Background

Berberine has been shown in clinical studies to have many health benefits, including anti-inflammatory and antioxidant properties, along with gut-flora balancing properties. However, its clinical efficacy is hindered by its low oral bioavailability and rapid metabolism.

Purpose

This study aims to identify the berberine metabolites' forms and characterize their biodistribution patterns in and out of HepG2 cells.

Methods

The qualitative analysis of metabolites of berberine in HepG2 cells was performed using the LC/MSⁿ-IT-TOF method. Subsequent cellular pharmacokinetics characterization of intracellular and extracellular berberine and its metabolites was performed by LC-MS/MS analysis.

Results

Berberine's metabolites of phase I metabolism were demethyleneberberine, jatrorrhizine, columbamine, berberrubine, etc., while its phase II metabolites were sulfate and glucuronide conjugates of phase I metabolites. Among the phase I metabolites of berberine, jatrorrhizine+columbamine accounted for over two-thirds of the total, followed by demethyleneberberine, which accounted for about a quarter. The intracellular demethyleneberberine is 25.14 times more enriched than extracellular demethyleneberberine. On the other hand, jatrorrhizine+columbamine and berberrubine were primarily distributed extracellularly, and their extracellular concentrations were 7.13 times and 15.61 times of their intracellular concentrations, respectively. Berberine metabolites produced in phase II metabolism are predominantly sulfate conjugates.

Conclusion

Our results show that demethyleneberberine is highly concentrated intracellularly in HepG2, possibly because it is an essential metabolite of berberine that likely contributes to berberine's efficacy. In light of our findings, berberine's poor plasma concentration-effectiveness characteristics have been partially explained.

中文翻译：

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黄连素及其代谢物在肝细胞中的生物分布和药代动力学特征

背景

临床研究表明，小檗碱具有许多健康益处，包括抗炎和抗氧化特性，以及肠道菌群平衡特性。然而，其临床疗效受到其低口服生物利用度和快速代谢的阻碍。

目的

本研究旨在鉴定小檗碱代谢物的形式并表征其在 HepG2 细胞内外的生物分布模式。

方法

使用 LC/MS ⁿ -IT-TOF 方法对 HepG2 细胞中的黄连素代谢物进行定性分析。随后通过 LC-MS/MS 分析进行细胞内和细胞外黄连素及其代谢物的细胞药代动力学表征。

结果

小檗碱的Ⅰ期代谢产物为脱亚甲基小檗碱、药根碱、哥伦布明、小檗红碱等，Ⅱ期代谢产物为Ⅰ期代谢产物的硫酸盐和葡糖苷酸结合物。在小檗碱的Ⅰ期代谢产物中，药根碱+昆布明占总量的三分之二以上，其次是脱亚甲基小檗碱，约占四分之一。细胞内去亚甲基小檗碱的含量是细胞外去亚甲基小檗碱的 25.14 倍。另一方面，药根碱+哥伦比亚明珠和小檗红碱主要分布在细胞外，其细胞外浓度分别是细胞内浓度的7.13倍和15.61倍。在 II 期代谢中产生的小檗碱代谢物主要是硫酸盐结合物。

结论

我们的研究结果表明，脱亚甲基小檗碱在 HepG2 细胞内高度浓缩，这可能是因为它是小檗碱的必需代谢物，可能有助于小檗碱的功效。根据我们的研究结果，部分解释了小檗碱较差的血浆浓度-有效性特征。