Institute of Food Safety and Analytical Sciences, Nestlé Research, Vers-chez-les Blanc, 1000, Lausanne 26, Switzerland.
Nestlé Research, Singapore Hub, 29 Quality Road, Singapore, 618802, Singapore.
Anal Bioanal Chem. 2020 Nov;412(28):7871-7880. doi: 10.1007/s00216-020-02919-8. Epub 2020 Sep 4.
Previous studies support that myo- and D-chiro-inositol isomers are promising bioactives for the treatment of women with polycystic ovary syndrome and for lowering the risk of gestational diabetes mellitus in pregnant women, whereas scyllo-inositol may have some benefits for neurological disorders (e.g., Alzheimer's disease). Though potentially useful to better understand inositol isomer metabolism and study their role in health and disease, routine analysis of inositol isomers in plasma and urine with a single analytical method is not yet feasible due to the lack of a suitable analytical assay. To address this, we developed and validated a robust ultra-high-performance-liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method for the quantification of inositol isomers in plasma and urine. This method resolves seven inositol isomers with accurate quantification of total chiro- (D and L enantiomers), myo-, and scyllo-inositols and is semi-quantitative for neo-inositol. For urine and plasma myo-inositol, the method repeatability and intermediate reproducibility were below 6% and 8%, respectively. Then, for both chiro- and scyllo-inositols, repeatability and intermediate reproducibility were below 10% and 14%, respectively. A pilot study was carried out to quantify and compare the pattern of inositol isomers in urine and plasma of non-pregnant and pregnant women and showed for the first time that urinary myo- and scyllo-inositol concentrations were significantly higher for women in the third trimester of pregnancy compared with non-pregnant women. These findings warrant further research to understand the biological significance of the observed differences in inositol profiles and suggest a potential role of scyllo-inositol.Graphical abstract Plasma and urinary inositol isomer profiles measured by UHPLC-MS/MS reveal differences in scyllo-inositol levels between non-pregnant and pregnant women.
先前的研究支持肌醇和 D-手性肌醇异构体是治疗多囊卵巢综合征妇女和降低孕妇患妊娠糖尿病风险的有前途的生物活性物质，而表肌醇可能对神经紊乱（如阿尔茨海默病）有一些益处。虽然分析肌醇异构体代谢并研究其在健康和疾病中的作用可能很有用，但由于缺乏合适的分析方法，目前还无法用单一分析方法常规分析血浆和尿液中的肌醇异构体。为了解决这个问题，我们开发并验证了一种用于定量分析血浆和尿液中肌醇异构体的强大超高效液相色谱串联质谱（UHPLC-MS/MS）方法。该方法可分离出 7 种肌醇异构体，可准确定量手性（D 和 L 对映体）、肌醇和表肌醇，对新肌醇进行半定量分析。对于尿和血浆中的肌醇，方法重复性和中间重现性分别低于 6%和 8%。对于手性和表肌醇，重复性和中间重现性分别低于 10%和 14%。进行了一项初步研究，以定量和比较非孕妇和孕妇尿液和血浆中肌醇异构体的模式，并首次表明，与非孕妇相比，孕妇第三个三个月的尿肌醇和表肌醇浓度显著升高。这些发现需要进一步研究，以了解观察到的肌醇谱差异的生物学意义，并表明表肌醇可能具有潜在作用。
