A novel G418 conjugate results in targeted selection of genetically protected hepatocytes without bystander toxicity

Liraglutide Exerts Protective Effects by Downregulation of PPARγ, ACSL1 and SREBP-1c in Huh7 Cell Culture Models of Non-Alcoholic Steatosis and Drug-Induced Steatosis

(1) Background: With the aging of the population and polypharmacy encountered in the elderly, drug-induced steatosis (DIS) has become frequent cause of non-alcoholic steatosis (NAS). Indeed, NAS and DIS may co-exist, making the ability to distinguish between the entities ever more important. The aim of our study was to study cell culture models of NAS and DIS and determine the effects of liraglutide (LIRA) in those models. (2) Methods: Huh7 cells were treated with oleic acid (OA), or amiodarone (AMD) to establish models of NAS and DIS, respectively. Cells were treated with LIRA and cell viability was assessed by MTT, lipid accumulation by Oil-Red-O staining and triglyceride assay, and intracellular signals involved in hepatosteatosis were quantitated by RT-PCR. (3) Results: After exposure to various OA and AMD concentrations, those that achieved 80% of cells viabilities were used in further experiments to establish NAS and DIS models using 0.5 mM OA and 20 µM AMD, respectively. In both models, LIRA increased cell viability (p < 0.01). Lipid accumulation was increased in both models, with microsteatotic pattern in DIS, and macrosteatotic pattern in NAS which corresponds to greater triglyceride accumulation in latter. LIRA ameliorated these changes (p < 0.001), and downregulated expression of lipogenic ACSL1, PPARγ, and SREBP-1c pathways in the liver (p < 0.01) (4) Conclusions: LIRA ameliorates hepatocyte steatosis in Huh7 cell culture models of NAS and DIS.

Pretreatment of Garlic Oil Extracts Hampers Epithelial Damage in Cell Culture Model of Peptic Ulcer Disease

Background and Objectives: Peptic ulcer disease is a chronic disease affecting up to 10% of the world’s population. Proton pump inhibitors, such as lansoprazole are the gold standard in the treatment of ulcer disease. However, various studies have shown the effectiveness of garlic oil extracts in the treatment of ulcer disease. A cellular model can be established in the human gastric cell line by sodium taurocholate. The aim of this study was to explore the effects of garlic oil extracts pretreatment and LPZ addition in the cell culture model of peptic ulcer disease by examining oxidative stress and F-actin distribution. Materials and Methods: Evaluation was performed by determination of glutathione and prostaglandin E2 concentrations by ELISA; human gastric cell line proliferation by cell counting; expression of ATP-binding cassette, sub-family G, member 2; nuclear factor kappa B subunit 2 by RT PCR; and F-actin cytoskeleton visualization by semi-quantification of Rhodamine Phalloidin stain. Results: Our results showed significant reduction of cell damage after sodium taurocholate incubation when the gastric cells were pretreated with lansoprazole (p < 0.001) and increasing concentrations of garlic oil extracts (p < 0.001). Pretreatment with lansoprazole and different concentrations of garlic oil extracts increased prostaglandin E2 and glutathione concentrations in the cell culture model of peptic ulcer disease (p < 0.001). Positive correlation of nuclear factor kappa B subunit 2 (p < 0.01) with lansoprazole and garlic oil extracts pretreatment was seen, while ATP-binding cassette, sub-family G, member 2 expression was not changed. Treatment with sodium taurocholate as oxidative stress on F actin structure was less pronounced, although the highest concentration of garlic oil extracts led to a statistically significant increase of total amount of F-actin (p < 0.001). Conclusions: Hence, pretreatment with garlic oil extracts had gastroprotective effect in the cell model of peptic ulcer disease. However, further experiments are needed to fully elucidate the mechanism of this protective role.

Pharmacogenetic selection of transplanted human hepatocytes in immunocompetent rats

OBJECTIVE

To introduce a genetic survival advantage for transplanted human hepatocytes over host cells in rats.

METHODS

Green fluorescent protein (GFP) was introduced into Huh-7 human hepatoma cells to create fluorescent GFP-Huh-7 cells. mRNA of CYP2E1, the enzyme that converts acetaminophen (APA) into hepatotoxic intermediates, was quantified by real-time polymerase chain reaction (PCR). The effects of APA on GFP-Huh-7 and control Huh-7 cells were determined in a cell culture. Immunological tolerance was induced by the injection of GFP-Huh-7 cells into fetal rats in utero. The GFP-Huh-7 cells were transplanted after birth of the rats into tolerant rats followed by APA treatment. Serum alanine aminotransferase (ALT) levels and liver histological data were obtained. GFP-Huh-7 cells were detected by quantitive PCR and microscopy.

RESULTS

CYP2E1 mRNA levels in the GFP-Huh-7 cells were 2.7% of parental Huh-7 cells. In 1 mmol/L APA, parental Huh-7 cells decreased by 60% while GFP-Huh-7 cells increased to within 95% of untreated controls after 5 days. In rats in which GFP-Huh-7 cells were transplanted and treated with APA, serum ALT increased to a peak of 200 U/L on day 1 and returned to normal levels by day 3. Fluorescence microscopy of liver specimens from rats transplanted with GFP-Huh-7 cells showed substantial increases in GFP-Huh-7, but not Huh-7 cells by day 7 after APA treatment. Real-time PCR confirmed a 10-fold increase of GFP mRNA in APA-treated rats, but not in those without APA treatment.

CONCLUSIONS

The difference in CYP2E1 gene expression between GFP-Huh-7 and rat hepatocytes provides a convenient means for the enrichment of transplanted human cells in rat liver.