Photostatins are inhibitors that can be switched on and off in vivo by visible light, to optically control microtubule dynamics.[1][2] Photostatins are a form of photopharmacology. [3]
As a cell prepares to divide, its microtubules, arrange themselves into a spindle that permits its chromosomes to split into two bundles. These bundles become the nuclei of the daughter cells, Out-of-control cell replication is the underlying cause of cancer, developing drugs that interfere with microtubule activity offers one potential therapeutic approach.[2] They can operate microtubule dynamics with a subsecond response time and control mitosis in living organisms with single-cell spatial precision.[1]
Most microtubule inhibitors affect both cancerous and healthy cells, requiring lower doses to avoid severe side effects. Because photostatins are inactive in the absence of light, they only affect cells that are illuminated. Focusing light on tumors directs their activities to appropriate targets with fewer side effects.[2]
One phostatin is combretastatin A-4, one of several combretastatins found in the bark of the South African bushwillow. It comes in two isomers, that share a single composition, but different shapes. One isomer is a poor disrupter of tubule activity while the other is effective.[2][4]
Replacing two adjacent carbon atoms in the molecule with nitrogen atoms changes the non-toxic isomer, which does little to disrupt tubules, into the toxic one in the presence of blue light. This transformation is reversed simply by switching the light off. The drug proved 200 times more toxic when exposed to light in this way than in the dark. The effect increased to 250 times under violet light and decreased to 75 times when exposed to cyan.[2]
^ abBorowiak, Malgorzata; Nahaboo, Wallis; Reynders, Martin; Nekolla, Katharina; Jalinot, Pierre; Hasserodt, Jens; Rehberg, Markus; Delattre, Marie; Zahler, Stefan (2015-07-16). "Photoswitchable Inhibitors of Microtubule Dynamics Optically Control Mitosis and Cell Death". Cell. 162 (2): 403–411. doi:10.1016/j.cell.2015.06.049. ISSN 0092-8674. PMID 26165941.
^ abcde"Colourful chemotherapy". The Economist. July 11, 2015. ISSN 0013-0613. Retrieved 2016-05-01.
^Velema, Willem A.; Szymanski, Wiktor; Feringa, Ben L. (12 February 2014). "Photopharmacology: Beyond Proof of Principle" (PDF). J. Am. Chem. Soc. 136 (6): 2178–2191. doi:10.1021/ja413063e. hdl:11370/d6714f52-c2c8-4e48-b345-238e98bcc776. PMID 24456115.
^Wrighton, Katharine H. (2015). "Cytoskeleton: Controlling microtubules with light". Nature Reviews Molecular Cell Biology. 16 (8): 454. doi:10.1038/nrm4036. S2CID 9719965.
External linksedit
"Photostatin Added to Human Cancer Cell Line". EurekAlert!. Retrieved 2016-05-01.
December 07, 2023
photostatin, inhibitors, that, switched, vivo, visible, light, optically, control, microtubule, dynamics, form, photopharmacology, cell, prepares, divide, microtubules, arrange, themselves, into, spindle, that, permits, chromosomes, split, into, bundles, these. Photostatins are inhibitors that can be switched on and off in vivo by visible light to optically control microtubule dynamics 1 2 Photostatins are a form of photopharmacology 3 As a cell prepares to divide its microtubules arrange themselves into a spindle that permits its chromosomes to split into two bundles These bundles become the nuclei of the daughter cells Out of control cell replication is the underlying cause of cancer developing drugs that interfere with microtubule activity offers one potential therapeutic approach 2 They can operate microtubule dynamics with a subsecond response time and control mitosis in living organisms with single cell spatial precision 1 Most microtubule inhibitors affect both cancerous and healthy cells requiring lower doses to avoid severe side effects Because photostatins are inactive in the absence of light they only affect cells that are illuminated Focusing light on tumors directs their activities to appropriate targets with fewer side effects 2 Contents 1 Combretastatin A 4 2 See also 3 References 4 External linksCombretastatin A 4 editOne phostatin is combretastatin A 4 one of several combretastatins found in the bark of the South African bushwillow It comes in two isomers that share a single composition but different shapes One isomer is a poor disrupter of tubule activity while the other is effective 2 4 Replacing two adjacent carbon atoms in the molecule with nitrogen atoms changes the non toxic isomer which does little to disrupt tubules into the toxic one in the presence of blue light This transformation is reversed simply by switching the light off The drug proved 200 times more toxic when exposed to light in this way than in the dark The effect increased to 250 times under violet light and decreased to 75 times when exposed to cyan 2 See also editPhotopharmacologyReferences edit a b Borowiak Malgorzata Nahaboo Wallis Reynders Martin Nekolla Katharina Jalinot Pierre Hasserodt Jens Rehberg Markus Delattre Marie Zahler Stefan 2015 07 16 Photoswitchable Inhibitors of Microtubule Dynamics Optically Control Mitosis and Cell Death Cell 162 2 403 411 doi 10 1016 j cell 2015 06 049 ISSN 0092 8674 PMID 26165941 a b c d e Colourful chemotherapy The Economist July 11 2015 ISSN 0013 0613 Retrieved 2016 05 01 Velema Willem A Szymanski Wiktor Feringa Ben L 12 February 2014 Photopharmacology Beyond Proof of Principle PDF J Am Chem Soc 136 6 2178 2191 doi 10 1021 ja413063e hdl 11370 d6714f52 c2c8 4e48 b345 238e98bcc776 PMID 24456115 Wrighton Katharine H 2015 Cytoskeleton Controlling microtubules with light Nature Reviews Molecular Cell Biology 16 8 454 doi 10 1038 nrm4036 S2CID 9719965 External links edit Photostatin Added to Human Cancer Cell Line EurekAlert Retrieved 2016 05 01 Retrieved from https en wikipedia org w index php title Photostatin amp oldid 1139486097, wikipedia, wiki, book, books, library,
