The aim of this study was to demonstrate the prospects of applications of the novel carbon-based pharmaceuticals, namely - enterosorbents and fullerenes in biomedical gerontology. We present the results of our own studies as well as the analytical review of the literature data that were available up to now. The dietary enterosorbent, SKN non-coated nitrogen-containing carbon, was found to increase the mean value of male Wistar rats' life-span by 43%, that is comparable with the life-span prolongation effects of the calorie-restricted diets (Frolkis et al., 1989). Some antioxidants, like butylated hydroxytoluene (BHT), when regularly administered into the diets, were also found to increase the life-spans of the animals up to 30% (Harman, 1968; Frolkis et al., 1990). The discovery of new carbon allotropes, the fullerenes (Kroto et al., 1985), has furthered the searching of novel carbon-based drugs. Various water-soluble multi-hydroxyl fullerenes (fullerenols), such as C60(OH)n, demonstrating antioxidant properties have been synthesized recently. Furthermore, endohedral metallofullerenes (M@C2n) were synthesized, which are carbon clusters that contain metal atoms (M = La, Sc, Y, etc.) trapped within a fullerene cage. M@C2n hold much promise as the contrast agents for NMR imaging. For example, relaxivity of Gd-fullerenol has turned out to be 20-folds higher than that of Gd-DTPA (Mikawa et al., 2001). While Gd-DTPA accelerates the NMR relaxation of water protons owing to its large dipolar magnetic moment and long electron spin-relaxation time, the 'spin leakage' of the fullerene shell supplies more effective relaxation mechanism through the contact coupling of the electron spin of M@C82 with the solvent nuclear spins (Koltover et al., 2002). Furthermore, M@C2n with the appropriate particle-emitting radionuclides inside, among them, beta-emitting 89Sr, 90Y, 47Sc, 64Cu, 149Pr, 153Sm, 166Ho, and 177Lu can be synthesized, while advances in the molecular biotechnology provide targeting vectors to deliver therapeutic doses of the ionizing radiation with high specificity for treatment of metastasis cancer tumor cells. Thus, M@C2n, due to their unique physical and chemical properties, provide obvious prospects for designing novel paramagnetic probes and therapeutic radiopharmaceuticals with solitary biomedical features.
This research was sponsored by the Russian Foundation for Basic Research, grant 01-03-32945.