Center for Phytochemical Epigenome Studies, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States.
Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, United States.
Chem Res Toxicol. 2021 Mar 15;34(3):713-722. doi: 10.1021/acs.chemrestox.0c00235. Epub 2021 Jan 15.
Diabetic nephropathy (DN) is the major cause of kidney related diseases in patients induced by high glucose (HG) affecting around 40% of type 1 and 2 diabetic patients. It is characterized by excessive inflammation inducing factors, reactive oxygen species (ROS) overproduction, and potential epigenomic related changes. Fucoxanthin (FX), a carotenoid found in brown seaweed, has a structure which includes an allenic bond and a 5,6-monoepoxide in the molecule, with strong antioxidant and anti-inflammatory activity. However, understanding of the impact of FX on DN was lacking. In this study we tested the early effects of high glucose (HG) on mouse mesangial kidney Mes13 cells, a potential cell culture model of DN. Our results show that HG induced oxidative stress on kidney mesangial Mes13 cells, while FX treatment attenuates the oxidative stress by decreasing the ROS, demonstrated by flow cytometry. Next, we utilized next-generation sequencing (NGS) to profile the HG-induced early epigenomic and transcriptomic changes in this DN model and the protective effects of FX. Differentially expressed genes (DEGs) and differentially methylated regions (DMRs) were analyzed using R software in HG and FX treated groups. Differential regulation of signaling pathways was studied using Reactome Pathway Analysis in the comparison. DEG analysis shows that novel biomarkers with specific pathways, including interleukin regulation, Toll-like receptor pathway, and PKA phosphorylation pathways, were found to be modulated by the FX treatment. TGF β 1i1 (TGFB 1i1), MAP-3-kinase-13(MAP3K13) involved in crucial cellular processes including glucose metabolism, phosphodiesterase regulation was methylated in HG, which was demethylated with FX treatment. Integrated transcriptomic and CpG methylome analysis of DEGs and DMRs revealed that genes like adenylate cyclase (Adcy7), calponin 1 (CNN1), potassium voltage-gated channel interacting protein 2 (KCNIP2), phosphatidylinositol-4-phosphate 5-kinase type 1 β (PIP5K1B), and transmembrane protein with EGF-like and two follistatin-like domains 1 (TMEFF1), which were modulated by FX in HG-exposed Mes13 cells, potentially modulate ion channel transport and glucose metabolism. In summary, our current study shows that novel early epigenomic and transcriptomic biomarkers were altered during the disease progression of HG-induced DN and that FX modified these alterations potentially contributing to the protective effects of mesangial cells from the HG-induced oxidative stress and damage.
糖尿病肾病（DN）是高血糖（HG）引起的肾脏相关疾病的主要原因，约占 1 型和 2 型糖尿病患者的 40%。其特征是过度炎症诱导因子、活性氧（ROS）产生过多和潜在的表观基因组相关变化。岩藻黄质（FX）是一种在褐藻中发现的类胡萝卜素，其分子中包含一个烯丙基键和一个 5,6-单环氧，具有很强的抗氧化和抗炎活性。然而，FX 对 DN 的影响尚不清楚。在这项研究中，我们测试了高葡萄糖（HG）对小鼠系膜肾 Mes13 细胞的早期影响，Mes13 细胞是一种潜在的糖尿病肾病细胞培养模型。我们的结果表明，HG 诱导肾系膜 Mes13 细胞发生氧化应激，而 FX 处理通过流式细胞术减少 ROS 来减轻氧化应激。接下来，我们利用下一代测序（NGS）来描绘这个糖尿病肾病模型中 HG 诱导的早期表观基因组和转录组变化，以及 FX 的保护作用。在 HG 和 FX 处理组中，使用 R 软件分析差异表达基因（DEG）和差异甲基化区域（DMR）。在比较中，使用 Reactome 途径分析研究信号通路的差异调节。DEG 分析表明，FX 处理调节了包括白细胞介素调节、Toll 样受体途径和 PKA 磷酸化途径在内的具有特定途径的新型生物标志物。TGFB1i1（TGFB1i1）和 MAP3-kinase-13（MAP3K13）是参与葡萄糖代谢、磷酸二酯酶调节等关键细胞过程的基因，在 HG 中发生甲基化，在 FX 处理下被去甲基化。对 DEG 和 DMR 的转录组和 CpG 甲基组分析表明，FX 在 HG 暴露的 Mes13 细胞中调节的基因，如腺苷酸环化酶（Adcy7）、钙调蛋白 1（CNN1）、钾电压门控通道相互作用蛋白 2（KCNIP2）、磷酸肌醇-4-磷酸 5-激酶 1β（PIP5K1B）和跨膜蛋白与表皮生长因子样和两个卵泡抑素样结构域 1（TMEFF1），可能调节离子通道转运和葡萄糖代谢。总之，我们的研究表明，在 HG 诱导的糖尿病肾病的疾病进展过程中，新型早期表观基因组和转录组生物标志物发生改变，而 FX 改变了这些改变，可能有助于系膜细胞免受 HG 诱导的氧化应激和损伤的保护作用。
