铁稳态与骨质疏松

铁在机体正常的生理活动中扮演着重要角色，铁稳态调节机制已成为目前铁代谢领域研究的热点。近年研究表明，铁稳态失调（铁过载或铁缺乏）与骨代谢异常密切相关，可导致骨质疏松的发生。因此，将近年“铁介导的骨代谢异常”相关文献进行梳理综述，以期为铁代谢与骨代谢的研究提供一定的参考。     

铁代谢与骨质疏松症的相关因素研究现状

铁作为人体生命活动中重要的微量元素之一,其正常的代谢活动在人体内至关重要。铁代谢异常会增加许多骨骼疾病的发病率,尤其是骨质疏松症。铁代谢紊乱不仅促进破骨细胞分化和成骨细胞凋亡,还会抑制成骨细胞的增殖和分化,最终破坏骨重塑的平衡。铁代谢紊乱可使骨的强度和密度降低,增加骨质疏松症的发病率。本文综述了铁超载和铁缺乏对骨质疏松症的影响以及铁代谢紊乱对骨质疏松症的作用机制的研究进展。阐明铁代谢与骨质疏松症的关系,可为临床治疗和新药开发提供思路。     

铁过载与骨质疏松关系的研究进展

铁作为机体必需的营养元素,起着重要的生物学功能,但是铁过多也会对细胞和组织产生危害.已经发现铁过载与骨质疏松之间存在某些联系.铁过载可能引起骨质疏松,但是此病理过程及铁的具体作用尚未明确.最近的报道认为:在实验水平上,铁过载可能抑制成骨细胞的功能并增加破骨细胞的活性;在临床水平上,骨质疏松症发生于多种与铁过载相关的疾病患者中.因此本文就体内铁过载和骨质疏松的关系的临床和实验研究作一综述.     

脑内铁过载与神经退行性疾病的研究进展

背景 铁是人体内极其重要的微量元素,参与了许多生物大分子的构成和基本的生命活动.人体内有一套精密完善的储存、转运、调控系统来维持铁稳态,当这一复杂的网络系统出现障碍时将会导致铁代谢紊乱. 目的 综述脑内铁过载在神经退行性疾病发生发展中的重要作用. 内容 通过对近年来相关文献的总结,主要对铁的转运相关蛋白、铁稳态的调节系统、转运机制等方面对铁过载的形成及其与神经退行性疾病的关系进行了初步探讨,脑内异常高浓度的铁参与了阿尔茨海默病、帕金森病等多种神经退行性疾病的病理过程. 趋向 脑内铁过载引起神经退行性变的机制正被逐步阐明,但仍有许多问题有待解决.通过利用铁螫合剂来降低脑内铁过载可能是治疗这类疾病的一个潜在靶点.     

铁螯合剂在铁过载骨质疏松症中应用前景

骨质疏松症研究是骨科领域一项重要研究课题,骨代谢研究是重中之重.近年大量基础和临床试验研究显示,过多的铁离子可能通过抑制成骨细胞增值、分化促进破骨细胞分化及其功能,引起骨质疏松症.临床祛铁药物铁螯合剂可与铁离子形成大分子复合物而促进铁离子排泄,降低体内铁离子水平及其在各器官组织中的病理性沉积,因而可能具有防治铁过载骨质...     

铁缺乏症婴幼儿母亲铁营养知识调查分析

目的:了解铁缺乏症婴幼儿母亲铁营养知识的现状,为其健康教育提供依据.方法:对215例铁缺乏症婴幼儿的母亲进行铁营养知识问卷调查.结果:铁缺乏症婴幼儿母亲铁营养知识普遍欠缺,第一胎婴幼儿母亲铁营养知识掌握程度低于第二胎及第二胎以上婴幼儿母亲(P＜0.01)；而高学历组母亲其铁营养知识掌握程度明显高于低学历组(P＜0.01).结论:应加强对婴幼儿母索铁营养知识的健康教育,教育的重点对象是第一胎婴幼儿的及低学历的母亲.     

透析患者铁剂应用进展

透析患者普遍存在贫血,在应用促红细胞生成素进行治疗的过程中,常常需要补充铁剂以达到最优的治疗效果.静脉补充铁剂相对于口服铁剂而言更有效,且不良事件发生率低,有逐渐替代口服补铁的趋势,但是铁与有氧呼吸代谢、脂质过氧化、氧化应激等存在密切联系,故在铁剂的应用过程中,有许多未解决的问题.本文概述了透析患者静脉应用铁剂的安全性、有效性及使用铁剂可能的副作用.     

Hepcidin研究进展

Hepcidin是一种主要南肝脏合成的富含半胱氨酸的小分子多肽.hepcidin的表达水平与机体铁负荷、缺氧、贫血、感染及炎症等应激有关.炎症和铁超负荷能上调hepcidin表达,而缺氧及贫血则抑制其表达.hepcidin通过调节肠道铁吸收、巨噬细胞铁释放以及肝脏储存铁的释放,维持机体铁稳态.新近研究发现,hepcidin表达水平或功能的异常与血色素沉着症、炎症性贫血及脓毒症的发生发展有关.     

肝脏铁浓度（LIC )在铁过载后骨代谢异常 研究中的作用

：近年来研究结果提示：铁代谢与骨代谢有着密切的联系,铁过载可致骨代谢异常的发生;同时 还有研究显示肝脏铁浓度（LIC)与体内铁水平呈正相关性,LIC可以反应体内铁过载情况。因此,本 文对铁过载、LIC及铁过载后骨代谢异常进行综述,以期为研究LIC在铁过载后骨代谢异常中的作用 提供一''定的参考。     

Sodium ferric gluconate complex therapy in anemic children on hemodialysis

Pediatric patients with end-stage renal disease undergoing hemodialysis (HD) frequently develop anemia. Administration of recombinant human erythropoietin (rHuEPO) is effective in managing this anemia, although the additional demand for iron often results in iron deficiency. In adult patients undergoing HD, intravenous (IV) iron administration is known to replenish iron stores more effectively than oral iron administration. Nevertheless, IV iron supplementation is underutilized in pediatric patients, possibly because of unproved safety in this population. This international, multicenter study investigated the safety and efficacy of two dosing regimens (1.5 mg kg^–1 and 3.0 mg kg^–1) of sodium ferric gluconate complex (SFGC) therapy, during eight consecutive HD sessions, in iron-deficient pediatric HD patients receiving concomitant rHuEPO therapy. Safety was evaluated in 66 patients and efficacy was evaluated in 56 patients. Significant increases from baseline were observed in both treatment groups 2 and 4 weeks after cessation of SFGC dosing for mean hemoglobin, hematocrit, transferrin saturation, serum ferritin, and reticulocyte hemoglobin content. Efficacy and safety profiles were comparable for 1.5 mg kg^–1 and 3.0 mg kg^–1 SFGC with no unexpected adverse events with either dose. Administration of SFGC was safe and efficacious in the pediatric HD population. Given the equivalent efficacy of the two doses, an initial dosing regimen of 1.5 mg kg^–1 is recommended for pediatric HD patients.An erratum to this article can be found at The Ferrlecit Pediatric Study Group is a co-author of this paper     

Iron deficiency is highly prevalent among candidates for metabolic surgery and may affect perioperative outcomes

BackgroundThe presence of chronic low-grade inflammation, commonly identified in patients with severe obesity, alters iron homeostasis and indicators of iron status, fostering the development of updated guidelines for the diagnosis of iron deficiency (ID). Current recommended diagnostic thresholds for ID in obesity derived from expert opinion include a ferritin level of <30 ng/mL and/or transferrin saturation (TSAT) < 20%. Earlier studies of ID among candidates for metabolic surgery using low levels of ferritin or iron as diagnostic thresholds demonstrated a prevalence of 5%–20%.ObjectivesUsing the current recommended diagnostic thresholds for ID, this study measures the prevalence of ID in a large cohort of surgical candidates and its relationship to surgical outcomes.SettingGeisinger Medical Center, Danville, Pennsylvania.MethodsThe study cohort included 3,723 patients who underwent pre- operative nutritional assessment which included markers of iron nutrition over the period 2004–2018.ResultsThe cohort included 2,988 women (80.3%) and 735 men (19.7%); body mass index: 49.4 ± 9 kg/m². The diagnosis of ID was based on ferritin level <30 ng/mL (true ID) and/or TSAT < 20% representing a combination of true ID and inflammation (serum ferritin ≥ 30 ng/mL and TSAT < 20%). A total of 399 patients (10.8%) were anemic. A serum ferritin level of < 30 ng/mL was found in 488 patients (13%; 481 women and 7 men). Of these, 122 patients (25.2%) were also anemic. An additional 1,204 had serum ferritin ≥ 30 ng/mL and TSAT < 20%. Overall, 1,692 patients (45.4%) in this cohort had laboratory evidence of ID by current criteria that adjusts for the very high prevalence of inflammation. Men with serum ferritin levels ≥30 ng/mL with TSAT < 20% had an increased surgical length of stay.ConclusionThe prevalence of ID among surgical candidates (45.4%) is more than twice that identified as ID in earlier studies. ID was commonly identified in the absence of anemia. The most severe ID was found in those with a serum ferritin level <30 ng/mL and TSAT < 20%. ID in the presence of inflammation is often unrecognized and has implications regarding surgical outcomes after metabolic surgery.     

Iron therapy for renal anemia: how much needed,how much harmful?

Iron deficiency is the most common cause of hyporesponsiveness to erythropoiesis-stimulating agents (ESAs) in end-stage renal disease (ESRD) patients. Iron deficiency can easily be corrected by intravenous iron administration, which is more effective than oral iron supplementation, at least in adult patients with chronic kidney disease (CKD). Iron status can be monitored by different parameters such as ferritin, transferrin saturation, percentage of hypochromic red blood cells, and/or the reticulocyte hemoglobin content, but an increased erythropoietic response to iron supplementation is the most widely accepted reference standard of iron-deficient erythropoiesis. Parenteral iron therapy is not without acute and chronic adverse events. While provocative animal and in vitro studies suggest induction of inflammation, oxidative stress, and kidney damage by available parenteral iron preparations, several recent clinical studies showed the opposite effects as long as intravenous iron was adequately dosed. Thus, within the recommended international guidelines, parenteral iron administration is safe. Intravenous iron therapy should be withheld during acute infection but not during inflammation. The integration of ESA and intravenous iron therapy into anemia management allowed attainment of target hemoglobin values in the majority of pediatric and adult CKD and ESRD patients.     

Anaphylactoid reaction to intravenous sodium ferric gluconate complex during pregnancy

We report the first case of a severe anaphylactic or anaphylactoid reaction to sodium ferric gluconate complex in a pregnant patient. Sodium ferric gluconate complex is felt to be one of the safest forms of iron therapy during pregnancy. This case highlights the need for extreme caution and vigilance in pregnant patients receiving any type of parenteral iron therapy.     

口服生血宁与静脉用蔗糖铁在肾性贫血患者维持治疗期的临床观察

目的观察口服生血宁与静脉用蔗糖铁在肾性贫血维持期治疗上的疗效差别。方法回顾性分析2013年1月至2015年9月广东省肇庆市第一人民医院肾内科共13例血红蛋白在100~130 g/L的维持性血液透析患者,将其分为生血宁组(7例)及蔗糖铁组(6例),分别收集2组患者基线资料(性别、年龄、干体质量等)。生血宁组以生血宁片0.5 g,每日3次口服治疗;蔗糖铁组以蔗糖铁100 mg,每周1次静脉输注,促红细胞生成素等治疗按照常规进行。治疗3个月后,分别收集2组患者贫血相关指标(血清铁、铁蛋白、总铁结合力、血红蛋白等)、炎症相关指标(超敏C反应蛋白)及透析充分性指标(血肌酐、血钙、血磷等),分别对比2组间及2组治疗前、后上述指标的差别。结果治疗前2组间各指标无明显差别。治疗后生血宁组血红蛋白水平为(116.57±12.21)g/L,蔗糖铁组血红蛋白水平为(106.00±15.36)g/L,2组差异无统计学意义(P=0.194)。治疗后生血宁组血清铁水平为(14.70±5.30)μmol/L,蔗糖铁组血清铁水平为(6.25±2.41)μmoL/L。治疗后生血宁组转铁蛋白饱和度为(O.45±0.20),蔗糖铁组转铁蛋白饱和度为(0.36±0.18)。治疗后生血宁组Hs-CRP水平中位数为2.07 ng/ml,蔗糖铁组Hs-CRP水平中位数为7.95 ng/ml,2组差异具有统计学意义(P0.05),其他指标无明显差异。结论口服生血宁与静脉用蔗糖铁在肾性贫血维持期治疗上疗效相当,其铁代谢指标优于静脉铁剂,且静脉用蔗糖铁组超敏C反应蛋白水平增高。     

Critical role of iron overload in the increased susceptibility of haemodialysis patients to bacterial infections. Beneficial effects of desferrioxamine

Iron overload, which is a common complication in haemodialysis patients, is known to enhance bacterial growth and virulence, and to alter phagocytosis. We reviewed the data of 61 haemodialysed patients to clarify the clinical relevance of iron status to the risk of bacterial infection. Increased concentrations of serum ferritin were associated with a greater infection rate (P less than 0.0025), which was already true for ferritin values between 500 and 1000 micrograms/l (P less than 0.025). Furthermore, in 21 iron-overloaded patients treated with an iron-chelator (desferrioxamine), the infection rate decreased from 1/19 patient-months to 1/112 (P less than 0.005), and returned to previous values when desferrioxamine was stopped. Our results demonstrate the importance of haemosiderosis in the increased susceptibility of haemodialysed patients to infections; this susceptibility is decreased by desferrioxamine therapy, which probably acts by restoring phagocytosis and reducing the bioavailability of iron for pathogens.     

Soft tissue calcification induced by iron complexes

Summary Complexed iron (III) induces a local calcification of soft tissues in mice that is strongly dependent upon the nature of the complexing molecule. Ferric lactate is much more effective in inducing calcification than iron dextran.