DYNAMIC METABOLIC CHANGES OBSERVED IN AN LPS-INDUCED SYSTEMIC INFLAMMATION RAT MODEL USING CONTINUOUS LONG-TERM...

Area of Science:

• Critical care medicine
• Nutritional science
• Physiology

Background:

• Nutritional management is vital for critically ill patients.
• Accurate nutrition estimation during acute sepsis requires metabolic measurement.
• Long-term indirect calorimetry (IDC) data in systemic inflammation is limited.

Purpose of the Study:

• To investigate long-term metabolic changes during acute systemic inflammation using indirect calorimetry (IDC).
• To assess the impact of varying calorie intake on energy expenditure in a rat model of systemic inflammation.

Main Methods:

• Rats were induced with systemic inflammation using LPS and divided into underfeeding, adjusted feeding, and overfeeding groups.
• Indirect calorimetry was performed for up to 144 hours.
• Body composition and tissue weight were measured to correlate with metabolic data.

Main Results:

• LPS-induced rats showed reduced energy consumption and lost diurnal resting energy expenditure variation initially, with recovery over time.
• Overfeeding resulted in higher resting energy expenditure compared to underfeeding and adjusted feeding.
• Muscle atrophy was observed, but fat tissue loss did not occur.

Conclusions:

• Indirect calorimetry effectively identified metabolic alterations during acute systemic inflammation.
• Calorie intake significantly influences energy expenditure patterns in critical illness.
• This study provides the first long-term IDC measurements in an LPS-induced systemic inflammation rat model.