NUTRITIONAL MODULATION OF SOMATOTROPIC AXIS-CYTOKINE RELATIONSHIPS

Authors: Elsasser, Theodore; KAHL, S - UNIVERSITY OF MARYLAND; Steele, Norman; Rumsey, Theron

Submitted to: Comparative Biochemistry and Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/16/1997
Publication Date: N/A
Citation: N/A

Interpretive Summary: Common illnesses in animals as well as people are associated with periods of decreased growth velocity and poor nutrient use. We have reviewed the literature and in conjunction with our own research have suggested that concepts of nutritional management, endocrine system and immune system response need to be integrated to successfully understand and manage the consequences of disease stress. Nutrition has a significant impact on the outcome of illness. Our data suggest that simple changes in protein and energy intake significantly influence the production of hormones from the immune system to signal changes in metabolism that can facilitate the body' response to infection. Similarly selective administration of endocrine hormones like growth hormone may prove beneficial to fighting disease by their ability to stabilize physiologically important processes and bolster the immune system.

Technical Abstract: The objective of this review is to summarize data on the interrelationships that exist between nutrition, the endocrine system and modulation of plasma tumor necrosis factor- responses to endotoxin in cattle. During stress, intake of nutrients often is compromised and a percentage of available nutrients are diverted away from growth processes to stabilize other physiological processes of a higher survival priority. Management practices that minimize the magnitude and duration of disease stress will aid in speeding the return to homeostatic equilibrium. However, the shift away from growth during stress is almost inevitable as a mechanism to survive. Some degree of control and management of the metabolic cost of disease stress involves understanding the integration of nutritional, endocrine and immune signals by cells and working with the natural homeostatic processes. Endocrine and immune system signals, hormones and cytokines, respectively, participate in redirecting nutrient use during disease stress. In an intricate interplay, hormones and cytokines regulate, modify and modulate each other's production and tissue interactions to alter metabolic activities. Levels of dietary protein and energy intake affect patterns of hormones and cytokines in the blood after endotoxin challenge and further modulate the biological actions of many of these regulatory effectors. In vivo, administration of growth hormone to young calves has significant effects to decrease the physiological response to endotoxemia. Many aspects of nutrition can attenuate of facilitate this effect.