Frequency of Background and Radiation-Induced Apoptosis in Leukocytes of Individuals with α-Thalassemia Variants, Assessed by the Neutral Comet Assay

Abstract

To study effects of ionizing radiation on apoptosis induction in leukocytes of alpha-thalassemia (alpha-thal) variants compared to normal controls, venous blood samples were obtained from 10 healthy volunteers and 30 alpha-thal patients. Different types alpha-thal were diagnosed by multiplex polymerase chain reaction (PCR). Blood samples were irradiated with three Gy gamma rays, used for comet assay, immediately or 48 h after irradiation. Results show that the frequency of background as well as apoptosis in silent alpha-thal carriers, alpha-thal carriers and controls was similar but there was a significant difference between Hb H patients and other groups in the study. The increased apoptosis in Hb H patients might suggest that accumulation of beta-globin and oxidative stresses are effective in causing apoptosis, and cells from these patients are more vulnerable to damage from radiation-induced toxic substances. Therefore, from alpha-thal patients, those with Hb H disease might be considered as radiosensitive in terms of apoptosis formation.

The comet assay, DNA damage, DNA repair and cytotoxicity: hedgehogs are not always dead

“…The neutral comet assay was employed by Wilkins et al (19) to analyse radiation-induced apoptosis, and this approach was adopted by Omidkhoda et al (20) to look at the effect of superparamagnetic iron oxide on mesenchymal stem cells, and by Tarang et al (21) in a study of radiation-induced apoptosis in leucocytes from α-thalassemia patients. Russo et al (22), investigating the protective effects of a plant extract on human cells, simply regarded comets with a high tail moment (and high percentage tail DNA) as indicating apoptosis.…”

The modulating effect of royal jelly consumption against radiation-induced apoptosis in human peripheral blood leukocytes

“…found that Ap % in irradiated groups immediately after irradiation were almost similar to those obtained from control samples. [ 24 ] Very low and dose-independent Ap 0Rad could be justified by the fact that apoptosis process might be initiated after irradiation, but it still has not been fulfilled to become morphologically detectable. [ 33 ] Hence, after irradiation, whole blood samples were incubated at 37°C in 5% CO 2 for 24 h to measure Ap 24Rad , as well.…”

“…This cytogenetic method has been widely used to measure IR-induced DNA damage and apoptosis in individual cells. [ 8 22 23 24 25 ]…”