To establish an LC-MS/MS method for the determination of the abundance data of dexamethasone-related metabolic enzymes and transporters in the placenta of Chinese pregnant women.
A Shim-pack GISS-HP C18 (100 mm×2.1 mm, 1.9 μm) chromatographic column was used, and the mobile phases were consisted of 0.2% formic acid-water (phase A) and 0.2% formic acid-acetonitrile (phase B) with gradient elution at a flow rate of 0.2 mL·min-1. The post-column phase C consisted of 0.5% ethylene glycol-acetonitrile was added at a flow rate of 0.1 mL·min-1, and the ESI source positive ion MRM mode was used for quantitative analysis. The established method was investigated methodologically and the expression levels of 11β hydroxysteroid dehydrogenase 1(11β-HSD1), 11β hydroxysteroid dehydrogenase 2(11β-HSD2), cytochrome P450 3A4 enzyme (CYP3A4) and P-glycoprotein protein (P-gp) were quantitatively analyzed in the placenta of Chinese pregnant women in the third trimester.
The established LC-MS/MS method had a linear range of 0.1-100 nmol·L-1(r >0.999). The precision and accuracy results met the requirements of the biological sample analysis method verification in Chinese Pharmacopoeia (RSD≤15%), and the stability results showed that the samples were stability. The protein abundance of 11β-HSD2, 11β-HSD1, CYP3A4 and P-gp were (84.46±59.97) pmol·g-1, (11.44±3.73) pmol·g-1, (8.83±2.78) pmol·g-1 and (7.94±4.10) pmol·g-1, respectively. Besides, the results of the study also showed that there was no significant difference in the distribution of related metabolic enzymes and transporters in different parts of the placenta. However, there was a significant difference in the abundance of P-gp in the placenta between Chinese people (7.94±4.10) pmol·g-1 and white people (4.41±2.46) pmol·g-1.
The LC-MS/MS method established in this study has high accuracy and sensitivity and is suitable for detecting the abundance values of dexamethasone-related metabolic enzymes and transporters in human placenta.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |