Twenty-four hour fasting increases endotoxin lethality in the rat

Area of Science:

• Physiology
• Toxicology
• Nutritional Science

Background:

• Endotoxemia, a condition caused by endotoxin (ET) exposure, can lead to severe physiological distress and mortality.
• Nutritional status is known to influence the body's response to various stressors, but its specific impact on endotoxemia requires further elucidation.

Purpose of the Study:

• To investigate the effect of 24-hour food deprivation on endotoxin lethality in Sprague-Dawley rats.
• To determine the relationship between endotoxin dose, nutritional status, and mortality.
• To explore the role of liver glycogen in the context of endotoxic shock.

Main Methods:

• Rats were subjected to 24-hour food deprivation or fed normally.
• Endotoxin was administered via intravenous infusion or intraperitoneal bolus at varying doses (LD10-LD80).
• Survival rates were monitored for seven days, and liver glycogen content and histopathological liver damage were assessed.

Main Results:

• Food-deprived rats exhibited significantly higher mortality rates (208-240% increase with IV ET, 87-200% with IP ET) compared to fed rats.
• A linear relationship was observed between endotoxin doses (LD10-LD80) and mortality.
• Endotoxin administration increased liver glycogen content in a dose-dependent manner in non-fasted rats, while fasted rats showed depleted glycogen levels.
• Histopathological liver damage and leucopenia were correlated with endotoxin dose and modified by nutritional status.

Conclusions:

• 24-hour food deprivation substantially increases mortality associated with endotoxin exposure in rats.
• Liver glycogen serves as a critical protective substrate resource during endotoxic shock.
• Nutritional status significantly modulates the severity of endotoxin-induced organ damage and lethality.