Publication

Abstract : Introduction Storage of red cells is associated with some significant biochemical and metabolic changes. Red cells when exposed to oxidative stress during storage as it was reflected by increasing levels of lipid peroxidation, Hb oxidation and osmotic lysis. These deleterious changes were more pronounced after gamma irradiation at 25 Gy. L carnitine, a naturally occurring antioxidant, known for its role in facilitating mitochondrial beta oxidation of long chain fatty acids and membrane repair.  Materials and Methods A total of 30 red cell units were studied. The blood bags were divided in two aliquots. L carnitine was added to one aliquot and other half without L carnitine served as a control. Both the halves were irradiated at 25 Gy and stored for 28 days. Markers of oxidative injury and membrane damage were investigated to assess role of L carnitine as antioxidant.  Results The mean levels of plasma K+ and supernatant Hb and MDA were significantly lower in L carnitine fortified irradiated red cells compared to gamma irradiated red blood cells without carnitine. (mean plasma Hb 0.363 gm/dl vs 0.281 gm/dl, mean K+ 51.24.4 mmol/L v/s 46.33.3* mmol/L and mean MDA 5.010.99 mmol/L v/s 4.04*1.13 mmol/L). L carnitine provided beneficial effect against such radiation induced red cell damage.  Conclusion Lower levels of markers of red cell membrane damage and oxidative injury were observed in L carnitine fortified irradiated red blood cells compared to non-irradiated. Since L carnitine is also a naturally occurring compound, it can be added to the blood bags for protection of red blood cells against oxidative damage. Keywords:- Oxidative Injury, Gamma Irradiation, L Carnitine, Red Cell Storage Lesion. Rajendra Chaudhary Professor & Head, Transfusion Medicine Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India I. INTRODUCTION Red blood cells are exposed to oxidative stress during storage at 4oC which results in damage to membrane and oxidative injury contributing to storage lesions considerably. The red cell membrane damage and oxidative injury makes the erythrocytes more prone to oxidative stress as shown by increase in various markers of oxidative injury such as leakage of hemoglobin and intracellular potassium ions. As the membrane integrity is compromised there is increase in osmotic fragility of red cells and loss of lactate dehydrogenase (LDH), an intracellular enzyme. The enzymes and hemoglobin are released in supernatant plasma. [1] As a measure of prevention of transfusion associated graft versus host disease, the cellular blood components such as red cells and platelets are irradiated before transfusion. Irradiation leads to formation of reactive oxygen species (ROS) e.g. hydroxyl radical. These ROS are free radicals which are potent oxidants. When these oxidants interact with red blood cells and other blood components which are formed by proteins and lipids, they cause oxidation of membrane by lipid peroxidation. [2, 3]. Similarly, gamma irradiation of blood components prevents TA-GVHD but during the process of irradiation there is damage of red cell membrane which reduces their survival [4]. The damage caused to the red cell membrane after irradiation makes it porous as membrane integrity is compromised. This leads to leakage of intra corpuscular components such as intracellular potassium, free Hb and makes the membrane to lose lipid as lipid vesicles [5,6,7]. There is a gradual increase in Thiobarbituric acid reactive substances (TBARS) / malondialdehyde (MDA) levels are observed in red cells which are exposed to irradiation which suggest oxidative process occurs due to irradiation [8,9]. Loss of membrane integrity due to oxidation of membrane lipids and protein results in cell death [10]. Oxidative damage occurring during storage of red blood cells and after irradiation can be prevented either by incorporation of antioxidant in the bags or by supplementing the donor with a course of antioxidants. Various antioxidants have been studied to evaluate the IJISRT19AUG958 www.ijisrt.com 968 Volume 4, Issue 8, August – 2019 International Journal of Innovative Science and Research Technology ISSN No:-2456-2165 protective affect against oxidative injury occurring to red cell during gamma irradiation [11, 12]. L-Carnitine, facilitates mitochondrial beta oxidation of long chain fatty acids which has been used for prevention of storage lesions during red blood cell storage [13]. Red cells have substantial amounts of L-carnitine and its esters and also contain carnitine palmitoyl transferase (CPT), an enzyme. This enzyme helps in transference acyl moiety from coenzyme A to L carnitine [14]. L-Carnitine has shown its role in stability of red cell membrane under different stressful conditions. It has also been reported that L-carnitine may be involved in repair mechanism of red cell membrane phospholipids after oxidative challenge by replacing oxidized fatty with acyl carnitines in membrane phospholipids [15]. In view of the membrane lesions occurring during gamma irradiation of red cells and the potential beneficial effect of L carnitine in preventing the membrane damage, the protective effect of L carnitine in was investigated. The study was aim to assess ability of L carnitine in prevention of gamma irradiation induced oxidative and membrane injury in red blood cell components stored over a period of 28 days at 4oC. The markers of membrane damage such as malondialdehyde (MDA), hemoglobin oxidation and osmotic fragility and markers of oxidative injury were studied.