Rosiglitazone alleviates lipopolysaccharide-induced inflammation in RAW264.7 cells via inhibition of NF-κB and in a PPARγ-dependent manner.

Rosiglitazone is a synthetic peroxisome proliferator-activated receptor (PPAR)γ agonist widely used for the treatment of type 2 diabetes. Recent studies have demonstrated that rosiglitazone displays anti-inflammatory effects. The present study aimed to investigate whether rosiglitazone alleviates decreases in RAW264.7 cell viability resulting from lipopolysaccharide (LPS)-induced inflammation, as well as exploring the underlying mechanism. A macrophage inflammatory injury model was established by treating RAW264.7 cells with 100 ng/ml LPS. Cells were divided into LPS and rosiglitazone groups with different concentrations. Cell viability was assessed by performing an MTT assay. The expression of inflammatory cytokines was detected by conducting enzyme-linked immunosorbent assays and reverse transcription-quantitative PCR. Nitric oxidesecretion was assessed using the Griess reagent system. The expression levels of key nuclear factor-κB pathway-associated proteins were detected via western blotting. Rosiglitazone alleviated LPS-induced decrease in RAW264.7 cell viability and inhibited inflammatory cytokine expression in a concentration-dependent manner. Rosiglitazone significantly inhibited LPS-induced upregulation of p65 phosphorylation levels and downregulated IκBα expression levels. However, rosiglitazone-mediated inhibitory effects were reversed by PPARγ knockdown. The results of the present study demonstrated that rosiglitazone significantly inhibited LPS-induced inflammatory responses in RAW264.7 macrophage cells, which was dependent on PPARγ activation and NF-κB suppression.

Association between TNF-α G-308A (rs1800629) polymorphism and susceptibility to chronic periodontitis and type 2 diabetes mellitus: A meta-analysis.

BACKGROUND AND OBJECTIVE: Although the association between tumor necrosis factor-α (TNF-α) G-308A (rs1800629) polymorphism and chronic periodontitis (CP), chronic periodontitis with type 2 diabetes mellitus (DP) is assumed, results of this association have been contradictory. The aim of this study was to assess the relationship between rs1800629 polymorphism and CP/DP susceptibility. METHODS: We searched for studies on PubMed, Web of Science, MEDLINE, Chinese National Infrastructure, and WanFang databases. Study selection was performed using specific inclusion and exclusion criteria and fulfilled the PECO (participant, exposure, comparison, and outcome) format. The relationship between rs1800629 polymorphism and CP/DP susceptibility was evaluated by the effect summary odds ratio (OR) and 95% confidence intervals (CIs). Allele, dominant, and recessive genetic models were computed to assess the strength of the association. RESULTS: A total of 25 case-control studies were included in the analysis. In the Asian population, TNF-α rs1800629 polymorphism was found to be significantly associated with CP in the overall analyses and for all genetic contrasts, while no significant risks were found among Caucasian populations for all genetic contrasts. The TNF-α rs1800629 polymorphism was also associated with increased DP risk in Asians under the fixed-effects model, but not in the recessive comparison. CONCLUSION: The meta-analysis suggested that TNF-α rs1800629 polymorphism might affect the risk of CP and DP, particularly in individuals of Asian descent.

Obesity-Induced Upregulation of ZBTB7A Promotes Lipid Accumulation through SREBP1.

OBJECTIVE: Nonalcoholic fatty liver disease (NAFLD) is among the most common chronic liver diseases. However, the pathogenesis of NAFLD is not still unclear. This study aims at evaluating the role of zinc finger and BTB domain-containing 7A (ZBTB7A) in NAFLD. METHODS: Western blotting, real-time reverse transcription PCR (RT-PCR), and immunohistochemistry were submitted to evaluate the level of ZBTB7A in the high fatty diet- (HFD-) induced NAFLD mouse model. In vitro, the expression of ZBTB7A was assessed in oleic acid- (OA-) induced HepG2 cells with western blotting and RT-PCR. The luciferase reporter assay was used to estimate the effect of ZBTB7A on the SREBP1 and NF-κB, and the ChIP assay was subjected to evaluate the direct binding to the SREBP1 promoter. Oil Red staining was used to detect lipid accumulation, and the ELISA was used to verify the levels of TG, T-CHO, and MDA. ZBTB7A was knocked down with siRNA, and RT-PCR was performed to analyze the lipogenesis-, fatty acid transporter-, and oxidation metabolism-related genes expression. The levels of ZBTB7A in primary hepatocyte, Kupffer, and hepatic stellate cells (HSCs) were tested by RT-PCR. RESULTS: The upregulation of ZBTB7A expression was assessed in NAFLD mice, and ZBTB7A expression was positively correlated with TNFα, IL-6, TG, T-CHO, and MDA. ZBTB7A was highly expressed in the hepatocytes. In vitro, OA-induced ZBTB7A expression and ZBTB7A expression were closely associated with SREBP1c. ZBTB7A could activate the promoter activity of SREBP1 and activate NF-κB activity. Interestingly, the direct binding of ZBTB7A in the SREBP1 promoter was acquired in HepG2 cells. Inhibition of ZBTB7A expression could attenuate OA-induced lipid accumulation, inhibit the expression of the lipogenesis-related genes and fatty acid transporter genes, and promote the expression of oxidation metabolism-related genes. CONCLUSION: ZBTB7A plays a significant role in the development process of NAFLD, and obesity-induced upregulation of ZBTB7A promotes lipid accumulation through activation of SREBP1 and NF-κB. ZBTB7A may be a potential novel target for the therapy of NAFLD.

The role of MAPK signaling pathway in formation of EMT in oral squamous carcinoma cells induced by TNF-α.

To study the role of MAPK signaling pathway in the development of Epithelial-mesenchymal transition in oral squamous cell carcinoma induced by inflammatory factor TNF-α. After the action of TNF-α, the expression of JNK, ERK, P38 in MAPK signaling pathway increased and the expression of E-cadherin, Claudin1 decreased significantly compared to the normal control group. After the addition of corresponding inhibitor, the expression of JNK, ERK, P38 decreased and the expression of E-cadherin, Claudin1 increased compared with TNF-α group. TNF-α regulated the role of EMT in promoting the invasion and metastasis of oral squamous carcinoma cells through MAPK signaling pathway.

Snail interacts with Id2 in the regulation of TNF-α-induced cancer cell invasion and migration in OSCC.

The inflammatory tumor microenvironment has been identified to play a pivotal role in tumor development and metastasis. Tumor necrosis factor-α (TNF-α) is one of the key cytokines that regulate the inflammatory processes in tumor promotion. In the current study, we treated three oral squamous cell carcinoma (OSCC) cell lines with TNF-α to study its role in inflammation-induced tumor progression. Here we show that TNF-α induces stabilization of the transcriptional repressor Snail and activates NF-κB pathway in the three OSCC cell lines. These activities resulted in the increased motility and invasiveness of three OSCC cell lines. In addition, upon dealing with TNF-α for the indicated time, three OSCC cell lines underwent epithelial-to-mesenchymal transition (EMT), in which they presented a fibroblast-like phenotype and had a decreased expression of epithelial marker (E-cadherin) and an increased expression of mesenchymal marker (vimentin). We further demonstrated that TNF-α can up-regulate the expression of Id2 while inducing an EMT in oral cancer cells. Finally, we showed that Id2 interacted with Snail which may constrain Snail-dependent suppression of E-cadherin. In conclusion, our study indicates that TNF-α induces Snail stabilization is dependent on the activation of NF-κB pathway and results in increasing cell invasion and migration in OSCC cells. Id2 may contribute to regulate the function of Snail during TNF-α-mediated EMT in OSCC. These findings have significant implications for inflammation-induced tumor promotion in OSCC.

Zinc dependent endopeptidases of matrix metalloproteinases-9 expressions is associated with tumor metastases of oral squamous cell carcinoma in Chinese population: a meta-analysis.

Matrix metalloproteinase-9 (MMP-9) is an important member of zinc dependent endopeptidases family and is considered to be involved in the invasion and metastasis of cancer cells. Many studies were published to assess the prognostic role of MMP-9 expression in patients with oral squamous cell Carcinoma, but the findings from those studies were inconsistent in Chinese population. We searched eligible studies in Pubmed, Embase, and Web of Science databases. Six studies with a total of 556 patients were finally included into the meta-analysis. The pooled odds ratios (OR) with the corresponding 95% confidence interval (95% CIs) for positive rate of MMP-9 were calculated by using meta-analysis. Overall, MMP-9 positive expression was associated with tumor metastases in patients with oral squamous cell Carcinoma (fixed-effects OR 4.24, 95% CI 2.25-7.99, P < 0.001; random-effects OR 4.35, 95% CI 2.31-8.21, P < 0.001). Our results indicated that MMP-9 expression is associated with tumor metastases in patients with oral squamous cell carcinoma, and patients with higher MMP-9 expression have less tumor metastases.

Inhibitory effect of ARHI on pancreatic cancer cells and NF-κB activity.

The aim of this study was to investigate the effect of aplasia ras homolog member I (ARHI) on proliferation, apoptosis and the cell cycle in the pancreatic cancer cell line PANC-1. The study also aimed to examine the effect of ARHI on the activity of the nuclear factor (NF)-κB and to determine whether ARHI acts as a tumor suppressor in the development of pancreatic cancer by inhibiting the activity of NF-κB. A pIRES2­EGFP­ARHI vector, constructed by reverse transcrition (RT)­PCR, was transiently transfected into the PANC-1 cells and analyzed for the expression of the ARHI protein by western blotting. A MTT assay was used to quantify cell proliferation, and apoptosis was analyzed by flow cytometry. The NF­κB signaling pathway, specifically the pathway using the nuclear phosphorylated p65 isoform, was analyzed by western blotting. Expression of the ARHI protein was detected by western blotting subsequent to the PANC-1 cells being transiently transfected with the pIRES2­EGFP­ARHI construct. Cell proliferation was strongly inhibited in the PANC-1 cells transfected with pIRES2­EGFP­ARHI. The cell cycle assays indicated an increase in the number of cells at the G0/G1 phase and a decrease in the cells at the S phase, but the difference was not significant (P>0.05). Time course studies also indicated a marked increase in the apoptotic index following transient transfection, as well as a gradual decrease in the expression of the nuclear phosphorylated p65 protein. ARHI acts as a tumor suppressor by downregulating the NF­κB signaling pathway, which results in the inhibition of cell proliferation, apoptosis and the cell cycle in the pancreatic tumor PANC-1 cell line.

The silencing of Pokemon attenuates the proliferation of hepatocellular carcinoma cells in vitro and in vivo by inhibiting the PI3K/Akt pathway.

Pokemon (POK erythroid myeloid ontogenic factor), which belongs to the POK protein family, is also called LRF, OCZF and FBI-1. As a transcriptional repressor, Pokemon assumes a critical function in cellular differentiation and oncogenesis. Our study identified an oncogenic role for Pokemon in human hepatocellular carcinoma (HCC). We successfully established human HepG2 and Huh-7 cell lines in which Pokemon was stably knocked down. We demonstrated that Pokemon silencing inhibited cell proliferation and migration. Pokemon knockdown inhibited the PI3K/Akt and c-Raf/MEK/ERK pathways and modulated the expression of various cell cycle regulators in HepG2 and Huh-7 cells. Therefore, Pokemon may also be involved in cell cycle progression in these cells. We confirmed that Pokemon silencing suppresses hepatocellular carcinoma growth in tumor xenograft mice. These results suggest that Pokemon promotes cell proliferation and migration in hepatocellular carcinoma and accelerates tumor development in an Akt- and ERK-signaling-dependent manner.

Comparison of various extraction methods for policosanol from rice bran wax and establishment of chromatographic fingerprint of policosanol.

A capillary gas chromatographic (GC) method has been developed for the separation and determination of policosanol components extracted from rice bran wax. A Varian CP-sil 8 CB column was employed, and an oven temperature was programmed. Gas chromatography-mass spectrometry (GC-MS) was used to identify the composition of policosanol. Quantitative analysis was carried out by means of hydrogen flame ionization detector (FID) with dinonyl phthalate (DNP) as internal standard. The results indicated that the extract obtained by dry saponification has the highest contents of octacosanol and triacontanol among extracts by all used extraction methods including dry saponification, saponification in alcohol, saponification in water (neutralized and non-neutralized), and transesterification. Meanwhile, the GC-MS fingerprint of policosanol extracted by dry saponification has been established. Euclidean distance similarity calculation showed remarkable consistency of compositions and contents among 12 batches of policosanol from a rice bran wax variety. This protocol provided a rapid and feasible method for quality control of policosanol products.