Naslov
Scientific base for using propolis and its polyphenolic/flavonoid compounds as an adjunct to radiation therapy

Autori
Oršolić, Nada ; Benković, Vesna ; Horvat Knežević, Anica ; Bašić, Ivan

Vrsta, podvrsta i kategorija rada
Poglavlja u knjigama, znanstveni

Knjiga
Scientific evidence of the use of propolis in ehtnomedicine

Urednik/ci
Oršolić, Nada ; Bašić, Ivan

Izdavač
Transworld Research Network

Grad
Lahti

Godina
2008

Raspon stranica
251-310

ISBN
978-81-7895-357-1

Ključne riječi
propolis, flavonoids, radioprotection, immunomodulation, antioxidant activity, genotoxicity

Sažetak
Dietary factors play an important role in human health and in the development of certain chronic diseases including cancer. Polyphenolic compounds are widely distributed in the plant kingdom and display a variety of biological activities, including the free radical scavenging ability, tissue regeneration properties, immunostimulatory effects, chemoprevention and growth inhibition of tumors. It has been well established that biological effects of radiation result from energy deposition in irradiated cells in which reactive oxygen species (ROS), including superoxide anion (O2• ─ ), hydroxyl radical (OH• ) and hydrogen peroxide (H2O2) are produced. However, if overproduction of ROS occurs, oxidative damage can lead to radiation-induced cytotoxicity (chromosomal damage and mutations) or lethality. It is also widely believed that oxidative damage contributes significantly to the development of age-related chronic illness such as cancer and degenerative disease. For these reasons, the search for new radioprotectors that are less toxic than the currently available compounds is crucially needed to develop better strategies for protecting exposed populations from radiation injury. The potential use of flavonoid compounds as a radioprotector is of increasing interest. This review focuses on the radioprotective efficacy of naturally occurring antioxidants, specifically antioxidant nutrients and phytochemicals, and their influence on various endpoints of radiation damage. Results from animal experiments indicate that plant products, such as propolis and related flavonoid compounds, protect against lethality and other types of radiation effects though to a lesser degree than most synthetic protectors ; however antioxidant nutrients and phytochemicals have the advantage of low toxicity as compared to synthetic protectors and they are generally protective when administered at pharmacological doses. Naturally occurring antioxidants may also provide an extended window of protection against low-dose, low-dose-rate irradiation, including their therapeutic potential when administered after irradiation. A number of phytochemicals, including caffeic acid, quercetin, naringin, chrysin and propolis alone, have multiple physiological effects, as well as antioxidant activity, which result in radioprotection in vivo and in vitro. Many antioxidant nutrients and phytochemicals have antimutagenic properties, and their modulation of long-term radiation effects, such those used in cancer, needs further examination. In addition, further studies are required to determine the potential value of specific antioxidant nutrients and phytochemicals during radiotherapy for cancer. The mechanism(s) by which the flavonoids are involved in protection against DNA damage is (are) unknown ; however, their ability to act as reactive oxygen species scavenger and metal ion chelators, carcinogen inactivators, modulators of enzyme activity inhibitors of tumor cell growth, inducers of apoptosis, modulators of DNA repair have been proposed. The suggested protective effects of flavonoids, together with their potent antioxidative and free-radical scavenging activities observed in in vitro and in vivo studies have increased the public’ s interest in the use of flavonoids for their potential health benefits.

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Temeljne medicinske znanosti, Kliničke medicinske znanosti

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