Department of Chemistry, University of North Carolina at Chapel Hill, Kenan and Caudill Laboratories, Chapel Hill, NC 27599-3290, United States of America.
Department of Chemistry, University of North Carolina at Chapel Hill, Kenan and Caudill Laboratories, Chapel Hill, NC 27599-3290, United States of America; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, 450 West Drive, Chapel Hill, NC 27599-7295, United States of America.
Toxicol In Vitro. 2021 Aug;74:105156. doi: 10.1016/j.tiv.2021.105156. Epub 2021 Mar 31.
This study evaluates the impact of physiologically relevant oxygen tensions on the response of HepG2 cells to known inducers and hepatotoxic drugs. We compared transcriptional regulation and CYP1A activity after a 48 h exposure at atmospheric culture conditions (20% O) with representative periportal (8% O) and perivenous (3% O) oxygen tensions. We evaluated cellular responses in 2D and 3D cultures at each oxygen tension in parallel, using monolayers and a paper-based culture platform that supports cells suspended in a collagen-rich environment. Our findings highlight that the toxicity, potency, and mechanism of action of drugs are dependent on both culture format and oxygen tension. HepG2 cells in 3D environments at physiologic oxygen tensions better matched primary human hepatocyte data than HepG2 cells cultured under standard conditions. Despite altered transcriptional regulation with decreasing oxygen tensions, we did not observe the zonation patterns of drug-metabolizing enzymes found in vivo. Our approach demonstrates that oxygen is an important regulator of liver function but it is not the sole regulator. It also highlights the utility of the 3D paper-based culture platform for continued mechanistic studies of microenvironmental influences on cellular responses.
本研究评估了生理相关氧张力对 HepG2 细胞对已知诱导剂和肝毒性药物反应的影响。我们比较了在大气培养条件（20% O）下暴露 48 小时后，代表性门脉周（8% O）和门静脉周（3% O）氧张力下的转录调控和 CYP1A 活性。我们在每种氧张力下平行评估了 2D 和 3D 培养物中的细胞反应，使用单层和支持在富含胶原蛋白的环境中悬浮的细胞的基于纸张的培养平台。我们的研究结果表明，药物的毒性、效力和作用机制取决于培养方式和氧张力。在生理氧张力下的 3D 环境中的 HepG2 细胞比在标准条件下培养的 HepG2 细胞更能匹配原代人肝细胞数据。尽管随着氧张力的降低转录调控发生改变，但我们没有观察到体内存在的药物代谢酶的分区模式。我们的方法表明，氧是肝脏功能的重要调节剂，但不是唯一的调节剂。它还突出了基于纸张的 3D 培养平台在继续研究微环境对细胞反应的影响的机制研究方面的实用性。
