The blood level of transforming growth factor-beta rises in the early stages of acute protein and energy deficit in the weanling mouse.
Plasma transforming growth factor (TGF)-beta levels are high in the advanced stages of acute (wasting) pre-pubescent deficits of protein and energy. Consequently, this potently anti-inflammatory cytokine may help to sustain the depression of inflammatory immune competence in acute malnutrition. Our objective was to determine if plasma TGF-beta levels rise during the early stages of acute malnutrition and, secondarily, to confirm the elevation reported previously in advanced weight loss. In two experiments, male and female C57BL/6J mice, initially 19 d old, consumed ad libitum a complete purified diet (group C), or in restricted daily quantities (group R) or had free access to an isoenergetic low-protein diet (group LP). TGF-beta bioactivity in platelet-poor plasma was determined via inhibition of Mv1Lu mink lung cell proliferation after 3 d (Expt 1, early stage) or 14 d (Expt 2, advanced stage) of dietary intervention. At 3 d, mean plasma TGF-beta bioactivities were 802 (C), 2952 (R) and 4678 (LP) pg/ml, and after 14 d mean bioactivities were 1786 (C), 5360 (R) and 5735 (LP) pg/ml. At both time points, the malnourished groups differed from age-matched controls (P </= 0.05). Thus, metabolically distinct weanling systems mimicking paediatric marasmus (group R) and kwashiorkor (group LP) exhibit an early rise in blood TGF-beta concentration, and this cytokine joins corticosterone and IL-10 as a third anti-inflammatory hormone temporally positioned to contribute to the initiation (and maintenance) of malnutrition-associated immune depression. This investigation contributes new insight into the active anti-inflammatory form of immune competence that appears to prevail in acute pre-pubescent malnutrition.
Monk
Jennifer M
JM
Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada N1G 2W1.
Woodward
Bill
B
D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D007121:Immunocompetence; D007249:Inflammation / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011502:Protein-Energy Malnutrition / Q000097:blood* / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000097:blood*; D014886:Weaning; D015431:Weight Loss
D016212:Transforming Growth Factor beta