In vitro effects of diacerhein and rhein on interleukin 1 and tumor necrosis factor-alpha systems in human osteoarthritic synovium and chondrocytes

OBJECTIVE: To evaluate the in vitro effects of diacerhein, a new drug for the treatment of osteoarthritis (OA), and its active metabolite, rhein, on interleukin 1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) synthesis and expression in human OA synovial membrane, and on the IL-1beta and TNF-alpha receptors on human OA chondrocytes. METHODS: Levels of IL-1beta and TNF-alpha were determined using specific ELISA in culture medium of human synovial membrane explants incubated in the presence of 1 microg/ml of lipopolysaccharide with or without therapeutic concentrations of diacerhein (1.4, 2.7, 5.4 x 10(-5) M) and rhein (1.7, 3.5, 7.0 x 10(-5) M). IL-1beta mRNA level was quantitated by Northern blotting. Using radioligand binding experiments, we determined the effects of these agents on the density and affinity of chondrocyte IL-1 and TNF receptors. RESULTS: IL-1beta synthesis was significantly inhibited by diacerhein and rhein, with maximum inhibition at 5.4 x 10(-5) M for diacerhein (p < 0.02) and 3.5 x 10(-5) M for rhein (p < 0.05). The effect of both agents on IL-1beta was found to be translational and/or post-translational, judging by the absence of effect on gene expression level. Both agents produced dose and time dependent decreases in the number of IL-1 receptors (IL-1R) on OA chondrocytes. This effect was mediated through a reduction in the level of the type I IL-1R as shown by experiments using a blocking monoclonal antibody against this receptor type. Both agents also markedly reduced the IL-1 induced synthesis and expression of stromelysin 1. Neither diacerhein nor rhein significantly affected the level of synthesis of TNF-alpha or the level of TNF-R. CONCLUSION: Diacerhein and rhein can effectively inhibit the synthesis of IL-1beta on human OA synovium, as well as the action of this cytokine at the cartilage level, by reducing the number of chondrocyte IL-1R. The effects of these agents seemed "selective" to the IL-1 system.     

Tumor necrosis factor-alpha promotes sustained cyclooxygenase-2 expression: attenuation by dexamethasone and NSAIDs

Prostaglandin (PG) release is characteristic of most inflammatory diseases. The committed step in the formation of free arachidonic acid into PG products is catalyzed by cyclooxygenase (COX, prostaglandin H2 synthase, PGHS), which exists as two genetically distinct isoforms. COX-1 is constitutively expressed and produces PGs and thromboxane A2 during normal physiologic activities, while COX-2 is an inducible enzyme stimulated by growth factors, lipopolysaccharide, and cytokines during inflammation or cell injury. Proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) released into the amniotic fluid in the setting of infection have been proposed to signal amnion and decidual cells to produce PGs that may culminate in preterm labor. However, since the molecular control of this phenomenon has not been established, this study used amnion-derived WISH cells to determine if TNF-alpha promoted the formation of PGs through COX-2 activity. Treatment of WISH cells with TNF-alpha (0.1 ng/mL-100 ng/mL) caused a dose-dependent increase in COX-2 expression and the subsequent biosynthesis of PGE2 that persisted for at least 48 hrs. In contrast, COX-1 mRNA and protein levels were unaltered by TNF-alpha treatment as determined by RT-PCR and immunoblot analysis, respectively. TNF-alpha-stimulated COX-2 expression and the subsequent formation of PGE2 were inhibited by dexamethasone (0.1 microM). In addition, indomethacin (1 microM) and the novel COX-2-selective inhibitor, NS-398 (IC50 approximately 1.1 x 10(-9) M), attenuated TNF-alpha-elicited PGE2 production. Results presented here demonstrate that TNF-alpha elicits prolonged and regulatable induction of COX-2 in WISH cells, while COX-1 is constitutively expressed and unchanged in response to TNF-alpha stimulation.     

Auranofin inhibits the induction of interleukin 1 beta and tumor necrosis factor alpha mRNA in macrophages

Gold compounds are widely used in the treatment of rheumatoid arthritis, but their mechanisms of action remain unclear. We demonstrate here that auranofin (AF) (0.1-3 microM), but neither the hydrophilic gold compounds aurothiomalate (ATM) and aurothioglucose nor methotrexate or D-penicillamine, inhibits the induction of interleukin 1 beta and tumor necrosis factor (TNF) alpha mRNA and protein by either zymosan, lipopolysaccharide (LPS), or various bacteria in mouse macrophages. The auranofin-mediated inhibition of the induction of TNF-alpha mRNA was stronger than that of interleukin (IL) 1 beta mRNA. AF, but not the other drugs, also inhibited zymosan-induced mobilization of arachidonate. The fact that AF inhibited the induction of mRNA for both these proinflammatory cytokines, irrespective of which stimulus was used, may indicate that it affects some common signal transduction step vital to their induction.     

Correlations of leucocyte migration activating factor with interleukin-1 alpha, interleukin-1 beta and tumor necrosis factor-alpha in drug allergy

The pathogenic mechanism of drug allergy was investigated by determining leucocyte migration activating factor (LMAF), interleukin-1 alpha (IL 1 alpha) and 1 beta (IL-1 beta), and tumor necrosis factor-alpha (TNF-alpha) levels in 13 patients with suspected hypersensitivity to drugs, following with the relevant agents. LMAF was detected in 10 out of 11 patients in the absence of serum and in 8 out of 9 patients in the presence of serum by means of the leucocyte migration inhibition test (LMIT). The drug-stimulated group had a significantly higher level of IL-1 alpha production than a non-stimulated group, both without serum (p < 0.05) and with serum (p < 0.05), among patients positive for LMAF. Moreover, the LMAF-positive group had a significantly higher level of IL-1 alpha production than the LMIT-negative group, both without serum (p < 0.05) and with serum (p < 0.05). In contrast, the level of IL-1 beta production showed no significant difference, either without or with serum, between drug-stimulated and non-drug-stimulated patients who were positive for LMAF. The production of TNF-alpha in the LMAF-positive group was significantly greater in drug-stimulated patients than in non-drug-stimulated patients, but only in the presence of serum (p < 0.05). However, the level of TNF-alpha production showed no significant difference, either without or with serum, between the LMAF-positive group and the control group. Our findings suggest that IL-1 alpha may be prominently involved in the production of LMAF in allergic reactions to drugs and that the production of TNF-alpha may be enhanced in the presence of serum.     

Regulation of cyclooxygenase-2 and prostaglandin F synthase gene expression by steroid hormones and interferon-tau in bovine endometrial cells

Estradiol (E2) and progesterone are responsible for regulating PG synthesis in the endometrium during the estrous cycle and interferon-tau (IFN-tau) alters PG synthesis during early pregnancy in ruminants. In this study, we examined the effects of these steroid hormones and recombinant bovine IFN-tau (rbIFN-tau) on PG production and on cyclooxygenase-2 (COX-2) and PG F (PGF) synthase (PGFS) gene expression in isolated endometrial cells. E2 decreased both PGF2alpha and PG E2 (PGE2) whereas progesterone increased PGF2alpha secretion in epithelial cells. Steroid hormones had no effect on PG production in stromal cells. rbIFN-tau attenuated both PGF2alpha and PGE2 production in epithelial cells and enhanced their production, and the ratio of PGE2 to PGF2alpha, in stromal cells. Northern blot analysis showed that E2 and rbIFN-tau decreased COX-2 messenger RNA (mRNA) levels in epithelial cells. Conversely, rbIFN-tau increased COX-2 mRNA in stromal cells. Furthermore, rbIFN-tau decreased PGFS mRNA in both cell types and this was associated with the increase in PGE2/PGF2alpha ratio. These results show that the regulation of PG synthesis by steroid hormones is different in endometrial epithelial and stromal cells in vitro. The attenuation of PGF2alpha secretion from epithelial cells and increased PGE2 production in stromal cells by rbIFN-tau are modulated by steroid hormones.     

Selective induction of tumor necrosis factor receptor type II gene expression by tumor necrosis factor-alpha in C6 glioma cells

The aim of this study, in rabbit tibia, was an evaluation of the early reactions of the tissues to the insertion of polylactic membranes, used in connection with titanium implants. The specimens were retrieved after 1-4 weeks, and a histological analysis was performed. It was possible to see that, in the early implantation phases, no degradation of the macrostructure of the membrane was present. On the outer portion of the membrane many multinucleated giant cells (MGC) were present and membrane fragments were present inside the cytoplasm of these cells. These cells could explain the inflammatory processes reported, in some reports, with the use of materials made by polylactic and polyglycolic acid. We did not observe detrimental effects in the bone tissue around the membrane, and the membrane appeared to have a mechanical stability for the time necessary for bone regeneration.     

Differential effects of interleukin 1-alpha (IL-1 alpha) or tumor necrosis factor-alpha (TNF-alpha) on motility of human melanoma cell lines on fibronectin

Interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor-alpha (TNF-alpha) induce a motogenic response in a number of benign and malignant cells. We examined the chemokinetic effects of these cytokines on the cell migration of four melanoma cell lines on fibronectin using modified Boyden chambers and video-time lapse analysis. Flow cytometry analysis of IL-1 receptors, TNF receptors, and shifts in beta 1 integrin expression were correlated with the effects of these cytokines on cell migration on fibronectin. The four melanoma cell lines exhibited heterogeneous expression of types I and II IL-1 receptors as well as p60 TNF receptors. Scant p80 TNF receptor expression was detected on only one cell line. Three of four melanoma cell lines demonstrated type I IL-1 receptors by Western blotting. IL-1 alpha and TNF-alpha induced heterogeneous modulation of beta 1 integrin expression in the four melanoma cell lines tested; downward shift of the alpha 2, alpha 3, alpha 4, and beta 1 integrin subunits was detected among three of the melanoma cell lines as were upward shifts of the alpha 4, alpha 5, and alpha 6 integrin subunits among three of the melanoma cell lines. IL-1 alpha and TNF-alpha induced enhanced migration on fibronectin in one of the melanoma cell lines and were related to an upward shift in the alpha 4 and alpha 5 integrin subunit expression. Taken together, the findings indicate that expression of a particular receptor for IL-1 or TNF does not necessarily signal a motogenic response in melanoma cells, but induces heterogeneous shifts in beta 1 integrin expression. However, upregulation in alpha 4 and alpha 5 integrin subunits appears to relate to enhanced migration on fibronectin.     

Antitumor activity of recombinant human tumor necrosis factor-alpha (rH-TNF alpha) and liposome-entrapped rH-TNF alpha

The antitumor activities of recombinant human tumor necrosis factor-alpha (rH-TNF alpha) and liposome-entrapped rH-TNF alpha were evaluated in various glioma cell lines and a rat brain T9 gliosarcoma model. rH-TNF alpha had a direct cytotoxic activity against various glioma cell lines in vitro, and indirect cytotoxic activity against gliosarcoma (T9) in vivo. Liposome-entrapped rH-TNF alpha had increased direct cytotoxic activity in vitro, and against experimentally induced brain tumors in vivo. The effects in vivo were probably due to vascular damage of the tumor vessels as shown by histological examination and activation of cytotoxic macrophages as shown in vitro. These results indicate that the general or local administration of liposome-entrapped rH-TNF alpha may become a useful adjunct treatment for malignant brain tumor.     

Interleukin 1beta and interleukin 6, but not tumor necrosis factor alpha, inhibit insulin-stimulated glycogen synthesis in rat hepatocytes

Recent evidence indicates that inflammatory cytokines are involved in changes of blood glucose concentrations and hepatic glucose metabolism in infectious diseases, including sepsis. However, little is known regarding how cytokines interact with glucoregulatory hormones such as insulin. The objective of the present study is to investigate if and how cytokines influence insulin-stimulated glycogen metabolism in the liver. Interleukin 1beta (IL-1beta) and interleukin 6 (IL-6) markedly inhibited the increase of glycogen deposition stimulated by insulin in primary rat hepatocyte cultures; however, tumor necrosis factor alpha had no effect. Labeling experiments revealed that both cytokines counteracted insulin action by decreasing [14C]-glucose incorporation into glycogen and by increasing [14C]-glycogen degradation. Furthermore, it was discovered that IL-1beta and IL-6 inhibited glycogen synthase activity and, in contrast, accelerated glycogen phosphorylase activity. In experiments with kinase inhibitors, serine/threonine kinase inhibitor K252a blocked IL-1beta- and IL-6-induced inhibitions of glycogen deposition, as well as glycogen synthase activity, whereas another kinase inhibitor staurosporine blocked only IL-6-induced inhibition. Tyrosine kinase inhibitor herbimycin A blocked only IL-1beta-induced inhibition. These results indicate that IL-1beta and IL-6 regulate insulin-stimulated glycogen synthesis through different pathways involving protein phosphorylation in hepatocytes. They may mediate the change of hepatic glucose metabolism under pathological and even physiological conditions by modifying insulin action in vivo.     

Interferon-gamma potentiates interleukin (IL)-6 and tumor necrosis factor-alpha but not IL-1beta induced by endotoxin in the brain

Because interferon-gamma (IFN gamma) is present in the central nervous system during neurologic diseases associated with inflammation, its effect on endotoxin-induced cytokines was studied. Cerebrospinal fluid (CSF) and serum levels of interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha (TNF alpha), their messenger RNA expression in brain areas (hypothalamus, hippocampus, and striatum) and in spleen were evaluated 2 and 8 h after endotoxin [lipopolysaccharide (LPS), 25 microg/rat i.c.v.], IFN gamma (2.5 microg/rat i.c.v.) or after their coadministration in rats. CSF and serum IL-1beta levels were increased by LPS alone and IFN gamma coadministration did not furtherly increase them. IFN gamma potentiated LPS effect on IL-6 and TNF alpha levels in both CSF and serum. LPS and IFN-gamma coadministration did not alter IL-1beta messenger RNA expression induced by LPS in brain areas and in spleen, but it potentiated that of IL-6 and TNF alpha. The present in vivo data show that i.c.v. coadministration of LPS and IFN gamma results in a potentiation of cytokine production (IL-6 and TNF alpha) which may trigger a cascade of events relevant to neurodegenerative processes. This action is independent of IL-1beta because the production of this cytokine is not altered by IFN gamma treatment.     

Suppressive effect of ethanol on the expression of hepatic asialoglycoprotein receptors augmented by interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha

Blood levels of inflammatory-related cytokines, including interleukin (IL)-1beta, IL-6, and tumor necrosis factor (TNF)-alpha, are elevated in patients with alcoholic liver diseases. We investigated the effects of these cytokines and ethanol on the expression of hepatic asialoglycoprotein receptors (AGPRs) in a human hepatoblastoma cell line, HepG2. An [125I]-asialo-orosomucoid binding assay showed significant increases in surface AGPR numbers in HepG2 cells by treatment with IL-1beta, IL-6, and TNF-alpha, to levels which were approximately 130% of the values in untreated control cells. However, the enhanced AGPR numbers induced by treatment with these cytokines were markedly suppressed, to 70%-80% of the number in the untreated cells, by treatment with ethanol. Immunological detection of AGPR with a specific antibody demonstrated that the modulation of surface AGPR numbers was correlated with the cellular expression levels of AGPR. These results suggest that, although IL-1beta, IL-6, and TNF-alpha stimulate the synthesis of hepatic AGPR, ethanol suppresses the expression of AGPR augmented by these cytokines. This leads to an increase in serum asialo-orosomucoid levels caused by the disordered catabolism mediated by AGPR in patients with alcoholic liver disease.     

Levels of inhibitors of tumor necrosis factor alpha and interleukin 1beta in urine and sera of patients with urosepsis

The antiinflammatory cytokine response during urosepsis was determined by measurement of concentrations of soluble tumor necrosis factor receptor (sTNFR) types I and II, interleukin 1 receptor antagonist (IL-1ra), soluble IL-1 receptor type II (sIL-1RII), and interleukin 10 in sera and urine of 30 patients with culture-proven urinary tract infections before and 4, 24, 48, and 72 h after initiation of antibiotic therapy and in 20 healthy individuals. In serum, the levels of sTNFR types I and II, IL-1ra, and IL-10 were higher in patients than in controls. In urine, only sTNFR type I and II levels were elevated in patients. The ratios of concentrations of both types of sTNFR in urine to concentrations in serum were higher in patients than in controls. These findings indicate that during urosepsis, the antiinflammatory cytokine response is generated predominantly at the systemic level.     

The association of peripheral monocyte derived interleukin 1beta (IL-1beta), IL-1 receptor antagonist, and tumor necrosis factor-alpha with osteoarthritis in the elderly

OBJECTIVE: To examine the association of peripheral blood mononuclear cell (PBMC) derived interleukin 1beta (IL-1beta), IL-1 receptor antagonist (IL-1Ra), tumor necrosis factor alpha (TNF-alpha), and radiographic osteoarthritis (OA) in the elderly. METHODS: A total of 703 subjects (436 women, 267 men, mean age 78.5+/-4.5 yrs) had both knee and hand radiographs, and cytokines were measured during the 22nd biennial examination of the Framingham Cohort. PBMC derived IL-1beta , IL-1Ra, and TNF-alpha production was assessed using a non-cross reacting polyclonal radioimmunoassay. Knee OA was defined as a score of > 2 using a modified Kellgren and Lawrence scale. The presence of osteophytes and joint space narrowing were scored separately on a 0-3 scale, in which disease was defined a priori as a score > 0 for each feature. Sex-specific odds ratios were calculated for knee OA after adjusting for weight, history of knee injury, and use of estrogen and nonsteroidal antiinflammatory drugs. RESULT: No uniform associations were found for IL-1beta or IL-1Ra in men, or for TNF-alpha production and radiographic OA in either sex. We found possible associations for the highest levels of IL-1beta production and the presence of knee osteophytes [OR=2.0 (1.2-3.5)] and joint space narrowing [OR=1.7 (1.1-2.8)] in women. Our data suggested a possible protective effect for IL-1Ra production and hand OA in women [OR=0.6 (0.4-1.0)]. CONCLUSION: We found no consistent association of PBMC cytokine production and radiographic OA. However, women with the highest production of IL-1beta and IL-1Ra had respectively higher rates of knee OA and lower rates of hand OA than expected.     

Tumour necrosis factor alpha and interleukin 1beta in relapse of Crohn's disease

BACKGROUND: Concentrations of proinflammatory cytokines are increased in the intestinal mucosa of patients with active Crohn's disease. Experimental immunotherapeutic interventions with anticytokine agents in refractory Crohn's disease show that tumour necrosis factor alpha (TNF alpha) may be an important mediator of inflammation. We investigated the relation between production of TNF alpha and interleukin 1beta by mononuclear cells of the colonic lamina propria in patients with remitting Crohn's disease and the risk of relapse. METHODS: We followed up 137 patients with Crohn's disease in steroid-induced remission for 1 year. Secretion of proinflammatory cytokines (tumour necrosis factor alpha [TNF alpha] and interleukin 1beta) was assessed after short-term culture of human lamina propria mononuclear cells. FINDINGS: Increased secretion of TNF alpha and interleukin 1beta were predictive for acute relapses within the next year. Site and extent of disease, baseline demographics, and serum acute-phase proteins had little predictive value. INTERPRETATION: TNF alpha is important as a target molecule for immune interventions in Crohn's disease. The capacity to produce TNF alpha or interleukin 1beta may identify patients who would benefit from anti-inflammatory remission maintenance.