TNF-mediated IL6 gene expression and cytotoxicity are co-inducible in TNF-resistant L929 cells

C-reactive protein serum level in patients with psoriasis before and after treatment with narrow-band ultraviolet B

Background:

C-reactive protein is an inflammatory biomarker and its level increases in the serum of psoriatic patients. Its level is also associated with Psoriasis Area and Severity Index score.

Objective:

The aim of this study was to assess the decrement of serum C-reactive protein level with narrow-band ultraviolet B (NB-UVB) therapy.

Methods:

C-reactive protein serum levels in psoriasis patients were measured before and after treatment with NB-UVB and the data were analyzed in relation to the Psoriasis Area and Severity Index score improvement.

Results:

Baseline C-reactive protein levels among psoriatic patients were higher than normal. These levels decreased significantly after treatment (P<0.001). At the beginning of the study, patients with higher levels of C-reactive protein also had more extensive and severe skin involvement. The highest decrease in C-reactive protein was observed in patients who responded better to the treatment and achieved a higher Psoriasis Area and Severity Index 75%. There was an association between baseline Psoriasis Area and Severity Index scores and C-reactive protein levels.

Conclusion:

Patients with moderate to severe plaque-type psoriasis had active systemic inflammation, which was demonstrated by increased levels of C-reactive protein. Furthermore, skin disease severity was correlated with C-reactive protein levels. Phototherapy healed the psoriatic skin lesions and reduced inflammation, while decreasing C-reactive protein levels.

Effects of lithium on inflammation

Lithium is an effective medication for the treatment of bipolar affective disorder. Accumulating evidence suggests that inflammation plays a role in the pathogenesis of bipolar disorder and that lithium has anti-inflammatory effects that may contribute to its therapeutic efficacy. This article summarizes the studies which examined the effects of lithium on pro- and anti-inflammatory mediators. Some of the summarized data suggest that lithium exerts anti-inflammatory effects (e.g., suppression of cyclooxygenase-2 expression, inhibition of interleukin (IL)-1β and tumor necrosis factor-α production, and enhancement of IL-2 and IL-10 synthesis). Nevertheless, there is a large body of data which indicates that under certain experimental conditions lithium also exhibits pro-inflammatory properties (e.g., induction of IL-4, IL-6 and other pro-inflammatory cytokines synthesis). The reviewed studies utilized various experimental model systems, and it is thus difficult to draw an unequivocal conclusion regarding the effect of lithium on specific inflammatory mediators.

Molecular cloning, expression and regulation analysis of the interleukin-6 (IL-6) gene in goose adipocytes

1. Interleukin-6 (IL-6) is a multifunctional cytokine involved in lipid metabolism in adipose tissue. The objective of the study was to identify and characterize the IL-6 gene in the goose. 2. A full-length coding sequence (CDS) of the goose (Anser anser) IL-6 gene was cloned that encoded a 234-amino acid peptide containing a 38-amino acid signal peptide, an IL-6/G-CSF/MGF family consensus pattern and four conserved α-helices. The mature goose IL-6 showed 74% and 39% identities to that of chicken and human, respectively. 3. Quantitative real-time PCR analysis showed that the goose IL-6 was predominantly expressed in liver and was up-regulated in adipocytes by lipopolysaccharide (LPS) and oleic acid.

Effects of etanercept on C-reactive protein levels in psoriasis and psoriatic arthritis

BACKGROUND

C-reactive protein (CRP), an inflammation biomarker, indicates cardiovascular risk and is elevated in psoriasis. The effect of etanercept on CRP in psoriasis has not been previously examined.

OBJECTIVES

The primary objective was to examine the effect of etanercept on CRP levels from baseline to week 12 compared with placebo. Secondary objectives included assessment of baseline CRP and relationships between CRP and body mass index (BMI), statin drug use, and Psoriasis Area and Severity Index (PASI) scores.

METHODS

A retrospective analysis was conducted of CRP levels from patients with psoriasis who participated in a randomized, double-blind, placebo-controlled, U.S. registrational study. Data were analysed separately if patients self-reported psoriatic arthritis.

RESULTS

Baseline CRP levels were elevated in patients with psoriasis with and without psoriatic arthritis. CRP was significantly reduced in both groups after 12 weeks of etanercept treatment. Patients with psoriasis with psoriatic arthritis and patients with higher BMIs had higher median baseline CRP values and greater reduction of CRP values compared with those without psoriatic arthritis and those with lower BMIs. Etanercept lowered CRP levels in statin users and nonusers. Regression analyses revealed an association between baseline PASI score and baseline CRP independent of BMI in patients with psoriasis.

CONCLUSIONS

Patients with moderate to severe plaque psoriasis, with or without psoriatic arthritis, have increased systemic inflammation demonstrated by elevated CRP levels. In psoriasis without psoriatic arthritis, skin disease activity is associated significantly with CRP elevation, independent of BMI, age and sex. Etanercept reduced CRP levels in all but the normal weight psoriasis group without psoriatic arthritis.

Role of FAN in tumor necrosis factor-alpha and lipopolysaccharide-induced interleukin-6 secretion and lethality in D-galactosamine-sensitized mice

Tumor necrosis factor (TNF) alpha-induced neutral sphingomyelinase-mediated generation of ceramide, a bioactive lipid molecule, is transduced by the adaptor protein FAN, which binds to the intracellular region of the CD120a TNFalpha receptor. FAN-deficient mice do not exhibit any gross abnormality. To further explore the functions of FAN in vivo and because CD120a-deficient mice are resistant to endotoxin-induced liver failure and lethality, we investigated the susceptibility of FAN-deficient animals to lipopolysaccharide (LPS). We show that after d-galactosamine sensitization, FAN-deficient mice were partially resistant to LPS- and TNFalpha-induced lethality. Although LPS challenge resulted in a hepatic ceramide content lower in mutant mice than in control animals, it triggered similar histological alterations, caspase activation, and DNA fragmentation in the liver. Interestingly, LPS-induced elevation of IL-6 (but not TNFalpha) serum concentrations was attenuated in FAN-deficient mice. A less pronounced secretion of IL-6 was also observed after LPS or TNFalpha treatment of cultured peritoneal macrophages and embryonic fibroblasts isolated from FAN-deficient mice, as well as in human fibroblasts expressing a mutated FAN. Finally, we show that d-galactosamine-sensitized IL-6-deficient mice were partially resistant to endotoxin-induced liver apoptosis and lethality. These findings highlight the role of FAN and IL-6 in the inflammatory response initiated by endotoxin, implicating TNFalpha.

Enhanced phosphorylation of nuclear 21-kDa and 34-kDa proteins in hepatoma cell death induced by tumor-necrosis factor-alpha

The role of nuclear protein phosphorylation in intracellular signal transduction of tumor-necrosis factor-alpha (TNF-alpha) in the human hepatoma cell line PLC(PRF/5) was investigated. TNF-alpha, which displays cytolytic activity against PLC hepatoma cells, elevated the in vitro phosphorylation of two nuclear proteins (21 kDa and 34 kDa) 16 h after treatment. The cytotoxicity and enhanced nuclear protein phosphorylation by TNF-alpha treatment decreased in the presence of dexamethasone. Both the 21-kDa and 34-kDa proteins were extracted with 2.2 M NaCl from nuclear pellets and phosphorylated in kinase reaction mixtures containing a high concentration of salt. By phosphoamino acid analysis, the specificity of the nuclear kinase was found to be directed toward serine residues. The protein kinase inhibitors H7, staurosporine and herbimycin A, inhibited the phosphorylation of the 21-kDa and 34-kDa proteins in vitro, but calphostin C and heparin did not. The treatment of cells with 4 beta-phorbol 12-myristate 13-acetate or okadaic acid did not affect the in vitro phosphorylation of the two nuclear proteins. An anti-Fas antibody increased the phosphorylation of the 21-kDa and 34-kDa proteins in PLC cells. DNA fragmentation was observed in PLC cells treated with TNF-alpha and anti-Fas antibody after 24 h treatment. These data suggest an involvement of nuclear protein kinase in signal-transduction pathways of apoptotic cell damage triggered by TNF-alpha in PLC hepatoma cells.

Activation of the nuclear factor kappa B is not sufficient for regulation of tumor necrosis factor-induced interleukin-6 gene expression

After treatment of L929 cells, a murine fibrosarcoma line, with tumor necrosis factor (TNF), a nuclear kappa B-like transcription factor is rapidly induced as identified by gel shift mobility assays using the kappa B-responsive sequence of the immunoglobulin or interleukin-6 (IL-6) genes as a DNA probe. When induction was carried out under conditions of increased or decreased cytotoxicity, which correlates with altered IL-6 gene expression, nuclear factor kappa B (NF-kappa B) activation was also demonstrated, but the abundance of the protein/DNA complex observed remained unchanged. Also activation of NF-kappa B as a function of time following TNF treatment did not reveal a correlation between the abundance of the protein/DNA complex and the TNF-induced IL-6 mRNA levels. Moreover, in L929 cells resistant to TNF cytotoxicity, the kappa B-like factor still became fully activated by TNF, although the IL-6 gene was only marginally expressed. In conclusion, discrepancies between the abundance of the activated NF-kappa B-like factor and the IL-6 mRNA production upon treatment with TNF indicate that (an) additional transcription factor(s) and/or (a) regulating mechanism(s) is (are) necessary for fine regulation of the level of IL-6 gene expression in response to cytokine stimulation.

Tumor necrosis factor activities and cancer therapy--a perspective

Tumor necrosis factor (TNF) is a multifunctional cytokine which has excited and fascinated numerous investigators and commercial entities due to its promise as a therapeutic agent against cancer and as a target for drugs treating septic shock. TNF is a protein having cytotoxic, cytostatic, immunomodulatory as well as several other activities and is also involved in septic shock. This review covers the structure of TNF and its receptors, various in vitro activities and in vivo activities based on studies in animal model systems. The role of TNF as an anticancer therapeutic agent, based on various phase I and phase II clinical studies, has also been considered. The review concludes with several considerations for increasing the therapeutic utility of TNF in terms of targeting, toxicity and half-life.