铁死亡与心血管疾病的关系及其靶向治疗

铁死亡是一种以细胞内铁过载及脂质代谢异常为特征的程序性细胞死亡方式。关于铁死亡，除了铁代谢、脂质代谢、氧化-抗氧化失调等经典机制外，近年来研究发现，铁蛋白自噬、脂肪自噬、线粒体代谢障碍、核因子E2相关因子2(Nrf2)基因调控、内体分拣转运复合体Ⅲ（ESCRT-Ⅲ）介导的膜修复机制等也参与调控铁死亡；同时，铁死亡参与多种心血管疾病的发生。本文综述了铁死亡相关机制研究进展，分析了其与心肌缺血再灌注损伤、阿霉素的心肌毒性、心力衰竭、动脉粥样硬化和主动脉瓣膜钙化等心血管疾病的关系，并对其靶向治疗相关研究进行总结分析，指出铁死亡有望成为心血管疾病的重要干预靶点，可为心血管疾病的相关药物研究提供参考。     

支链氨基酸氨基转移酶1通过核因子E2相关因子2调节缺氧/复氧损伤相关的心肌细胞铁死亡

目的 研究支链氨基酸转移酶（branched-chain amino acid aminotransferase 1,BCAT1）调节心肌细胞铁死亡和缺氧/复氧损伤的作用及机制。方法 分离Sprague Dawley乳鼠心室肌细胞（neonatal rat ventricular myocytes,NRVMs）并培养。利用腺病毒载体转染NRVMs分别敲低或过表达BCAT1后给予NRVMs缺氧/复氧（hypoxia/reoxygenation,H/R）损伤或给予Erastin诱导其铁死亡。给予核因子E2相关因子2(nuclear factor erythroid 2-related factor-2,NRF2)特异性抑制剂ML385探讨NRF2在BCAT1调节NRVMs铁死亡中的作用。结果 敲低BCAT1表达加重H/R诱导的NRVMs死亡和脂质过氧化,而敲低BCAT1加重损伤的现象可被铁死亡抑制剂Ferr-1基本消除。过表达BCAT1可以减轻H/R和Erastin诱导的心肌细胞死亡和脂质过氧化。过表达BCAT1显著上调NRF2蛋白表达和下游抗氧化应激基因Ho-1、Nqo-1和Trx-1 ...     

铁死亡与骨质疏松的关系研究进展

铁死亡是一种以铁超载和活性氧积累为特征的新型细胞死亡模式。研究发现,细胞铁死亡在骨细胞、成骨细胞及破骨细胞中均有重要作用。铁代谢异常导致细胞内铁积聚,从而促进铁死亡的发生。铁死亡与骨质疏松关系紧密,如高糖高脂通过激活MET L3/ASK1-p38信号通路诱导成骨细胞铁死亡,地塞米松通过p53/SLC7A11/GPX4信号通路促进成骨细胞铁死亡等促进了骨质疏松的发生、发展;而通过调节铁死亡可有效预防和治疗骨质疏松。     

心肌细胞铁死亡及其检测方法

铁死亡是一种新型程序性细胞死亡方式。近年来研究发现，铁死亡在心脏疾病的发生发展中发挥了重要作用。随着心肌细胞铁死亡领域的深入研究，人们对心肌细胞铁死亡检测的精确性和可重复性的关注度日益增加，揭示心肌细胞铁死亡的详细分子机制及开发精确的铁死亡检测方法具有极其重要的指导意义与临床价值。现对目前研究中识别、测量和评估心肌细胞铁死亡的最佳方法加以综述。     

慢性阻塞性肺疾病预后评价指标的研究进展

慢性阻塞性肺疾病有很高的发病率和死亡率。近年来，有关慢性阻塞性肺疾病的预后和死亡预测因子的众多指标成为目前国内外研究的热点。本文通过查阅国内外文献，对反映慢性阻塞性肺疾病预后的指标作一简要综述。     

铁死亡在肝脏疾病中的作用与机制研究进展

[摘要]?铁死亡是近年发现的一种非凋亡形式的程序性细胞死亡方式,其中心环节是铁代谢紊乱导致的胞内脂质过氧化与氧化应激失调。机体内部铁转运系统以及组织细胞的抗氧化系统抑制了铁死亡并维持了生理状态的铁稳态。目前,在多种肝脏疾病中均发现了以脂质过氧化物和活性氧的堆积为特征的铁死亡现象,而铁死亡抑制剂可以有效地抑制铁死亡所致的肝脏损伤。因此,调控铁死亡的发生、发展成为一种新的肝脏疾病潜在治疗策略。本文综述了铁死亡的发生机制以及各种肝脏疾病中铁死亡的研究进展,为探索肝脏疾病的新型治疗方法提供理论基础。     

肝脏疾病细胞铁死亡研究进展*

目的 铁死亡是一种新发现的细胞死亡方式,是由于细胞内铁离子水平异常升高,导致氧化还原失衡,细胞膜发生脂质过氧化,最终细胞膜破裂,导致细胞死亡。目前认为铁死亡的中心环节是铁代谢和活性氧代谢。铁死亡可以影响多种疾病的发生发展过程,例如神经退行性疾病、肿瘤、缺血再灌注损伤、免疫性疾病等。越来越多的研究表明,在多种肝脏疾病的发生发展过程中均出现不同程度的铁超载和脂质活性氧堆积等铁死亡特征。铁死亡可以通过调节细胞内铁离子水平和脂质过氧化程度影响肝脏疾病的进程。本文将针对肝脏疾病发病过程中细胞铁死亡研究进展进行综述。     

铁死亡：腹主动脉瘤防治新靶点?

铁死亡是一种铁依赖性的、非凋亡型的程序性细胞死亡方式,其主要特征是铁代谢紊乱导致细胞内铁超载,通过芬顿反应诱导脂质过氧化,激活铁死亡。铁死亡与诸多疾病相关,其中与腹主动脉瘤的关系近来受到关注。腹主动脉瘤是一种以腹主动脉壁结构破坏、不可逆性扩张为主要特征的退行性病变,其发病机制与氧化应激、炎症反应、血管平滑肌细胞丢失及血管钙化有关。铁死亡可能通过上述途径参与腹主动脉瘤的发生。因此,本文对铁死亡和腹主动脉瘤的致病机制进行综述,为腹主动脉瘤的治疗提供新思路和新靶点。     

中性粒细胞活化和上皮细胞凋亡在急性肺损伤发生中的作用

致病因子一方面诱导肺泡巨噬细胞和上皮细胞产生多种细胞因子和趋化因子,激活中性粒细胞并使其向损伤部位聚集,从而产生炎症因子的瀑布式反应;另一方面激活死亡受体通路Fas-FasL等诱发肺上二皮细胞凋亡,从而引起肺组织损伤.另外,Fas活化后可通过介导肺内炎症介质释放和中性粒细胞聚集进一步加重肺损伤.中性粒细胞活化和上皮细胞凋亡在急性肺损伤的发生过程中起重要作用.     

膀胱癌发病过程中细胞铁死亡的调控机制及其靶向治疗研究进展

铁死亡是一种铁依赖性的脂质过氧化介导的细胞死亡方式，主要特点是细胞内铁和脂质过氧化物的过度积累。铁死亡在肿瘤生长抑制及肿瘤免疫微环境中发挥重要作用。研究发现，铁死亡与膀胱癌的发生发展有关。增加细胞内铁离子、抑制SLC7A11表达、激活p53等可诱导膀胱癌细胞铁死亡，非编码RNA对铁死亡也有一定调控作用。靶向某些铁死亡相关基因或应用某些化合物，能诱导铁死亡，减轻膀胱癌对化疗药物的耐药。深入研究铁死亡作用机制及相关作用靶点，有望开发新的膀胱癌靶向治疗方法，提高治疗效果，改善患者预后。     

Three layer functional model and energy exchange concept of aging process

Relying on a certain degree of abstraction, we can propose that no particular distinction exists between animate or living matter and inanimate matter. While focusing attention on some specifics, the dividing line between the two can be drawn. The most apparent distinction is in the level of structural and functional organization with the dissimilar streams of ‘energy flow’ between the observed entity and the surrounding environment. In essence, living matter is created from inanimate matter which is organized to contain internal intense energy processes and maintain lower intensity energy exchange processes with the environment. Taking internal and external energy processes into account, we contend in this paper that living matter can be referred to as matter of dissipative structure, with this structure assumed to be a common quality of all living creatures and living matter in general. Interruption of internal energy conversion processes and terminating the controlled energy exchange with the environment leads to degeneration of dissipative structure and reduction of the same to inanimate matter, (gas, liquid and/or solid inanimate substances), and ultimately what can be called ‘death.’ This concept of what we call dissipative nature can be extended from living organisms to social groups of animals, to mankind. An analogy based on the organization of matter provides a basis for a functional model of living entities. The models relies on the parallels among the three central structures of any cell (nucleus, cytoplasm and outer membrane) and the human body (central organs, body fluids along with the connective tissues, and external skin integument). This three-part structural organization may be observed almost universally in nature. It can be observed from the atomic structure to the planetary and intergalactic organizations. This similarity is corroborated by the membrane theory applied to living organisms. According to the energy nature of living matter and the proposed functional model, the decreased integrity of a human body's external envelope membrane is a first cause of the structural degradation and aging of the entire organism. The aging process than progresses externally to internally, as in single cell organisms, suggesting that much of the efforts towards the restoration and maintenance of the mechanisms responsible for structural development should be focused accordingly, on the membrane, i.e., the skin. Numerous reports indicate that all parts of the human body, like: bones, blood with blood vessels, muscles, skin, and so on, have some ability for restoration. Therefore, actual revival of not only aging tissue of the human body's membrane, but the entire human body enclosed within, with all internal organs, might be expected. We assess several aging theories within the context of our model and provide suggestions on how to activate the body's own anti-aging mechanisms and increase longevity. This paper presents some analogies and some distinctions that exist between the living dissipative structure matter and inanimate matter, discusses the aging process and proposes certain aging reversal solutions.     

Unusual responses of nocturnal pineal melatonin synthesis and secretion to swimming: Attempts to define mechanisms

Abstract: The effect of swimming at night on rat pineal melatonin synthesis was compared with that of light exposure at night. Rats were forced to swim at 0030 hr (lights out at 2000 hr) and sacrificed by decapitation 15 and 30 min later, immediately after swimming. Other groups of animals were exposed to white light (650μW/cm²) for 15 and 30 min at same time. Swimming caused a rapid and highly significant drop in the melatonin content in the pineal gland; however, the activity of N-acetyltransferase (NAT), the supposed rate limiting enzyme in the melatonin production, was not changed. Despite the drop in pineal melatonin levels, serum concentrations of the indole remained elevated in the rats that swam. In contrast, melatonin levels in the pineal and serum of light exposed rats fell precipitously, accompanied by a significant suppression of NAT activity. Since we anticipated that the strenuous exercise associated with swimming may induce release of artrial natriuretic peptide (ANP) from the heart, which in turn could cause the release of pineal melatonin, in a second study we injected physiological saline intravenously to stretch the cardiac muscle and release ANP. Three milliliters of normal saline was injected during the day into the jugular vein of anesthetized rats that were pretreated with isoproterenol to stimulate pineal melatonin production. Animals were killed 15 min after the saline injection, and pineal NAT activity and pineal melatonin levels were measured. The saline injections caused no alteration in the elevated levels of either NAT or melatonin. These data suggest that the disparity in pineal NAT activity (which was high) and pineal melatonin (which was low), in animals swum at night, may not be caused by ANP which is released during strenuous exercise such as swimming.     

Melatonin and photoperiodic time measurement: Seasonal breeding in the sheep

Abstract: Well-established circadian physiology supports the view that photoperiodic time measurement utilizes the coincidence between the presence of light and a photosensitive phase of a 'biological clock' to alter reproductive status—the so-called external coincidence model of seasonal breeding. In this review, we examine the mechanism whereby photoperiod interacts with presumed suprachiasmatic nuclei activity to allow endogenous melatonin to normally synchronize reproductive activity to the optimal time of year. The Romney Marsh sheep is particularly explored as an experimental model. It is suggested that the on/off activity of seasonal reproduction may be a robust mechanism able to be predictably manipulated by the judicious use of the light/dark cycle and exogenous melatonin, but firmly based on circadian principles.     

Serological survey of HIV and syphilis in pregnant women in Madagascar

Objectives Peripartal transmission of human immunodeficiency virus (HIV) and Treponema pallidum, the causative agent of syphilis, leads to severe consequences for newborns. Preventive measures require awareness of the maternal infection. Although HIV and syphilis testing in Madagascar could be theoretically carried out within the framework of the national pregnancy follow‐up scheme, the required test kits are rarely available at peripheral health centres. In this study, we screened blood samples of pregnant Madagascan women for HIV and syphilis seroprevalence to estimate the demand for systemic screening in pregnancy. Methods Retrospective anonymous serological analysis for HIV and syphilis was performed in plasma samples from 1232 pregnant women that were taken between May and July 2010 in Ambositra, Ifanadiana, Manakara, Mananjary, Moramanga and Tsiroanomandidy (Madagascar) during pregnancy follow‐up. Screening was based on Treponema pallidum haemagglutination tests for syphilis and rapid tests for HIV, with confirmation of positive screening results on line assays. Results Out of 1232 pregnant women, none were seropositive for HIV and 37 (3%) were seropositive for Treponema pallidum. Conclusions Our findings are in line with previous studies that describe considerable syphilis prevalence in the rural Madagascan population. The results suggest a need for screening to prevent peripartal Treponema pallidum transmission, while HIV is still rare. If they are known, Treponema pallidum infections can be easily, safely and inexpensively treated even in pregnancy to reduce the risk of transmission.     

Variabilité des concentrations plasmatiques de l’angiotensinogène et risque d’hypertension artérielle chez le rat transgénique

Aim

Genetic polymorphisms of the human angiotensinogen gene are frequent and may induce up to 30% increase of plasma angiotensinogen concentrations with a blood pressure increase of up to 5 mmHg. Their role for the pathogenesis of human arterial hypertension remains unclear. High plasma angiotensinogen levels could increase the sensitivity to other blood pressure stressors.

Methods

Male transgenic rats with a 9-fold increase of plasma angiotensinogen concentrations and male non-transgenic rats aged 10 weeks were treated or not with NG-Nitro-L-arginine-methyl ester for 3 weeks in their drinking water (n = 3/group). Systolic blood pressure and body weight were measured at baseline and at the end of the study when left ventricular weight and ventricular expression of angiotensin I-converting enzyme and procollagen Iα1 were determined (polymerase chain reaction).

Results

At baseline, transgenic rats had +18 mmHg higher bood pressure and –8% lower body weight compared to non-transgenic rats (P < 0.05) without significant changes for the vehicle groups throughout the study (P > 0.05). NG-Nitro-L-arginine-methyl ester increased blood pressure, left ventricular weight and left ventricular weight indexed for body weight by +41%, +17.6% and +18.6% (P < 0.05) in transgenic and +25%, +5.3% and +6.7% (P > 0.05) in non-transgenic rats compared to untreated animals, respectively. Cardiac gene expression showed no differences between groups (P > 0.05).

Conclusion

Increased plasma angiotensinogen levels may sensitize to additional blood pressure stressors. Our preliminary results point towards an independent role of angiotensinogen in the pathogenesis of human hypertension and associated end-organ damage.     

Morphological and immunocytochemical heterogeneity of cultured pinealocytes from one-week-and two-month-old rats: Planimetric and densitometric investigations

Abstract: In vitro preparations of rat pinealocytes are widely used for biochemical analyses of signal transduction processes. This paper deals with morphological and immunocytochemical features of such preparations. Special attention was paid to the problems of whether pinealocytes represent a heterogeneous cell population and how such heterogeneity may develop during ontogeny. The investigations were performed with cells which were obtained from the pineal organ of one-week-and two-month-old rats, attached to synthetic peptide-coated coverslips or tissue culture chamber slides, and maintained under in vitro conditions overnight. The attached cells were then fixed with paraformaldehyde. These preparations yielded monolayers of spherical cells of different sizes; most cells were isolated, but some of them were aggregated and formed small clusters. On the average, the cells from the one-week-old animals were smaller than the cells from the two-month-old animals. Immunocytochemical demonstration of S-antigen, a pinealocyte-specific marker, showed that the majority of the cells from two-month-old animals were intensely or moderately labelled. Pinealocytes from one-week-old animals were less S-antigen immunoreactive. Only very few cells (less than 1% displayed glial fibrillary acidic protein (GFAP)-immunoreactivity. Planimetric investigations of the cell size and semiquantitative densitometric investigations of the intensity of the S-antigen immunoreaction revealed that (i) pinealocytes kept in vitro form a heterogeneous cell population, and that (ii) this heterogeneity increases during postnatal development from one-week-old to two-month-old animals. Two groups of pinealocytes can be distinguished based on their developmental fate: pinealocytes of one group grow dramatically, but show only a moderate increase in S-antigen immunoreactivity, and pinealocytes of the other group retain their size, but display a distinct increment in S-antigen immunoreacti vitv.     

Effects of pinealectomy and melatonin administration on certain indices of ovarian hyperplasia and/or hypertrophy in rats with both ovaries intact or after unilateral ovariectomy

Abstract: In earlier studies from other laboratories it was shown that melatonin decreased ovarian weight in rats and inhibited compensatory hypertrophy of the remaining ovary after unilateral ovariectomy. This study was designed to examine the influence of melatonin on certain indices of ovarian hyperplasia and/or hypertrophy in adult female rats with both ovaries preserved and with either an intact pineal gland or with the pineal gland removed (pinealectomy, PX) or, finally, in sham-PX animals. Similar studies were conducted on rats after unilateral ovariectomy, referring the examined parameters to the remaining intact ovary. The studies included mitotic activity of granulosa layer cells and corpus luteum cells, ovarian weight, ovarian cross-sectional area, cross-sectional area of the granulosa layer of all the Graafian follicles and the cross-sectional areas of the corpora lutea, visible on the ovarian cross-section. On the basis of results, we conclude that: 1) the effect of PX on the processes of ovarian hyperplasia and hypertrophy may vary; analogously, exogenous melatonin administration may influence ovarian hyperplasia and hypertrophy in different ways; 2) PX and exogenous melatonin may, under certain conditions, exert similar biological effects, even synergistic effects; 3) melatonin inhibits ovarian growth processes, while the effects of PX are variable; 4) the results indicate that in experiments performed on rats, with the use of two control groups, i.e., intact and sham-PX, melatonin effects on these two groups may differ.