Membrane integrity of two human erythrocyte genotypes in the presence of the aqueous solution of sodium metabisulphite and their correlations in vitro

Abstract

Paul Chidoka Chikezie

Objectives: Membrane integrity is a pre-requisite for cellular functionality. The present study sought to investigate the capacity of normal adult hemoglobin (HbAA) and homozygote hemoglobin S (HbSS) erythrocytes to withstand osmotic stress when incubated over time (0 h ≤ t ≤ 8 h) in relatively low concentrations of Na2 S2 O5 << 2.0 g/100 mL in vitro. Materials and Methods: Erythrocyte mean corpuscular fragility (MCF) index and corresponding erythrocyte membrane stability (EMS) were measured using spectrophotometric methods. Furthermore, erythrocyte malondialdehyde (MDA) concentration in the presence of NaS2 O5 was ascertained by standard methods following pre-mixing of 2.104 mM NaS2 O5 with erythrocyte hemolysate (ratio: 1:2; v/v). Results: HbAA erythrocytes MCF indices in the presence of 0.263 mM-2.104 mM Na2 S2 O5 were lower than that of the control HbAA erythrocyte MCF index. The capacity of Na2 S2 O5 to stabilize HbSS erythrocyte membrane was within the range of 2.01-8.44%. Incubation of HbAA and HbSS erythrocytes genotypes in 2.104 mM Na2 S2 O5 for 8 h gave (MDA) = 1.49 ± 0.03 mmol/mL and (MDA) = 4.82 ± 0.03 mmol/mL, respectively. Conclusion: The present study suggest that the capacity of HbAA and HbSS erythrocytes treated with Na2S2O5 to withstand osmotic stress was hinged on the free radical scavenging capability of Na2S2O5, whereas declining %EMS with time was an outcome of background reaction of Na2S2O5 with membrane structural components.