Wei Jiaojun, Xia Tian, Chen Weijia, Ran Pan, Chen Maohua, Li Xiaohong
Key Laboratory of Advanced Technologies of Materials, Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, China.
School of Bioscience and Technology, Chengdu Medical College, Chengdu, China.
J Tissue Eng Regen Med. 2020 Jun;14(6):774-788. doi: 10.1002/term.3042. Epub 2020 Apr 19.
With the rise of obesity, diabetes, and other metabolic diseases, in vitro hepatic cell and tissue models play an essential role in the identification of active pharmaceutical ingredients. Up to now, three-dimensional (3D) culture models have rarely focused on hepatic glucose and lipid metabolism. In addition, primary human liver cells suffer from limited availability and interdonor difference for establishing reproducible models. Thus, in the current study, the most available human liver cancer cell line (HepG2) and primary hepatocytes from rats (rPH) were proposed to construct 3D spheroids using injectable fiber fragments with galactose grafts (gSF) as the substrate. rPH and HepG2 spheroids show strong cell-cell and cell-fiber fragment interactions to promote the cell viability, albumin, and urea syntheses. Compared with HepG2 spheroids, rPH spheroids indicate stronger glucose metabolism abilities in terms of glucose consumption, intracellular glycogen content, gluconeogenesis rate, and sensitivity to glucose modulator hormones like insulin and glucagon. On the other hand, HepG2 spheroids display strong lipid metabolism abilities in producing significantly higher levels of total cholesterol and triglyceride. Compared with those without fiber fragments, the gSF-supported 3D culture establishes effective models for in vitro glucose (rPH spheroids) and lipid metabolisms (HepG2 spheroids). The screening models are confirmed from the respective enzyme activities and gene expressions and show significantly higher sensitivity and clinically related responses to hypoglycemic and lipid-lowering drugs. Thus, the culture configuration demonstrates a predictable in vitro platform for defining glucose and lipid metabolism profiles and screening therapeutic agents for metabolism disorders like diabetes and obesity.
随着肥胖症、糖尿病和其他代谢性疾病的增多，体外肝细胞和组织模型在活性药物成分的鉴定中发挥着重要作用。到目前为止，三维（3D）培养模型很少关注肝脏葡萄糖和脂质代谢。此外，原代人肝细胞在建立可重复模型时存在可用性有限和供体间差异的问题。因此，在本研究中，提出使用具有半乳糖接枝的可注射纤维片段（gSF）作为底物，构建最易获得的人肝癌细胞系（HepG2）和大鼠原代肝细胞（rPH）的3D球体。rPH和HepG2球体显示出强大的细胞-细胞和细胞-纤维片段相互作用，以促进细胞活力、白蛋白和尿素合成。与HepG2球体相比，rPH球体在葡萄糖消耗、细胞内糖原含量、糖异生率以及对胰岛素和胰高血糖素等葡萄糖调节激素的敏感性方面表现出更强的葡萄糖代谢能力。另一方面，HepG2球体在产生显著更高水平的总胆固醇和甘油三酯方面显示出强大的脂质代谢能力。与没有纤维片段的情况相比，gSF支持的3D培养建立了体外葡萄糖（rPH球体）和脂质代谢（HepG2球体）的有效模型。筛选模型通过各自的酶活性和基因表达得到证实，并对降糖和降脂药物表现出显著更高的敏感性和临床相关反应。因此，这种培养结构展示了一个可预测的体外平台，用于定义葡萄糖和脂质代谢谱以及筛选糖尿病和肥胖症等代谢紊乱的治疗药物。
