Increase in Antilipoperoxidant Activity of Plasma as a Consequence of an Inflammatory Reaction Induced by Subcutaneous Turpentine in the Rabbit

Abstract

In the rabbit, an acute inflammatory reaction triggered by the subcutaneous administration of turpentine induces in hepatic tissues an oxidative stress, as well as a decrease in activity of enzymatic scavengers of reactive oxygen species (ROS). The objective of this study was to investigate, the repercussions of a local inflammatory reaction on the antioxidant capacity and markers of systemic oxidative stress in plasma. To this purpose, rabbits received a s.c. injection of turpentine (5 mL/kg) or NaCl 0.9% (w/v). Blood samples were collected at different times during the 48 hours of the experiment to evaluate: firstly, the antilipoperoxidant activity of plasma by measuring the inhibition of autoxidation of brain homogenate, and the concentrations of tocopherol and ascorbic acid; secondly, the severity of oxidative stress in plasma by assaying the concentration of thiobarbituric acid reactive substances (TBARS), and the concentration of ascorbyl radical. The results show that the antilipoperoxidant capacity of plasma gradually increased to be 167% higher than baseline values (p < 0.05) after 48 hours of experiment. α-Tocopherol and ascorbic acid levels increased by 49% and 80%, respectively (p < 0.05) during the first 24 hours. Lipid peroxidation continuously increased to be 98% higher than baseline values (p < 0.05) at 48 hours, while ascorbyl radical levels were not modified (p < 0.05). In summary, an acute local inflammatory reaction causes a steady progression of oxidative stress, while it stimulates the antilipoperoxidant activity of plasma, to which a-tocopherol and ascorbic acid appear to contribute, essentially early in the inflammation.

Key Words:

• Inflammation
• reactive oxygen species
• antioxidants
• plasma
• lipid peroxidation