Background: Sinapic Acid (SA), as a natural phenolic compound, is widely spread in
Objectives: In this study, the radioprotective effect of SA was investigated against genotoxicity and
apoptosis induced by ionizing radiation in human lymphocytes.
Methods: In this experimental study, peripheral blood samples were collected from human volunteers
and incubated with SA at different concentrations (50-1000 µM) for three hours. The whole
blood samples were exposed to X-ray at the dose of 1.5 Gy. Lymphocytes were cultured with mitogenic
stimulation to determine the micronuclei in cytokinesis-blocked binucleated lymphocyte. The
apoptotic lymphocytes were evaluated by flow cytometry in SA treated and/or irradiated samples.
The antioxidant activities of SA were assayed by two different methods.
Results: SA significantly decreased the frequency of micronuclei and apoptosis in human lymphocytes
exposed to ionizing radiation. The maximum protection and higher decrease in the frequency
of micronuclei in lymphocytes were observed at 1000 µM of SA with 73% of efficacy. SA exhibited
strong free radical scavenging and antioxidant activity at a concentration-dependent antioxidant
Conclusion: This data provides that SA is a powerful radioprotective agent that can protect human
normal cells against the genetic damage and apoptosis induced by ionizing irradiation.