), and high-sensitivity C-reactive protein (hs-CRP).

MATERIALS AND METHODS

Forty-five patients with NTG and age-matched 35 healthy controls were enrolled in this study. Blood samples from all subjects were assayed for ET-1, MMP-9, MCP-1, and hs-CRP concentrations and other systemic factors.

RESULTS

There were no significant differences in hemoglobin, hematocrit, RBC count, WBC count, platelet count, fasting glucose, HbA1c, total cholesterol, triglyceride, LDL, and HDL between the NTG and control groups. The systemic levels of ET-1 and MCP-1 were significantly higher in the NTG group than in the control group (p = 0.05 and 0.02, respectively). The MMP-9 and hs-CRP levels were not significantly different between the NTG and control groups.

CONCLUSIONS

After excluding patients with cardiovascular and other systemic diseases, plasma ET-1 and MCP-1 levels were elevated in patients with NTG. The MMP-9 and hs-CRP levels were not significantly different in NTG. Increased ET-1 and MCP-1 levels suggest that ischemia/inflammation may play a role in the pathogenesis of NTG.

Why sex matters: the biological mechanisms of cardiovascular disease

Cardiovascular disease (CVD) is the leading determinant of mortality and morbidity in women. However, a full understanding of the basic and clinical aspects of CVD in women is far from being accomplished. Sexual dimorphism in CVD has been reported both in humans and experimental animals. Menopause is a risk factor for CVD due to the reduction of endogenous estrogen, although the mechanisms underlying are poorly understood. Estrogens act through binding to vascular estrogen receptors and by non-genomic mechanisms. Advances in this field are essential to improve CVD diagnostic and clinical strategies in women, and to develop sex-specific prevention plans as much as female-oriented treatment algorithms. This paper reviews pathophysiology of CVD in women and its potential clinical implications. Particular emphasis is given to biochemical markers and to indicators of cardiovascular dysfunction and damage. Estimation of these parameters, central to cardiovascular pathophysiology, could represent a particularly relevant tool in female patients. More research is needed to identify women who will profit most of early intervention.