Chronic inflammation with oxidative stress emerged as an important pathogenic mechanism in sickle cell disease (SCD) [
1‐
3]. SCD is primarily a disorder of RBCs, which are a significant source of free radicals in biological systems [
4]. Oxidative stress may thus contribute to the abnormalities that underlie the clinical course of SCD [
4]. Oxidative stress is one of the factors that modulate the phenotypic expression of SCD [
5]. Oxygen has the ability to form highly reactive metabolites such as superoxide anion radical (O2
−2), hydrogen peroxide (H
2O
2), and hydroxyl radical (•OH). These reduced metabolites of oxygen are referred to as “reactive oxygen species ROS” [
6]. Oxidative stress can damage specific molecular targets (lipids, proteins, carbohydrates etc.), resulting in cell dysfunction and/or death. Oxidative stress level increases during vaso-occlusive crises and acute chest pain [
7]. Oxidative stress is not only linked to chronic inflammation, it also contributes to endothelial dysfunction [
8].
Sickle cell anemia patients have high levels of oxidative stress markers and low levels of antioxidant capacity. In addition to oxidative stress SCD patients have lower plasma levels of the antioxidant vitamins (A, C and E), lower serum levels of zinc and significantly higher serum levels of copper in comparison to controls [
9,
10]. Zinc deficiency with a copper excess may contribute to free radical production and oxidative damage [
9]. Deficiency of antioxidant vitamins (A, C and E) could account for some of the observed manifestations of SCD such as increased susceptibility to infection and hemolysis [
11]. Any medication that increases the antioxidant capacity is thus expected to favorably influence the clinical course of the disease. Gum Arabic (GA) is an edible, dried, gummy exudate from the stems and branches of Acacia Senegal and Acacia Seyal. Oral intake of GA has been shown to provide several health benefits [
12], such as prebiotic effects [
13]. GA significantly increases Bifidobacteria, Lactobacteria, and Bacteriodes in the gut [
13]. GA is claimed to have anti-cancer [
13], anti-malarial [
14] and immune-modulatory effects [
14,
15]. GA is considered to act as an anti-oxidant and cytoprotective agent [
16] and it can protect against experimental hepatic, renal and cardiac toxicities in rats [
19]. GA is assumed to be effective mainly due to strong anti-oxidant properties [
17,
20,
21]; GA may enhance the activity of superoxide dismutase (SOD) in kidney [
22]. Amino acids tyrosine, histidine and methionine seem to be responsible for the antioxidant capacity of GA against ROS [
23]. In experimental chronic renal failure (CRF) in rats GA administration decreased the superoxide production to control levels and raised the level of GSH and TAC. Alyahia et al. revealed that GA offers protection against cyclophosphamide-induced urinary bladder cytotoxicity in a rat model by neutralizing ROS and mitigating oxidative stress [
16]. GA was effective as a potent superoxide scavenger in doxorubicin induced cardiotoxicity murine model [
24]. Moreover, GA was found to decrease MDA renal level on Cisplatin-Induced nephrotoxicity rat model [
25].
These observations suggest that GA may find clinical application in a variety of conditions where cellular damage is a consequence of oxidative stress like sickle cell anemia. We hypothesized that regular intake of GA would increase the TAC and decrease the oxidative stress markers. The present study tested whether Gum Arabic may have anti-oxidant properties in SCA patients.
To the best of our knowledge this is the first study conducted to investigate the effect of oral administration of GA on anti-oxidant capacity in sickle cell anemia patients.