Developing potent and selective BMP inhibitors as translational tools to develop future therapies
Because the heart has negligible intrinsic capacity to regenerate new tissues to replace those lost to injury, there is currently no definitive heart failure treatment, other than organ transplantation. Recent studies have introduced the prospect of replacing damaged heart tissues with healthy cardiomyocytes derived from pluripotent stem cells. However, realizing the full therapeutic potential of more ..
Assay Provider: Charles Hong
Assay Provider Affiliation: Vanderbilt University
Because the heart has negligible intrinsic capacity to regenerate new tissues to replace those lost to injury, there is currently no definitive heart failure treatment, other than organ transplantation. Recent studies have introduced the prospect of replacing damaged heart tissues with healthy cardiomyocytes derived from pluripotent stem cells. However, realizing the full therapeutic potential of stem cells faces numerous hurdles, including the potential for tumor formation, a low rate of cardiomyocyte formation, and an inadequate mechanistic understanding of cardiomyogenesis. Additionally, translational efforts are hampered by a lack of pharmaceutical agents to boost therapeutic effects of stem cells. Dorsomorphin, the first known small molecule inhibitor of the bone morphogenetic protein (BMP) signaling, is one of the most potent chemical inducers of cardiomyogenesis in mouse embryonic stem (ES) cells. Dorsomorphin treatment during the initial 24 to 48 hours of ES cell differentiation was sufficient for robust cardiomyocyte induction. Strikingly, the massive cardiac induction occurs apparently in the absence of mesoderm induction and at the expense of other mesoderm-derived lineages, including endothelial, smooth muscle and hematopoietic lineages. From these results, we hypothesize that a timely BMP signal inhibition commits the primitive multipotent progenitor cells toward the cardiomyocyte development. The aim is to develop potent and selective BMP inhibitors with excellent pharmaceutical properties (no cellular toxicity, high solubility, limited off-target activity) for use in directed differentiation of pluripotent stem cell toward cardiac development and as a pharmaceutical reagent to boost the therapeutic effects of stem cells in myocardial infarction models.
The project plan incorporates HTS assays that serve to identify assay artifacts, cytotoxic compounds, and/or non-selective compounds. In addition, we may elect to perform in silico data mining of the PubChem database to identify compounds with activity in BioAssays employing the same detection format or related targets to identify potential assay artifacts or non-selective compounds. Hits will be prioritized based on their SAR profile determined from HTS, follow-up assays and results of SAR by purchase; the potency, selectivity and chemical tractability of all hit series is considered. Hits or scaffold series that possess potential chemical instability or toxicological problems will be pursued only if clear strategies are devised to address these issues. The chemical series selected for optimization should have the potential to address lesions associated with existing probes, to meet the criteria for a successful probe as laid out in the CPDP, and in all cases to improve the state of the art in the field.
2.2 Profiling AssaysProfiling Assays will be performed on 1 or more candidate compounds meeting the following probe criteria (see Critical Path Flow Chart):1) Highly potent BMP inhibitor in vivo (EC50 <1 M),2) No anti-VEGF activity or nonspecific toxicity in vivo at 50 M,3) No cellular toxicity at 50 M,4) Soluble at 50 - 100 M,5) Highest potency against ALK2 on in vitro kinase assays (target IC50 <50 nM),6) No significant activity against the 7 kinases on the Secondary Assay 4,7) Robust induction of cardiomyogenesis in ES cells.The lead compound will be sent to PanLabs for the Lead Profiling Screen (a panel of 68 G-protein coupled receptors (GPCRs), ion channels, transporters, enzymes screened in triplicate at 10 microM) to confirm that no significant ancillary pharmacology is associated with the compound.
Categorized Comment - additional comments and annotations
From MLP Probe Report:
Probe count: 1
MLP Probe ML# for probe 1: ML347
PubChem Substance ID (SID) for probe 1: 13634969
PubChem Compound ID (CID) for probe 1: 57339378
Probe type for probe 1: Inhibitor
IC50/EC50 (nM) for probe 1: 152; 32
Target for probe 1: BMP4; ALK2 (gi: 18088239)
Disease relevance for probe 1: Basic Research
Anti-target for probe 1: ALK3, ALK4, ALK5, ALK6, BMPR2, TGFBR2
Fold selectivity for probe 1: 337
Grant number for probe 1: HL104040-02
PubMed Publication ID (PMID) for probe 1: 23639540