Differential Modification of Oxic and Anoxic Radiation Damage by Chemicals: I. Simulation of the Action of Caffeine by Certain Inorganic Radical Scavengers

Kesavan, P.C.; Sharma, Gaurav; Afzal, S.M.J.

doi:10.2307/3574865

Cited by 22 publications

(8 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For instance, it is evident from table 1 and from the trend analysis (p < 0.01) that caffeine at 80 mg/kg administered 60 min before irradiation exerts maximal radioprotection. The fact that caffeine concentration and the time of administration are critical for optimal radioprotection had been discussed earlier (Kesavan and Afzal 1975, Kesavan and Ahmad 1976, Kesavan et al 1978. The present data are consistent with the view that caffeine affords radioprotection by fast reactions with radiation-induced species such as OH • radicals, hydrated electrons, singlet oxygen etc.…”

Section: Resultssupporting

confidence: 91%

“…Contrary to several reports during the 1960s and 1970s that caffeine potentiates the DNA damage induced by a variety of physical and chemical agents (Kihlman 1977), Kesavan et al (1973) clearly demonstrated in the barley seed system that caffeine protects against the oxic pathway of γ -ray-induced damage, and that it acts as a radiosensitiser only in the absence of oxygen, or the pathway mediated by it. They also hypothesised (Kesavan and Afzal 1975, Kesavan and Ahmad 1976, Kesavan et al 1978 that radioprotection against the oxic pathway of radiobiological damage could possibly be due to a mutually annihilatory reaction of caffeine molecules with the γ -radiation-induced oxygen reactive sites.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Caffeine protects mice against whole-body lethal dose of gamma-irradiation

et al. 1999

View full text Add to dashboard Cite

Administration of caffeine (1,3,7-trimethylxanthine), a major component of coffee, to Swiss mice at doses of 80 or 100 mg/kg body weight 60 min prior to whole-body lethal dose of gamma-irradiation (7.5 Gy) resulted in the survival of 70 and 63% of animals, respectively, at the above doses in contrast to absolutely no survivors (LD-100/25 days) in the group exposed to radiation alone. Pre-treatment with a lower concentration of caffeine (50 mg/kg) did not confer any radioprotection. The protection exerted by caffeine (80 mg/kg), however, was reduced from 70 to 50% if administered 30 min prior to irradiation. The trend statistics reveal that a dose of 80 mg/kg administered 60 min before whole-body exposure to 7.5 Gy is optimal for maximal radioprotection. However, caffeine (80 mg/kg) administered within 3 min after irradiation offered no protection. While there is documentation in the literature that caffeine is an antioxidant and radioprotector against the oxic pathway of radiation damage in a wide range of cells and organisms, this is the first report demonstrating unequivocally its potent radioprotective action in terms of survival of lethally whole-body irradiated mice.

show abstract

Section: Resultssupporting

confidence: 91%

Section: Introductionmentioning

confidence: 99%

Caffeine protects mice against whole-body lethal dose of gamma-irradiation

et al. 1999

View full text Add to dashboard Cite

show abstract

“…These experiments with spores agree with the earlier findings in dried barley seeds (Kesavan, 1973, 1983, 1978 that caf enhances the anoxic pathway of radiation action, but decreases oxic damage at higher [caf]. In barley seeds, the radioprotective action of caf against the oxic pathway might depend on the yield and stability of the radiation-induced, 2 -sensitive sites Afzal 1975, Nadkarni and.…”

Section: Discussionsupporting

confidence: 90%

“…Employing this technique in barley seeds, Kesavan and his co-workers (Kesavan 1973, 1978, Kesavan and Ahmad 1974a, b, Kesavan and Afzal 1975, Kesavan and Dodd 1976, Kesavan and Nadkarni 1977 have demonstrated that caf reported to enhance the radiosensitivity of the seeds via inhibition of biochemical repair mechanisms (Yamamoto andYamaguchi 1969, Ahnstrom 1974) affords protection against oxic damage (equivalent to that component involving long-lived radicals in dried bacterial spores, class III of Powers (1961), or A n of Dodd and Ebert (1970) in Osmunda spores). These studies by Kesavan and co-workers also revealed that only in the absence.of the radiationinduced precursors of oxic damage ( 2 -sensitive sites) does caf dramatically potentiate the anoxic component of radiation damage.…”

Section: Introductionmentioning

confidence: 99%

Differential Modification of Oxic and Anoxic Components of Radiation Damage inBacillus MegateriumSpores by Caffeine

Kesavan¹,

Powers²

1985

International Journal of Radiation Biology and Related Studies

View full text Add to dashboard Cite

Studies were carried out on the effect of caffeine on the X-irradiation sensitivity of B. megaterium spores with the following results: Caffeine exerts a concentration-dependent modifying action on oxygen-dependent components of X-ray-induced damage in B. megaterium spore suspensions causing an 'over-O2 effect' at about 1 X 10(-4) mol dm-3, and as the concentration is increased to 1 X 10(-3) mol dm-3 or above, a small but consistent protection is seen. In the absence of O2, at a wide range of concentrations (8.5 X 10(-5) to 1 X 10(-1) mol dm-3), caffeine enhances the inactivation constant, k, from 1.17 to about 1.50 kGy-1. Both ethanol and t-butanol (5 X 10(-2) mol dm-3) remove the 'over O2-effect' produced by 1.10(-4) mol dm-3 caffeine in O2; such an effect, however, is not accompanied by reduction in the H2O2 concentrations in the spore suspensions. Ethanol prevents caffeine-induced anoxic sensitization, as well as H2O2 buildup. t-BuOH has no influence on either the low dose part of the log fraction survival curve or on the H2O2 yield in the spore suspensions. Caffeine reacts with radiation-induced eaq and .OH with rate constants of 1.5 X 10(10) and 6.9 X 10(9) dm3 mol-1s-1, respectively.

show abstract

“…The deionized water is degassed by boiling for 1 h and then cooling to 4 °C. Then, it is saturated with N 2 gas as described in ref . This technique allows us to decrease drastically the formation of BaCO 3 .…”

Section: Methodsmentioning

confidence: 99%

Local Immiscibility Control on Shape and Size of Nano-objects in the Solvo-Thermal Process: Implications for Ferroelectric Nanoparticles

Bogicevic

Janolin

2020

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

show abstract

Differential Modification of Oxic and Anoxic Radiation Damage by Chemicals: I. Simulation of the Action of Caffeine by Certain Inorganic Radical Scavengers

Cited by 22 publications

References 34 publications

Caffeine protects mice against whole-body lethal dose of gamma-irradiation

Caffeine protects mice against whole-body lethal dose of gamma-irradiation

Differential Modification of Oxic and Anoxic Components of Radiation Damage inBacillus MegateriumSpores by Caffeine

Local Immiscibility Control on Shape and Size of Nano-objects in the Solvo-Thermal Process: Implications for Ferroelectric Nanoparticles

Contact Info

Product

Resources

About