Synthesis, Pharmacological Profile and Docking Studies of New Sulfonamides Designed as Phosphodiesterase-4 Inhibitors

PLoS One. 2016 Oct 3;11(10):e0162895. doi: 10.1371/journal.pone.0162895. eCollection 2016.

Abstract

Prior investigations showed that increased levels of cyclic AMP down-regulate lung inflammatory changes, stimulating the interest in phosphodiesterase (PDE)4 as therapeutic target. Here, we described the synthesis, pharmacological profile and docking properties of a novel sulfonamide series (5 and 6a-k) designed as PDE4 inhibitors. Compounds were screened for their selectivity against the four isoforms of human PDE4 using an IMAP fluorescence polarized protocol. The effect on allergen- or LPS-induced lung inflammation and airway hyper-reactivity (AHR) was studied in A/J mice, while the xylazine/ketamine-induced anesthesia test was employed as a behavioral correlate of emesis in rodents. As compared to rolipram, the most promising screened compound, 6a (LASSBio-448) presented a better inhibitory index concerning PDE4D/PDE4A or PDE4D/PDE4B. Accordingly, docking analyses of the putative interactions of LASSBio-448 revealed similar poses in the active site of PDE4A and PDE4C, but slight unlike orientations in PDE4B and PDE4D. LASSBio-448 (100 mg/kg, oral), 1 h before provocation, inhibited allergen-induced eosinophil accumulation in BAL fluid and lung tissue samples. Under an interventional approach, LASSBio-448 reversed ongoing lung eosinophilic infiltration, mucus exacerbation, peribronchiolar fibrosis and AHR by allergen provocation, in a mechanism clearly associated with blockade of pro-inflammatory mediators such as IL-4, IL-5, IL-13 and eotaxin-2. LASSBio-448 (2.5 and 10 mg/kg) also prevented inflammation and AHR induced by LPS. Finally, the sulfonamide derivative was shown to be less pro-emetic than rolipram and cilomilast in the assay employed. These findings suggest that LASSBio-448 is a new PDE4 inhibitor with marked potential to prevent and reverse pivotal pathological features of diseases characterized by lung inflammation, such as asthma.

MeSH terms

  • Animals
  • Catalytic Domain
  • Cyclic AMP / analysis
  • Cyclic Nucleotide Phosphodiesterases, Type 4 / drug effects
  • Cyclic Nucleotide Phosphodiesterases, Type 4 / metabolism
  • Eosinophil Peroxidase / metabolism
  • Guinea Pigs
  • Humans
  • Inflammation / drug therapy
  • Lung / drug effects
  • Lung / enzymology
  • Male
  • Mice
  • Molecular Docking Simulation / methods
  • Muscle Contraction / drug effects
  • Muscle, Smooth / chemistry
  • Muscle, Smooth / drug effects
  • Peroxidase / metabolism
  • Phosphodiesterase 4 Inhibitors / chemical synthesis
  • Phosphodiesterase 4 Inhibitors / pharmacology*
  • Protein Isoforms / drug effects
  • Respiratory Hypersensitivity / drug therapy
  • Sulfonamides / chemical synthesis
  • Sulfonamides / pharmacology*
  • Trachea / drug effects

Substances

  • Phosphodiesterase 4 Inhibitors
  • Protein Isoforms
  • Sulfonamides
  • Cyclic AMP
  • Eosinophil Peroxidase
  • Peroxidase
  • Cyclic Nucleotide Phosphodiesterases, Type 4

Grants and funding

This work was supported by CNPq, FAPERJ, FAPEAL, CAPES, and INCT-INOFAR (573.564/2008-6 and E-26/170.020/2008). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.