Innovative Non-PrP-Targeted Drug Strategy Designed to Enhance Prion Clearance

Prion diseases are a group of neurodegenerative disorders characterized by the accumulation of misfolded prion protein (called PrPSc). Although conversion of the cellular prion protein (PrPC) to PrPSc is still not completely understood, most of the therapies developed until now are based on blocking this process. Here, we propose a new drug strategy aimed at clearing prions without any direct interaction with neither PrPC nor PrPSc. Starting from the recent discovery of SERPINA3/SerpinA3n upregulation during prion diseases, we have identified a small molecule, named compound 5 (ARN1468), inhibiting the function of these serpins and effectively reducing prion load in chronically infected cells. Although the low bioavailability of this compound does not allow in vivo studies in prion-infected mice, our strategy emerges as a novel and effective approach to the treatment of prion disease

Distinctive lipid signatures of bronchial epithelial cells associated with cystic fibrosis drugs, including Trikafta

In recent years, a number of drugs have been approved for the treatment of cystic fibrosis (CF). Among them, newly released Trikafta, a combination of 3 drugs (VX-661/VX-445/VX-770), holds great promise to radically improve the quality of life for a large portion of patients with CF carrying 1 copy of F508del, the most frequent CF transmembrane conductance regulator (CFTR) mutation. Currently available disease-modifying CF drugs work by rescuing the function of the mutated CFTR anion channel. Recent research has shown that membrane lipids, and the cell lipidome in general, play a significant role in the mechanism of CFTR-defective trafficking and, on the other hand, its rescue. In this paper, by using untargeted lipidomics on CFBE41o- cells, we identified distinctive changes in the bronchial epithelial cell lipidome associated with treatment with Trikafta and other CF drugs. Particularly interesting was the reduction of levels of ceramide, a known molecular player in the induction of apoptosis, which appeared to be associated with a decrease in the susceptibility of cells to undergo apoptosis. This evidence could account for additional beneficial roles of the triple combination of drugs on CF phenotypes

Potent multitarget FAAH-COX inhibitors: Design and structure-activity relationship studies.

Non-steroidal anti-inflammatory drugs (NSAIDs) exert their pharmacological effects by inhibiting cyclooxygenase (COX)-1 and COX-2. Though widely prescribed for pain and inflammation, these agents have limited utility in chronic diseases due to serious mechanism-based adverse events such as gastrointestinal damage. Concomitant blockade of fatty acid amide hydrolase (FAAH) enhances the therapeutic effects of the NSAIDs while attenuating their propensity to cause gastrointestinal injury. This favorable interaction is attributed to the accumulation of protective FAAH substrates, such as the endocannabinoid anandamide, and suggests that agents simultaneously targeting COX and FAAH might provide an innovative strategy to combat pain and inflammation with reduced side effects. Here, we describe the rational design and structure-active relationship (SAR) properties of the first class of potent multitarget FAAH-COX inhibitors. A focused SAR exploration around the prototype 10r (ARN2508) led to the identification of achiral (18b) as well as racemic (29a-c and 29e) analogs. Absolute configurational assignment and pharmacological evaluation of single enantiomers of 10r are also presented. (S)-(+)-10r is the first highly potent and selective chiral inhibitor of FAAH-COX with marked in vivo activity, and represents a promising lead to discover novel analgesics and anti-inflammatory drugs

Potent multitarget FAAH-COX inhibitors: Design and structure-activity relationship studies.

Non-steroidal anti-inflammatory drugs (NSAIDs) exert their pharmacological effects by inhibiting cyclooxygenase (COX)-1 and COX-2. Though widely prescribed for pain and inflammation, these agents have limited utility in chronic diseases due to serious mechanism-based adverse events such as gastrointestinal damage. Concomitant blockade of fatty acid amide hydrolase (FAAH) enhances the therapeutic effects of the NSAIDs while attenuating their propensity to cause gastrointestinal injury. This favorable interaction is attributed to the accumulation of protective FAAH substrates, such as the endocannabinoid anandamide, and suggests that agents simultaneously targeting COX and FAAH might provide an innovative strategy to combat pain and inflammation with reduced side effects. Here, we describe the rational design and structure-active relationship (SAR) properties of the first class of potent multitarget FAAH-COX inhibitors. A focused SAR exploration around the prototype 10r (ARN2508) led to the identification of achiral (18b) as well as racemic (29a-c and 29e) analogs. Absolute configurational assignment and pharmacological evaluation of single enantiomers of 10r are also presented. (S)-(+)-10r is the first highly potent and selective chiral inhibitor of FAAH-COX with marked in vivo activity, and represents a promising lead to discover novel analgesics and anti-inflammatory drugs

Synthesis, structure-activity, and structure-stability relationships of 2-substituted-N-(4-oxo-3-oxetanyl) N-acylethanolamine acid amidase (NAAA) inhibitors.

N-Acylethanolamine acid amidase (NAAA) is a cysteine amidase that preferentially hydrolyzes saturated or monounsaturated fatty acid ethanolamides (FAEs), such as palmitoylethanolamide (PEA) and oleoylethanolamide (OEA), which are endogenous agonists of nuclear peroxisome proliferator-activated receptor-α (PPAR-α). Compounds that feature an α-amino-β-lactone ring have been identified as potent and selective NAAA inhibitors and have been shown to exert marked anti-inflammatory effects that are mediated through FAE-dependent activation of PPAR-α. We synthesized and tested a series of racemic, diastereomerically pure β-substituted α-amino-β-lactones, as either carbamate or amide derivatives, investigating the structure-activity and structure-stability relationships (SAR and SSR) following changes in β-substituent size, relative stereochemistry at the α- and β-positions, and α-amino functionality. Substituted carbamate derivatives emerged as more active and stable than amide analogues, with the cis configuration being generally preferred for stability. Increased steric bulk at the β-position negatively affected NAAA inhibitory potency, while improving both chemical and plasma stability

Potent α-amino-β-lactam carbamic acid ester as NAAA inhibitors. Synthesis and structure-activity relationship (SAR) studies.

4-Cyclohexylbutyl-N-[(S)-2-oxoazetidin-3-yl]carbamate (3b) is a potent, selective and systemically active inhibitor of intracellular NAAA activity, which produces profound anti-inflammatory effects in animal models. In the present work, we describe structure-activity relationship (SAR) studies on 3-aminoazetidin-2-one derivatives, which have led to the identification of 3b, and expand these studies to elucidate the principal structural and stereochemical features needed to achieve effective NAAA inhibition. Investigations on the influence of the substitution at the β-position of the 2-oxo-3-azetidinyl ring as well as on the effect of size and shape of the carbamic acid ester side chain led to the discovery of 3ak, a novel inhibitor of human NAAA that shows an improved physicochemical and drug-like profile relative to 3b. This favourable profile, along with the structural diversity of the carbamic acid chain of 3b, identify this compound as a promising new tool to investigate the potential of NAAA inhibitors as therapeutic agents for the treatment of pain and inflammation

Potent α-amino-β-lactam carbamic acid ester as NAAA inhibitors. Synthesis and structure-activity relationship (SAR) studies.

4-Cyclohexylbutyl-N-[(S)-2-oxoazetidin-3-yl]carbamate (3b) is a potent, selective and systemically active inhibitor of intracellular NAAA activity, which produces profound anti-inflammatory effects in animal models. In the present work, we describe structure-activity relationship (SAR) studies on 3-aminoazetidin-2-one derivatives, which have led to the identification of 3b, and expand these studies to elucidate the principal structural and stereochemical features needed to achieve effective NAAA inhibition. Investigations on the influence of the substitution at the β-position of the 2-oxo-3-azetidinyl ring as well as on the effect of size and shape of the carbamic acid ester side chain led to the discovery of 3ak, a novel inhibitor of human NAAA that shows an improved physicochemical and drug-like profile relative to 3b. This favourable profile, along with the structural diversity of the carbamic acid chain of 3b, identify this compound as a promising new tool to investigate the potential of NAAA inhibitors as therapeutic agents for the treatment of pain and inflammation

Identification and characterization of carprofen as a multitarget fatty acid amide hydrolase/cyclooxygenase inhibitor.

Pain and inflammation are major therapeutic areas for drug discovery. Current drugs for these pathologies have limited efficacy, however, and often cause a number of unwanted side effects. In the present study, we identify the nonsteroidal anti-inflammatory drug carprofen as a multitarget-directed ligand that simultaneously inhibits cyclooxygenase-1 (COX-1), COX-2, and fatty acid amide hydrolase (FAAH). Additionally, we synthesized and tested several derivatives of carprofen, sharing this multitarget activity. This may result in improved analgesic efficacy and reduced side effects (Naidu et al. J. Pharmacol. Exp. Ther.2009, 329, 48-56; Fowler, C. J.; et al. J. Enzyme Inhib. Med. Chem.2012, in press; Sasso et al. Pharmacol. Res.2012, 65, 553). The new compounds are among the most potent multitarget FAAH/COX inhibitors reported so far in the literature and thus may represent promising starting points for the discovery of new analgesic and anti-inflammatory drugs

Identification and characterization of carprofen as a multitarget fatty acid amide hydrolase/cyclooxygenase inhibitor.

Pain and inflammation are major therapeutic areas for drug discovery. Current drugs for these pathologies have limited efficacy, however, and often cause a number of unwanted side effects. In the present study, we identify the nonsteroidal anti-inflammatory drug carprofen as a multitarget-directed ligand that simultaneously inhibits cyclooxygenase-1 (COX-1), COX-2, and fatty acid amide hydrolase (FAAH). Additionally, we synthesized and tested several derivatives of carprofen, sharing this multitarget activity. This may result in improved analgesic efficacy and reduced side effects (Naidu et al. J. Pharmacol. Exp. Ther.2009, 329, 48-56; Fowler, C. J.; et al. J. Enzyme Inhib. Med. Chem.2012, in press; Sasso et al. Pharmacol. Res.2012, 65, 553). The new compounds are among the most potent multitarget FAAH/COX inhibitors reported so far in the literature and thus may represent promising starting points for the discovery of new analgesic and anti-inflammatory drugs

Pharmacological Inhibition of the Ubiquitin Ligase RNF5 Rescues F508del-CFTR in Cystic Fibrosis Airway Epithelia

In cystic fibrosis (CF), deletion of phenylalanine 508 (F508del) in the CFTR channel is associated with misfolding and premature degradation of the mutant protein. Among the known proteins associated with F508del-CFTR processing, the ubiquitin ligase RNF5/RMA1 is particularly interesting. We previously demonstrated that genetic suppression of RNF5 in vivo leads to an attenuation of intestinal pathological phenotypes in CF mice, validating the relevance of RNF5 as a drug target for CF. Here, we used a computational approach, based on ligand docking and virtual screening, to discover inh-02, a drug-like small molecule that inhibits RNF5. In in vitro experiments, treatment with inh-02 modulated ATG4B and paxillin, both known RNF5 targets. In immortalized and primary bronchial epithelial cells derived from CF patients homozygous for the F508del mutation, long-term incubation with inh-02 caused significant F508del-CFTR rescue. This work validates RNF5 as a drug target for CF, providing evidence to support its druggability. Sondo et al. used a computational approach to identify an inhibitor, named inh-02, for RNF5 ubiquitin ligase. RNF5 detects the misfolding of a mutant CFTR in cystic fibrosis. Inh-2 decreases ubiquitylation and rescues F508del-CFTR on human primary bronchial epithelia. This work validates RNF5 as a drug target for cystic fibrosis