The scaffold protein RACK1 is a target of endocrine disrupting chemicals (EDCs) with important implication in immunity

Toxicol Appl Pharmacol. 2017 Jun 15:325:37-47. doi: 10.1016/j.taap.2017.04.011. Epub 2017 Apr 13.

Abstract

We recently demonstrated the existence of a complex hormonal balance between steroid hormones in the control of RACK1 (Receptor for Activated C Kinase 1) expression and immune activation, suggesting that this scaffold protein may also be targeted by endocrine disrupting chemicals (EDCs). As a proof of concept, we investigated the effect of the doping agent nandrolone, an androgen receptor (AR) agonist, and of p,p'DDT (dichlorodiphenyltrichloroethane) and its main metabolite p,p'DDE (dichlorodiphenyldichloroethylene), a weak and strong AR antagonist, respectively, on RACK1 expression and innate immune response. In analogy to endogenous androgens, nandrolone induced a dose-related increase in RACK1 transcriptional activity and protein expression, resulting in increased LPS-induced IL-8 and TNF-α production and proliferation in THP-1 cells. Conversely, p,p'DDT and p,p'DDE significantly decrease RACK1 expression, LPS-induced cytokine production and CD86 expression; with p,p'DDE exerting a stronger repressor effect than p,p'DDT, consistent with its stronger AR antagonistic effect. These results indicate that RACK1 could be a relevant target of EDCs, responding in opposite ways to agonist or antagonist of AR, representing a bridge between the endocrine system and the innate immune system.

Keywords: Anabolic steroids; Cytokines; Endocrine disrupting chemicals; Hormones; Immune system; Pesticides; Signal transduction.

Publication types

  • Comparative Study

MeSH terms

  • Androgen Antagonists / toxicity
  • Androgens / toxicity
  • B7-2 Antigen / metabolism
  • Cell Line
  • Cell Proliferation / drug effects
  • DDT / toxicity
  • Dichlorodiphenyl Dichloroethylene / toxicity
  • Endocrine Disruptors / toxicity*
  • GTP-Binding Proteins / genetics
  • GTP-Binding Proteins / metabolism*
  • Humans
  • Immunity, Innate / drug effects*
  • Interleukin-8 / metabolism
  • Lipopolysaccharides / pharmacology
  • Lymphocyte Activation / drug effects
  • Lymphocytes / drug effects*
  • Lymphocytes / enzymology
  • Lymphocytes / immunology
  • Nandrolone / toxicity
  • Neoplasm Proteins / genetics
  • Neoplasm Proteins / metabolism*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Receptors for Activated C Kinase
  • Receptors, Androgen / drug effects
  • Receptors, Androgen / metabolism
  • Receptors, Cell Surface / genetics
  • Receptors, Cell Surface / metabolism*
  • Receptors, Glucocorticoid / drug effects
  • Receptors, Glucocorticoid / metabolism
  • Signal Transduction / drug effects
  • Transcription, Genetic / drug effects
  • Transfection
  • Tumor Necrosis Factor-alpha / metabolism
  • Up-Regulation

Substances

  • AR protein, human
  • Androgen Antagonists
  • Androgens
  • B7-2 Antigen
  • CD86 protein, human
  • CXCL8 protein, human
  • Endocrine Disruptors
  • Interleukin-8
  • Lipopolysaccharides
  • Neoplasm Proteins
  • RACK1 protein, human
  • RNA, Messenger
  • Receptors for Activated C Kinase
  • Receptors, Androgen
  • Receptors, Cell Surface
  • Receptors, Glucocorticoid
  • Tumor Necrosis Factor-alpha
  • Dichlorodiphenyl Dichloroethylene
  • Nandrolone
  • DDT
  • GTP-Binding Proteins