Recent Patents on CNS Drug Discovery (Discontinued) - Current Issue

Background: Peptides are usually used to investigate regulatory networks and protein function. They can also be used in therapeutic research: They are employed both to identify and later to validate therapeutical target and in drug discovery processes. Their development enables the identification of several protein surfaces as crucial therapeutic targets and to promote the discovery of small drugs specific for these molecular interfaces. Methods: This review was developed through the research of online content and patents related to natural and de novo designed peptides in neurological diseases studies. The effects of natural and derived peptides and/or peptidomimetic on models of neurodegenerative diseases and other neurological disorders were discussed. Results: Many peptides are frequently identified as receptor antagonists, inhibitors of protein–protein interactions and several of them and/or peptide-derived compounds are commercial drugs or in clinical trials. Thus, peptide research could play a crucial role in the identification of protein ligands. Despite these favorable properties, they present low bioavailability and metabolic stability respect with traditional drugs. New synthetic strategies for limiting metabolic degradation and alternative routes of administration have been conceived to enlarge the number of peptide-based drugs in preclinical phases. Conclusion: Peptide-based drug discovery is an important option to address common therapeutic challenges including human neurological diseases.

Background: Several studies support the evidence that the endocannabinoid system and cannabimimetic drugs might have therapeutic potential in numerous pathologies. These pathologies range from neurological disorders, atherosclerosis, stroke, cancer to obesity/metabolic syndrome and others. Methods: In this paper we review the endocannabinoid system signaling and its alteration in neurodegenerative disorders like multiple sclerosis, Alzheimer’s disease, Parkinson’s disease and Huntington’s disease and discuss the main findings about the use of cannabinoids in the therapy of these pathologies. Results: Despite different etiologies, neurodegenerative disorders exhibit similar mechanisms like neuro-inflammation, excitotoxicity, deregulation of intercellular communication, mitochondrial dysfunction and disruption of brain tissue homeostasis. Current treatments ameliorate the symptoms but are not curative. Interfering with the endocannabinoid signaling might be a valid therapeutic option in neuro-degeneration. To this aim, pharmacological intervention to modulate the endocannabinoid system and the use of natural and synthetic cannabimimetic drugs have been assessed. CB1 and CB2 receptor signaling contributes to the control of Ca2+ homeostasis, trophic support, mitochondrial activity, and inflammatory conditions. Conclusion: Several studies and patents suggest that the endocannabinoid system has neuro-protective properties and might be a target in neurodegenerative diseases.

Background: We have recently released the structure of a class of quinolin-2-(1H)-on-3-carboxamide derivatives and among them; the drug A2 has the highest CB2 receptor selectivity. Objective: In this work we assessed the immuno-modulatory properties of A2 in lymphocytes isolated from peripheral blood of multiple sclerosis patients and healthy donors. Methods: Cell proliferative response was measured by 3H-thymidine incorporation, cell viability and apoptosis by trypan blue, annexin V staining and western blot. Cell activation was investigated by flow cytometry and molecular pathways by western blot. Results: A2 exerted anti-proliferative effects with down-regulation of TNF-α, IL-10 and Rantes in both cell types. No relevant changes were observed in cell viability between the two cell types. In cells from healthy subjects, A2 did not induce apoptosis, inhibited the cell cycle and similarly down-regulated in CD4+T cells the markers CD69, CD25, CD49d and CD54. Indeed, A2 also inhibited the phosphorylation of Akt, NF-kB, IKKα/β, ERK and blocked the expression of Cox-2 and CB2 receptor. Published patents also describe CB2 receptor agonists like purine derivatives. Differently, in cells from patients, A2 did not affect CD49d, while potently blocked CD54 expression. A2 inhibitory effects of Akt and Cox-2 expression were confirmed, whereas unchanged level of the CB2 receptor was observed in these cells. Conclusion: We reported similar effects of A2 in both cell types; however, a different mechanism of action might be suggested in cells from patients concerning cell activation and CB2 receptor expression. Overall, these data suggest an anti-inflammatory profile of A2 with potential implication in multiple sclerosis.

Background: Anandamide (AEA) and 2-arachidonoyl glycerol (2-AG) are signalling lipids which belong to the class of endocannabinoids (ECs) and exert their actions by activating cannabinoid receptor type-1 (CB1) and type-2 (CB2). These receptors are involved in many physiological and pathological processes in the central nervous system (CNS) and in peripheral organs. Despite many potent and selective ligands for cannabinoid receptors have been generated over the last two decades, this class of compounds achieved only a very limited therapeutic success, mainly because of the CB1- mediated side effects. Methods: The compounds and results presented in this review article have been gathered from an extensive research in public databases for patents, clinical trials and scientific literature. Reference to patent numbers, clinical trial registry numbers, websites and scientific articles is provided in the text and/or in the reference section. Results: Over the last 10-15 years, many inhibitors for the main EC hydrolytic enzymes fatty acid amide hydrolase (FAAH), monoacylglycerol lipase (MAGL), α,β-hydrolase domain-6 (ABHD6) and -12 (ABHD12) have been synthesized and characterized in vitro and in vivo. Additionally, other targets have been explored for the modulation of the endocannabinoid system (ECS). Among them, several novel inhibitors for COX-2, diacylglycerol lipases and the putative endocannabinoid membrane transporter have been described in the literature. Polypharmacological approaches which combine mild or reversible inhibition of at least two of these targets are also under investigation. Conclusions: The ECS offers several therapeutic opportunities beyond the direct activation of cannabinoid receptors. The modulation of EC levels in vivo represents an interesting therapeutic perspective for several CNS-related diseases. Based on the literature and patent literature this review provides an overview of the different classes of inhibitors for FAAH, MAGL, ABHDs and COX-2 used as tool compounds and for clinical development with a special focus on CNS-related diseases.

Background: Since the discovery of the cannabinoid receptors, numerous studies associate the endocannabinoid system with several physiological and pathological processes including cancer, appetite, fertility, memory, neuropathic and inflammatory pain, obesity, and neurodegenerative diseases. Over the last two decades, several researches have been dedicated extensively on the cannabinoid receptors ligands since the direct activation of cannabinoid receptors results in several beneficial effects, in the brain and in the periphery. The cannabinoid CB1 and CB2 receptor synthetic ligands reported in this review have been collected by a wide research of scientific literature in particular in public database for patents and clinical trials. The references for patent numbers, clinical trial registry numbers, websites and scientific articles are reported in the reference section. Results: During past years, cannabinoid CB1 and CB2 receptor ligands from plants or lab were rapidly developed and then various new structures were reported to be cannabinoids. However the CB1 receptor ligands have had a limited usefulness due to their psychotropic effects, dependence, and cognitive impairment. On the contrary the development of CB2 receptor ligands has been more productive. Furthermore peripherally restricted agonists as well as CB1 receptor positive or negative allosteric modulators were studied with the aim of eliminating the undesirable CB1 receptor central effects. Conclusions: The CB1 and CB2 receptor ligands offer several therapeutic opportunities for several CNS-related diseases. Based on the scientific literature, this review provides an overview of CB1 and CB2 receptor synthetic ligands obtained from drug research and in particular those synthesized for therapeutic purposes and potential clinical applications for central nervous system disorders.

Background: Starting from the chemical structure of phytocannabinoids, isolated from Cannabis sativa plant, research groups designed numerous cannabimimetic drugs. These compounds according to their activities can be partial, full agonists and antagonists of cannabinoid receptors. Anecdotal reports and scientific studies described beneficial properties of cannabinoids and their derivatives in several pathological conditions like neurological and neuropsychiatric disorders, and in many other diseases ranging from cancer, atherosclerosis, stroke, hypertension, inflammatory related disorders, and autoimmune diseases. Methods: In this study, starting from the endocannabinoid mechanism of action in neuronal signaling, we highlight and discuss potential application and recent patents of cannabimimetic drugs in neurological disorders. Results: The cannabinoid CB1 receptor was considered particularly interesting for therapeutic approaches in neurological diseases, because primarily expressed by neurons of the central nervous system. In many experimental models, these drugs act via this receptor, however, CB1 receptor independent mechanisms have been also described. Furthermore, endogenous ligands of cannabinoid receptors, the endocannabinoids, are potent modulators of the synaptic function in the brain. In neurological diseases, numerous studies reported modulation of the levels of endocannabinoids according to the phase of the disease and its progression. Conclusions: Finally, although the study of the mechanisms of action of these compounds is still unsolved, many reports and patents strongly suggest therapeutic potential of these compounds in neurological diseases.

Background: Cannabinoid receptors are involved in the neuro-pathogenic mechanisms of inflammatory conditions of the central nervous system and their expression can be modulated during diseases. Methods: In this manuscript we highlight the function of cannabinoid receptors, their signalling and expression at peripheral and central levels in order to understand their implication in neuro-inflammation and review the effects of cannabinoids in neuro-inflammatory disorders. Results: Brain inflammatory processes are characterized by infiltration of numerous types of cells: both peripheral and brain resident immune cells and other neuronal cells. The disruption of the blood brain barrier favours cell infiltration in the central nervous system with consequent neuronal damage, a common event in many neuro-inflammatory diseases. Cannabinoids affect brain adaptive and immune response, regulate inflammatory mediators and can exert a role in blood brain barrier damage prevention. Conclusion: Various patents describe the beneficial properties of cannabinoids in numerous neurodegenerative diseases with inflammatory components and overall effects support the therapeutic application of cannabinoids.

Background: Owing to the increasing aged population globally, disorders and diseases of the CNS are anticipated to increase and profoundly impact the health care. As these neurodegenerative diseases (NDD) are complex, multifactorial and do not have identified etiological factors, unfortunately, drugs developed for the purpose have not met with the expected success. Hence, there has been a constant demand for the development of natural therapeutic adjuvants which are safe and possess the potential to attenuate multiple pathways. Methods: Numerous herbal/natural products have been used as therapeutics in Ayurvedic system of medicine to treat NDD and other memory-related disorders. Withania somnifera (Ashwagandha, WS), popularly called as “Indian Ginseng” is one such plant which possesses a variety of beneficial neuropharmacological properties. In this review, we have attempted to review critically the existing literature and patents related to the neuroprotective efficacy of WS roots and the underlying mechanism/s. Results: Standardized extracts of Withania somnifera (WS) have been demonstrated to possess multidimensional neuromodulatory effects both in vitro and animal models. The spectrum of effects evidenced comprises of attenuation of oxidative damage by enhancing the antioxidant defense system with concomitant enhancement of the expression of marker proteins responsible for growth, differentiation and communication of neural cells. Specific effects of WS are attributable to its potential to modulate neurotrophic factors, cytoskeletal elements, cell adhesion molecules and synaptic proteins. Conclusion: Generation of new data by employing systematic contemporary approaches such as bioinformatics, molecular docking studies, identification of specific gene targets and epigenetic regulation would provide the necessary impetus to validate fully the neurotherapeutic potential of the phytochemicals derived from WS. More importantly, well-designed clinical trials are required to exploit the neuromodulatory propensity of WS extract/bioactives in specific neurodegenerative diseases such as AD and PD.