Transactivation Assays

Nuclear Hormone Receptor transactivation assays.

CXR has developed or offers a range of nuclear hormone receptor transactivation assays to enable the in vitro determination of a compound’s interaction with these xenoreceptors.  Available assays include:

  • PPAR α (human, bovine & rat)
  • PPARγ (human & rat)
  • PPAR δ (human & rat)
  • FXR (human)
  • LXR (human)
  • Estrogen Receptor alpha (agonism and antagonism) – human
  • Estrogen Receptor beta (agonism and antagonism) – human
  • Androgen Receptor (agonism and antagonism) – human
  • CAR 1, 2 and 3 (human)

CXR offers other nuclear hormone receptor assays as a service (e.g. GR, LXR alpha and beta, RXR alpha, beta and gamma…) – if your receptor is not on the list, please contact us.

PPAR α, γ, δ transactivation assays

Peroxisome proliferator-activated receptors (PPAR’s) are nuclear hormone receptors that are involved in the regulation of numerous pathways including energy metabolism and cell differentiation and are attractive therapeutic targets for a number of indications including obesity, diabetes and oncology. On ligand binding, PPARs like other NHRs act as transcriptional activators of several proteins that regulate numerous biochemical pathways, and have an important role in health and disease.

The three PPAR isoforms, α, γ and δ, each have their own tissue-specific distribution, suggesting that different functions can be ascribed to each of the receptor isoforms. Transactivation assays, which are robust and reproducible and based upon a luciferase reporter, have been developed for each of the three human and three rat isoforms.

PPAR Transactivation Assays

  • Identify whether compounds are PPAR agonists
  • All receptor subtypes are available (α,γ, δ)
  • Useful as a predictive indicator of carcinogenicity in test species and man


Effect of Treatment with known PPAR agonists

Hep G2 cells were transiently transfected with the appropriate human or rat PPAR isoforms and then chemically treated: Rosiglitazone (3μM) or WY 14643 (30μM).

Bovine and human PPARα activation profiles using the known agonist ciprofibrate.