Effect of quercetin glycosides on cognitive functions and cerebral blood flow: a randomized, double-blind, and placebo-controlled study.

OBJECTIVE: This study aimed to examine the effects of quercetin glycoside-containing beverages on cognitive function and cerebral blood flow (CBF) in adult men and women aged between 60 and 75 years. PATIENTS AND METHODS: Eighty healthy men and women with no cognitive impairment and aware of ageing-related forgetfulness underwent a placebo-controlled, randomized, double-blind, and parallel-group trial. They regularly consumed 500 mL of beverage containing 110 mg of quercetin glycoside as isoquercitrin for 40 weeks. Cognitive function assessment by Cognitrax was the endpoint of the study. The participants were assessed for CBF, health-related quality of life, as well as physical, biological, and hematological parameters, and lateral index. RESULTS: Cognitrax demonstrated that the reaction time significantly improved in the quercetin glycoside intake group. The CBF measurement suggested that quercetin glycoside intake could likely suppress the decrease in cerebral blood volume, CBF, and cerebral activity owing to stress alleviation and inhibition of the accumulation of amyloid ß (Aß), a waste product in the brain, although there were no significant differences between the groups. CONCLUSIONS: Quercetin glycoside intake as a beverage could improve reaction time and may potentially inhibit the decrease in CBF and suppress Aß accumulation.

Continuous partially hydrolyzed guar gum intake reduces cold-like symptoms: a randomized, placebo-controlled, double-blinded trial in healthy adults.

OBJECTIVE: Partially hydrolyzed guar gum (PHGG), a water-soluble dietary fiber produced by the controlled partial enzymatic hydrolysis of guar gum beans, has various physiological roles. PHGG is expected to influence the immune function and prevent infections. The objective of this study was to examine the effect of continuous ingestion of PHGG for 12 weeks on the development of cold-like symptoms. PATIENTS AND METHODS: A placebo-controlled, double blind, randomized, parallel-group comparative study was conducted. 96 healthy Japanese adults received 5.2 g PHGG or placebo daily for 12 weeks. Cold-like symptoms were assessed based on patient diary, and the levels of short-chain fatty acids (SCFAs) in stool and blood immune markers at baseline and at weeks 6 and 12. RESULTS: The cumulative number of "no symptoms" days for all symptoms was significantly larger in the PHGG than in the placebo group. The result of the analysis by severity of cold-like symptoms also showed significant differences, with the PHGG group having a lower severity of cold-like symptoms. Propionic acid at weeks 6 and 12 and n-butyric acid and total SCFAs at week 12 were significantly higher in the PHGG than in the placebo group. The Interferon-γ level was significantly lower at week 6 in the PHGG than in the placebo group. CONCLUSIONS: PHGG intake may affect immune function and suppress cold-like symptoms through the production of SCFAs in healthy adults.

Role of macrophage migration inhibitory factor in age-related hearing loss.

Hearing loss related to aging is the most common sensory disorder among elderly individuals. Macrophage migration inhibitory factor (MIF) is a multi-functional molecule. The aim of this study was to identify the role of MIF in the inner ear. MIF-deficient mice (MIF(-/-) mice) of BALB/c background and wild-type BALB/c mice were used in this study. Expression of MIF protein in the inner ear was examined by immunohistochemistry in wild-type mice (WT). The hearing function was assessed by the click-evoked auditory brainstem response in both MIF(-/-) mice and WT at 1, 3, 6, 9, 12, and 18months of age. Morphological examination of the cochlea was also performed using scanning electron microscopy and light microscopy. MIF was observed in the spiral ligament, stria vascularis, Reissner's membrane, spiral ganglion cells (SGCs), saccular macula, and membranous labyrinth. The MIF(-/-) mice had a significant hearing loss as compared with the WT at 9, 12, and 18months of age. In the MIF(-/-) mice, scanning electron microscopy showed that the outer cochlear hair cells were affected, but that the inner cochlear hair cells were relatively well preserved. The number of SGCs was lower in the MIF(-/-) mice. MIF was strongly expressed in the mouse inner ear. Older MIF(-/-) mice showed accelerated age-related hearing loss and morphological inner ear abnormalities. These findings suggest that MIF plays an important role in the inner ear of mice.

DNA vaccination targeting macrophage migration inhibitory factor prevents murine experimental colitis.

Previous studies have shown that neutralization of macrophage migration inhibitory factor (MIF) by anti-MIF antibody reduces intestinal inflammation in mice. In this study we tested whether or not anti-MIF autoantibody induced by DNA vaccine targeting MIF protects mice against experimental colitis. Mice were administered a MIF-deoxyribonucleic acid (DNA) vaccine by introducing oligonucleotides encoding helper T epitope into the cDNA sequence of murine MIF by in vivo electroporation. Preventive effects of this method against dextran sulphate sodium-induced (DSS) colitis were evaluated. Mice administered with MIF-DNA vaccine raised values of autoantibody significantly. The clinical and histological findings of colitis induced by 3·0% DSS solution were ameliorated significantly in mice treated with MIF-DNA vaccine compared with saline or pCAGGS-treated mice given DSS. Myeloperoxidase activity, infiltration of F4/80-positive staining cells and the levels of proinflammatory cytokines were suppressed in the colon of MIF-DNA vaccine treated mice compared with saline or pCAGGS-treated mice exposed to DSS. Our results suggest that immunization with helper T epitope DNA-vaccine targeting MIF may be a useful approach for the treatment of colitis including inflammatory bowel diseases.

Serum macrophage migration inhibitory factor (MIF) levels after allogeneic hematopoietic stem cell transplantation.

Macrophage migration inhibitory factor (MIF) may play an important role in the pathogenesis of acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT), as MIF plays an important role to regulate the production of tumor necrosis factor-alpha (TNF-alpha), one of the inflammatory cytokines which induces and exacerbates aGVHD. We examined the association between serum MIF levels and aGVHD vs. chronic GVHD (cGVHD) in allo-SCT patients in this study. We found a significant increase in the peak serum MIF (14.46 ng +/- 1.47 ng/ml) at onset in patients that developed aGVHD (n = 23, P = 0.009). We also found that mean serum MIF levels in patients who developed extensive type cGVHD within 6 months (12.58 +/- 2.18 ng/ml, n = 13) were significantly higher than MIF levels before allo-HSCT (7.86 +/- 1.17 ng/ml, n = 19, P = 0.04). Therefore, we speculated that serum MIF levels increase during the active phase of both aGVHD and cGVHD.

A novel DNA vaccine-targeting macrophage migration inhibitory factor improves the survival of mice with sepsis.

Sepsis is a common and frequently fatal condition and there is an urgent need for new therapies that will further reduce sepsis-induced mortality. Macrophage migration inhibitory (MIF) factor is important in the regulation of innate and adaptive immunity and is believed to play a key regulatory role in sepsis and autoimmune disease. As MIF deficiency or immunoneutralization protects mice or rats from fatal endotoxic shock or other inflammatory diseases, we examined whether DNA vaccination against this molecule would also be protective. DNA vaccines can stimulate both humoral and cellular immunity simultaneously and have been shown to be effective against a variety of pathogens or cytokine-driven pathologies. Mice were immunized with a MIF/tetanus toxin (TTX) DNA vaccine and sepsis was then induced by lipopolysaccharide or cecal ligation and puncture. The MIF/TTX DNA-vaccinated mice were protected from the lethal effect of sepsis compared with control-vaccinated mice in both models. Compared with the control-vaccinated mice, the MIF/TTX DNA-vaccinated mice also showed significantly lower serum tumor necrosis factor (TNF)-alpha protein levels and reduced mRNA expression of TNF-alpha, interleukin (IL)-1beta, IL-6, macrophage inflammatory protein-2 and Toll-like receptor-4 in the lungs. Thus, the MIF/TTX DNA vaccine may be useful for the prophylaxis of septic shock.

The responses of extrinsic fibroblasts infiltrating the devitalised patellar tendon to IL-1beta are different from those of normal tendon fibroblasts.

In order to clarify the role of cytokines in the remodelling of the grafted tendon for ligament reconstruction we compared the responses to interleukin (IL)-1beta, platelet-derived growth factor (PDGF)-BB and transforming growth factor (TGF)-beta1 of extrinsic fibroblasts infiltrating the frozen-thawed patellar tendon in rats with that of the normal tendon fibroblasts, in regard to the gene expression of matrix metalloproteinase (MMP)-13, using Northern blot analysis. We also examined, immunohistologically, the local expression of IL-1beta, PDGF-BB, and TGF-beta1 in fibroblasts infiltrating the frozen-thawed patellar tendon. Northern blot analysis showed that fibroblasts derived from the patellar tendon six weeks after the freeze-thaw procedure in situ showed less response to IL-1beta than normal tendon fibroblasts with respect to MMP-13 mRNA gene expression. The immunohistological findings revealed that IL-1beta was over-expressed in extrinsic fibroblasts which infiltrated the patellar tendon two and six weeks after the freeze-thaw procedure in situ, but neither PDGF-BB nor TGF-beta1 was over-expressed in these extrinsic fibroblasts. Our findings indicated that IL-1beta had a close relationship to matrix remodelling of the grafted tendon for ligament reconstruction, in addition to the commencement of inflammation during the tissue-healing process.

Blockade of macrophage migration inhibitory factor (MIF) prevents the antigen-induced response in a murine model of allergic airway inflammation.

OBJECTIVE AND DESIGN: The role of macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, was tested using a mouse asthma model. MATERIALS: One hundred and four male BALB/c mice were used in this study. TREATMENT: Mice were actively sensitized with an intraperitoneal injection of ovalbumin (OVA) and challenged with repeated nebulization of 1 w/v% OVA. Polyclonal anti-MIF antibody was intraperitoneally injected at 10 mg/kg during the antigen challenge period. METHODS: Bronchoalveolar lavage (BAL) was performed 8 h after the last challenge. Airway hyperresponsiveness to inhaled methacholine was measured 24 h after the last challenge. RESULTS: Antigen challenge to immunized mice induced increase in inflammatory cells and concentration of Th2 cytokines in BAL fluid (BALF), and caused the development of airway hyperresponsiveness. Anti-MIF antibody significantly decreased the numbers of inflammatory cells including macrophages, eosinophils, lymphocytes and neutrophils in BALF from OVA-challenged mice. Prednisolone decreased the numbers of eosinophils, lymphocytes and neutrophils but not macrophages. Anti-MIF antibody reduced airway hyperresponsiveness. Anti-MIF antibody affected neither the cytokine levels in BALF nor the IgE levels in serum. CONCLUSION: MIF was involved in the antigen-induced inflammatory cell accumulation in the lung and airway hyperresponsiveness without affecting immune responses.

Role of macrophage migration inhibitory factor in ovalbumin-induced airway inflammation in rats.

Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine that reportedly counteracts the anti-inflammatory effect of endogenous glucocorticoids. There have only been a few reports that demonstrate a potential link between MIF and bronchial asthma. In an attempt to further clarify the precise role of MIF in asthma, the present authors examined the effect of anti-MIF antibody (Ab) on airway inflammation and airway hyperresponsiveness in an ovalbumin-immunised rat asthma model. Actively immunised Brown Norway rats received ovalbumin inhalation with or without treatment of anti-MIF Ab. The levels of MIF in bronchoalveolar lavage fluid were significantly elevated after the ovalbumin challenge. An immunohistochemical study revealed positive immunostaining for MIF in bronchial epithelium, even in nonsensitised rats, and the MIF staining in bronchial epithelium was enhanced after the ovalbumin challenge. Anti-MIF Ab significantly decreased the number of total cells, neutrophils and eosinophils in the bronchoalveolar lavage fluid of the ovalbumin-challenged rats, and also attenuated the ovalbumin-induced airway hyperresponsiveness to ovalbumin and methacholine. However, anti-MIF Ab did not affect the level of serum ovalbumin-specific IgE, suggesting that anti-MIF Ab did not suppress immunisation itself. The results indicate that macrophage migration inhibitory factor plays a crucial role in airway inflammation and airway hyperresponsiveness in asthma.

Promoter polymorphism in the macrophage migration inhibitory factor gene is associated with obesity.

OBJECTIVE: To explore the association of promoter polymorphisms of macrophage migration inhibitory factor (MIF) gene with obesity. SUBJECTS: In total, 213 nondiabetic Japanese subjects. They were divided into three groups according to World Health Organization definitions: lean (body mass index (BMI) <25 kg/m2), overweight (25 < or = BMI < 30 kg/m2) and obese (BMI> or = 30 kg/m2). METHODS: We examined two polymorphic loci in the MIF gene in the subjects: a single-nucleotide polymorphism at position -173 (G/C) and a CATT-tetranucleotide repeat polymorphism at position -794, which both can affect promoter activity in different cells. RESULTS: We detected four alleles: 5-, 6-, 7- and 8-CATT at position -794. Genotypes without the 5-CATT allele (X/X, X refers to 6-, 7- or 8-CATT alleles) were more common in obese subjects than in lean or overweight groups (P = 0.013). The X-CATT allele was more frequent in obese subjects than in lean or overweight subjects (P = 0.030). In contrast, -173G/C was not associated with obesity. Among the haplotypes of the two promoter polymorphisms, G/5-CATT ((-173G/C)/(-794[CATT](5-8))) was associated with a decreased risk of obesity (P = 0.025) and G/6-CATT with an increased risk of overweight (P=0.028). CONCLUSION: Promoter polymorphism in the MIF gene is linked with obesity.

Role for macrophage migration inhibitory factor in asthma.

Macrophage migration inhibitory factor (MIF) is an immunologic regulator that is expressed in inflammatory and autoimmune disorders. We investigated MIF's role in asthma using genetic approaches in a mouse model and in a cohort of asthma patients. Mice genetically deficient in MIF that were primed and aerosol-challenged with ovalbumin showed less pulmonary inflammation and lower airway hyperresponsiveness than genetically matched, wild-type controls. MIF deficiency also resulted in lower titers of specific IgE, IgG(1), and IgG(2a), and decreased pulmonary, T(H)2 cytokine levels. IL-5 concentrations were lower and corresponded to decreased eosinophil numbers in bronchoalveolar lavage fluid. T cell studies also showed a lower level of antigen-specific responses in MIF-KO versus wild-type mice. In an analysis of 151 white patients with mild, moderate, or severe asthma (Global Initiative for Asthma criteria), a significant association was found between mild asthma and the low-expression, 5-CATT MIF allele. Pharmacologic inhibition of MIF may be beneficial and could be guided by the MIF genotype of affected individuals.

Macrophage migration inhibitory factor contributes to the development of acute dextran sulphate sodium-induced colitis in Toll-like receptor 4 knockout mice.

Toll-like receptor 4 (TLR4), which recognizes lipopolysaccharides, plays an important role in the innate immune response. In this study, we investigated the role of TLR4 in the development of experimental colitis with regard to the biological actions of macrophage migration inhibitory factor (MIF) using TLR4 null ((-/-)) mice. TLR4(-/-) mice were given 2% dextran sulphate sodium (DSS) in drinking water to induce colitis, which was clinically and histologically as severe as that seen in wild-type (WT) mice. The level of tumour necrosis factor (TNF)-alpha in colon tissues was increased in WT mice but unchanged in TLR4(-/-) mice. The level of myeloperoxidase (MPO) activity in colon tissues was increased by DSS administration in both TLR4(-/-) and WT mice. The expression of MIF was up-regulated in the colons of TLR4(-/-) mice with acute DSS-induced colitis. An anti-MIF antibody significantly suppressed colitis and elevation of matrix metalloproteinase-13 in TLR4(-/-) mice. The current results obtained from TLR4(-/-) mice provide evidence that MIF plays a critical role in the development of acute DSS-induced colitis.

Transgenic over-expression of macrophage migration inhibitory factor renders mice markedly more susceptible to experimental colitis.

Enhanced production of macrophage migration inhibitory factor (MIF) is recognized in patients with inflammatory bowel disease (IBD) and mice with experimental colitis; however, the precise molecular function of MIF in colitis is not fully understood. To further investigate this matter, we examined the pathological features of MIF transgenic mice with dextran sulphate sodium (DSS)-induced colitis. We generated transgenic mice carrying a murine MIF cDNA driven by a cytomegalovirus enhancer and a beta-actin/beta-globin promoter. Mice were orally administered 1-4% DSS in drinking water for 7 days. Clinical disease activity, survival and histological features were evaluated. The level of myeloperoxidase (MPO) activity in the colon tissue was measured to assess neutrophil infiltration. The level of corticosterone in the serum was measured by enzyme linked-immunosorbent assay (ELISA). MIF mRNA and protein were markedly up-regulated in the colon and serum obtained from MIF transgenic mice. The severity of the colitis induced by 1% DSS treatment was markedly higher in MIF transgenic mice than in wild-type mice. We also found that MPO activity was significantly higher in MIF transgenic mice than wild-type mice in response to DSS stimulation. Interestingly, the corticosterone level remained unchanged in MIF transgenic mice. MIF enhances DSS-induced colitis, in part via neutrophil accumulation and inhibition of glucocorticoid bioactivity.

Promoter region polymorphism of macrophage migration inhibitory factor is strong risk factor for young onset of extensive alopecia areata.

We have demonstrated that serum macrophage migration inhibitory factor (MIF) was significantly elevated in patients with extensive alopecia areata (AA). Recently, functional polymorphisms have been identified in the MIF promoter region. To address the functional and prognostic relevance of the -173G/C and -794[CATT]5-8 repeat polymorphisms in MIF genes in patients with extensive AA, 113 patients with extensive AA and 194 healthy controls were genotyped. We found that MIF-173*C was a risk factor for early onset (<20 years) of extensive AA (odds ratio for GC heterozygotes with -173G/C was 4.88 (95% CI, 2.04-11.8), P=0.00038; odds ratio for CC homozygotes with -173G/C was 10.42 (95% CI, 2.56-43.5), P=0.0011). We found no statistically significant differences in the genotype frequencies of the -794[CATT]5-8 repeat polymorphism and extensive AA. These results suggest that polymorphisms within the MIF-173*C allele confer an increased risk of susceptibility to the extensive forms of AA, especially with an early onset of disease. MIF is therefore suggested to be closely implicated in the pathogenesis of the more extensive forms of AA.

Aqueous levels of macrophage migration inhibitory factor and monocyte chemotactic protein-1 in patients with diabetic retinopathy.

AIMS: To investigate the relationship of aqueous macrophage migration inhibitory factor (MIF) and monocyte chemotactic protein-1 (MCP-1) levels with the clinical stage of diabetic retinopathy. METHODS: We assayed MIF and MCP-1 levels in aqueous humour samples obtained from 40 diabetic patients (49 eyes) and 24 non-diabetic patients (31 eyes) using enzyme-linked immunosorbent assay. According to the clinical stage of diabetic retinopathy, the diabetic patients were classified into non-diabetic retinopathy (11 eyes), non-proliferative diabetic retinopathy (14 eyes) and proliferative diabetic retinopathy (24 eyes). RESULTS: The aqueous levels of MIF (mean +/- sd) were 6.34 +/- 4.53 ng/ml in proliferative diabetic retinopathy, 3.22 +/- 1.71 ng/ml in non proliferative diabetic retinopathy, 1.25 +/- 0.96 ng/ml in non-diabetic retinopathy and 1.07 +/- 0.94 ng/ml in non-diabetic patients. Significant differences were found among these four groups (P < 0.0001). Aqueous MCP-1 levels were 1668.6 +/- 1442.3 pg/ml in proliferative diabetic retinopathy, 1528.6 +/- 1994.6 pg/ml in non-proliferative diabetic retinopathy, 690.2 +/- 402.1 pg/ml in non-diabetic retinopathy and 622.7 +/- 245.3 pg/ml in non-diabetic patients. Significant differences were also found among these four groups (P < 0.0001). After correcting for total aqueous protein, the ratios of MIF and MCP-1 to total protein remained significantly correlated with the clinical stage of diabetic retinopathy (P < 0.0001, P = 0.0004, respectively). The ratios of MIF to total protein significantly correlated with the ratios of MCP-1 to total protein in diabetic patients (r = 0.680, P < 0.0001). CONCLUSIONS: Aqueous MIF levels significantly correlated with aqueous MCP-1 levels and the clinical stage of diabetic retinopathy. The results suggest that MIF has a co-operative role with MCP-1 in the progression of diabetic retinopathy.

Cetirizine, an H1-receptor antagonist, suppresses the expression of macrophage migration inhibitory factor: its potential anti-inflammatory action.

BACKGROUND: H1-receptor antagonists are often effective in the treatment of allergic disorders such as atopic dermatitis. Cetirizine, a putative H1-receptor antagonist, has recently been shown to have anti-inflammatory properties through the inhibition of leucocyte recruitment and activation, and by the reduction of ICAM-1 expression on keratinocytes. OBJECTIVE: To further elucidate the anti-inflammatory properties of cetirizine, we first examined its effects on antigen-induced eosinophilia and neutrophila in vivo. We then examined the anti-inflammatory effects of cetirizine on a human keratinocyte A431cell line. METHODS: Mice were sensitized subcutaneously with ragweed pollen and were challenged intraperitoneally with the allergen. Cetirizine diluted in sterile water (0-20 mg/kg) or only sterile water was administered orally. Peritoneal cells were obtained at 8 and 24 h after challenge. The eosinophilia and neutrophilia induced by ragweed pollen extract were quantitated. Macrophage migration inhibitory factor (MIF), macrophage inflammatory protein 2 (MIP-2) and eotaxin contents of peritoneal fluid were also measured by mouse ELISA. The effects of cetirizine on MIF-induced IL-8 production in A431 cells were examined by ELISA. The effects of cetirizine on MIF expression and production in A431 cells were examined by human MIF ELISA and Northern blot analysis. RESULTS: Eosinophilia and neutrophilia induced by ragweed pollen extract were found to be significantly reduced in cetirizine-treated mice (20 mg/kg). MIF, a pleuripotent cytokine, was significantly decreased at 8 and 24 h in the peritoneal fluid by cetirizine treatment. MIP-2 and eotaxin were also decreased 8 and 24 h, respectively, after challenge in the peritoneal fluid with cetirizine treatment. MIF stimulates IL-8 production in A431 cells. We found that MIF production in A431 cells was inhibited by 10 microm cetirizine. Consistent with this, cetirizine significantly inhibited MIF-induced IL-8 production. CONCLUSION: These results suggest that cetirizine exerts its anti-inflammatory effects by inhibiting MIF as well as IL-8 production, such as those involved in inflammatory allergic skin disease, suggesting a broad spectrum of action beyond its mere H1-receptor-antagonistic function.

Immunohistochemical study of macrophage migration inhibitory factor in rat liver fibrosis induced by thioacetamide.

Macrophage migration inhibitory factor (MIF) is a molecule known to regulate macrophage accumulation at sites of inflammation. To elucidate the role of MIF in progression of liver fibrosis, the immunohistochemical localization of MIF and macrophages in the liver were examined. Male Wistar rats received thioacetamide (TA) injections (200 mg/kg, i.p.) for 1 or 6 weeks. In biochemical and histological tests, it was confirmed that liver fibrosis was induced. In immunohistochemical analyses, the expression of MIF protein was seen in hepatocytes in the areas extending out from the central veins to the portal tracts. In particular, at 6 weeks, immunoreactivity was detected in degenerated hepatocytes adjacent to the fibrotic areas but hardly observed in the fibrotic areas. On the other hand, a number of exudate macrophages stained by antibody ED1 were seen in the areas from the central veins to the portal tracts at 1 week and in the fibrotic areas at 6 weeks. Macrophages also showed a significant increase in number as compared with controls. These results revealed that there was a close relationship between the appearance of MIF expression and ED1-positive exudate macrophages in degenerated hepatocytes during the progression of TA-induced liver fibrosis.

Monocyte chemotactic protein-1 in the vitreous of patients with proliferative diabetic retinopathy.

PURPOSE: To investigate the correlation between monocyte chemotactic protein-1 (MCP-1) levels in the vitreous and clinical findings in eyes with proliferative diabetic retinopathy (PDR). METHODS: We assayed MCP-1 levels by ELISA in vitreous samples of 88 consecutive patients with PDR (52 eyes) and macular holes or idiopathic epimacular membrane (controls, 36 eyes). RESULTS: The level of MCP-1 in the vitreous was 2,097.5 +/- 1,099.4 pg/ml (mean +/- SD) in PDR, and 504.3 +/- 405.6 pg/ml in the controls. In PDR eyes, multivariate regression analysis revealed a significant association between MCP-1 levels in the vitreous and the degree of proliferative membrane, and a significant negative association between MCP-1 levels and the extent of preoperative retinal photocoagulation. CONCLUSION: The results suggest that MCP-1 may play a role in the development of the proliferative phase of PDR.

Macrophage migration inhibitory factor as a redox-sensitive cytokine in cardiac myocytes.

OBJECTIVE: Macrophage migration inhibitory factor (MIF), which plays a pivotal role in the control of inflammatory responses, was first characterized as a T-cell cytokine, but later was also found as a pituitary peptide released in response to infection and stress. However, MIF's role and expression in the myocardium has never been reported. The goal of this study is to examine MIF in the myocardium. METHODS AND RESULTS: MIF protein and mRNA levels were assayed using enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR), respectively. Increased MIF concentrations were detected in the sera of patients with acute myocardial infarction (AMI). In cultured rat cardiac myocytes, significant amounts of MIF were produced in response to hypoxia and hydrogen peroxide (H(2)O(2)), but not to angiotensin II, endothelin-1, interleukin-1beta (IL-1beta) or tumor necrosis factor alpha (TNFalpha). H(2)O(2)-induced MIF production increased in a time- and dose-dependent manner and was completely abolished in the presence of catalase. H(2)O(2) also induced MIF mRNA expression. The H(2)O(2)-induced MIF production was completely inhibited by the protein kinase C (PKC) inhibitor GF109203X, partially inhibited by the tyrosine kinase inhibitor herbimycin A, and uninhibited by calcium chelation or phorbol ester-sensitive PKC down-regulation. This suggests that H(2)O(2)-induced MIF production is mediated by an atypical PKC isoform. DNA microarray analysis revealed that 52 genes were preferentially expressed in response to MIF. Of these, the MIF-induced expression of both glutathione S-transferase (GST) and lipopolysaccharide-induced CXC chemokine (LIX) mRNAs was confirmed using RT-PCR analysis. CONCLUSION: The present results suggest that MIF is expressed by the myocardium in response to redox stress and may play a role in the pathogenesis of myocardial ischemia.

Serum level of macrophage migration inhibitory factor as a useful parameter of clinical course in patients with Wegener's granulomatosis and relapsing polychondritis.

Novel biological activities of macrophage migration inhibitory factor (MIF) have been rediscovered. In addition, elevation of the serum MIF level has been reported in different types of disorders, including various inflammatory and autoimmune diseases. In the present study, serum MIF levels were analyzed in patients with Wegener's granulomatosis (WG) and relapsing polychondritis. It was shown that the serum MIF levels in these patients were significantly higher than those of normal healthy controls. In a WG patient, the MIF level showed a good correlation with clinical symptoms and C-ANCA titers. Thus, serum MIF levels will be a useful laboratory parameter for following the clinical course of WG patients and determining medical treatment. The immunopathologic roles of MIF in these diseases are discussed.