[Different processed products of Polygonati Rhizoma treat Alzheimer's disease in rats: urine metabolomics based on UPLC-Q/TOF-MS].

The study investigated the effects of different processed products of Polygonati Rhizoma(black bean-processed Polygonati Rhizoma, BBPR; stewed Polygonati Rhizoma, SPR) on the urinary metabolites in a rat model of Alzheimer's disease(AD). Sixty SPF-grade male SD rats were randomized into a control group, a model group, a donepezil group, a BBPR group, and a SPR group, with twelve rats in each group. Other groups except the control group were administrated with D-galactose injection(100 mg·kg~(-1)) once a day for seven weeks. The control group was administrated with an equal volume of normal saline once a day for seven consecutive weeks. After three weeks of D-galactose injection, bilateral hippocampal Aß_(25-35) injections were performed for modeling. The rats were administrated with corresponding drugs(10 mL·kg~(-1)) by gavage since week 2, and the rats in the model and control group with an equal volume of double distilled water once a day for 35 continuous days. The memory behaviour and pathological changes in the hippocampal tissue were observed. The untargeted metabolites in the urine were detected by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q/TOF-MS). Principal component analysis(PCA) and orthogonal partial least square-discriminant analysis(OPLS-DA) were employed to characterize and screen differential metabolites and potential biomarkers, for which the metabolic pathway enrichment analysis was conducted. The results indicated that BBPR and SPR increased the new object recognition index, shortened the escape latency, and increased the times of crossing the platform of AD rats in the Morris water maze test. The results of hematoxylin-eosin(HE) staining showed that the cells in the hippocampal tissue of the drug administration groups were closely arranged. Moreover, the drugs reduced the content of interleukin-6(IL-6, P<0.01) and tumor necrosis factor-α(TNF-α) in the hippocampal tissue, which were more obvious in the BBPR group(P<0.05). After screening, 15 potential biomarkers were identified, involving two metabolic pathways: dicoumarol pathway and piroxicam pathway. BBPR and SPR may alleviate AD by regulating the metabolism of dicoumarol and piroxicam.

[Mechanism analysis of repeatedly steamed and sundried Rehmanniae Radix Praeparata in delaying brain aging in ovariectomized mice based on proteomics].

The present study explored the effect and mechanism of repeatedly steamed and sundried Rehmanniae Radix Praeparata(RRP) in delaying brain aging in ovariectomized mice. After ovariectomy, the mice were randomly divided into a model group, an estradiol valerate group(0.3 mg·kg~(-1)), and low-(1.0 g·kg~(-1)), medium-(2.0 g·kg~(-1)), and high-dose(4.0 g·kg~(-1)) RRP groups, and a sham operation group was also set up, with 15 mice in each group. One week after the operation, intragastric administration was carried out for 15 consecutive weeks. The step-down test and Morris water maze test were used to detect the behavioral changes of mice. HE staining and Nissl staining were used to observe the morphological changes of mouse brain tissues. Immunohistochemistry was used to detect the expression of Aß and ER_ß in mouse brain tissues. The serum estrogen levels and cholinesterase and cholinesterase transferase levels in brain tissues of mice were detected by assay kits. The extracted hippocampal protein was detected by the Nano-ESI-LC-MS system, identified by the Protein Discovery, and analyzed quantitatively and qualitatively by the SIEVE. The PANTHER Classification System was used for GO analysis and KEGG pathway enrichment analysis of the differential proteins. Compared with the sham operation group, the model group showed decreased learning and memory ability, shortened step-down latency(P<0.05), prolonged escape latency(P<0.05), reduced platform crossings and residence time in the target quadrant, scattered nerve cells in the hippocampus with enlarged intercellular space, increased expression of Aß-positive cells(P<0.05), declining expression of ER_ß-positive cells and estrogen level(P<0.05), and weakened cholinergic function(P<0.05). Compared with the model group, the RRP groups showed improved learning and memory ability, prolonged step-down latency(P<0.05), increased estrogen level(P<0.05), neatly arranged nerve cells in the hippocampus with complete morphology, declining Aß-positive cells, and elevated expression of ER_ß-positive cells. A total of 146 differential proteins were screened out by proteomics, and KEGG pathway enrichment yielded 75 signaling pathways. The number of proteins involved in the dopaminergic synapse signaling pathway was the largest, with 13 proteins involved. In summary, RRP can delay brain aging presumedly by increasing the level of estrogen, mediating the dopaminergic synapse signaling pathway, and improving cholinergic function.