Lymphocytes transfer [(14)C]-labeled fatty acids to skeletal muscle in culture; modulation by exercise.
Previous studies have shown that lipids are transferred from lymphocytes (Ly) to different cell types including macrophages, enterocytes, and pancreatic beta cells in co-culture. This study investigated whether [(14)C]-labeled fatty acids (FA) can be transferred from Ly to skeletal muscle (SM), and the effects of exercise on such phenomenon. Ly obtained from exercised (EX) and control (C) male Wistar rats were preloaded with the [(14)C]-labeled free FA palmitic (PA), oleic (OA), linoleic (LA), or arachidonic (AA). Radioactively loaded Ly were then co-cultured with SM from the same Ly donor animals. Substantial amounts of FA were transferred to SM being the profile PA = OA > AA > LA to the C group, and PA > OA > LA > AA to the EX group. These FA were incorporated predominantly as phospholipids (PA = 66.75%; OA = 63.09%; LA = 43.86%; AA = 47.40%) in the C group and (PA = 63.99% OA = 52.72%; LA = 55.99%; AA = 63.40%) in the EX group. Also in this group, the remaining radioactivity from AA, LA, and OA acids was mainly incorporated in structural and energetic lipids. These results support the hypothesis that Ly are able to export lipids to SM in co-culture. Furthermore, exercise modulates the lipid transference profile, and its incorporation on SM. The overall significance of this phenomenon in vivo remains to be elucidated.
Department of Physiology, Federal University of Paraná, Curitiba-PR, Brazil. gapbrito@yahoo.com.br <gapbrito@yahoo.com.br>
Gleisson A P
GA
Brito
Everson A
EA
Nunes
Cláudia
C
Nogata
Ricardo K
RK
Yamazaky
Katya
K
Naliwaiko
Rui
R
Curi
Luiz C
LC
Fernandes
D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism; D002250:Carbon Radioisotopes / Q000737:chemistry; D002478:Cells, Cultured; D018920:Coculture Techniques; D005227:Fatty Acids / Q000378:metabolism*; D019787:Linoleic Acid / Q000378:metabolism; D008214:Lymphocytes / Q000276:immunology / Q000378:metabolism*; D008297:Male; D018482:Muscle, Skeletal / Q000166:cytology / Q000378:metabolism*; D019301:Oleic Acid / Q000378:metabolism; D019308:Palmitic Acid / Q000378:metabolism; D010805:Physical Conditioning, Animal; D051381:Rats; D017208:Rats, Wistar
D002250:Carbon Radioisotopes; D005227:Fatty Acids; D016718:Arachidonic Acid; D019301:Oleic Acid; D019308:Palmitic Acid; D019787:Linoleic Acid