Panel Disdussion

3rd International Congress 3rd International of Nuclear Congress Medicine of Nuclear & 15th Medicine Iranian Annual & 15th Iranian Congress Annual of
Nuclear Congress Medicine of Nuclear Medicine
Shahid Beheshti Shahid Beheshti University University of Medical Sciences of Medical 19-21 Sciences May 201119-21 May 2011
APPROACHES FOR DEVELOPING RADIOPROTECTORS AGAINST
LOW DOSE IRRADIATION
K.P. Mishra (India)
Nehru Gram Bharati University, George Town, Allahabad 211 002 INDIA &
Ex Radiation Biology and Health Sciences Division, Bhabha Atomic Research
Center, Mumbai
Adverse effects of ionizing radiation became known soon after the
discoveries of X ray and radioactivity at the end of 20 th century. With
the increasing advances in radiation technology, growing concerns
were expressed for likely exposure of humans to radiation with
possible harmful effects. Radiation exposures could arise from
planned, unplanned and natural environmental sources. The planned
sources include diagnostic, therapeutic and industrial sources
whereas unplanned exposures comprise of strategic explosions,
reactor accidents, fall outs, dirty bombs and terrorist attacks. It is
fairly well understood that ionizing radiations affect vital biological
molecules through direct action or through indirect deposition of
energy in abundant water generating reactive oxygen species (ROS).
These ROS, in turn, react with critical biomolecules, namely, lipid,
DNA and proteins leading to deleterious oxidative damage. To protect
living organisms against high and low doses of radiation exposure it
requires developing strategies depending upon the nature of radiation
and severity of exposure. Over the years, a large chain of chemically
synthesized compounds, vitamins, amino acids, nucleic acid
derivatives were investigated for their radioprotective potential but
these results were found not translatable into practical applications
either due to poor efficacy or unacceptable associated toxicity. The
available radioprotectors are either inefficient or unsafe for
applications to humans. The effective radioprotector should be nontoxic,
stable, prolonged activity, low cost and easy availability.
Interestingly, past years have witnessed extensive screening of
various plants for their radioprotective properties. Considering
toxicity as the major constraint for the use of synthetic compounds,
numerous plants have been screened for radioprotective efficacy
against the deleterious effects of ionizing radiation. Herbal
compounds rich in antioxidants may be a potential radioprotector.
Compounds with efficient abilities to neutralize ROS produced by
radiation may form potentially useful radioprotectors for practical
applications. Also, compounds or formulations that can stimulate
immunological responses may be another approach to develop
effective radioprotection. This talk will present a highlight of
developing new approaches for developing radioprotectors against
radiation exposures especially low doses of radiation exposures.
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