Novel benzothiazole derivatives as multitargeted-directed ligands for the treatment of Alzheimer's disease.

Neurodegenerative diseases such as Alzheimer's disease (AD) are multifactorial with several different pathologic mechanisms. Therefore, it is assumed that multitargeted-directed ligands (MTDLs) which interact with different biological targets relevant to the diseases, might offer an improved therapeutic alternative than using the traditional "one-target, one-molecule" approach. Herein, we describe new benzothiazole-based derivatives as a privileged scaffold for histamine H3 receptor ligands (H3R). The most affine compound, the 3-(azepan-1-yl)propyloxy-linked benzothiazole derivative 4b, displayed a Ki value of 0.012 µM. The multitargeting potential of these H3R ligands towards AChE, BuChE and MAO-B enzymes was evaluated to yield compound 3s (pyrrolidin-1-yl-(6-((5-(pyrrolidin-1-yl)pentyl)oxy)benzo[d]thiazol-2-yl)methanone) as the most promising MTDL with a Ki value of 0.036 µM at H3R and IC50 values of 6.7 µM, 2.35 µM, and 1.6 µM towards AChE, BuChE, and MAO-B, respectively. These findings suggest that compound 3s can be a lead structure for developing new multi-targeting anti-AD agents.

Novel 9-Benzylaminoacridine Derivatives as Dual Inhibitors of Phosphodiesterase 5 and Topoisomerase II for the Treatment of Colon Cancer.

It has been shown that phosphodiesterase 5 (PDE5) inhibitors have anticancer effects in a variety of malignancies in both in vivo and in vitro experiments. The role of cGMP elevation in colorectal carcinoma (CRC) has been extensively studied. Additionally, DNA topoisomerase II (Topo II) inhibition is a well-established mechanism of action that mediates the effects of several approved anticancer drugs such as doxorubicin and mitoxantrone. Herein, we present 9-benzylaminoacridine derivatives as dual inhibitors of the PDE5 and Topo II enzymes. We synthesized 31 derivatives and evaluated them against PDE5, whereby 22 compounds showed micromolar or sub-micromolar inhibition. The anticancer activity of the compounds was evaluated with the NCI 60-cell line testing. Moreover, the effects of the compounds on HCT-116 colorectal carcinoma (CRC) were extensively studied, and potent compounds against HCT-116 cells were studied for their effects on Topo II, cell cycle progression, and apoptosis. In addition to exhibiting significant growth inhibition against HCT116 cells, compounds 11, 12, and 28 also exhibited the most superior Topo II inhibitory activity and low micromolar PDE5 inhibition and affected cell cycle progression. Knowing that compounds that combat cancer through multiple mechanisms are among the best candidates for effective therapy, we believe that the current class of compounds merits further optimization and investigation to unleash their full therapeutic potential.

Apremilast ameliorates acute respiratory distress syndrome by inhibiting neutrophil-induced oxidative stress.

BACKGROUND: The pathogenesis of acute respiratory distress syndrome (ARDS) is attributed to the dysregulation of oxidative stress and neutrophil recruitment. We aimed to investigate the anti-inflammatory effects of apremilast on human neutrophils and assess its efficacy for treating ARDS. METHODS: We analysed superoxide anion generation, integrin expression, and adhesion in activated human neutrophils using spectrophotometry, flow cytometry, and immunofluorescence microscopy. Phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) was determined using immunoblotting. A murine lipopolysaccharide (LPS)-induced ARDS model was used to evaluate the therapeutic effects of apremilast. RESULTS: Apremilast significantly decreased superoxide anion production, reactive oxygen species (ROS) generation, cluster of differentiation (CD)11 b expression, and neutrophil adhesion in formyl-l-methionyl-l-leucyl-l-phenylalanine activated human neutrophils. Apremilast elevated cyclic 3',5'-adenosine monophosphate (cAMP) and protein kinase A (PKA) activity in activated neutrophils. It reduced cellular cAMP-specific phosphodiesterase (PDE) activity and selectively inhibited enzymatic PDE4 activity. The activated cAMP/PKA pathway suppressed the phosphorylation of ERK and JNK as well as Ca2+ mobilization in activated neutrophils. All inhibitory effects of apremilast on activated neutrophils were reversed by a PKA inhibitor. In vivo examinations indicated that apremilast alleviated lung neutrophil infiltration, myeloperoxidase (MPO) activity, pulmonary oedema, and alveolar damage in LPS-induced ARDS. CONCLUSION: Apremilast inhibits inflammatory responses after neutrophil activation via cAMP/PKA-dependent inhibition of ERK and JNK activation. Our study revealed apremilast suppresses oxidative stress and chemotaxis by selectively inhibiting PDE4 in neutrophils and thus protects against endotoxin-induced ARDS in mice. Apremilast can be used as an alternative off-label drug in treating acute lung damage.

Carnosic acid inhibits reactive oxygen species-dependent neutrophil extracellular trap formation and ameliorates acute respiratory distress syndrome.

AIMS: Infiltration of activated neutrophils into the lungs is a hallmark of acute respiratory distress syndrome (ARDS). Neutrophilic inflammation, particularly neutrophil extracellular traps (NETs), is proposed as a useful target for treating ARDS. Carnosic acid (CA) is a food additive; however, its anti-neutrophilic activity in the treatment of ARDS has not been well established. The hypothesis of present study is to confirm that CA alleviates ARDS by suppressing neutrophilic inflammation and oxidative damage. MAIN METHODS: Generation of superoxide anions and reactive oxygen species (ROS), induction of elastase degranulation, and formation of NETs by human neutrophils were assayed using spectrophotometry, flow cytometry, and immunofluorescent microscopy. Immunoblotting was performed to determine the cellular mechanisms involved. Cell-free radical systems were used to test antioxidant activities. The therapeutic effect of CA was evaluated in a lipopolysaccharide (LPS)-induced ARDS mouse model. KEY FINDINGS: CA greatly reduced superoxide anion production, ROS production, elastase release, cluster of differentiation 11b expression, and cell adhesion in activated human neutrophils. Mechanistic studies have demonstrated that CA suppresses phosphorylation of extracellular regulated kinase and c-Jun N-terminal kinase in activated neutrophils. CA effectively scavenges reactive oxygen and nitrogen species, but not superoxide anions. This is consistent with the finding that CA is effective against ROS-dependent NET formation. CA treatment significantly improved pulmonary neutrophil infiltration, oxidative damage, NET formation, and alveolar damage in LPS-induced mice. SIGNIFICANCE: Our data suggested the potential application of CA for neutrophil-associated ARDS therapy.

Superparamagnetic, High Magnetic α-Fe & α″-Fe16N2 Mixture Prepared from Inverse Suspension-Polymerized Fe3O4@polyaniline Composite.

Oleic acid (OA)-modified Fe3O4 nanoparticles were successfully covered with polyanilines (PANIs) via inverse suspension polymerization in accordance with SEM and TEM micrographs. The obtained nanoparticles were able to develop into a ferrite (α-Fe) and α″-Fe16N2 mixture with a superparamagnetic property and high saturated magnetization (SM) of 245 emu g-1 at 950 °C calcination under the protection of carbonization materials (calcined PANI) and other iron-compounds (α″-Fe16N2). The SM of the calcined iron-composites slightly decreases to 232 emu g-1 after staying in the open air for 3 months. The calcined mixture composite can be ground into homogeneous powders without the segregation of the iron and carbon phases in the mortar without significantly losing magnetic activities.

Imperatorin Alleviates Psoriasiform Dermatitis by Blocking Neutrophil Respiratory Burst, Adhesion, and Chemotaxis Through Selective Phosphodiesterase 4 Inhibition.

Aim: Neutrophil infiltration and increased oxidative stress are involved in the pathogenesis and severity of psoriasis. Although the therapy of psoriasis remains elusive, targeting treatment to reduce oxidative stress is considered a potential option. Our study demonstrates the anti-inflammatory effects of a natural furocoumarin, imperatorin, on activated human neutrophils and psoriasiform dermatitis in mice. Results: Imperatorin inhibited superoxide anion generation, neutrophil adhesion, and migration in N-formyl-l-methionyl-l-leucyl-l-phenylalanine (fMLF)-stimulated human neutrophils. Further studies showed that imperatorin induced a decrease in cAMP-specific phosphodiesterase (PDE) activity, and increased intracellular cAMP levels and protein kinase A (PKA) activity in human neutrophils. The enzyme activities of PDE4 subtypes, but not PDE3 and PDE7, were inhibited by imperatorin. Furthermore, imperatorin inhibited the phosphorylation of protein kinase B (Akt), extracellular regulated kinase (ERK), and c-Jun N-terminal kinase (JNK), as well as Ca2+ mobilization in fMLF-stimulated neutrophils. These suppressive effects of imperatorin on cell responses and signaling were reversed by PKA inhibitor, suggesting that cAMP/PKA is involved in the anti-inflammatory effects of imperatorin. In vivo studies of imiquimod- and interleukin-23-induced mouse psoriasiform dermatitis demonstrated that imperatorin alleviated skin desquamation, epidermal thickening, keratinocyte hyperproliferation, and neutrophil infiltration. Innovation and Conclusion: Our results demonstrate that imperatorin inhibits human neutrophil respiratory burst, adhesion, and migration through the elevation of cAMP/PKA to inhibit Akt, ERK, JNK, and Ca2+ mobilization. Imperatorin is a natural inhibitor of PDE4A/B/C and may serve as a lead for developing new therapeutics to treat neutrophilic psoriasis. Antioxid. Redox Signal. 35, 885-903.

Resveratrol suppresses neutrophil activation via inhibition of Src family kinases to attenuate lung injury.

The natural stilbenoid, Resveratrol (RSV; 3,5,4'-trihydroxystilbene) has been shown to have beneficial effects on inflammatory diseases as well as cancer, neurodegenerative diseases, and cardiovascular disorders. The underlying mechanism by which RSV affects neutrophil activation has yet to be fully elucidated. In this study, we tested the hypothesis that RSV modulates the inflammatory activities of formyl-Met-Leu-Phe-stimulated human neutrophils. We employed a well-established isolated-neutrophil model to investigate the effects of RSV on neutrophil functions and the underlying mechanism of signaling transduction. The lipopolysaccharide-induced ALI murine model was employed to evaluate the therapeutic effects of RSV. Experiment results demonstrate that RSV reduces respiratory burst, degranulation, integrin expression, and cell adhesion in activated neutrophils in dose-dependent manners. RSV inhibited phosphorylation of Src family kinases (SFKs) and reduced their enzymatic activities. Moreover, RSV and a selective inhibitor of SFKs (PP2) reduced the phosphorylation of Bruton's tyrosine kinase and Vav. There results indicated that the inhibitory effects of RSV are mediated through the inhibition of the SFKs-Btk-Vav pathway. This study also revealed that RSV attenuates endotoxin-induced lung injury. We surmise that the therapeutic effects of RSV on ALI may derive from its anti-neutrophilic inflammation function and free radical-scavenging effects.

Honokiol suppresses formyl peptide-induced human neutrophil activation by blocking formyl peptide receptor 1.

Formyl peptide receptor 1 (FPR1) mediates bacterial and mitochondrial N-formyl peptides-induced neutrophil activation. Therefore, FPR1 is an important therapeutic target for drugs to treat septic or sterile inflammatory diseases. Honokiol, a major bioactive compound of Magnoliaceae plants, possesses several anti-inflammatory activities. Here, we show that honokiol exhibits an inhibitory effect on FPR1 binding in human neutrophils. Honokiol inhibited superoxide anion generation, reactive oxygen species formation, and elastase release in bacterial or mitochondrial N-formyl peptides (FPR1 agonists)-activated human neutrophils. Adhesion of FPR1-induced human neutrophils to cerebral endothelial cells was also reduced by honokiol. The receptor-binding results revealed that honokiol repressed FPR1-specific ligand N-formyl-Nle-Leu-Phe-Nle-Tyr-Lys-fluorescein binding to FPR1 in human neutrophils, neutrophil-like THP-1 cells, and hFPR1-transfected HEK293 cells. However, honokiol did not inhibit FPR2-specific ligand binding to FPR2 in human neutrophils. Furthermore, honokiol inhibited FPR1 agonist-induced calcium mobilization as well as phosphorylation of p38 MAPK, ERK, and JNK in human neutrophils. In conclusion, our data demonstrate that honokiol may have therapeutic potential for treating FPR1-mediated inflammatory diseases.