In vitro: |
Antimicrob Agents Chemother. 1986 Jul;30(1):192-5. | Potentiation by levamisole, methisoprinol, and adenine or adenosine of the inhibitory activity of human interferon against encephalomyocarditis virus.[Pubmed: 2428301 ] | METHODS AND RESULTS: The antiviral action of different human interferons against encephalomyocarditis virus in HeLa cell cultures was analyzed. Cell treatment with levamisole (200 micrograms/ml), methisoprinol (1 mg/ml), or adenine or adenosine (33 or 100 micrograms/ml, respectively) potentiated the anti-encephalomyocarditis virus activity of human interferon by 8- to 32-fold. CONCLUSIONS: A higher level of potentiation (256-fold) was achieved either by combined treatments with levamisole plus methisoprinol or by treatment with one of these compounds plus adenine or adenosine. | Anticancer Res. 2006 Jul-Aug;26(4B):3005-10. | Radiation-induced effect of adenine (vitamin B4) on mitomycin C activity. In vitro experiments.[Pubmed: 16886627] | METHODS AND RESULTS: The radiation-induced biological behavior of adenine (vitamin B4) was investigated in vitro under various conditions, implementing breast cancer cells (MCF-7 line) as a model. In aerated media (46% OH and 54% O2*-) at pH=7.4, adenine at low concentration (2 micromol) acted as an efficient radiation-protecting agent. At higher concentration, however, it inhibited cytostatic properties with regard to cancer cells. This double-track activity is based on its chemical structure. Similar features of adenine were also observed in air-free (46% OH, 44% e- aq, 10% H) as well as in media saturated with N2O (90% OH, 10% H), but with different efficiencies. In the presence of mitomycin C (MMC), adenine retained its double-track behavior. CONCLUSIONS: Hence, adenine and MMC compete for the e- aq, but the electronically excited adenine molecules can transfer electrons to MMC, leading to the additional formation of active MMC-. By implementation of formate for the conversion of OH and H into the transient *COO-, which subsequently transfers electron to MMC, a highest efficiency of MMC- was obtained. |
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