Thioredoxin 1 (Trx 1) is a redox-active small protein ubiquitously present in human body. It is one of the defensive proteins induced in response to various stress conditions. In addition to its anti-oxidative effect by dithiol-disulfide exchange in its active site, Trx 1 has anti-apoptotic and anti-inflammatory effects. Trx 1 overexpression has been shown to be effective in a wide variety of animal models for oxidative and inflammatory disorders. An administration of recombinant Trx 1 protein is also effective in animal models especially for severe acute lung diseases where Trx 1 is likely to act with its anti-inflammatory properties. Trx 1 in circulation shows anti-chemotactic effects for neutrophils and inhibitory effects against macrophage migration inhibitory factor (MIF). Neovascularization is also suppressed by Trx 1 via inhibition of the complement activation. Here we discuss precise mechanisms of Trx 1 and potential therapeutic approach of this molecule.

OBJECTIVE

To evaluate serum and synovial fluid (SF) levels of macrophage migration inhibitory factor (MIF) and in vitro MIF production by peripheral blood mononuclear cells (PBMCs) in patients with juvenile idiopathic arthritis (JIA).

METHODS

Serum, SF, and culture supernatant levels of MIF were measured by enzyme-linked immunosorbent assay. Production of MIF by PBMCs was investigated by culturing PBMCs in the absence or presence of 2 different concentrations of concanavalin A.

RESULTS

Serum MIF levels were increased in patients with JIA, and the highest levels were present in patients with systemic-onset JIA. In systemic-onset JIA, serum levels of MIF correlated with the persistence of systemic features and the number of active joints. PBMCs from patients with systemic-onset JIA, when cultured under unstimulated conditions or at suboptimal stimulation, released higher amounts of MIF compared with those from patients with oligoarticular-onset JIA or healthy controls. MIF levels in the SF of patients with systemic-onset JIA were significantly higher than those in patients with oligoarticular-onset JIA. In individual joints, in both systemic-onset JIA and oligoarticular-onset JIA, SF MIF levels were inversely correlated with the duration of the clinical remission induced by intraarticular administration of triamcinolone hexacetonide.

CONCLUSIONS

MIF appears to be a relevant cytokine in the pathogenesis of JIA, particularly in systemic-onset JIA.

OBJECTIVE

Gestational diabetes mellitus (GDM) is thought to modify the pattern of placental transcriptome. In a microarray study and a confirmatory quantitative real-time reverse transcription-polymerase chain reaction study, we investigated global placental gene expression in GDM.

METHODS

Ribonucleic acid was extracted from placental samples collected from 19 GDM cases and 21 controls. Oligonucleotide probes representing 22,000 genes were used to measure gene expression. Differential gene expression was evaluated using the Student t test, fold change assessment, and significance analysis of microarrays. Path analysis was used to assess functions and functional relationships of differentially expressed genes.

RESULTS

Sixty-six genes participating in cell functions involving cell activation, immune response, organ development, and regulation of cell death were differentially expressed in GDM placentas. These genes include previously described candidate genes (eg, LEP, CEBPA, and MIF), genes with related functions (eg, ADFP), and novel genes (eg, AQP3).

CONCLUSIONS

Expression of genes responsible for diverse biologic processes are modified in GDM.

We have cloned the macrophage migration inhibitory factor (MIF)-like protein (Anisakis simplex (As)-MIF) from larvae of the whale worm (Anisakis simplex third-stage larvae). Asthma was induced in the mice using OVA/alum, with or without various concentrations of rAs-MIF treatment before OVA/alum challenge. Treatment with rAs-MIF coupled with OVA/alum during the challenge period induced a complete inhibition of eosinophilia and goblet cell hyperplasia within the lung and profoundly ameliorated the development of lung hyperreactivity. Also, rAs-MIF was shown to reduce profoundly the quantity of Th2-related cytokines (IL-4, IL-5, and IL-13) in the bronchial alveolar lavage fluid and allergen-specific IgG2a in sera. IL-10 and TGF-beta levels in the bronchoalveolar lavage fluid of the rAs-MIF-treated group were significantly higher than in the other groups. Additionally, CD4(+)CD25(+)Foxp3(+) T cells (regulatory T) were recruited to the spleen and lungs of the rAs-MIF-treated mice, but this recruitment was inhibited by anti-rAs-MIF Ab.

There is a growing interest in the role that cancer biomarkers, metastasis-related molecules, and chemokines may play in the development and progression of various cancers. However, few studies have addressed the reliability of such biomarkers in healthy individuals over time. The objective of this study was to investigate the temporal reliability of multiple proteins in serum samples from healthy women who donated blood over successive years. Thirty five, postmenopausal women with two, repeated annual visits, and thirty, premenopausal women with three, repeated annual visits were randomly selected among eligible subjects from an existing, prospective cohort. Multiplexing Luminex xMAPTM technology was used to measure the levels of 55 serum proteins representing cancer antigens, chemokines, angiogenic and anti-angiogenic factors, proteases, adipokines, apoptotic molecules, and other markers in these women. The biomarkers with high detection rates >> 60%) and acceptable reliability (intraclass correlation coefficient, ICCs>> or = 0.55) using xMAPTM method were: cancer antigens: AFP, CA 15-3, CEA, CA-125, SCC, SAA; growth factors/related molecules: ErbB2, IGFBP-1; proteases and adhesion molecules: MMP-1, 8, 9, sE-selectin, human kallikreins (KLK) 8,10, ICAM-1, VCAM-1, chemokines: fractalkine, MCP-1,2, RANTES, MIP-1alpha, MIP-1beta, Eotaxin, GRO-alpha, IP-10; inhibitors of angiogenesis: angiostatin and endostatin; adipokines leptin and resistin; apoptotic factor: Fas, and other proteins mesothelin, myeloperoxidase (MPO), and PAI-1. The rest of the biomarkers under investigation either had ICCs less than 0.55 or had low levels of detection (< 60%). These included cancer antigens: CA 19-9, CA 72-4, MICA, S100, TTR, ULBP1, ULBP2, ULBP3; proteases: MMP 2, 3, 7, 12, 13; chemokines: MCP-3, MIF, MIG; adipokines: leptin and resistin; apoptotic factors: FasL, DR5, Cyfra 21-1; and inhibitors of angiogenesis and other markers: thrombospondin and heat shock protein (HSP) 27. In conclusion, 34 out of the 55 biomarkers investigated were present in detectable levels in>> 60% of the samples, and with an ICC>> or = 0.55, indicating that a single serum measurement can be used in prospective epidemiological studies using the xMAPTM method.

BACKGROUND

An active angiogenesis is required for ectopic endometrial tissue growth. Our previous studies led to the identification of macrophage migration inhibitory factor (MIF), which is markedly elevated in active, vascularized, and early-stage endometriotic lesions, as a potent mitogenic factor for endothelial cells.

OBJECTIVE

Our objective was to study the mechanisms by which MIF may stimulate angiogenesis in ectopic endometrial implantation sites.

METHODS

Primary cultures of ectopic endometrial cells were exposed to MIF, and the release of major angiogenic factors with targeted disruption of MIF signaling pathways was assessed.

METHODS

Patients were women found to have endometriosis during laparoscopy.

METHODS

The study was conducted at a hospital and reproduction research laboratory.

METHODS

Biopsies were removed from endometriotic lesions.

METHODS

Vascular endothelial cell growth factor (VEGF), IL-8, and monocyte chemotactic protein-1 (MCP-1) mRNA and protein levels and expression and small interfering RNA silencing of MIF CD74/CD44 receptor complex and phosphorylation of ERK and p38 MAPKs were evaluated.

RESULTS

MIF markedly up-regulated VEGF, IL-8, and MCP-1 expression in endometriotic cells. Such an effect was abolished by (S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester (ISO-1), a specific inhibitor of MIF, and significantly down-regulated after specific small interfering RNA silencing of CD44 or CD74. MIF treatment strongly activated ERK and p38 MAPKs, and specific inhibitors of both pathways completely blocked basal and MIF-induced VEGF, IL-8, and MCP-1 synthesis.

CONCLUSIONS

These results show for the first time that MIF exerts a potent indirect angiogenic effect by interacting with ectopic endometrial cells and inducing the secretion of major angiogenic factors via CD44, CD74, and MAPK signaling pathways and provide evidence for a possible new mechanism underlying endometriosis development and pathophysiology.

OBJECTIVE

The purpose of this study was to compare changes in muscle damage indicators following 24 maximal eccentric actions of the elbow flexors (Max-ECC) between the arms that had been previously trained either eccentrically or concentrically for 8 wk.

METHODS

Fifteen subjects performed three sets of 10 repetitions of eccentric training (ECC-T) with one arm and concentric training (CON-T) with the other arm once a week for 8 wk using a dumbbell representing 50% of maximal isometric force of the elbow flexors (MIF) determined at the elbow joint of 90 degrees (1.57 rad). The dumbbell was lowered from a flexed (50 degrees, 0.87 rad) to an extended elbow position (180 degrees, 3.14 rad) in 3 s for ECC-T, and lifted from the extended to the flexed position in 3 s for CON-T. Max-ECC was performed 4 wk after CON-T and 6 wk after ECC-T. Changes in MIF, range of motion (ROM), upper arm circumference (CIR), muscle soreness (SOR), and plasma creatine kinase (CK) activity were compared between the ECC-T and CON-T arms.

RESULTS

The first ECC-T session produced larger decreases in MIF and ROM, and larger increases in CIR and SOR compared with CON-T. CK increased significantly (P < 0.01) and peaked 4 d after the first training session, but did not increase in the following sessions. All measures changed significantly (P < 0.01) following Max-ECC; however, the changes were not significantly different between ECC-T and CON-T arms.

CONCLUSIONS

These results showed that ECC-T did not mitigate the magnitude of muscle damage more than CON-T, and CON-T did not exacerbate muscle damage.

OBJECTIVE

Macrophage migration inhibitory factor (MIF), a central cytokine of the innate immunity, has been reported to contribute to the development of cardiovascular disease. MIF is expressed in atherosclerotic lesions in humans, and gene deletion and antibody inhibition studies in animal models indicated that MIF may be cause rather than consequence of atherosclerosis. We sought to assess the triangular association between MIF genotypes, circulating MIF levels and risk for incident coronary heart disease (CHD) in the large, prospective, population-based MONICA/KORA case-cohort study (Augsburg, Southern Germany).

METHODS

MIF genotypes, haplotypes and serum concentrations were determined in 363 individuals with incident CHD and 1908 individuals without CHD during follow-up (mean follow-up time 10.3 years).

RESULTS

Circulating MIF concentrations were not associated with the risk for CHD. In women, carriers of the minor alleles rs755622C and rs2070766G had a higher risk for incident CHD, and a haplotype that contained these two minor alleles was significantly associated with increased risk for CHD (HR 2.44, 95%CI 1.30-4.59).

CONCLUSIONS

The lack of association between serum levels and incident CHD indicates that MIF may not be a novel biomarker for CHD risk. However, the association of a haplotype containing the rs755622C allele, which has been reported before to increase the susceptibility for various other proinflammatory conditions, with CHD points towards a role for MIF in local vascular inflammation and atherogenesis.

Small polydisperse circular (spc) DNA was isolated from mouse thymocytes and cloned into the HindIII site of lambda vector Charon 7. Fifty-six recombinants from this spc DNA library were analyzed. R repeats, which were originally found near immunoglobulin genes, were enriched in spc DNA clones relative to their representation in the chromosome. In one clone, the R sequence was linked to Bam and MIF sequences and the contiguous arrangement was truncated from both ends. In another clone, composite Bam/R and R repeats existed as a pair in inverted repeat orientation. Truncation occurred from the 5' side without affecting the 3' ends. In both clones, short direct repeats flanked the repeated sequences. The possible role of R sequences in transposition and circular formation is discussed.

Macrophage migration inhibitory factor (MIF) expression is increased by angiotensin II (Ang II) within paraventricular nucleus (PVN) neurons of normotensive rats and acts via its intrinsic thiol protein oxidoreductase (TPOR) to counterregulate the central nervous system-mediated pressor action of Ang II. Considering that the PVN-mediated actions of Ang II are enhanced in spontaneously hypertensive rats (SHRs) and contribute to the development of hypertension in these animals, we investigated this MIF regulatory mechanism in SHRs. Here, we have demonstrated that Ang II failed to increase MIF protein expression in the PVN of SHRs. Furthermore, although basal levels of MIF protein and mRNA were similar in the PVN of SHRs and normotensive rats, immunostaining revealed that MIF was either absent from or diminished in PVN neurons of SHRs. AAV2-mediated increases in MIF expression within PVN neurons of young (8 wk old) SHRs produced a chronic attenuation of hypertension and cardiac hypertrophy. However, similar AAV2-mediated transduction of [C60S]-MIF, which lacks TPOR activity, did not alter the development of hypertension or cardiac hypertrophy in SHRs. Collectively, these findings suggest that a lack of MIF expression within PVN neurons contributes to the development of hypertension and cardiac hypertrophy in SHRs.

Dengue virus (DENV) infection can cause mild dengue fever or severe dengue hemorrhage fever (DHF) and dengue shock syndrome (DSS). Serum levels of the macrophage migration inhibitory factor (MIF) have been shown to be correlated with severity and mortality in DENV patients, but the pathogenic roles of MIF in DHF/DSS are still unclear. Increase in vascular permeability is an important hallmark of DHF/DSS. In this study, we found that DENV infection of the human hepatoma cell line (Huh 7) induced MIF production. Conditioned medium collected from DENV-infected Huh 7 cells enhanced the permeability of the human endothelial cell line (HMEC-1) which was reduced in the presence of a MIF inhibitor, ISO-1 or medium from DENV-infected MIF knockdown Huh 7 cells. To further identify whether MIF can alter vascular permeability, we cloned and expressed both human and murine recombinant MIF (rMIF) and tested their effects on vascular permeability both in vitro and in vivo. Indirect immunofluorescent staining showed that the tight junction protein ZO-1 of HMEC-1 was disarrayed in the presence of rMIF and partially recovered when cells were treated with ISO-1 or PI3K/MEK-ERK/JNK signaling pathway inhibitors such as Ly294002, U0126, and SP600215. In addition, ZO-1 disarray induced by MIF was also recovered when CD74 or CXCR2/4 expression of HMEC-1 were inhibited. Last but not least, the vascular permeabilities of the peritoneal cavity and dorsal cutaneous capillary were also increased in mice treated with rMIF. Taken together; these results suggest that MIF induced by DENV infection may contribute to the increase of vascular permeability during DHF/DSS. Therapeutic intervention of MIF by its inhibitor or neutralizing antibodies may prevent DENV-induced lethality.

Myocardial dysfunction is a major consequence of septic shock and contributes to the high mortality of sepsis. We have previously reported that glucan phosphate (GP) significantly increased survival in a murine model of cecal ligation and puncture (CLP)-induced sepsis. In the present study, we examined the effect of GP on cardiac dysfunction in CLP-induced septic mice. GP was administered to ICR/HSD mice 1 h before induction of CLP. Sham surgically operated mice served as control. Cardiac function was significantly decreased 6 h after CLP-induced sepsis compared with sham control. In contrast, GP administration prevented CLP-induced cardiac dysfunction. Macrophage migration inhibitory factor (MIF) has been implicated as a major factor in cardiomyocyte apoptosis and cardiac dysfunction during septic shock. CLP increased myocardial MIF expression by 88.3% (P < 0.05) and cardiomyocyte apoptosis by 7.8-fold (P < 0.05) compared with sham control. GP administration, however, prevented CLP-increased MIF expression and decreased cardiomyocyte apoptosis by 51.2% (P < 0.05) compared with untreated CLP mice. GP also prevented sepsis-caused decreases in phospho-Akt, phospho-GSK-3beta, and Bcl-2 levels in the myocardium of septic mice. These data suggest that GP treatment attenuates cardiovascular dysfunction in fulminating sepsis. GP administration also activates the phosphoinositide 3-kinase/Akt pathway, decreases myocardial MIF expression, and reduces cardiomyocyte apoptosis.

BACKGROUND

Tumor-derived cytokines and their receptors usually take important roles in the disease progression and prognosis of cancer patients. In this survey, we aimed to detect the expression levels of MIF and CXCR4 in different cell populations of tumor microenvironments and their association with survivals of patients with esophageal squamous cell carcinoma (ESCC).

METHODS

MIF and CXCR4 levels were measured by immunochemistry in tumor specimens from 136 resected ESCC. Correlation analyses and independent prognostic outcomes were determined using Pearson's chi-square test and Cox regression analysis.

RESULTS

The expression of CXCR4 in tumor cells was positively associated with tumor status (P = 0.045) and clinical stage (P = 0.044); whereas the expression of CXCR4 in tumor-infiltrating lymphocytes (TILs) and the expression of MIF in tumor cells and in TILs were not associated with clinical parameters of ESCC patients. High MIF expression in tumor cells or in TILs or high CXCR4 expression in tumor cells was significantly related to poor survival of ESCC patients (P < 0.05). Multivariate analysis showed that the expression of MIF or CXCR4 in tumor cells and the expression of MIF in TILs were adverse independent factors for disease-free survival (DFS) and overall survival (OS) in the whole cohort of patients (P < 0.05). Furthermore, the expression of MIF and CXCR4 in tumor cells were independent factors for reduced DFS and OS in metastatic/recurrent ESCC patients (P < 0.05). Interestingly, the expressions of MIF and CXCR4 in tumor cells and in TILs were significantly positively correlated (P < 0.05), and the combined MIF and CXCR4 expression in tumor cells was an independent adverse predictive factor for DFS and OS (P < 0.05).

CONCLUSIONS

The expressions of MIF and CXCR4 proteins in tumor cells and TILs have different clinically predictive values in ESCC.

Macrophage migration inhibitory factor (MIF) is a pro-inflammatory mediator with the ability to induce various immunomodulatory responses and override glucocorticoid-driven immunosuppression. Some of these functions have been linked to the unusual enzymatic properties of the protein, namely tautomerase and oxidoreductase activities. However, there are conflicting reports regarding the functional role of these enzymatic properties in normal physiological homeostasis and disease progression. Therefore, we have produced a highly pure, virtually endotoxin-free recombinant MIF preparation and fully characterized this using a variety of biochemical and biophysical approaches. The recombinant protein, with demonstrable enzymatic activity, was then used to systematically examine the biological activity of MIF. Surprisingly, treatment with MIF alone failed to induce cytokine expression, with the exception of IL-8. However, co-treatment of lipopolysaccharide (LPS) in conjunction with MIF produced synergistic secretion of tumor necrosis factor-alpha, interleukin (IL)-1, and IL-8 compared with LPS alone. The potentiating effect of MIF was seen at physiologically relevant concentrations. These data suggest that MIF has no conventional cytokine activity but, rather, acts to modulate and amplify the response to LPS.

OBJECTIVE

The objective of this study was to investigate the effects of calcitriol on adipocyte and macrophage cytokine expression as well as release and on adipocyte-macrophage cross-talk in local modulation of inflammation.

UNASSIGNED

We investigated calcitriol modulation of the expression of macrophage inhibitory factor (MIF) and macrophage surface-specific protein CD14, two key factors in regulating macrophage function and survival, in differentiated human adipocytes. Calcitriol significantly increased MIF and CD14 expression by 59% and 33%, respectively, while calcium-channel antagonism with nifedipine completely reversed these effects, indicating that calcitriol stimulates MIF and CD14 expression via a calcium-dependent mechanism. Similar results were also found in cultured 3T3-L1 adipocytes; in addition, calcitriol also up-regulated macrophage colony-stimulating factor, macrophage inflammatory protein, interleukin-6 (IL-6) as well as monocyte chemoattractant protein-1 expression in 3T3-L1 adipocytes and stimulated tumor necrosis factor as well as IL-6 expression in RAW 264 macrophages. These effects were blocked by either a calcium-channel antagonist (nifedipine) or a mitochondrial uncoupler (dinitrophenol). Moreover, co-culture of 3T3-L1 adipocytes with RAW 264 macrophages significantly increased the expression and production of multiple inflammatory cytokines in response to calcitriol in both cell types.

CONCLUSIONS

These data demonstrate that calcitriol regulates local inflammation via modulating the interaction between adipocytes and macrophages as well as regulating inflammatory cytokine production in each cell type via calcium-dependent and mitochondrial uncoupling-dependent mechanisms. These data provide further mechanistic explanation for our recent observations that suppression of calcitriol by dietary calcium reduces inflammatory cytokine expression and oxidative stress in adipose tissue.

Embryonic stem (ES) cells and ES cell-derived differentiated cells can be used in tissue regeneration approaches. However, inflammation may pose a major hurdle. To define the inflammatory response of ES and ES cell-derived vascular cells, we exposed these cells to LPS. With the exception of MIF no significant cytokine mRNA levels were observed either at baseline or after stimulation. Further experiments revealed that these cells do not express TLR4. Analysis of the DNA methylation status of the TLR4 upstream region showed increased methylation. Moreover, in vitro methylation suppressed TLR4 promoter activity in reporter gene assays. ChIP assays showed that in this region histones H3 and H4 are hypoacetylated in ES cells. Interestingly, 5-aza-dC or TSA partially relieves this gene repression. Finally, the increased levels of TLR4 observed in ES cells after treatment with 5-aza-dC or TSA confer responsiveness to LPS, as induction of IL-6 and TNFalpha mRNA was detected in endotoxin stimulated ES cells.

The organization of the motoneuron subgroups in the brainstem controlling each extraocular eye muscle is highly stable through the vertebrate species. The subgroups are topographically organized in the oculomotor nucleus (III) and are usually considered to form the final common pathway for eye muscle control. Eye muscles contain a unique type of slow non-twitch, fatigue-resistant muscle fiber, the multiply innervated muscle fibers (MIFs). The recent identification the MIF motoneurons shows that they too have topographic organization, but very different from the classical singly innervated muscle fiber (SIF) motoneurons. The MIF motoneurons lie around the periphery of the oculomotor nucleus (III), trochlear nucleus (IV), and abducens nucleus (VI), slightly separated from the SIF subgroups. The location of four different types of neurons in VI are described and illustrated: (1) SIF motoneurons, (2) MIF motoneurons, (3) internuclear neurons, and (4) the paramedian tract neurons which project to the flocculus. Afferents to the motoneurons arise from the vestibular nuclei, the oculomotor and abducens internuclear neurons, the mesencephalic and pontine burst neurons, the interstitial nucleus of Cajal, nucleus prepositus hypoglossi, the supraoculomotor area and the central mesencephalic reticular formation and the pretectum. The MIF and SIF motoneurons have different histochemical properties and different afferent inputs. The hypothesis that SIFs participate in moving the eye and MIFs determine the alignment seems possible but is not compatible with the concept of a final common pathway.

Chronic kidney disease (CKD) carries an increased risk of cardiovascular disease (CVD). Macrophage migration inhibiting factor (MIF) is a proinflammatory cytokine implicated in the pathogenesis of sepsis, autoimmune disease, atherogenesis, and plaque instability, and is a known cardiac depressant. This post-hoc, cross-sectional study examined whether MIF serum concentrations are elevated in CKD patients. Our study included CKD 3-5 patients with moderate to severe renal dysfunction (n = 257) (mean age SD; 55 +/- 12 years) and 53 controls (60 +/- 12 years). Serum MIF concentrations, measured by enzyme-linked immunosorbent assay (ELISA), were studied in relation to glomerular filtration rate (GFR), presence of CVD, outcome and inflammatory and oxidative stress markers. MIF was significantly elevated in CKD patients compared with controls (CKD: median 676 [range 118-8275 pg/mL] controls: 433 [142-4707] pg/mL; P = 0.008). MIF was also associated with 8-hydroxy-2-deoxyguanosine (8-OH-dG) levels (rho = 0.26; P = 0.001), a marker of oxidative stress, and ICAM-1 levels (rho = 0.14; P = 0.02), a marker of endothelial activation. However, the elevated MIF concentrations were neither correlated with glomerular filtration rate (GFR) nor inflammatory markers such as CRP, IL-6, and TNF. When combining MIF and IL-6 as a marker of inflammation, a significant increase in risk for CVD was found, but when analyzing all-cause mortality, this did not differ significantly with regard to mortality from inflamed patients with low MIF levels. The data suggest that increased serum MIF levels found in CKD is not caused primarily by poor renal function, but is associated with markers of oxidative stress and endothelial activation and may play a role in vascular disease associated with CKD.

Macrophage migration inhibitory factor (MIF), an important pro-inflammatory cytokine, is over-expressed in plaques of psoriasis and increased levels are found in the sera of patients with psoriasis. Promoter polymorphisms of the MIF gene are associated with increased production of MIF and have been found to confer increased risk of susceptibility to chronic inflammatory diseases. We investigated whether there is an association between promoter polymorphisms of the MIF gene and chronic plaque psoriasis. Two hundred and twenty-eight UK caucasian patients with chronic plaque psoriasis, and a control panel of 401 UK caucasian normal volunteers were studied. MIF promoter polymorphisms were genotyped by allelic discrimination, or by a fluorescently labeled primer method, and capillary gel electrophoresis. Carriage of either the MIF-173*C polymorphism or the MIF CATT(7) polymorphism was positively correlated with psoriasis (odds ratios (OR) 1.52 95% confidence intervals (CI) 1.05-2.19 (p=0.024) and OR 1.67 95% CI 1.1-2.5 (p=0.013), respectively. The OR for presence of the CATT(7)-MIF-173(*)C haplotype versus all other haplotypes combined was 1.69 95% CI 1.2-2.5 (p=0.008). The results provide evidence for polymorphisms in the MIF gene, and in particular the CATT(7)-MIF-173(*)C haplotype, being of importance in susceptibility to psoriasis.

OBJECTIVE

Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine important in animal models of rheumatoid arthritis (RA). We investigated the utilization by MIF of mitogen activated protein (MAP) kinase signalling pathways in the stimulation of fibroblast-like synoviocytes (FLS), cyclooxygenase-2 (COX-2), prostaglandin E(2) (PGE(2)), and interleukin 6 (IL-6) and IL-8 expression.

METHODS

Cultured human RA FLS were treated with recombinant MIF. Activation of MAPK was measured by Western blotting and blocked using specific inhibitors. The expression of COX-2, PGE(2), IL-6, and IL-8 were measured using flow cytometry, ELISA, and real-time polymerase chain reaction.

RESULTS

MIF induced the phosphorylation of FLS p38 and extracellular-signal regulated kinase (ERK) MAP kinase. MIF significantly induced COX-2 and IL-6 protein and mRNA expression as well as PGE(2) and IL-8 production. Antagonism of p38 MAP kinase inhibited MIF induction of COX-2, PGE(2), and IL-6. In contrast, antagonism of ERK had no effect on COX-2, PGE(2), or IL-6. Neither antagonist inhibited MIF-induced IL-8.

CONCLUSIONS

MIF activates RA FLS COX-2 and IL-6 expression via p38 MAP kinase activation and induces IL-8 via p38 and ERK MAP kinase-independent pathways.

Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine that is involved in host immune and inflammatory responses, as well as tumorigenesis. However, the regulatory mechanism of MIF function is unclear. Here we report that the NM23-H1 interacts with MIF in cells, as demonstrated by cotransfection and coimmunoprecipitation experiments. Analysis of cysteine (Cys) to serine (Ser) substitution mutants of NM23-H1 (C4S, C109S, and C145S) and MIF (C57S, C60S, and C81S) revealed that Cys(145) of NM23-H1 and Cys(60) of MIF are responsible for complex formation. NM23-H1-MIF complexes were dependent on reducing conditions, such as the presence of dithiothreitol or beta-mercaptoethanol, but not H(2)O(2). NM23-H1 alleviated the MIF-mediated suppression of p53-induced apoptosis and cell cycle arrest by promoting the dissociation of MIF from MIF-p53 complexes. In addition, NM23-H1 significantly inhibited the MIF-induced proliferation of quiescent NIH 3T3 cells through a direct interaction with MIF, and decreased the MIF-induced activation of phosphatidylinositol 3-kinase/PDK1 and p44/p42 extracellular signal-regulated (ERK) mitogen-activated protein kinase. The results of the current study suggest that the NM23-H1 functions as a negative regulator of MIF.

As a result of chronic exposure to high levels of free fatty acids, glucose and inflammatory mediators β-cell apoptosis occurs at the end stage of obesity-associated type 2 diabetes (T2D). One potentially deleterious molecule for β-cell function associated with T2D and obesity in humans is macrophage migration inhibitory factor (MIF). Therefore, the aim of this study was to explore MIF expression in vivo during development of obesity and insulin resistance in high-fat diet (HFD)-fed C57BL/6 mice and whether MIF inhibition could affect β-cell apoptosis and dysfunction induced by palmitic acid (PA) in vitro. Indeed, increase in systemic and locally produced MIF correlated well with the weight gain, triglyceride upregulation, glucose intolerance and insulin resistance, which developed in HFD-fed mice. In in vitro settings PA dose-dependently induced MIF secretion before apoptosis development in islets. Further, mif gene deletion, mRNA silencing or protein inhibition rescued β-cells from PA-induced apoptosis as measured by MTT assay and histone-DNA enzyme linked immuno sorbent assay. Protection from induced apoptosis was mediated by altered activation of caspase pathway and correlated with changes in the level of Bcl-2 family members. Further, MIF inhibition conveyed a significant resistance to PA-induced downregulation of insulin and PDX-1 expression and ATP content. However, β-cell function was not entirely preserved in the absence of MIF judging by low glucose oxidation and depolarized mitochondrial membrane. In conclusion, the observed considerable preservation of β-cells from nutrient-induced apoptosis might implicate MIF as a potential therapeutic target in the later stage of obesity-associated T2D.

Dengue fever is usually a benign acute viral infection transmitted by arthropods but may evolve to severe clinical manifestations such as coagulation and/or hemodynamic disorders, caused mainly by an increase of vascular permeability. Deregulated circulating immunological factors have been associated with severity. In Brazil severe cases appeared in children only recently and we evaluated the profile of cytokine/chemokine kinetics in 134 hospitalized young patients during the epidemic in Rio de Janeiro in 2008. Inflammatory cytokines TNF and IFNγ were found elevated during the acute phase in children as well as the anti-inflammatory IL10 and chemokines MIF and CXCL10/IP10, all last three persisting longer during the recovery phase. Severe disease fitting the dengue hemorrhagic fever pattern (WHO, 1997) was associated with higher IL10 and CXCL10/IP10 circulating levels (peak levels at seven days with P<0.01 and P<0.001 respectively as compared to DF). These factors were higher in patients pulmonary effusion or ascites (P<0.05 for IL10 and P<0.01 for CXCL10/IP10). Both factors were also associated with liver changes such as AST increase correlated with CXCL10/IP10 (r=0.4300 with P<0.0001) and patients presenting painful hepatomegaly showed higher circulating levels of IL10 (P<0.01, at 7-9 days) and of CXCL10/IP10 (P<0.05, 4-6 days and P<0.001, 7-9 days) when compared to patients without apparent liver alterations. Most cases presented a history of prior infection (93%). This is the first study demonstrating cytokine and chemokine association with severity during dengue fever in Brazilian children. IL10 and CXCL10/IP10 play a role in the disease severity associated with induction of vascular leakage and a novel association with changes in liver dysfunction.

Cell death is thought to contribute to progressive renal cell depletion in diabetic nephropathy. Unbiased gene expression profiling identified novel cell death molecules in human diabetic nephropathy. The expression of TNF-related apoptosis-inducing ligand (TRAIL), its decoy receptor osteoprotegerin, and receptors Fas (a Fas ligand receptor) and CD74 (a migration inhibitory factor (MIF) receptor) were induced in human diabetic nephropathy. Cell culture studies supported the functional relevance of this observation and the relationship to a high glucose environment. To define novel proapoptotic proteins upregulated in diabetic nephropathy, functional genomic screens for novel apoptosis mediators were integrated with genome-wide expression profiling and identified candidates for further functional analysis, including brain acid-soluble protein 1 (BASP1). Several lines of evidence point toward induction of endoplasmic reticulum stress response in human diabetic nephropathy. Functional studies defining an unequivocal contribution of endoplasmic reticulum stress to cell death in this setting are still needed. Further comparative studies will be required to define whether there is a specific aspect of apoptosis in progressive human diabetic nephropathy or whether the mechanisms are shared among all patients with chronic kidney disease. The next challenge will be to define the consequence of therapeutic interference of the apoptosis pathways in diabetic nephropathy and chronic kidney disease.