Docosahexaenoic Acid Inhibits Tumor Promoter-Induced Urokinase-Type Plasminogen Activator Receptor by Suppressing PKCδ- and MAPKs-Mediated Pathways in ECV304 Human Endothelial Cells

Diagnosis of sepsis with inflammatory biomarkers, cytokines, endothelial functional markers from SIRS patients

BACKGROUND

Sepsis is a life-threatening illness with a challenging diagnosis. Rapid detection is the key to successful treatment of sepsis. To investigate diagnostic value, the plasma protein profiles of inflammatory biomarkers, cytokines, and endothelial functional markers were compared between healthy controls, SIRS, and septic patients.

METHODS

The plasma protein profiles were performed by Luminex Assay in a cohort of 50 SIRS patients, 82 septic patients and 25 healthy controls. Fourteen plasma proteins were analyzed in the same cohort: IL-1β, IL-6, IL-8, IL-10, CCL-2, VEGF, VEGF-C, VEGFR2, CD62E, CD62P, MFG-E8, ICAM-1, TFPI, Urokinase.

RESULT

IL-2R, IL-6, IL-8, IL-10, CCL-2, ICAM-1, and Urokinase were significantly higher in sepsis patients than SIRS patients. VEGF, IL-1β, CD62E, CD62P, MFG-E8, and TFPI have no statistical difference. VEGF-C, VEGFR2 were significantly different in SIRS patients than sepsis patients. Urokinase, ICAM-1, and VEGFR2 were significantly different between sepsis group and SIRS group. The AUCs of Urokinase, ICAM-1, and VEGFR2 and the combination for the diagnosis of sepsis were 0.650, 0.688, 0.643, and 0.741, respectively.

CONCLUSIONS

Most patients have the higher level of several cytokines and developed endothelial cell injury in the initial phase of sepsis, Urokinase, ICAM-1, and VEGFR2 may be useful to evaluate severity and prognosis of sepsis patients.

Suppression of Urokinase-Type Plasminogen Activator Receptor by Docosahexaenoic Acid Mediated by Heme Oxygenase-1 in 12-O-Tetradecanoylphorbol-13-Acetate-Induced Human Endothelial Cells

Urokinase-type plasminogen activator receptor (uPAR) plays a crucial role in inflammation and tumor metastasis. Docosahexaenoic acid (DHA), a representative omega-3 polyunsaturated fatty acid, has been shown to exhibit anti-inflammatory and anti-tumor properties. However, the mechanism by which DHA negatively regulates uPAR expression is not yet understood. The aim of this study was to investigate the effect of DHA on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced uPAR expression and potential role of heme oxygenase-1 (HO-1) in DHA-induced inhibition of uPAR in human endothelial ECV304 cells. Results showed that TPA induced uPAR expression in a time dependent manner, while DHA inhibited uPAR expression in a concentration-dependent manner. Moreover, treatment with DHA induced HO-1 expression in a time- and concentration-dependent manner. In addition, DHA-induced inhibition of uPAR expression and cell invasion in TPA-stimulated cells was reversed by si-HO-1 RNA. Induction of HO-1 by ferric protoporphyrin IX (FePP) inhibited TPA-induced uPAR expression, and this effect was abolished by treatment with the HO-1 inhibitor tin protoporphyrin IX (SnPP). Additionally, carbon monoxide, an HO-1 product, attenuated TPA-induced uPAR expression and cell invasion. Collectively, these data suggest a novel role of DHA-induced HO-1 in reducing uPAR expression and cell invasion in human endothelial ECV304 cells.

Urokinase-type plasminogen activator protects human umbilical vein endothelial cells from apoptosis in sepsis

The aim of this study was to investigate the effect of urokinase-type plasminogen activator (uPA) on cell viability, apoptosis, and inflammatory cytokine levels in septic human umbilical vein endothelial cells (HUVECs). Lipopolysaccharides (LPS) were added to construct septic HUVECs, then the septic HUVECs were treated by uPA, and cell viability, apoptosis, TNF-α, IL-6, GMCSF and uPAR levels were evaluated by CCK-8, AV/PI, qPCR, western blot and ELISA, respectively. Subsequently, uPA shRNA was transferred into septic HUVECs, and the cells viability, cell apoptosis and the expressions of TNF-α, IL-6, GMCSF, as well as uPAR were assessed by the same methods. uPA promoted viability while reducingapoptosis in septic HUVECs. However, uPA had no effect on the regulation of TNF-α or IL-6 expression in septic HUVECs. In addition, uPA elevated the expressions of GMCSF and uPAR in septic HUVECs. After the transfection of uPA shRNA, cell viability was decreased, apoptosis was enhanced, and GMCSF and uPAR expressions were reduced, while TNF-α or IL-6 expression did not vary in septic HUVECs. In conclusion, uPA promotes cell viability, represses apoptosis,and has no effect on regulating inflammatory cytokines in septic HUVECs.

Andrographolide Antagonizes TNF-α-Induced IL-8 via Inhibition of NADPH Oxidase/ROS/NF-κB and Src/MAPKs/AP-1 Axis in Human Colorectal Cancer HCT116 Cells

Andrographis paniculata Nees is used as a functional food in Japan, Korea, India, and China. Andrographolide, a naturally occurring phytochemical identified in Andrographis paniculata, has been discovered to present anti-inflammatory and anticancer activities. Highly expressed interleukin (IL-8) has been detected in colorectal cancer and is implicated in angiogenesis. However, the effect and molecular mechanisms of IL-8 expression by andrographolide remain obscure in human colorectal cancer cells. The present study was aimed to investigate the effects of andrographolide on TNF-α-induced IL-8 expression and its underlying mechanisms. We found that andrographolide concentration-dependently inhibited TNF-α-induced IL-8 mRNA (2.23 ± 0.15 fold at 20 μM) and protein expression (4.78 ± 0.31 fold at 20 μM) and reduced the IL-8 transcriptional activity (2.59 ± 0.25 fold at 20 μM). TNF-α stimulated the membrane translocation of p47^phox to activate reactive oxygen species (ROS)-producing NADPH oxidase (NOX). Furthermore, TNF-α induced Src and MAPKs (Erk1/2, p38 MAPK) phosphorylation, as well as NF-κB and AP-1 binding activities. We found that NF-κB and AP-1 were the critical transcription factors for TNF-α-induced IL-8 expression. Specific inhibitors and mutagenesis studies indicated that Src, Erk1/2, and p38 MAPK are related to TNF-α-induced IL-8. NOX-derived ROS and Src/MAPKs (Erk1/2 and p38 MAPK) functioned as upstream activators of NF-κB and AP-1, respectively. Taken together, andrographolide antagonizes TNF-α-induced IL-8 via inhibition of NADPH oxidase/ROS/NF-κB and Src/MAPKs/AP-1 signaling pathways in HCT116 colorectal cancer cells and then suppresses angiogenesis in the tumor microenvironment.

Docosahexaenoic Acid Inhibits Cerulein-Induced Acute Pancreatitis in Rats

Oxidative stress is an important regulator in the pathogenesis of acute pancreatitis (AP). Reactive oxygen species induce activation of inflammatory cascades, inflammatory cell recruitment, and tissue damage. NF-κB regulates inflammatory cytokine gene expression, which induces an acute, edematous form of pancreatitis. Protein kinase C δ (PKCδ) activates NF-κB as shown in a mouse model of cerulein-induced AP. Docosahexaenoic acid (DHA), an ω-3 fatty acid, exerts anti-inflammatory and antioxidant effects in various cells and tissues. This study investigated whether DHA inhibits cerulein-induced AP in rats by assessing pancreatic edema, myeloperoxidase activity, levels of lipid peroxide and IL-6, activation of NF-κB and PKCδ, and by histologic observation. AP was induced by intraperitoneal injection (i.p.) of cerulein (50 μg/kg) every hour for 7 h. DHA (13 mg/kg) was administered i.p. for three days before AP induction. Pretreatment with DHA reduced cerulein-induced activation of NF-κB, PKCδ, and IL-6 in pancreatic tissues of rats. DHA suppressed pancreatic edema and decreased the abundance of lipid peroxide, myeloperoxidase activity, and inflammatory cell infiltration into the pancreatic tissues of cerulein-stimulated rats. Therefore, DHA may help prevent the development of pancreatitis by suppressing the activation of NF-κB and PKCδ, expression of IL-6, and oxidative damage to the pancreas.