Oxide Production In Lipopolysaccharide-induced RAW Research Articles

Anti-inflammatory Coumarin and Benzocoumarin Derivatives from Murraya alata

Two new rare 8-methylbenzo[h]coumarins, muralatins A and B (1, 2), nine new C-8-substituted coumarins, muralatins C-K (3-11), and 22 known analogues (12-33) were isolated from the leaves of Murraya alata. The absolute configurations of compounds 5, 11, 23, 24, 27, 30, and 33 were assigned via comparison of their specific rotations, by Mosher's method, and by single-crystal X-ray diffraction and electronic circular dichroism (ECD) data of the in situ formed transition metal complexes. A putative biosynthesis pathway to 1 and 2 is proposed, and the chemical synthesis of 1 was accomplished through electrocyclization of 5,7-dimethoxy-8-[(Z)-3-methylbut-1,3-dienyl)]coumarin (12). Compounds 1, 2, 8, 12, and 31 showed inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values of 6.0-14.5 μM.

Inhibitory effects of oligochitosan on TNF-α, IL-1β and nitric oxide production in lipopolysaccharide-induced RAW264.7 cells.

Oligochitosan has been reported to possess anti-inflammatory properties; however, the mechanism of the antiinflammatory effects of oligochitosan remains unknown. The present study aimed to investigate the expression levels of inflammatory cytokines and the production of nitric oxide (NO), in the nuclear factor (NF)-κB pathway of lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophages. The results of the present study demonstrated that different concentrations of oligochitosan could significantly lower the levels of NO, tumor necrosis factor (TNF)-α and interleukin (IL)-1β, released from LPS-stimulated RAW264.7 cells. This was shown to be mediated through inhibiting the activation of the NF-κB pathway. These results demonstrate that oligochitosan may efficiently inhibit inflammation and has the potential to be an effective anti-inflammatory agent.

Anti-inflammatory Ursane- and Oleanane-Type Triterpenoids from Vitex negundo var. cannabifolia

Six new polyoxygenated triterpenoids, cannabifolins A-F (1-6), and eight known triterpenoids, 7-14, were isolated from the leaves of Vitex negundo var. cannabifolia. The absolute configuration of cannabifolin A (1) was determined by single-crystal X-ray crystallographic analysis. Compounds 1 and 2 represent a class of rare natural pentacyclic triterpenoids bearing cis-fused C/D rings and are the first examples of 12,19-epoxy ursane- and oleanane-type triterpenoids. Compounds 3, 7, 8, and 14 exhibited inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values in the range 24.9-40.5 μM.

Dihydrochalcones and homoisoflavanes from the red resin of Dracaena cochinchinensis (Chinese dragon's blood)

Two new dihydrochalcones, 4-hydroxy-2,4′-dimethoxydihydrochalcone (1) and 3,4′-dihydroxy-2,4,6-trimethoxydihydrochalcone (2), and a new homoisoflavane, 7,3′-dihydroxy-8,4′-dimethoxyhomoisoflavane (3), along with 12 known compounds (4–15), were isolated from the red resin of Dracaena cochinchinensis (Chinese dragon's blood). Their structures were assigned by a variety of spectroscopic techniques. Diversity of cleavage pathways were proposed for dihydrochalcones and homoisoflavanes based on the mass spectroscopic behaviors of those identified compounds using hybrid ion trap-time of flight mass spectrometry. All the compounds were evaluated for their inhibitory effects on nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages, and compound 9 exhibited mild inhibition of NO production in this assay with IC50 value of 50.3μM.

Anti-inflammatory lignanamides from the roots of Solanum melongena L.

Four new lignanamides, melongenamides A–D (1–4), together with six known ones (5–10), were isolated from the roots of Solanum melongena L. Their structures were elucidated on the basis of 1D and 2D NMR experiments and by comparison of their spectroscopic and physical data with the literature values. Compounds 2–8 exhibited inhibitions of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values ranging from 16.2 to 58.5μM.

Inhibitory effect of resveratrol dimerized derivatives on nitric oxide production in lipopolysaccharide-induced RAW 264.7 cells

Four types of resveratrol dimerized analogues were synthesized and evaluated in vitro on LPS-induced NO production in RAW 264.7 cells. The results showed that several compounds, especially those containing 1,2-diphenyl-2,3-dihydro-1H-indene core (type I), exhibited good inhibitory activities. Among 25 analogues, 12b showed a significant inhibitory activity (49% NO production at 10μM, IC50=3.38μM). Further study revealed that compound 12b could suppress LPS-induced iNOS expression, NO production, and IL-1β release in a concentration-dependently manner. The mechanism of action (MOA) involved for its anti-inflammatory responses was through signaling pathways of p38 MAPK and JNK1/2, but not ERK1/2.

Tetracyclic Diterpenoids with Isomerized Isospongian Skeleton and Labdane Diterpenoids from the Fruits of Amomum kravanh

Four novel diterpenoids, including three tetracyclic diterpenes with isomerized isospongian skeletons, kravanhins A-C (1-3), and kravanhin D (4), and three new labdane diterpenes (5-7) were isolated from the fruits of Amomum kravanh. Compounds 1-4 had unprecedented isospongian diterpene skeletons with a trans-anti-cis fused tricyclic ring system. The structures of compounds 1-7 were established on the basis of extensive analysis of NMR spectra, CD, and X-ray crystallography. Compound 2 showed inhibitory activity on nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophages with an IC(50) value of 36.2 μM.