Sex Difference in Lactate Production by Adipocytes from Lean Humans ()
Affiliation(s)
Department of Gastroenterology, School of Medical Sciences, University of Campinas (UNICAMP),
Campinas, S?o Paulo, Brazil.
Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, S?o Paulo, Brazil.
Hospices Civils de Lyon, Université de Lyon, Lyon, France.
ABSTRACT
Lactate is an anaerobic
metabolite produced in the absence of an adequate O2 supply.
Although for a long time considered to be a waste product of glycolysis
resulting from hypoxia, lactate is, in fact, an important source of glucose and
also a gluconeogenic precursor, having a role in metabolic and endocrine
signaling. Lactate is produced by adipocytes and muscle cells. Objectives: In this study, we investigated the sex
differences in lactate production by adipocytes isolated from lean human
visceral adipose tissue. Main Methods: The experiments described were done
using adipocytes isolated from adipose
tissue of lean men and women. Adipocytes were isolated following Rodbell
procedure, with modifications, for posterior analysis of glycerol and lactate
production. Results: Morphometric analysis revealed no significant differences
in the size of adipocytes from men and women (diameter: men: 172 ± 24 μm vs. women: 160 ± 16 μm, n = 4 and
10, respectively). Basal glycerol production was significantly higher in
adipocytes from men compared to women (0.34
± 0.06 vs. 0.16 ± 0.01 μmol/106 cells/60
min; mean ± SEM, n = 7 and 4, respectively; p < 0.05), but there was no
significant difference in basal lactate production (men: 0.1 ± 0.01 μmol/10 cells/60 min vs. women: 0.12 ± 0.02 μmol/10 cells/60 min). However,
when stimulated by norepinephrine, adipocytes from women produced more lactate
than adipocytes from men. Female adipocytes also produced as much lactate as
glycerol, whereas male adipocytes produced
three times more glycerol than lactate. The intracellular mechanisms responsible
for this sex difference in lactate production during norepinephrine-stimulated
lipolysis remain to be identified.
Share and Cite:
Crege, D. , Silveira, H. , Chaim, É. , Pareja, J. , Géloen, A. and Grassi-Kassisse, D. (2014) Sex Difference in Lactate Production by Adipocytes from Lean Humans.
Open Journal of Endocrine and Metabolic Diseases,
4, 52-58. doi:
10.4236/ojemd.2014.43006.