جستجوی مقالات مرتبط با کلیدواژه « HepG2 cells » در نشریات گروه « پزشکی »

Cinnamic acid, a phenylpropanoid acid, has been investigated as a potential alternative therapy for diabetes and its complications in some studies. 

In the first stage, the viability of HepG2 cells at different concentrations of glucose and CA was assessed by MTT assay. Oxidative stress markers) CAT, GPx, GSH, and MDA) were measured spectrophotometrically. After RNA extraction, the effect of different concentrations of CA on the expression of DPP4 and inflammatory factors (IL-6, NF- κB) in HepG2 cells was assessed using real-time PCR.

In HepG2 cells, CA increased catalase and glutathione peroxidase activity and GSH production in a dose-dependent manner in the presence of high glucose concentrations, with the greatest effect seen at a concentration of 75 mg/ml. Also, it reduced the amount of MDA in high-glucose HepG2 cells. Furthermore, CA decreased the expression of DPP4, NF- κB, and IL-6 genes in HepG2 cells in the presence of high glucose levels.

The results of our study indicated that CA reduced hyperglycemia-induced complications in HepG2 cells by decreasing inflammatory gene expression, including IL-6 and NF- κB and inhibiting the expression of DPP4, and limiting oxidative stress.

Liver cancer accounts for more than 700,000 deaths each year making it the third leading cause of cancer-related deaths worldwide. Late diagnosis of the disease is the reason behind most deaths. Driver mutations are genetic alterations in tumor cells, which are responsible for the development of liver cancer; therefore, the identification of genetic biomarkers is necessary for the prediction and early diagnosis of liver cancer.

The main objective of this study is to identify pathogenic alleles that may act as potential biomarkers for the prediction of liver cancer. It also identifies the role of novel genes in liver cancer that are not known to cause the disease.

The mutation data of non-coding variants were downloaded from the catalogue of somatic mutations in cancer (COSMIC) databases. Different bioinformatics tools were, then, used to retrieve mutations in liver cancer. The genetic alterations in hepatocellular carcinoma (HCC) were analyzed.

The present study successfully identified pathogenic alleles (consistent mutations) along with a set of novel genes that might be involved in the development of liver cancer. It identified non-coding mutations near human genes and transcription factor binding sites of HepG2 cells. This study also identified mutations near the genes that are involved in the Ras/MAFK signaling pathway of the Hepatitis B virus.

The pathogenic alleles identified in this study may provide targeted therapy for the treatment of liver cancer. The identification of novel genes may help to understand the progression of liver cancer at the molecular level. The identified driver mutations may act as potential biomarkers and therapeutic targets for early prediction and treatment of liver cancer.

 To investigate the effectiveness of Rhein on the proliferation, invasion and migration of human hepatoma cell line HepG2 and its possible mechanism.

 Human hepatoma cell line HepG2 was treated with different concentrations of Rhein (Rhein treatment group) and culture in culture medium alone (control group).The proliferation activity of the cells was determined by methyl Thiazolyl Tetrazolium (MTT) colorimetry.Transwell assay detected the invasion and migration of cells in each group.Cell scratch test was used to detect the migration ability of cells in each group.Excella-phospho-excellar signal-regulated kinase (P-ERK) activity was determined by ELISA after treatment with 50μ mol/L Rhein at different times.Western blot was used to detect ERK protein expression in HepG2 cells treated with 50 μmol/L Rhein.

 Compared with the control group, the proliferation activity, invasion and migration ability of HepG2 cells in the Rhein treatment group were all decreased (P< 0.05), and the p-ERK relative activity of HepG2 cells treated with Rhein was decreased (P < 0.05).

 Rhein inhibits the invasion and migration of HCC cells, possibly by inhibiting the ERK pathway.

Hyperglycemia is a severe consequence of diabetes mellitus (DM). Throughinduction of oxidative stress, it plays a major role in the pathogenesis of several complications in DM. Therefore, new strategies and antioxidants should be implemented inthe treatment of DM. Quercetin is a flavonoid with strong antioxidant capacity found dominantly in vegetables, fruits, leaves, and grains. The current study aimed to investigate quercetin protective effects under D-glucose-induced oxidative stress by assessing antioxidant defense enzymes inHepG2 cells as an in vitro model.
HepG2 cells were cultured with different concentrations of D-glucose (5.5, 30 and 50 mM) and/or 25 μM quercetin for 48 and 72 hr, respectively. The effect of treatments on cellular integrity, antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) activity, andcellular levels of glutathione (GSH) and malondialdehyde (MDA) wasdetermined.
D-glucose had various effects on intracellular antioxidant defense atdifferent doses and time-points and quercetin could attenuate oxidative stress and modulate antioxidant defenses.
The results of this study indicated that flavonoid quercetin could be proposed as an agent protecting hepatic HepG2 cells against oxidative stress associated with hyperglycemia.

The aim of this study was to evaluate and compare the hepatotoxicity as well as antioxidants activities of hydromethanolic extract of six common traditional species (Origanum vulgar, Pterocarya fraxinifolia, Ferula assafoetida, Artemisia dracunculus, Rosmarinus officinalis, and Valerian officinalis) in order to find a safe antioxidant source.
This research project was performed at Toxicology and Animal Poisoning Research Center, University of Tehran (Tehran, Iran), in 2016. The HepG2 cells viability was examined by LDH and MTT techniques following treatment with different concentrations of selected herbal hydroethanolic extracts for 72 h. Furthermore, assessment of antioxidative properties of the extracts was carried out by various scavenging models including DPPH and FRAP.
The highest cytotoxicity was displayed by F. asafoetida extract (IC50= 67.3 µg/ml). R. Officinalis and A. dracunculus extracts were noted as non-toxic due to the high effective dose. Interestingly, V. officinalis extract indicated stimulating effects on cell growth/ proliferation with ED50 values of 20.9 µ/ml. The highest and lowest antioxidant capacities refer to R. officinalis and V. officials. In DPPH assay, the IC50 value of R. officinalis and V. officinalis extracts was found to be 39.82 and 371.77 µg/ml, respectively. FRAP values of R. officinalis and V. officials were 2754.07 and 561.14 µM/g, respectively.
This study identified R. officinalis extract as a natural non-toxic agent with remarkable antioxidant potential in phytomedicine.

The protective effects of Artemia salina L. extract was examined against carbon tetrachloride (CCl4)-induced cell toxicity. In the in vitro model of study, markers such as cell viability, cellular reduced and oxidized glutathione, and lipid peroxidation in HepG2 cells was evaluated. Human liver cancer cell line HepG2 was treated with CCl4 and Artemia salina extract, and markers of hepatotoxicity were investigated. Artemia salina extract showed significant dose-dependent protective effects against the cytotoxicity of CCl4. This extract was able to normalize the levels of GSH, and thiobarbituric acid-reactive (TBARs), which were altered due to CCl4 intoxication in HepG2 cells. As the oxidative stress markers were ameliorated, it might be concluded that Artemia salina extract possesses protective effects probably due to its antioxidant constituents.

A potential treatment for healing hepatic tissue is delivering isolated hepatic cells to the site of injury to promote hepatic cells formation. In this technology, providing an appropriate injectable system for delivery of hepatic cells is an important issue. In this regard, fibrin scaffolds were designed with many advantages over other scaffolds like cell delivery vehicles for biodegradation, biocompatibility and hemostasis. The aim of this study was to determine suitable cell culture circumstances for HepG2 cell proliferation and differentiation in 3D fibrin scaffolds by evaluating Ca2+ concentrations, cell numbers, various ratios of plasma/RPMI 1640 and thickness of fibrin scaffold. In a one-stage experimental design, Box-Behnken design strategy was performed by Minitab 15 software (version 15, Minitab. State College, PA) with three factors at three levels (low, medium and high) and 27 runs for identification of the effects of ratio of plasma/RPMI 1640, Ca2+ concentration and thickness on the formation of fibrin gel scaffold and 3D HepG2 culture. The optimal concentrations for fibrin scaffold fabrication were achieved by adding 0.15 mol CaCl2 (50 µL) and 1 × 105 cells to 1:4 of plasma/RPMI 1640 ratio (500 µL with 2.3 mm thickness per well). Our approach provided easy handle method using inexpensive materials like human plasma instead of purified fibrinogen to fabricate fibrin scaffold.

Homocysteine is a sulfur-containing amino acid which formed (mainly in the liver) during the metabolism of methionine. Prior studies indicated the important role of hyperhomocysteinemia in pathogenesis and progression of alcoholic liver disease, liver steatosis and cirrhosis. One of the most important mechanisms by which homocysteine promote the development of hepatic injury is oxidative stress. Transcription factor Nrf2-mediated antioxidant response, represents critical cellular defense mechanism that serves to maintain intracellular redox homeostasis and limit oxidative stress. Glutamate cysteine ligase catalytic (GCLc) is rate limiting enzyme in the synthesis of glutathione, an important endogenous antioxidant..

This study was conducted to investigate whether homocysteine induces the Nrf2 dependent expression of GCLc in hepatoma cell line (HepG2) and whether this induction is mediated by antioxidant response element (ARE) which present within its promoter..

Glutathione (GSH) content was measured by flow cytometry. Using electro mobility shift assay (EMSA) and western blotting, ARE-binding activity of Nrf2 for GCLc was demonstrated. Real time RT-PCR and western blotting were performed to evaluate whether homocysteine was able to induce mRNA and protein expression of GCL..

Exposure of HepG2 cells to 50 µMD/L homocysteine and western blotting of nuclear extracts revealed that Nrf2 is strongly stabilized and became detectable in nuclear extracts. EMSA demonstrated increased binding of Nrf2 to oligomers containing GCL promoter - specific ARE -binding site.A time- dependent increase in the gene and protein expression of GCL was observed. Additionally, GSH, which is prime scavenger of free radicals in cells, decreased initially. Elevation of GSH, following the initial decline, closely correlated with gene expression profile of GCLc, which is a rate-limiting enzyme in GSH synthesis..

Altogether, we provide direct evidence that homocysteine activates Nrf2-mediated antioxidant response, which protects HepG2 cells from oxidative damage..

The hepatitis B virus X (HBx) protein has long been recognized as an important transcriptional transactivator of several genes. Human aldo-keto reductase family 1, member C1 (AKR1C1), a member of the family of AKR1CS, is significantly increased in HBx-expressed cells..

This study aimed to investigate the possible mechanism of HBx in regulating AKR1C1 expression in HepG2.2.15 cells and the role of AKR1C1 for HBV-induced HCC..

RT-PCR was performed to detect AKR1C1 expression on mRNA level in HepG2 and HepG2.2.15 cell. The promoter activity of AKR1C1 was assayed by transient transfection and Dual-luciferase reporter assay system. The AKR1C1 promoter sequence was screened using the TFSEARCH database and the ALIBABA 2.0 software. The potential transcription factors binding sites were identified using 5’ functional deletion analysis and site-directed mutagenesis..

In this study, we found that HBx promoted AKR1C1 expression in HepG2.2.15 cells. Knockdown of HBx inhibited AKR1C1 activation. The role of HBx expression in regulating the promoter activity of human AKR1C1 gene was analyzed. The 5’functional deletion analysis identified that the region between -128 and -88 was the minimal promoter region of HBx to activate AKR1C1 gene expression. Site-directed mutagenesis studies suggested that nuclear factor-Y (NF-Y) plays an important role in this HBx-induced AKR1C1 activation..

In HepG2.2.1.5 cell, HBx can promote AKR1C1 promoter activity and thus activates the basal transcription of AKR1C1 gene. This process is mediated by the transcription factor NF-Y. This study explored the mechanism for the regulation of HBV on AKR1C1 expression and has provided a new understanding of HBV-induced HCC..

Elevated level of plasma homocysteine has been related to various diseases. Patients with hyperhomocysteinemia can develop hepatic steatosis and fibrosis. We hypothesized that oxidative stress induced by homocysteine might play an important role in pathogenesis of liver injury. Also، the cellular response designed to combat oxidative stress is primarily controlled by the transcription factor Nrf2، a principal inducer of anti-oxidant and phase II-related genes. HepG2 cells were treated with homocysteine in different time periods. Glutathione content was measured by flowcytometry. Using electrophoretic mobility shift assay (EMSA) and Western-blotting، anti-oxidant response element (ARE) -binding activity of Nrf2 for heme ocygenase-1 (HO-1) was demonstrated. Real time RT-PCR and Western-blotting were performed to evaluate whether homocysteine was able to induce mRNA and protein expression of HO-1. The role of Nrf2 in cellular response to homocysteine is substantiated by the following observations in HepG2 cells exposed to homocysteine (i) Western-blotting revealed that Nrf2 is strongly stabilized and became detectable in nuclear extracts. (ii) EMSA demonstrated increased binding of Nrf2 to oligomers containing HO-1 promoter-specific ARE-binding site. (iii) Real time RT-PCR and Western-blotting revealed increased mRNA and protein expression of inducible gene HO-1 after treatment with homocysteine. Data presented in the current study provide direct evidence that the immediate cellular response to oxidative stress provoked by homocysteine is orchestrated mainly by the Nrf2-ARE pathway. Therefore، induction of Nrf2-ARE-dependent expression of HO-1 could be a therapeutic option for hepatic cells damage induced by homocysteine.

In the recent decades, a lot of efforts have been directed for the discovery and production of anticancer agents. Plant kingdom is one of the main sources which has attracted the attention of investigators for finding new medicines including anticancer agents. In the present study, the cytotoxic effects of the extracts of five plants, native of Iran including Salvia mirzayanii, S. macrosiphon, S. multicaulis, Juniperus excels, and Peganum harmala, against HepG2 cell lines were investigated. Cytotoxicity was assessed by MTT test, and comparison of the IC50s revealed that the extracts of aerial parts of the J. excelsa had the strongest cytotoxic effects followed by S. mirzayanii, and the extract of the root of P. harmala with IC50s of 0.54, 1.52, and 2.50 mg/ml, respectively. The extracts of S. macrosiphon and S. multicaulishad no significant cytotoxic effects against HepG2 cells. The cytotoxic effects of J. excelsais seemed to be due to ATP depletion as ATP levels of HepG2 cells incubated for 24 h with 0.5, and 0.7 mg/ml of the extracts of J. excelsa was decreased to 47% and 27% of control, respectively. The ATP depletion was timedependent and ATP was depleted before cytotoxicity ensued. Oxidative stress was not important in cytotoxicity of J. excelsaas lipid peroxidation and GSH depletion was not significantly different from control cells. However, cytotoxicity of S. mirzayanii was not accompanied by ATP depletion or oxidative stress. The exact mechanism(s) of cytotoxicity of these extracts needs further investigation.

Punica granatum is used as a medicinal plant, and its fruit concentrate has been used for the prevention and treatment of liver diseases in Iran. The effects of different concentrations of the hydroalcoholic, ethyl acetate and n-hexane extracts of the Punica granatum (fruit juice and seed) were investigated against CCl4- induced cytotoxicity in HepG2 cells. Concentrations (1-10000 µg/ml) of the extracts were added to the cells, 1 h before the addition of 100 mM of CCl4. After 24 h, the cells were evaluated for toxicity, TBARs level and GSH content. The hydroalcoholic extracts of fruit juice and seeds with concentrations of 100 to 1000 µg/ml protected the cells against CCl4 induced cytotoxicity, but the ethyl acetate extract of fruit juice   with higher concentration (1000 µg/ml) protected the cells against CCl4 cytotoxicity and the n-hexane extracts were less effective. The ethyl acetate and n-hexane extracts of seeds with different concentrations did not have any significant protective effect. The Punica granatum extracts themselves were not toxic towards cells with concentrations up to 1 mg/ml. Therefore, the results of the present study are somehow consistent with traditional beliefs about hepatoprotective effects of Punica granatum.