Osmotic shock or osmotic stress is physiologic dysfunction caused by a sudden change in the solute concentration around a cell, which causes a rapid change in the movement of water across its cell membrane. Under hypertonic conditions - conditions of high concentrations of either salts, substrates or any solute in the supernatant - water is drawn out of the cells through osmosis. This also inhibits the transport of substrates and cofactors into the cell thus “shocking” the cell. Alternatively, under hypotonic conditions - when concentrations of solutes are low - water enters the cell in large amounts, causing it to swell and either burst or undergo apoptosis.[1]
Tonicity Graphic: In isotonic solutions water flows equally into and out of the cell. In hypertonic solutions water flows out of the cell and the cell shrinks. In hypotonic solutions water flows into the cell and the cell grows.
All organisms have mechanisms to respond to osmotic shock, with sensors and signal transduction networks providing information to the cell about the osmolarity of its surroundings;[2] these signals activate responses to deal with extreme conditions.[3] Cells that have a cell wall tend to be more resistant to osmotic shock because their cell wall enables them to maintain their shape.[4] Although single-celled organisms are more vulnerable to osmotic shock, since they are directly exposed to their environment, cells in large animals such as mammals still suffer these stresses under some conditions.[5] Current research also suggests that osmotic stress in cells and tissues may significantly contribute to many human diseases.[6]
In eukaryotes, calcium acts as one of the primary regulators of osmotic stress. Intracellular calcium levels rise during hypo-osmotic and hyper-osmotic stresses.
Calcium plays a large role in the recovery and tolerance for both hyper and hypo-osmotic stress situations. Under hyper-osmotic stress conditions, increased levels of intracellular calcium are exhibited. This may play a crucial role in the activation of second messenger pathways.[7]
One example of a calcium activated second messenger molecule is MAP Kinase Hog-1. It is activated under hyper-osmotic stress conditions[8] and is responsible for an increase in the production of glycerol within the cell succeeding osmotic stress. More specifically, it works by sending signals to the nucleus that activate genes responsible for glycerol production and uptake.[8]
For hypo-osmotic stressedit
Hypo-osmotic stress recovery is largely mediated by the influx and efflux of several ions and molecules. Cell recovery after hypo-osmotic stress has shown to be consistent with an influx of extracellular Calcium.[9] This influx of calcium may alter the cell's permeability.[9]
Additionally, some organisms have been shown to use phenothiazines to regulate and prevent the efflux of amino acids. Changes in the cell's permeability allows the efflux of amino acids during recovery.[9]
Hypo-osmotic stress is correlated with extracellular ATP release. ATP is used to activate purinergic receptors.[10] These receptors regulate sodium and potassium levels on either side of the cell membrane.
^Lang KS, Lang PA, Bauer C, Duranton C, Wieder T, Huber SM, Lang F (2005). "Mechanisms of suicidal erythrocyte death". Cellular Physiology and Biochemistry. 15 (5): 195–202. doi:10.1159/000086406. PMID 15956782.
^Kültz D, Burg M (November 1998). "Evolution of osmotic stress signaling via MAP kinase cascades". The Journal of Experimental Biology. 201 (Pt 22): 3015–21. doi:10.1242/jeb.201.22.3015. PMID 9787121.
^Kültz D (November 2007). "Osmotic stress sensing and signaling in animals". The FEBS Journal. 274 (22): 5781. doi:10.1111/j.1742-4658.2007.06097.x. PMID 17944944.
^Ho SN (January 2006). "Intracellular water homeostasis and the mammalian cellular osmotic stress response". Journal of Cellular Physiology. 206 (1): 9–15. doi:10.1002/jcp.20445. PMID 15965902. S2CID 21178769.
^Brocker C, Thompson DC, Vasiliou V (August 2012). "The role of hyperosmotic stress in inflammation and disease". Biomolecular Concepts. 3 (4): 345–364. doi:10.1515/bmc-2012-0001. PMC3438915. PMID 22977648.
^Erickson, Geoffrey R.; Alexopoulos, Leonidas G.; Guilak, Farshid (2001). "Hyper-osmotic stress induces volume change and calcium transients in chondrocytes by transmembrane, phospholipid, and G-protein pathways". Journal of Biomechanics. 34 (12): 1527–1535. doi:10.1016/S0021-9290(01)00156-7. PMID 11716854.
^ abcPierce, Sidney K.; Politis, Alexander D.; Smith, Laurens H.; Rowland, Laura M. (1988). "A ca2+ Influx in Response to Hypo-Osmotic Stress May Alter Osmolyte Permeability by a Phenothiazine-Sensitive Mechanism". Cell Calcium. 9 (3): 129–140. doi:10.1016/0143-4160(88)90016-4. PMID 3138029.
^Shahidullah, M.; Mandal, A.; Beimgraben, C.; Delamere, N.A. (2012). "Hyposmotic Stress Causes ATP Release and Stimulates Na,K‐ATPase Activity in Porcine Lens". Journal of Cellular Physiology. 227 (4): 1428–1437. doi:10.1002/jcp.22858. PMID 21618533. S2CID 22378117.
November 23, 2023
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Osmotic shock or osmotic stress is physiologic dysfunction caused by a sudden change in the solute concentration around a cell which causes a rapid change in the movement of water across its cell membrane Under hypertonic conditions conditions of high concentrations of either salts substrates or any solute in the supernatant water is drawn out of the cells through osmosis This also inhibits the transport of substrates and cofactors into the cell thus shocking the cell Alternatively under hypotonic conditions when concentrations of solutes are low water enters the cell in large amounts causing it to swell and either burst or undergo apoptosis 1 Tonicity Graphic In isotonic solutions water flows equally into and out of the cell In hypertonic solutions water flows out of the cell and the cell shrinks In hypotonic solutions water flows into the cell and the cell grows All organisms have mechanisms to respond to osmotic shock with sensors and signal transduction networks providing information to the cell about the osmolarity of its surroundings 2 these signals activate responses to deal with extreme conditions 3 Cells that have a cell wall tend to be more resistant to osmotic shock because their cell wall enables them to maintain their shape 4 Although single celled organisms are more vulnerable to osmotic shock since they are directly exposed to their environment cells in large animals such as mammals still suffer these stresses under some conditions 5 Current research also suggests that osmotic stress in cells and tissues may significantly contribute to many human diseases 6 In eukaryotes calcium acts as one of the primary regulators of osmotic stress Intracellular calcium levels rise during hypo osmotic and hyper osmotic stresses Contents 1 Recovery and tolerance mechanisms 1 1 For hyper osmotic stress 1 2 For hypo osmotic stress 2 Osmotic damage in humans 3 See also 4 ReferencesRecovery and tolerance mechanisms editFor hyper osmotic stress edit Calcium plays a large role in the recovery and tolerance for both hyper and hypo osmotic stress situations Under hyper osmotic stress conditions increased levels of intracellular calcium are exhibited This may play a crucial role in the activation of second messenger pathways 7 One example of a calcium activated second messenger molecule is MAP Kinase Hog 1 It is activated under hyper osmotic stress conditions 8 and is responsible for an increase in the production of glycerol within the cell succeeding osmotic stress More specifically it works by sending signals to the nucleus that activate genes responsible for glycerol production and uptake 8 For hypo osmotic stress edit Hypo osmotic stress recovery is largely mediated by the influx and efflux of several ions and molecules Cell recovery after hypo osmotic stress has shown to be consistent with an influx of extracellular Calcium 9 This influx of calcium may alter the cell s permeability 9 Additionally some organisms have been shown to use phenothiazines to regulate and prevent the efflux of amino acids Changes in the cell s permeability allows the efflux of amino acids during recovery 9 Hypo osmotic stress is correlated with extracellular ATP release ATP is used to activate purinergic receptors 10 These receptors regulate sodium and potassium levels on either side of the cell membrane Osmotic damage in humans editMain article Osmotic demyelination syndromeSee also editOsmolyte Myo Inositol Taurine and Taurine transporting ATPase Creatine Betaines Trimethylglycine A Betaine and metabolite of Choline Sorbitol GlycerophosphocholineReferences edit Lang KS Lang PA Bauer C Duranton C Wieder T Huber SM Lang F 2005 Mechanisms of suicidal erythrocyte death Cellular Physiology and Biochemistry 15 5 195 202 doi 10 1159 000086406 PMID 15956782 Kultz D Burg M November 1998 Evolution of osmotic stress signaling via MAP kinase cascades The Journal of Experimental Biology 201 Pt 22 3015 21 doi 10 1242 jeb 201 22 3015 PMID 9787121 Kultz D November 2007 Osmotic stress sensing and signaling in animals The FEBS Journal 274 22 5781 doi 10 1111 j 1742 4658 2007 06097 x PMID 17944944 Unique Characteristics of Prokaryotic Cells Ho SN January 2006 Intracellular water homeostasis and the mammalian cellular osmotic stress response Journal of Cellular Physiology 206 1 9 15 doi 10 1002 jcp 20445 PMID 15965902 S2CID 21178769 Brocker C Thompson DC Vasiliou V August 2012 The role of hyperosmotic stress in inflammation and disease Biomolecular Concepts 3 4 345 364 doi 10 1515 bmc 2012 0001 PMC 3438915 PMID 22977648 Erickson Geoffrey R Alexopoulos Leonidas G Guilak Farshid 2001 Hyper osmotic stress induces volume change and calcium transients in chondrocytes by transmembrane phospholipid and G protein pathways Journal of Biomechanics 34 12 1527 1535 doi 10 1016 S0021 9290 01 00156 7 PMID 11716854 a b Kim Jiyoung Oh Junsang Sung Gi Ho 2016 MAP Kinase Hog1 Regulates Metabolic Changes Induced by Hyperosmotic Stress Frontiers in Microbiology 7 732 doi 10 3389 fmicb 2016 00732 PMC 4870262 PMID 27242748 a b c Pierce Sidney K Politis Alexander D Smith Laurens H Rowland Laura M 1988 A ca2 Influx in Response to Hypo Osmotic Stress May Alter Osmolyte Permeability by a Phenothiazine Sensitive Mechanism Cell Calcium 9 3 129 140 doi 10 1016 0143 4160 88 90016 4 PMID 3138029 Shahidullah M Mandal A Beimgraben C Delamere N A 2012 Hyposmotic Stress Causes ATP Release and Stimulates Na K ATPase Activity in Porcine Lens Journal of Cellular Physiology 227 4 1428 1437 doi 10 1002 jcp 22858 PMID 21618533 S2CID 22378117 Retrieved from https en wikipedia org w index php title Osmotic shock amp oldid 1177400749, wikipedia, wiki, book, books, library,
