Rat Hepatoma Cells Research Articles

Cytotoxicity, chemical, and nutritional profile evaluation of biomass extracts of the Lemna aequinoctialis (duckweed) aquatic plant

ABSTRACT Lemna aequinoctialis (duckweed) is the smallest and fast-growing aquatic plant species producing protein-rich biomass with high protein nutritional value, phytoremediation capacity, and nutrient removal from wastewater. Duckweed may also be used as a new potential bioreactor for biological products, such as vaccines, antibodies, and pharmaceutical proteins. Based upon the potential importanc of L. aequinoctialis in phytoremediation and as a bioreactor the aim of this study was to (1) characterize the chemical and nutritional profiles of L. aequinoctialis biomass utilizing an integrated multi-trophic aquaculture system (IMTA) and a pond, and (2) investigate the cytotoxic potential of different concentrations of organic extracts and fractions using the MTT bioassay. EDXRF and ICP-MS analyses indicated the presence of trace elements in lower amounts in relation to the biomass of L. aequinoctialis in the lagoon, emphasizing the importance of plant inclusion management to reduce bioaccumulation of these elements. Analysis of mineral profiles, fatty acids, and amino acids indicated a satisfactory nutritional composition for the use of biomass as a bioproduct. Pigment analysis showed a high concentration of carotenoids, especially astaxanthin. After standardizing the controls, the MTT cell viability test was carried out utilizing rat hepatoma cell line (HTC), which are metabolizing cells that were treated with aqueous or ethanolic extracts and the dichloromethane, ethyl acetate, and methanol fractions at different concentrations. No apparent cytotoxic potential was observed following treatments, since there was no significant reduction in cell viability. Therefore, this study provides information regarding the biomass of L. aequinoctialis derived from the IMTA system, which might support further research into the application of this species as a bioproduct.

Knockdown and Overexpression Experiments to Investigate the Inhibitory Mechanism of Fuzheng Xiaozheng Prescription, an Effective Chinese Herbal Formula for the Clinical Treatment of Hepatocellular Carcinoma.

Fuzheng Xiaozheng prescription (FZXZP) is an effective formula for the treatment of different kinds of chronic liver diseases. However, its potential molecular mechanisms in treating hepatocellular carcinoma (HCC) have not been investigated thoroughly. The aim of this study is to elucidate the targets and intrinsic mechanisms of FZXZP and their active components for the treatment of HCC. The efficacy of FZXZP against HCC was clarified through a rat HCC model and HCC cell culture. Network pharmacology and molecular docking were utilized to predict the mechanism of action and effector components of FZXZP. The key mechanism and targets were verified by the construction of overexpression and knockout cell models. The results showed that FZXZP greatly delayed the development of HCC in vivo experiments, as evidenced by biochemical evaluations, H&E analyses and growth inhibition of HCC. FZXZP dramatically inhibited cell viability and proliferative capacity and induced the apoptosis of hepatoma cells in vitro. Moreover, network pharmacology analyses demonstrated that the EGFR family and apoptosis-related targets were found to be the most significant in bioinformatics analysis. Furthermore, the EGFR/STAT3 signal axis might be the most likely target of FZXZP in anti-HCC due to the fact that it could be down-regulated by FZXZP with an upward trend of Bax, Caspase-3, Caspase-8, Caspase-9 and an inverse trend of Bcl2. Importantly, the above targeted signal axis was finally validated by our knockdown and overexpression analyses. Meanwhile, flow cytometry and TUNEL staining also revealed that FZXZP significantly induced apoptosis in the EGFR-overexpressing HCC cell line. The molecular docking results revealed that the key effector components of FZXZP that exerted the above regulatory roles were wogonin and glycitein. All of these results suggest that FZXZP could significantly delay HCC development by inhibiting proliferation and promoting apoptosis of HCC cells, and the EGFR/STAT3 signal axis might be a critical signal axis of FZXZP in suppressing HCC progression.

Comparison of in vitro Toxicities of 8-Prenylnaringenin, Tartrazine and 17β-Estradiol, Representatives of Natural and Synthetic Estrogens, in Rat and Human Hepatoma Cell Lines

ABSTRACT Background: Phytoestrogens have been praised for their beneficial health effects, whereas synthetic xenoestrogens have been connected to ailments. Aims: To ascertain whether the toxicities of natural and synthetic estrogens differ, we examined the potent phytoestrogen 8-prenylnaringenin (8-PN), the common synthetic xenoestrogen tartrazine, and the physiological estrogen 17β-estradiol (E2). Methods: These three compounds were tested for cytotoxicity, cell proliferation and genotoxicity in human HepG2 and rat H4IIE hepatoma cells. Results: All three estrogens elicited cytotoxicity at high concentrations in both cell lines. They also inhibited cell proliferation, with E2 being the most effective. They all tended to increase micronuclei formation. Conclusion: Natural estrogens were no less toxic than a synthetic one.

Molecularly generated rat hepatitis E virus strains from human and rat show efficient replication in a human hepatoma cell line

The hepatitis E virus (HEV) can cause acute and chronic hepatitis in humans. Whereas HEV genotypes 1–4 of species Paslahepevirus balayani are commonly found in humans, infections with ratHEV (species Rocahepevirus ratti) were previously considered to be restricted to rats. However, several cases of human ratHEV infections have been described recently. To investigate the zoonotic potential of this virus, a genomic clone was constructed here based on sequence data of ratHEV strain pt2, originally identified in a human patient with acute hepatitis from Hongkong. For comparison, genomic clones of ratHEV strain R63 from a rat and of HEV genotype 3 strain 47832mc from a human patient were used. After transfection of in vitro-transcribed RNA from the genomic clones into the human hepatoma cell line HuH-7-Lunet BLR, virus replication was shown for all strains by increasing genome copy numbers in cell culture supernatants. These cells developed persistent virus infections, and virus particles in the culture supernatant as well as viral antigen within the cells were demonstrated. All three generated virus strains successfully infected fresh HuH-7-Lunet BLR cells. In contrast, the human hepatoma cell lines HuH-7 and PLC/PRF/5 could only be infected with the genotype 3 strain and to a lesser extent with ratHEV strain R63. Infection of the rat-derived hepatoma cell lines clone 9, MH1C1 and H-4-II-E did not result in efficient virus replication for either strain. The results indicate that ratHEV strains from rats and humans can infect human hepatoma cells. The replication efficiency is strongly dependent on the cell line and virus strain. The investigated rat hepatoma cell lines could not be infected and other rat-derived cells should be tested in future to identify permissive cell lines from rats. The developed genomic clone can represent a useful tool for future research investigating pathogenicity and zoonotic potential of ratHEV.

Growth hormone resistance induced by amino acid deprivation in fao cells is independent of FGF21

Adequate dietary intake of amino acids is imperative for normal animal growth. Our previous work using rat hepatocarcinoma Fao cells demonstrated that growth hormone (GH) resistance, coupled with a concurrent reduction in insulin-like growth factor 1 (Igf1) mRNA levels, may underlie the growth retardation associated with a low-protein diet (LPD). In this study, we investigated whether FGF21 contributes to liver GH resistance in Fao rat hepatoma cells under amino acid deprivation conditions. Mice subjected to an LPD exhibited growth retardation, compromised GH signaling in the liver, and decreased blood IGF-1 levels compared with those on a control diet. To assess the potential involvement of fibroblast growth factor (FGF) 21, produced in response to amino acid deficiency, in the development of GH resistance, we examined GH signaling and Igf1 mRNA levels in Fao cells cultured in amino acid-deprived medium. Despite the inhibition of Fgf21 expression by the integrated stress response inhibitor, an inhibitor of the eukaryotic initiation factor 2-activating transcription factor 4 pathway, GH resistance persisted in response to amino acid deprivation. Additionally, the introduction of FGF21 into the control medium did not impair either GH signaling or GH-induced Igf1 transcription. These data suggest that, in Fao cells, amino acid deprivation induces GH resistance independently of FGF21 activity. By shedding light on the mechanisms behind growth retardation-associated GH resistance linked to amino acid deficiencies, our findings provide valuable insights for clinicians in formulating effective treatment strategies for individuals facing these challenges.

Abstract 5547: Non-invasive monitoring of tumor biomechanics and implications for immunotherapy in HCC

Abstract Shear-wave elastography (SWE) is a novel non-invasive technique used to quantify tissue stiffness. This approach can be used to longitudinally monitor tumor biomechanics and holds promise for guiding informed clinical decision-making. This study aims to explore the impact of tumor stiffness, as evaluated by SWE, on the proliferative potential of endothelial, tumor, and immune cells in a preclinical model of hepatocellular carcinoma. Tumor tissue sections from a Buffalo-McA-RH7777 rat HCC tumor model, utilizing a rat hepatoma cell line stably expressing green fluorescent protein genes (fluc/GFP) were selected based on the degree of tumor stiffness assessed by SWE. Nodules were separated based on mean shear wave values (3.05 versus 2.26 m/s) and categorized as stiff or soft, respectively. A 6-color panel was used to assess the percentages of different tumor, immune, and endothelial phenotypes in different areas of the tumor including immune cells (CD45+), endothelial cells (CD34+), green fluorescent protein (GFP), Ki67 (cell proliferation), and class-III intermediate filaments - vimentin. Our findings demonstrated increased expression of vimentin on immune cells (CD45+) within the tumor margin interphase. Stiffer tumors exhibited a higher percentage of CD45 cells co-expressing vimentin compared to softer tumors (P=0.01), whereas softer tumors showed an increased prevalence of CD34+ cells concurrently expressing Ki67 (P=0.01). Same pattern persisted in the tumor margin interphase regarding the proliferation of tumor cells identified by the expression of GFP co-expressing Ki67 (P<0.01). These findings highlight a significant association between tumor mechanical properties and the proliferative activity of endothelial and tumor cells, suggesting a link between tissue stiffness and the regulatory mechanisms associated with cellular proliferation and aggressiveness in HCC. Additionally, the presence of vimentin in immune cells may suggest that stiffer tumors may require enhanced migratory and invasive properties to compensate for changes in tumor mechanics thus potentially influencing immune function. Citation Format: Andrea C. Cortes, Kiyoyuki Minamiguchi, Hannah Kostan, Maria S. Stenkamp, Simone Anfossi, Natalie Wall Fowlkes, Rony Avritcsher. Non-invasive monitoring of tumor biomechanics and implications for immunotherapy in HCC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5547.

Development of an immunosuppressed orthotopic hepatocellular carcinoma rat model for the evaluation of chemo- and radioembolization therapies

Hepatocellular carcinoma (HCC) is widely known to be chemo-resistant and presents with significant liver disease resulting in low tolerability to systemic chemotherapy. As a counter measure, more targeted therapies such as trans-arterial chemoembolization (TACE) and trans-arterial radioembolization (TARE) have been developed. To further optimize these therapies, animal models are critical in elucidating the molecular events in disease progression and test new treatment options. The present study focuses on the development of a hepatoma bearing rat model. N1S1 rat hepatoma cells were transfected by a lentiviral method and injected into the liver of Sprague Dawley (SD) and Rowett Nude (RNU) rats. Longitudinal tumor growth was observed by bioluminescence imaging (BLI) and liver/tumor histology. In both models, tumors were visible within 4 days post cell inoculation. Tumor take rates were 52 % and 73 % for male and female SD rats, respectively, and 100 % for male RNU rats. By day 12 and 15 post inoculation, we recorded complete tumor regression in male and female SD rats. Liver histology showed advanced fibrosis in the tumor regressed SD rats, whilst RNU rats exhibited the characteristic sheet pattern of Novikoff tumor with mild liver fibrosis. Increased CD3 and TUNEL staining observed in SD rat livers may be key factors for tumor regression. Our data reveal that the immunocompetent SD rats are not recommended as a model for therapeutic investigations. The immunosuppressed RNU rats, however, are characterized by consistent and reliable tumor growth and thus a desirable model for future therapeutic investigations.

Effect of sunitinib against Echinococcus multilocularis through inhibition of VEGFA-induced angiogenesis

BackgroundAlveolar echinococcosis (AE) is a lethal zoonosis caused by the fox tapeworm Echinococcus multilocularis. The disease is difficult to treat, and an effective therapeutic drug is urgently needed. Echinococcus multilocularis-associated angiogenesis is required by the parasite for growth and metastasis; however, whether antiangiogenic therapy is effective for treating AE is unclear.MethodsThe in vivo efficacy of sunitinib malate (SU11248) was evaluated in mice by secondary infection with E. multilocularis. Enzyme-linked immunosorbent assays (ELISAs) were used to evaluate treatment effects on serum IL-4 and vascular endothelial growth factor A (VEGFA) levels after SU11248 treatment. Gross morphological observations and immunohistochemical staining were used to evaluate the impact of SU11248 on angiogenesis and the expression of pro-angiogenic factors VEGFA and VEGF receptor 2 (VEGFR2) in the metacestode tissues. Furthermore, the anthelmintic effects of SU11248 were tested on E. multilocularis metacestodes in vitro. The effect of SU11248 on the expression of VEGFA, VEGFR2, and phosphorylated VEGFR2 (p-VEGFR2) in liver cells infected with protoscoleces in vitro was detected by western blotting, reverse transcription quantitative polymerase chain reaction (RT-qPCR), and enzyme-linked immunosorbent assay (ELISA). The influence of SU11248 on endothelial progenitor cell (EPC) proliferation and migration was determined using CCK8 and transwell assays.ResultsIn vivo, SU11248 treatment markedly reduced neovascular lesion formation and substantially inhibited E. multilocularis metacestode growth in mice. Further, it exhibited high anti-hydatid activity as efficiently as albendazole (ABZ), and the treatment resulted in reduced protoscolex development. In addition, VEGFA, VEGFR2, and p-VEGFR2 expression was significantly decreased in the metacestode tissues after SU11248 treatment. However, no effect of SU11248 on serum IL-4 levels was observed. In vitro, SU11248 exhibited some anthelmintic effects and damaged the cellular structure in the germinal layer of metacestodes at concentrations below those generally considered acceptable for treatment (0.12–0.5 μM). Western blotting, RT-qPCR, and ELISA showed that in co-cultured systems, only p-VEGFR2 levels tended to decrease with increasing SU11248 concentrations. Furthermore, SU11248 was less toxic to Reuber rat hepatoma (RH) cells and metacestodes than to EPCs, and 0.1 μM SU11248 completely inhibited EPC migration to the supernatants of liver cell and protoscolex co-cultures.ConclusionsSU11248 is a potential candidate drug for the treatment of AE, which predominantly inhibits parasite-induced angiogenesis. Host-targeted anti-angiogenesis treatment strategies constitute a new avenue for the treatment of AE.Graphical

St. John's wort formulations induce rat CYP3A23-3A1 independent of their hyperforin content.

The pregnane X receptor (PXR) is a ligand activated regulator of cytochrome P450 (CYP)3A enzymes. Among the ligands of human PXR is hyperforin, a constituent of St John's wort (SJW) extracts and potent inducer of human CYP3A4. It was the aim of this study to compare the effect of hyperforin and SJW formulations controlled for its content on CYP3A23-3A1 in rats. Hyperiplant® was used as it contains a high hyperforin content and Rebalance® because it is controlled for a low hyperforin content. In silico analysis revealed a weak hyperforin-rPXR binding affinity, which was further supported in cell-based reporter gene assays showing no hyperforin-mediated reporter activation in presence of rPXR. However, cellular exposure to Hyperiplant® and Rebalance® transactivated the CYP3A-reporter 3.8 fold and 2.8 fold, respectively, and they induced Cyp3a23-3a1 mRNA expression in rat hepatoma cells compared to control 48-fold and 18-fold, respectively. In Wistar rats treated for 10 days with 400 mg/kg of Hyperiplant® we observed 1.8-times the Cyp3a23-3a1 mRNA expression, a 2.6-fold higher CYP3A23-3A1 protein amount and a 1.6-fold increase in activity compared to control. For Rebalance® we only observed a 1.8-fold hepatic increase of CYP3A23-3A1 protein compared to control animals. Even though there are differing effects on rCyp3a23-3a1/CYP3A23-3A1 in rat liver reflecting the hyperforin content of the SJW extracts, the modulation is most likely not linked to an interaction of hyperforin with rPXR. Significance Statement Treatment with St John's wort (SJW) has been reported to affect CYP3A expression and activity in rats. Our comparative study further supports this finding but shows that the PXR-ligand hyperforin is not the driving force for changes in rat CYP3A23-3A1 expression and function in vivo and in vitro Importantly, CYP3A induction mimics findings in humans but our results suggest that another so far unknown constituent of SJW is responsible for the expression and function modifying effects in rat liver.

New fatty acid ester and meroterpenoid produced by the endophytic fungus Penicillium sp. NR-1

New fatty acid ester and meroterpenoid derivatives (1 and 2), and seven known compounds, including five meroterpenoids (3−7), one sesquiterpenoid (8), and one fatty acid ester derivative (9), were isolated from the endophytic strain of Penicillium sp. NR-1. The structures of the new and known compounds, including their absolute configurations, were elucidated by NMR, IR, UV, MS and ECD, and chemical methods. Cytotoxicity, glucose production in rat hepatocellular carcinoma (H4IIE) cells, and calcineurin inhibitory activity of the isolated compounds were evaluated. These results indicate that compounds 1–7 may be less toxic anti-type-2 diabetic agents.

Metformin Induces Lipogenesis and Apoptosis in H4IIE Hepatocellular Carcinoma Cells.

Metformin is the most widely used anti-diabetic drug that helps maintain normal blood glucose levels primarily by suppressing hepatic gluconeogenesis in type II diabetic patients. We previously found that metformin induces apoptotic death in H4IIE rat hepatocellular carcinoma cells. Despite its anti-diabetic roles, the effect of metformin on hepatic de novo lipogenesis (DNL) remains unclear. We investigated the effect of metformin on hepatic DNL and apoptotic cell death in H4IIE cells. Metformin treatment stimulated glucose consumption, lactate production, intracellular fat accumulation, and the expressions of lipogenic proteins. It also stimulated apoptosis but reduced autophagic responses. These metformin-induced changes were clearly reversed by compound C, an inhibitor of AMP-activated protein kinase (AMPK). Interestingly, metformin massively increased the production of reactive oxygen species (ROS), which was completely blocked by compound C. Metformin also stimulated the phosphorylation of p38 mitogen-activated protein kinase (p38MAPK). Finally, inhibition of p38MAPK mimicked the effects of compound C, and suppressed the metformin-induced fat accumulation and apoptosis. Taken together, metformin stimulates dysregulated glucose metabolism, intracellular fat accumulation, and apoptosis. Our findings suggest that metformin induces excessive glucose-induced DNL, oxidative stress by ROS generation, activation of AMPK and p38MAPK, suppression of autophagy, and ultimately apoptosis.

Non-Viral Gene Delivery to Hepatocellular Carcinoma via Intra-Arterial Injection.

Hepatocellular carcinoma (HCC) has limited treatment options, and modest survival after systemic chemotherapy or procedures such as transarterial chemoembolization (TACE). There is therefore a need to develop targeted therapies to address HCC. Gene therapies hold immense promise in treating a variety of diseases, including HCC, though delivery remains a critical hurdle. This study investigated a new approach of local delivery of polymeric nanoparticles (NPs) via intra-arterial injection for targeted local gene delivery to HCC tumors in an orthotopic rat liver tumor model. Poly(beta-amino ester) (PBAE) nanoparticles were formulated and assessed for GFP transfection in N1-S1 rat HCC cells in vitro. Optimized PBAE NPs were next administered to rats via intra-arterial injection with and without orthotopic HCC tumors, and both biodistribution and transfection were assessed. In vitro transfection of PBAE NPs led to >50% transfected cells in adherent and suspension culture at a variety of doses and weight ratios. Administration of NPs via intra-arterial or intravenous injection demonstrated no transfection of healthy liver, while intra-arterial NP injection led to transfection of tumors in an orthotopic rat HCC model. Hepatic artery injection is a promising delivery approach for PBAE NPs and demonstrates increased targeted transfection of HCC tumors compared to intravenous administration, and offers a potential alternative to standard chemotherapies and TACE. This work demonstrates proof of concept for administration of polymeric PBAE nanoparticles via intra-arterial injection for gene delivery in rats.

Abstract 2396: Longitudinal monitoring of stromal stiffness predicts immune escape in preclinical hepatocellular carcinoma

Abstract Background/Objectives: Increased tumor stiffness enhances disease progression and aggressiveness in several cancers. Stiffer extracellular tumor matrix hinders T cell trafficking and promotes immune escape. The interplay between liver tumor mechanical properties and hepatocellular immune cell landscape has not been fully investigated. The aim of our study is to correlate tumor stiffness quantified with shear wave elastography and tumor-infiltrating lymphocyte accumulation using a syngeneic orthotopic rat model of hepatocellular carcinoma (HCC). Methods: Rat hepatoma cell line McA-RH7777 were implanted in the left liver lobe of Buffalo rats. Maximum tumor size and stiffness were evaluated 3 weeks after implantation (baseline) and weekly for 14 days using ultrasound. The maximum tumor size of each rat was evaluated on transverse view of B-mode ultrasound. The elasticity of each rat was evaluated by shear wave elastography (SWE), and SWE measurements were obtained at the maximum tumor size in m/s. A circular region of interest was put manually on the SWE images to calculate tumor stiffness. SWE was performed 3 times for each rat at each time point, and the mean value of tumor stiffness was used for analysis. After 14 days, tumors were harvested for histology and immune cell isolation. Isolated cells were stained with CD3, CD4, CD8, CD25, CD45, CD103, CD161, CD279 (PD-1), FOXP3, IL17A, and INF-g and submitted to spectral cytometry. Results: Shear wave speed at baseline and at 14 days ranged from 1.95 to 3.07 m/s and from 2.25 to 3.26 m/s, respectively. The rate of longitudinal increase or decrease in tumor stiffness measured by SWE is inversely correlated with intratumoral infiltration of CD45+/CD3+, CD3+/CD8+ T cells and IFN-producing CD3+/CD8+ T cells (P=0.015, r=-0.62[-0.857, -0.15], P<0.01, r=-0.74[-0.913, -0.346], P=0.02, r=-0.6[-0.859, -0.107]). Intratumoral CD3+/CD4+ T cells did not significantly correlate with the rate of change in stiffness but did correlate with the rate of change in tumor size measured by B-mode ultrasound (P=0.03, r=-0.58[-0.850, -0.0730]). Conclusion: Our results confirm previous reports of immune escape in stiffer solid tumors in the context of HCC. Findings suggest that longitudinal monitoring of tumor stiffness can be useful for the assessment of immune cell infiltration. Citation Format: Kiyoyuki Minamiguchi, Andrea Cortes, Patricia Da Costa Lopez, Malea Williams, Simone Anfossi, Marites Melancon, Rony Avritscher. Longitudinal monitoring of stromal stiffness predicts immune escape in preclinical hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2396.

Overexpression of hepatic pescadillo 1 in obesity induces lipid dysregulation by inhibiting autophagy

Previous studies indicated that increased hepatic pescadillo 1 (PES1) in type II diabetic mice was associated with lipid dysregulation. However, the role of PES1 in obesity-associated lipid dysregulation is still unknown. This study investigates the effects and underlying mechanism. Livers from obese and healthy humans and mice were collected, and C57BL/6J mice were either fed on standard diet or high fat diet (HFD). McArdle 7777 rat hepatoma cells were treated with phosphate-buffered saline and oleic acid (OA)+ palmitic acid (PA), respectively. In vitro Pes1 knockdown or overexpression and in vivo Pes1 knockdown or liver-specific ablation or supplementation of Pes1 were used to explore the modulating role of PES1. We found that obesity in humans enhanced hepatic PES1 protein, accompanied by increased plasma TG. These data are consistent with those from OA+PA-treated cells and from HFD- or Pes1 overexpression-treated C57BL/6J mice. In vitro and in vivo Pes1 knockdown in cultured cells and in ob/ob mice promoted the expression of autophagy markers (TFEB, Beclin1 and LC3B-Ⅱ) while decreasing p62 and TG, contrary to Pes1 overexpression in cells and in normal mice. Moreover, liver-specific knockout of Pes1 protected the mice fed on HFD from increased TG levels, facilitating the TFEB, Beclin1 and LC3B-Ⅱ and curbing p62. Mechanistically, OA+PA increased C/EBPβ binding to the Pes1 promoter, leading to the elevation of PES1, and subsequently enhancing PES1-facilitated ubiquitination of TFEB. Our findings reveal that overexpression of hepatic PES1 in obesity may induce TG dysregulation by inhibiting autophagy.

A Comparison of Primary Human Hepatocytes and Hepatoma Cell Lines to Model the Effects of Fatty Acids, Fructose and Glucose on Liver Cell Lipid Accumulation.

Non-alcoholic fatty liver disease (NAFLD) begins with lipid accumulation within hepatocytes, but the relative contributions of different macronutrients is still unclear. We investigated the impact of fatty acids, glucose and fructose on lipid accumulation in primary human hepatocytes (PHH) and three different cell lines: HepG2 (human hepatoblastoma-derived cell line), Huh7 (human hepatocellular carcinoma cell line) and McA-RH7777 (McA, rat hepatocellular carcinoma cell line). Cells were treated for 48 h with fatty acids (0 or 200 μM), glucose (5 mM or 11 mM) and fructose (0 mM, 2 mM or 8 mM). Lipid accumulation was measured via Nile Red staining. All cell types accumulated lipid in response to fatty acids (p < 0.001). PHH and McA, but not HepG2 or Huh7 cells, accumulated more lipid with 11 mM glucose plus fatty acids (p = 0.004, fatty acid × glucose interaction, for both), but only PHH increased lipid accumulation in response to fructose (p < 0.001). Considerable variation was observed between PHH cells from different individuals. Lipid accumulation in PHH was increased by insulin (p = 0.003) with inter-individual variability. Similarly, insulin increased lipid accumulation in both HepG2 and McA cells, with a bigger response in McA in the presence of fatty acids (p < 0.001 for fatty acid × insulin). McA were more insulin sensitive than either HepG2 or Huh7 cells in terms of AKT phosphorylation (p < 0.001 insulin × cell type interaction). Hence, glucose and fructose can contribute to the accumulation of lipid in PHH with considerable inter-individual variation, but hepatoma cell lines are not good models of PHH.

Parthenolide induces rapid thiol oxidation that leads to ferroptosis in hepatocellular carcinoma cells.

Hepatocellular carcinoma (HCC) is both a devastating and common disease. Every year in the United States, about 24,500 men and 10,000 women are diagnosed with HCC, and more than half of those diagnosed patients die from this disease. Thus far, conventional therapeutics have not been successful for patients with HCC due to various underlying comorbidities. Poor survival rate and high incidence of recurrence after therapy indicate that the differences between the redox environments of normal surrounding liver and HCC are valuable targets to improve treatment efficacy. Parthenolide (PTL) is a naturally found therapeutic with anti-cancer and anti-inflammatory properties. PTL can alter HCC's antioxidant environment through thiol modifications leaving tumor cells sensitive to elevated reactive oxygen species (ROS). Investigating the link between altered thiol mechanism and increased sensitivity to iron-mediated lipid peroxidation will allow for improved treatment of HCC. HepG2 (human) and McARH7777 (rat) HCC cells treated with PTL with increasing concentrations decrease cell viability and clonogenic efficiency in vitro. PTL increases glutathione (GSH) oxidation rescued by the addition of a GSH precursor, N-acetylcysteine (NAC). In addition, this elevation in thiol oxidation results in an overall increase in mitochondrial dysfunction. To elucidate if cell death is through lipid peroxidation, using a lipid peroxidation sensor indicated PTL increases lipid oxidation levels after 6h. Additionally, western blotting reveals glutathione peroxidase 4 (GPx4) protein levels decrease after treatment with PTL suggesting cells are incapable of preventing lipid peroxidation after exposure to PTL. An elevation in lipid peroxidation will lead to a form of cell death known as ferroptosis. To further establish ferroptosis as a critical mechanism of death for HCC in vitro, the addition of ferrostatin-1 combined with PTL demonstrates a partial recovery in a colony survival assay. This study reveals that PTL can induce tumor cell death through elevations in intracellular oxidation, leaving cells sensitive to ferroptosis.

Platelet-Derived Microvesicles Promote Selective Cell Viability in Hepatocellular Carcinoma: Differences in Properties between Normal Platelets and Tumor Educated Platelets

Tumor cells educate platelets by modulating their RNA profiles and phenotypes. These platelets are termed "tumor educated platelets: TEPs", and this concept is widely accepted. We have previously reported that platelets are activated in microvessels within liver tumors, leading to the progression of hepatocellular carcinoma (HCC). When platelets are activated, platelet-derived microvesicles (PDMV) containing platelet-derived nucleic acids and proteins are released. The contents in these are known to vary depending on the various pathological conditions of the host. It is generally believed that when cells take up extracellular vesicles, they are affected by the action of the encapsulated substances. However, it is still unclear what biological properties of PDMV are released by TEPs and how they are involved in carcinogenesis. We hypothesized that the release of PDMV by activated platelets in liver tissue and the uptake of its contents by normal hepatocytes and HCC cells may be involved in the progression of hepatocarcinogenesis, and we analyzed their role in carcinogenesis. The rat HCC model was prepared according to the Solt-Farber protocol. Briefly, male F344 rats were injected intraperitoneally with diethylnitrosamine at 4 weeks of age, then fed a powdered diet containing 2-acetylaminofluorene to induce liver damage, followed by partial hepatectomy. The rats were then kept under normal conditions for more than one month. Abdominal ultrasonography was performed on rats, and those with obvious tumors with a diameter of 2 mm or more were used for the experiments. Peripheral blood was collected from the tail veins of normal rats or HCC model rats, and platelets were isolated. The platelets were labeled with the fluorescent substance CMRA, activated in vitro with thrombin, and the PDMV in the supernatant was collected by polyethylene glycol precipitation and used as CMRA-labeled PDMV in the experiments. When PDMV was added to primary cultured rat hepatocytes and cultured for 24 hours, fluorescence was observed in the hepatocytes. The fluorescence was also observed in hepatocytes in the portal region of liver tissue collected 24 hours after injection of CMRA-labeled PDMV from the mesenteric vein of rats. These indicate that PDMV released into the liver tissue is taken up by hepatocytes. Peripheral blood platelets from normal rats or HCC model rats were isolated and PDMV was purified from each (N-PDMV and HCC-PDMV). These PDMVs were added to cultures of normal rat hepatocytes and hepatocellular carcinoma cell lines to analyze their effects on cell survival. N-PDMV did not affect the viability of normal hepatocytes, but mildly enhanced the survival of HCC cells. On the other hand, HCC-PDMV inhibited the viability of normal hepatocytes, but promoted viability of HCC cells more strongly than N-PDMV. These results indicate that the contents of PDMV differ between normal and HCC rats, and in particular that PDMV from rats with HCC is taken up by normal and HCC cells and is associated with selective survival of HCC cells.

Fabrication of a Tailored, Hybrid Extracellular Matrix Composite

The extracellular matrix (ECM) is a network of connective fibers that supports cells living in their surroundings. Native ECM, generated by the secretory products of each tissue's resident cells, has a unique architecture with different protein composition depending on the tissue. Therefore, it is very difficult to artificially design in vivo architecture in tissue engineering. In this study, a hybrid ECM scaffold from the basic structure of fibroblast-derived cellular ECMs is fabricated by adding major ECM components of fibronectin (FN) and collagen (COL I) externally. It is confirmed that while maintaining the basic structure of the native ECM, major protein components can be regulated. Then, decellularization is performed to prepare hybrid ECM scaffolds with various protein compositions and it is demonstrated that a liver-mimicking fibronectin (FN)-rich hybrid ECM promoted successful settling of H4IIE rat hepatoma cells. The authors believe that their method holds promise for the fabrication of scaffolds that provide a tailored cellular microenvironment for specific organs and serve as novel pathways for the replacement or regeneration of specific organ tissues.

Effect of Acrylamide Treatment on Cyp2e1 Expression and Redox Status in Rat Hepatocytes.

Acrylamide (AA) toxicity is associated with oxidative stress. During detoxification, AA is either coupled to gluthatione or biotransformed to glycidamide by the enzyme cytochrome P450 2E1 (CYP2E1). The aim of our study was to examine the hepatotoxicity of AA in vivo and in vitro. Thirty male Wistar rats were treated with 25 or 50 mg/kg b.w. of AA for 3 weeks. Qualitative and quantitative immunohistochemical evaluation of inducible nitric oxide synthase (iNOS), CYP2E1, catalase (CAT), superoxide dismutase 1 (SOD1), and SOD2 expression in liver was carried out. Bearing in mind that the liver is consisted mainly of hepatocytes, in a parallel study, we used the rat hepatoma cell line H4IIE to investigate the effects of AA at IC20 and IC50 concentrations on the redox status and the activity of CAT, SOD, and glutathione-S-transferase (GST), their gene expression, and CYP2E1 and iNOS expression. Immunohistochemically stained liver sections showed that treatment with AA25mg induced a significant decrease of CYP2E1 protein expression (p < 0.05), while treatment with AA50mg led to a significant increase of iNOS protein expression (p < 0.05). AA treatment dose-dependently elevated SOD2 protein expression (p < 0.05), while SOD1 protein expression was significantly increased only at AA50mg (p < 0.05). CAT protein expression was not significantly affected by AA treatments (p > 0.05). In AA-treated H4IIE cells, a concentration-dependent significant increase in lipid peroxidation and nitrite levels was observed (p < 0.05), while GSH content and SOD activity significantly decreased in a concentration-dependent manner (p < 0.05). AA IC50 significantly enhanced GST activity (p < 0.05). The level of mRNA significantly increased in a concentration-dependent manner for iNOS, SOD2, and CAT in AA-treated H4IIE cells (p < 0.05). AA IC50 significantly increased the transcription of SOD1, GSTA2, and GSTP1 genes (p < 0.05), while AA IC20 significantly decreased mRNA for CYP2E1 in H4IIE cells (p < 0.05). Obtained results indicate that AA treatments, both in vivo and in vitro, change hepatocytes; drug-metabolizing potential and disturb its redox status.

Neutralization and receptor use of infectious culture-derived rat hepacivirus as a model for HCV.

Lack of tractable immunocompetent animal models amenable to robust experimental challenge impedes vaccine efforts for HCV. Infection with rodent hepacivirus from Rattus norvegicus (RHV-rn1) in rats shares HCV-defining characteristics, including liver tropism, chronicity, and pathology. RHV in vitro cultivation would facilitate genetic studies on particle production, host factor interactions, and evaluation of antibody neutralization guiding HCV vaccine approaches. We report an infectious reverse genetic cell culture system for RHV-rn1 using highly permissive rat hepatoma cells and adaptive mutations in the E2, NS4B, and NS5A viral proteins. Cell culture-derived RHV-rn1 particles (RHVcc) share hallmark biophysical characteristics of HCV and are infectious in mice and rats. Culture adaptive mutations attenuated RHVcc in immunocompetent rats, and the mutations reverted following prolonged infection, but not in severe combined immunodeficiency (SCID) mice, suggesting that adaptive immune pressure is a primary driver of reversion. Accordingly, sera from RHVcc-infected SCID mice or the early acute phase of immunocompetent mice and rats were infectious in culture. We further established an in vitro RHVcc neutralization assay, and observed neutralizing activity of rat sera specifically from the chronic phase of infection. Finally, we found that scavenger receptor class B type I promoted RHV-rn1 entry in vitro and in vivo. The RHV-rn1 infectious cell culture system enables studies of humoral immune responses against hepacivirus infection. Moreover, recapitulation of the entire RHV-rn1 infectious cycle in cell culture will facilitate reverse genetic studies and the exploration of tropism and virus-host interactions.