Exploring Natural Products as Radioprotective Agents for Cancer Therapy: Mechanisms, Challenges, and Opportunities

Abstract

Radiotherapy is an important cancer treatment. However, in addition to killing tumor cells, radiotherapy causes damage to the surrounding cells and is toxic to normal tissues. Therefore, an effective radioprotective agent that prevents the deleterious effects of ionizing radiation is required. Numerous synthetic substances have been shown to have clear radioprotective effects. However, most of these have not been translated for use in clinical applications due to their high toxicity and side effects. Many medicinal plants have been shown to exhibit various biological activities, including antioxidant, anti-inflammatory, and anticancer activities. In recent years, new agents obtained from natural products have been investigated by radioprotection researchers, due to their abundance of sources, high efficiency, and low toxicity. In this review, we summarize the mechanisms underlying the radioprotective effects of natural products, including ROS scavenging, promotion of DNA damage repair, anti-inflammatory effects, and the inhibition of cell death signaling pathways. In addition, we systematically review natural products with radioprotective properties, including polyphenols, polysaccharides, alkaloids, and saponins. Specifically, we discuss the polyphenols apigenin, genistein, epigallocatechin gallate, quercetin, resveratrol, and curcumin; the polysaccharides astragalus, schisandra, and Hohenbuehelia serotina; the saponins ginsenosides and acanthopanax senticosus; and the alkaloids matrine, ligustrazine, and β-carboline. However, further optimization through structural modification, improved extraction and purification methods, and clinical trials are needed before clinical translation. With a deeper understanding of the radioprotective mechanisms involved and the development of high-throughput screening methods, natural products could become promising novel radioprotective agents.

Activation of the Immune System against the Background of Its Imbalance Caused by Agents of Radiation Nature

“…The increase in the survival rate of lethally irradiated animals against the background of the use of the drug «Polyapisogen» was due to inhibition of the formation in the irradiated organism of radio-induced products of oxidative modification of macromolecules (OMM) with simultaneous stimulation (or preservation of the activity of the antiradical enzyme, superoxide dismutase (SOD), which is confirmed by the data of other researchers (Martinello M., Mutinelli F., 2021; Fischer N., Seo E.J., 2018). Antiradical activity of the drug «Polyapisogen» is due to the presence of preparation of natural bioantioxidants: phenols, tocopherols, carotenoid, vitamins C and E, which, acting synergistically, inhibit the formation of free radicals, inhibit them, destroy peroxides (dismutation), bind catalysts -metal ions of variable valence, by quenching (quenching) inactivate singlet oxygen (Fischer, Seo, 2018;Adnan, Rasul et al, 2022;Zhang et al, 2023).…”