Stimulation of triacylglycerol synthesis in rat adipocytes by plasma very-low-density lipoproteins.
The effect of human plasma lipoproteins on lipogenesis from glucose has been studied in isolated rat adipocytes. The very-low-density lipoproteins increased lipogenesis specifically, whereas low-density lipoproteins and high-density lipoproteins were without effect. Such stimulation could be reproduced with partially delipidated very-low-density lipoproteins. Nod-esterified fatty acids and glycerol were also without effect. Pretreatment of the adipocytes with trypsin did not alter the effect of very-low-density lipoprotein. The presence of Ca2+ was required for the full activation of lipogenesis. The synthesis of acylglycerol fatty acids and of acylglycerol glycerol were equally increased. The effect of very-low-density lipoprotein was not additive to that of insulin. It is suggested that very-low-density lipoprotein may directly stimulate lipogenesis in fat-cells, particularly in states when the lipoproteins are present at high concentration in the circulation.
D000273:Adipose Tissue / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002374:Catalase / Q000494:pharmacology; D005947:Glucose / Q000378:metabolism; D066298:In Vitro Techniques; D007328:Insulin / Q000494:pharmacology; D008075:Lipoproteins, HDL / Q000097:blood / Q000494:pharmacology; D008079:Lipoproteins, VLDL / Q000097:blood / Q000494:pharmacology*; D008297:Male; D051381:Rats; D013268:Stimulation, Chemical; D014280:Triglycerides / Q000096:biosynthesis*; D014357:Trypsin
D007328:Insulin; D008075:Lipoproteins, HDL; D008079:Lipoproteins, VLDL; D014280:Triglycerides; D002374:Catalase; D014357:Trypsin; D005947:Glucose; D002118:Calcium