Glucosamine-Induced Endoplasmic Reticulum Stress Promotes ApoB100 Degradation: Evidence for Grp78-Mediated Targeting to Proteasomal Degradation

  title={Glucosamine-Induced Endoplasmic Reticulum Stress Promotes ApoB100 Degradation: Evidence for Grp78-Mediated Targeting to Proteasomal Degradation},
  author={Wei Qiu and Rita Kohen-Avramoglu and Shailen Mhapsekar and Julie Tsai and Richard C. Austin and Khosrow Adeli},
  journal={Arteriosclerosis, Thrombosis, and Vascular Biology},
Objective—To investigate the role of glucosamine-mediated endoplasmic reticulum (ER) stress and Grp78 (BiP) in the intracellular degradation of apolipoprotein B100 (apoB100) in cultured hepatocytes. Methods and Results—Glucosamine treatment (2.5 to 10 mmol/L) of HepG2 cells increased levels of the ER chaperones, 78-kDa glucose-regulated protein (Grp78) and Grp94, in a dose-dependent manner and led to significant decreases in both cellular and secreted apoB100 by up to 97% (P<0.01). In contrast… 

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