Dibenzylbutyrolactone lignans from Forsythia koreana fruits attenuate lipopolysaccharide-induced inducible nitric oxide synthetase and cyclooxygenase-2 expressions through activation of nuclear factor-κb and mitogen-activated protein kinase in RAW264.7 cells.

Previously, we reported that dibenzylbutyrolactone lignans (DBLLs) from the fruit of Forsythia koreana NAKAI (Oleaceae) has anti-inflammatory, antioxidant, and anti-asthmatic effects. In this study, to clarify the anti-inflammatory mechanisms of DBLL, we evaluated the effects of DBLLs on lipopolysaccharide-stimulated inducible nitric oxide synthetase (iNOS) and cyclooxygenase-2 (COX-2) expressions, nitric oxide (NO) and prostaglandin E(2) (PGE(2)) productions, nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) activations, inhibitor of κB (IκB) and inhibitor of κB kinase (IKK) phosphorylations in cytosolic proteins, and cytotoxicity in Raw264.7 cells. DBLLs potently suppressed both the enzyme expression and DNA-binding activity of NF-κB. Arctiin, arctigenin (1.0 µM) and matairesinol (10 µM) inhibited the expression of iNOS by 37.71±2.86%, 32.51±4.28%, and 27.44±2.65%, respectively, and arctiin, arctigenin (0.1 µM) and matairesinol (1.0 µM) inhibited COX-2 expression by 37.93±7.81%, 26.70±4.61% and 29.37±5.21%, respectively. The inhibitory effects of DBLLs on NO and PGE(2) productions were the same patterns as those seen for the reductions in iNOS and COX-2 expression, respectively. Arctiin, arctigenin (1.0 µM) and matairesinol (10 µM) significantly (p<0.05) inhibited NF-κB DNA binding by 44.85±6.67%, 44.16±6.61%, and 44.79±5.62%, respectively, and arctiin (0.1 µM) and arctigenin (1.0 µM) significantly (p<0.05) inhibited the phosphorylation of IκB by 20.58±3.86% and 25.99±6.18%, respectively. Furthermore, arctiin, matairesinol (1.0 µM) and arctigenin (10 µM) inhibited the phosphorylation of IKK by 38.80±6.64%, 38.33±6.65%, and 38.57±8.14%, respectively. In addition, DBLLs potently inhibited the lipopolysaccharide (LPS)-induced activation of MAPKs (SAPK/c-Jun NH(2)-terminal kinase (JNK), p38, and extracellular signal receptor-activated kinase (ERK)1/2). Overall, arctiin was the most effective; its effect was nearly the same as that of 10 µM helenalin. These findings suggest that treatment with non-toxic DBLLs inhibits not only NF-κB and NF-κB-regulated protein activation, but also potently inhibits the activations of specific MAPKs.

Effect of coenzyme Q10 on cutaneous healing in skin-incised mice.

Coenzyme Q10 (CoQ10) is a biosynthesized quinone with 10 isoprene side chains in humans. To investigate the anti-inflammatory and wound healing effect of CoQ10, we performed in vivo and in vitro experiments. In vivo studies, there were 3 groups; Naive (without skin incision), Control (with skin incision) and CoQ10 (100 mg/kg treatment with skin incision). Collagen-like polymer (CLP) level of CoQ10 group was increased significantly compared to the control group (p<0.05). Also, CoQ10 group showed significant inhibition on myeloperoxidase (MPO) and PLA(2) level compared to the control group (p<0.05). These data show that CoQ10 may have an anti-inflammatory and a wound healing effect. CoQ10 showed significant antioxidant activity in vivo on malondialdehyde (MDA) and superoxide dismutase (SOD) levels compared to the control group (p<0.05). Although CoQ10 did not show antioxidant activity in cell free system of DPPH radical scavenge, it had a potent antioxidant activity in cell culture system of both silica- and zymosan-induced reactive oxygen species generation using Raw 264.7 cells. This result may be associated with the conversion of CoQ10 to the reduced form (CoQ10H(2)) in the presence of some kinds of intracellular reducing agents. In conclusion, it is considered that CoQ10 appears to have a cutaneous healing effect in vivo, which may be related to the secondary action of CoQ10.

Flavonols attenuate the immediate and late-phase asthmatic responses to aerosolized-ovalbumin exposure in the conscious guinea pig.

We previously reported that quercetin and rutin have potent, anti-asthmatic activity, but the structure-activity relationships of flavonoids and anti-asthmatic agents are still poorly understood. In the current study, the effects of kaempferol, fisetin, and morin on the immediate-phase response (IAR) and late-phase response (LAR) caused by exposure to aerosolized-ovalbumin (OA) in OA-sensitized guinea pigs were evaluated by determining the specific airway resistance (sRaw), recruitment of leukocytes and chemical mediators in bronchoalveolar lavage fluid (BALF), histopathological surveys, and determination of neutrophil chemotaxis. Fisetin and kaempherol (30 mg/kg, p.o.) significantly (P<0.01) inhibited sRaw by 47.93% and 30.05% in IAR, and 54.45% and 40.50% in LAR, when compared to vehicle control, respectively. Furthermore, all three studied flavonols (30 mg/kg, p.o.) significantly (P<0.05) inhibited the recruitment of total, as well as subtypes of, leukocytes into the lung BALF. This recruitment inhibition corresponded to the inhibition of leukocyte infiltration, particularly of eosinophils and neutrophils, into the lung in pathological surveys and formly-methionyl-leucyl-phenylalanine (FMLP)-induced neutrophil chemotaxis studies. Kaempferol inhibited FMLP-induced neutrophil chemotaxis in a concentration-dependent manner in a tested range of 1-100 µM. Fisetin inhibited histamine content and peroxidase (EPO) activity in BALF in a dose-dependent manner. All three tested flavonols significantly (P<0.01) inhibited histamine content at 10 mg/kg, and phospholipase A(2) (PLA(2)) and EPO activities at 30 mg/kg (p.o.) in BALF. Kaempherol had a greater anti-asthmatic effect than other flavonols. Fisetin demonstrated the greatest inhibition of sRaw, whereas morin had lesser effects. These results indicate that the lower the molecular weight, the greater the anti-asthmatic activities of these compounds.

The analgesic and anti-inflammatory effects of 7-oxosandaracopimaric acid isolated from the roots of Aralia cordata.

The root of Aralia cordata is a traditional medicine for the treatment of inflammation, fever, pain, and spasm in the various diseases in Korea. We isolated a dibenzylbutyrolactone diterpene acid, 7-oxosandaracopimaric acid (OSA), from the ether fraction of Aralia cordata MeOH extract, and studied the effect of OSA on phenylquinone (PQ)-induced writhing syndrome and PQ-induced capillary permeability increase, compound 48/80-induced histamine release by peritoneal mast cells, cycloxygenase (COX) activities, and silica-induced RAW 264.7 cell reactive oxygen species production. OSA (30 mg/kg, p.o.) significantly (p < 0.05) inhibited PQ-induced writhes by 25.8% and the PQ-induced capillary permeability increase levels by 33.13% as compared with PQ control. Furthermore, OSA (10 mM) inhibited COX-1 by 22.82 +/- 1.94%, and COX-2 by 15.86 +/- 1.35%, respectively, to the same extent as indomethacin at the same concentration (10 mM). And OSA (3.0 mM) significantly (p < 0.05) inhibited compound 48/80-induced histamine release from rat mast cells, and its activity was similar to that of celebrex (1 mM), but no piracetam (0.1 mM) inhibited them. OSA did not inhibit ROS production in RAW 264.7 cells. These results indicated that OSA has analgesic and anti-inflammatory effects due to its inhibitory effects on capillary permeability, COX activities, and histamine release.

Antioxidant Effect of CoQ(10) on N-nitrosodiethylamine-induced Oxidative Stress in Mice.

The antioxidant effect of CoQ(10) on N-nitrosodiethylamine (NDEA)-induced oxidative stress was investigated in mice. Food intake and body weight were similar in both CoQ(10) and control groups during the 3-week experimental period. NDEA significantly increased the activities of typical marker enzymes of liver function (AST, ALT and ALP) both in control and CoQ(10) groups. However, the increase of plasma aminotransferase activity was significantly reduced in the CoQ(10) group. Lipid peroxidation in various tissues, such as heart, lung, liver, kidney, spleen and plasma, was significantly increased by NDEA, but this increase was significantly reduced by 100 mg/kg of CoQ(10). Superoxide dismutase activity increased significantly upon NDEA-induced oxidative stress in both the control and CoQ(10) groups with the effect being less in the CoQ(10) group. Catalase activity decreased significantly in both the control and CoQ(10) groups treated with NDEA, again with the effect being less in the CoQ(10) group. The lesser effect on superoxide dismutase and catalase in the NDEA-treated CoQ(10) group is indicative of the protective effect CoQ(10). Thus, CoQ(10) can offer useful protection against NDEA-induced oxidative stress.