Lens crystallin response to whole body irradiation with single and fractionated doses of gamma radiation

Abstract

Purpose: This study was aimed at determining the effect of whole body irradiation with single and fractionated low doses of γ-radiation on the structure of normal rats lens crystallin with the concept of correlating this with the changes in its molecular weight. Materials and methods: Three groups of Wistar albino rats were involved in this study; the first group is the control (n = 10) and the second group (n = 10) treated with a single dose of 4.0 Gy administered in one application from Cesium-137. The third group (n = 60) was treated for 8 weeks with fractionated dose rate of 0.5 Gy/week. Lens crystallin was analysed for protein content measurements and column chromatography. Results: Measurements of total soluble lens protein indicated pronounced decreases after exposure to single and fractionated doses of γ-radiation. The molecular weights and the protein content for the β_H (with high molecular weight), β_L (with low molecular weight) and γ-crystallin fractions revealed generalized alteration for all groups. Conclusion: Single and fractionated doses of γ-radiations induced lens crystallin changes that might lead to development of cataract due to induction of cross-linking and aggregation. β_H-crystallin was the most stable against radiation induced damage, and the molecular weight of γ-crystallin was the most sensitive to gamma radiation.

Keywords::

• Low-dose gamma irradiation
• single dose
• fractionated dose
• lens crystallin
• protein content
• column chromatography