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Pramlintide is an equipotent amylin analogue that reduces food intake and body weight in obese subjects and has been clinically approved as an adjunctive therapy for the treatment of adult diabetic patients. However, due to its extremely short half-life in vivo, a regimen of multiple daily administrations is required for achieving clinical effectiveness. Herein is described the development of prototypical long-acting pramlintide bioconjugates, in which pramlintide's disulfide-linked macrocycle was replaced by a cyclic thioether motif. This modification enabled stable chemical conjugation to a half-life extending antibody. In contrast to pramlintide (t 1/2 < 0.75 h), bioconjugates 35 and 38 have terminal half-lives of ∼2 days in mice and attain significant exposure levels that are maintained up to 7 days. Single dose subcutaneous administration of 35 in lean mice, given 18–20 h prior to oral acetaminophen (AAP) administration, significantly reduced gastric emptying (as determined by plasma AAP levels). In a separate study, similar administration of 35 in fasted lean mice effected a reduction in food intake for up to 48 h. These data are consistent with durable amylinomimetic responses and provide the basis for further development of such long-acting amylinomimetic conjugates for the potential treatment of obesity and associated pathologies. [Display omitted] • The clinical amylin receptor agonist, pramlintide, has a short half-life in vivo. • Novel thioether-based macrocyclic pramlintide analogues are described. • Bioconjugation of select analogues provided prolonged exposure levels in mice. • Bioconjugate 35 reduced gastric emptying and food uptake in mice for up to 48 h. [ABSTRACT FROM AUTHOR]

Certain leukocytes release serine proteases that sustain inflammatory processes and cause disease conditions, such as asthma and chronic obstructive pulmonary disease. We identified β-ketophosphonate 1 (JNJ10311795; RWJ-355871) as a novel, potent dual inhibitor of neutrophil cathepsin G (Ki = 38 nM) and mast cell chymase (Ki = 2.3 nM). The x-ray crystal structures of 1 complexed with human cathepsin G (1.85 Å) and human chymase (1.90 Å) reveal the molecular basis of the dual inhibition. Ligand 1 occupies the S1 and S2 subsites of cathepsin G and chymase similarly, with the 2-naphthyl in S1, the l-naphthyl in S2, and the phosphonate group in a complex network of hydrogen bonds. Surprisingly, however, the carboxamido-N-(naphthalene-2-carboxyl)piperidine group is found to bind in two distinct conformations. In cathepsin G, this group occupies the bydrophobic S3/S4 subsites, whereas in chymase, it does not; rather, it folds onto the l-naphthyl group of the inhibitor itself. Compound 1 exhibited noteworthy antiinflammatory activity in rats for glycogen-induced peritonitis and lipopolysaccharide-induced airway inflammation. In addition to a marked reduction in neutrophil influx, 1 reversed increases in inflammatory mediators interleukin-lα, interleukin-lβ, tissue necrosis factor-α, and monocyte chemotactic protein-1 in the glycogen model and reversed increases in airway nitric oxide levels in the lipopolysaccharide model. These findings demonstrate that it is possible to inhibit both cathepsin G and chymase with a single molecule and suggest an exciting opportunity in the treatment of asthma and chronic obstructive pulmonary disease. [ABSTRACT FROM AUTHOR]

Efficient methods were developed to synthesize a novel series of macrocyclic bisindolylmaleimides containing linkers with multiple heteroatoms. Potent inhibitors (single digit nanomolar IC50) for PKC-β and GSK-3β were identified, and compounds showed good selectivity over PKC-α, -γ, -δ, -&epsiv;, and -ζ. Representative compound 5a also had high selectivity in a screening panel of 10 other protein kinases. In cell-based functional assays, several compounds effectively blocked interleukin-8 release induced by PKC-βII and increased glycogen synthase activity by inhibiting GSK-3β. [Copyright &y& Elsevier]