Premium
Insulin‐Like Growth Factor‐I Enhances Immune Response in Dexamethasone‐Treated or Surgically Stressed Rats Maintained With Total Parenteral Nutrition
Author(s) -
Hinton Pamela S.,
Peterson Catherine A.,
Lo HuiChen,
Mccarthy Donna,
Ney Denise M.
Publication year - 1995
Publication title -
journal of parenteral and enteral nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.935
H-Index - 98
eISSN - 1941-2444
pISSN - 0148-6071
DOI - 10.1177/0148607195019006444
Subject(s) - immune system , medicine , endocrinology , dexamethasone , tumor necrosis factor alpha , spleen , insulin like growth factor , concanavalin a , lymphocyte , glucocorticoid , growth factor , biology , immunology , in vitro , receptor , biochemistry
Background: New evidence suggests that insulin‐like growth factor‐I (IGF‐I) is an important regulator of immune response. Our objective was to determine the effects of IGF‐I on immune response during total parenteral nutrition (TPN) using two stress models. Methods: Male, Sprague‐Dawley rats (230 to 250 g) were given TPN with or without coinfusion of recombinant human IGF‐I (800 μg/d for 6 days) and subjected to either dexamethasone, a synthetic glucocorticoid, or surgical stress, in the form of a midline abdominal incision. In the dexamethasone model, immune response was assessed by total cellularity of the thymus and spleen, in vitro assays of lymphocyte proliferation, and interleukin 6 (IL‐6) production, and concentrations of IL‐6 and tumor necrosis factor α (TNF‐α) in serum. In the surgical model, flow cytometry was used to identify and quantify splenic populations of T and B lymphocytes and macrophages. Results: In rats immunosuppressed by dexamethasone, IGF‐I infusion increased mitogen‐induced proliferation of thymocytes, but did not alter cellularity in the thymus; enhanced proliferation and IL‐6 production in peripheral blood mononuclear cells following treatment with concanavalin A or lipopolysaccharide; and reduced the serum concentration of IL‐6, but not TNF‐α. In surgically stressed rats, IGF‐I infusion restored the splenic populations of immature and mature B lymphocytes, which were decreased by TPN. Conclusions: Our data demonstrate that IGF‐I enhances immune response during TPN in rats. (Journal of Parenteral and Enteral Nutrition 19:444–452, 1995)