Abstract：
Berberrubine (BRB), a main metabolite of berberine, has stronger hypoglycemic and lipid-lowering activity than its parent form. We previously found that BRB could cause obvious nephrotoxicity, but the molecular mechanism involved remains unknown. In this study, we systematically integrated metabolomics and quantitative proteomics to reveal the potential mechanism of nephrotoxicity caused by BRB. Metabolomic analysis revealed that 103 significant- differentially metabolites were changed. Among the mentioned compounds, significantly upregulated metabolites were observed for phosphorylcholine, sn-glycerol-3-phosphoethanolamine, and phosphatidylcholine. The top three enriched KEGG pathways were the mTOR signaling pathway, central carbon metabolism in cancer, and choline metabolism in cancer. ERK1/2 plays key roles in all three metabolic pathways. To further confirm the main signaling pathways involved, a proteomic analysis was conducted to screen for key proteins (such as Mapk1, Mapk14, and Caspase), indicating the potential involvement of cellular growth and apoptosis. Moreover, combined metabolomics and proteomics analyses revealed the participation of ERK1/2 in multiple metabolic pathways. These findings indicated that ERK1/2 regulated the significant- differentially abundant metabolites determined via metabolomics analysis. Notably, through a cellular thermal shift assay (CETSA) and molecular docking, ERK1/2 were revealed to be the direct binding target involved in BRB-induced nephrotoxicity. To summarize, this study sheds light on the understanding of severe nephrotoxicity caused by BRB and provides scientific basis for its safe use and rational development.
摘要：
小柏鲁宾（BRB），小檗碱的主要代谢产物,具有比其母体形式更强的降血糖和降脂活性。我们以前发现BRB可以引起明显的肾毒性，但是所涉及的分子机制仍然未知。在这项研究中,我们系统地整合代谢组学和定量蛋白质组学，以揭示BRB引起肾毒性的潜在机制。代谢组学分析显示，有103个显着的差异代谢物发生了变化。在上述化合物中，观察到磷酸胆碱的代谢产物显着上调，sn-甘油-3-磷酸乙醇胺，和磷脂酰胆碱.前三个富集的KEGG通路是mTOR信号通路,癌症的中心碳代谢，和癌症中的胆碱代谢。ERK1/2在所有三种代谢途径中起关键作用。为了进一步确认所涉及的主要信号通路，进行蛋白质组学分析以筛选关键蛋白质（例如Mapk1，Mapk14和Caspase），表明细胞生长和凋亡的潜在参与。此外，联合代谢组学和蛋白质组学分析显示,ERK1/2参与多种代谢途径.这些发现表明ERK1/2调节通过代谢组学分析确定的显著差异丰富的代谢物。值得注意的是,通过细胞热转移测定（CETSA）和分子对接，发现ERK1/2是BRB诱导的肾毒性的直接结合靶标。总结一下,本研究为了解BRB引起的严重肾毒性提供了依据，为其安全使用和合理开发提供了科学依据。
