Calcium sensing receptor activation in THP-1 macrophages triggers NLRP3 inflammasome and human preadipose cell inflammation

Mol Cell Endocrinol. 2020 Feb 5:501:110654. doi: 10.1016/j.mce.2019.110654. Epub 2019 Nov 15.

Abstract

Excess adipose tissue (AT) associates with inflammation and obesity-related diseases. We studied whether calcium-sensing receptor (CaSR)-mediated NLRP3 inflammasome activation in THP-1 macrophages elevates inflammation in LS14 preadipocytes, modeling deleterious AT cell crosstalk. THP-1 macrophages exposed to cinacalcet (CaSR activator, 2 μM, 4 h) showed elevated proinflammatory marker and NLRP3 inflammasome mRNA, pro-IL-1β protein and caspase-1 activity, whereas preincubation with CaSR negative modulators prevented these effects. The key NLRP3 inflammasome component ASC was silenced (siRNA) in THP-1 cells, and inflammasome activation was evaluated (qPCR, Western blot, caspase-1 activity) or they were further cultured to obtain conditioned medium (CoM). Exposure of LS14 preadipocytes to CoM from cinacalcet-treated THP-1 elevated LS14 proinflammatory cytokine expression, which was abrogated by THP-1 inflammasome silencing. Thus, CaSR activation elevates THP-1-induced inflammation in LS14 preadipocytes, via macrophage NLRP3 inflammasome activation. Modulating CaSR activation may prevent deleterious proinflammatory cell crosstalk in AT, a promising approach in obesity-related metabolic disorders.

Keywords: Calcium sensing receptor; Crosstalk; Macrophages; NLRP3 inflammasome; Preadipocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipocytes / metabolism
  • Adipose Tissue / metabolism
  • Caspase 1 / metabolism
  • Cell Line
  • Cytokines / metabolism
  • Humans
  • Inflammasomes / metabolism*
  • Inflammation / metabolism*
  • Interleukin-1beta / metabolism
  • Macrophages / metabolism*
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism*
  • Obesity / metabolism
  • RNA, Messenger / metabolism
  • Receptors, Calcium-Sensing / metabolism*
  • THP-1 Cells / metabolism*

Substances

  • Cytokines
  • Inflammasomes
  • Interleukin-1beta
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • NLRP3 protein, human
  • RNA, Messenger
  • Receptors, Calcium-Sensing
  • Caspase 1