新生儿细菌感染血清免疫球蛋白M和铜蓝蛋白的变化

目的　探讨新生儿细菌感染血清免疫球蛋白M(IgM )和铜蓝蛋白 (CP)的变化对新生儿细菌感染的意义。方法　用散射比浊法检测 17例新生儿细菌感染和 19例正常足月新生儿血清IgM和CP及 10例新生儿细菌感染治疗前后IgM和CP。结果　正常足月新生儿IgM和CP分别为 0 .2 2± 0 .0 6 g/L和 0 .0 9± 0 .0 4 g/L ,新生儿细菌感染组 (n =17)IgM和CP分别为 0 .5 8± 0 .30 g/L和 0 .16± 0 .0 6 g/L ,均较对照组明显升高 ,有显著性差异 (P <0 .0 5 )。感染组治疗前后 (n =10 )IgM分别为 0 .5 2± 0 .2 3g/L和 0 .70± 0 .30 g/L ,有显著性差异(P =0 .0 14 ) ;而感染组治疗前后CP比较无显著性差异。结论　IgM和CP的升高可作为诊断新生儿细菌感染的指标 ,但对预后判断无明显意义     

Serum ferritin and ceruloplasmin as coronary risk factors

Iron and copper catalyze lipid peroxidation in vitro, and recentepidemiological data suggest that these metal ions might alsobe involved in human coronary heart disease. We tested the hypothesisby investigating whether the storage proteins ferritin and ceruloplasminwere coronary risk factors. A nested case-control study was set up in middle-aged dyslipidaemicparticipants of the Helsinki Heart Study: a placebo-controlledcoronary primary prevention trial with gemfibrozil Of the 140subjects with cardiac end-points (non-fatal myocardial infarctionor cardiac death) 136 were matched with controls for geographicalarea and drug treatment (gemfibrozil-placebo). Frozen baseline serum samples were used in the analyses of ferritinand ceruloplasmin. Using logistic regression analyses no incrementin coronary risk was detected with increasing ferritin levels(P=0.8 for trend). Ceruloplasmin was higher 349 ± 86vs 317 ± 77mg. l^–1 (P<0.001) in cases than incontrols and the risk in the highest fertile was two-fold (oddsratio 21; 95% CI 1.3-4.2) compared to the lowest (P<0.005for trend). The risk of high ceruloplasmin was influenced bylipoprotein cholesterol concentrations, with an odds ratio of2.4 (95% CI 1.3-4.4) in subjects with high low density lipoproteincholesterol and of 11.3 (95% CI 2.5-52.2) in subjects with lowhigh density lipoprotein cholesterol. It was concluded that ferritin was not associated with coronaryheart disease in dyslipidaemic, middle-aged men, while therewas a continuous and graded increment in coronary risk withelevating ceruloplasmin level.     

孕妇血清铜蓝蛋白氧化酶活力的变化

目的：探讨孕妇血清铜蓝蛋白氧化酶活力的变化。方法：以Ｏ－Ｄｉａｎｉｓｉｄｉｎ为基质,采用联大茴香胺酶比色法测定８７名孕妇和６５名健康非妊娠妇女血清铜蓝蛋白的活力。结果：妊娠小于８周的妇女与健康非妊娠妇女的ＳＣＰ活力水平差异无显著性,在于８周的妇女ＳＣＰ活力均高于健康非妊娠妇女,而晚期妊娠女ＳＣＰ活力均高于其他各组。结论：妇女妊娠８周后ＳＣＰ升高是其对妊娠期铜、铁代谢改变的一种适应;地一些临床疾病的     

Paramagnetic species in the plasma of dogs with lymphoma prior to and after treatment with doxorubicin. An ESR study

Doxorubicin is a potent cytostatic drug which is applied for the treatment of various kinds of malignant diseases. In spite of the routine use of this drug its major adverse effect, the dose-dependent cardiotoxicity, cannot be prevented yet. However, several clinical trials indicated that iron chelators are able to moderate the noxious effect more efficiently than radical scavenging antioxidants. This in turn supports the idea that doxorubicin-iron complexes are involved in triggering the cardiotoxicity of this drug by catalyzing the formation of oxygen radicals. However, both the mode of generation of doxorubicin-iron complexes and the consequences in vivo are not understood so far. In order to figure out whether or not doxorubicin can utilize iron from the transport protein transferrin for complex formation and prooxidative activities we studied the redox state of iron and its regulatory control by ceruloplasmin and ascorbate in the plasma of dogs suffering from malignant lymphoma by electron spin resonance spectroscopy. The respective electron spin resonance intensities prior to and after treatment with doxorubicin were compared with those from healthy controls. Our results revealed that dogs with lymphoma exhibit lower levels of paramagnetic copper in ceruloplasmin (-22%) and iron in transferrin (-33%) than healthy animals. Likewise the concentration of ascorbate radicals was lower in patients with lymphoma than in healthy subjects. The decreased cupric state of ceruloplasmin is equivalent to a diminished ferroxidase activity in plasma and therefore indicates indirectly an impaired antioxidant activity in these patients. Administration of doxorubicin in vivo further reduced the concentration of paramagnetic copper (-18%) and iron (-13%) while the concentration of ascorbate radicals remained unchanged. This decrease was also seen during the in vitro incubation of plasma with doxorubicin suggesting a direct interaction of the drug with the paramagnetic metal species. Model experiments revealed that the effect is based on a doxorubicin-induced release of iron from transferrin which is enhanced by ascorbate and the subsequent formation of doxorubicin-iron complexes. This mechanism was shown to trigger the formation of hydroxyl radicals from H(2)O(2) and to cause an oxidation of the antioxidant ceruloplasmin. Our data demonstrate that cardiotoxic doxorubicin-iron complexes are not only formed in cardiomyocytes itself as generally assumed, but are also present in the circulation. Therefore, these findings provide an additional rationale for potential benefit of iron chelators during doxorubicin chemotherapy.     

动态监测血清铜蓝蛋白水平对MODS早期诊断及预后的评估意义

目的：探讨血清中铜蓝蛋白动态变化对多器官功能障碍综合征（MODs）患者病因判断和预后评估的价值。方法：于入院当天分别检测60例MODS患者（MODS组）、30例非MODS患者（对照组）血清铜蓝蛋白（CP）、超敏C反应蛋白（CRCP）、α-酸性糖蛋白（AAG）及乳酸的含量,并对MODS组进行组内比较,入选的住院患者均进行急性生理和慢性健康评分（APACHE1I）和MODS评分;于第3、5、7天分别对MODs组患者进行血清CP、CRCP、AAG乳酸的含量进行测定,并行组内比较。结果：MODS组APACHEII、MODS评分、CP、CRCP、AAG与对照组比较,差异具有统计学意义（P〈0．05）;无改善或恶化的MODS组患者,随着时间的推移,比较上述指标在各时间段的变化,差异均具有统计学意义（P〈0．05）。结论：MODS患者CP、CRCP、AAG的检测有助于MODS早期诊断;随着病情的进展,铜蓝蛋白水平有不同程度的增高,有助于对MODS预后判断。     

银屑病患者血清铜蓝蛋白和铜水平

本文测定了70例寻常性银屑病(PV)患者和30例正常人血清铜蓝蛋白(CP)和铜(Cu)水平。结果发现患者血清CP和Cu水平均高于正常人,差异显著。两指标增高程度与疾病活动和严重性有关,而与病程长短无关。     

Distinct phenotype of a Wilson disease mutation reveals a novel trafficking determinant in the copper transporter ATP7B

Wilson disease (WD) is a monogenic autosomal-recessive disorder of copper accumulation that leads to liver failure and/or neurological deficits. WD is caused by mutations in ATP7B, a transporter that loads Cu(I) onto newly synthesized cupro-enzymes in the trans-Golgi network (TGN) and exports excess copper out of cells by trafficking from the TGN to the plasma membrane. To date, most WD mutations have been shown to disrupt ATP7B activity and/or stability. Using a multidisciplinary approach, including clinical analysis of patients, cell-based assays, and computational studies, we characterized a patient mutation, ATP7B^S653Y, which is stable, does not disrupt Cu(I) transport, yet renders the protein unable to exit the TGN. Bulky or charged substitutions at position 653 mimic the phenotype of the patient mutation. Molecular modeling and dynamic simulation suggest that the S653Y mutation induces local distortions within the transmembrane (TM) domain 1 and alter TM1 interaction with TM2. S653Y abolishes the trafficking-stimulating effects of a secondary mutation in the N-terminal apical targeting domain. This result indicates a role for TM1/TM2 in regulating conformations of cytosolic domains involved in ATP7B trafficking. Taken together, our experiments revealed an unexpected role for TM1/TM2 in copper-regulated trafficking of ATP7B and defined a unique class of WD mutants that are transport-competent but trafficking-defective. Understanding the precise consequences of WD-causing mutations will facilitate the development of advanced mutation-specific therapies.Copper is essential for the normal development and function of human cells because it serves as a cofactor for many important metabolic enzymes. However, intracellular levels of copper must be tightly regulated (1, 2) because excess copper is toxic. Inborn mutations in the Cu(I)-ATPases, ATP7A [Online Mendelian Inheritance in Man (OMIM) accession no.*606882] or ATP7B (OMIM *300011) result in either systemic copper deficiency or copper accumulation in several tissues, causing Menkes disease or Wilson disease (WD), respectively. WD (OM#277900) is an autosomal-recessive disorder with a heterogeneous clinical presentation; in the absence of family history, diagnosis of WD requires multiple clinical and laboratory studies (3). The large number of rare mutations in the ATP7B gene [>500, (www.hgmd.cf.ac.uk/ac/gene.php?gene=ATP7B)] contribute to the difficulty in making genotype-phenotype associations. Presently, about two dozen mutations found in WD patients have been characterized in detail (4–7). These studies revealed that the most common effect of a WD mutation is ATP7B misfolding, which results in retention of newly synthesized ATP7B in the endoplasmic reticulum (ER), a marked decrease in protein stability, and loss of Cu(I)-transport activity (8, 9). Destabilization and inactivation of ATP7B explain the common phenotypic manifestations in WD, such as impaired copper export from the liver and the lack of copper incorporation into secreted cuproenzymes, such as ceruloplasmin (CPN).ATP7B and the highly homologous ATP7A (Menkes disease protein) play central roles in maintaining copper levels in cells. These proteins belong to the evolutionarily conserved family of P_1B-ATPases, which use the energy of ATP hydrolysis to transport copper from the cytosol across cellular membranes (Fig. 1A). ATP7A and ATP7B load copper onto newly synthesized cupro-proteins in the late Golgi and remove excess copper from the cytosol after relocating to vesicles, which in turn traffic to the plasma membrane to release copper into the extracellular milieu. In low and basal copper, ATP7A and ATP7B are located predominantly in a subcompartment of the trans-Golgi network (TGN) marked by syntaxin 6 (10). When copper levels increase, ATP7A and ATP7B exit the TGN in distinct vesicles; ATP7B vesicles move to the apical region in polarized epithelia, whereas ATP7A vesicles move to the basolateral region. Because copper-dependent ATP7B trafficking is a complex process, the precise sequence of events and the function of trafficking determinants in ATP7B’s structure are yet to be fully understood.Open in a separate windowFig. 1.Hypothetical ATP7B model and multiple species alignment of the conserved regions, amino acids 621–668, in the two Cu-ATPases. (A) A hypothetical ATP7B ribbon model, generated by UCSF Chimera, showing the conserved core organization (20). The two large cytoplasmic loops in the core structure are: the A domain (actuator, green), between TM4 and TM5, which contains the phosphatase activity; and the N and P domains (nucleotide binding and phosphorylation, red) between TM6 and TM7, which bind ATP (N), catalyzing formation of a phosphorylated intermediate (P) as part of the catalytic cycle. The eight TMs (yellow are): TM1 (amino acids 645–670), TM2 (including the platform helix, amino acids 694–722), TM3 (amino acids 729–749), TM4 (amino acids 765–786), TM5 (amino acids 916–942), TM6 (amino acids 967–1004), TM7 (amino acids 1307–1345), and TM8 (amino acids 1352–1373). The six N-terminal MBDs (blue, N-MBDs, also referred to as the N-terminal domain of ATP7B, N-ATP7B) (61, 62) were manually positioned onto the published model. The box approximates the region of the multiple species alignment shown in B. (B) A multiple species alignment of human ATP7B sequence 621–668 (Upper) and ATP7A sequence 621–668 (Lower). WD patient mutations are underlined and in bold. The ATP7B S653 position is marked with an asterisk (bold). Portions of MBD6 and TMD 1 are bracketed. In ATP7A, the bracketed sequence shows the deleted region that is replaced with two amino acids (IR) in a patient with Occipital Horn Syndrome. The deleted sequence of ATP7A is underlined and in bold (35). Alignments were obtained using ClustalW (63). Amino acids that are identical (*), conserved (:), and semiconserved (.) are shown.We previously developed a comprehensive set of cell-based assays that use both polarized hepatic cells and fibroblasts lacking ATP7B and ATP7A (derived from a Menkes disease patient) to evaluate the activity, stability, and trafficking of ATP7B and its mutants (11, 12). In this study, we combined these assays with additional mutational analysis and computational studies to dissect the molecular phenotype of WD mutations found in a highly conserved region of ATP7B, G⁶²¹-S⁶⁶⁸. We demonstrate that the S653Y mutation has a distinct “transport-competent/trafficking-defective” phenotype. We also show that the transmembrane segment (TM) that harbors S653 has an important and previously unanticipated role in regulating exit of ATP7B from the TGN in response to copper elevation.     

Reduced serum ceruloplasmin levels in hereditary haemochromatosis

As ceruloplasmin (Cp) seems to be involved in iron mobilization, serum Cp levels were measured in 35 patients with hereditary haemochromatosis (HH), 12 with acquired iron overload (AIO) and 36 healthy subjects. Cp was lower in HH patients than in controls (P < 0.001); no difference was found between untreated HH patients and those on a phlebotomy programme (P = 0.07) and between the HH patients carrying the normal and the mutated alleles of the HFE gene (P = 0.8). Cp levels in AIO subjects were significantly higher than in HH patients (P < 0.004) and similar to those of controls (P = 0.2). No differences in albumin, alpha1 acid glycoprotein and copper serum levels were observed in the three groups.     

Iron in fatty liver and in the metabolic syndrome: a promising therapeutic target

The dysmetabolic iron overload syndrome (DIOS) is now a frequent finding in the general population, as is detected in about one third of patients with nonalcoholic fatty liver disease (NAFLD) and the metabolic syndrome. The pathogenesis is related to altered regulation of iron transport associated with steatosis, insulin resistance, and subclinical inflammation, often in the presence of predisposing genetic factors. Evidence is accumulating that excessive body iron plays a causal role in insulin resistance through still undefined mechanisms that probably involve a reduced ability to burn carbohydrates and altered function of adipose tissue. Furthermore, DIOS may facilitate the evolution to type 2 diabetes by altering beta-cell function, the progression of cardiovascular disease by contributing to the recruitment and activation of macrophages within arterial lesions, and the natural history of liver disease by inducing oxidative stress in hepatocytes, activation of hepatic stellate cells, and malignant transformation by promotion of cell growth and DNA damage.Based on these premises, the association among DIOS, metabolic syndrome, and NAFLD is being investigated as a new risk factor to predict the development of overt cardiovascular and hepatic diseases, and possibly hepatocellular carcinoma, but most importantly, represents also a treatable condition. Indeed, iron depletion, most frequently achieved by phlebotomy, has been shown to decrease metabolic alterations and liver enzymes in controlled studies in NAFLD. Additional studies are warranted to evaluate the potential of iron reductive therapy on hard clinical outcomes in patients with DIOS.     

Prognostic Value of Elevated Serum Ceruloplasmin Levels in Patients With Heart Failure

BackgroundCeruloplasmin (Cp) is a copper-binding acute-phase protein that is increased in inflammatory states and deficient in Wilson's disease. Recent studies demonstrate that increased levels of Cp are associated with increased risk of developing heart failure. Our objective was to test the hypothesis that serum Cp provides incremental and independent prediction of survival in stable patients with heart failure.Methods and ResultsWe measured serum Cp levels in 890 patients with stable heart failure undergoing elective cardiac evaluation that included coronary angiography. We examined the role of Cp levels in predicting survival over 5 years of follow-up. Mean Cp level was 26.6 ± 6.9 mg/dL and demonstrated relatively weak correlation with B-type natriuretic peptide (BNP; r = 0.187; P < .001). Increased Cp levels were associated with increased 5-year all-cause mortality (quartile [Q] 4 vs Q1 hazard ratio [HR] 1.9, 95% confidence interval [CI] 1.4–2.8; P < .001). When controlled for coronary disease traditional risk factors, creatinine clearance, dialysis, body mass index, medications, history of myocardial infarction, BNP, left ventricular ejection fraction (LVEF), heart rate, QRS duration, left bundle branch blockage, and implantable cardioverter-defibrillator placement, higher Cp remained an independent predictor of increased mortality (Q4 vs Q1 HR 1.7, 95% CI 1.1–2.6; P < .05). Model quality was improved with addition of Cp to the aforementioned covariables (net reclassification improvement of 9.3%; P < .001).ConclusionsCeruloplasmin is an independent predictor of all-cause mortality in patients with heart failure. Measurement of Cp may help to identify patients at heightened mortality risk.