Glutamine and glucose metabolism in intraepithelial lymphocytes from pre- and post-weaning pigs.
The metabolism of glutamine (Gln) and glucose was studied in intraepithelial lymphocytes (IEL) from 21-, 29- and 56-day-old pigs. Pigs were weaned at 21 days of age. Cells were incubated at 37 degrees C in the presence of Krebs-Ringer bicarbonate buffer (pH 7.4) containing 1 mM [U-14C]glutamine plus 5 mM glucose, or 5 mM [U-14C]glucose plus 1 mM glutamine. Glucose was converted to lactate, pyruvate and CO2, which accounted for 81, 11 and 8% of measured glucose carbon, respectively. Glutamine was metabolized mainly to glutamate (92% of Gln C) and ammonia, and to a lesser extent, to aspartate (4% of Gln C) and CO2 (4% of Gln C). In the presence of both glucose and glutamine, glucose provided 2-3-fold more ATP to IELs than glutamine in 21-56-day-old pigs, on the basis of their measured end products. The rates of ammonia and glutamate production from glutamine in IELs from 29-day-old pigs were 112 and 90% greater than those in cells from 56-day-old pigs, respectively. The rates of glucose oxidation to CO2 in IELs from 29-day-old pigs were elevated 56 and 64% respectively, compared with 21- and 56-day-old pigs. Elevated rates of substrate metabolism in IELs from 29-day-old post-weaning pigs indicated a metabolic alteration of these cells possibly due to changes in diet and intestinal bacterial population.
Dugan
M E
ME
Department of Animal Science, Texas A&M University, College Station 77843-2471.
Knabe
D A
DA
Wu
G
G
D000255:Adenosine Triphosphate / Q000032:analysis; D000367:Age Factors; D000818:Animals; D002478:Cells, Cultured; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D005973:Glutamine / Q000378:metabolism*; D008214:Lymphocytes / Q000378:metabolism*; D013552:Swine; D014886:Weaning
D005973:Glutamine; D000255:Adenosine Triphosphate; D005947:Glucose