Combined effect of arsenic trioxide and radiation on physical properties of hemoglobin biopolymer

Arsenic trioxide (As2O3) has been recently established as one of the most effective drugs for the treatment of patients with acute promyelocytic leukemia. However, it was widely used in therapeutic of many kinds of cancer by combining it with ionizing radiation. Thus, the purpose of the present study was to explain the combined effect of As2O3 and gamma irradiation on hemoglobin (Hb) structure. Measurements using fourier transform infrared (FTIR) and UV-visible spectra were done. This study included five groups: control, irradiation with single dose of gamma irradiation of 5 Gy, intraperitonial injection with single dose of 10 mg/kg body weight of As2O3, As2O3+5 Gy and 5 Gy+As2O3. The results reported that the absorbance of secondary amide, amide I and amide II of all groups were lowerd than control, whereas the absorbance of amide III and amide IV for As2O3 and 5 Gy followed by As2O3 injection has been increased. For UV-visible spectra, As2O3 injection decreased the absorbance of globin-heme and soret bands and increased β, α and 630 bands compared with control. On injection with As2O3 followed by 5 Gy showed a decrease in globin-heme, soret, β and α bands and increase in 630 band. Moreover, 5 Gy followed by As2O3 demonestrated a decrease in globin-heme, β, α and 630 bands and an increase in soret band, also the ratio of α/β showed an increase in absorbance compared with control. The results concluded that 5 Gy followed by As2O3 showed some sort of repair in the structure of rats hemoglobin rather than injection with As2O3 and 5 Gy both individually.