scholarly journals Inhibition of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) messenger RNA (mRNA) expression in HL-60 leukemia cells by pentoxifylline and dexamethasone: dissociation of acivicin- induced TNF-alpha and IL-1 beta mRNA expression from acivicin-induced monocytoid differentiation

Blood ◽  
1992 ◽  
Vol 79 (12) ◽  
pp. 3337-3343 ◽  
Author(s):  
JB Weinberg ◽  
SN Mason ◽  
TS Wortham

Abstract We have previously noted that the glutamine antagonist acivicin (alpha S,5S-alpha-amino-3-chloro-4,5-dihydro-5-isoxazoleacetic acid) induces monocytoid differentiation of freshly isolated human myeloid leukemia cells and cells of the myeloid leukemia cell line HL-60, and that the differentiation is accompanied by increases in expression of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta). Because we also showed that TNF-alpha and IL-1 beta can act synergistically to cause monocytoid differentiation of HL-60 cells, we hypothesized that acivicin-induced TNF-alpha and IL-1 beta, in an autocrine manner, caused the differentiation. The purpose of the present study was to determine the causal roles of TNF-alpha and IL-1 beta in the acivicin-induced differentiation of HL-60 cells by the use of dexamethasone (DEX) and pentoxifylline (PTX), two drugs that effectively inhibit expression of TNF-alpha and IL-1 beta. Acivicin caused a monocytoid differentiation of the cells as manifest by diminished cell growth, morphologic maturation of the cells, increased ability to generate hydrogen peroxide in response to acute treatment with phorbol myristate acetate, and increased expression of nonspecific esterase and the surface antigens CD14 and CD11b. Acivicin treatment also caused the cells to have diminished steady-state expression of messenger RNA (mRNA) for c-myc and c-myb, and increased expression of mRNA for TNF-alpha and IL-1 beta. DEX and PTX did not alter cell growth, and did not block the acivicin-induced block in growth. PTX caused a slight increase in nonspecific esterase expression, but DEX had no effect on this, and neither drug diminished the acivicin-induced increase in nonspecific esterase. Although neither drug alone lessened the acivicin enhancement of hydrogen peroxide production, DEX and PTX together reduced this. DEX did not modify the acivicin-induced morphologic maturation of the cells, but PTX alone or PTX with DEX potentiated the acivicin-induced increase in mature cells. Basal CD14 and CD11b expression were slightly reduced by DEX and PTX, but neither drug modified the acivicin-induced increases. DEX and PTX reduced the acivicin-induced increases in TNF-alpha and IL-1 beta mRNA expression, but they had little or no effect on the acivicin-induced decreases in expression of mRNA for c-myc and c-myb. Thus, DEX and PTX effectively block the acivicin-induced expression of TNF-alpha and IL-1 beta, but they have little influence on the acivicin-induced differentiation process.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood ◽  
1992 ◽  
Vol 79 (12) ◽  
pp. 3337-3343 ◽  
Author(s):  
JB Weinberg ◽  
SN Mason ◽  
TS Wortham

We have previously noted that the glutamine antagonist acivicin (alpha S,5S-alpha-amino-3-chloro-4,5-dihydro-5-isoxazoleacetic acid) induces monocytoid differentiation of freshly isolated human myeloid leukemia cells and cells of the myeloid leukemia cell line HL-60, and that the differentiation is accompanied by increases in expression of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta). Because we also showed that TNF-alpha and IL-1 beta can act synergistically to cause monocytoid differentiation of HL-60 cells, we hypothesized that acivicin-induced TNF-alpha and IL-1 beta, in an autocrine manner, caused the differentiation. The purpose of the present study was to determine the causal roles of TNF-alpha and IL-1 beta in the acivicin-induced differentiation of HL-60 cells by the use of dexamethasone (DEX) and pentoxifylline (PTX), two drugs that effectively inhibit expression of TNF-alpha and IL-1 beta. Acivicin caused a monocytoid differentiation of the cells as manifest by diminished cell growth, morphologic maturation of the cells, increased ability to generate hydrogen peroxide in response to acute treatment with phorbol myristate acetate, and increased expression of nonspecific esterase and the surface antigens CD14 and CD11b. Acivicin treatment also caused the cells to have diminished steady-state expression of messenger RNA (mRNA) for c-myc and c-myb, and increased expression of mRNA for TNF-alpha and IL-1 beta. DEX and PTX did not alter cell growth, and did not block the acivicin-induced block in growth. PTX caused a slight increase in nonspecific esterase expression, but DEX had no effect on this, and neither drug diminished the acivicin-induced increase in nonspecific esterase. Although neither drug alone lessened the acivicin enhancement of hydrogen peroxide production, DEX and PTX together reduced this. DEX did not modify the acivicin-induced morphologic maturation of the cells, but PTX alone or PTX with DEX potentiated the acivicin-induced increase in mature cells. Basal CD14 and CD11b expression were slightly reduced by DEX and PTX, but neither drug modified the acivicin-induced increases. DEX and PTX reduced the acivicin-induced increases in TNF-alpha and IL-1 beta mRNA expression, but they had little or no effect on the acivicin-induced decreases in expression of mRNA for c-myc and c-myb. Thus, DEX and PTX effectively block the acivicin-induced expression of TNF-alpha and IL-1 beta, but they have little influence on the acivicin-induced differentiation process.(ABSTRACT TRUNCATED AT 250 WORDS)


1991 ◽  
Vol 261 (4) ◽  
pp. L315-L321 ◽  
Author(s):  
J. N. Allen ◽  
D. J. Herzyk ◽  
M. D. Wewers

To study the role of microtubules in cytokine production, the effect of the microtubule depolymerizing agent colchicine on lipopolysaccharide endotoxin (LPS)-induced interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) release by blood monocytes and alveolar macrophages were examined. Immunofluorescence microscopy demonstrated that LPS resulted in the appearance of microtubule-containing cytoplasmic appendages and that colchicine, which resulted in microtubule disruption in monocytes, blocked appendage formation. Colchicine resulted in approximately 50% increase in LPS-induced IL-1 beta release and a 50% decrease in LPS-induced TNF-alpha release by human monocytes at all doses of LPS tested. Although colchicine resulted in a statistically significant increase in LPS-stimulated human alveolar macrophage IL-1 beta release, the increase was not as great as that observed with monocytes. Northern blot analysis suggested that the colchicine effect occurs pretranslationally because colchicine caused an increase in LPS-stimulated IL-1 beta mRNA levels and a decrease in TNF-alpha mRNA levels. These results suggest that microtubules contribute to the regulation of endotoxin-stimulated mononuclear phagocyte cytokine production and that this regulation differs significantly between IL-1 beta and TNF-alpha.


1991 ◽  
Vol 261 (5) ◽  
pp. F792-F798 ◽  
Author(s):  
P. Steiner ◽  
J. Pfeilschifter ◽  
C. Boeckh ◽  
H. Radeke ◽  
U. Otten

Recent evidence indicates that cytokines are potent inducers of nerve growth factor (NGF) expression both in peripheral tissues and the central nervous system and that NGF, in addition to its neurotrophic action, also acts as an immunoregulatory agent. It was of interest to investigate whether inflammatory cytokines affect NGF production in renal mesangial cells, which play a crucial role in the modulation of the local immune function in the glomerulus. Our results show that the simultaneous addition of interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) elicited a marked (13-fold) increase of NGF protein released by cultured rat glomerular mesangial cells within 24 h, whereas IL-1 alpha in combination with TNF-alpha, as well as the cytokines alone, did not promote the synthesis of NGF. The synergistic effect was dose dependent (maximal at 1 nM) and due to enhanced gene expression, since the cytokine treatment caused a fivefold increase in NGF mRNA after 8 h. Stimulation of NGF synthesis was abolished by mepacrine and dexamethasone, indicating that phospholipase A2 may be involved in NGF regulation. Moreover, pretreatment of the cells with the lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA) abolished induction of NGF by cytokines; in contrast, the specific cyclooxygenase inhibitors indomethacin and diclofenac failed to modify NGF production. These data suggest that a lipoxygenase metabolite produced in response to IL-1 beta and TNF-alpha acts as a mediator in NGF gene expression. In conclusion, these findings support a model in which a cytokine cascade including NGF may play an important role in the pathophysiology of inflammatory renal diseases.


1991 ◽  
Vol 174 (6) ◽  
pp. 1355-1362 ◽  
Author(s):  
A Walz ◽  
R Burgener ◽  
B Car ◽  
M Baggiolini ◽  
S L Kunkel ◽  
...  

A new neutrophil-activating peptide, termed ENA-78, was identified in the conditioned media of stimulated human type II epithelial cell line A549. In response to stimulation with either interleukin 1 beta (IL-1 beta) or tumor necrosis factor alpha (TNF-alpha), ENA-78 was produced and secreted concomitantly with IL-8, GRO alpha, and GRO gamma. ENA-78 consists of 78 amino acids [sequence; see text] and has a molecular weight of 8,357. It has four cysteines positioned identically to those of IL-8 and analogues, and thus belongs to the CXC family of peptides. ENA-78 is related to neutrophil-activating peptide 2 (NAP-2) and GRO alpha (sequence identity, 53% and 52%, respectively) and IL-8 (22% identity). Like NAP-2 and GRO alpha, ENA-78 stimulates neutrophils, inducing chemotaxis, a rise in intracellular free calcium and exocytosis. Cross-desensitization experiments indicate that ENA-78 acts through the same type of receptors as IL-8, NAP-2, and GRO alpha.


1994 ◽  
Vol 266 (4) ◽  
pp. R1197-R1203 ◽  
Author(s):  
D. Beasley ◽  
M. Eldridge

Cytokine-inducible nitric oxide (NO) production has been implicated in the pathogenesis of septic shock. The present study was designed to determine which cytokines induce expression of the NO synthase gene in rat aortic vascular smooth muscle cells (VSMC) in vitro and whether NO synthase gene expression is inducible in vivo. NO synthase mRNA appeared after 4-h exposure to interleukin-1 beta (IL-1 beta), and levels continued to increase up to 24 h. Levels of NO synthase transcripts were greatest in VSMC treated with IL-1 beta (1 nM), lower in VSMC treated with Escherichia coli lipopolysaccharide (LPS; 100 micrograms/ml), and just detectable in VSMC treated with tumor necrosis factor-alpha (TNF-alpha; 1 nM). IL-1 beta, TNF-alpha, and LPS each induced NO synthase activity, assessed by release of nitrite, conversion of L-arginine to L-citrulline, and increased levels of guanosine 3',5'-cyclic monophosphate, whereas IL-2, IL-6, and interferon-gamma were ineffective. IL-1 beta was more potent and effective than TNF-alpha; however, submaximal concentrations of TNF-alpha acted synergistically with IL-1 beta to induce NO synthase gene expression and activity. Inducible NO synthase mRNA was present in aorta from rats 6 h after treatment with LPS (5 mg/kg), but not at 24 h. Synergistic activation of NO synthase gene expression in VSMC by IL-1 beta and TNF-alpha may contribute to hypotension in sepsis.


1990 ◽  
Vol 172 (2) ◽  
pp. 497-507 ◽  
Author(s):  
O Ramilo ◽  
X Sáez-Llorens ◽  
J Mertsola ◽  
H Jafari ◽  
K D Olsen ◽  
...  

Although previous studies using human cytokines in rabbits and rats have provided evidence of the participation of tumor necrosis factor alpha (TNF-alpha) and interleukin 1 beta (IL-1 beta) in the meningeal inflammatory cascade, the results obtained by several groups of investigators have been discordant or, at times, contradictory. In the present study, homologous cytokines were applied to the rabbit meningitis model. Intracisternal administration of 10(2)-10(5) IU of purified rabbit TNF-alpha (RaTNF-alpha) produced significant cerebrospinal fluid (CSF) inflammation. A similar response was observed after intracisternal inoculation of 5-200 ng of rabbit recombinant IL-1 beta (rrIL-1 beta). Preincubation of these two mediators with their specific antibodies resulted in an almost complete suppression of the CSF inflammatory response. In animals with Haemophilus influenzae type b lipooligosaccharide-induced meningitis, intracisternal administration of anti-rrIL-1 beta, anti-RaTNF-alpha, or both resulted in a significant modulation of meningeal inflammation. Simultaneous administration of 10(3) IU of RaTNF-alpha and 5 ng of rrIL-1 beta resulted in a synergistic inflammatory response manifested by a more rapid and significantly increased influx of white blood cells into the CSF compared with results after each cytokine given alone. These data provide evidence for a seminal role of TNF-alpha and IL-1 beta in the initial events of meningeal inflammation.


1991 ◽  
Vol 261 (5) ◽  
pp. R1096-R1103 ◽  
Author(s):  
M. Shibata ◽  
C. M. Blatteis

This study was undertaken to determine whether the reported different courses of the febrile responses to the cytokines interleukin-1 beta (IL-1), interferon-alpha 2 (IFN), and tumor necrosis factor-alpha (TNF) might have neuroelectrophysiological correlates. The reactions of individual thermosensitive neurons in the preoptic area (POA) were evaluated by recording their extracellular single-unit firing rates (FR) in slices of guinea pig POA perfused with artificial cerebrospinal fluid (aCSF), human recombinant IL-1 (50-500 ng), IFN (1,000-8,000 U), and TNF (400-5,000 ng) (all doses per min/ml aCSF); thermosensitivity was assessed by FR responses to changes of perfusate temperature (32-42 degrees C). Overall, these cytokines depressed the FR of warm-sensitive units and excited those of cold-sensitive units, in agreement with expectations. However, the responses of individual neurons treated with two or all three cytokines were dissimilar: 61% of the units tested reacted differentially to two or three cytokines, 32% exhibited identical responses, and 7% had no response to any cytokine. These results support the possibility that IL-1, IFN, and TNF may affect not the same but rather distinct neurons functionally connected to common pyrogenic effectors. Thus they suggest that differential neuronal substrates may be utilized by each cytokine to exert its pyrogenic effect.


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