TY - JOUR
T1 - Accelerated phosphatidylcholine turnover in macrophages promotes adipose tissue inflammation in obesity
AU - Petkevicius, Kasparas
AU - Virtue, Sam
AU - Bidault, Guillaume
AU - Jenkins, Benjamin
AU - Çubuk, Cankut
AU - Morgantini, Cecilia
AU - Aouadi, Myriam
AU - Dopazo, Joaquin
AU - Serlie, Mireille J.
AU - Koulman, Albert
AU - Vidal-Puig, Antonio
N1 - © 2019, Petkevicius et al.
PY - 2019/8/16
Y1 - 2019/8/16
N2 - White adipose tissue (WAT) inflammation contributes to the development of insulin resistance in obesity. While the role of adipose tissue macrophage (ATM) pro-inflammatory signalling in the development of insulin resistance has been established, it is less clear how WAT inflammation is initiated. Here, we show that ATMs isolated from obese mice and humans exhibit markers of increased rate of de novo phosphatidylcholine (PC) biosynthesis. Macrophage-specific knockout of phosphocholine cytidylyltransferase A (CCTα), the rate-limiting enzyme of de novo PC biosynthesis pathway, alleviated obesity-induced WAT inflammation and insulin resistance. Mechanistically, CCTα-deficient macrophages showed reduced ER stress and inflammation in response to palmitate. Surprisingly, this was not due to lower exogenous palmitate incorporation into cellular PCs. Instead, CCTα-null macrophages had lower membrane PC turnover, leading to elevated membrane polyunsaturated fatty acid levels that negated the pro-inflammatory effects of palmitate. Our results reveal a causal link between obesity-associated increase in de novo PC synthesis, accelerated PC turnover and pro-inflammatory activation of ATMs.
AB - White adipose tissue (WAT) inflammation contributes to the development of insulin resistance in obesity. While the role of adipose tissue macrophage (ATM) pro-inflammatory signalling in the development of insulin resistance has been established, it is less clear how WAT inflammation is initiated. Here, we show that ATMs isolated from obese mice and humans exhibit markers of increased rate of de novo phosphatidylcholine (PC) biosynthesis. Macrophage-specific knockout of phosphocholine cytidylyltransferase A (CCTα), the rate-limiting enzyme of de novo PC biosynthesis pathway, alleviated obesity-induced WAT inflammation and insulin resistance. Mechanistically, CCTα-deficient macrophages showed reduced ER stress and inflammation in response to palmitate. Surprisingly, this was not due to lower exogenous palmitate incorporation into cellular PCs. Instead, CCTα-null macrophages had lower membrane PC turnover, leading to elevated membrane polyunsaturated fatty acid levels that negated the pro-inflammatory effects of palmitate. Our results reveal a causal link between obesity-associated increase in de novo PC synthesis, accelerated PC turnover and pro-inflammatory activation of ATMs.
UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85072508480&origin=inward
UR - https://www.ncbi.nlm.nih.gov/pubmed/31418690
U2 - https://doi.org/10.7554/eLife.47990
DO - https://doi.org/10.7554/eLife.47990
M3 - Article
C2 - 31418690
SN - 2050-084X
VL - 8
JO - eLife
JF - eLife
M1 - e47990
ER -