Invited Review: Cytokine Mediators of Malnutrition: Clinical Implications

Abstract

During the past decade, the relationships that exist between inflammatory cytokines and the metabolic changes associated with critical illness have been the focus of extensive research efforts. Alterations in protein metabolism, characterized by increased peripheral protein catabolism and increased hepatic synthesis of acute-phase proteins, have been reported with tumor necrosis factor, interleukin-1, and interleukin-6 administration in animals and humans. Hyperlipoproteinemia has also been observed, particularly in association with increases in very-low-density lipoproteins and hepatic fatty acid synthesis. The release of counter-regulatory hormones in response to cytokine activity contributes to these metabolic changes as well. An understanding of the complex interactions of cytokines as mediators of intermediary metabolism is important to clinicians caring for critically ill patients.