Mechanisms in mediating the anti-inflammatory effects of baicalin and baicalein in human leukocytes

To evaluate the possible mechanisms responsible for the anti-inflammatory effects of baicalin or baicalein, phorbol-12-myristate-13-acetate (PMA)- or N-formyl-methionyl-leucyl-phenylalanine (fMLP)-activated inflammatory responses of peripheral human leukocytes were studied. Both baicalin and baicalein diminished fMLP- or PMA-induced reactive oxygen intermediates production in neutrophils or monocytes. Neither baicalin nor baicalein prevented the protein kinase C (PKC)-dependent assembly of the NADPH oxidase. Conversely, myeloperoxidase (MPO) activity was inhibited by baicalin or baicalein. fMLP-induced activation of leukocytes, as reflected by increased surface expression of Mac-1 (CD11b/CD18) and Mac-1-dependent neutrophil adhesion, were also inhibited by baicalin or baicalein. Furthermore, baicalein, but not baicalin, impeded fMLP- or AlF(4)(-)-induced Ca(2+) influx. We conclude that impairment of reactive oxygen intermediates production, through scavenging reactive oxygen intermediates by baicalin, or antagonizing ligand-initiated Ca(2+) influx by baicalein, accounts for the inhibition of Mac-1-dependent leukocyte adhesion that confers the anti-inflammatory activity of baicalin or baicalein.     

A novel NO-production-inhibiting triterpene and cytotoxicity of known alkaloids from Euonymus laxiflorus

A new triterpene, laxifolone A (1), four known sesquiterpene alkaloids, ebenifoline E-II (2), carigorinine E (3), euojaponine C (4), and emarginatine E (5), and six triterpenoids, 3-hydroxyolean-12-en-22,29-gamma-lactone, 3,11-dioxo-beta-amyrene, 3beta,22alpha-dihydroxyolean-12-en-29-oic acid, 28,29-dihydroxyfriedelan-3-one, 29-hydroxy-3-oxo-D:A-friedooleanan-28-oic acid, and putranjivadione, were isolated from the stems and leaves of Euonymus laxiflorus. Structural elucidations of these compounds were established by spectral analysis. Compound 1 displayed significant nitric oxide (NO) inhibitory effect.     

Phenylpropanoid glycosides from Orobanche caerulescens

Two new phenylpropanoid glycosides, caerulescenoside ( 1), and 3'-methyl crenatoside ( 2), as well as five known phenylpropanoid glycosides [acteoside ( 3), isoacteoside ( 4), campneoside II ( 5), crenatoside ( 6), and desrhamnosyl acteoside ( 7)] were isolated from the whole plant of Orobanche caerulescens. The antioxidative effects of compounds 1 - 7 on human low-density lipoprotein were evaluated. All these compounds suppress concentration-dependently conjugated diene formation with IC (50) values of 1.25 +/- 0.06, 2.97 +/- 0.31, 0.31 +/- 0.01, 1.01 +/- 0.05, 1.15 +/- 0.04, 1.69 +/- 0.15, and 0.64 +/- 0.03 microM, respectively. Comparison of their antioxidative activities with that of resveratrol (IC (50) : 6.75 +/- 1.05 microM), a natural phenolic antioxidant isolated from grape, demonstrated that the prolonged effect on lag-time and the damping effect on oxidative rate by compounds 1 - 7 were all more potent.     

FGF-21 Plays a Crucial Role in the Glucose Uptake of Activated Monocytes

Monocytes display a gradual change in metabolism during inflammation. When activated, the increase in glucose utilization is important for monocytes to participate in immune and inflammatory responses. Further studies on the mechanism underlying this biological phenomenon may provide a new understanding of the relationship between immune response and metabolism. The THP-1 cells were used as a monocyte model. The cells were activated with lipopolysaccharide (LPS). Glucose uptake was measured using flow cytometry. The expression of fibroblast growth factor 21 (FGF-21), glucose transporter 1 (GLUT-1), and other FGF-21 signaling pathway-related factor mRNAs was determined by real-time polymerase chain reaction. Further, the relationship between FGF-21 expression in monocytes and phosphatidylinositol-3-kinase (PI3K)-protein kinase B (Akt) signaling pathway was determined by Western blotting. LPS elevated FGF-21 expression in monocytic THP-1 cells in vitro. Functional assays showed that the phenomenon in which LPS and FGF-21 stimulated glucose uptake in monocytic THP-1 cells could be inhibited by FGFR inhibitor. The mechanism of elevation of FGF-21 was found to involve the PI3K/Akt signaling pathway. This study indicated that FGF-21 could regulate the immune response indirectly by influencing the glucose uptake of activated monocytes cells.     

Prognostic value of parapharyngeal extension in nasopharyngeal carcinoma treated with intensity modulated radiotherapy

Background and purpose

The development of improved diagnostic and therapeutic techniques has revolutionized the management of nasopharyngeal carcinoma (NPC). The purpose of this study is to revaluate the prognostic value of parapharyngeal extension in NPC in the IMRT era.

Material and methods

We retrospectively reviewed data from 749 biopsy-proven non-metastatic NPC patients. All patients were examined with magnetic resonance imaging (MRI) and received intensity-modulated radiotherapy (IMRT) as the primary treatment.

Results

The incidence of parapharyngeal extension was 72.1%. A significant difference was observed in the disease-free survival (DFS; 70.3% vs. 89.1%, P < 0.001), distant metastasis-free survival (DMFS; 79.3% vs. 92.0%, P < 0.001), and local relapse-free survival (LRFS; 92.8% vs. 99.0%, P = 0.002) of patients with and without parapharyngeal extension. Parapharyngeal extension was an independent prognostic factor for DFS and DMFS in multivariate analysis (P = 0.001 and P = 0.015, respectively), but not LRFS. The difference between DMFS in patients with or without parapharyngeal space extension was statistically significant in patients with cervical lymph node metastasis (P < 0.001).

Conclusions

In the IMRT era, parapharyngeal extension remains a poor prognosticator for DMFS in NPC, especially in patients with positive lymph node metastasis. Additional therapeutic improvements are required to achieve a favorable distant control in NPC with parapharyngeal extension.     

盐酸多柔比星脂质体注射液中磷脂膜成分的HPLC-ELSD测定

建立了HPLC-ELSD法测定盐酸多柔比星脂质体注射液磷脂膜中胆固醇、磷脂酰胆碱和溶血磷脂酰胆碱的含量,采用氨基色谱柱,流动相为2%草酸-乙醇-甲醇-氯仿(16:84:97:3),流速1ml/min.三者的平均回收率分别为98.8%、98.7%、98.6%,RSD为1.3%、0.9%、1.4%.     

筛选糖尿病候选药物FGF-21受体激动剂的新型细胞模型的建立

建立以成纤维细胞生长因子-21(fibroblast growth factor-21,FGF-21)信号通路为靶点的药物筛选细胞模型,用于筛选FGF-21受体激动剂类的新型治疗糖尿病药物。FGF-21的生理功能主要是通过细胞表面的FGFR及辅助受体βklotho传递信号,从而激活细胞内相关调控的一系列信号通路以及基因转录来实现的。本实验将βklotho基因构建到逆转录病毒表达载体pBMN-IRES-EGFP。将该载体导入包装细胞,收集病毒上清液并感染3T3-L1细胞,筛选到稳定表达βklotho细胞系。该细胞模型在FGF-21作用下可以促进细胞葡萄糖转运蛋白-1表达及转运水平升高,从而提高细胞糖吸收能力。构建该细胞系可以方便对FGF-21及类似药物进行高通量筛选,为糖尿病药物的研究提供了一种新方法。     

1,3,5-trihydroxy-4-prenylxanthone represses lipopolysaccharide-induced iNOS expression via impeding posttranslational modification of IRAK-1

Both high level of nitric oxide (NO) and its generating enzyme, inducible NO synthase (iNOS), play important roles in pathophysiological conditions such as inflammatory processes. We previously found that 1,3,5-trihydroxy-4-prenylxanthone (TH-4-PX) isolated from Cudrania cochinchinensis repressed lipopolysaccharide (LPS)-induced NO production in RAW264.7 macrophages. Here we further examined the underlying mechanisms using RT-PCR and Western blot analyses. Consistent with NO inhibition, suppression of LPS-induced iNOS expression by TH-4-PX through abolishing IκB kinase (IKK) phosphorylation, IκB degradation and nuclear factor-κB (NF-κB) nuclear translocation was observed. After LPS stimulation, the increased nuclear level of c-Fos and c-Jun (major components of activator protein-1, AP-1) and the phosphorylated level of upstream signal molecules, such as c-Jun NH2-terminal kinase (JNK) and extracellular signal-regulated kinase, (ERK) were all significantly suppressed by TH-4-PX, while p38 remained unaffected. A further experiment revealed that TH-4-PX inhibited the phosphorylation of transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1), an upstream signaling molecule required for IKK and mitogen-activated protein kinases (MAPKs) activation. Stimulation with LPS also triggered the modification (phosphorylation and ubiquitination) and eventually the proteasomal degradation of membrane-associated interleukin (IL)-1 receptor-associated serine/threonine kinase 1 (IRAK-1), an essential signaling component to toll-like receptor (TLR)-mediated TAK-1 activation. Interestingly, the modified pattern of IRAK-1 in the presence LPS was significantly attenuated by TH-4-PX treatment. In conclusion, TH-4-PX inhibited LPS-induced NF-κB and AP-1 activations by interfering with the posttranslational modification (phosphorylation and/or ubiquitinylation) of IRAK-1 in the cell membrane to impede TAK1-mediated activation of IKK and MAPKs signal transduction.