l-carnitine as a Potential Additive in Blood Storage Solutions: A Study on Erythrocytes

Abstract

Erythrocytes undergo various changes during storage (storage lesion) that in turn reduces their functioning and survival. Oxidative stress plays a major role in the storage lesion and antioxidants can be used to combat this stress. This study elucidates the effects of l-carnitine (LC) on erythrocytes of stored blood. Blood was obtained from male Wistar rats and stored (4 °C) for 20 days in CPDA-1 (citrate phosphate dextrose adenine) solution. Samples were divided into-(i) controls (ii) LC 10 (l-carnitine at a concentration of 10 mM) (iii) LC 30 (l-carnitine at a concentration of 30 mM) and (iv) LC 60 (l-carnitine at a concentration of 60 mM). Every fifth day, the biomarkers (haemoglobin, hemolysis, antioxidant enzymes, lipid peroxidation and protein oxidation products) were analysed in erythrocytes. Hemoglobin and protein sulfhydryls were insignificant during storage indicative of the maintenance of hemoglobin and sulfhydryls in all groups. Superoxide dismutase and malondialdehyde levels increased initially and decreased towards the end of storage. The levels of catalase and glutathione peroxidase were lower in experimentals than controls during storage. l-carnitine assisted the enzymes by scavenging the reactive oxygen species produced. Hemolysis increased in all groups with storage, elucidating that l-carnitine could not completely protect lipids and proteins from oxidative stress. Hence, this study opens up new avenues of using l-carnitine as a component of storage solutions with combinations of antioxidants in order to maintain efficacy of erythrocytes.

Keywords: Erythrocytes; Lipid peroxidation; Protein oxidation; Storage; l-carnitine.

Fig. 1

Hemoglobin level in erythrocytes of stored blood. Values are expressed as mean ± SE from 5 samples. LC 10—l-carnitine (10 mM); LC 30—l-carnitine (30 mM); LC 60—l-carnitine (60 mM). Changes between groups (across storage) are represented in upper case, while changes within a group (across treatment groups) are represented in lower case. Those not sharing the same letters are significant

Fig. 2

Lipid peroxidation in erythrocytes of stored blood in terms of Malondialdehyde. Values are expressed as Mean ± SE from 5 samples. LC 10—l-carnitine (10 mM); LC 30—l-carnitine (30 mM) LC 60—l-carnitine (60 mM). Changes between groups (across storage) are represented in upper case, while changes within a group (across treatment groups) are represented in lower case. Those not sharing the same letters are significant

Fig. 3

Protein sulfhydryls in erythrocytes of stored blood (Lysate). Values are expressed as mean ± SE from 5 samples. LC 10—l-carnitine (10 mM); LC 30—l-carnitine (30 mM) LC 60—l-carnitine (60 mM). Changes between groups (across storage) are represented in upper case, while changes within a group (across treatment groups) are represented in lower case. Those not sharing the same letters are significant

Fig. 4

Hemolysis in erythrocytes of stored blood. Values are expressed as mean ± SE from 5 samples. LC 10—l-carnitine (10 mM); LC 30—l-carnitine (30 mM) LC 60—l-carnitine (60 mM). Changes between groups (across storage) are represented in upper case, while changes within a group (across treatment groups) are represented in lower case. Those not sharing the same letters are significant