Systemic oxidative stress in Suffolk and Santa Ines sheep experimentally infected with Haemonchus contortus.

The mechanisms responsible for the imbalance between oxidants and antioxidants in sheep infected with Haemonchus contortus are not well established. This study aimed to prove the hypothesis that oxidative stress occurring during infection by H. contortus varies according to breed, and that the parasite burden correlates with hypoalbuminaemia and anaemia. Thus, after deworming and confirming the absence of infection, two different sheep breeds, Suffolk (n = 15) and Santa Ines (n = 22), were orally inoculated with a single dose of 5,000 L3 of H. contortus. The egg counts per gram of faeces (EPG), packed cell volume (PCV) and concentrations of several plasma markers of oxidative stress (lipid peroxidation, albumin, uric acid, total bilirubin, total antioxidant capacity [TAC], total oxidant concentration [TOC] and the oxidative stress index [OSI]) were quantified before (control group) and during the experimental infection (28, 34 and 42 days post-inoculation). In both breeds, TOC increased at 28 days and TAC increased at 42 days. In Suffolk sheep, there was a positive correlation of EPG with oxidant components (28 days) and a negative correlation of EPG with PCV (42 days). In Santa Ines sheep, there was a positive correlation of EPG with bilirubin (r = 0.492; p = 0.020). H. contortus infection caused oxidative stress, which varied according to the breed. Parasite burden was not associated with hypoalbuminaemia, whereas there was a negative correlation with PCV. This research provides the first evidence that the antioxidant status contributes more to the resilience to H. contortus in Santa Ines sheep compared to Suffolk sheep.

Influence of Apical Periodontitis on Stress Oxidative Parameters in Diabetic Rats.

INTRODUCTION: In this study, we investigated if apical periodontitis (AP) associated with diabetes influenced the levels of endogenous antioxidants, the total antioxidant capacity (TAC), and the oxidant parameter in the serum of Wistar rats. METHODS: Forty male rats were divided into 4 equal groups: normal rats (N), rats with AP (AP), diabetic rats (D), and diabetic rats with AP (D + AP). Diabetes was induced by alloxan (150 mg/kg). AP was induced by exposing the pulpal tissue to the oral environment. After 36 days, blood and maxillae were collected. Albumin, bilirubin, uric acid, TAC, and malondialdehyde (MDA) levels were measured, and histologic analysis of the maxillae was performed. P < .05 was set as the threshold for statistical significance. RESULTS: Uric acid levels were higher in the D + AP group when compared with that of the N, D, and AP groups (P < .05). The MDA concentration was higher in the D and D + AP groups when compared with the N and AP groups (P < .05). The level of albumin was lower in the D + AP group when compared with the N, AP, and D groups. Inflammatory infiltration was more intense in the periapical region in the D + AP group compared with that in the AP group (P < .05). CONCLUSIONS: Our findings indicate that diabetes may change the antioxidant status, increase the concentration of MDA and uric acid, and decrease albumin levels in the serum. In addition, AP can potentiate the effects of diabetes by reducing the levels of albumin and increasing the levels of uric acid.