Panax quinquefolius (PQ) and Acorus gramineus (AG) are drug target pairs in traditional Chinese medicine (TCM), which are used to treat age-related diseases. In the present study, we simultaneously determined the contents of four main bioactive ginsenosides (Rb₁, Rb₂, Rd, and Re) in rat plasma using an ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. Plasma specimens were purified by using the solid-phase extraction procedure, and separation was performed on Waters ACQUITY UPLC BEH C₁₈ (100 mm × 2.1 mm, 1.7 μm) in multiple reaction monitoring (MRM) mode and negative electrospray ionization (ESI) mode. The established UPLC-MS/MS method showed good linear correlation (r ≥ 0.9978), stability (−11.93 to 12.11%), precision (RSD < 14.63%), and recovery (76.43%–95.20%). The lower limit of quantification was 3.6 ng/mL for Rb₁, 1.6 ng/mL for Rb₂, 1.2 ng/mL for Rd, and 2.5 ng/mL for Re. This validated method was successfully employed to investigate the pharmacokinetics of the four ginsenosides in rat plasma after oral administration of PQ-AG and PQ extracts. The results revealed the pharmacokinetic profiles of PQ-AG drug pair and clarified that AG played a critical role in stimulating the absorption of active ginsenosides in PQ. Collectively, our findings provided valid and reliable evidence for the rational use of PQ-AG in clinical practice.

The objective of this study was to examine the safety of multiple repeated percutaneous punctures of cisterna magna for collecting cerebrospinal fluid (CSF) and preliminarily determine the optimal time interval and volume at each collection. Sixty Wistar rats were randomly assigned to six groups: 10 d-0 μL, 10 d-100 μL (100 μL CSF collected at an interval of 10 days), 10 d-150 μL, 15 d-0 μL, 15 d-100 μL, and 15 d-150 μL. CSF was collected by percutaneous puncture of the cisterna magna at four time-points. Simultaneously, locomotor activity, cisterna magna pressure, and acetylcholine levels in the CSF were monitored. Compared with the 10 d-0 μL group, the escape latency by Morris water maze was significantly prolonged in the 10 d-100 μL and 10 d-150 μL groups (P<0.05). Compared with the 15 d-0 μL group, the indices of 15 d-100 μL and 15 d-150 μL groups had no significant differences. When compared with that at the first training, the exception of the 10 d-150 μL and 15 d-150 μL groups, significant differences in escape latency were found at the 6th attempt (P<0.05). Compared with baseline readings for each group, the cisterna magna pressure in the 10 d-150 μL group began to decrease significantly from the third measurement (P<0.05). The optimal time interval during four CSF collections (100 μL per collection) via cisterna magna percutaneous puncture was determined to be 15 days. The procedure did not significantly affect learning processes, performance, or other related indices.

Background: Long-term diabetes mellitus may precipitate severe complications, including cognitive dysfunction. Existing research has shown that diabetic cognitive impairment (DCI) in rats is characterized by memory deterioration and a disordered arrangement of hippocampal cells. The Shichangpu–Xiyangshen herb pair (SX) effectively improved the pathological changes induced by DCI. However, the role of SX in regulating the physiological and behavioral responses to DCI remains unclear. Methods: We sought to determine the small-molecule metabolites of cerebrospinal fluid (CSF) and delineate the pathways to elucidate the potential mechanism of the effect of SX in the treatment of DCI by metabolomics strategies, focusing on key mechanisms. Behavioral assessments were conducted on DCI rats and the rats treated with SX, as well as an evaluation of neuronal morphology in the hippocampal region. Metabolomics was used to analyze biomarkers in cerebrospinal fluid at different time points during the development of DCI, to uncover the underlying core mechanisms of DCI, and to investigate the regulatory effects of SX on these core mechanisms. The mechanisms of SX on DCI were investigated using quantitative reverse transcription polymerase chain reaction, immunohistochemistry, Western blot, and ELISA. Results: The Morris water maze (MWM) and social interaction test results revealed that SX administration effectively counteracted cognitive impairments in rats with DCI while simultaneously diminishing pathological damage in the CA1, CA3, and DG hippocampal regions. Further analysis showed that SX restored the significantly reduced levels of IL-8, ROX, and TNF-α, and reduced Aβ plaque formation (as indicated by APP and BACE1 protein expression). Simultaneously, SX markedly ameliorated arachidonic acid metabolic disorders in DCI, including significant reductions in arachidonic acid (AA), PGE2, and LTB4 and reduced expression of COX-2 (PTGS2) and 5-LOX (ALOX-5). Conclusions: Our findings indicate that SX effectively counteracted cognitive impairment in rats with DCI by inhibiting AA metabolism through both cyclooxygenase and lipoxygenase pathways, thereby minimizing neuronal damage.