Thymine glycol

Thymine glycol (5,6-dihydroxy-5,6-dihydrothymine) is one of the principal DNA lesions that can be induced by oxidation and ionizing radiation.[1]

Thymine glycol
Names
IUPAC name
5,6-Dihydroxy-5-methyldihydro-2,4(1H,3H)-pyrimidinedione
Other names
5,6-Dihydroxy-5,6-dihydrothymine
Identifiers
3D model (JSmol)
ChemSpider
Properties
C5H8N2O4
Molar mass 160.129 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Aging, stroke

The rate at which oxidative reactions generate thymine glycol and thymidine glycol in the DNA of humans is estimated to be about 300 per cell per day.[2] Oxidized DNA bases that are excised by DNA repair processes are excreted in urine. On a body weight basis, mice excrete 18 times more thymine glycol plus thymidine glycol than humans, and monkeys four times more than humans.[2] It was proposed that rate of occurrence of oxidative DNA damages correlates with metabolic rate, and that a higher rate of oxidative damage might cause a higher rate of cellular aging.[2]

Base excision repair is a major DNA repair pathway for removal of oxidative DNA damages. The rate of repair of thymine glycol damage in human fibroblasts was found to decrease with age.[3] Brain samples from humans who died of stroke were found to be deficient in base excision repair of thymine glycol as well as other types of oxidative damages.[4] It was suggested that impaired base excision repair is a risk factor for ischemic brain injury.[4]


gollark: Minecraft absolutely does *not* get more efficient every version.
gollark: "Hmm, people are annoyed at getting up times they do not like. Maybe we should just tell them to wake up and sleep at different times. Or change working hours. No, the best solution is clearly to meddle with the fabric of time itself."
gollark: It's not, though. It's such a *government* solution to a problem which isn't there.
gollark: <@!151391317740486657> GMT bad, has daylight saving time.
gollark: Time zones bad, UTC good.

References
  1. Basu, AK; Loechler, EL; Leadon, SA; Essigmann, JM (1989). "Genetic effects of thymine glycol: site-specific mutagenesis and molecular modeling studies". Proc. Natl. Acad. Sci. U.S.A. 86: 7677–81. doi:10.1073/pnas.86.20.7677. PMC 298133. PMID 2682618.
  2. Adelman R, Saul RL, Ames BN (1988). "Oxidative damage to DNA: relation to species metabolic rate and life span". Proc. Natl. Acad. Sci. U.S.A. 85 (8): 2706–8. doi:10.1073/pnas.85.8.2706. PMC 280067. PMID 3128794.
  3. Pons B, Belmont AS, Masson-Genteuil G, Chapuis V, Oddos T, Sauvaigo S (2010). "Age-associated modifications of Base Excision Repair activities in human skin fibroblast extracts". Mech. Ageing Dev. 131 (11–12): 661–5. doi:10.1016/j.mad.2010.09.002. PMID 20854835.
  4. Ghosh S, Canugovi C, Yoon JS, Wilson DM, Croteau DL, Mattson MP, Bohr VA (2015). "Partial loss of the DNA repair scaffolding protein, Xrcc1, results in increased brain damage and reduced recovery from ischemic stroke in mice". Neurobiol. Aging. 36 (7): 2319–30. doi:10.1016/j.neurobiolaging.2015.04.004. PMC 5576895. PMID 25971543.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.