Beneficial effects of apolipoprotein A-I on endotoxemia

Purpose. Although many studies have shown the beneficial effects of lipoproteins on animals with endotoxemia, little is known about the impact of apolipoprotein A-I (apoA-I) on tumor necrosis factor alpha (TNF-alpha) release in response to lipopolysaccharide (LPS). The present study was conducted to determine whether the administration of apoA-I inhibits the release of TNF-alpha and influences the survival rate of rats with endotoxemia. Methods. Forty male Wistar rats were divided randomly into four groups. Rats in the first and second groups were given 1 mg/kg LPS intraperitoneally (i.p.) and blood was collected 1 h later to measure the serum levels of TNF-alpha. Either 10 mg/kg apoA-I or Tris-buffered saline was injected i.p. and the serum TNF-alpha levels were measured again 2 h later. Rats in the third and fourth groups were given 5 mg/kg LPS. Following the administration of 10 mg/kg apoA-I or Tris-buffered saline, animals were observed for 5 days and survival rates were determined. Results. ApoA-l inhibited the release of serum TNF-alpha and improved the survival rates of rats with endotoxemia. Conclusion. The administration of apoA-I suppressed the TNF-alpha release in endotoxemia and decreased the mortality rates of rats.