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1.
Programmed cell death in intervertebral disc degeneration 总被引:6,自引:0,他引:6
Zhao CQ Jiang LS Dai LY 《Apoptosis : an international journal on programmed cell death》2006,11(12):2079-2088
Intervertebral disc (IVD) degeneration is largely a process of destruction and failure of the extracellular matrix (ECM),
and symptomatic IVD degeneration is thought to be one of the leading causes of morbidity or life quality deterioration in
the elderly. To date, however, the mechanism of IVD degeneration is still not fully understood. Cellular loss from cell death
in the process of IVD degeneration has long been confirmed and considered to contribute to ECM degradation, but the causes
and the manners of IVD cell death remain unclear. Programmed cell death (PCD) is executed by an active cellular process and
is extensively involved in many physiological and pathological processes, including embryonic development and human degenerative
diseases. Thus, the relationship between PCD and IVD degeneration has become a new research focus of interest in recent years.
By reviewing the available literature concentrated on PCD in IVD and discussing the methodology of detecting PCD in IVD cells,
its inducing factors, the relationship of cell death to ECM degradation, and the potential therapy for IVD degeneration by
modulation of PCD, we conclude that IVD cells undergo PCD via different signal transduction pathways in response to different
stimuli, that PCD may play a role in the process of IVD degeneration, and that modulation of PCD might be a potential therapeutic
strategy for IVD degeneration. 相似文献
2.
Batch cultures of photoautotrophic cell suspensions of Chenopodiumrubrum L., growing in an inorganic medium on CO2 under a daily balanced light–dark regime of 16 : 8 h could be maintained for approximately 100 d without subcultivation.
The long-lived cultures showed an initial cell division phase of 4 weeks, followed by a stationary phase of another 4 weeks,
after which ageing and progressive cell death reduced the number of living cells and the cultures usually expired after another
3–4 weeks. These developmental phases of the cell culture were characterised with respect to photosynthetic performance, dark
respiration, content of phytohormones and capacity of cell division. Cell division of the majority of the cells finished in
the G1- or G0-phase of the cell cycle, caused by a pronounced decline in the endogenous levels of auxin and cytokinins. Supply
of these growth factors to resting cells resulted in resumption of cytokinesis, at least by some of the cells. However, responsiveness
to the phytohomones declined during the stationary phase, and subcultivation was no longer possible beyond day 60 when the
phases of ageing and death commenced. Ageing was characterised by a further decline in the photosynthetic capacity of the
cells, by a climacteric enhancement of dark respiration, but also by a slight increase in the level of IAA and cytokinins
concomitant with a decrease in ethylene. Similarities and differences between the development of batch-cultured photoautotrophic
cells of C. rubrum and that of a leaf are discussed with respect to using the cell culture as a model for a leaf.
Received: 30 April 1999 / Accepted: 21 August 1999 相似文献
3.
Chemical-induced apoptotic cell death in tomato cells: involvement of caspase-like proteases 总被引:16,自引:0,他引:16
A new system to study programmed cell death in plants is described. Tomato (Lycopersicon esculentum Mill.) suspension cells were induced to undergo programmed cell death by treatment with known inducers of apoptosis in mammalian
cells. This chemical-induced cell death was accompanied by the characteristic features of apoptosis in animal cells, such
as typical changes in nuclear morphology, the fragmentation of the nucleus and DNA fragmentation. In search of processes involved
in plant apoptotic cell death, specific enzyme inhibitors were tested for cell-death-inhibiting activity. Our results showed
that proteolysis plays a crucial role in apoptosis in plants. Furthermore, caspase-specific peptide inhibitors were found
to be potent inhibitors of the chemical-induced cell death in tomato cells, indicating that, as in animal systems, caspase-like
proteases are involved in the apoptotic cell death pathway in plants.
Received: 5 August 1999 / Accepted: 14 March 2000 相似文献
4.
Simon R Dunn John C BythellMartin D.A Le Tissier William J BurnettJeremy C Thomason 《Journal of experimental marine biology and ecology》2002,272(1):29-53
Different cell death pathways were investigated during bleaching in the sea anemone Aiptasia sp. in response to hyperthermic treatment. Using a suite of techniques, (haematoxylin and eosin staining of paraffin wax-embedded tissue sections, in-situ end labelling (ISEL) of fragmented DNA, agarose gel electrophoresis electron microscopy) both necrotic and programmed cell death (PCD) activity were indicated. After a treatment period of 4 days, the host endoderm tissues underwent necrotic cell death. This was indicated by widespread cellular degradation, dilation of cell cytoplasm and organelles, cell swelling and rupture, irregular pyknotic condensation of nuclear chromatin, and abundant cell debris. Host cell necrosis was associated with the release of zooxanthellae with a normal, healthy appearance into the coelenteron. Longer periods of hyperthermic treatment (7 days) were correlated with further animal cell degradation and the in-situ degradation of zooxanthellae remaining within the degraded endoderm. Within the same degraded endoderm tissue, the degradation of zooxanthellae resulted from two forms of cell death occurring simultaneously, which were identified as programmed cell death and cell necrosis. Programmed cell death of zooxanthellae was characterised by condensation of the cytoplasm and organelles, cell shrinkage, formation of accumulation bodies at the periphery of the cell wall, and DNA fragmentation. Cell necrosis of zooxanthellae was characterised by dilation of the cytoplasm and organelles, cell swelling and lysis, dispersion of cell component debris, and DNA fragmentation. The existence of a programmed cell death pathway within zooxanthellae is important to the understanding of coral bleaching events, raising interesting questions regarding the evolution of this process and the activation of the cellular trigger mechanisms involved. 相似文献
5.
We discuss a dynamical mathematical model to explain cell wall architecture in plant cells. The highly regular textures observed
in cell walls reflect the spatial organisation of the cellulose microfibrils (CMFs), the most important structural component
of cell walls. Based on a geometrical theory proposed earlier [A. M. C. Emons, Plant, Cell and Environment
17, 3–14 (1994)], the present model describes the space-time evolution of the density of the so-called rosettes, the CMF synthesizing
complexes. The motion of these rosettes in the plasma membrane is assumed to be governed by an optimal packing constraint
on the CMFs plus adherent matrix material, that couples the direction of motion, and hence the orientation of the CMF being
deposited, to the local density of rosettes. The rosettes are created inside the cell in the endoplasmatic reticulum and reach
the cell-membrane via vesicles derived from Golgi-bodies. After being inserted into the plasma membrane they are assumed to
be operative for a fixed, finite lifetime. The plasma membrane domains within which rosettes are activated are themselves
also supposed to be mobile. We propose a feedback mechanism that precludes the density of rosettes to rise beyond a maximum
dictated by the geometry of the cell. The above ingredients lead to a quasi-linear first order PDE for the rosette-density.
Using the method of characteristics this equation can be cast into a set of first order ODEs, one of which is retarded. We
discuss the analytic solutions of the model that give rise to helicoidal, crossed polylamellate, helical, axial and random
textures, since all cell walls are composed of (or combinations of) these textures.
Received: 10 July 1999 / Revised version: 7 June 2000 / Published online: 16 February 2001 相似文献
6.
7.
Programmed cell death of tracheary elements as a paradigm in plants 总被引:26,自引:0,他引:26
Fukuda H 《Plant molecular biology》2000,44(3):245-253
Plant development involves various programmed cell death (PCD) processes. Among them, cell death occurring during differentiation of procambium into tracheary elements (TEs), which are a major component of vessels or tracheids, has been studied extensively. Recent studies of PCD during TE differentiation mainly using an in vitro differentiation system of Zinnia have revealed that PCD of TEs is a plant-specific one in which the vacuole plays a central role. Furthermore, there are recent findings of several factors that may initiate PCD of TEs and that act at autonomous degradation of cell contents. Herein I summarize the present knowledge about cell death program during TE differentiation as an excellent example of PCD in plants. 相似文献
8.
Xi-Min Hu Qi Zhang Rui-Xin Zhou Yan-Lin Wu Zhi-Xin Li Dan-Yi Zhang Yi-Chao Yang Rong-Hua Yang Yong-Jun Hu Kun Xiong 《World journal of stem cells》2021,13(5):386-415
Stem cell-based therapy raises hopes for a better approach to promoting tissue repair and functional recovery. However, transplanted stem cells show a high death percentage, creating challenges to successful transplantation and prognosis. Thus, it is necessary to investigate the mechanisms underlying stem cell death, such as apoptotic cascade activation, excessive autophagy, inflammatory response, reactive oxygen species, excitotoxicity, and ischemia/hypoxia. Targeting the molecular pathways involved may be an efficient strategy to enhance stem cell viability and maximize transplantation success. Notably, a more complex network of cell death receives more attention than one crucial pathway in determining stem cell fate, highlighting the challenges in exploring mechanisms and therapeutic targets. In this review, we focus on programmed cell death in transplanted stem cells. We also discuss some promising strategies and challenges in promoting survival for further study. 相似文献
9.
In this paper we give a derivation for the allometric scaling relation between the metabolic rate and the mass of animals and plants. We show that the characteristic scaling exponent of 3/4 occurring in this relation is a result of the distribution of sources and sinks within the living organism. We further introduce a principle of least mass and discuss the kind of flows that arise from it. 相似文献
10.
Lentini A Provenzano B Caraglia M Shevchenko A Abbruzzese A Beninati S 《Amino acids》2008,34(2):251-256
Summary. Previously published evidences highlighted the effect of transglutaminase (TG, EC 2.3.2.13) activation on the reduction of
the in vitro adhesive and invasive behaviour of murine B16-F10 melanoma cells, as well as in vivo. Here, we investigated the
influence of spermidine (SPD) incorporation by TG into basement membrane components i.e. laminin (LN) or Matrigel (MG), on
the adhesion and invasion of B16-F10 melanoma cells by these TG/SPD-modified substrates. The adhesion assays showed that cell
binding to the TG/SPD-modified LN was reduced by 30%, when compared to untreated LN, whereas the reduction obtained using
TG/SPD-modified MG was 35%. Similarly, tumor cell invasion by the Boyden chamber system through TG/SPD modified LN or MG was
respectively reduced by 45%, and by 69%. Evaluation of matrix metalloproteinase (gelatinases MMP-2 and MMP-9) activities by
gel-zymography showed that MMP-2 activity was unaffected, while MMP-9 activity was reduced by about 32% using TG/SPD-modified
substrate. These results strongly suggest that the observed antiinvasive effect of TG activation in the host may be ascribed
to the covalent incorporation of polyamines, which led to the post-translational modification of some components of the cell
basement membrane. This modification may interfere with the metastatic property of melanoma cells, affecting the proteolytic
activity necessary for their migration and invasion activities.
Authors’ address: Simone Beninati, Department of Biology, University of Rome “Tor Vergata”, Via della Ricerca Scientifica,
I-00133 Rome, Italy 相似文献
11.
Programmed cell death (PCD) in plants is a crucial componentof development and defence mechanisms. In animals, differenttypes of cell death (apoptosis, autophagy, and necrosis) havebeen distinguished morphologically and discussed in these morphologicalterms. PCD is largely used to describe the processes of apoptosisand autophagy (although some use PCD and apoptosis interchangeably)while necrosis is generally described as a chaotic and uncontrolledmode of death. In plants, the term PCD is widely used to describemost instances of death observed. At present, there is a vastarray of plant cell culture models and developmental systemsbeing studied by different research groups and it is clear fromwhat is described in this mass of literature that, as with animals,there does not appear to be just one type of PCD in plants.It is fundamentally important to be able to distinguish betweendifferent types of cell death for several reasons. For example,it is clear that, in cell culture systems, the window of timein which PCD is studied by different groups varieshugely and this can have profound effects on the interpretationof data and complicates attempts to compare different researcher'sdata. In addition, different types of PCD will probably havedifferent regulators and modes of death. For this reason, inplant cell cultures an apoptotic-like PCD (AL-PCD) has beenidentified that is fairly rapid and results in a distinct corpsemorphology which is visible 4–6 h after release of cytochromec and other apoptogenic proteins. This type of morphology, distinctfrom autophagy and from necrosis, has also been observed inexamples of plant development. In this review, our model systemand how it is used to distinguish specifically between AL-PCDand necrosis will be discussed. The different types of PCD observedin plants will also be discussed and the importance of distinguishingbetween different forms of cell death will be highlighted. Key words: Apoptosis, apoptosis-like programmed cell death (AL-PCD), Arabidopsis, autophagy, mitochondria, necrosis, programmed cell death (PCD)
Received 5 June 2007; Revised 13 September 2007 Accepted 20 September 2007 相似文献
12.
Gunawardena AH 《Journal of experimental botany》2008,59(3):445-451
The use of programmed cell death (PCD) to remodel plants at the cellular, tissue, and organ levels is particularly fascinating and occurs in such processes as tracheary element differentiation, lysigenous aerenchyma formation, development of functionally unisexual flowers from bisexual floral primordia, and leaf morphogenesis. The formation of complex leaf shape through the use of PCD is a rare event across vascular plants and occurs only in a few species of Monstera and related genera, and in the lace plant (Aponogeton madagascariensis). During early development, the lace plant leaf forms a pattern of equidistantly positioned perforations across the surface of the leaf, giving it a lattice-like appearance. Due to the accessibility and predictability of this process, the lace plant provides highly suitable material for the study of developmentally regulated PCD in plants. A sterile lace plant culture system has been successfully established, providing material free of micro-organisms for experimental study. The potential role of ethylene and caspase-like activity in developmentally regulated PCD in the lace plant is currently under investigation, with preliminary results indicating that both may play a role in the cell death pathway. 相似文献
13.
Summary. The in vitro and in vivo effects of two flavonons, naringenin (NG) and hesperitin (HP) on the proliferation rate of highly metastatic murine B16-F10
melanoma cell were investigated. NG or HP treatment of melanoma cells produced a remarkable reduction of cell proliferation,
paralleled with both the lowering of the intracellular levels of polyamine, spermidine and spermine and the enhancement of
transglutaminase (TGase, EC 2.3.2.13) activity. Orally administered NG or HP in C57BL6/N mice inoculated with B16-F10 cells
affected the pulmonary invasion of melanoma cells in an in vivo metastatic assay. The number of lung metastases detected by a computerized image analyzer was reduced, compared to untreated
animals, by about 69% in NG-treated mice and by about 36% in HP-treated mice. Survival studies showed that 50% of the NG-treated
animals died 38 ± 3.1 days after tumor cell injection (control group: 18 ± 1.5 days) and HP-treated mice died 27 ± 2.3 days
after cell inoculation. Taken together, these findings provide further evidences for the potential anticancer properties of
dietary flavonoids as chemopreventive agents against malignant melanoma. 相似文献
14.
Summary. The effect of different doses of cadmium and copper was studied in relation to growth and polyamine (Pas) metabolism in shoots
of sunflower plants. Cadmium accumulated to higher levels than copper and shoot length was reduced by 0.5 and 1 mM Cd, but
only by 1 mM Cu. At 1 mM of Cd or Cu, Put content increased 270% and 160% with Cd2+ and Cu2+, respectively. Spermidine (Spd) was modified only by 1 mM Cd, while spermine (Spm) declined after seeds germinated, increasing
thereafter but only with 1 mM Cd or Cu (273% over the controls for Cd and 230% for Cu at day 16). Both ADC and ODC activities
were increased by 1 mM Cd, whereas 1 mM Cu enhanced ADC activity, but reduced ODC activity at every concentration used. The
role of Pas as markers of Cd or Cu toxicity is discussed. 相似文献
15.
The pathogenesis-related accumulation of superoxide radical anions (O·−
2) and hydrogen peroxide (H2O2) was comparatively analyzed in a barley line (Hordeum vulgare L. cv Sultan-5) carrying the powdery mildew (Blumeria graminis f.sp. hordei, Speer, Bgh) resistance gene Mla12, and in susceptible mutants defective in Mla12 or in genes “required for Mla12-specified disease resistance” (Rar1 and Rar2). In-situ localization of reactive oxygen intermediates was performed both by microscopic detection of azide-insensitive
nitroblue tetrazolium (NBT) reduction or diaminobenzidine (DAB) polymerization, and by an NBT-DAB double-staining procedure.
The Mla12-mediated hypersensitive cell death occurred either in attacked epidermal cells or adjacent mesophyll cells of wild-type plants.
Whole-cell H2O2 accumulation was detected in dying cells, while O·−
2 emerged in adjacent cells. Importantly, all susceptible mutants lacked these reactions. An oxalate oxidase, which is known
to generate H2O2 and has been implicated in barley resistance against the powdery mildew fungus, was not differentially expressed between
the wild type and all mutants. The results demonstrate that the Rar1 and Rar2 gene products, which are control elements of R-gene-mediated programmed cell death, also control accumulation of reactive oxygen intermediates but not the pathogenesis-related
expression of oxalate oxidase.
Received: 7 January 2000 / Accepted: 2 June 2000 相似文献
16.
Maraschin Sde F Gaussand G Pulido A Olmedilla A Lamers GE Korthout H Spaink HP Wang M 《Planta》2005,221(4):459-470
Androgenesis represents one of the most fascinating examples of cell differentiation in plants. In barley, the conversion of stressed uninucleate microspores into embryo-like structures is highly efficient. One of the bottlenecks in this process is the successful release of embryo-like structures out of the exine wall of microspores. In the present work, morphological and biochemical studies were performed during the transition from multicellular structures to globular embryos. Exine wall rupture and subsequent globular embryo formation were observed only in microspores that divided asymmetrically. Independent divisions of the generative and the vegetative nuclei gave rise to heterogeneous multicellular structures, which were composed of two different cellular domains: small cells with condensed chromatin structure and large cells with normal chromatin structure. During exine wall rupture, the small cells died and their death marked the site of exine wall rupture. Cell death in the small cell domain showed typical features of plant programmed cell death. Chromatin condensation and DNA degradation preceded cell detachment and cytoplasm dismantling, a process that was characterized by the formation of vesicles and vacuoles that contained cytoplasmic material. This morphotype of programmed cell death was accompanied by an increase in the activity of caspase-3-like proteases. The orchestration of such a death program culminated in the elimination of the small generative domain, and further embryogenesis was carried out by the large vegetative domain. To date, this is the first report to show evidence that programmed cell death takes part in the development of microspore-derived embryos. 相似文献
17.
Debrabant A Lee N Bertholet S Duncan R Nakhasi HL 《International journal for parasitology》2003,33(3):257-267
In multicellular organisms, cellular growth and development can be controlled by programmed cell death (PCD), which is defined by a sequence of regulated events. However, PCD is thought to have evolved not only to regulate growth and development in multicellular organisms but also to have a functional role in the biology of unicellular organisms. In protozoan parasites and in other unicellular organisms, features of PCD similar to those in multicellular organisms have been reported, suggesting some commonality in the PCD pathway between unicellular and multicellular organisms. However, more extensive studies are needed to fully characterise the PCD pathway and to define the factors that control PCD in the unicellular organisms. The understanding of the PCD pathway in unicellular organisms could delineate the evolutionary origin of this pathway. Further characterisation of the PCD pathway in the unicellular parasites could provide information regarding their pathogenesis, which could be exploited to target new drugs to limit their growth and treat the disease they cause. 相似文献
18.
Overexpressed transglutaminase 5 triggers cell death 总被引:1,自引:0,他引:1
Summary. Transglutaminases are a class of nine different proteins involved in many biological phenomena such as differentiation, tissue repair, endocytosis. Transglutaminase 5 was originally cloned from skin keratinocytes, and a partial biochemical characterization showed its involvment in skin differentiation. Here we demonstrate that transglutaminase 5 is able to induce cell death when intracellularly overexpressed. Transfected cells show enzymatic activity, as demonstrated by fluoresceincadaverine staining. Transfected cells died due to the formation of hypodiploid DNA content, indicating the induction of cell death under these pharmacological conditions. We also show that the primary sequence of transglutaminase 5 contains GTP binding domains which are similar to those in transglutaminase 2. This raises the possibility that transglutaminase 5 is regulated by GTP in a similar fashion to transglutaminase 2. 相似文献
19.
A microsomal preparation from suspension-cultured potato stem cells (Solanum tuberosum L. cv. AZY) was incubated with [14C]acetyl-CoA resulting in a precipitable radiolabeled product. Analysis of the product revealed that it consisted mostly of
acetylated proteins and cell wall polysaccharides, including xyloglucan, homogalacturonan and rhamnogalacturonan I. Thus,
acetyl-CoA is a donor-substrate for the O-acetylation of wall polysaccharides. A rhamnogalacturonan acetylesterase was used to develop an assay to measure and characterize
rhamnogalacturonan O-acetyl transferase activity in the microsomal preparation. Using this assay, it was shown that the transferase activity was
highest during the linear growth phase of the cells, had a pH-optimum at pH 7.0, a temperature optimum at 30 °C, an apparent
K
m of 35 μM and an apparent V
max of 0.9 pkat per mg protein. Further analysis of the radiolabeled acetylated product revealed that it had a molecular mass
>500 kDa.
Received: 3 July 1999; Accepted: 27 September 1999 相似文献
20.
Apoptosis: Programmed cell death in health and disease 总被引:3,自引:0,他引:3
Apoptosis is a normal physiological cell death process of eliminating unwanted cells from living organisms during embryonic and adult development. Apoptotic cells are characterised by fragmentation of nuclear DNA and formation of apoptotic bodies. Genetic analysis revealed the involvement of many death and survival genes in apoptosis which are regulated by extracellular factors. There are multiple inducers and inhibitors of apoptosis which interact with target cell specific surface receptors and transduce the signal by second messengers to programme cell death. The regulation of apoptosis is elusive, but defective regulation leads to aetiology of various ailments. Understanding the molecular mechanism of apoptosis including death genes, death signals, surface receptors and signal pathways will provide new insights in developing strategies to regulate the cell survival/death. The current knowledge on the molecular events of apoptotic cell death and their significance in health and disease is reviewed. 相似文献