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•DG improves lipid accumulation in in vitro and in vivo MAFLD models.•DG ameliorates liver function impairment.•DG inhibits the NLRP3-dependent signaling pathway.•Silencing or ...overexpressing NLRP3 affects the antiMAFLD effect of DG.•DG may play a beneficial role as a natural NLRP3 inhibitor.
Metabolic-associated fatty liver disease (MAFLD) is one of the most common liver diseases worldwide; however, its pathogenesis and treatment methods have not been perfected. NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) is a promising therapeutic target for MAFLD. Diosgenin (DG) is a natural compound that was identified in a traditional Chinese herbal medicine, which has pharmacological effects, such as anti-inflammatory, antioxidant, hepatoprotective, and hypolipidemic activities. In this study, we examined the effects and molecular mechanisms of DG on MAFLD in vitro and in vivo. We established a rat model by administering a high-fat diet (HFD). We also generated an in vitro MAFLD model by treating HepG2 cells with free fatty acids (FFAs). The results indicated that DG attenuated lipid accumulation and liver injury in both in vitro and in vivo models. DG downregulated the expression of NLRP3, apoptosis-associated speckle-like protein (ASC), cysteinyl aspartate specific proteinase-1 (caspase-1), gasdermin D (GSDMD), GSDMD-n, and interleukin-1β (IL-1β). In addition, we silenced and overexpressed NLRP3 in vitro to determine the effects of DG on antiMAFLD. Silencing NLRP3 enhanced the effect of DG on the treatment of MAFLD, whereas NLRP3 overexpression reversed its beneficial effects. Taken together, the results show that DG has a favorable effect on attenuating MAFLD through the hepatic NLRP3 inflammasome-dependent signaling pathway. DG represents a natural NLRP3 inhibitor for the MAFLD treatment.
1,3,6,8-Tetrabromocarbazole (1368-BCZ) is identified as an emerging contaminant that exerts angiogenic effects. Multiple studies indicated there was a positive correlation between angiogenesis and ...nuclear factor kappa B (NF-κB) activation. While the role of NF-κB in inflammation and apoptosis has been well known, the potential biological effects of 1368-BCZ on NF-κB signaling and related mechanism remain unclear. We, therefore, explored the possible effects of 1368-BCZ on the NF-κB pathway at the gene and protein levels and confirmed that NF-κB activation by 1368-BCZ exposure caused an augmented phosphorylated protein level, induction of NF-κB response element (κBRE)-driven luciferase activity and upregulation of transcriptional level of downstream responsive genes. Although 1368-BCZ did not produce detectable changes in hepatic fibrosis in vivo, it obviously altered the apoptosis in human hepatocellular carcinoma (HepG2) cells. Furthermore, the induction of apoptosis was confirmed by the increased cleaved caspase-3 level. These data revealed the activating effects of 1368-BCZ on NF-κB and its involvement in the underlying mechanisms, providing additional information for toxicology studies of emerging contaminants and introducing a mechanism-based toxicological evaluation of emerging pollutants.
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•1368-BCZ upregulated the level of phosphorylated NF-κB protein.•1368-BCZ induced transcriptional activation of the NF-κB signaling pathway.•1368-BCZ increased the induction of apoptosis.•1368-BCZ enhanced the cleaved caspase-3 level.
A green method by Verbascum speciosum was used to synthesize zinc oxide nanoparticles (ZnO NPs). ZnO NPs were coated with silver to synthesize Ag–ZnO nanocomposite (NCs). The physicochemical ...properties of Ag–ZnO NCs were analyzed by Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential. The FTIR indicated the peak of Zn–O vibration and some hydroxyl and carboxyl groups. PXRD analyses confirmed the synthesis of ZnO NPs and Ag–ZnO NCs. Due to the size of the crystallite obtained from PXRD, solid-phase sizes (from FESEM and TEM images), and dynamic sizes from DLS, agglomeration was observed. The Ag–ZnO NCs showed a negative charge surface (−49.3 mV). Ag–ZnO NCs had a high antibacterial activity towards two most important infectious bacteria (i.e., Escherichia coli and Staphylococcus aureus) and anticancer activity against human liver-carcinoma cells (HepG2). Later, it depended on time and concentration of Ag–ZnO NCs. The cytotoxicity properties of Ag–ZnO NCs were also studied against NIH-3T3 as a normal cell, where the results verified the lower cell toxicities of nanocomposite than the HepG2.
The aptamers generated from HepG2 cells Huang, Rongrong; Chen, Zhongsi; Liu, Mei ...
Science China. Chemistry,
06/2017, Volume:
60, Issue:
6
Journal Article
Peer reviewed
Liver cancer, as the second cause of cancer death all around the world, resulted in a series of chronic liver diseases. More than 80%of the patients cannot receive effective treatment because of ...their advanced disease or poor liver function. It is time to improve early clinical diagnosis and find optimal therapeutic treatments. As the tumor cells behave differently from the cell-surface molecules, it is necessary to find a highly specific probe. The aptamers, known as ＂chemical antibodies＂, can bind to their target molecules with high affinity and high specificity. The apatmers were obtained by Cell-SELEX, which was aimed at finding the aptamers against whole living cells. In the article, after 19 selections, the ssDNA pool was cloned and sequenced. After that, six aptamers were obtained, named apt_A to apt_F. By incubating the aptamers with different cells, except apt_E, the other aptamers showed high specificity. As for apt_E, which showed high affinity to several cancer cells, was a potential probe for the common protein presented by several different cancer cells. The equilibrium dissociation constants（Kd） were evaluated by measuring the flow cytometry signal that characterized the binding ability of aptamers to the target cells at a series of concentrations ranging from 46.3（4.5） nM to 199.4（44.2） nM, which exposed the high binding affinities of these aptamers. The research in the confocal fluorescence images further confirmed the specificity of these aptamers and the fact that the aptamers were combined with the targets on the cell-surface.
Previous work showed that peptides from duck eggs incubated for 15 D presented high total antioxidant activities. Here, this work explore the antioxidant activities of different segments, ZT1 (≤3 ...KD), ZT2 (≤10 KD), and ZT3 (≤30 KD), derived from duck embryo peptides and their protective effects against H2 O2-induced oxidative damage in HepG2 cells. Peptides present no cytotoxicity to HepG2 cells. Moreover, ZT1 exhibits a higher ability to scavenge several radicals as well as stronger inhibition of H2 O2-induced oxidative stress than ZT2 and ZT3. The activities of catalase and glutathione peroxidase as well as total superoxide dismutase increase in a concentration-dependent manner. Peptides are isolated from ZT1 and then subjected to LC-MS/MS to identify their sequences, followed by functional annotation, bioinformatics prediction, and hot-spot motif recognition. As a result, 413 potential functional peptides are identified, with some compounds exhibiting more than 1 function. This work will help for exploring bioactive substances in duck embryo eggs and enhance the utilization value of duck or other poultry eggs.
Coenzyme Q10 (CoQ10) is a strongly hydrophobic lipid that functions in the electron transport chain and as an antioxidant. CoQ10 was conferred with aqueous solubility by incorporation into ...nanoparticles containing phosphatidylcholine (PtdCho) and apolipoprotein (apo) A‐I. These particles, termed CoQ10 nanodisks (ND), contain 1.0 mg CoQ10/5 mg PtdCho/2 mg apoA‐I (97% CoQ10 solubilization efficiency). UV/Vis absorbance spectroscopy of CoQ10 ND revealed a characteristic absorbance peak centered at 275 nm. Incorporation of CoQ10 into ND resulted in quenching of apoA‐I tryptophan fluorescence emission. Gel filtration chromatography of CoQ10 ND gave rise to a single major absorbance peak and HPLC of material extracted from this peak confirmed the presence of CoQ10. Incubation of cultured cells with CoQ10 ND, but not empty ND, resulted in a significant increase in the CoQ10 content of mitochondria as well as enhanced oxidative phosphorylation, as observed by a ~24% increase in maximal oxygen consumption rate. Collectively, a facile method to solubilize significant quantities of CoQ10 in lipid nanoparticles has been developed. The availability of CoQ10 ND provides a novel means to investigate biochemical aspects of CoQ10 uptake by cells and/or administer it to subjects deficient in this key lipid as a result of inborn errors of metabolism, statin therapy, or otherwise.
Pyraclostrobin is a highly effective and broad-spectrum strobilurin fungicide. With the widespread use of pyraclostrobin to prevent and control crop diseases, its environmental pressure and potential ...safety risks to humans have attracted much attention. Herein, the toxicological risks of pyraclostrobin toward HepG2 cells and the mechanisms of intoxication in vitro were investigated. The liver toxicity of pyraclostrobin in zebrafish larvae was also evaluated. It was found that pyraclostrobin induced DNA damage and reactive oxygen species generation in HepG2 cells, indicating the potential genotoxicity of pyraclostrobin. The results of fluorescent staining experiments and the expression of cytochrome c, Bcl-2 and Bax demonstrated that pyraclostrobin induced mitochondrial dysfunction, resulting in cell apoptosis. Monodansylcadaverine staining and autophagy marker-related proteins LC3, p62, Beclin-1 protein expression showed that pyraclostrobin promoted cell autophagy. Furthermore, immunoblotting analysis suggested that pyraclostrobin induced autophagy accompanied with activation of adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK)/mTOR signaling pathway. Visualization of zebrafish liver and oil red staining indicated that pyraclostrobin could induce liver degeneration and liver steatosis in zebrafish. Collectively, these results help to better understand the hepatotoxicity of pyraclostrobin and provide a scientific basis for its safe applications and risk control.
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•Pyraclostrobin exhibited toxic effects in HepG2 cell lines and zebrafish larvae.•Pyraclostrobin induced oxidative DNA damage and mitochondrial dysfunction in HepG2 cells.•Pyraclostrobin induced autophagy through the activation of AMPK/mTOR signaling.•Pyraclostrobin caused the liver toxicity and induced liver steatosis in zebrafish larvae.
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•PFAS causes dose-dependent, non-monotonic responses on multiple metabolites.•PFAS exposure is linked with changes in bile acid and glucose metabolism.•PFAS exposure is linked with ...oxidative stress and inflammatory response.•PFAS exposure has impacts on cell morphology.
PFAS are ubiquitous industrial chemicals with known adverse health effects, particularly on the liver. The liver, being a vital metabolic organ, is susceptible to PFAS-induced metabolic dysregulation, leading to conditions such as hepatotoxicity and metabolic disturbances. In this study, we investigated the phenotypic and metabolic responses of PFAS exposure using two hepatocyte models, HepG2 (male cell line) and HepaRG (female cell line), aiming to define phenotypic alterations, and metabolic disturbances at the metabolite and pathway levels. The PFAS mixture composition was selected based on epidemiological data, covering a broad concentration spectrum observed in diverse human populations. Phenotypic profiling by Cell Painting assay disclosed predominant effects of PFAS exposure on mitochondrial structure and function in both cell models as well as effects on F-actin, Golgi apparatus, and plasma membrane-associated measures. We employed comprehensive metabolic characterization using liquid chromatography combined with high-resolution mass spectrometry (LC-HRMS). We observed dose-dependent changes in the metabolic profiles, particularly in lipid, steroid, amino acid and sugar and carbohydrate metabolism in both cells as well as in cell media, with HepaRG cell line showing a stronger metabolic response. In cells, most of the bile acids, acylcarnitines and free fatty acids showed downregulation, while medium-chain fatty acids and carnosine were upregulated, while the cell media showed different response especially in relation to the bile acids in HepaRG cell media. Importantly, we observed also nonmonotonic response for several phenotypic features and metabolites. On the pathway level, PFAS exposure was also associated with pathways indicating oxidative stress and inflammatory responses. Taken together, our findings on PFAS-induced phenotypic and metabolic disruptions in hepatocytes shed light on potential mechanisms contributing to the broader comprehension of PFAS-related health risks.
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