Identification of Adiponectin Receptor Agonist Utilizing a Fluorescence Polarization Based High Throughput Assay

Abstract

Adiponectin, the adipose-derived hormone, plays an important role in the suppression of metabolic disorders that can result in type 2 diabetes, obesity, and atherosclerosis. It has been shown that up-regulation of adiponectin or adiponectin receptor has a number of therapeutic benefits. Given that it is hard to convert the full size adiponectin protein into a viable drug, adiponectin receptor agonists could be designed or identified using high-throughput screening. Here, we report on the development of a two-step screening process to identify adiponectin agonists. First step, we developed a high throughput screening assay based on fluorescence polarization to identify adiponectin ligands. The fluorescence polarization assay reported here could be adapted to screening against larger small molecular compound libraries. A natural product library containing 10,000 compounds was screened and 9 hits were selected for validation. These compounds have been taken for the second-step in vitro tests to confirm their agonistic activity. The most active adiponectin receptor 1 agonists are matairesinol, arctiin, (-)-arctigenin and gramine. The most active adiponectin receptor 2 agonists are parthenolide, taxifoliol, deoxyschizandrin, and syringin. These compounds may be useful drug candidates for hypoadiponectin related diseases.

Evolving role of adiponectin in cancer-controversies and update

“…It was found to have similar effects to APN in muscle and liver, with downstream effects on AMPK and PPAR-α signalling 168 .…”

“…After screening several molecules 168 , AdipoRon was seen to bind to AdipoR1/R2 at low micromolar concentrations. It was found to have similar effects to APN in muscle and liver, with downstream effects on AMPK and PPAR-α signalling 168 .…”

Orally Active Osteoanabolic Agent GTDF Binds to Adiponectin Receptors, With a Preference for AdipoR1, Induces Adiponectin-Associated Signaling, and Improves Metabolic Health in a Rodent Model of Diabetes

“…Functionally, AdipoRon showed comparable affinity to both AdipoR1 and -2 and acted through both these receptors to bring about physiological improvements in diabetic mice, whereas GTDF showed a stronger affinity for AdipoR1, and given its modest effects on hepatic gluconeogenesis, appears to act mainly via AdipoR1. Incidentally, another recent report identified DHQ (also known as taxifoliol) as one of nine small-molecule AdipoR agonists from a library of 10,000 compounds by a fluorescent polarization-based screen; however, the in vivo efficacy of DHQ is yet to be elucidated (47). DHQ is an enantiomer of the aglycone form of GTDF and was active in our PPARa ligand activation as well, albeit at a 10-fold higher concentration than GTDF.…”

“…DHQ is an enantiomer of the aglycone form of GTDF and was active in our PPARa ligand activation as well, albeit at a 10-fold higher concentration than GTDF. In contrast to GTDF, DHQ displays a stronger affinity for AdipoR2 (47), and thus studies with DHQ alone or in combination with GTDF will be needed to further explore their therapeutic potential in metabolic diseases.…”

Modulation of adiponectin as a potential therapeutic strategy

“…Several small molecules that activate AdipoR1 and AdipoR2 were screened using a high throughput assay [85]. AdipoRon, a recently discovered AdipoR agonist, was found to activate AMPK and PPAR-a pathways in muscle and liver like adiponectin, resulting in improvement of insulin resistance and glucose intolerance in mice on a high-fat diet [86].…”