baicalein and Inflammation

The flavonoids, baicalin (5,6-dihydroxy-2-phenyl-4H-1-benzopyran-4-one-7-O-d-β-glucuronic acid) 1 and its aglycone, baicalein 2 are found in edible medicinal plants, Scutellaria baicalensis Georgi and Oroxylum indicum (L.) Kurz in abundant quantities. The antioxidant and anti-inflammatory effects of these flavonoids have been demonstrated in various disease models, including diabetes, cardiovascular diseases, inflammatory bowel diseases, gout and rheumatoid arthritis, asthma, neurodegenerative-, liver- and kidney diseases, encephalomyelitis, and carcinogenesis. These flavonoids have almost no toxicity to human normal epithelial, peripheral and myeloid cells. Their antioxidant and anti-inflammatory activities are largely due to their abilities to scavenge the reactive oxygen species (ROS) and improvement of antioxidant status by attenuating the activity of NF-κB and suppressing the expression of several inflammatory cytokines and chemokines including monocyte chemotactic protein-1 (MCP-1), nitric oxide synthase, cyclooxygenases, lipoxygenases, cellular adhesion molecules, tumor necrosis factor and interleukins. In this review, we summarize the antioxidant and anti-inflammatory effects of baicalin and baicalein with molecular mechanisms for their chemopreventive and chemotherapeutic applications in the treatment of inflammatory-related diseases.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Flavanones; Flavonoids; Humans; Inflammation

The regulations of the NO and PGE(2) productions are research topics of interest in the field of anti-inflammatory drug development. In the present study, 5,6,7-trimethoxy- and 5,6,7-trihydroxyflavones 3a-3g were synthesized from cinnamic acid derivatives. In particular, 4'-bromo-5,6,7-trimethoxyflavone (3b) most potently inhibited the productions of NO and PGE(2) in LPS-treated RAW 264.7 cells (IC(50)=14.22 ± 1.25 and 10.98 ± 6.25 μM, respectively), and these inhibitory effects were more potent than those of oroxylin A or baicalein. Consistent with these findings, 3b concentration-dependently reduced the LPS-induced expressions of iNOS and COX-2 at the protein and mRNA levels. In addition, the release of TNF-α, IL-6, and IL-1β and the mRNA expressions of these cytokines were reduced by 3b in a concentration-dependent manner. Furthermore, 3b attenuated the LPS-induced transcriptional activities of NF-κB and this was accompanied by parallel reductions in the degradation and phosphorylation of IκB-α, and consequently by a decrease in the nuclear translocation of the p65 subunit of NF-κB. Taken together, these results suggest that suppressions of the expressions of iNOS, COX-2, TNF-α, IL-6, and IL-1β via NF-κB inactivation are responsible for the anti-inflammatory effects of 3b.

Topics: Animals; Anti-Inflammatory Agents; Cell Survival; Cyclooxygenase 2; Dose-Response Relationship, Drug; Drug Design; Flavones; Flavonoids; Inflammation; Inhibitory Concentration 50; Interleukin-1beta; Interleukin-6; Lipopolysaccharides; Macrophages; Mice; Models, Biological; Models, Chemical; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase Type II; RNA, Messenger; Signal Transduction; Tumor Necrosis Factor-alpha

The synthesis and characterization of 3-formylchromone (1) and its derivatives 2-24 and evaluation of their potential antiinflammatory activities is reported here. These compounds were characterized by (1)H NMR, EI MS, IR, and UV spectroscopic techniques and elemental analysis. The synthesized compounds were evaluated by using various in vitro and in vivo assay models for antiinflammatory activity and their effects were compared with known standard drug such as aspirin and indomethacin. Among all tested compounds, 1, 2, 5, 6, 9, 14, 16-19, 21-23, showed promising antiinflammatory activities. The results and SAR has been discussed in this report.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Carrageenan; Chromones; Cyclooxygenase Inhibitors; Edema; Female; Inflammation; Male; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Wistar; Respiratory Burst; Xanthine; Xanthine Oxidase

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