scholarly journals Effect of in vitro and in vivo induction of polyethelene glycol-mediated osmotic stress on hybrid taro (Colocasia esculenta (L.) Schott)

2006 ◽  
pp. 1-11 ◽  
Author(s):  
Manas Ranjan Sahoo ◽  
Madhumita DasGupta ◽  
Archana Mukherjee

Taro hybrid TSL (Topi X Satasankha), along with its parental lines, was evaluated for stress tolerance under in vitro and in vivo polyethelene glycol (PEG) -mediated osmotic stress conditions. Aseptic cultures were raised in vitro under control and PEG-mediated stress conditions. Stress index for survival and growth parameters like rooting ability in cultures and number of leaves produced per plantlet revealed the better response of hybrid lineTSL than its parental lines. The plantlets were hardened and transferred to pots for evaluation of morpho-physico-biochemical parameters under PEG-mediated osmotic stress conditions. Significant variations were observed in stress index for plant height. number of leaves, leaf area, % relative water content (RWC), chlorophyll stability mdex (CSI), % injury by dessication and yield. Decline in biochemical traits like protein content but increase in catalase and peroxidase activities was observed under the osmotic stress conditions. Less variation in morpho-physico-biochemical characters were recorded in TSL under stress conditions as compared to its parents. The hybrid line-TSL showed tolerance to osmotic stress with a minimum yield reduction. TSL can be used for the future breeding program for the development of drought tolerant lines and can become the source of favorable genes for drought tolerance in taro.

Author(s):  
Fatima Aerts-Kaya

: In contrast to their almost unlimited potential for expansion in vivo and despite years of dedicated research and optimization of expansion protocols, the expansion of Hematopoietic Stem Cells (HSCs) in vitro remains remarkably limited. Increased understanding of the mechanisms that are involved in maintenance, expansion and differentiation of HSCs will enable the development of better protocols for expansion of HSCs. This will allow procurement of HSCs with long-term engraftment potential and a better understanding of the effects of the external influences in and on the hematopoietic niche that may affect HSC function. During collection and culture of HSCs, the cells are exposed to suboptimal conditions that may induce different levels of stress and ultimately affect their self-renewal, differentiation and long-term engraftment potential. Some of these stress factors include normoxia, oxidative stress, extra-physiologic oxygen shock/stress (EPHOSS), endoplasmic reticulum (ER) stress, replicative stress, and stress related to DNA damage. Coping with these stress factors may help reduce the negative effects of cell culture on HSC potential, provide a better understanding of the true impact of certain treatments in the absence of confounding stress factors. This may facilitate the development of better ex vivo expansion protocols of HSCs with long-term engraftment potential without induction of stem cell exhaustion by cellular senescence or loss of cell viability. This review summarizes some of available strategies that may be used to protect HSCs from culture-induced stress conditions.


2017 ◽  
Vol 27 (2) ◽  
pp. 161-169 ◽  
Author(s):  
Lidiia Samarina ◽  
Valentina Malyarovskaya ◽  
Yulija Abilfazova ◽  
Natalia Platonova ◽  
Kristina Klemeshova ◽  
...  

Structural and physiological responses of chrysanthemum to repeated osmotic stress were studied. Plants were cultured for 2 weeks (for each stress1 and stress 2) on half MS supplemented with mannitol 100 mM (Treatment I) and 200 mM (Treatment II). First stress inhibited growth parameters stronger than second stress in treatment I. In treatment II both stress events strongly inhibited growth parameters of micro‐shoots. Proline content exceeded control 6 ‐ 8 times after 1st stress, and 2 ‐ 5 times after the 2nd stress in treatments I and II, respectively. Soluble protein was accumulated in leaves during both stress exposures, and 2 ‐ 2.5 times exceeded control after the 2nd stress. Relative water content in both treatments increased after the 2nd stress exposure. In treatment II chlorophyll а and carotenoids contents were 8.78 and 4.62 mg/g comparing to control (4.21 and 2.25 mg/g, respectively) after the 1st stress. But after the 2nd stress there was no difference with control.Plant Tissue Cult. & Biotech. 27(2): 161-169, 2017 (December)


2021 ◽  
Vol 22 (9) ◽  
pp. 4678
Author(s):  
Sepideh Parvanian ◽  
Hualian Zha ◽  
Dandan Su ◽  
Lifang Xi ◽  
Yaming Jiu ◽  
...  

Mechanical stress following injury regulates the quality and speed of wound healing. Improper mechanotransduction can lead to impaired wound healing and scar formation. Vimentin intermediate filaments control fibroblasts’ response to mechanical stress and lack of vimentin makes cells significantly vulnerable to environmental stress. We previously reported the involvement of exosomal vimentin in mediating wound healing. Here we performed in vitro and in vivo experiments to explore the effect of wide-type and vimentin knockout exosomes in accelerating wound healing under osmotic stress condition. Our results showed that osmotic stress increases the size and enhances the release of exosomes. Furthermore, our findings revealed that exosomal vimentin enhances wound healing by protecting fibroblasts against osmotic stress and inhibiting stress-induced apoptosis. These data suggest that exosomes could be considered either as a stress modifier to restore the osmotic balance or as a conveyer of stress to induce osmotic stress-driven conditions.


age ◽  
2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Charles Hunt Walne ◽  
Annabeth Gaudin ◽  
W. Brien Henry ◽  
Kambham Raja Reddy

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Andra-Diana Andreicut ◽  
Alina Elena Pârvu ◽  
Augustin Cătălin Mot ◽  
Marcel Pârvu ◽  
Eva Fischer Fodor ◽  
...  

Oxidative stress and inflammation are interlinked processes. The aim of the study was to perform a phytochemical analysis and to evaluate the antioxidant and anti-inflammatory activities of ethanolic Mahonia aquifolium flower (MF), green fruit (MGF), and ripe fruit (MRF) extracts. Plant extract chemical composition was evaluated by HLPC. A DPPH test was used for the in vitro antioxidant activity. The in vivo antioxidant effects and the anti-inflammatory potential were tested on a rat turpentine oil-induced inflammation, by measuring serum nitric oxide (NOx) and TNF-alpha, total oxidative status (TOS), total antioxidant reactivity (TAR), oxidative stress index (OSI), 3-nitrothyrosine (3NT), malondialdehyde (MDA), and total thiols (SH). Extracts were administrated orally in three dilutions (100%, 50%, and 25%) for seven days prior to inflammation. The effects were compared to diclofenac. The HPLC polyphenol and alkaloid analysis revealed chlorogenic acid as the most abundant compound. All extracts had a good in vitro antioxidant activity, decreased NOx, TOS, and 3NT, and increased SH. TNF-alpha was reduced, and TAR increased only by MF and MGF. MDA was not influenced. Our findings suggest that M. aquifolium has anti-inflammatory and antioxidant effects that support the use in primary prevention of the inflammatory processes.


2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
Lixia Ji ◽  
Lixia Cheng ◽  
Zhihong Yang

Objective.Lens osmotic expansion, provoked by overactivated aldose reductase (AR), is the most essential event of sugar cataract. Chloride channel 3 (Clcn3) is a volume-sensitive channel, mainly participating in the regulation of cell fundamental volume, and P-glycoprotein (P-gp) acts as its modulator. We aim to study whether P-gp and Clcn3 are involved in lens osmotic expansion of galactosemic cataract.Methods and Results.In vitro, lens epithelial cells (LECs) were primarily cultured in gradient galactose medium (10–60 mM), more and more vacuoles appeared in LEC cytoplasm, and mRNA and protein levels of AR, P-gp, and Clcn3 were synchronously upregulated along with the increase of galactose concentration. In vivo, we focused on the early stage of rat galactosemic cataract, amount of vacuoles arose from equatorial area and scattered to the whole anterior capsule of lenses from the 3rd day to the 9th day, and mRNA and protein levels of P-gp and Clcn3 reached the peak around the 9th or 12th day.Conclusion. Galactosemia caused the osmotic stress in lenses; it also markedly leads to the upregulations of AR, P-gp, and Clcn3 in LECs, together resulting in obvious osmotic expansion in vitro and in vivo.


2004 ◽  
Vol 3 (6) ◽  
pp. 1544-1556 ◽  
Author(s):  
Jade Mei-Yeh Lu ◽  
Robert J. Deschenes ◽  
Jan S. Fassler

ABSTRACT Yeast Sln1p is an osmotic stress sensor with histidine kinase activity. Modulation of Sln1 kinase activity in response to changes in the osmotic environment regulates the activity of the osmotic response mitogen-activated protein kinase pathway and the activity of the Skn7p transcription factor, both important for adaptation to changing osmotic stress conditions. Many aspects of Sln1 function, such as how kinase activity is regulated to allow a rapid response to the continually changing osmotic environment, are not understood. To gain insight into Sln1p function, we conducted a two-hybrid screen to identify interactors. Mog1p, a protein that interacts with the yeast Ran1 homolog, Gsp1p, was identified in this screen. The interaction with Mog1p was characterized in vitro, and its importance was assessed in vivo. mog1 mutants exhibit defects in SLN1-SKN7 signal transduction and mislocalization of the Skn7p transcription factor. The requirement for Mog1p in normal localization of Skn7p to the nucleus does not fully account for the mog1-related defects in SLN1-SKN7 signal transduction, raising the possibility that Mog1p may play a role in Skn7 binding and activation of osmotic response genes.


2020 ◽  
Vol 14 (2) ◽  
pp. 178-186
Author(s):  
Lisa Novita Arios ◽  
Dwi Suryanto . ◽  
Kiki Nurtjahja . ◽  
Erman Munir .

Assay on ability of endophytic bacteria isolated from peanut to inhibit Sclerotium sp. growth in peanut seedlings.   A study on assay of ability of endophytic bacteria to inhibit Sclerotium sp. in peanut seedling has been done. The bacteria were isolated from peanut healthy plants, while Sclerotium sp. was isolated from infected peanaut plant. Antagonistic assay was conducted by dual culture method.  In vivo assay of inhibiting Sclerotium sp. was conducted by dipping peanut seed in bacterial solution, and planting the seed in soil:compost (3:1) growing media. Six endophytic bacterial isolates showed to inhibit the growth of Sclerotium sp. in vitro. LN1 seemed to inhibit more of Sclerotium sp., while LN5 showed to inhibit less. Two potential isolates LN1 of gram-negative and LN2 of gram-positive using for further study showed to decrease more of dumping off. It also seemed that the isolates increased the seedling height, number of leaves, and dry weight.


Blood ◽  
2010 ◽  
Vol 115 (9) ◽  
pp. 1709-1717 ◽  
Author(s):  
Yan Sun ◽  
Lijian Shao ◽  
Hao Bai ◽  
Zack Z. Wang ◽  
Wen-Shu Wu

Abstract Both extrinsic and intrinsic mechanisms tightly govern hematopoietic stem cell (HSC) decisions of self-renewal and differentiation. However, transcription factors that can selectively regulate HSC self-renewal division after stress remain to be identified. Slug is an evolutionarily conserved zinc-finger transcription factor that is highly expressed in primitive hematopoietic cells and is critical for the radioprotection of these key cells. We studied the effect of Slug in the regulation of HSCs in Slug-deficient mice under normal and stress conditions using serial functional assays. Here, we show that Slug deficiency does not disturb hematopoiesis or alter HSC homeostasis and differentiation in bone marrow but increases the numbers of primitive hematopoietic cells in the extramedullary spleen site. Deletion of Slug enhances HSC repopulating potential but not its homing and differentiation ability. Furthermore, Slug deficiency increases HSC proliferation and repopulating potential in vivo after myelosuppression and accelerates HSC expansion during in vitro culture. Therefore, we propose that Slug is essential for controlling the transition of HSCs from relative quiescence under steady-state condition to rapid proliferation under stress conditions. Our data suggest that inhibition of Slug in HSCs may present a novel strategy for accelerating hematopoietic recovery, thus providing therapeutic benefits for patients after clinical myelosuppressive treatment.


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