Discovery of thienopyrrolotriazine derivatives to protect mitochondrial function against Aβ-induced neurotoxicity

Discovery of Potent, Orally Bioavailable, Tricyclic NLRP3 Inhibitors

NLRP3 is a molecular sensor recognizing a wide range of danger signals. Its activation leads to the assembly of an inflammasome that allows for activation of caspase-1 and subsequent maturation of IL-1β and IL-18, as well as cleavage of Gasdermin-d and pyroptotic cell death. The NLRP3 inflammasome has been implicated in a plethora of diseases including gout, type 2 diabetes, atherosclerosis, Alzheimer's disease, and cancer. In this publication, we describe the discovery of a novel, tricyclic, NLRP3-binding scaffold by high-throughput screening. The hit (1) could be optimized into an advanced compound NP3-562 demonstrating excellent potency in human whole blood and full inhibition of IL-1β release in a mouse acute peritonitis model at 30 mg/kg po dose. An X-ray structure of NP3-562 bound to the NLRP3 NACHT domain revealed a unique binding mode as compared to the known sulfonylurea-based inhibitors. In addition, NP3-562 shows also a good overall development profile.

Discovery of Triazinone Derivatives as Novel, Specific, and Direct NLRP3 Inflammasome Inhibitors for the Treatment of DSS-Induced Ulcerative Colitis

NLRP3 is an intracellular sensor protein that causes inflammasome formation and pyroptosis in response to a wide range of stimuli. Aberrant activation of NLRP3 inflammasome has been implicated in various chronic inflammatory diseases, making it a promising target for therapeutic intervention. In this work, a series of novel triazinone inhibitors of NLRP3 inflammasome were designed and synthesized. Compound L38 was identified for its excellent activity and acceptable metabolic stability among 41 compounds. Additionally, mechanism studies indicated that L38 inhibited NLRP3 inflammasome activation and pyroptosis by suppressing gasdermin D cleavage, ASC oligomerization, and NLRP3 inflammasome assembly while leaving mitochondrial ROS production, lysosome damage, and chloride/potassium efflux unaffected. Further investigation revealed that L38 could bind to the NACHT domain to exert inflammatory properties. Importantly, L38 exhibited positive therapeutic effects in DSS-induced ulcerative colitis mouse model. Taken together, this study presents a promising inhibitor of NLRP3 inflammasome deserving further investigation.

Development of new treatments for Alzheimer's disease based on the modulation of translocator protein (TSPO)

The increase in life expectancy of the world population is associated with a higher prevalence of neurodegenerative diseases. Alzheimer's Disease (AD) is the most common neurodegenerative disease, affecting currently 43 million people over the world. To date, most of the pharmacological interventions in AD are intended for the alleviation of some of its symptoms, and there are no effective treatments to inhibit the progression of the disease. Translocator protein (TSPO) is present in contact points between the outer and the inner mitochondrial membranes and is involved in the control of steroidogenesis, inflammation and apoptosis. In the last decade, studies have shown that TSPO ligands present neuroprotective effects in different experimental models of AD, both in vitro and in vivo. The aim of this review is to analyze the data provided by these studies and to discuss if TSPO could be a viable therapeutic target for the development of new treatments for AD.