Polyamine metabolism in sunflower plants under long-term cadmium or copper stress

Amino Acids ◽  
2006 ◽  
Vol 32 (2) ◽  
pp. 265-275 ◽  
Author(s):  
M. D. Groppa ◽  
M. P. Ianuzzo ◽  
M. L. Tomaro ◽  
M. P. Benavides
Keyword(s):  
Copper Stress ◽  
Polyamine Metabolism

scholarly journals Nicotinamide Nucleotide Transhydrogenase as a Novel Treatment Target in Adrenocortical Carcinoma

Endocrinology ◽  
2018 ◽  
Vol 159 (8) ◽  
pp. 2836-2849 ◽  
Author(s):  
Vasileios Chortis ◽  
Angela E Taylor ◽  
Craig L Doig ◽  
Mark D Walsh ◽  
Eirini Meimaridou ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Adrenocortical Carcinoma ◽  
Reduced Form ◽  
Polyamine Metabolism ◽  
Metabolome Analysis ◽  
Nucleotide Synthesis ◽  
Treatment Target ◽  
Nicotinamide Nucleotide Transhydrogenase ◽  
Response To Chemotherapy

Abstract Adrenocortical carcinoma (ACC) is an aggressive malignancy with poor response to chemotherapy. In this study, we evaluated a potential new treatment target for ACC, focusing on the mitochondrial reduced form of NAD phosphate (NADPH) generator nicotinamide nucleotide transhydrogenase (NNT). NNT has a central role within mitochondrial antioxidant pathways, protecting cells from oxidative stress. Inactivating human NNT mutations result in congenital adrenal insufficiency. We hypothesized that NNT silencing in ACC cells will induce toxic levels of oxidative stress. To explore this, we transiently knocked down NNT in NCI-H295R ACC cells. As predicted, this manipulation increased intracellular levels of oxidative stress; this resulted in a pronounced suppression of cell proliferation and higher apoptotic rates, as well as sensitization of cells to chemically induced oxidative stress. Steroidogenesis was paradoxically stimulated by NNT loss, as demonstrated by mass spectrometry–based steroid profiling. Next, we generated a stable NNT knockdown model in the same cell line to investigate the longer lasting effects of NNT silencing. After long-term culture, cells adapted metabolically to chronic NNT knockdown, restoring their redox balance and resilience to oxidative stress, although their proliferation remained suppressed. This was associated with higher rates of oxygen consumption. The molecular pathways underpinning these responses were explored in detail by RNA sequencing and nontargeted metabolome analysis, revealing major alterations in nucleotide synthesis, protein folding, and polyamine metabolism. This study provides preclinical evidence of the therapeutic merit of antioxidant targeting in ACC as well as illuminating the long-term adaptive response of cells to oxidative stress.

Inhibition of Root Growth and Polyamine Metabolism in Sunflower (Helianthus annuus) Seedlings Under Cadmium and Copper Stress

2008 ◽  
Vol 126 (1-3) ◽  
pp. 246-256 ◽  
Author(s):  
María D. Groppa ◽  
Myriam S. Zawoznik ◽  
María L. Tomaro ◽  
María P. Benavides
Keyword(s):  
Root Growth ◽  
Helianthus Annuus ◽  
Copper Stress ◽  
Polyamine Metabolism

scholarly journals Dissecting Rice Polyamine Metabolism under Controlled Long-Term Drought Stress

PLoS ONE ◽  
2013 ◽  
Vol 8 (4) ◽  
pp. e60325 ◽  
Author(s):  
Phuc Thi Do ◽  
Thomas Degenkolbe ◽  
Alexander Erban ◽  
Arnd G. Heyer ◽  
Joachim Kopka ◽  
...  
Keyword(s):  
Drought Stress ◽  
Polyamine Metabolism

scholarly journals Excess copper induces structural changes in cultured photosynthetic soybean cells

2006 ◽  
Vol 33 (11) ◽  
pp. 1001 ◽  
Author(s):  
María Bernal ◽  
Pilar Sánchez-Testillano ◽  
María del Carmen Risueño ◽  
Inmaculada Yruela
Keyword(s):  
Cell Wall ◽  
Structural Changes ◽  
Copper Tolerance ◽  
Copper Stress ◽  
Induced Response ◽  
Cytoplasmic Vacuole ◽  
Cell Nuclei ◽  
Short Term ◽  
Excess Copper

Soybean [Glycine max (L.) Merr.] cell suspensions have the capacity to develop tolerance to excess copper, constituting a convenient system for studies on the mechanisms of copper tolerance. The functional cell organisation changes observed in these cell cultures after both short-term (stressed cells) and long-term (acclimated cells) exposure to 10 μm CuSO4 are reported from structural, cytochemical and microanalytical approaches. Cells grown in the presence of 10 μm CuSO4 shared some structural features with untreated cells, such as: (i) a large cytoplasmic vacuole, (ii) chloroplasts along the thin layer of cytoplasm, (iii) nucleus in a peripheral location exhibiting circular-shaped nucleolus and a decondensed chromatin pattern, and (iv) presence of Cajal bodies in the cell nuclei. In addition, cells exposed to 10 μm CuSO4 exhibited important differences compared with untreated cells: (i) chloroplasts displayed rounded shape and smaller size with denser-structured internal membranes, especially in copper-acclimated cells; (ii) no starch granules were found within chloroplasts; (iii) the cytoplasmic vacuole was larger, especially after long-term copper exposure; (iv) the levels of citrate and malate increased. Extracellular dark-coloured deposits with high copper content attached at the outer surface of the cell wall were observed only in cells exposed to a short-term copper stress. Structural cell modifications, mainly affecting chloroplasts, accompanied the short-term copper-induced response and were maintained as stable characters during the period of adaptation to excess copper. Vacuolar changes accompanied the long-term copper response. The results indicate that the first response of soybean cells to excess copper prevents its entry into the cell by immobilising it in the cell wall, and after an adaptive period, acclimation to excess copper may be mainly due to vacuolar sequestration.

Polyamine metabolism in sunflower and wheat leaf discs under cadmium or copper stress

Plant Science ◽  
2003 ◽  
Vol 164 (2) ◽  
pp. 293-299 ◽  
Author(s):  
Marı́a D Groppa ◽  
Marı́a P Benavides ◽  
Marı́a L Tomaro
Keyword(s):  
Copper Stress ◽  
Polyamine Metabolism ◽  
Leaf Discs ◽  
Wheat Leaf

scholarly journals Polyamine Metabolism of Potato Seed-Tubers During Long-Term Storage and Early Sprout Development

1989 ◽  
Vol 91 (1) ◽  
pp. 183-189 ◽  
Author(s):  
Loretta J. Mikitzel ◽  
N. Richard Knowles
Keyword(s):  
Polyamine Metabolism ◽  
Potato Seed ◽  
Seed Tubers ◽  
Long Term Storage ◽  
Term Storage

Therapy and prevention for mental health: What if mental diseases are mostly not brain disorders?

2019 ◽  
Vol 42 ◽  
Author(s):  
John P. A. Ioannidis
Keyword(s):  
Mental Health ◽  
Mental Disease ◽  
Brain Disorders ◽  
Social Stressors ◽  
Labor Education ◽  
Mental Diseases ◽  
Long Term Follow Up ◽  
Political Decisions

AbstractNeurobiology-based interventions for mental diseases and searches for useful biomarkers of treatment response have largely failed. Clinical trials should assess interventions related to environmental and social stressors, with long-term follow-up; social rather than biological endpoints; personalized outcomes; and suitable cluster, adaptive, and n-of-1 designs. Labor, education, financial, and other social/political decisions should be evaluated for their impacts on mental disease.

Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

2016 ◽  
Vol 39 ◽  
Author(s):  
Mary C. Potter
Keyword(s):  
Working Memory ◽  
Rapid Serial Visual Presentation ◽  
Language Comprehension ◽  
Short Term Memory ◽  
Visual Presentation ◽  
Long Term Memory ◽  
Short Term ◽  
Term Memory ◽  
Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

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