Oligodendrogenesis Via a Small Molecule Therapy for Treating Multiple Sclerosis Patients
Objectives: We investigated how NDC-1308 has gained the function to remyelinate axons, but lost the deleterious side-effects commonly associated with estrogens.
Methods: In silico modeling was used to compare the orientation of NDC-1308 in the estrogen receptor (ER) ligand binding domain to E2. The affinity of NDC-1308 for different ER subtypes was characterized using a fluorescence polarization-based assay. Intracellular pathway activation of NDC-1308 was compared to E2 by real-time qPCR in several human cell lines. We determined whether NDC-1308 is estrogenic, a potential safety concern for treating MS patients. Estrogenicity was directly measured in a mouse uterotrophic assay since E2 treatment is known to cause a rapid and dramatic increase in uterine weight in this assay.
Results: In silico modeling studies suggest that NDC-1308 interacts with different moieties in the ER ligand binding domain compared to E2, thereby eliciting a distinct pattern of gene expression that is beneficial for myelin repair. Indeed, while NDC-1308 and E2 are both ER agonists, the unique remyelinating activity of NDC-1308 can be traced back to its ability to significantly up-regulate key genes (OLIG2, DNER, MOG and MBP) for oligodendrogenesis and remyelination. Real-time qPCR analysis showed these same genes are up-regulated in human PBMCs treated with NDC-1308, suggesting they could serve as potential therapeutic biomarkers. Unlike E2, NDC-1308 was not found to be estrogenic in the uterotrophic assay. Further testing revealed that NDC-1308 is not mutagenic and not genotoxic.
Conclusions: Because of its unique mechanism of action, its potent remyelinating activity and its demonstrated lack of harmful side-effects, NDC-1308 possesses many desirable attributes of an effective MS therapy.