AJP - Endocrinology and Metabolism, Vol 272, Issue 6 E957-E966, Copyright © 1997 by American Physiological Society
Lactate production by swine adipocytes: effects of age, nutritional status, glucose concentration, and insulin
B. K. Heckler and G. B. Carey
Department of Animal and Nutritional Sciences, University of New Hampshire, Durham 03824, USA.
To develop an alternative model in which to study the relationship between
adipose tissue lactate production, obesity, and non-insulin-dependent
diabetes mellitus (NIDDM), we investigated lactate production by swine
adipocytes. Subcutaneous adipocytes from fasted 3-wk-old, fasted 7-mo-old,
and fed 7-mo-old Yucatan minIature swine were isolated and incubated with
0.2, 1, 5, 10, or 25 mM glucose +/- 1 mU/ml insulin. Total glucose
metabolism (TGM) was estimated by product summation. Results showed that 1)
TGM was threefold greater in cells from fasted 7-mo- vs. 3-wk-old swine (P
< 0.05), 2) TGM was 2.7-fold greater in cells from fed 7-mo-old vs.
fasted 7-mo-old swine (P < 0.05), 3) insulin failed to stimulate TGM in
adipocytes from swine of either age and either nutritional status, and 4)
lactate and pyruvate accounted for 34 and 30% of TGM, respectively, in
adipocytes from swine of both ages. Similarities in glucose metabolism and
lactate production in adipocytes from swine and obese NIDDM humans make the
swine a potentially valuable model for studying lactate production
associated with obesity and NIDDM.
