2--hydroxy-4-methoxychalcone and Inflammation

Inflammation is a major cause of skeletal muscle atrophy in various diseases. 2-Hydroxy-4'-methoxychalcone (AN07) is a chalcone-based peroxisome-proliferator-activated receptor gamma (PPARγ) agonist with various effects, such as antiatherosclerosis, anti-inflammation, antioxidative stress, and neuroprotection. In this study, we examined the effects of AN07 on protein homeostasis pathway and mitochondrial function in inflammation-associated myotube atrophy induced by lipopolysaccharides (LPS). We found that AN07 significantly attenuated NF-κB activation, inflammatory factors (TNF-α, IL-1β, COX-2, and PGE2), Nox4 expression, and reactive oxygen species levels in LPS-treated C2C12 myotubes. Moreover, AN07 increased SOD2 expression and improved mitochondrial function, including mitochondrial membrane potential and mitochondrial oxygen consumption rate. We also demonstrated that AN07 attenuated LPS-induced reduction of myotube diameter, MyHC expression, and IGF-1/IGF-1R/p-Akt-mediated protein synthesis signaling. Additionally, AN07 downregulated LPS-induced autophagy-lysosomal protein degradation molecules (LC3-II/LC3-I and degraded p62) and ubiquitin-proteasome protein degradation molecules (n-FoxO1a/MuRF1/atrogin-1). However, the regulatory effects of AN07 on protein synthesis and degradation signaling were inhibited by the IGF-1R inhibitor AG1024 and the PI3K inhibitor wortmannin. In addition, the PPARγ antagonist GW9662 attenuated the effects of AN07 against LPS-induced inflammation, oxidation, and protein catabolism. In conclusion, our findings suggest that AN07 possesses protective effects on inflammation-induced myotube atrophy and mitochondrial dysfunction.

Topics: Chalcone; Chalcones; Humans; Inflammation; Lipopolysaccharides; Muscle Fibers, Skeletal; Muscular Atrophy; Phosphatidylinositol 3-Kinases; PPAR gamma

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Arthritis; Cells, Cultured; Chalcones; Chronic Disease; Collagen; Dose-Response Relationship, Drug; Drug Development; Inflammation; Male; Mice; Mice, Inbred DBA; Molecular Structure; Nitric Oxide; RAW 264.7 Cells; Structure-Activity Relationship

Chalcone is a class of flavonoid compounds that are widely biosynthesized in plants. Epidemiological studies suggest that increased intake of flavonoids from fruits and vegetables reduces the risk of cardiovascular disease. However, the effect of chalcone on cardiovascular diseases has not been fully investigated. The aims of this study were to evaluate the antiatherosclerotic effect of 2-hydroxy-4'-methoxychalcone (AN07, a synthetic chalcone derivate) and to investigate its potential pharmacological mechanisms. Oxidized low-density lipoprotein (Ox-LDL) has been reported to stimulate proliferation of human aortic smooth muscle cells and that is one of the mechanisms resulting in atherosclerosis. In this study, we demonstrate that AN07 significantly inhibits the Ox-LDL-induced proliferation of human aortic smooth muscle cells. This effect is mediated via the inhibition of p44/42 mitogen-activated protein kinase and E-twenty six 1 phosphorylations. In the effect of anti-inflammation, AN07 decreases the Ox-LDL-stimulated upregulation of interleukin (IL) 1β and IL-6. In addition, AN07 acts synergistically with rosiglitazone and pioglitazone to inhibit the Ox-LDL-induced proliferation of human aortic smooth muscle cells and upregulation of cyclin D1, cyclin D3, IL-1β, and IL-6. These effects are a result of an increase in peroxisome proliferator-activated receptor gamma mRNA and protein expression stimulated by AN07 in human aortic smooth muscle cells. In conclusion, the chalcone derivate AN07 has versatile therapeutic potential against atherosclerosis by acting as peroxisome proliferator-activated receptor gamma inducer, p44/42 mitogen-activated protein kinase inhibitor, and cell cycle blocker.

Topics: Aorta; Atherosclerosis; Cell Cycle; Cell Proliferation; Chalcones; Drug Synergism; Gene Expression Regulation; Humans; Inflammation; Lipoproteins, LDL; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Pioglitazone; PPAR gamma; Rosiglitazone; Thiazolidinediones

This protocol describes microsphere-based protease assays for use in flow cytometry and high-throughput screening. This platform measures a loss of fluorescence from the surface of a microsphere due to the cleavage of an attached fluorescent protease substrate by a suitable protease enzyme. The assay format can be adapted to any site or protein-specific protease of interest and results can be measured in both real time and as endpoint fluorescence assays on a flow cytometer. Endpoint assays are easily adapted to microplate format for flow cytometry high-throughput analysis and inhibitor screening.

Topics: Animals; Biotinylation; Flow Cytometry; Fluorescence Resonance Energy Transfer; Green Fluorescent Proteins; High-Throughput Screening Assays; Humans; Inflammation; Kinetics; Microspheres; Peptide Hydrolases; Peptides; Reproducibility of Results; Temperature

A series of 2'-hydroxychalcones has been synthesized and screened for their in vitro inhibitory activities of cyclooxygenase-2 catalyzed prostaglandin production from lipopolysaccharide-treated RAW 264.7 cells. Structure-activity relationship study suggested that inhibitory activity against prostaglandin E(2) production was governed to a greater extent by the substituent on B ring of the chalcone, and most of the active compounds have at least two methoxy or benzyloxy groups on B ring. The relationship between chalcone structures and their PGE(2) inhibitory activities was also interpreted by docking study on cyclooxygenase-2.

Topics: Animals; Cell Line; Chalcone; Chalcones; Chemistry, Pharmaceutical; Cyclooxygenase 2; Dinoprostone; Drug Design; Inflammation; Inhibitory Concentration 50; Lipopolysaccharides; Mice; Models, Chemical; Structure-Activity Relationship; Time Factors