Department of Pharmaceutical Analysis, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, PR China.
Department of Metabolomics, Jiangsu Province Academy of Traditional Chinese Medicine, Nanjing 210028, PR China.
J Chromatogr B Analyt Technol Biomed Life Sci. 2023 Jul 15;1226:123806. doi: 10.1016/j.jchromb.2023.123806. Epub 2023 Jun 17.
Cicadae Periostracum (CP), the slough molted from the nymph of Cryptotympana pustulata, is a widely used medicinal material in traditional Chinese medicine (TCM). N-acetyldopamine oligomers (NAOs), the homologues of acetyldopamine, including N-acetyldopamine dimers/trimers/tetramers/pentamers (NADs/NATrs/NATes/NAPs), side-chain isomer of dimers/trimers (SCIDs/SCITrs), are major bioactive ingredients of CP. However, owing to commercially unavailable reference substances of all NAOs, simultaneous quantification of these NAOs in biological samples is difficult, and thus their pharmacokinetics are still unknown. In this study, a comprehensive strategy for simultaneous quantification/semi-quantification of NAOs in plasma with single N-acetyldopamine dimer A (NAD-A) as reference substance was established and comparatively investigated their pharmacokinetics after oral administration of pure NAD-A and two types of CP extracts, i.e., post-molting-washed slough (CP-WAT) and pre-molting-washed slough (CP-WBT). A UPLC-QTOF-MS/MS assisted UPLC-TQ-MS/MS strategy was developed to quantify NAOs in rat plasma. NAOs in CP extract were qualitatively characterized by UPLC-QTOF-MS/MS, then the quasi-molecular ions and characteristic fragment ions of the identified NAOs by UPLC-QTOF-MS/MS were transferred to UPLC-TQ-MS/MS as parent-daughter ion pairs for MRM mode quantification of the NAOs, and the method was validated with single NAD-A for quantifying NAD-A and semi-quantifying other NAOs in plasma. The established method was applied to compare the pharmacokinetics of NAOs after oral administration of NAD-A and the extracts of CP-WBT/CP-WAT respectively. Six quasi-molecular ions and characteristic fragment ion m/z 192.1 were characterized by UPLC-QTOF-MS/MS and transferred to be the parent-daughter ion pairs for UPLC-TQ-MS/MS analysis of six kinds of NAOs. For the pharmacokinetics, NAD-A showed double peaks absorption character when administered with single compound, but with higher relative bioavailability when administered with CP extracts with the similar dosage. Compared with CP-WAT, NAOs in CP-WBT reached the maximum plasma concentration in much shorter time.
蝉蜕（CP）是黑蚱蝉若虫蜕皮后的外壳，是一种广泛应用于中药（TCM）的药材。N-乙酰多巴胺低聚物（NAOs）是乙酰多巴胺的同系物，包括 N-乙酰多巴胺二聚体/三聚体/四聚体/五聚体（NADs/NATrs/NATes/NAPs）、二聚体/三聚体的侧链异构体（SCIDs/SCITrs），是 CP 的主要生物活性成分。然而，由于所有 NAOs 的商业上不可用的参考物质，对生物样品中这些 NAOs 的同时定量分析较为困难，因此其药代动力学仍然未知。在这项研究中，建立了一种以单一 N-乙酰多巴胺二聚体 A（NAD-A）作为参考物质同时定量/半定量分析 NAOs 的综合策略，并比较了口服纯 NAD-A 和两种 CP 提取物（即蜕皮后洗涤的蜕（CP-WAT）和蜕皮前洗涤的蜕（CP-WBT）后，NAOs 的药代动力学。采用 UPLC-QTOF-MS/MS 辅助 UPLC-TQ-MS/MS 策略定量分析大鼠血浆中的 NAOs。采用 UPLC-QTOF-MS/MS 对 CP 提取物中的 NAOs 进行定性分析，然后将 UPLC-QTOF-MS/MS 鉴定的 NAOs 的准分子离子和特征碎片离子转移到 UPLC-TQ-MS/MS 中，作为母-子离子对，采用单 NAD-A 进行定量分析，采用半定量分析其他 NAOs 在血浆中的含量。该方法用于比较 NAD-A 和 CP-WBT/CP-WAT 提取物口服后 NAOs 的药代动力学。采用 UPLC-QTOF-MS/MS 鉴定了 6 个准分子离子和特征碎片离子 m/z 192.1，并将其转移到 UPLC-TQ-MS/MS 中，作为 6 种 NAOs 的母-子离子对进行分析。在药代动力学方面，当给予单一化合物时，NAD-A 表现出双峰吸收特征，但当给予具有相似剂量的 CP 提取物时，其相对生物利用度更高。与 CP-WAT 相比，CP-WBT 中的 NAOs 达到最大血浆浓度的时间更短。
