Related Experiment Videos
Hypolipidemic effects of selective liver X receptor alpha agonists
1The Ben May Institute for Cancer Research, Department of Biochemistry and Molecular Biology, the Tang Center for Herbal Medicine Research, 5841 South Maryland Avenue, , Chicago, Illinois 60637, USA.
Abstract:
Recently, a number of nuclear receptors have been identified as key regulators of cholesterol homeostasis. Two of these, liver X receptor alpha (LXRalpha) (NR1H3) [1] and ubiquitous receptor (UR) (NR1H2) [1], appear to be involved in cholesterol reverse transport and disposal. LXRalpha null gene mice fail to adapt metabolically to high-cholesterol diets. We have recently shown that some 6alpha-hydroxylated bile acid analogs are selective activators of LXRalpha. In this report, we show that these orally administered LXRalpha agonists have an overall hypolipidemic effect in hypercholesterolemic rats, mice and hamsters, which indicates that in these animal models, endogenous LXRalpha agonist is a limiting factor for induction of cholesterol disposal. Furthermore, in animals, these 6alpha-hydroxylated bile acid analogs exhibit a unique pharmacokinetic profile and do not increase the serum triglyceride level; therefore, they may represent a novel class of therapeutic agents for cholesterol management.
Insights
Novel bile acid analogs activate liver X receptor alpha (LXRalpha), demonstrating a hypolipidemic effect in animal models. This suggests LXRalpha agonists may offer a new approach to cholesterol management.
Area of Science:
- Biochemistry
- Pharmacology
- Metabolic Diseases
Background:
- Nuclear receptors, including liver X receptor alpha (LXRalpha) and ubiquitous receptor (UR), are crucial for cholesterol homeostasis.
- LXRalpha plays a key role in cholesterol reverse transport and disposal, as evidenced by metabolic inflexibility in LXRalpha null mice on high-cholesterol diets.
Purpose of the Study:
- To investigate the therapeutic potential of 6alpha-hydroxylated bile acid analogs as selective LXRalpha activators.
- To evaluate the hypolipidemic effects and pharmacokinetic profile of these novel compounds in animal models of hypercholesterolemia.
Main Methods:
- Administration of 6alpha-hydroxylated bile acid analogs to hypercholesterolemic rats, mice, and hamsters.
- Assessment of hypolipidemic effects, including changes in cholesterol and triglyceride levels.
- Evaluation of pharmacokinetic profiles of the bile acid analogs.
Main Results:
- Orally administered LXRalpha agonists exhibited a significant hypolipidemic effect across all tested animal models.
- Endogenous LXRalpha agonist appears to be a limiting factor in cholesterol disposal in these models.
- The bile acid analogs demonstrated a unique pharmacokinetic profile and did not elevate serum triglyceride levels.
Conclusions:
- 6alpha-hydroxylated bile acid analogs are effective LXRalpha agonists with hypolipidemic properties.
- These compounds may represent a novel therapeutic class for managing cholesterol levels.
- The findings suggest that LXRalpha activation is a viable strategy for enhancing cholesterol disposal.