瞬时性受体电位通道香草酸受体5、6与骨代谢的关系

目的:探讨瞬时性受体电位通道香草酸受体5、6与骨代谢的关系。资料来源:应用计算机检索PubMed数据库1999-01/2006-07相关瞬时性受体电位通道方面的文献,检索词“TRPV”,限定文献语言种类为English。资料选择:对资料进行初审,选取包括瞬时性受体电位通道香草酸受体5、6的文献,开始查找全文。纳入标准:对两者及瞬时性受体电位通道家族进行研究的文章。排除标准:研究内容局限于瞬时性受体电位通道香草酸受体1～4的文章。资料提炼:共检索到106篇关于瞬时性受体电位通道香草酸受体的文献,最终纳入30篇符合标准的文献。资料综合:瞬时性受体电位通道香草酸受体5、6是瞬时性受体电位通道超家族中的成员,是专门的上皮样钙离子通道。目前研究已经证明它们在肠道和肾脏等组织中有表达,并对跨细胞钙离子转运起着关键性调控作用。但在骨组织中表达情况相关报道较少,在骨代谢机制上的研究更少,本文针对目前两者与骨代谢的关系进行综述。结论:深入研究瞬时性受体电位通道香草酸受体5、6钙离子通道在骨代谢中的作用,对于那些与骨代谢相关疾病的治疗将能从分子水平上找到解决的方法。     

Effect of Cytokine Genes in the Pathogenesis and on the Clinical Parameters for the Treatment of Multiple Myeloma

In this study, we aimed to explore the association among gene variants of five cytokines, tumor necrosis factor alpha (TNF-α), transforming growth factor beta-1 (TGF-β1), interferon gamma (IFN-γ), interleukin-6 (IL-6), and interleukin-10 (IL-10), and clinical parameters and prognosis in patients with multiple myeloma (MM) treated with novel therapeutic drugs in Turkish population for the first time except TNF-α. We analyzed five cytokine genes in 113 cases with MM and 113 healthy controls. Cytokine genotyping was performed by the polymerase chain reaction–sequence-specific primer method (PCR-SSP). AG genotype associated with high expression in TNF-α gene (–308) variant was found to be significantly higher (p = 0.019), and GG genotype associated with low expression in TNF-α gene (–308) variant was significantly lower in MM group as compared with controls (p = 0.012). IFN-γ (+874) variant TT genotype was increased (p = 0.037), and AA genotype was decreased (p = 0.002) in MM group in contrast to controls. IFN-γ (+874) T allele was higher in MM patients compared with controls (OR = 1.985, p = 0.000), while A allele was significantly lower (OR = 0.5037, p = 0.0005). Multivariate analysis revealed that factors associated with 5-year overall survival (OS) were only IPI III (RR = 1.630, p = 0.018) and thrombocytopenia (RR = 2.207, Cox p = 0.021), while 5-year event-free survival (EFS) was associated with IPI III (RR = 1.524, p = 0.022), thrombocytopenia (RR = 2.902, p = 0.002), APSCT treatment (RR = 1.729, p = 0.035), and female gender (RR = 0.435, p = 0.002) with negative prognostic values. Our results suggested that TNF-α gene (–308) AG genotype and IFN-γ (+874) TT genotype and T allele may have a role on MM, while other cytokines were not associated with the risk of MM.     

Neutralization of heparin activity by neutrophil lactoferrin

Lactoferrin is a prominent component of neutrophil secondary granules, and its blood concentration is increased in certain inflammatory diseases. In contrast to the well-described biochemical characterization of lactoferrin as an iron-binding protein, its physiologic role in the regulation of inflammation and other host defense mechanisms is unclear. In this report, we provide evidence that lactoferrin has a potent heparin-neutralizing activity during thrombin inhibition by the serine proteinase inhibitors (serpins) antithrombin and heparin co-factor II. Activated neutrophil supernatant, which contains lactoferrin and other heparin-binding proteins, could neutralize the heparin-dependent antithrombin-thrombin inhibition reaction. The addition of lactoferrin to plasma corrected the heparin- induced prolongation of blood plasma coagulation as measured by the activated partial thromboplastin time (aPTT). Treatment of whole blood with specific inflammatory mediators, fMLP, lipopolysaccharide (LPS), and tumor necrosis factor-alpha (TNF-alpha) increased the concentration of both plasma lactoferrin and platelet factor 4 while inhibiting the blood anticoagulant activity of heparin as measured by the aPTT. These results suggest that the prothrombotic sequelae of some inflammatory processes may be partly due to various agonists that release neutrophil lactoferrin, which can then neutralize glycosaminoglycan-dependent serpin-thrombin inhibition reactions.     

Methotrexate reduces inflammatory cell numbers, expression of monokines and of adhesion molecules in synovial tissue of patients with rheumatoid arthritis

Methotrexate (MTX) is one of the most widely prescribed drugs in the treatment of rheumatoid arthritis (RA). The mechanism by which MTX exerts its anti-rheumatic effect has not yet been defined. The aim of the present study was to investigate the effect of MTX treatment (7.5- 15 mg/week) on synovial tissue in RA. For this purpose, synovial biopsies were taken from 11 RA patients before and 16 weeks after initiation of MTX therapy. Immunohistochemistry was performed using monoclonal antibodies (MAb) specific for CD3, CD4, CD8, CD22, CD25, CD38, CD68, MAb67, Ki67, interferon gamma (IFN-gamma), interleukin (IL)- 1alpha, IL-1beta, tumour necrosis factor alpha (TNF-alpha), E-selectin, ICAM-1 and VCAM-1. All parameters for disease activity improved during the period of treatment. Immunohistochemical analysis revealed a statistically significant decrease in scores for CD3, CD8, CD38, CD68, Ki67, IL-1beta, TNF-alpha and the adhesion molecules E-selectin and VCAM-1. The observed decrease in synovial scores for inflammatory cells, monokines and adhesion molecules suggests that the anti- inflammatory effect of MTX is, in part, dependent on a reduction in monokine-inducible vascular adhesion molecules and subsequent reduction of cell traffic into joints.      

Heparin cofactor II-proteinase reaction products exhibit neutrophil chemoattractant activity

The physiologic function of the plasma glycoprotein heparin cofactor II (HCII) is not well understood. An in vivo role for thrombin (IIa) inhibition by HCII in the presence of certain glycosaminoglycans (dermatan sulfate and heparin) can be proposed. Many proteins, such as complement components, can be proteolyzed to generate secondary bioactive molecules. HCII is a substrate for the human neutrophil (PMN) proteinases cathepsin G (CG) and elastase (LE). We found that degradation of HCII by CG or LE generated products with potent PMN chemotactic activity, which did not stimulate the PMN oxidative burst. Our results suggest that HCII may be a physiologic regulator of the acute inflammatory response.