胎膜早破与孕妇阴道微生态 及血清IL-10、IL-22、NF-κB的相关性

摘要：目的 探讨胎膜早破与孕妇阴道微生态及血清IL-10、IL-22、NF-kB的相关性。方法 选取我院妇产科收治的84例胎膜早破孕妇为胎膜早破组,100例正常孕妇为正常孕妇组及100例正常未怀孕妇女为正常妇女组。比较3组对象阴道分泌物各细菌阳性率、阴道微生态状态及各组间血清IL-10、IL-22、NF-kB水平。对胎膜早破孕妇阴道微生态失衡与血清IL-10、IL-22、NF-kB水平进行Pearson相关性分析。结果 胎膜早破组孕妇阴道乳杆菌（79.8%）、大肠埃希菌（48.8%）、溶血葡萄球菌（22.6%）检出率均显著高于正常孕妇组和正常妇女组（均P<0.05）。胎膜早破组患者阴道pH（6.87±0.75）、阴道微生态失衡率（40.5%）均显著高于正常孕妇组和正常妇女组,H2O2阳性率（11.9%）低于正常孕妇组（21.0%）和正常妇女组（23.0%）,差异均有统计学意义（均P<0.05）。胎膜早破组孕妇血清IL-10、IL-22、NF-kB水平[（51.28±6.58）pg/mL、（45.91±7.13）pg/mL、（30.47±3.27）ng/mL]均显著高于正常孕妇组和正常妇女组。经过Pearson相关性分析,IL-10、IL-22、NF-kB水平与胎膜早破孕妇阴道微生态失衡呈正相关（r=0.657、0.692、0.732,P<0.05）。结论 孕妇阴道微生态环境发生改变引起阴道菌群失调及血清免疫因子的变化,可能是引发胎膜早破的作用机制之一。     

Interactions between NFκB and Its Inhibitor iκB: Biophysical Characterization of a NFκB/iκB-α Complex

The N-terminal domain (1–318 amino acids) of mouse NFB (p65) has been purified to homogeneity from the soluble fraction of Escherichia coli cells expressing this protein. Its complex with a full-length iB- (MAD3, 1–317 amino acids) molecule was generated by binding the E. coli-derived iB- to the purified NFB and purifying the complex by sequential chromatography. The stoichiometry of NFB to iB in the complex was determined to be 2 to 1 by light scattering and SDS–polyacrylamide gel electrophoresis. The secondary structure of the NFB (p65) determined by Fourier-transform infrared (FTIR) spectroscopy is in good agreement with that of the p50 in the crystal structure of the p50/DNA complex, indicating that no significant structural change in NFB occurs upon binding of DNA. The FTIR spectrum of the NFB/iB complex indicates that its secondary structure is composed of 17% -helix, 39% -strand, 18% irregular structures, and 26% -turns and loops. By comparing these data to the FTIR data for NFB alone, it is concluded that the iB (MAD3) in the complex contains 35% -helix, 27% -strand, 22% irregular structures, and 16% -turns and loops. Circular dichroism (CD) analysis of a shorter form of iB (pp40) indicates that it contains at least 20% -helix and that the iB subunit accounts for nearly all of the -helix present in the NFB/iB complex, consistent with the FTIR results. The stabilities of NFB, iB, and their complex against heat-induced denaturation were investigated by following changes in CD signal. The results indicate that the thermal stability of iB is enhanced upon the formation of the NFB/iB complex.     

NF-κB signaling participates in both RANKL- and IL-4-induced macrophage fusion: receptor cross-talk leads to alterations in NF-κB pathways

NF-κB activation is essential for receptor activator for NF-κB ligand (RANKL)-induced osteoclast formation. IL-4 is known to inhibit the RANKL-induced osteoclast differentiation while at the same time promoting macrophage fusion to form multinucleated giant cells (MNG). Several groups have proposed that IL-4 inhibition of osteoclastogenesis is mediated by suppressing the RANKL-induced activation of NF-κB. However, we found that IL-4 did not block proximal, canonical NF-κB signaling. Instead, we found that IL-4 inhibited alternative NF-κB signaling and induced p105/50 expression. Interestingly, in nfκb1(-/-) bone marrow-derived macrophages (BMM), the formation of both multinucleated osteoclast and MNG induced by RANKL or IL-4, respectively, was impaired. This suggests that NF-κB signaling also plays an important role in IL-4-induced macrophage fusion. Indeed, we found that the RANKL-induced and IL-4-induced macrophage fusion were both inhibited by the NF-κB inhibitors IκB kinase 2 inhibitor and NF-κB essential modulator inhibitory peptide. Furthermore, overexpression of p50, p65, p52, and RelB individually in nfκb1(-/-) or nfκb1(+/+) BMM enhanced both giant osteoclast and MNG formation. Interestingly, knockdown of nfκb2 in wild-type BMM dramatically enhanced both osteoclast and MNG formation. In addition, both RANKL- and IL-4-induced macrophage fusion were impaired in NF-κB-inducing kinase(-/-) BMM. These results suggest IL-4 influences NF-κB pathways by increasing p105/p50 and suppressing RANKL-induced p52 translocation and that NF-κB pathways participate in both RANKL- and IL-4-induced giant cell formation.     

The IκB kinase complex in NF-κB regulation and beyond

The IκB kinase (IKK) complex is the signal integration hub for NF-κB activation. Composed of two serine-threonine kinases (IKKα and IKKβ) and the regulatory subunit NEMO (also known as IKKγ), the IKK complex integrates signals from all NF-κB activating stimuli to catalyze the phosphorylation of various IκB and NF-κB proteins, as well as of other substrates. Since the discovery of the IKK complex components about 15 years ago, tremendous progress has been made in the understanding of the IKK architecture and its integration into signaling networks. In addition to the control of NF-κB, IKK subunits mediate the crosstalk with other pathways, thereby extending the complexity of their biological function. This review summarizes recent advances in IKK biology and focuses on emerging aspects of IKK structure, regulation and function.     

核因子κB研究进展

核因子κB(nuclear factor κB,NF-κB)是一种广泛存在于各种细胞、具有多种调节作用的转录因子。它在正常情况下在胞浆内与抑制蛋白(IκB)结合而呈非活性状态。当细胞受到各种刺激原如紫外辐射、细胞因子(如TNF-α、IL-1)、活性氧作用时,NF-κB与IκB解离并进入细胞核内,与特定的启动子结合,从而调控各种基因的表达,如细胞因子、炎症因子、黏附分子等。NF-κB在炎症发生时复杂的细胞因子网络中起着中心调节作用。在细胞增殖、分化和凋亡及肿瘤发生中NF-κB也扮演着重要角色。以NF-κB作为药物作用的靶点,通过调节NF-κB的活性,可改善某些疾病的治疗效果。     

血清IL-37、IL-18、NF-κB与非酒精性脂肪性肝病合并幽门螺杆菌感染的相关性

目的探讨血清白介素-23(IL-23)、白介素-18(IL-18)、核因子-κB(NF-κB)与非酒精性脂肪性肝病(NAFLD)合并幽门螺杆菌(H.pylori)感染的相关性。方法选取2013年10月至2019年10月我院收治的83例NAFLD患者作为研究对象,根据是否合并H.pylori感染分为NAFLD+Hp(+)组(n=34)和NAFLD+Hp(-)组(n=49)。选取同期到我院进行体检的100例健康者为对照组。比较3组对象基本资料及血清IL-37、IL-18、NF-κB水平,并进行Pearson相关性分析和Logistic多元回归分析。结果 NAFLD+Hp(+)组和NAFLD+Hp(-)组患者BMI、SBP、DBP、TC、TG、LDL-C、FPG、UA、ALT、AST、ALP、GGT、IL-37、IL-18、NF-κB水平均高于对照组(均P0.05)。NAFLD+Hp(+)组患者TC、TG、LDL-C、FPG、ALT、AST、IL-37、IL-18、NF-κB水平均高于NAFLD+Hp(-)组(均P0.05)。Pearson相关性分析显示,NAFLD患者TG、LDL-C、FPG、IL-37、IL-18、NF-κB水平及H.pylori感染情况与肝功能指标(ALT、AST)均呈正相关,同时TG、LDL-C、FPG、IL-37、IL-18、NF-κB水平与H.pylori感染情况也均呈正相关(均P0.05)。Logistic多元回归分析显示,TG、LDL-C、FPG、ALT、IL-37、IL-18、NF-κB是NAFLD患者合并H.pylori感染的危险因素。结论 IL-37、IL-18、NF-κB与NAFLD患者合并H.pylori感染有关,且H.pylori感染会引起患者脂质、糖代谢紊乱。     

JAK2 is an important signal transducer in IL-33-induced NF-κB activation

IL-33, a member of the IL-1 family of cytokines, has been shown to activate NF-κB and MAP kinase family through the IL-1 receptor-related protein, ST2L. In this study, we found that IL-33 rapidly activated a tyrosine kinase, JAK2. Interestingly, we demonstrated the functional involvement of JAK2 in IL-33-induced IκBα degradation and NF-κB activation, since a JAK2 inhibitor, AG490, effectively inhibited this signaling pathway. Furthermore, IL-33 failed to induce IκBα degradation and NF-κB activation in JAK2-deficient MEFs expressing ST2L, compared with wild-type MEFs expressing ST2L. In addition, the introduction of wild-type JAK2 but not kinase dead JAK2 mutant (K882R) restored the IL-33-induced efficient activation of NF-κB in JAK2-deficient MEFs expressing ST2L, resulting in the induction of IL-6, CCL2/MCP-1 and CXCL1/KC expression. On the other hand, the activation of ERK, JNK and p38 was unaffected by JAK2 inhibition and JAK2 deficiency. Thus, these data demonstrate that JAK2 plays an important role in regulating IL-33-induced NF-κB activation.     

Lipopolysaccharide-Induced NF-κB Activation in Human Endothelial Cells Involves Degradation of IκBα but Not IκBβ

We studied the signal transduction pathways involved in NF-κB activation and the induction of the cytoprotective A20 gene by lipopolysaccharide (LPS) in human umbilical vein endothelial cells (HUVEC). LPS induced human A20 mRNA expression with a maximum level 2 h after stimulation. The proteasome inhibitorN-acetyl-leucinyl-leucinyl-norleucinal-H (ALLN) and the tyrosine kinase inhibitor herbimycin A (HMA) blocked A20 mRNA expression and partially inhibited NF-κB DNA-binding activity induced by LPS treatment. LPS induced IκBα degradation at 30–60 min after treatment, but did not induce IκBβ degradation up to 120 min. In contrast, TNF-α rapidly induced IκBα degradation within 5 min and IκBβ degradation within 15 min. Cycloheximide did not prevent LPS-induced IκBα degradation, indicating that newly synthesized proteins induced by LPS were not involved in LPS-stimulated IκBα degradation. LPS-induced IκBα degradation was inhibited by ALLN, confirming that ALLN inhibits NF-κB activation by preventing IκBα degradation. Of note, HMA also inhibited LPS-induced IκBα degradation. However, tyrosine phosphorylation of IκBα itself was not elicited by LPS stimulation, suggesting that tyrosine phosphorylation of a protein(s) upstream of IκBα is required for subsequent degradation. We conclude that in HUVEC, LPS induces NF-κB-dependent genes through degradation of IκBα, not IκBβ, and propose that this degradation is induced in part by HMA-sensitive kinase(s) upstream of IκBα.     

NF-κB repressing factor downregulates basal expression and mycobacterium tuberculosis induced IP-10 and IL-8 synthesis via interference with NF-κB in monocytes

Background

Our previous study showed NF-κB repressing factor (NKRF) downregulates IP-10 and IL-8 synthesis in the peripheral blood mononuclear cells and alveolar macrophages of TB patients with high bacterial loads. However, the mechanism underlying the repressive effect of NKRF is not fully understood.

Results

The levels of IP-10, IL-8 and NKRF were significantly up-regulated in THP-1 cells treated with heated mycobacterium tuberculosis (H. TB). NKRF inhibited NF-κB-mediated IP-10 and IL-8 synthesis and release induced by H. TB. The repressive effect of NKRF is mediated via interference with NF-κB (p65) binding and RNA polymerase II recruitment to promoter sites of IP-10 and IL-8.

Conclusions

We have elucidated that direct contact with MTb induces IP-10, IL-8 and a concomitant increase in NKRF in THP-1 cells. The up-regulated NKRF serves as an endogenous repressor for IP-10 and IL-8 synthesis to hinder host from robust response to MTb infection.     

Beyond NF-κB activation: nuclear functions of IκB kinase α

IκB kinase (IKK) complex, the master kinase for NF-κB activation, contains two kinase subunits, IKKα and IKKβ. In addition to mediating NF-κB signaling by phosphorylating IκB proteins during inflammatory and immune responses, the activation of the IKK complex also responds to various stimuli to regulate diverse functions independently of NF-κB. Although these two kinases share structural and biochemical similarities, different sub-cellular localization and phosphorylation targets between IKKα and IKKβ account for their distinct physiological and pathological roles. While IKKβ is predominantly cytoplasmic, IKKα has been found to shuttle between the cytoplasm and the nucleus. The nuclear-specific roles of IKKα have brought increasing complexity to its biological function. This review highlights major advances in the studies of the nuclear functions of IKKα and the mechanisms of IKKα nuclear translocation. Understanding the nuclear activity is essential for targeting IKKα for therapeutics.     

Association of PARP-1, NF-κB,NF-κBIA and IL-6, IL-1β and TNF-α with Graves Disease and Graves Ophthalmopathy

Background

Graves Disease (GD) is an autoimmune disorder affected by an interaction of multiple genes such as Nuclear Factor-κB (NF-κB), Nuclear Factor-κB Inhibitor (NF-κBIA), Poly (ADP-ribose) polymerase-1 (PARP-1) and cytokines like Interleukin-1β (IL-1β), Interleukin-6 (IL-6) and Tumor Necrosis Factor-α (TNF-α) and mostly accompanied by an ocular disorder, Graves Ophthalmopathy (GO). We hypothesize that there is a relationship between GD, GO, polymorphisms of inflammatory related genes and their association with cytokines, which may play important roles in autoimmune and inflammatory processes.

Subjects and methods

To confirm our hypothesis, we studied the polymorphisms and cytokine levels of 120 patients with GD and GO using PCR-RFLP and ELISA methods, respectively.

Results

We found that patients with GG genotype and carriers of G allele of PARP-1 G1672A polymorphism are at risk in the group having GD (p = 0.0007) while having GA genotype may be protective against the disease. PARP-1 C410T polymorphism was found to be associated with GO by increasing the risk by 1.7 times (p = 0.004). Another risk factor for development of GO was the polymorphism of del/ins of NFkB1 gene (p = 0.032) that increases the risk by 39%. Levels of cytokines were also elevated in patients with GD, but no association was found between levels of cytokines and the development of GO as there was no change in levels of cytokines.

Conclusions

We suggest that, PARP-1 and NFkB1 gene polymorphisms may be risk factors for developing Graves Disease and Ophthalmopathy.     

鼻息肉中NF-κB的活化对IL-8转录的影响及意义

目的 通过检测鼻息肉组织中核因子кB(NF-кB)的活化及白介素-8(IL-8)的转录水平,探讨鼻息肉组织中NF-кB的活化对IL-8转录的影响及临床意义.方法分别应用凝胶电泳迁移实验法、蛋白免疫印迹法、免疫组织化学法及逆转录聚合酶链反应法检测47例鼻息肉患者(鼻息肉组)的息肉组织中NF-κB的活性及其p65亚基蛋白水平、IL-8的组织定位及转录水平;以22例鼻中隔手术患者中鼻甲黏膜组织作为阴性对照(对照组);对NF-кB的活性及其p65亚基蛋白水平与IL-8的转录水平进行Pearson's相关性分析.结果 EMSA测得鼻息肉组患者息肉组织中NF-κB的活性(216.51±17.33)较对照组(63.57±5.26)显著增高(P<0.01);Western Blot 测得鼻息肉组NF-κB亚基p65 蛋白的水平(153.72±9.15)较对照组(73.92±6.74)显著增高(P<0.05);半定量RT-PCR 测得IL-8 mRNA的转录水平(0.95±0.08)也显著高于对照组(0.23±0.03)(P<0.05);Pearson's相关性分析结果提示:鼻息肉组患者息肉组织中NF-κB的活性及其p65亚基蛋白水平与IL-8的转录水平呈显著正相关性(r值分别为 0.78 & 0.53,均P<0.01).结论 IL-8是鼻息肉组织中NF-кB激活后所分泌的重要的炎性细胞因子,NF-кB和IL-8引起的局部微环境的改变可能是鼻息肉发病的重要因素.