title: Activation of NF-κB drives the enhanced survival of adipose tissue macrophages in an obesogenic environment.
abstract: OBJECTIVE
  Macrophage accumulation in adipose tissue (AT) during obesity contributes to inflammation and insulin resistance. Recruitment of monocytes to obese AT has been the most studied mechanism explaining this accumulation. However, recent evidence suggests that recruitment-independent mechanisms may also regulate pro-inflammatory AT macrophage (ATM) numbers. The role of increased ATM survival during obesity has yet to be explored.
  
  
  RESULTS
  We demonstrate that activation of apoptotic pathways is significantly reduced in ATMs from diet-induced and genetically obese mice. Concurrently, pro-survival Bcl-2 family member protein levels and localization to the mitochondria is elevated in ATMs from obese mice. This increased pro-survival signaling was associated with elevated activation of the transcription factor, NF-κB, and increased expression of its pro-survival target genes. Finally, an obesogenic milieu increased ATM viability only when NF-κB signaling pathways were functional.
  
  
  CONCLUSIONS
  Our data demonstrate that obesity promotes survival of inflammatory ATMs, possibly through an NF-κB-regulated mechanism.
authors.affiliation: Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, United States.
authors.forename: Andrea A
authors.initials: AA
authors.lastname: Hill
authors.affiliation: Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, United States.
authors.forename: Emily K
authors.initials: EK
authors.lastname: Anderson-Baucum
authors.affiliation: Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, United States.
authors.forename: Arion J
authors.initials: AJ
authors.lastname: Kennedy
authors.affiliation: Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, United States.
authors.forename: Corey D
authors.initials: CD
authors.lastname: Webb
authors.affiliation: Department of Cancer Biology, Vanderbilt University School of Medicine, United States.
authors.forename: Fiona E
authors.initials: FE
authors.lastname: Yull
authors.affiliation: Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, United States; Department of Veterans Affairs, Tennessee Valley Healthcare System, United States.
authors.forename: Alyssa H
authors.initials: AH
authors.lastname: Hasty
keywords: Adipose tissue; Apoptosis; Cleaved caspase-3; Macrophage; NF-κB; Survival