MCP1 Inverts the Correlation between FGF23 and Omega 6/3 Ratio: Is It Also True in Renal Transplantation?

During chronic kidney disease (CKD) progression, an increase in fibroblast growth factor (FGF23) is present. In stage 5, a positive correlation between FGF23 and omega-6 (n-6) polyunsaturated fatty acids (PUFAs) emerges. Hypothesizing that the rising positive correlation between monocyte chemoattractant protein 1 (MCP1) and n-6 in stage 4 could be the cause, we previously explored FGF23 and MCP1's roles in dyslipidemia and cardiovascular risk in CKD. In the present paper, we retraced the study evaluating 40 kidney transplant patients (KTx), a cohort where several factors might modify the previous relationships found. An ELISA and gas chromatography assessed the MCP1, FGF23, and PUFA levels. Despite the FGF23 increase (p < 0.0001), low MCP1 levels were found. A decrease in the n-6/n-3 ratio (p = 0.042 CKD stage 4 vs. 5) lowered by the increase in both n-3 αlinolenic (p = 0.012) and docosapentaenoic acid (p = 0.049) was observed. A negative correlation between FGF23 and the n-6/n-3 ratio in CKD stage 4 (r2 -0.3 p = 0.043) and none with MCP1 appeared. According to our findings, different mechanisms in the relationship between FGF23, PUFAs, and MCP1 in CKD and KTx patients might be present, which is possibly related to the immunosuppressive status of the last. Future research will further clarify our hypothesis.

Effect of Anti-Inflammatory and Antimicrobial Cosupplementations on Sepsis Prevention in Critically Ill Trauma Patients at High Risk for Sepsis

Background: Sepsis development in patients with trauma is associated with bad prognosis. This study investigated the effect of immunomodulatory interventions in major trauma patients at high risk for sepsis. Methods: In a randomized, double-blinded, controlled design, severe trauma patients were stratified by leukocyte anti-sedimentation rate (LAR) test into high risk (HR) and low risk (LR) for sepsis. The HR patients were randomly allocated into intravenous vitamin C plus vitamin B1 (HR-CB), intramuscular vitamin D plus oral Lactobacillus probiotics (HR-DP), or control (HR-C) groups. The clinical trial was registered at clinicaltrials.gov (https://clinicaltrials.gov/show/NCT04216459). Outcomes: The primary outcome was Acute Physiologic Assessment and Chronic Health Evaluation score II (APACHE II) score. Secondary outcomes included sepsis incidence, changes in Sequential Organ Failure Assessment (SOFA) score, and serum monocyte chemoattractant protein-1 (MCP-1) on day 6 from baseline, 28-day mortality, intensive care unit (ICU), and hospital discharge. Results: The HR-DP, HR-CB, and LR groups showed a significantly lower incidence of sepsis development (20%, 20%, and 16%, respectively, versus 60% in the HR-C group, p-value = 0.004). The three groups also showed a significant improvement in APACHE II and SOFA scores. Besides, MCP-1 levels were significantly decreased in HR-DP and HR-CB groups compared to the HR-C group (p-value ≤ 0.05). Significantly decreased mortality (10% and 16% versus 60% in the HR-C group) and increased ICU discharge (95% and 84% versus 45% in the HR-C group) were observed in HR-CB and LR groups (p-value = 0.001). Conclusion: Both combinations of interventions improved APACHE II scores and reduced sepsis incidence in trauma patients. The LAR combined with injury severity score were good sepsis predictors.

M2 macrophage accumulation contributes to pulmonary fibrosis, vascular dilatation, and hypoxemia in rat hepatopulmonary syndrome

Hepatopulmonary syndrome (HPS) markedly increases the mortality of patients. However, its pathogenesis remains incompletely understood. Rat HPS develops in common bile duct ligation (CBDL)-induced, but not thioacetamide (TAA)-induced cirrhosis. We investigated the mechanisms of HPS by comparing these two models. Pulmonary histology, blood gas exchange, and the related signals regulating macrophage accumulation were assessed in CBDL and TAA rats. Anti-polymorphonuclear leukocyte (antiPMN) and anti-granulocyte-macrophage colony stimulating factor (antiGM-CSF) antibodies, clodronate liposomes (CL), and monocyte chemoattractant protein 1 (MCP1) inhibitor (bindarit) were administrated in CBDL rats, GM-CSF, and MCP1 were administrated in bone marrow-derived macrophages (BMDMs). Pulmonary inflammatory cell recruitment, vascular dilatation, and hypoxemia were progressively developed by 1 week after CBDL, but only occurred at 4 week after TAA. Neutrophils were the primary inflammatory cells within 3 weeks after CBDL and at 4 week after TAA. M2 macrophages were the primary inflammatory cells, meantime, pulmonary fibrosis, GM-CSFR, and CCR2 were specifically increased from 4 week after CBDL. AntiPMN antibody treatment decreased neutrophil and macrophage accumulation, CL or the combination of antiGM-CSF antibody and bindarit treatment decreased macrophage recruitment, resulting in pulmonary fibrosis, vascular dilatation, and hypoxemia in CBDL rats alleviated. The combination treatment of GM-CSF and MCP1 promoted cell migration, M2 macrophage differentiation, and transforming growth factor-β1 (TGF-β1) production in BMDMs. Conclusively, our results highlight neutrophil recruitment mediates pulmonary vascular dilatation and hypoxemia in the early stage of rat HPS. Further, M2 macrophage accumulation induced by GM-CSF/GM-CSFR and MCP1/CCR2 leads to pulmonary fibrosis and promotes vascular dilatation and hypoxemia, as a result, HPS develops.

C-C motif chemokine receptor 2 as a novel intermediate in the ovulatory cascade

Expression of immune function genes within follicle cells has been reported in ovaries from many species. Recent work from our laboratory showed a direct effect of the monocyte chemoattractant protein 1/C-C motif chemokine receptor 2 system within the feline cumulus oocyte complex, by increasing the mRNA levels of key genes involved in the ovulatory cascade in vitro. Studies were designed to evaluate if C-C motif chemokine receptor 2 acts as a novel mediator of the ovulatory cascade in vitro. Therefore, feline cumulus oocyte complexes were cultured in the presence or absence of a highly selective C-C motif chemokine receptor 2 antagonist together with known inducers of cumulus-oocyte expansion and/or oocyte maturation to assess mRNA expression of key genes related to periovulatory events in other species as well as oocyte maturation. Also, the effects of recombinant monocyte chemoattractant protein 1 on spontaneous or gonadotrophin-induced oocyte maturation were assessed. This is an in vitro system using isolated cumulus oocyte complexes from feline ovaries. The present study reveals the modulation of several key ovulatory genes by a highly selective C-C motif chemokine receptor 2 antagonist. However, this antagonist was not enough to block the oocyte maturation induced by gonadotropins or amphiregulin. Nonetheless, recombinant monocyte chemoattractant protein 1 had a significant effect on spontaneous oocyte maturation, increasing the percentage of metaphase II stage oocytes in comparison to the control. This is the first study in any species to establish C-C motif chemokine receptor 2 as a mediator of some actions of the mid-cycle gonadotrophin surge.

Host engulfment pathway controls inflammation in inflammatory bowel disease

Chronic diseases, including inflammatory bowel disease (IBD) urgently need new biomarkers as a significant proportion of patients, do not respond to current medications. Inflammation is a common factor in these diseases, and microbial sensing in the intestinal tract is critical to initiate the inflammation. We have identified ELMO1 (engulfment and cell motility protein 1) as a microbial sensor in epithelial and phagocytic cells that turns on inflammatory signals. Using a stem cell-based 'gut-in-a-dish' coculture model, we studied the interactions between microbes, epithelium, and monocytes in the context of IBD. To mimic the in vivo cell physiology, enteroid-derived monolayers (EDMs) were generated from the organoids isolated from WT and ELMO1-/- mice and colonic biopsies of IBD patients. The EDMs were infected with the IBD-associated microbes to monitor the inflammatory responses. ELMO1-depleted EDMs displayed a significant reduction in bacterial internalization, a decrease in pro-inflammatory cytokine productions and monocyte recruitment. The expression of ELMO1 is elevated in the colonic epithelium and in the inflammatory infiltrates within the lamina propria of IBD patients where the higher expression is positively correlated with the elevated expression of pro-inflammatory cytokines, MCP-1 and TNF-α. MCP-1 is released from the epithelium and recruits monocytes to the site of inflammation. Once recruited, monocytes require ELMO1 to engulf the bacteria and propagate a robust TNF-α storm. These findings highlight that the dysregulated epithelial ELMO1 → MCP-1 axis can serve as an early biomarker in the diagnostics of IBD and other inflammatory disorders.

Oxidative stress, inflammation and disease activity biomarkers in lupus nephropathy

Lupus nephropathy is a severe and frequent complication of systemic lupus erythematosus. Here, we assessed the biomarkers of oxidative stress, inflammation and disease activity in patients with lupus nephritis. Thirty-four patients with active lupus nephritis, 31 patients with inactive lupus nephritis and 20 lupus patients without renal damage (non-lupus nephritis) were studied. Oxidative stress biomarkers malonyldialdehyde, oxidized-to-total glutathione, catalase, superoxide dismutase and total antioxidant status were assessed, as well as inflammation biomarkers CRP, interleukin 6 and monocyte chemoattractant protein 1. Renal tubular disease biomarkers neutrophil gelatinase-associated lipocalin and β2-microglobulin were assessed, together with the classic disease activity biomarkers urinary protein/creatinine ratio, anti-dsDNA, anti-C1q antibody and complement proteins C3 and C4. Significant differences were found between active lupus nephritis and inactive lupus nephritis patients and between active lupus nephritis and non-lupus nephritis patients for all the assessed biomarkers (P < 0.05), except for catalase, superoxide dismutase and interleukin 6. There is an imbalance in the redox status in active lupus nephritis patients that would be involved in lipid peroxidation of the glomerular basal membrane that would alter its integrity and could also affect renal tubular function in these patients.

NFAT5 promotes arteriogenesis via MCP-1-dependent monocyte recruitment

Studies have demonstrated that nuclear factor of activated T cells 5 (NFAT5) is not only a tonicity‐responsive transcription factor but also activated by other stimuli, so we aim to investigate whether NFAT5 participates in collateral arteries formation in rats. We performed femoral artery ligature (FAL) in rats for hindlimb ischaemia model and found that NFAT5 was up‐regulated in rat adductors with FAL compared with sham group. Knockdown of NFAT5 with locally injection of adenovirus‐mediated NFAT5‐shRNA in rats significantly inhibited hindlimb blood perfusion recovery and arteriogenesis. Moreover, NFAT5 knockdown decreased macrophages infiltration and monocyte chemotactic protein‐1 (MCP‐1) expression in rats adductors. In vitro, with interleukin‐1β (IL‐1β) stimulation and loss‐of‐function studies, we demonstrated that NFAT5 knockdown inhibits MCP‐1 expression in endothelial cells and chemotaxis of THP‐1 cells regulated by ERK1/2 pathway. More importantly, exogenous MCP‐1 delivery could recover hindlimb blood perfusion, promote arteriogenesis and macrophages infiltration in rats after FAL, which were depressed by NFAT5 knockdown. Besides, NFAT5 knockdown also inhibited angiogenesis in gastrocnemius muscles in rats. Our results indicate that NFAT5 is a critical regulator of arteriogenesis and angiogenesis via MCP‐1‐dependent monocyte recruitment, suggesting that NFAT5 may represent an alternative therapeutic target for ischaemic diseases.

The INTUIT Study: Investigating Neuroinflammation Underlying Postoperative Cognitive Dysfunction

BACKGROUND/OBJECTIVES

Every year, up to 40% of the more than 16 million older Americans who undergo anesthesia/surgery develop postoperative cognitive dysfunction (POCD) or delirium. Each of these distinct syndromes is associated with decreased quality of life, increased mortality, and a possible increased risk of Alzheimer's disease. One pathologic process hypothesized to underlie both delirium and POCD is neuroinflammation. The INTUIT study described here will determine the extent to which postoperative increases in cerebrospinal fluid (CSF) monocyte chemoattractant protein 1 (MCP-1) levels and monocyte numbers are associated with delirium and/or POCD and their underlying brain connectivity changes.

DESIGN

Observational prospective cohort.

SETTING

Duke University Medical Center, Duke Regional Hospital, and Duke Raleigh Hospital.

PARTICIPANTS

Patients 60 years of age or older (N = 200) undergoing noncardiac/nonneurologic surgery.

MEASUREMENTS

Participants will undergo cognitive testing before, 6 weeks, and 1 year after surgery. Delirium screening will be performed on postoperative days 1 to 5. Blood and CSF samples are obtained before surgery, and 24 hours, 6 weeks, and 1 year after surgery. CSF MCP-1 levels are measured by enzyme-linked immunosorbent assay, and CSF monocytes are assessed by flow cytometry. Half the patients will also undergo pre- and postoperative functional magnetic resonance imaging scans. 32-channel intraoperative electroencephalogram (EEG) recordings will be performed to identify intraoperative EEG correlates of neuroinflammation and/or postoperative cognitive resilience. Eighty patients will also undergo home sleep apnea testing to determine the relationships between sleep apnea severity, neuroinflammation, and impaired postoperative cognition. Additional assessments will help evaluate relationships between delirium, POCD, and other geriatric syndromes.

CONCLUSION

INTUIT will use a transdisciplinary approach to study the role of neuroinflammation in postoperative delirium and cognitive dysfunction and their associated functional brain connectivity changes, and it may identify novel targets for treating and/or preventing delirium and POCD and their sequelae. J Am Geriatr Soc 67:794-798, 2019.

TAK-442, a Direct Factor Xa Inhibitor, Inhibits Monocyte Chemoattractant Protein 1 Production in Endothelial Cells via Involvement of Protease-Activated Receptor 1

Oral blood coagulation inhibitors and their receptors, such as factor Xa (FXa), thrombin, and the thrombin receptor protease-activated receptor 1 (PAR1), are entered into clinical trials for acute coronary syndrome therapy; however, the results obtained so far are different for each drug. The underlying mechanisms of the results have not been fully investigated. We studied the in vitro anti-inflammatory effects of the selective FXa inhibitor TAK-442 on human endothelial cells, with comparing those of the selective thrombin inhibitor melagatran and the PAR1 antagonist vorapaxar. In human umbilical vein endothelial cells, FXa-increased production of monocyte chemoattractant protein 1 (MCP-1), a key inflammatory mediator, was inhibited by TAK-442 but not melagatran, and was also remarkably suppressed by vorapaxar. As thrombin did, FXa increased calcium mobilization in PAR1-overexpressed Chinese hamster ovary cells, which was selectively inhibited by TAK-442 and vorapaxar. We therefore confirmed the inhibitory effect of TAK-442 in endothelial MCP-1 production and the PAR1 intervention in the response. Our results suggest that TAK-442 may have anti-inflammatory potential in addition to its anti-thrombotic effects.

Analysis of urinary macrophage migration inhibitory factor in systemic lupus erythematosus

Objective

To characterise the clinical relevance of urinary macrophage migration inhibitory factor (uMIF) concentrations in patients with systemic lupus erythematosus (SLE).

Methods

MIF, adjusted for urine creatinine, was quantified by ELISA in urine samples from 64 prospectively recruited patients with SLE. Serum MIF and urinary monocyte chemoattractant protein 1 (uMCP-1) were quantified by ELISA in a subset of patients (n = 39). Disease activity was assessed using the SLE Disease Activity Index-2000 (SLEDAI-2K) score.

Results

uMIF was detectable in all patients with SLE. uMIF was positively correlated with overall SLEDAI-2K, was significantly higher in patients with SLE with high disease activity (SLEDAI-2K≥10) compared with those with inactive disease (SLEDAI-2K<4), and this association remained significant after adjusting for ethnicity, flare and use of immunosuppressants. uMIF was also significantly higher in SLE patients with flare of disease, although not confirmed in multivariable analysis. No significant differences in uMIF levels were observed according to the presence of renal disease activity, as assessed by renal SLEDAI-2K or biopsy-confirmed lupus nephritis. In contrast, uMCP-1 was significantly higher in SLE patients with active renal disease. uMIF expression was not associated with irreversible organ damage accrual or glucocorticoid use.

Conclusions

These data suggest uMIF as a potential overall but not renal-specific SLE biomarker, whereas uMCP-1 is a renal-specific SLE biomarker.

Early plasma monocyte chemoattractant protein 1 predicts the development of sepsis in trauma patients: A prospective observational study

Monocyte chemoattractant protein 1 (MCP-1) is an initiating cytokine of the inflammatory cascade. Extracellular MCP-1 exhibits pro-inflammatory characteristic and plays a central pathogenic role in critical illness. The purpose of the study was to identify the association between plasma MCP-1 levels and the development of sepsis after severe trauma.The plasma levels of MCP-1 in severe trauma patients were measured by a quantitative enzyme-linked immune sorbent assay and the dynamic release patterns were recorded at three time points during seven days post-trauma. The related factors of prognosis were compared between sepsis and non-sepsis groups and analyzed using multivariate logistic regression analysis. We also used receiver operating characteristic (ROC) curves to assess the values of different variables in predicting sepsis.A total of 72 patients who met criteria indicative of severe trauma (72.22% of male; mean age, 49.40 ± 14.29 years) were enrolled. Plasma MCP-1 concentrations significantly increased on post-trauma day 1 and that this increase was significantly correlated with the Injury Severity Score (ISS) and interleukin-6 (IL-6). Multivariate logistic regression analysis showed that early MCP-1, ISS, and IL-6 were independent risk factors for sepsis in severe trauma patients. Incorporation of the early MCP-1 into the ISS can increase the discriminative performance for predicting development of sepsis.Early plasma MCP-1 concentrations can be used to assess the severity of trauma and is correlated with the development of sepsis after severe trauma. The addition of the early MCP-1 levels to the ISS significantly improves its ability to predict development of sepsis.

Monocyte chemoattractant protein 1 expression and proliferation in primary central nervous system lymphoma

Whether the poor prognosis of primary central nervous system lymphoma (PCNSL) compared with systemic diffuse large B cell lymphoma (DLBCL) is attributable to the immune privilege of the intracerebral location or to intrinsic differences in the biological characteristics of two types of lymphoma remains unclear. Monocyte chemoattractant protein 1 (MCP-1) is essential to support tumor cell survival and growth, and the present study aimed to compare MCP-1 expression in PCNSL and peripheral DLBCL. The present study included 19 patients with PCNSL and 16 patients with DLBCL, all of whom had tissue diagnosis and lymphoma tissue samples available for analysis. Histology included immunohistochemistry using antibodies against a panel of lymphoma markers, antibodies specific to MCP-1, and antibodies specific to tumor-associated macrophages. MCP-1 expression was quantified using immunostaining scoring. RNA extraction and reverse transcription-quantitative polymerase chain reaction were used to determine MCP-1 mRNA expression. In addition, a human brain-derived lymphoma cell line, HKBML, was stimulated with MCP-1 and cell proliferation was measured by 5-bromo-2′-deoxyuridine incorporation. The expression levels of MCP-1 mRNA and MCP-1 protein were significantly increased in PCNSL compared with peripheral DLBCL. MCP-1 induced tyrosine phosphorylation of mitogen-activated protein kinase in HKBML cells, as analyzed by western blotting. The results of the present study indicated that MCP-1 expression in PCNSL promoted cell proliferation in an autocrine manner.

CCL2/Monocyte Chemoattractant Protein 1 and Parathyroid Hormone Action on Bone

Chemokines are small molecules that play a crucial role as chemoattractants for several cell types, and their components are associated with host immune responses and repair mechanisms. Chemokines selectively recruit monocytes, neutrophils, and lymphocytes and induce chemotaxis through the activation of G protein-coupled receptors. Two well-described chemokine families (CXC and CC) are known to regulate the localization and trafficking of immune cells in cases of injury, infection, and tumors. Monocyte chemoattractant protein 1 (MCP-1/CCL2) is one of the important chemokines from the CC family that controls migration and infiltration of monocytes/macrophages during inflammation. CCL2 is profoundly expressed in osteoporotic bone and prostate cancer-induced bone resorption. CCL2 also regulates physiological bone remodeling in response to hormonal and mechanical stimuli. Parathyroid hormone (PTH) has multifaceted effects on bone, depending on the mode of administration. Intermittent PTH increases bone in vivo by increasing the number and activity of osteoblasts, whereas a continuous infusion of PTH decreases bone mass by stimulating a net increase in bone resorption. CCL2 is essential for both anabolic and catabolic effects of PTH. In this review, we will discuss the pharmacological role of PTH and involvement of CCL2 in the processes of PTH-mediated bone remodeling.

-2518 A/G MCP-1 but not -403 G/A RANTES gene polymorphism is associated with enhanced risk of basal cell carcinoma

Introduction

Polymorphic variants of MCP-1 and RANTES genes and their protein serum levels have been implicated in the increased risk and severity of several malignancies. However, the subject has not been explored in basal cell carcinoma (BCC) patients so far.

Aim

To investigate the association between monocyte chemoattractant protein 1 (MCP-1) (–2518 A/G) and RANTES (–403 G/A) polymorphism and risk and clinical course of BCC.

Material and methods

The study group consisted of 150 unrelated patients with BCC and 140 healthy, unrelated, age- and sex-matched volunteers. The polymorphisms were analysed using the amplification refractory mutation system polymerase chain reaction method (ARMS-PCR) and single specific primer-polymerase chain reaction (SSP-PCR). Serum cytokine levels were measured with ELISA.

Results

The presence of the MCP-1 –2518 GG genotype was statistically more frequent in BCC patients and it increased the risk of BCC (OR = 2.63, p = 0.003). Genotype –330 GG was statistically more common in patients with less advanced tumours (OR = 2.8, p = 0.017). Monocyte chemoattractant protein 1 serum level was statistically higher with GG genotype. In the BCC group MCP-1 serum levels were decreased. Neither polymorphic variants of RANTES nor the chemokine serum concentration differed significantly between the study groups.

Conclusions

These findings suggest that –2518 A/G MCP-1 polymorphism may be involved in BCC pathogenesis.

Hyperglycaemia, oxidative stress and inflammatory markers

INTRODUCTION

The increasing prevalence of hyperglycaemia implicates a state of oxidative stress and inflammation. Traditional and emerging biomarkers associated with increasing hyperglycaemia were assessed to clarify their role they play in hyperglycaemia.

RESULTS

309 participants attending a rural diabetic screening program were categorised into control and quintile groups based upon glucose levels: 1st quintile - <4.5 mmol/L and 4th, 5th quintile - >6.1 mmol/L. Significant results were obtained for anthropometric data and biochemical markers - glucose, HbA1c and total cholesterol (P < 0.001); oxidative stress: glutathione (P < 0.001), glutathione:glutathione disulfide and 8-hydroxy-2-deoxyguanosine (P < 0.05). Interleukin -1β and inflammatory marker ratios IL-6/IL-10, IL-1β/IL-10, MCP-1/IL-10, IGF-1/IL-10 and IL-6/IL-1β were significant (P < 0.05).

CONCLUSION

This study provided further evidence that inflammatory and oxidative stress biomarkers may contribute to diagnostic information associated with preclinical increases in BGL. Further we have provided a unique study in the analysis of ratios of inflammatory biomarkers and correlations with increasing BGL.

Platelet CD40 contributes to enhanced monocyte chemoattractant protein 1 levels in patients with resistant hypertension

BACKGROUND

Growing evidence shows that inflammation plays a pivotal role in the pathophysiology of essential hypertension (EH). Although it is acknowledged that target organ damage involves an inflammatory response, most work has focused on the role of macrophages. However, recently, platelets were identified as inducing inflammation partly by releasing cytokines. The goal of our study was to evaluate the role of platelets as inflammatory cells in the pathogenesis of EH.

METHODS

Thirty-nine patients with EH and 30 healthy normotensive controls have been examined. Expression of platelet CD40 was measured by flow cytometry. Serum levels of monocyte chemoattractant protein 1 (MCP-1) and sCD40L were measured via a multiplexing assay. In in vitro experiments, activated platelets were cocultured with human umbilical vein endothelial cells (HUVEC) in the presence and absence of anti-CD154 antibodies. MCP-1 in the supernatants was measured by EIA.

RESULTS

Essential hypertension patients showed significantly enhanced MCP-1 levels with highest levels in EH patients with microalbuminuria. EH patients showed increased expression of platelet CD40. In the cell coculture model, activated platelets were able to significantly induce MCP-1 release from HUVEC in a CD40L-dependent manner. EH patients showed elevated sCD40L levels with a positive correlation with MCP-1 levels.

CONCLUSIONS

Platelets can contribute to enhanced MCP-1 levels in EH. MCP-1 is markedly elevated in serum of EH patients with highest levels in patients with microalbuminuria, one early sign of renal target organ damage. Further studies are required to test whether MCP-1 blocking or antiplatelet strategies may represent new therapeutic options in preventing hypertensive target organ damage.

Serum and synovial fluid chemokine ligand 2/monocyte chemoattractant protein 1 concentrations correlates with symptomatic severity in patients with knee osteoarthritis

OBJECTIVE

Serum and synovial fluid (SF) chemokine ligand 2 (CCL2)/monocyte chemoattractant protein 1 (MCP-1) concentrations have been identified to be increased in osteoarthritis (OA) patients. The scope of this study was to examine CCL2 concentrations in serum and SF of knee OA patients and to explore their association with patient-reported symptomatic severity.

METHOD

One hundred and sixty-one knee OA patients and 138 healthy controls were enrolled into the study from our hospital. We collected Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores from OA patients and measured CCL2 concentrations in serum and SF using enzyme-linked immunosorbent assay method, and correlation between WOMAC scores and CCL2 concentrations were analysed.

RESULTS

CCL2 concentrations in SF instead of serum were independently and positively associated with self-reported greater pain (r = 0.460, P < 0.001) and physical disability (r = 0.561, P < 0.001) in OA patients.

CONCLUSION

CCL2 in SF might serve as a novel and reliable biomarker for assessing symptomatic severity of OA.

Aortic cholesterol accumulation correlates with systemic inflammation but not hepatic and gonadal adipose tissue inflammation in low-density lipoprotein receptor null mice

Inflammation is a major contributor to the development of atherosclerotic plaque, yet the involvement of liver and visceral adipose tissue inflammatory status in atherosclerotic lesion development has yet to be fully elucidated. We hypothesized that an atherogenic diet would increase inflammatory response and lipid accumulation in the liver and gonadal adipose tissue (GAT) and would correlate with systemic inflammation and aortic lesion formation in low-density lipoprotein (LDL) receptor null (LDLr-/-) mice. For 32 weeks, LDLr-/- mice (n = 10/group) were fed either an atherogenic (high saturated fat and cholesterol) or control (low fat and cholesterol) diet. Hepatic and GAT lipid content and expression of inflammatory factors were measured using standard procedures. Compared with the control diet, the atherogenic diet significantly increased hepatic triglyceride and total cholesterol (TC), primarily esterified cholesterol, and GAT triglyceride content. These changes were accompanied by increased expression of acyl-CoA synthetase long-chain family member 5, CD36, ATP-binding cassette, subfamily A, member 1 and scavenger receptor B class 1, and they decreased the expression of cytochrome P450, family 7 and subfamily a, polypeptide 1 in GAT. Aortic TC content was positively associated with hepatic TC, triglyceride, and GAT triglyceride contents as well as plasma interleukin 6 and monocyte chemoattractant protein-1 concentrations. Although when compared with the control diet, the atherogenic diet increased hepatic tumor necrosis factor α production, they were not associated with aortic TC content. These data suggest that the LDLr-/- mice responded to the atherogenic diet by increasing lipid accumulation in the liver and GAT, which may have increased inflammatory response. Aortic TC content was positively associated with systemic inflammation but not hepatic and GAT inflammatory status.

Mechanisms of obesity-induced gastrointestinal neoplasia

Obesity is among the fastest growing diseases worldwide; treatment is inadequate, and associated disorders, including gastrointestinal cancers, have high morbidity and mortality. An increased understanding of the mechanisms of obesity-induced carcinogenesis is required to develop methods to prevent or treat these cancers. In this report, we review the mechanisms of obesity-associated colorectal, esophageal, gastric, and pancreatic cancers and potential treatment strategies.

Mast cells protect from post-traumatic spinal cord damage in mice by degrading inflammation-associated cytokines via mouse mast cell protease 4

Mast cells (MCs) are found abundantly in the central nervous system and play a complex role in neuroinflammatory diseases such as multiple sclerosis and stroke. In the present study, we show that MC-deficient Kit(W-sh/W-sh) mice display significantly increased astrogliosis and T cell infiltration as well as significantly reduced functional recovery after spinal cord injury compared to wildtype mice. In addition, MC-deficient mice show significantly increased levels of MCP-1, TNF-α, IL-10 and IL-13 protein levels in the spinal cord. Mice deficient in mouse mast cell protease 4 (mMCP4), an MC-specific chymase, also showed increased MCP-1, IL-6 and IL-13 protein levels in spinal cord samples and a decreased functional outcome after spinal cord injury. A degradation assay using supernatant from MCs derived from either mMCP4(-/-) mice or controls revealed that mMCP4 cleaves MCP-1, IL-6, and IL-13 suggesting a protective role for MC proteases in neuroinflammation. These data show for the first time that MCs may be protective after spinal cord injury and that they may reduce CNS damage by degrading inflammation-associated cytokines via the MC-specific chymase mMCP4.

High-fat diet action on adiposity, inflammation, and insulin sensitivity depends on the control low-fat diet

Animal studies using a high-fat diet (HFD) have studied the effects of lipid overconsumption by comparing a defined HFD either with a natural-ingredient chow diet or with a defined low-fat diet (LFD), despite the dramatic differences between these control diets. We hypothesized that these differences in the control diet could modify the conclusions regarding the effects that an increase of fat in the diet has on several metabolic parameters. For 11 weeks, C57bl6/J mice were fed a low-fat chow diet (8% energy from fat), a typical semisynthetic LFD (12%), or a semisynthetic HFD (sy-HF) (40%). Conclusions about the effect of sy-HF on body weight gain, subcutaneous adipose tissue, insulin sensitivity, and adipose tissue inflammation were modified according to the control LFD. Conversely, conclusions about epididymal and retroperitoneal adipose tissue; fat intake effects on liver and muscular lipids, cholesterol, free fatty acids, and markers of low-grade inflammation; and of adipose tissue macrophage infiltration were the same regardless of the use of low-fat chow diet or semisynthetic LFD. For some physiological outcomes, conflicting conclusions were even reached about the effects of increased fat intake according to the chosen low-fat control. Some deleterious effects of sy-HF may not be explained by lipid overconsumption but rather by the overall quality of ingredients in a semisynthetic diet. According to the control LFD chosen, conclusions on the lipid-related effects of HFDs must be formulated with great care because some end points are profoundly affected by the ingredient composition of the diet rather than by fat content.

Monocyte chemoattractant protein 1-mediated migration of mesenchymal stem cells is a source of intimal hyperplasia

OBJECTIVE

Intimal hyperplasia is considered to be a healing response and is a major cause of vessel narrowing after injury, where migration of vascular progenitor cells contributes to pathological events, including transplant arteriosclerosis.

APPROACH AND RESULTS

In this study, we used a rat aortic-allograft model to identify the predominant cell types associated with transplant arteriosclerosis and to identify factors important in their recruitment into the graft. Transplantation of labeled adventitial tissues allowed us to identify the adventitia as a major source of cells migrating to the intima. RNA microarrays revealed a potential role for monocyte chemoattractant protein 1 (MCP-1), stromal cell-derived factor 1, regulated on activation, normal T cell expressed and secreted, and interferon-inducible protein 10 in the induced vasculopathy. MCP-1 induced migration of adventitial fibroblast cells. CCR2, the receptor for MCP-1, was coexpressed with CD90, CD44, NG2, or sca-1 on mesenchymal stem cells. In vivo experiments using MCP-1-deficient and CCR2-deficient mice confirmed an important role of MCP-1 in the formation of intimal hyperplasia in a mouse model of vascular injury.

CONCLUSIONS

The adventitia is a potentially important cellular source that contributes to intimal hyperplasia, and MCP-1 is a potent chemokine for the recruitment of adventitial vascular progenitor cells to intimal lesions.

Relationships of single nucleotide polymorphisms of monocyte chemoattractant protein 1 and chemokine receptor 2 with susceptibility and clinicopathologic characteristics of neoplasia of uterine cervix in Taiwan women

Few studies reported the implication of single nucleotide polymorphisms (SNPs) of monocyte chemoattractant protein 1 (MCP-1) and its receptor chemokine receptor 2 (CCR-2) in clinical significance of cancer of uterine cervix. We hypothesized that SNPs of MCP-1 and CCR-2 may affect the expression of these genes and then proteins. Therefore, we investigated the influence of the gene polymorphisms of MCP-1 and CCR-2 on the susceptibility and clinicopathologic characteristics of cervical neoplasia in Taiwan women. We recruited 86 patients with invasive cancer and 61 with high-grade dysplasia and 253 control women and selected 1 MCP-1 SNP rs1024611 (-2518G/A) and 1 CCR-2 SNP rs1799864 (190G/A; V64I) to determine their genotypes distribution using polymerase chain reaction-restriction fragment length polymorphism. In comparison to normal individuals with homozygotes GG in MCP-2 SNP, women with GA or AA carried a 2.01 odds ratio of developing cervical cancer. Nevertheless, it was not demonstrated in CCR-2 SNP. Furthermore, women with mutant homozygote (AA) of MCP-1 SNP increased the risk of deep stromal invasion, large tumor diameter, and parametrium invasion of cervical cancer, when compared to those with wild homozygote GG or heterozygote GA. However, women with mutant homozygotes (AA) of CCR-2 SNP did not increase the risk of poor clinicopathologic characteristics. In conclusion, MCP-1 SNP may be correlated with the development, deep stromal invasion, large tumor diameter, and parametrium invasion of cervical cancer but not with cancer recurrence or survival of Taiwan women patients with cancer. However, the SNP of its receptor, CCR-2, is not implicated in cervical cancer.

Chemokine sequestration by viral chemoreceptors as a novel viral escape strategy: withdrawal of chemokines from the environment of cytomegalovirus-infected cells

Human cytomegalovirus (HCMV), a betaherpesvirus, has developed several ways to evade the immune system, notably downregulation of cell surface expression of major histocompatibility complex class I heavy chains. Here we report that HCMV has devised another means to compromise immune surveillance mechanisms. Extracellular accumulation of both constitutively produced monocyte chemoattractant protein (MCP)-1 and tumor necrosis factor-superinduced RANTES (regulated on activation, normal T cell expressed and secreted) was downregulated in HCMV-infected fibroblasts in the absence of transcriptional repression or the expression of polyadenylated RNA for the cellular chemokine receptors CCR-1, CCR-3, and CCR-5. Competitive binding experiments demonstrated that HCMV-infected cells bind RANTES, MCP-1, macrophage inflammatory protein (MIP)-1beta, and MCP-3, but not MCP-2, to the same receptor as does MIP-1alpha, which is not expressed in uninfected cells. HCMV encodes three proteins with homology to CC chemokine receptors: US27, US28, and UL33. Cells infected with HCMV mutants deleted of US28, or both US27 and US28 genes, failed to downregulate extracellular accumulation of either RANTES or MCP-1. In contrast, cells infected with a mutant deleted of US27 continues to bind and downregulate those chemokines. Depletion of chemokines from the culture medium was at least partially due to continuous internalization of extracellular chemokine, since exogenously added, biotinylated RANTES accumulated in HCMV-infected cells. Thus, HCMV can modify the chemokine environment of infected cells through intense sequestering of CC chemokines, mediated principally by expression of the US28-encoded chemokine receptor.

Severe reduction in leukocyte adhesion and monocyte extravasation in mice deficient in CC chemokine receptor 2

CC chemokine receptor 2 (CCR2) is a prominent receptor for the monocyte chemoattractant protein (MCP) group of CC chemokines. Mice generated by gene targeting to lack CCR2 exhibit normal leukocyte rolling but have a pronounced defect in MCP-1-induced leukocyte firm adhesion to microvascular endothelium and reduced leukocyte extravasation. Constitutive macrophage trafficking into the peritoneal cavity was not significantly different between CCR2-deficient and wild-type mice. However, after intraperitoneal thioglycollate injection, the number of peritoneal macrophages in CCR2-deficient mice did not rise above basal levels, whereas in wild-type mice the number of macrophages at 36 h was approximately 3.5 times the basal level. The CCR2-deficient mice showed enhanced early accumulation and delayed clearance of neutrophils and eosinophils. However, by 5 days neutrophils and eosinophils in both CCR2-deficient and wild-type mice had returned to near basal levels, indicating that resolution of this inflammatory response can occur in the absence of macrophage influx and CCR2-mediated activation of the resident peritoneal macrophages. After intravenous injection with yeast beta-glucan, wild-type mice formed numerous large, well-defined granulomas throughout the liver parenchyma, whereas CCR2-deficient mice had much fewer and smaller granulomas. These results demonstrate that CCR2 is a major regulator of induced macrophage trafficking in vivo.