Neurotrophins are a family of proteins that induce the survival, development, and function of neurons.
Pleiotrophin (PTN) also known as heparin-binding brain mitogen (HBBM) or heparin-binding growth factor 8 (HBGF-8) or neurite growth-promoting factor 1 (NEGF1) or heparin affinity regulatory peptide (HARP) or heparin binding growth associated molecule (HB-GAM) is a protein that in humans is encoded by the PTN gene. Pleiotrophin is an 18-kDa growth factor that has a high affinity for heparin. It is structurally related to midkine and retinoic acid induced heparin-binding protein.
Tropomyosin receptor kinase A (TrkA), also known as high affinity nerve growth factor receptor, neurotrophic tyrosine kinase receptor type 1, or TRK1-transforming tyrosine kinase protein is a protein that in humans is encoded by the NTRK1 gene.
Tropomyosin receptor kinase B (TrkB), also known as tyrosine receptor kinase B, or BDNF/NT-3 growth factors receptor or neurotrophic tyrosine kinase, receptor, type 2 is a protein that in humans is encoded by the NTRK2 gene. TrkB is a receptor for brain-derived neurotrophic factor (BDNF). Standard pronunciation is "track bee".
Neurotrophin-3 is a protein that in humans is encoded by the NTF3 gene.
Nerve injury is an injury to nervous tissue. There is no single classification system that can describe all the many variations of nerve injuries. In 1941, Seddon introduced a classification of nerve injuries based on three main types of nerve fiber injury and whether there is continuity of the nerve. Usually, however, peripheral nerve injuries are classified in five stages, based on the extent of damage to both the nerve and the surrounding connective tissue, since supporting glial cells may be involved.
Fibroblast growth factor receptor substrate 2 is a protein that in humans is encoded by the FRS2 gene.
RU-58841, also known as PSK-3841 or HMR-3841, is a nonsteroidal antiandrogen (NSAA) which was initially developed in the 1980s by Roussel Uclaf, the French pharmaceutical company from which it received its name. It was formerly under investigation by ProStrakan for potential use as a topical treatment for androgen-dependent conditions including acne, pattern hair loss, and excessive hair growth. The compound is similar in structure to the NSAA RU-58642 but contains a different side-chain. These compounds are similar in chemical structure to nilutamide, which is related to flutamide, bicalutamide, and enzalutamide, all of which are NSAAs similarly. RU-58841 can be synthesized either by building the hydantoin moiety or by aryl coupling to 5,5-dimethylhydantoin.
Cerebrolysin is a mixture of enzymatically treated peptides derived from pig brain whose constituents can include brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF), and ciliary neurotrophic factor (CNTF).
Tavilermide (INN) is a selective, cyclic tripeptide partial agonist of TrkA. Tavilermide was first synthesized by Burgess and co-workers at Texas A&M University with the intention of producing TrkA agonists. It is under development by Mimetogen Pharmaceuticals as an ophthalmic solution for the treatment of dry eyes, and is in phase III clinical trials for this indication. Tavilermide is currently being evaluated in two multi-center phase III clinical studies in the United States for the treatment of dry eye disease. Tavilermide is also in phase I clinical trials for the treatment of glaucoma; studies are ongoing.
SERBA-2, short for selective estrogen receptor beta agonist-2, is a synthetic, nonsteroidal estrogen which acts as a selective ERβ agonist. For the ERα and ERβ, SERBA-2 has affinities (Ki) of 14.5 nM and 1.54 nM, efficacies of 85% and 100%, and EC50 values of 85 nM and 3.61 nM, respectively, demonstrating 9-fold binding selectivity and 11-fold functional selectivity for the ERβ over the ERα. An enantiomer of SERBA-2, erteberel (SERBA-1), is more potent and selective in comparison and is under development for the treatment of schizophrenia.
BNN-20, also known as 17β-spiro-(androst-5-en-17,2'-oxiran)-3β-ol, is a synthetic neurosteroid, "microneurotrophin", and analogue of the endogenous neurosteroid dehydroepiandrosterone (DHEA). It acts as a selective, high-affinity, centrally active agonist of the TrkA, TrkB, and p75NTR, receptors for the neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), as well as for DHEA and DHEA sulfate (DHEA-S). The drug has been suggested as a potential novel treatment for Parkinson's disease and other conditions.
BNN-27, also known as 17α,20R-epoxypregn-5-ene-3β,21-diol, is a synthetic neurosteroid and "microneurotrophin" and analogue of the endogenous neurosteroid dehydroepiandrosterone (DHEA). It acts as a selective, high-affinity, centrally active agonist of the TrkA and p75NTR, receptors for nerve growth factor (NGF) and other neurotrophins, as well as for DHEA and DHEA sulfate (DHEA-S). BNN-27 has neuroprotective and neurogenic effects and has been suggested as a potential novel treatment for neurodegenerative diseases and brain trauma.
Cenegermin, sold under the brand name Oxervate, also known as recombinant human nerve growth factor (rhNGF), is a recombinant form of human nerve growth factor (NGF). In July 2017, it was approved in the European Union as an eye drop formulation for the treatment of moderate or severe neurotrophic keratitis in adults.
Dagrocorat is a nonsteroidal but steroid-like selective glucocorticoid receptor modulator (SGRM) which was under development for the treatment of rheumatoid arthritis but was never marketed. It is described as a partial agonist and "dissociable" agonist of the glucocorticoid receptor. The drug reached phase I clinical trials prior to the discontinuation of its development. The C2α dihydrogen phosphate ester of dagrocorat, fosdagrocorat, was also under investigation, but its development was terminated as well.
EM-5854 is a steroidal antiandrogen which was under development by Endoceutics, Inc. for the treatment of prostate cancer. It was first described in a patent in 2008, and was further characterized in 2012. EM-5854 reached phase I/II clinical trials for the treatment of prostate cancer but development was discontinued in March 2019.
NC 45-0095 is a synthetic nonsteroidal selective estrogen receptor modulator (SERM) which was under development by Novo Nordisk for the treatment of postmenopausal osteoporosis but was never marketed. It is a partial agonist of the estrogen receptor (IC50 (for binding inhibition) = 9.5 nM; EC50 = 13 nM) with mixed estrogenic and antiestrogenic activity, and shows full estrogenic activity in bone and uterus (Emax (relative to moxestrol, in Ishikawa endometrial cancer cell line) = 105%). The compound is a pyrroloindolizine derivative. Its development was discontinued by 2003.
Posovolone is a synthetic neurosteroid which was under development as a sedative/hypnotic medication for the treatment of insomnia. It is orally active and acts as a GABAA receptor positive allosteric modulator. In animals, posovolone shows anticonvulsant, anxiolytic-like, ataxic, and sleep-promoting effects and appeared to produce effects similar to those of pregnanolone. Development of the agent was started by 1999 and appears to have been discontinued by 2007. In 2021, an INN was registered for posovolone with the descriptor of "antidepressant". Posovolone was originally developed by Purdue Pharma.
Neurotrophin mimetics are small molecules or peptide like molecules that can modulate the action of the neurotrophin receptor. One of the main causes of neurodegeneration involves changes in the expression of neurotrophins (NTs) and/or their receptors. Indeed, these imbalances or changes in their activity, lead to neuronal damage resulting in neurological and neurodegenerative conditions. The therapeutic properties of neurotrophins attracted the focus of many researchers during the years, but the poor pharmacokinetic properties, such as reduced bioavailability and low metabolic stability, the hyperalgesia, the inability to penetrate the blood–brain barrier and the short half-lives render the large neurotrophin proteins not suitable to be implemented as drugs.
