No abstract

Rehmannia glutinosa Libosch (RG), is officially listed in the Chinese Pharmacopoeia and is widely used in China. The leaves of RG (LR) is an important vegetative organ of the plant. At present, the total glycosides of RG (TLR) were extracted from RG, and developed a national second class of new drugs to the Dihuangye total glycoside capsule (DTG). Additionally, DTG has the effect of nourishing yin and tonifying kidney, promoting blood circulation and blood cooling, and applicable to chronic glomerulonephritis mild to Qi and Yin Deficiency. Moreover, diabetic nephropathy (DN) rats model was induced by intraperitoneal injection of a small dose of streptozotocin (45 mg/kg) and high-fat diet and plus 5% glucose drinking water. Over 15 days, after oral administration TLR and DTG in DN rats, samples from serum, urine and kidney were collected for biochemical indicators measurements, pathological analysis, western blotting and metabolomics. Therefore, the analytical results of biochemical indicators, histopathological observations and western blotting showed that TLR and DTG exhibited a significant effect in renal protection. And 27 endogenous metabolites (12 in serum and 15 in urine) could be tentatively identified in the process of DN in rats using metabolomics method. Those endogenous metabolites were chiefly involved in sphingolipid metabolism; pentose, glucuronate interconversion; terpenoid backbone biosynthesis; purine metabolism and retinol metabolism. After drug intervention, these endogenous metabolites turned back to normal level some extent (P < 0.05). Furthermore, TLR and DTG prevent high glucose-induced glomerular mesangial cells (GMCs) by inhibiting TGF-β1 and Wnt/β-catenin signaling pathway, providing a powerful supports to develop a new therapeutic agent for DN. This study paved the way for further exploration of the pathogenesis of DN, early diagnosis and the evaluation of curative effect.

No abstract

† These authors contributed equally to this work.In the process of planting and harvesting of Rehmannia glutinosa, only the underground part is used, and a large number of stems and leaves that are considered non-medicinal parts are usually discarded. Recent studies have shown that the chemical components in the leaves are similar to those identified in the roots. In this study, we selected leaves and roots from Rehmannia glutinosa at different growth stages and leaves from different cultivation regions to investigate the dynamic accumulation of three kinds of glycosides (catalpol, acteoside, and ajugol), six kinds of carbohydrates (rhamnose, fructose, sucrose, melibiose, stachyose, and verbascose), and acidic and neutral polysaccharides via rapid quantitative analysis technology, including ultra high performance liquid chromatography triple quadrupole tandem mass spectrometry, high-performance liquid chromatography, and UV spectroscopy. The results showed that the Rehmannia glutinosa leaves also contained higher content of catalpol (3.81∼24.51 mg/g), ajugol (0.55∼10.23 mg/g), acteoside (1.34∼21.16 mg/g), monosaccharide/ oligosaccharides (7.71∼120.73 mg/g), and polysaccharides (5.63∼15.57%). In this study, we developed a new rapid and simple method for determination to clarify the distribution and dynamic accumulation of nine glycosides and saccharides in Rehmannia glutinosa leaves to provide a scientific basis for the discovery, development, and utilization of the resource value of Rehmannia glutinosa leaves.

Rehmannia glutinosa Libosch (RG), is officially listed in the Chinese Pharmacopoeia and is widely used in China. In this paper, a sensitive and rapid ultra-performance liquid chromatography-mass spectrometry method including multiple-reaction monitoring mode was developed and applied to study the pharmacokinetic effect of acteoside from total glycoside extracted from the leaves of Rehmannia (TLR) and Dihuangye total glycoside capsule (DTG) in normal and diabetic nephropathy rats. The diabetic nephropathy rat model was induced by intraperitoneal injection of a small dose of streptozotocin and high-fat diet and plus 5% glucose drinking water. Samples of plasma of rats were obtained at different times after rats were administered TLR (7.2 g/kg) and DTG (360 mg/kg). After deproteinization by acetonitrile, the concentrations of acteoside in rats at different time points were detected by UPLC-TQ-MS method and pharmacokinetics parameters were calculated using DAS 3.2.8 software. A good linearity of acteoside was shown in the range of 8.51-3404.8 ng/m L (r = 0.9987). The mean extraction recovery of analyte was in the range of 63.55-79.49%, and the intra- and inter-day RSD values were <8.8%. Compared with the normal group, the maximum plasma concentration, AUC , AUC and apparent plasma clearance corresponding dose in model group rats decreased significantly. After rats were administered TLR and DTG, the acteoside reached the maximum plasma concentration at about 15 min. The method proved to be simple, rapid and specific, and to be suitable for the determination of acteoside in plasma of diabetic nephropathy rats and pharmacokinetic study.