Related Experiment Videos
Exploring Chronic Drug Effects on Microengineered Human Liver Cultures Using Global Gene Expression Profiling.
Brenton R Ware1,2, Michael McVay3, Wendy Y Sunada1,4
1School of Biomedical Engineering, Colorado State University, Fort Collins, Colorado, USA.
Summary
Micropatterned cocultures (MPCCs) of primary human hepatocytes (PHHs) reveal distinct gene expression patterns for hepatotoxic drugs. This model predicts drug-induced liver injury by analyzing chronic drug treatment effects on gene expression.
Area of Science:
- Hepatology and Toxicology
- Genomics and Transcriptomics
- Drug Discovery and Development
Background:
- Global gene expression profiling aids in understanding drug mechanisms but faces limitations in predicting human liver injury using rat models.
- Primary human hepatocytes (PHHs) in traditional monolayer cultures dedifferentiate, limiting chronic drug exposure studies.
- Micropatterned cocultures (MPCCs) of PHHs and fibroblasts maintain a stable liver phenotype for extended periods (4-6 weeks).
Purpose of the Study:
- To test the hypothesis that gene expression patterns in stable PHHs within MPCCs can differentiate clinical hepatotoxic drugs from non-toxic analogs.
- To understand the mechanism of action of hepatotoxic drugs before overt liver injury occurs.
- To evaluate time- and dose-dependent gene expression changes in PHHs under chronic analog drug treatment.
Main Methods:
- Utilized MPCCs containing PHH colonies and 3T3-J2 fibroblasts to culture stable primary human hepatocytes.
- Treated MPCCs with clinical hepatotoxic/non-liver-toxic drug pairs (troglitazone/rosiglitazone, nefazodone/buspirone, ibufenac/ibuprofen, tolcapone/entacapone) at various doses and time points (1, 7, 14 days).
- Analyzed global gene expression profiles using differential gene expression analysis relative to vehicle-treated controls.
Main Results:
- Troglitazone (hepatotoxin) modulated significantly more genes (12, 269, 628 at 1, 7, 14 days) than rosiglitazone (analog) in MPCCs.
- Troglitazone affected key pathways including fatty acid metabolism, drug metabolism, oxidative stress, and inflammation.
- Other hepatotoxins consistently induced greater gene expression changes than their non-liver-toxic analogs after 7 days of treatment.
Conclusions:
- MPCCs provide a robust model for chronic drug treatment and gene expression analysis in stable PHHs.
- Global gene expression profiling in MPCCs can distinguish hepatotoxic from non-hepatotoxic drugs and elucidate mechanisms of liver injury.
- This approach enables early prediction of drug-induced liver injury and mechanism of action prior to clinical manifestation.