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Attenuation of acute lung injury in mice by oxymatrine is associated with inhibition of phosphorylated p38 mitogen-activated protein kinase

Abstract Oxymatrine is one of the alkaloids extracted from Chinese herb Sophora japonica (Sophora flavescens Ait.) with activities of anti-inflammation, inhibiting immune reaction, antivirus, protecting hepatocytes and antihepatic fibrosis. However, the effect of oxymatrine on acute lung injury (ALI) has not been known yet. In this study, the effect of oxymatrine on ALI was investigated using an oleic acid-induced ALI mouse model. Morphological findings showed that the oleic acid group demonstrated a marked lung injury represented by prominent atelectasis, intraalveolar and interstitial patchy hemorrhage, edema, thickened alveolar septum, formation of hyaline membranes and the existence of inflammatory cells in alveolar spaces. While in the oxymatrine/dexamethasone group, these changes were less severe and in the vicinity of the control group. Furthermore, pretreatment with oxymatrine significantly alleviated oleic acid-induced lung injury accompanied by reduction of lung index and wet-to-dry weight ratio, decreases in serum TNF-α level and inhibition of phosphorylated p38 MAPK. These findings suggest that oxymatrine has a beneficial effect on acute lung injury induced by oleic acid in mice and may inhibit the production of proinflammatory cytokine, TNF-α, by means of the inhibition of p38 MAPK.

Crocetin attenuates palmitate-induced insulin insensitivity and disordered tumor necrosis factor-α and adiponectin expression in rat adipocytes

A number of studies have implicated adipocyte‐derived factors in the development of insulin resistance. Intracellular redox status has been reported to play a significant role in the modulation of insulin action. This study was designed to investigate the potential of crocetin, a potent antioxidant, to protect adipocytes against the induction of insulin insensitivity and disordered expression of tumor necrosis factor (TNF)‐α and adiponectin in vitro.

Evidence of crocin against endothelial injury induced by hydrogen peroxide in vitro

Crocin, the digentiobiosyl ester of crocetin, was investigated for its cytoprotective effect on hydrogen peroxide-induced injury in bovine aortic endothelial cells (BAECs). The morphology of BAECs was observed by inverted phase contrast and electron microscopy. The MTT assay was used to measure cell viability. Cell apoptosis was evaluated by DNA argarose gel electrophoresis. The cells treated with H2O2 (200 μM) showed apoptotic changes as revealed by cell shrinkage, condensation of nuclei, membrane blebbing and formation of apoptotic body. A concentration-dependent inhibition of cell injury was seen in cultures treated with crocin at dosages ranging from 1 to 10 μM. Furthermore, in the H2O2-treated group, agarose gel electrophoresis displayed a “DNA ladder”. Whereas in the 10 μM crocin-pretreated group, cells remained intact and no “DNA ladder” was observed in agarose gel electrophoresis. Only very little DNA debris appeared on DNA-fragmentation analysis in the 1 μM crocin-pretreated group. Our data demonstrated that crocin has preventive effects on the cell apoptosis induced by H2O2, which may contribute to its utilisation for cardiovascular diseases (e.g., atherosclerosis and hypertension).

Anti-inflammatory effects and gastrointestinal safety of NNU-hdpa, a novel dual COX/5-LOX inhibitor.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with a risk of serious adverse events. Now, the development of dual inhibitors of cyclooxygenase (COX) and 5-lipoxygenase (5-LOX) has become a hot area in searching for safer NSAIDs. NNU-hdpa, 2-(4-hydroxylphenyl)-3-(3,5-dihydroxylphenyl) propenoic acid, a newly synthesized compound, is expected to have COX/5-LOX dual inhibition with an improved gastrointestinal profile. In this study, NNU-hdpa was subjected to in vitro and in vivo experiment protocols. In vitro COX/5-LOX inhibition assays showed that NNU-hdpa exhibits a dual inhibitory activity against the COX and 5-LOX enzymes. Anti-inflammatory activity in vivo was evaluated using two animal edema model tests. Pretreatment with NNU-hdpa (p.o.) dose-dependently inhibited the xylene-induced ear edema in mice and carrageenan-induced paw edema in rats respectively. In gastric lesion test, NNU-hdpa was gastric-sparing in that it elicited markedly fewer stomach lesions as compared to the stomach lesions caused by aspirin in rats. In further studies, NNU-hdpa was found to significantly inhibit the productions of PGE(2) and LTB(4) in LPS-challenged RAW 264.7, which is parallel to its prevention of the nuclear translocation of the NF-kappaB p50 and p65 subunits. These data indicate that NNU-hdpa comprises a novel class of dual inhibitors of COX and 5-LOX having therapeutic potential with an enhanced gastric safety profile.

Gu-4 Suppresses Affinity and Avidity Modulation of CD11b and Improves the Outcome of Mice with Endotoxemia and Sepsis

Background Systemic leukocyte activation and disseminated leukocyte adhesion will impair the microcirculation and cause severe decrements in tissue perfusion and organ function in the process of severe sepsis. Gu-4, a lactosyl derivative, could selectively target CD11b to exert therapeutic effect in a rat model of severe burn shock. Here, we addressed whether Gu-4 could render protective effects on septic animals. Methodology/Principal Findings On a murine model of endotoxemia induced by lipopolysaccharide (LPS), we found that the median effective dose (ED50) of Gu-4 was 0.929 mg/kg. In vivo treatment of Gu-4 after LPS challenge prominently attenuated LPS-induced lung injury and decreased lactic acid level in lung tissue. Using the ED50 of Gu-4, we also demonstrated that Gu-4 treatment significantly improved the survival rate of animals underwent sepsis induced by cecal ligation and puncture. By adhesion and transwell migration assays, we found that Gu-4 treatment inhibited the adhesion and transendothelial migration of LPS-stimulated THP-1 cells. By flow cytometry and microscopy, we demonstrated that Gu-4 treatment inhibited the exposure of active I-domain and the cluster formation of CD11b on the LPS-stimulated polymorphonuclear leukocytes. Western blot analyses further revealed that Gu-4 treatment markedly inhibited the activation of spleen tyrosine kinase in LPS-stimulated THP-1 cells. Conclusions/Significance Gu-4 improves the survival of mice underwent endotoxemia and sepsis, our in vitro investigations indicate that the possible underlying mechanism might involve the modulations of the affinity and avidity of CD11b on the leukocyte. Our findings shed light on the potential use of Gu-4, an interacting compound to CD11b, in the treatment of sepsis and septic shock.

Biological evaluation of 2-(4-amino-phenyl)-3-(3,5-dihydroxylphenyl) propenoic acid.

2-(4-Aminophenyl)-3-(3,5-dihydroxylphenyl) propenoic acid (CSN-07001) is a new compound based on the combination of resveratrol and propenoic acid derivatives. In vitro cyclooxygenase (COX)/5-lipoxygenase (5-LOX) inhibition assays showed that the test compound exhibited a dual inhibitory activity against the COX (COX-1 IC(50) = 2.20 microM, COX-2 IC(50) = 1.76 microM) and 5-LOX (IC(50) = 0.28 microM) enzymes. Further, the enhanced COX-1/COX-2/5-LOX expression in lipopolysaccaride-induced lung inflammation in mice was also suppressed by CSN-07001 in a concentration-dependent manner. In vivo studies showed that CSN-07001 exhibited potent anti-inflammatory and antinociceptive effects in different experimental models. We further examined the risk of gastric damage induced by CSN-07001. The test compound was gastric-sparing in that it elicited markedly fewer stomach lesions than indomethacin in rats. Taken together, our data indicate that CSN-07001 exhibits a novel class of dual inhibitors of COX and 5-LOX having therapeutic potential as non-steroidal anti-inflammatory agents with an enhanced gastric safety profile.