Wogonin alleviates liver injury in sepsis through Nrf2-mediated NF-κB signalling suppression.

Sepsis is a life-threatening organ dysfunction syndrome, and liver is a susceptible target organ in sepsis, because the activation of inflammatory pathways contributes to septic liver injury. Oxidative stress has been documented to participate in septic liver injury, because it not only directly induces oxidative genotoxicity, but also exacerbates inflammatory pathways to potentiate damage of liver. Therefore, to ameliorate oxidative stress is promising for protecting liver in sepsis. Wogonin is the compound extracted from the medicinal plant Scutellaria baicalensis Geogi and was found to exert therapeutic effects in multiple inflammatory diseases via alleviation of oxidative stress. However, whether wogonin is able to mitigate septic liver injury remains unknown. Herein, we firstly proved that wogonin treatment could improve survival of mice with lipopolysaccharide (LPS)- or caecal ligation and puncture (CLP)-induced sepsis, together with restoration of reduced body temperature and respiratory rate, and suppression of several pro-inflammatory cytokines in circulation. Then, we found that wogonin effectively alleviated liver injury via potentiation of the anti-oxidative capacity. To be specific, wogonin activated Nrf2 thereby promoting expressions of anti-oxidative enzymes including NQO-1, GST, HO-1, SOD1 and SOD2 in hepatocytes. Moreover, wogonin-induced Nrf2 activation could suppress NF-κB-regulated up-regulation of pro-inflammatory cytokines. Ultimately, we provided in vivo evidence that wogonin activated Nrf2 signalling, potentiated anti-oxidative enzymes and inhibited NF-κB-regulated pro-inflammatory signalling. Taken together, this study demonstrates that wogonin can be the potential therapeutic agent for alleviating liver injury in sepsis by simultaneously ameliorating oxidative stress and inflammatory response through the activation of Nrf2.

Polymorphisms in genes of the de novo lipogenesis pathway and overall survival of hepatocellular carcinoma patients undergoing transarterial chemoembolization.

Aberrant expression of genes in de novo lipogenesis (DNL) pathway were associated with various cancers, including hepatocellular carcinoma (HCC). Single nucleotide polymorphisms (SNPs) of DNL genes have been reported to be associated with prognosis of some malignancies. However, the effects of SNPs in DNL genes on overall survival of HCC patients receiving transarterial chemoembolization (TACE) treatment are still unknown. In present study, nine SNPs in three genes (ACLY, ACACA and FASN) in DNL pathway were genotyped using the Sequenom iPLEX genotyping system in a hospital-based cohort with 419 HCC patients treated with TACE, and their associations with HCC overall survival were evaluated by Cox proportional hazard regression analysis under three genetic models (additive, dominant and recessive). Although we did not find any significant results in total analysis (all p>0.05), our stratified data showed that SNP rs9912300 in ACLY gene was significantly associated with overall survival of HCC patients with lower AFP level and SNP rs11871275 in ACACA gene was significantly associated with overall survival of HCC patients with higher AFP level. We further identified the significant interactions between AFP level and SNP rs9912300 or rs11871275 in the joint analysis. Conclusively, our data suggest that genetic variations in genes of DNL pathway may be a potential biomarker for predicting clinical outcome of HCC patients treated with TACE.

CD147 induces angiogenesis through a vascular endothelial growth factor and hypoxia-inducible transcription factor 1α-mediated pathway in rheumatoid arthritis.

OBJECTIVE: Rheumatoid arthritis (RA) is an inflammatory and angiogenic disease. However, the molecular mechanisms that promote angiogenesis in RA have not been clearly identified. Our objective was to study the role of CD147 in angiogenesis and determine whether the strategy in which CD147 is suppressed might be useful in reducing angiogenesis in RA. METHODS: Correlations among expression levels of CD147, vascular endothelial growth factor (VEGF), and hypoxia-inducible factor 1α (HIF-1α) were determined by immunohistochemistry staining. RA fibroblast-like synoviocytes (FLS) cells were cultured under various conditions, and the production of VEGF and HIF-1α was examined by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. The SCID mouse coimplantation model of RA (SCID-HuRAg) was established, mice were treated with CD147 monoclonal antibody, infliximab, or both CD147 and infliximab, and the volume of the grafts and the average vascular density were measured and analyzed. Western blot analyses were performed to examine the potential signaling pathways. RESULTS: The expression levels of CD147 showed significantly positive correlations with VEGF and HIF-1α levels, as well as with vascular density, in RA synovium. After small interfering RNA transfection or after addition of specific antibodies for CD147, the production of VEGF and HIF-1α were significantly reduced. The expression of VEGF and HIF-1α decreased more after CD147 inhibition than after infliximab treatment in the engrafted tissues in SCID-HuRAg mice. The phosphatidylinositol 3-kinase/Akt pathway may be involved in this process. CONCLUSION: CD147 induces up-regulation of VEGF and HIF-1α in RA FLS, further promotes angiogenesis, and leads to the persistence of synovitis. Inhibition of CD147 may be a promising target for novel therapeutic strategies.

Expression of CD147 (EMMPRIN) on neutrophils in rheumatoid arthritis enhances chemotaxis, matrix metalloproteinase production and invasiveness of synoviocytes.

The occurrence of neutrophils at the pannus-cartilage border is an important phenomenon for understanding the pathogenesis of rheumatoid arthritis (RA). Matrix metalloproteinases (MMPs) are predominant enzymes responsible for the cartilage degradation. The present article studied the expression of CD147 on neutrophils and its potential role in neutrophil chemotaxis, MMPs production and the invasiveness of fibroblast-like synoviocytes (FLS). The results of flow cytometry revealed that the mean fluorescence intensity of CD147 expression on neutrophils of peripheral blood from RA patients was higher than that in healthy individual. The potential role of CD147 in cyclophilin A (CyPA)-mediated cell migration was studied using chemotaxis assay and it was found that the addition of anti-CD147 antibody significantly decreased the chemotactic index of the neutrophils. Significantly elevated release and activation of MMPs were seen in the co-culture of neutrophil and FLS compared with cultures of the cells alone. An increased number of cells invading through the filters in the invasion assays were also observed in the co-cultured cells. The addition of anti-CD147 antibody had some inhibitory effect, not only on MMP production but also on cell invasion in the co-culture model. Our study demonstrates that the increased expression of CD147 on neutrophils in RA may be responsible for CyPA-mediated neutrophil migration into the joints, elevated MMPs secretion and cell invasion of synoviocytes, all of which may contribute to the cartilage invasion and bone destruction of RA. Better knowledge of these findings will hopefully provide a new insight into the pathogenesis of RA.

Annexin II promotes invasion and migration of human hepatocellular carcinoma cells in vitro via its interaction with HAb18G/CD147.

HAb18G/CD147, a member of the immunoglobulin family enriched on the surface of tumor cells, is reported to be correlated with invasion, metastasis, growth, and survival of malignant cells. Here, we found that annexin II, a 36-kDa Ca(2+)- and phospholipid-binding protein and in vivo substrate for tyrosine kinase and PKC, is a new interaction protein of HAb18G/CD147 in human hepatocellular carcinoma (HCC) cells. In the present study, we explored the unclear role of annxin II in HCC invasion and migration and the interaction effects between HAb18G/CD147 and annexin II. Our data show that downregulation of annexin II in HCC cells significantly decreased the secretion of MMP, migration ability, and invasive potential, and affected the cytoskeleton rearrangement of tumor cells. The MMP-2 level and invasive potential of HCC cells were regulated by both annexin II and HAb18G/CD147. Also, interaction effects exist between the two molecules in tumor progression, including MMP-2 production, migration, and invasion. These results suggest that annexin II promotes the invasion and migration of HCC cells in vitro, and annexin II and HAb18G/CD147 interact with each other in the same signal transduction pathway working as a functional complex in tumor progression.

The interaction of HAb18G/CD147 with integrin alpha6beta1 and its implications for the invasion potential of human hepatoma cells.

BACKGROUND: HAb18G/CD147 plays pivotal roles in invasion by hepatoma cells, but the underlying mechanism remains unclear. Our previous study demonstrated that overexpression of HAb18G/CD147 promotes invasion by interacting with integrin alpha3beta1. However, it has never been investigated whether alpha3beta1 is solely responsible for this process or if other integrin family members also interact with HAb18G/CD147 in human hepatoma cells. METHODS: Human SMMC-7721 and FHCC98 cells were cultured and transfected with siRNA fragments against HAb18G/CD147. The expression levels of HAb18G/CD147 and integrin alpha6beta1 were determined by immunofluorescent double-staining and confocal imaging analysis. Co-immunoprecipitation and Western blot analyses were performed to examine the native conformations of HAb18G/CD147 and integrin alpha6beta1. Invasion potential was evaluated with an invasion assay and gelatin zymography. RESULTS: We found that integrin alpha6beta1 co-localizes and interacts with HAb18G/CD147 in human hepatoma cells. The enhancing effects of HAb18G/CD147 on invasion capacity and secretion of matrix metalloproteinases (MMPs) were partially blocked by integrin alpha6beta1 antibodies (P < 0.01). Wortmannin, a specific phosphatidylinositol kinase (PI3K) inhibitor that reverses the effect of HAb18G/CD147 on the regulation of intracellular Ca2+ mobilization, significantly reduced cell invasion potential and secretion of MMPs in human hepatoma cells (P < 0.05). Importantly, no additive effect between Wortmannin and alpha6beta1 antibodies was observed, indicating that alpha6beta1 and PI3K transmit the signal in an upstream-downstream relationship. CONCLUSION: These results suggest that alpha6beta1 interacts with HAb18G/CD147 to mediate tumor invasion and metastatic processes through the PI3K pathway.

Silencing of calpain expression reduces the metastatic potential of human osteosarcoma cells.

Osteosarcoma, the most common primary bone tumor in young adults, is characterized by local invasion and distant metastasis. But detailed mechanisms of tumorigenicity and metastasis of osteosarcoma are not well known. We report the involvement of calpains, a family of calcium-activated, cysteine proteases, in the invasive and metastatic processes of human osteosarcoma cells. By using siRNA treatment, the expression of mu- and m-calpains were downregulated in human Saos-2 osteosarcoma cells. Both the adhesive and invasive potentials were significantly attenuated in calpain siRNA-transfected human Saos-2 osteosarcoma cells. MMPs are the main factors involved in malignant tumor invasion and metastasis. siRNA of calpains also significantly inhibited the secretion of MMP-2 in Saos-2 cells. These results suggest that mu- and m-calpains are important in the invasion and metastasis of human osteosarcoma cells, and calpains might be targeted to reduce tumor progression.