Oxidative stress in blood of camels (Camelus dromedaries) naturally infected with Trypanosoma evansi.

摘要

Oxidant stress is an imbalance between radical-generating and radical-scavenging activity, resulting in oxidation products and tissue damage. The present study aimed to estimate oxidation and antioxidant status in blood of camels naturally infected with Trypanosoma evansi. Blood samples from T. evansi-infected and healthy (control) female camels were used to determine the free radical nitric oxide (NO) generation in serum, malondialdehyde production in serum (sMDA) and erythrocyte (eMDA) as a biomarker of lipid peroxidation, blood methemoglobin formation (MetHb, a biomarker of hemoglobin oxidation), the antioxidants serum ascorbate and albumin levels, erythrocytic glutathione concentration (GSH), superoxide dismutase (SOD) and catalase (CAT) activities. The infected camels were characterized by macrocytic hypochromic anemia. Trypanosomiasis in camels resulted in significant (P<0.001) stimulation of serum NO (78.93%), eMDA (110.04%), sMDA (67.39%) and MetHb (1.5-fold) coupled with significant reduction (P<0.001) of albumin (27.6%), ascorbate (25.38%), GSH (43.36%), SOD (32.47%) and non-significant increase in CAT (7.06%, P=0.322) compared to control values. In infected camels, a significant positive correlation of NO with eMDA (r=0.546, P=0.009) and MetHb (r=0.490, P=0.021) was detected. By contrast, NO was inversely correlated with RBC (r=-0.546, P=0.009), PCV (r=-0.427, P=0.048) and Hb (r=-0.612, P=0.002). On the other hand, eMDA was inversely correlated with RBC (r=-0.596, P=0.003), PCV (r=-0.516, P=0.014) and Hb (r=-0.613, P=0.002). In addition, methemoglobinemia was negatively correlated with RBC (r=-0.560, P=0.007), PCV (r=-0.470, P=0.027) and Hb (r=-0.585, P=0.004). Our results suggest that chronic T. evansi infection in camels is associated with a state of oxidative process.