title: Loss of fat with increased adipose triglyceride lipase-mediated lipolysis in adipose tissue during laying stages in quail.
abstract: The goal of the current study was to investigate regulation of key genes involved in lipid metabolism in adipose and liver to relate lipolytic and lipogenic capacities with physiological changes at the pre-laying, onset of laying, and actively laying stages of quail. Followed by a 50 % increase from pre-laying to onset of laying, adipose to body weight ratio was significantly reduced by 60 % from the onset of laying to the actively laying stage (P < 0.05), mainly resulting from the significantly increased adipocyte size from the pre-laying stage to the onset of laying and reduction of adipocyte size from the onset of laying to the actively laying stage (P < 0.05). In the adipose tissue of actively laying quail, increased protein expression and phosphorylation of adipose triglyceride lipase (ATGL) together with an elevated mRNA expression of comparative gene identification-58, an activator of ATGL, contributes to increased lipolytic activity, as proved by increased amounts of plasma non-esterified fatty acid (P < 0.05). In addition, decreased mRNA expression of fatty acid transport protein in the actively laying quail could contribute to the adipocyte hypotrophy (P < 0.05). In the liver, relative mRNA expression of apo-very low density lipoprotein (VLDL)-II increased significantly from the pre-laying to actively laying stages (P < 0.05), indicating increased apoVLDL-II actively facilitated VLDL secretion in the actively laying quail. These results suggest that the laying birds undergo active lipolysis in the adipocyte, and increase VLDL secretion from the liver in order to secure a lipid supply for yolk maturation.
authors.affiliation: Department of Animal Sciences, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: Shujin
authors.initials: S
authors.lastname: Yang
authors.forename: Yeunsu
authors.initials: Y
authors.lastname: Suh
authors.forename: Young Min
authors.initials: YM
authors.lastname: Choi
authors.forename: Sangsu
authors.initials: S
authors.lastname: Shin
authors.forename: Jae Yong
authors.initials: JY
authors.lastname: Han
authors.forename: Kichoon
authors.initials: K
authors.lastname: Lee
mesh_terms: D000103:Acetyl-CoA Carboxylase / Q000235:genetics / Q000378:metabolism; D017667:Adipocytes / Q000166:cytology / Q000378:metabolism; D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D001053:Apolipoproteins / Q000235:genetics / Q000378:metabolism; D001835:Body Weight; D048429:Cell Size; D005223:Fats / Q000378:metabolism*; D064429:Fatty Acid Synthases / Q000235:genetics / Q000378:metabolism; D050612:Fatty Acid Transport Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D005992:Glycerol-3-Phosphate O-Acyltransferase / Q000235:genetics / Q000378:metabolism; D008049:Lipase / Q000235:genetics / Q000378:metabolism*; D008066:Lipolysis; D008079:Lipoproteins, VLDL / Q000235:genetics / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D011784:Quail / Q000097:blood / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics; D012098:Reproduction
chemical_list: D001053:Apolipoproteins; D005223:Fats; D050612:Fatty Acid Transport Proteins; D008079:Lipoproteins, VLDL; D012333:RNA, Messenger; C027610:apolipoprotein VLDL II; D005992:Glycerol-3-Phosphate O-Acyltransferase; D064429:Fatty Acid Synthases; D008049:Lipase; D000103:Acetyl-CoA Carboxylase