Interleukin-1beta induces in vivo tolerance to lipopolysaccharide in mice

Endotoxin or lipopolysaccharide (LPS) tolerance may be partially due to the secretion of potent anti-inflammatory cytokines following severe Gram-negative infections, or by low doses of LPS. In this work, we describe the effects of interleukin-1 (IL-1) and tumour necrosis factor alpha (TNF-), two early cytokines secreted after LPS exposure, in the induction of LPS tolerance. Our results demonstrate that mice treated with three daily doses of 100 ng of IL-1 were tolerant to LPS-induced shock. However, TNF- was unable to induce an LPS refractory state. Given the fact that 100 ng of IL-1 increase the plasma levels of glucocorticoids, we evaluated whether a daily injection of dexamethasone (DEX) alone was able to reproduce the LPS-like tolerant state. However, no signs of LPS refractoriness were detected, except when DEX was administered concomitantly with a dose of IL-1 that does not induce corticosterone secretion (12 ng/mouse). This dose was found to induce in vitro up-regulation of the glucocorticoid receptors (GcR) of peritoneal macrophages following 24 h of treatment. In addition, we demonstrate that IL-1 is capable of inducing the down-regulation of Toll-like receptor 4 (TLR4), a crucial molecule in the signal transduction of LPS. Taken together, our results indicate that IL-1 can generate tolerance to LPS in vivo, and suggest that the regulation of mechanisms of the down-regulation of TLR4, as well as those involved in the expression of GcR and/or in the secretion of glucocorticoids, would be crucial for these effects.     

Role of IL-18 in the secretion of Il-1beta, sIL-1RII, and IL-1Ra by human neutrophils

In the present study we investigated the effect of IL-18 on the production of IL-1β, IL-1Ra and sIL-1RII by human neutrophils. Our observations indicate that rhIL-18 induces IL-1β and, to a lesser extend, IL-1Ra and sIL-1RII production by human neutrophils isolated form peripheral blood. However, this effect was less important in comparison with LPS-stimulation. Moreover, the results obtained suggest that IL-18 can induce priming of neutrophils for IL-1β and, to a lesser extend, IL-1Ra and sIL-1RII production by LPS-stimulated cells. The capacity of IL-18 to serve as an effective modulator for IL-1β and its regulatory proteins may have significance in the inflammatory and immune reactions mediated by IL-1β.     

Protective role of interlekin-1 alpha gene polymorphism in Chinese Han population with sporadic Parkinson's disease

Parkinson's disease is the second most common neurodegenerative disorders after Alzheimer's disease in the elderly. Abundant evidence showed that proinflammatory factors were involved in the pathogenesis of sporadic Parkinson's disease (SPD). Interleukin-1 (IL-1) is a cytokine that plays an important role in neurodegenerative disease. Previous association studies between genetic polymorphisms of IL-1 alpha and PD have showed conflicting results and no such study was done in Chinese. We recruited 533 SPD patients and 530 controls in Chinese Han population to investigate the association of IL-1alpha C-899T allele and risk for PD. Real-time PCR was used to detect the polymorphism, and multiple logistic regression, Chi square test and survival analysis were performed to explore the association. The distribution of IL-1alpha alleles was significantly different between the cases and controls, and the T allele was associated with a reduced risk of PD (OR: 0.72, 95%CI: 0.54-0.97, rho = 0.033). However, survival analysis showed that the T allele did not delay the onset age of PD (T allele vs. non-T allele log rank: chi2 = 0.14, p = 0.70). Our data suggest that the T allele carriers have less inclination to have PD in Chinese Han population.     

IL-1beta induces and TGF-beta reduces vitamin D3-induced bone resorption in mouse calvarial bone cells

Bone cells produce multiple growth factors and cytokines that have effects on bone metabolism and can be incorporated into the bone matrix. The present study was designed to extend these observations by examining the interactions between transforming growth factor-β (TGF-β) or interleukin-1β (IL-1β) and bone cells in a rat long bone culture model. IL-1β regulates several activities of the osteoblast cells derived from rat long bone explants in vitro. IL-1β stimulated cellular proliferation and the synthesis of prostaglandin E₂ and plasminogen activator activity in the cultured cells in a dose-dependent manner. TGF-β is present in the bone matrix and potentially can be released during bone resorption. TGF-β reduced basal bone resorption and inhibited vitamin D₃ [1,25(OH)₂D₃]-induced bone resorption in rat long bone cells. These studies support the role of IL-1β in the pathological modulation of bone cell metabolism, with regard to implication in the pathogenesis of osteoporosis by IL-1β, and that TGF-β is positively inhibiting the bone resorption.     

Alpha4beta1 and alpha4beta7 CD4 T cell numbers increase and CLA CD4 T cell numbers decrease in systemic sclerosis

We studied the expression of adhesion molecules affecting recirculation and homing on peripheral blood CD4(+) T cells of patients with systemic sclerosis (SSc), in order to evaluate whether the distribution of tissue targeted subsets could reflect the participation of internal organs or the extent of cutaneous involvement [i.e. limited cutaneous (lc) and diffuse cutaneous (dc)]. Peripheral blood mononuclear cells (PBMC) from 51 patients with SSc and 19 sex- and age-matched controls were investigated by cytofluorimetric analysis for lymphocyte subpopulations carrying the following surface molecules: CD3, CD4, CLA, alpha4beta7 and alpha4beta1. Standard routine biochemistry and clinical examinations were also performed in all patients. We found that both alpha4beta1(+) and alpha4beta7(+) cells within the CD4(+) T cell population were significantly increased, while CLA(+) CD4(+) T cells were significantly reduced in SSc, compared to healthy donors. Significantly lower absolute numbers of alpha4beta7(+) cells were found in lc- compared to dc-SSc. Patients with oesophageal involvement had high numbers of alpha4beta7(+) cells, while those with nephritis also showed low levels of CLA(+) cells. Lung involvement was related directly to alpha4beta1(+) cell numbers and inversely to alpha4beta7(+) CD4 cell numbers. Taken together, our findings demonstrate that distinct CD4(+) T cell populations with selective homing properties show changes from normal distribution in SSc, and such changes are related to clinical expression and organ involvement in the course of the disease.     

PPP1R3基因多态性与中国汉族人群2型糖尿病的相关性研究

目的　旨在研究 1型蛋白磷酸酶骨骼肌特异的糖原靶向调节亚单位基因 (PPP1R3)Asp90 5Tyr以及 3′ -UTR5bpD/I多态性与安徽省汉人群的 2型糖尿病 (T2DM )相关性。方法　运用PCR -RFLP法对安徽省合肥地区 36 6例汉族受试者 (T2DM患者 2 6 2例 ,健康成人 10 4例 )进行基因型测定。结果　 (1)PPP1R3基因Asp90 5Tyr以及 3′ -UTR 5bpD/I多态性的基因型及等位基因频率在T2DM与健康对照组间分布均没有显著性差异 (P >0 .0 5 )。 (2 )PPP1R3基因Asp90 5Tyr以及3′ -UTR 5bpD/I多态性间呈连锁不平衡 ,其分布频率在不同人群中不尽相同。结论　PPP1R3基因Asp90 5Tyr以及 3′ -UTR 5bpD/I多态性可能在安徽省合肥地区 2型糖尿病发病中不起重要作用。两种多态性的分布表现明显的种族性。     

Interleukin-1 beta enhances and interferon-gamma suppresses activin A actions by reciprocally regulating activin A and follistatin secretion from bone marrow stromal fibroblasts.

Activin A is a multi-functional cytokine with a potent stimulation on erythroid cell differentiation in the bone marrow. The actions of activin A are determined by a balance of the levels of activin A and its inhibitor, follistatin (FS). However, the regulation of its actions in the bone marrow has been unclear. Here we show that bone marrow-derived stromal fibroblasts are the major source of activin A and FS in the bone marrow, and that the production of activin A is enhanced by interleukin-1beta (IL-1beta) and lipopolysaccharide (LPS), whereas interferon-gamma (IFN-gamma) inhibits the secretion of activin A by stromal fibroblasts. Concomitantly, IL-1beta as well as LPS inhibits and IFN-gamma stimulates FS secretion from stromal fibroblasts. Thus, these cytokines potently regulate activin A actions by reciprocal modulation of activin A and FS secretion from stromal fibroblasts. Because activin A exhibits anti-inflammatory effects in various tissues, up-regulation of activin A actions by IL-1beta and endotoxin in the bone marrow may play a protective role against inflammatory processes as well as anaemia. The present results also suggest that the inhibitory effect of IFN-gamma on erythropoiesis is mediated at least in part by a suppression of activin A actions in bone marrow.     

白细胞介素1B-511多态性与侵袭性牙周炎的关系

目的研究中国人群中IL-1B-511位点单核苷酸多态性(single nucleotide polymorphism,SNP)与侵袭性牙周炎(aggressive periodontitis,AgP)之间的关系.方法提取122名AgP患者和95名健康对照者外周静脉血基因组DNA,应用聚合酶链反应-限制性片段长度多态性的方法,分析IL-1B-511位点SNP与AgP的关联性.结果男性AgP组杂合基因型的频率较男性健康对照组升高并有统计学意义(P=0.048);A2 基因型/等位基因A2与吸烟联合作用显著增加了AgP的易感性(基因型:P=0.022;等位基因:P=0.006).结论IL-1B-511位点的SNP可能与中国人群中男性个体的AgP易感性有关;该位点的SNP与吸烟可能对AgP的易感性具有联合效应.     

Interleukin-1β converting enzyme in murine Langerhans cells and epidermal-derived dendritic cell lines

Interleukin (IL)-1β plays an essential role in the induction of T cell-mediated immune responses in skin. Langerhans cells (LC), which constitutively express IL-1β mRNA, have been assumed to be the primary source of IL-1β in murine epidermis. The purpose of this study was to determine whether LC express mRNA for the IL-1β converting enzyme (ICE), a protease that is required for processing pro-IL-1β into an active form. Here, we report that both IL-1β and ICE mRNA are expressed by the Ia⁺ population (i.e. LC) in murine epidermis. Moreover, murine epidermal-derived DC lines (XS series) also express both IL-1β and ICE mRNA, and they secrete relatively large amounts of IL-1β following lipopolysaccharide (LPS) stimulation. Finally, LPS-triggered IL-1β secretion by XS cells is blocked almost completely by the ICE inhibitor acetyl-Tyr-Val-Ala-Asp-CH₂OC(O)-[2,6-(CF₃)₂]Ph. These results demonstrate that LC are the primary source of IL-1β within the epidermis, and suggest that the proinflammatory role of IL-1β may be regulated pharmacologically by ICE inhibitors in vivo.     

Allelic polymorphism in IL-1 beta and IL-1 receptor antagonist (IL-1Ra) genes in inflammatory bowel disease.

Recent reports have shown that allele 2 of the IL-1 receptor antagonist (IL-1Ra) gene is over-represented in ulcerative colitis (UC). Healthy individuals carrying allele 2 of this gene have increased production of IL-1Ra protein. Since the final outcome of the biological effects of IL-1 beta may depend on the relative proportion of these two cytokines, we have studied if a TaqI polymorphism in the IL-1 beta gene, which is relevant to IL-1 beta protein production, may be involved in the genetic susceptibility to UC and Crohn's disease (CD), in association with the established IL-1Ra gene polymorphism. Polymorphisms in the closely linked genes for IL-1 beta and IL-1Ra were typed in 100 unrelated Dutch patients with UC, 79 with CD, and 71 healthy controls. The polymorphic regions in exon 5 of the IL-1 beta gene and in intron 2 of the IL-1Ra gene, were studied by polymerase chain reaction (PCR)-based methods. The IL-1 beta allele frequencies in UC and CD patients did not differ from those in healthy controls. In order to study if the IL-1 beta gene polymorphism might participate synergistically with the IL-1Ra gene polymorphism in susceptibility to UC and CD, individuals were distributed into carriers and non-carriers of allele 2 of the genes encoding IL-1 beta and IL-1Ra, in each of the patient groups and controls. Results indicated a significant association of this pair of genes, estimated by the odds ratio (OR) after performing Fisher's exact test, in the UC group (P = 0.023, OR = 2.81), as well as in the CD group (P = 0.01, OR = 3.79). Thus, non-carriers of IL-1 beta allele 2 were more often present in the subgroup of patients carrying the IL-1Ra allele 2. By contrast, no association of these alleles was detected in the group of healthy controls (P = 1.00, OR = 0.92). These results suggest that the IL-1 beta/IL-1Ra allelic cluster may participate in defining the biological basis of predisposition to chronic inflammatory bowel diseases.     

beta2-adrenergic receptor gene polymorphisms in myasthenia gravis (MG)

The beta2-adrenergic receptor (beta2-AR) belongs to the group of G-protein coupled receptors and is present mainly on skeletal and cardiac muscle cells and lymphocytes. The gene encoding beta2-AR (ADRB2) displays a moderate degree of heterogeneity in the human population. The distribution of polymorphisms at amino acid positions 16, 27 and 164 is changed in asthma, hypertension and obesity. We have earlier reported a decreased density of the beta2-AR on peripheral blood mononuclear cells and the presence of beta2-AR antibodies in patients with MG. Since certain polymorphisms affect the function of the beta2-AR, it was of interest to analyse these in MG. Using allele-specific polymerase chain reaction amplification, we revealed an over-representation of homozygosity for Arg16 and a lower prevalence of homozygosity for Gly16 in MG patients compared with healthy individuals. The increased frequency of homozygosity for Arg16 was due to a contribution from patients with generalized MG but not from patients with only ocular disease. Homozygosity for Glu27 was negatively associated with both the presence of beta2-AR antibodies and severity of disease. Moreover, acetylcholine receptor (AChR) antibodies were more often present in patients being homozygous for Gln27. Our results imply that homozygosity for Arg16 confers susceptibility to generalized MG, and that certain polymorphisms at amino acid position 27 are associated with subgroups of patients.     

Interleukin-1 beta-511 polymorphism and risk of cervical cancer

Cervical cancer is almost invariably associated with infection by human papillomavirus. It is believed that the host genetic factors such as inflammation-induced cytokines may play a role in cervical carcinogenesis. The IL1B gene, encoding IL-1beta cytokine, contains several single nucleotide polymorphisms. One of them which is in the positions -511 (C-T) related with promoter region has been associated with increased IL-1beta production and with increased risk of developing a number of inflammatory diseases and gastric carcinoma. We assessed the association between the IL1B -511 polymorphism and cervical cancer risk in a hospital-based case-control study among 546 Korean women (182 cases; 364 age-matched controls). The allele frequencies of the case subjects (C, 0.42; T, 0.58) were not significantly different from those of control subjects (C, 0.43; T, 0.57). Control subjects were in Hardy-Weinberg equilibrium. The carriers with -511 C/T or T/T genotypes were at higher risk of cervical cancer with odds ratio of 2.42 (95% CI 1.31-4.46, p<0.005). However, there was no difference of cervical cancer risk between C/T heterologous genotypes and T/T homologous genotypes. In conclusion, in Korean population, IL1B -511 C/C genotypes were significantly associated with a decreased risk of cervical cancer.     

Expression of interleukin-1beta mRNA in murine uterine and gestational tissues: relationship with gestational age.

PROBLEM: The pro-inflammatory cytokine interleukin (IL)-1beta has been shown to stimulate the production of prostaglandins (PG) in gestational tissues. Increased PG synthesis is considered a key step in the initiation of labor both at term and preterm. In this study. IL-1beta mRNA in the uterus and gestational tissues of mice during mid to late pregnancy was studied to characterize its tissue specific as well as gestational age expression. METHOD OF STUDY: Gestational tissues (placenta. decidual cap and fetal membranes). uterus, and cervix were collected from pregnant mice during gestation. Total RNA was isolated and probed for the expression of IL-1beta mRNA. RESULTS: There was a significantly increased expression of IL-1beta mRNA in the uterus on day 18 of pregnancy. In the decidual caps, there was increased expression of IL-1beta mRNA on day 14 of pregnancy and a decrease in expression with the onset of labor. In the fetal membranes and placenta, IL-1beta mRNA expression significantly increased on days 14 and 18 of pregnancy. respectively, and then remained elevated for the duration of pregnancy. In the cervix, there was a decrease in expression with labor onset. CONCLUSIONS: The increases in IL-1beta mRNA in the fetal membranes and placenta late in pregnancy are consistent with a localized, tissue specific inflammatory activation involved in the initiation of parturition.     

Interleukin-1 beta impairs brain derived neurotrophic factor-induced signal transduction

The expression of IL-1 is elevated in the CNS in diverse neurodegenerative disorders, including Alzheimer's disease. The hypothesis was tested that IL-1β renders neurons vulnerable to degeneration by interfering with BDNF-induced neuroprotection. In trophic support-deprived neurons, IL-1β compromised the PI3-K/Akt pathway-mediated protection by BDNF and suppressed Akt activation. The effect was specific as in addition to Akt, the activation of MAPK/ERK, but not PLCγ, was decreased. Activation of CREB, a target of these signaling pathways, was severely depressed by IL-1β. As the cytokine did not influence TrkB receptor and PLCγ activation, IL-1β might have interfered with BDNF signaling at the docking step conveying activation to the PI3-K/Akt and Ras/MAPK pathways. Indeed, IL-1β suppressed the activation of the respective scaffolding proteins IRS-1 and Shc; this effect might involve ceramide generation. IL-1-induced interference with BDNF neuroprotection and signal transduction was corrected, in part, by ceramide production inhibitors and mimicked by the cell-permeable C2-ceramide. These results suggest that IL-1β places neurons at risk by interfering with BDNF signaling involving a ceramide-associated mechanism.     

IL-1 alpha gene expression and protein production by fibroblasts from patients with systemic sclerosis.

We examined IL-1 alpha and IL-1 beta gene expression and protein production in human dermal fibroblasts from patients with systemic sclerosis (SSc) to investigate the abnormal function of SSc fibroblasts. Human dermal fibroblasts were biopsied from 13 patients with SSc, three patients with rheumatoid arthritis (RA) and five healthy normal controls (NC). Cells were cultured in serum-free media and total RNA was collected from second or third passage fibroblasts. In cultured SSc fibroblasts, IL-1 alpha and IL-1 beta mRNAs were constitutively expressed and intracellular pro-IL-1 alpha was present. These observations suggest that an autocrine effect of IL-1 alpha contributes to the fibrosis in SSc.     

Gonadotropin treatment restores in vitro interleukin-1beta and tumour necrosis factor-alpha production by stimulated peripheral blood mononuclear cells from patients with idiopathic hypogonadotropic hypogonadism

In the present study, we aimed to investigate the effects of testosterone deficiency and gonadotropin therapy on the in vitro production of tumour necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) by peripheral blood mononuclear cells (PBMCs) from patients with idiopathic hypogonadotropic hypogonadism (IHH) in order to elucidate the modulatory role of androgen in cytokine production. Fifteen male patients with untreated IHH and 15 age-matched healthy male subjects were enrolled in the study. Serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), free testosterone (FT), sex hormone binding globulin (SHBG), prolactin, and IL-2 and IL-4 levels were also measured. In unstimulated cultures, IL-1beta and TNF-alpha secretion were not significantly different between patient and control groups. However, after stimulation with lipopolysaccharide (LPS), secretion of IL-1beta and TNF-alpha was significantly higher in cultures from untreated patients with IHH than in control subjects. Mean FSH, LH and FT levels were significantly lower, whereas SHBG, IL-2 and IL-4 levels were significantly higher in patients with IHH compared than in controls. In patients with IHH, FT negatively affected the serum levels of IL-4 and in vitro secretion of IL-1beta and TNF-alpha. In addition, IL-2 and IL-4 affected the in vitro secretion of IL-1beta in a positive manner. Gonadotropin therapy decreased both TNF-alpha and IL-1beta in PBMCs from patients with IHH. The levels of serum IL-2 and IL-4 were also decreased by therapy. In conclusion, in the present study, gonadotropin treatment restored the in vitro production of IL-1beta and TNF-alpha by PBMCs from patients with IHH, suggesting that androgen modulates proinflammatory cytokine production, at least directly through its effects on PBMCs. It seems probable that this effect plays an important role in the immunosuppressive action of androgens.     

白细胞介素1α基因单核苷酸多态性与甲型H1N1流感易感性的关系

目的 探讨白细胞介素1d(IL-1α)基因单核苷酸多态性(SNP)与甲型H1N1流感易感性的关系.方法 从IL-1α基因启动子区域中选取4个SNP位点rs1800587、rs2856836、rs2856838、rs3783525,针对以上位点建立基于飞行时间质谱分析技术(TOF-MS)鉴定SNP的方法,对167例H1N1流感患者(H1N1组)和192例健康对照人群(对照组)进行检测.确定各SNP位点的等位基因和基因分型;对比两组等位基因和各基因型的频率.结果 rs1800587、rs2856836、rs2856838位点具有T和C两种等位基因,包括TT、TC、CC 3种基因型.rs3783525具有A和T两种等位基因,包括AA、AT和TT3种基因型.H1N1组和对照组rs 1800587位点的等位基因频率差异有统计学意义(x2=12.69,P=0.000,OR=2.424,95％CI=1.472 ～ 3.993),rs2856836,rs2856838,rs3783525等位基因频率在H1N1组和对照组中差异则无统计学意义.H1N1组rs1800587位点CC纯合子频率低于对照组[72.5％(121/167)比87.0％(167/192),P＜0.05],杂合子(TC)频率高于对照组[25.1％(42/167)比12.5％(24/192),P＜0.05],而两组TT纯合子频率差异则不具有统计学意义.H1N1组rs2856836位点杂合子(TC)频率高于对照组[25.7％(43/167)比17.2％(33/192),P＜0.05],TT基因型与CC基因型频率在两组间差异均没有统计学意义.rs2856838位点对照组TT纯合子频率低于H1N1组[4.2％(8/192)比10.8％(18/167),P＜0.05],其余2种基因型TC与CC在两组间差异没有统计学意义.H1N1组rs3783525位点TTT纯合子频率高于对照组[21.0％ (35/167)比13.0％(25/192),P＜0.05],两组间的另两种基因型TC与CC差异也没有统计学意义.结论 IL-1α基因多态性位点rs1800587、rs2856836、rs2856838、rs3783525与甲型H1N1流感易感性相关.