An atherogenic lipid profile with low serum paraoxonase-1 activity during nematode infection in rats

Eur J Clin Invest 2010; 40 (11): 984–993 Background Inflammation and oxidative stress are associated with cardiovascular diseases and underlying atherosclerosis. The high density lipoprotein (HDL)‐associated paraoxonase‐1 (PON1) enzyme is known to be involved in the protection of serum lipids from such oxidation. Nonetheless, the disturbances of lipid profile during nematode‐infected model have not yet been studied. Therefore, we aimed to explore the effects of Nippostrongylus brasiliensis infection in male Wistar rats, a model of human gastrointestinal nematode infections, on hepatic PON1 synthesis and the levels of lipid parameters. Materials and methods Nippostrongylus brasiliensis‐infected rats fed standard and high‐fat diets. Serum paraoxonase and arylesterase activities were measured on day 0, 2, 4, 7, and 14 post‐infection (PI). Hepatic PONs and pro‐inflammatory cytokines mRNA expression levels were evaluated in a standard diet‐fed groups, and the disturbances in lipid profile as well as the levels of thiobarbituric acid reactive species (TBARS) and oxidized‐LDL (Ox‐LDL) were measured in high‐fat diet‐fed groups. Results We found that N. brasiliensis‐infected rats fed the standard diet show a significant reduction in serum PON1 activity and down‐regulation of hepatic PON1 mRNA expression as well as up‐regulation of hepatic IL‐1β, IL‐β receptor (R), TNF‐α, and TNFR1 mRNA expressions in association with hepatic recruitments of Kupffer cells and neutrohils. In the presence of the high‐fat diet, N. brasiliensis infection increases serum triglycerides, total cholesterol, LDL/VLDL, TBARS and Ox‐LDL as well as decreases serum HDL coinciding with a maximum serum PON1 reduction. Conclusions Nippostrongylus brasiliensis infection can induce atherogenic lipid profile and reduce serum PON1 activity.