Polyamino- and polyhydroxy-fullerenes show that water-solubility increases with the number of groups introduced into the molecule.
It is possible to state conclusively that water-soluble fullerene derivatives exert considerable protective effects against the oxidative stress as scavengers of free radicals in vitro as well as in vivo (Dugan et al. 2001, Ali et al. 2004, Bakry et al. 2007, Injac et al. 2008).
The radioprotective effects were demonstrated in fullerenols, carboxy-fullerenes, polyvinylpyrrolidone wrapped fullerene, and DF-1.
Table 1 summarizes a comparison of the DRFs after a single water-soluble dendrofullerene DF-1 application 30 min before irradiation (DRF = 1.22) with the effects of other radioprotectants.
Given the fact that these substances (fullerenol, DF-1) have no or only slight side effects, they offer a great potential to become radioprotectants with the possibility of repeated administration, which is necessary in standard fractionated radiotherapy.
The insightful work by Vavrova, Rezacova, and Pejchal presents a promising alternative to the challenges in radiation therapy. Their focus on fullerenes, specifically water-soluble derivatives like C60(OH)24 and dendrofullerene DF-1, illustrates the potential of these carbon nanospheres as viable radioprotectants, demonstrating their potent antioxidative properties and ability to reduce DNA damage in irradiated cells.
Comparatively, the currently used radioprotectant, amifostine, exhibits notable side effects like hypotension, hypocalcaemia, diarrhoea, nausea, and vomiting. Thus, the low-toxic profile of water-soluble fullerenes makes them particularly appealing in radiation therapy.
Nevertheless, it's worth noting that the radioprotective effects of fullerenes are not uniform across the board; the study highlights that polyamino- and polyhydroxy-fullerenes demonstrate increased water-solubility corresponding to the number of groups introduced into the molecule. Furthermore, fullerenol, DF-1, and other similar substances have shown radioprotective effects with minimal side effects.
The task for future research now lies in exploring the mechanisms through which these fullerenes operate as free radical scavengers, both in vitro and in vivo. With such knowledge, we stand at the precipice of potentially transforming the landscape of radiation therapy, ushering in an era of more efficient and safer treatments.