The Medicinal Chemistry and Therapeutic Potential of LRH-1 Modulators

Fragment-Based Discovery of Drug-like LRH-1 Agonists

The phospholipid sensing transcription factor liver receptor homologue 1 (LRH-1) participates in the transcriptional regulation of metabolic balance and inflammation in liver, pancreas, and other tissues. It is an emerging target for metabolic dysfunction, fatty liver disease, and cancer, but LRH-1 modulators are rare and lack drug-like properties. We discovered new LRH-1 ligands with improved physicochemical features in a fragment-based approach and optimized a venlafaxine-related lead for LRH-1 activation. Despite a strict structure-activity relationship, systematic structural variation resulted in a new LRH-1 agonist scaffold with strong activation efficacy, validated direct and cellular target engagement, and anti-inflammatory and ER-stress-resolving properties in functional cellular settings.

Encoded Display of Chemical Libraries on Nanoparticles as a Versatile Selection Tool To Discover Protein Ligands

DNA-encoded library (DEL) technology is a powerful tool for discovering potent ligands for biological targets but constrained by limitations, including the insolubility of DNA in organic solvents and its instability under various reaction conditions, which restrict the reactivity scope and structural diversity achievable in library synthesis. Here, we present a new strategy called nanoDEL, where library molecules and DNA tags are displayed on the surface of nanoparticles. Since nanoparticles disperse well in both organic solvents and aqueous solutions, DEL synthesis can be accomplished using well-established organic solvent-based conditions, eliminating the need for aqueous conditions. Moreover, nanoDEL enables air-sensitive reactions that are inaccessible with conventional DEL methods relying on aqueous conditions. Notably, in nanoDEL, multiple copies of a DNA tag are attached to an individual nanoparticle to encode a single compound, significantly enhancing tolerance to DNA-damaging conditions. Even when most DNA tags are damaged, sequence analysis remains feasible via amplification of intact tags. Consequently, nanoDEL facilitates the convenient use of existing organic reactions without the necessity to develop DNA-compatible reactions. The potential of nanoDEL was validated by affinity selection against streptavidin as a model system and successfully applied to the discovery of potent small-molecule inhibitors for a kinase and stapled peptide inhibitors targeting a protein-protein interaction, exhibiting dissociation constants in the nanomolar range. Furthermore, we demonstrated that a large combinatorial library can be efficiently synthesized on nanoparticles using a synthetic scheme including moisture-sensitive reaction steps, which are not feasible with conventional DELs.

Fatty Acid Mimetic Fragments as Liver Receptor Homologue-1 Modulators

The phospholipid-sensing transcription factor liver receptor homologue-1 (LRH-1) is mainly found in the liver, intestine, and pancreas where it participates in the transcriptional regulation of genes involved in cholesterol and glucose metabolism, inflammation, and endoplasmic reticulum stress. It holds promise as a target in metabolic disease and hepatic/intestinal inflammation treatment, and preliminary evidence suggests potential of LRH-1 modulation for contraception, but LRH-1 modulators are very rare. Based on phospholipid binding to LRH-1, we hypothesized potential for fatty acid mimetics as LRH-1 modulators and discovered new ligand chemotypes by focused fragment screening. Preliminary SAR elucidation, orthogonal activity validation, and target engagement studies highlighted two fragment-like leads for LRH-1 agonist development.

LRH-1 activation alleviates diabetes-induced podocyte injury by promoting GLS2-mediated glutaminolysis

Alteration of metabolic phenotype in podocytes directly contributes to the development of albuminuria and renal injury in conditions of diabetic kidney disease (DKD). This study aimed to identify and evaluate liver receptor homologue-1 (LRH-1) as a possible therapeutic target that alleviates glutamine (Gln) metabolism disorders and mitigates podocyte injury in DKD. Metabolomic and transcriptomic analyses were performed to characterize amino acid metabolism changes in the glomeruli of diabetic mice. Next, Western blotting, immunohistochemistry assays, and immunofluorescence staining were used to detect the expression of different genes in vitro and in vivo. Furthermore, Gln and glutamate (Glu) content as well as ATP generation were examined. A decrease in LRH-1 and glutaminase 2 (GLS2) expression was detected in diabetic podocytes. Conversely, the administration of LRH-1 agonist (DLPC) upregulated the expression of GLS2 and promoted glutaminolysis, with an improvement in mitochondrial dysfunction and less apoptosis in podocytes compared to those in vehicle-treated db/db mice. Our study indicates the essential role of LRH-1 in governing the Gln metabolism of podocytes, targeting LRH-1 could restore podocytes from diabetes-induced disturbed glutaminolysis in mitochondria.

Medicinal Chemistry and Chemical Biology of Nurr1 Modulators: An Emerging Strategy in Neurodegeneration

Nuclear receptor related 1 (Nurr1) is a transcription factor with neuroprotective and antineuroinflammatory properties. Observations from genetic studies and human patients support potential of Nurr1 as a therapeutic target in neurodegeneration, but due to a lack of high-quality chemical tools for pharmacological control of Nurr1, its target validation is pending. Nevertheless, considerable progress has recently been made in elucidating structural and functional characteristics of Nurr1, and several ligand scaffolds have been discovered. Here, we analyze Nurr1's structure and mechanisms compared to other nuclear receptors, summarize the known small molecule Nurr1 ligands, and discuss the available evidence for the therapeutic potential of Nurr1 in neurodegeneration.