A Novel and Cross-Species Active Mammalian INDY (NaCT) Inhibitor Ameliorates Hepatic Steatosis in Mice with Diet-Induced Obesity.

Mammalian INDY (mINDY, NaCT, gene symbol SLC13A5) is a potential target for the treatment of metabolically associated fatty liver disease (MAFLD). This study evaluated the effects of a selective, cross-species active, non-competitive, non-substrate-like inhibitor of NaCT. First, the small molecule inhibitor ETG-5773 was evaluated for citrate and succinate uptake and fatty acid synthesis in cell lines expressing both human NaCT and mouse Nact. Once its suitability was established, the inhibitor was evaluated in a diet-induced obesity (DIO) mouse model. DIO mice treated with 15 mg/kg compound ETG-5773 twice daily for 28 days had reduced body weight, fasting blood glucose, and insulin, and improved glucose tolerance. Liver triglycerides were significantly reduced, and body composition was improved by reducing fat mass, supported by a significant reduction in the expression of genes for lipogenesis such as SREBF1 and SCD1. Most of these effects were also evident after a seven-day treatment with the same dose. Further mechanistic investigation in the seven-day study showed increased plasma ß-hydroxybutyrate and activated hepatic adenosine monophosphate-activated protein kinase (AMPK), reflecting findings from Indy (-/-) knockout mice. These results suggest that the inhibitor ETG-5773 blocked citrate uptake mediated by mouse and human NaCT to reduce liver steatosis and body fat and improve glucose regulation, proving the concept of NaCT inhibition as a future liver treatment for MAFLD.

Small molecule inhibitors that discriminate between protein arginine N-methyltransferases PRMT1 and CARM1.

Protein arginine N-methyltransferases (PRMTs) selectively replace N-H for N-CH(3) at substrate protein guanidines, a post-translational modification important for a range of biological processes, such as epigenetic regulation, signal transduction and cancer progression. Selective chemical probes are required to establish the dynamic function of individual PRMTs. Herein, model inhibitors designed to occupy PRMT binding sites for an arginine substrate and S-adenosylmethionine (AdoMet) co-factor are described. Expedient access to such compounds by modular synthesis is detailed. Remarkably, biological evaluation revealed some compounds to be potent inhibitors of PRMT1, but inactive against CARM1. Docking studies show how prototype compounds may occupy the binding sites for a co-factor and arginine substrate. Overlay of PRMT1 and CARM1 binding sites suggest a difference in a single amino acid that may be responsible for the observed selectivity.

Closed Pantalar Dislocation With Checkrein Deformity: A Unique Case Report and Literature Review.

Closed pantalar dislocations are a rare variant of an uncommon injury. Pantalar dislocations are typically caused by high-energy trauma resulting in an open injury with associated fracture of the articulating bones. Given its obscurity, the literature on closed pantalar dislocations is scarce, and no standard treatment protocol has been accepted. This case report chronicles the treatment and outcome of a 29-year-old man who presented with a checkrein deformity of all digits after a closed pantalar dislocation with 6-month follow-up. A comprehensive literature review found 28 articles representing 39 patients with closed pantalar dislocations without talar neck or body fractures. Roughly equal numbers of closed and open reduction techniques were performed with avascular necrosis occurring in 7 of 36 patients. Although outcome measures and follow-up were variable, what can be considered a suitable outcome was seen in approximately 83% of patients, with only 3 of 35 requiring a secondary operation. Long-term studies with well-defined outcome measures are needed to adequately predict the prognosis of this rare injury and efficacy of treatment protocols.

Toward the development of potent and selective bisubstrate inhibitors of protein arginine methyltransferases.

Prototype inhibitors of protein arginine methyltransferases (PRMTs) have been constructed by attaching guanidine functionality via a variable linker to non-reactive amine analogues of the cellular co-factor (S)-adenosyl methionine (AdoMet). Potent inhibition of PRMT1 (IC(50) of approximately 3-6 microM) combined with weak inhibition of the lysine methyltransferase SET7 (approximately 50% of activity at 100 microM) was observed for two such compounds.

A one-pot process for the enantioselective synthesis of amines via reductive amination under transfer hydrogenation conditions.

[reaction: see text]. Cyclic amines may be prepared via a sequence of deprotection followed by intramolecular reductive amination of t-Boc-protected amino ketones under asymmetric transfer hydrogenation conditions. In cases where the corresponding imine reaction proceeds with high enantioselectivity, this is reflected in the one-step process.

Binding mode and structure-activity relationships around direct inhibitors of the Nrf2-Keap1 complex.

An X-ray crystal structure of Kelch-like ECH-associated protein (Keap1) co-crystallised with (1S,2R)-2-[(1S)-1-[(1,3-dioxo-2,3-dihydro-1H-isoindol-2-yl)methyl]-1,2,3,4-tetrahydroisoquinolin-2-carbonyl]cyclohexane-1-carboxylic acid (compound (S,R,S)-1 a) was obtained. This X-ray crystal structure provides breakthrough experimental evidence for the true binding mode of the hit compound (S,R,S)-1 a, as the ligand orientation was found to differ from that of the initial docking model, which was available at the start of the project. Crystallographic elucidation of this binding mode helped to focus and drive the drug design process more effectively and efficiently.

trans-2,5-Disubstituted pyrrolidines: Rapid stereocontrolled access from sulfones.

A direct and versatile route for the reliable synthesis of trans-2,5-disubstituted pyrrolidines from pyroglutamic acid is reported, which can be conducted at scale and without chromatographic purification of key intermediates.

A qualitative study of amlodipine and its related compounds by electrospray ionization tandem mass spectrometry.

A comprehensive structural analysis of amlodipine and certain related compounds was performed by electrospray ionization tandem mass spectrometry. Triple quadrupole and quadrupole time-of-flight instruments were used to provide collision-induced dissociation and accurate mass measurement for selected product and second-generation product ions. A unique ion rearrangement was observed, which was found to be characteristic of certain dihydropyridines. This study provides a fundamental understanding of the fragmentation of these compounds. The structural elucidation of an unknown impurity is presented as an example.