Recent Patents on CNS Drug Discovery (Discontinued) - Volume 8, Issue 3, 2013

Autoantibodies directed against ion channels and ionotropic receptors are associated with neuromuscular and neurological disorders. Their detection has proven to be useful for diagnosis, prognosis and treatment of these autoimmune syndromes. We have designed an ion channel chip for the systematic and rapid screening of antibodies directed against tens of different ion channels. The chip has been validated by confirming the presence of autoantibodies in patients with anti-NMDA receptor encephalitis. Such a chip will be useful for the diagnosis of already documented disorders, but also to identify new targets of autoimmunity and classification of the corresponding diseases. The article presents some promising patents on the Ion Channel Chip.

The transient receptor potential vanilloid-1 cat ion channel (TRPV1) is a nonspecific cation channel that can be activated by multiple endogenous stimuli and is expressed predominantly in sensory neurons, where it serves as a key nodal point in pain transmission pathways. In mammals, TRPV1 displays a wide tissue and cellular expression including both the peripheral and central nervous system, and in the latter it is now recognized to have a broader distribution and function. The pharmacological modulation of TRPV1 represents a strategy for the treatment of a variety of disease states, particularly those requiring chronic pain management. The validation of the TRPV1 channel as a therapeutic target for the control of pain and inflammatory conditions in a variety of diseases and injury states, has prompted the development of several TRPV1 agonists and antagonists that have entered clinical trials. Studies comparing the analgesic effects of TRPV1 antagonists with and without significant CNS penetration demonstrated that a dual (both peripheral and central) action is required to produce broad-spectrum analgesia. TRPV1 can be considered as a target for next generation analgesics. However, although a number of compounds are in clinical trials, the therapeutic utility of TRPV1 agonist and antagonists is yet to be validated unequivocally. This review summarizes current clinical trials and recent patents with small molecule TRPV1 agonists and antagonists with a focus on neurological conditions.

Currently employed diagnostic ultrasonography provides clinically relevant information about cerebral hemodynamic changes in patients with cerebrovascular ischemia. The information thus obtained is often helpful to the physician for establishing or confirming the diagnosis and prognosis as well as in taking appropriate therapeutic decisions. It is associated with a high temporal resolution and can be performed bedside for rapid diagnosis as well as prolonged monitoring. Transcranial Doppler (TCD) ultrasonography is a non-invasive diagnostic modality that provides physiological information regarding various intracranial hemodynamic alterations in patients with cerebrovascular ischemia. Extended applications of TCD are useful in understanding various pathophysiological mechanisms responsible for the clinical manifestations of cerebrovascular ischemia. Thus, TCD is aptly called as the ‘stethoscope’ of a stroke neurologist. Cerebrovascular ultrasonography is considered as an essential component of a comprehensive stroke center. We have reviewed various recent patents pertaining to the applications of cerebrovascular ultrasonography employed in the selection of stroke patients for various therapeutic interventions.

The blood-brain barrier (BBB) presents a combination of physical and electrostatic barriers. It is a highly complex structure that tightly regulates the movement of molecules from the blood to brain, protecting it from injuries and diseases. However, the BBB also significantly precludes the delivery of drugs to the brain, thus, preventing the therapy of a number of neurological disorders like brain cancer, epilepsy, Alzheimer’s disease, schizophrenia etc. Numerous drug delivery strategies have been developed to circumvent this barrier. Out of those, one popular approach is the use of nanoparticles. Nanoparticles form solid, colloidal drug delivery system that consists of macromolecular materials in which the active principle is dissolved, entrapped or encapsulated or onto which the active principle is adsorbed or attached. Brain targeted polymeric nanoparticles have been found to increase the therapeutic efficacy and reduce the toxicity for a large number of drugs. By coating the nanoparticles with surfactants, higher concentrations of the drugs can be delivered. The article presents various approaches used in design and delivery of nanoparticles to brain. It also reviews various patents that describe the use of nanoparticles to deliver various neurotherapeutics to brain.

Transglutaminases are ubiquitous enzymes which catalyze post-translational modifications of proteins. The main activity of these enzymes is the cross-linking of glutaminyl residues of a protein/peptide substrate to lysyl residues of a protein/peptide co-substrate. In addition to lysyl residues, other second nucleophilic co-substrates may include monoamines or polyamines (to form mono- or bi-substituted /crosslinked adducts) or –OH groups (to form ester linkages). In absence of co-substrates, the nucleophile may be water, resulting in the net deamidation of the glutaminyl residue. Transglutaminase activity has been suggested to be involved in molecular mechanisms responsible for both physiological or pathological processes. For example, neurodegenerative diseases, such as Alzheimer’s Disease, Parkinson’s Disease, supranuclear palsy, Huntington’s Disease and other polyglutamine diseases, are characterized in part by aberrant cerebral transglutaminase activity and by increased cross-linked proteins in affected brains. This review focuses on the possible molecular mechanisms responsible for such diseases and on the possible therapeutic effects of selective transglutaminase inhibitors for patients with diseases characterized by aberrant transglutaminase activity. The article presents some promising patents on the transglutaminase activity.