Role of haemoglobin in the protection of cultured lymphocytes against diepoxybutane (DEB), assessed by in vitro induced chromosome breakage

Abstract

Diepoxybutane (DEB) is an alkylating agent that can be used to assess chromosome instability in repair-deficient subjects. Previous authors investigated the role of red blood cells (RBC) in determining individual susceptibility to DEB in normal healthy donors, and demonstrated that a polymorphic enzyme in RBC, Glutathione S-transferase T1 (GSTT1), is involved in DEB detoxification. In the present work we studied the influence of individual GSTM1 and GSTT1 genotypes and the presence of RBC on the frequency of DEB-induced chromosome breakage in lymphocyte cultures from normal individuals and, in particular, the influence of isolated components of RBC: RBC membranes, RBC lysate, and haemoglobin. Our results confirm that individual GSTT1 genotypes modulate the level of genetic lesions induced by DEB; however, this effect was not sufficient to explain the highly significant variation in chromosome breakage between whole blood and RBC-depleted cultures. We showed that RBC can protect cultured lymphocytes against chromosome breakage induced by DEB and we demonstrated the particular role of haemoglobin in the protective effect.

Oxidative Stress-Induced DNA Damage and Repair in Human Peripheral Blood Mononuclear Cells: Protective Role of Hemoglobin

“…Our results are in accordance with the studies which found a negative correlation between hemoglobin level and DNA damage [9], and with the studies that showed protection by normal RBC [10] or fetal RBC [21] of lymphocytes against chromosomal breakage induced in lymphocytes by the alkylating agent diepoxybutane. Similar to our findings, Porto et al suggested that this effect is obtained by hemolysed RBC and more specifically by the hemoglobin [10].…”

“…Similar to our findings, Porto et al suggested that this effect is obtained by hemolysed RBC and more specifically by the hemoglobin [10]. They further suggested an additional protective effect of fetal RBC due to increased antioxidative activity by the increased glutathione transferase, catalase and superoxide dismutase activity in fetal RBC [21].…”

“…Porto et al showed that RBC protected cultured lymphocytes against chromosome breakage induced by the alkylating agent diepoxybutane. This effect was attributed to the RBC hemolysate and hemoglobin, while RBC membrane had no effect [10].…”

Normal red blood cells partially decrease diepoxybutane‐induced chromosome breakage in cultured lymphocytes from Fanconi anaemia patients

“…Consequently, cell protective systems against oxidative stress are involved in DEB detoxification, with red blood cells (RBC), or some of its components in particular, playing an important role. In a previous study, we have shown that RBCs can protect cultured lymphocytes against chromosomal breaks induced by DEB (21). In a previous study, we have shown that RBCs can protect cultured lymphocytes against chromosomal breaks induced by DEB (21).…”

Cytogenetics evaluation of the effect of cord blood versus adult red blood cells on chromosomal breakage in Fanconi anemia

“…It was found that the glutathione S-transferase gene GSTT1 (expressed in RBC) was involved in determining sensitivity of lymphocytes to DEB-induced chromosome aberrations (Porto et al, 2003). This may have important clinical implications in recovering the hematological status of FA patients and reducing chromosome instability (Porto et al, 2010).…”