Action Of Interleukin-1 Beta Research Articles

Effectiveness of NLRP3 Inhibitor as a Non-Hormonal Treatment for ovarian endometriosis

BackgroundEndometriosis is a complex syndrome characterized by an estrogen-dependent chronic inflammatory process that affects 10% of women of reproductive age. Ovarian endometriosis (OE) is the most common lesion in endometriosis and may cause infertility, in addition to dysmenorrhea. Hormonal treatments, which are the conventional treatment methods for endometriosis, suppress ovulation and hence are not compatible with fertility. The inflammasome is a complex that includes Nod-like receptor (NLR) family proteins, which sense pathogen-associated molecular patterns and homeostasis-altering molecular processes. It has been reported that the nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain-containing (NLRP) 3 inflammasome, which contributes to the activation of interleukin-1 beta (IL-1β), might be related to the progression of endometriosis. Therefore, the aim of the present study was to evaluate non-hormonal therapies for OE, such as inhibitors of the NLRP3 inflammasome.MethodsThe expression of NLRP3 was measured in the eutopic endometrium (EM) of patients with and without endometriosis and OE samples, as well as stromal cells derived from the endometrium of patients with and without endometriosis and OE samples (endometrial stromal cells with endometriosis [ESCs] and cyst-derived stromal cells [CSCs]). The effects of an NLRP3 inhibitor (MCC950) on ESCs and CSCs survival and IL-1β production were evaluated. We then administered MCC950 to a murine model of OE to evaluate its effects on OE lesions and ovarian function.ResultsNLRP3 gene and protein expression levels were higher in OE and CSCs than in EM and ESCs, respectively. MCC950 treatment significantly reduced the survival of CSCs, but not that of ESCs. Moreover, MCC950 treatment reduced the co-localization of NLRP3 and IL-1β in CSCs, as well as IL-1β concentrations in CSCs supernatants. In the murine model, MCC950 treatment reduced OE lesion size compared to phosphate-buffered saline treatment (89 ± 15 vs. 49 ± 9.3 mm3 per ovary; P < 0.05). In the MCC950-treated group, IL-1β and Ki67 levels in the OE-associated epithelia were reduced along with the oxidative stress markers of granulosa cells.ConclusionsThese results indicated that NLRP3/IL-1β is involved in the pathogenesis of endometriosis and that NLRP3 inhibitors may be useful for suppressing OE and improving the function of ovaries with endometriosis.

Regulation of Inflammasomes by Application of Omega-3 Polyunsaturated Fatty Acids in a Spinal Cord Injury Model.

Omega-3 polyunsaturated fatty acids (PUFA n3) ameliorate inflammation in different diseases and potentially improve neurological function after neuronal injury. Following spinal cord injury (SCI), inflammatory events result in caspase-1 mediated activation of interleukin-1 beta (IL-1b) and 18. We aim to evaluate the neuroprotective potency of PUFA n3 in suppressing the formation and activation of inflammasomes following SCI. Male Wistar rats were divided into four groups: control, SCI, SCI+PUFA n3, and SCI+Lipofundin MCT (medium-chain triglyceride; vehicle). PUFA n3 or vehicle was intravenously administered immediately after SCI and every 24 h for the next three days. We analyzed the expression of NLRP3, NLRP1, ASC, caspase-1, IL-1b, and 18 in the spinal cord. The distribution of microglia, oligodendrocytes, and astrocytes was assessed by immunohistochemistry analysis. Behavioral testing showed significantly improved locomotor recovery in PUFA n3-treated animals and the SCI-induced upregulation of inflammasome components was reduced. Histopathological evaluation confirmed the suppression of microgliosis, increased numbers of oligodendrocytes, and the prevention of demyelination by PUFA n3. Our data support the neuroprotective role of PUFA n3 by targeting the NLRP3 inflammasome. These findings provide evidence that PUFA n3 has therapeutic effects which potentially attenuate neuronal damage in SCI and possibly also in other neuronal injuries.

Genetic inhibition of RIPK3 ameliorates functional outcome in controlled cortical impact independent of necroptosis

Traumatic brain injury (TBI) is a leading cause of death and disability with no specific effective therapy, in part because disease driving mechanisms remain to be elucidated. Receptor interacting protein kinases (RIPKs) are serine/threonine kinases that assemble multi-molecular complexes that induce apoptosis, necroptosis, inflammasome and nuclear factor kappa B activation. Prior studies using pharmacological inhibitors implicated necroptosis in the pathogenesis of TBI and stroke, but these studies cannot be used to conclusively demonstrate a role for necroptosis because of the possibility of off target effects. Using a model of cerebral contusion and RIPK3 and mixed lineage kinase like knockout (MLKL−/−) mice, we found evidence for activation of RIPK3 and MLKL and assembly of a RIPK1-RIPK3-MLKL necrosome complex in pericontusional brain tissue. Phosphorylated forms of RIPK3 and MLKL were detected in endothelium, CD11b + immune cells, and neurons, and RIPK3 was upregulated and activated in three-dimensional human endothelial cell cultures subjected to CCI. RIPK3−/− and MLKL−/− mice had reduced blood-brain barrier damage at 24 h (p < 0.05), but no differences in neuronal death (6 h, p = ns in CA1, CA3 and DG), brain edema (24 h, p = ns), or lesion size (4 weeks, p = ns) after CCI. RIPK3−/−, but not MLKL−/− mice, were protected against postinjury motor and cognitive deficits at 1–4 weeks (RIPK3−/− vs WT: p < 0.05 for group in wire grip, Morris water maze hidden platform trials, p < 0.05 for novel object recognition test, p < 0.01 for rotarod test). RIPK3−/− mice had reduced infiltrating leukocytes (p < 0.05 vs WT in CD11b + cells, microglia and macrophages), HMGB1 release and interleukin-1 beta activation at 24–48 h (p < 0.01) after CCI. Our data indicate that RIPK3 contributes to functional outcome after cerebral contusion by mechanisms involving inflammation but independent of necroptosis.

Activation of Interleukin-1 Beta in Arterialized Vein Grafts and the Influence of the -511C/T IL-1β Gene Polymorphism.

The interleukin-1 family is associated with innate immunity and inflammation. The latter has been linked to the genesis of cardiovascular diseases. We, therefore, investigated whether interleukin-1 beta (IL-1β) is activated during arterialization of vein grafts. First, we examined the activation of IL-1β using the rat arterialized jugular vein serially sampled for up to 90 days. IL-1β expression increased 18 times on day 1 in the arterialized rat jugular vein and remained five times above nonarterialized vein levels for up to 90 days. Similarly, IL-1β expression increased early (1–5 days) in human vein graft autopsy samples compared with late phases (1–4 years). Activation was also detected in ex vivo arterialized human saphenous veins. Upon stratification of the results, we uncovered a T allele promoter attenuating effect in IL-1β activation in response to hemodynamic stress. Altogether, the results show that IL-1β is activated during arterialization of vein grafts in rats and humans, and this response is modulated by -511C/T IL-1β gene polymorphism. It is tempting to speculate that the activation of IL-1β, and consequently local inflammation, modulates early vascular remodeling and that the gene polymorphism may be useful in predicting outcomes or assisting in interventions.

Myeloid differentiation factor 88 is up-regulated in epileptic brain and contributes to experimental seizures in rats

Accumulating evidence supports that activation of inflammatory pathways is a crucial factor contributing to the pathogenesis of seizures. In particular, the activation of interleukin-1 beta (IL-1β) system exerts proconvulsant effects in a large variety of seizure models. Myeloid differentiation factor 88 (MyD88) is a critical adaptor protein in the signaling cascade elicited by IL-1β. The present study aimed to investigate the expression pattern of MyD88 in rat models of seizures and in patients with refractory temporal lobe epilepsy (TLE), and to study the role of MyD88 in epileptic seizures. Our results revealed that MyD88 was up-regulated in the hippocampus of rats in the lithium-pilocarpine model of acute seizures. Importantly, MyD88 overexpression was also significantly present in the brain from chronic epileptic rats and the temporal neocortex specimens from drug-resistant TLE patients. In the acute seizure model, both the behavioral and electrographic seizure activities were record and analyzed in rats for 90min, starting immediately after pilocarpine injection. ST2825, a synthetic MyD88 inhibitor, was administered intracerebroventricularly (2.5–5.0–10μg in 2μl) 20min before pilocarpine injection. We found that ST2825 at doses of 5μg and 10μg significantly inhibited the pilocarpine-induced behavioral and electrographic seizures. Moreover, 10μg ST2825 prevented the proconvulsant actions of IL-1β. As previous evidence suggested that IL-1β proconvulsant effects was mediated by enhancing the phosphorylation level of the NR2B subunit of N-methyl-d-aspartate (NMDA) receptor, we then probed whether this molecular was involved in the effect of the pharmacological inhibition. Our results revealed that 10μg ST2825 markedly reversed the increased Tyr1472-phosphorylation of the NR2B subunit of NMDA receptor observed in the proconvulsant conditions of IL-1β and in seizures induced by pilocarpine alone. These findings indicate that altered expression of MyD88 might contribute to the pathogenesis of seizures and targeting of this adaptor protein might represent a novel therapeutic strategy to suppress seizure activities.

The Influence of Cigarette Smoke on the Selected Bronchoalveolar Cells in Experiment

The occurence of lung diseases (obstructive, malignant) resulting from smoking has an increasing tendency. The lung is the primary organ at risk from the effects of inhaled cigarette smoke and smoking has been implicated as a contributing factor to the causation of various respiratory diseases. The aim of presented work was to find out the subchronic effect of the 6-month exposure to cigarette smoke on the selected inflammatory and cytotoxic parameters of bronchoalveolar lavage in W rats and thus to contribute to understanding of the mechanism of action of tobacco smoke and/or path mechanism of lung injury developed after cigarette smoking. In special chamber, the animals smoked 8 standard research 1R1 type of cigarettes per day, except Saturdays and Sundays, during 6 months. The daily concentration of total particulate matter (TPM)/m3 air for two hours per exposure requiring to burn eight cigarettes was 85 mg. Animals were sacrificed after the 6-month exposure and bronchoalveolar lavage (BAL) was performed and selected inflammatory and cytotoxic BAL parameters were examined and compared with the control group. Following BAL parameters were investigated: the total cell and alveolar macrophages (AM) count in BAL, the differential cell count (% of AM, % of polymorphonuclears--PMN, % of lymphocytes--Ly), proportion of immature AM, proportion of bi-nucleated cells--BNC, viability, the phagocytic activity of AM, cytokines TNF-alpha (tumor necrosis factor alpha) and IL-1beta (interleukin-1beta). A) The 6-month smoking of eight cigarettes daily significantly changed prevailing number of examined BAL parameters; B) The presence of inflammatory and cytotoxic responses in lung tissue can probably signalize beginning or developing of disease process.

Irsogladine maleate counters the interleukin‐1β‐induced suppression in gap‐junctional intercellular communication but does not affect the interleukin‐1β‐induced zonula occludens protein‐1 levels in human gingival epithelial cells

Irsogladine maleate counters gap junctional intercellular communication reduction induced by interleukin-8 or Actinobacillus actinomycetemcomitans in cultured human gingival epithelial cells. Interleukin-1 beta is involved in periodontal disease. Little is known, however, about the effect of interleukin-1 beta on intercellular junctional complexes in human gingival epithelial cells. Furthermore, irsogladine maleate may affect the actions of interleukin-1 beta. In this study, we examined how interleukin-1 beta affected gap junctional intercellular communication, connexin 43 and zonula occludens protein-1, and how irsogladine maleate modulated the interleukin-1 beta-induced changes in the intercellular junctional complexes in human gingival epithelial cells. Human gingival epithelial cells were exposed to interleukin-1 beta, with or without irsogladine maleate. Connexin 43 and zonula occludens protein-1 were examined at mRNA and protein levels by real-time polymerase chain reaction and western blotting, respectively. Gap junctional intercellular communication was determined using the dye transfer method. The expression of zonula occludens protein-1 was also confirmed by immunofluorescence. Interleukin-1 beta decreased connexin 43 mRNA levels, but increased zonula occludens protein-1 mRNA levels. Irsogladine maleate countered the interleukin-1 beta-induced reduction in gap junctional intercellular communication and connexin 43 levels. However, irsogladine maleate did not influence the increased zonula occludens protein-1 levels. The effect of interleukin-1 beta on gap junctional intercellular communication and tight junctions of human gingival epithelial cells is different. The recovery of gap junctional intercellular communication by irsogladine maleate in the gingival epithelium may be a normal process in gingival epithelial homeostasis.

Activation of interleukin-1beta (IL-1β) signaling in the spinal cord in the rats with experimental cardiac injury

Background The involvement of central nervous system (CNS) interleukin-1beta (IL-1β) in the pathogenesis of acute cardiac injury is still an unexplored issue. The present study was aimed to investigate whether cardiac injury could induce the activation of IL-1β in the spinal cord. Methods and results Cardiac injury model in rats was established by intra-myocardial injection of formalin through the diaphragm. Western blot showed that IL-1β was upregulated in the upper thoracic spinal cord following cardiac injury. The upregulated IL-1β was distributed in the dorsal and ventral horns in the thoracic spinal cord as determined by immunohistochemistry. In situ hybridization demonstrated that IL-1β mRNA localized in the neurons was elevated in response to cardiac injury. The DNA binding activities of two IL-1β transcription factors, activator protein (AP)-1 and nuclear factor kappa B (NF-κB), were enhanced after cardiac injury. In correlated with the upregulation of the spinal IL-1β, the circulating IL-1β level was also increased following cardiac injury. Conclusions Acute cardiac injury could activate the spinal IL-1β signaling, which, in turn, may contribute to disease progression in the acute phase of cardiac injury in clinical practice.

Interleukin-1ra inhibits Fos expression and hyperalgesia in rats

It is known that interleukin-1beta facilitates pain, but the mechanisms of this are not understood. This study investigated the role of interleukin-1beta in the expression of Fos, a marker of neuronal activation, and hyperalgesia caused by injecting complete Freund's adjuvant into one hind paw of the rat. Interleukin-receptor antagonist (interleukin-1ra, 0.005 mg/rat) was given intrathecally twice, 24 h before complete Freund's adjuvant and immediately before complete Freund's adjuvant injection, to block interleukin-1beta action. Fos expression was measured 2 h after complete Freund's adjuvant injection. Paw withdrawal latency was used to assess hyperalgesia. The findings were that interleukin-1ra inhibited inflammation-induced Fos expression and hyperalgesia, which suggests that endogenous interleukin-1beta facilitates transmission of noxious messages at the spinal level by processes involving an enhanced Fos expression.

Innervation and serotoninergic receptors of the testis interact with local action of interleukin-1beta on steroidogenesis

Testosterone secretion by Leydig cells is affected by interleukin-1β (IL-1β). The aim of the present study was to investigate whether partial denervation of the testis or local administration of a serotonin (5-HT) receptor antagonist could alter the changes in testicular steoidogenesis induced by IL-1β. Intratesticular administration of IL-1β was combined with vasectomy or local injection of ketanserin (5-HT type 2 receptor antagonist) in immature hemicastrated rats and the effect of the interventions on testicular steroidogenesis was studied. One day after treatment with local injection of IL-1β induced a significant rise in testosterone secretion that could be prevented by vasectomy (that also means transection of the inferior spermatic nerve). In a model in which neither IL-1β nor ketanserin interfered with steroidogenesis, administration of the receptor antagonist just prior to IL-1β treatment significantly reduced testosterone secretion. Data indicate interaction between testicular nerves and IL-1β action and interaction between testicular 5-HT2 receptors and local effect of IL-1β on testosterone secretion.

Proinflammatory Cytokine Activities, Matrix Metalloproteinase‐3 Activity, and Sulfated Glycosaminoglycan Content in Synovial Fluid of Dogs with Naturally Acquired Cranial Cruciate Ligament Rupture

To measure and compare activities of interleukin-1beta (IL-1beta), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and matrix metalloproteinase-3 (MMP-3); as well as sulfated glycosaminoglycan (S-GAG) content in synovial fluid from dogs with cranial cruciate ligament rupture (CCLR) and dogs with clinically normal stifles. To determine whether correlations exist between demographic and disease-related variables and these synovial markers. Prospective clinical study. Dogs with CCLR (n=23) and Beagles with normal stifle joints (n=21). Synovial fluid activities of proinflammatory cytokines (IL-1beta, IL-6, and TNF-alpha) were determined by bioassay. MMP-3 activity was measured using fluorogenic substrate. S-GAG contents were determined by dimethylmethylene blue dye-binding assay. Mann-Whitney U-test was used to compare results from CCLR joints with normal controls. Spearman's rank correlation test was used to evaluate associations between demographic and disease-related markers and synovial markers. Mean values for synovial markers were significantly higher in CCLR joints compared with controls. IL-1beta and MMP-3 were positively correlated with lameness duration. Activities of proinflammatory cytokines, MMP-3 activity and S-GAG contents were significantly elevated in synovial fluid from canine stifle joints with naturally acquired CCLR. These results indicate that there is joint inflammation and increased release of GAGs into synovial fluid, suggesting that these inflammatory changes are associated with depletion of proteoglycan from articular cartilage. Medical and surgical treatments designed to decrease joint inflammation and breakdown of proteoglycans may be of value in the management of CCLR in the dog.

Familial autoinflammatory diseases: genetics, pathogenesis and treatment

The systemic autoinflammatory diseases are characterized by seemingly unprovoked inflammation, without major involvement of the adaptive immune system. This review focuses mainly on a subset of these illnesses, the hereditary recurrent fevers, which include familial Mediterranean fever, the tumor necrosis factor receptor-associated periodic syndrome, the hyperimmunoglobulinemia D with periodic fever syndrome, and cryopyrin-associated periodic syndromes. This review elucidates how recent advances have impacted diagnosis, pathogenesis, and treatment. More than 170 mutations have been identified in the four genes underlying the six hereditary recurrent fevers. Genetic testing has broadened the clinical and geographic boundaries of these illnesses, given rise to the concept of the cryopyrin-associated periodic syndromes as a disease spectrum, and permitted diagnosis of compound heterozygotes for mutations in two different hereditary recurrent fever genes. Genetics has also advanced our understanding of amyloidosis, a complication of the hereditary recurrent fevers, and suggested a possible role for common hereditary recurrent fever variants in other inflammatory conditions. Recent advances in molecular pathophysiology include the elucidation of the N-terminal PYRIN domain in protein-protein interactions, the description of the NALP3 (cryopyrin) inflammasome as a macromolecular complex for interleukin-1beta activation, and the identification of signaling defects other than defective receptor shedding in patients with tumor necrosis factor receptor-associated periodic syndrome. These molecular insights form the conceptual basis for targeted biologic therapies. Advances in molecular genetics extend our ability to recognize and treat patients with systemic autoinflammatory diseases and inform our understanding of the regulation of innate immunity in humans.

Intermittent Compressive Strain May Reduce Aggrecanase Expression in Cartilage

We tested the hypothesis that intermittent compressive strain reduces the catabolic actions of interleukin-1 beta on chondrocyte metabolism at the gene expression level. We investigated the effects of intermittent compressive strain on mRNA expression in bovine chondrocytes cultured in agarose gel supplemented with or without interleukin-1 beta. Fifteen percent compressive strain amplitude was applied to agarose-chondrocyte constructs at a frequency of 1 Hz. In the absence of interleukin-1 beta, the strain caused an increase in the mRNA levels of anabolic factors like aggrecan and Type II collagen, compared with the levels of anabolic factors in unstrained constructs. These results suggest that the strain may stimulate matrix production in normal cartilage. Interleukin-1 beta is a powerful catabolic agent; in unstrained agarose-chondrocyte constructs, interleukin-1 beta caused a decrease in the mRNA levels of anabolic factors. However, interleukin-1 beta also caused an increase in the mRNA of catabolic factors like aggrecanase-1, aggrecanase-2, and matrix metalloproteinase-3. In the presence of interleukin-1 beta, the strain reduced the mRNA levels of aggrecanase-1 and aggrecanase-2. These results suggest that intermittent compressive strain may protect cartilage by suppressing the expression of aggrecanase-1 and aggrecanase-2, which are thought to be the major matrix-degrading enzymes responsible for cleaving aggrecan.

The Role of Cytokines in Physiological Sleep Regulation

Several growth factors (GFs) are implicated in sleep regulation. It is posited that these GFs are produced in response to neural activity and affect input-output relationships within the neural circuits where they are produced, thereby inducing a local state shift. These GFs also influence synaptic efficacy. All the GFs currently identified as sleep regulatory substances are also implicated in synaptic plasticity. Among these substances, the most extensively studied for their role in sleep regulation are interleukin-1beta (IL-1) and tumor necrosis factor alpha (TNF). Injection of IL-1 or TNF enhances non-rapid eye movement sleep (NREMS). Inhibition of either IL-1 or TNF inhibits spontaneous sleep and the sleep rebound that occurs after sleep deprivation. Stimulation of the endogenous production of IL-1 and TNF enhances NREMS. Brain levels of IL-1 and TNF correlate with sleep propensity; for example, after sleep deprivation, their levels increase. IL-1 and TNF are part of a complex biochemical cascade regulating sleep. Downstream events include nitric oxide, growth hormone releasing hormone, nerve growth factor, nuclear factor kappa B, and possibly adenosine and prostaglandins. Endogenous substances moderating the effects of IL-1 and TNF include anti-inflammatory cytokines such as IL-4, IL-10, and IL-13. Clinical conditions altering IL-1 or TNF activity are associated with changes in sleep, for example, infectious disease and sleep apnea. As our knowledge of the biochemical regulation of sleep progresses, our understanding of sleep function and of many clinical conditions will improve.

Transcriptional regulation of cyclooxygenase-2 in the human microvascular endothelial cell line, HMEC-1: control by the combinatorial actions of AP2, NF-IL-6 and CRE elements.

Interleukin-1beta (IL-1) is a potent inducer of cyclooxygenase-2 (COX-2) and prostaglandin biosynthesis in many types of cells, yet little is known about the molecular mechanisms regulating IL-1 mediated prostanoid biosynthesis in the endothelium of the microvasculature. Therefore, we examined the cis- and trans-acting factors regulating IL-1-induced COX-2 expression in the human microvascular endothelial cell line, HMEC-1. IL-1 enhanced steady state levels of COX-2 protein and mRNA synthesis by approximately 2-fold which preceded a 2-fold increase in PGF(alpha) biosynthesis. Expression of a series of COX-2 promoter-luciferase constructs in IL-1 treated HMEC-1 cells revealed that the 'full length' (-1432/+59 bp) promoter was 10 times more active than the SV-40 promoter/enhancer and that it could be further activated by IL-1. Surprisingly however, all except for the shortest COX-2 promoter construct retained the ability to respond to IL-1 and luciferase activity driven by -191/+59 bp COX-2 promoter was as responsive to IL-1 as the full-length promoter. Moreover, site-directed promoter mutagenesis and electophoretic mobility shift assays (EMSA) indicate that the combinatorial actions of AP2, NF-IL6, and CRE elements are critical for both constitutive and IL-1-inducible COX-2 promoter activity. Understanding the mechanism(s) regulating COX-2 gene expression and prostaglandin biosynthesis in the microvasculature has important implications with regard to inflammation and angiogenesis in vivo.

IkappaBbeta-related proteins in normal and transformed colonic epithelial cells.

The transcription factor nuclear factor-kappaB (NF-kappaB) regulates genes that can influence cell proliferation, apoptosis, and inflammatory responses. Since these events can contribute to carcinogenesis, we examined the expression of NF-kappaB inhibitory proteins (IkappaBs) in normal and transformed colonic epithelial cells. Immunohistochemical analysis of the mouse colon revealed a high level of IkappaBbeta expression in epithelial cells relative to the rest of the tissue, whereas IkappaBalpha was found primarily in cells of the lamina propria. Mouse colon tumors showed a similar cell-specific staining pattern. Immunoblot analysis of IkappaBbeta from mouse colonocytes and the human HT-29 colon cancer cell line indicated that most of the IkappaBbeta in these cells was similar to the C-terminal-truncated IkappaBbeta2 isoform. Cell fractionation studies were consistent with IkappaBbeta being a major regulator of p65-p50 NF-kappaB complexes in HT-29 cells. Interestingly, two larger proteins specifically recognized by IkappaBbeta antibodies (p106 and p112) were found in HT-29 cells and in colon tissue of carcinogen-exposed mice. The p106 and p112 proteins bound to NF-kappaB, and their levels changed during the transient interleukin-1beta activation of NF-kappaB in HT-29 cells. Evidence was obtained indicating that p106 and p112 are stably ubiquitinated forms of IkappaBbeta. We propose that deficiencies in the proteasomal degradation of IkappaBbeta lead to p106 and p112 accumulation, which in turn alter NF-kappaB regulation in colon cancer cells.

Transforming growth factor-beta1 is a potent inhibitor of interleukin-1beta action in whole ovarian dispersates.

Transforming growth factor beta1 (TGFbeta1) acts as an inhibitor of the actions of interleukin-1beta (IL-1beta) in various organ systems. In order better to understand the inter|P-actions between these polypeptides in the ovary, we evaluated the effect of TGFbeta1 co-treatment on various IL-1beta-mediated actions in cultures of whole ovarian dispersates. Treatment with IL-1beta enhanced media accumulation of nitrites (4.8-fold), prostaglandin E2 (PGE2, 3. 9-fold) and lactate (2.0-fold), and enhanced glucose consumption (2. 1-fold). Treatment with TGFbeta1 alone did not significantly affect any of these parameters. However, the addition of TGFbeta1 inhibited IL-1beta-stimulated nitrite (100%), PGE2 (44%) and lactate (78%) accumulation and inhibited IL-1beta-stimulated glucose consumption (74%) in a dose-dependent manner. The addition of TGFbeta1 also suppressed the steady-state levels of IL-1beta-stimulated IL-1beta, type I IL-1 receptor and IL-1 receptor antagonist transcripts (98, 67 and 83% inhibition respectively). These data suggest that TGFbeta1 is capable of inhibiting several IL-1beta-stimulated endpoints. Since IL-1 has been identified as a possible proinflammatory mediator of ovulation and TGFbeta has been implicated as a promotor of fibrosis and healing, we speculate that IL-1 and TGFbeta might play antagonistic roles in the normal ovulatory sequence.

Inhibition of NMDA receptor-mediated synaptic transmission in the rat dentate gyrus in vitro by IL-1 beta.

The action of interleukin-1 beta (IL-1 beta) and its receptor antagonist IL-1ra were investigated on dual component, isolated AMPA and NMDA field excitatory post-synaptic potentials (EPSP) and on the induction and maintenance of long-term potentiation in the rat dentate gyrus in vitro. Perfusion with IL-1 beta (1 ng/ml) for 1 h had no significant effect on the dual component EPSP or the isolated AMPA-EPSP. In contrast IL-1 beta had a significant inhibitory effect on the isolated NMDA-EPSP amplitude (54 +/- 7% at 1 h compared with controls; n = 9; p < 0.001). This effect was fully antagonized in the presence of 100 ng/ml IL-1 receptor antagonist. IL-1 beta also inhibited LTP of the dual component EPSP but had no effect on the maintenance phase when applied post-induction of LTP. This study demonstrates for the first time that the inhibitory effect of IL-1 beta on LTP in the dentate gyrus may be at least partially due to a block of post-synaptic NMDA receptors.

A novel SP-1 site in the human interleukin-1 beta promoter confers preferential transcriptional activity in keratinocytes.

To investigate the mechanisms of transcriptional activation of interleukin-1beta (IL-1beta) in non-monocytic cells, we constructed a series of reporter plasmids with the bacterial chloramphenicol acetyltransferase gene linked to various parts of the human IL-1beta promoter and performed transient transfection experiments. We identified a promoter segment that activates transcription most efficiently in keratinocytes. Electrophoretic mobility shift assays (EMSA) with a 43-mer oligonucleotide derived from the functionally identified cis-acting element revealed specific complexes. By competition analysis with transcription factor consensus sequence oligonucleotides and by immunosupershift, transcription factor SP-1 or a closely related protein was shown to bind to this regulatory element. The closest match to the known SP-1 consensus sequence within the respective region is a TCCCCTCCCCT motif. Mutation of this motif almost completely, and specifically, abolished the binding of two low-mobility complexes and led to a 95% decrease of constitutive transcriptional activation of a reporter construct IL-1beta (-170/+108). Likewise, activation of this reporter construct by tumor necrosis factor-alpha depended on the SP-1 site. These observations suggest that a so-far-unrecognized SP-1 site in the human IL-1beta promoter may participate in the transcriptional regulation of this gene in keratinocytes.

Human endometrial expression of granulocyte colony-stimulating factor (G-CSF) and its receptor, stimulation of endometrial G-CSF production by interleukin-1 beta, and G-CSF inhibition of choriocarcinoma cell proliferation.

To investigate the expression, regulation thereof, and actions of human endometrial granulocyte colony-stimulating factor (G-CSF). Endometrial expression of messenger ribonucleic acids for G-CSF and its receptor were studied using reverse transcriptase-polymerase chain reaction. In tissue culture, endometrial G-CSF protein production, baseline and in response to interleukin-1 beta, was determined by enzyme-linked immunosorbant assay of the conditioned media. G-CSF effects on proliferation of three choriocarcinoma cell lines were determined. In vivo, human endometrium expressed messenger ribonucleic acids for G-CSF and its receptor throughout the menstrual cycle, and endometrium expressed G-CSF protein in vitro. Interleukin-1 beta stimulated endometrial G-CSF protein production in time and dose dependent manners. G-CSF inhibited proliferation of two choriocarcinoma cell lines. These results suggest that 1) G-CSF may have physiologic roles in the endometrium throughout the menstrual cycle; 2) endometrial G-CSF protein production is stimulated by interleukin-1 beta; and 3) that G-CSF may, in part, mediate local actions of interleukin-1 beta and modulate trophoblast proliferation.