Therapeutic effects of total saikosaponins from Radix bupleuri against Alzheimer's disease.

Alzheimer's disease (AD) is a neurodegenerative disease characterized by memory loss and cognitive dysfunction in the elderly, with amyloid-beta (Aß) deposition and hyperphosphorylation of tau protein as the main pathological feature. Nuclear factor 2 (Nrf2) is a transcription factor that primarily exists in the cytosol of hippocampal neurons, and it is considered as an important regulator of autophagy, oxidative stress, and inflammation. Total saikosaponins (TS) is the main bioactive component of Radix bupleuri (Chaihu). In this study, it was found that TS could ameliorate cognitive dysfunction in APP/PS1 transgenic mice and reduce Aß generation and senile plaque deposition via activating Nrf2 and downregulating the expression of ß-secretase 1 (BACE1). In addition, TS can enhance autophagy by promoting the expression of Beclin-1 and LC3-II, increasing the degradation of p62 and NDP52 and the clearance of phosphorylated tau (p-tau), and reducing the expression of p-tau. It can also downregulate the expression of nuclear factor-κB (NF-κB) to inhibit the activation of glial cells and reduce the release of inflammatory factors. In vitro experiments using PC12 cells induced by Aß, TS could significantly inhibit the aggregation of Aß and reduce cytotoxicity. It was found that Nrf2 knock-out weakened the inhibitory effect of TS on BACE1 and NF-κB transcription in PC12 cells. Moreover, the inhibitory effect of TS on BACE1 transcription was achieved by promoting the binding of Nrf2 and the promoter of BACE1 ARE1. Results showed that TS downregulated the expression of BACE1 and NF-κB through Nrf2, thereby reducing the generation of Aß and inhibiting neuroinflammation. Furthermore, TS can ameliorate synaptic loss and alleviate oxidative stress. In gut microbiota analysis, dysbiosis was demonstrated in APP/PS1 transgenic mice, indicating a potential link between gut microbiota and AD. Furthermore, TS treatment reverses the gut microbiota disorder in APP/PS1 mice, suggesting a therapeutic strategy by remodeling the gut microbe. Collectively, these data shows that TS may serve as a potential approach for AD treatment. Further investigation is needed to clarify the detailed mechanisms underlying TS regulating gut microbiota and oxidative stress.

The Alleviation of LPS-Induced Murine Acute Lung Injury by GSH-Mediated PEGylated Artesunate Prodrugs.

Acute lung injury (ALI) or its aggravated stage acute respiratory distress syndrome (ARDS) is a common severe clinical syndrome in intensive care unit, may lead to a life-threatening form of respiratory failure, resulting in high mortality up to 30-40% in most studies. Nanotechnology-mediated anti-inflammatory therapy is an emerging novel strategy for the treatment of ALI, has been demonstrated with unique advantages in solving the dilemma of ALI drug therapy. Artesunate (ART), a derivative of artemisinin, has been reported to have anti-inflammatory effects. Therefore, in the present study, we designed and synthesized PEGylated ART prodrugs and assessed whether ART prodrugs could attenuate lipopolysaccharide (LPS) induced ALI in vitro and in vivo. All treatment groups were conditioned with ART prodrugs 1 h before challenge with LPS. Significant increased inflammatory cytokines production and decreased GSH levels were observed in the LPS stimulated mouse macrophage cell line RAW264.7. Lung histopathological changes, lung W/D ratio, MPO activity and total neutrophil counts were increased in the LPS-induced murine model of ALI via nasal administration. However, these results can be reversed to some extent by treatment of ART prodrugs. The effectiveness of mPEG2k-SS-ART in inhibition of ALI induced by LPS was confirmed. In conclusion, our results demonstrated that the ART prodrugs could attenuate LPS-induced ALI effectively, and mPEG2k-SS-ART may serve as a novel strategy for treatment of inflammation induced lung injury.

[Study on potential effective components and mechanism of Zhishe Tongluo Capsules in treatment of ischemic stroke].

To explore the potential effective components and mechanism of Zhishe Tongluo Capsules in the treatment of ischemic stroke via network pharmacology, molecular docking and cellular experiment. The chemical constituents of Zhishe Tongluo Capsules were found by TCMSP, BATMAN-TCM and literatures. The constituents-target network was predicted by BATMAN-TCM database. Key words such as cerebral stroke, ischemic stroke and cerebral ischemic stroke were used to search ischemic stroke related targets, and then Venny Map was constructed based on the targets of traditional Chinese medicine and the targets of ischemic stroke. The overlapping targets were imported into STRING database to establish the interaction network. Furthermore, the core targets were screened out by Cytoscape software. Go and KEGG enrichment analysis were performed through DVIAD database. The results showed a total of 193 potential chemical constituents, 985 drug targets and 6 035 disease targets. There were 631 potential targets, 44 core targets and 55 potential active components for treating ischemic stroke through Venny mapping. GO enrichment analysis mainly involved response to hypoxia and positive regulation of ERK1/ERK2. KEGG pathway enrichment analysis mainly involved cholinergic synapse, cAMP signaling pathway, and calcium signaling pathway. Molecular docking data revealed that TP53, EGFR, IL6, INS, TNF and SRC had a good capability to bind with their corresponding active components. To ensure the protective effect Zhishe Tongluo Capsules on the inflammation reaction, an in vitro model of lipopolysaccharide(LPS)-induced RAW264.7 cells was built. The contents of IL-1α, IL-1ß, IL-6 and TNF-α in the supernatant were significantly decreased by enzyme linked immunosorbent assay(ELISA). The findings suggested that Zhishe Tongluo Capsules could prevent the injury of ischemic stroke by inhibiting the inflammation.

[A novel flavanone from Thymus przewalskii].

This study was to investigate the chemical constituents from the aerial parts of Thymus przewalskii. The chemical consti-tuents were separated and purified by column chromatography on silica gel, ODS, Sephadex LH-20 and semi-prepared HPLC, and their structures were determined by physicochemical properties and spectroscopic data. Four flavanones were isolated from the ethanol extract of the aerial parts of T. przewalskii, and identified as(2S)-5,6-dihydroxy-7,8,4'-trimethoxyflavanone(1), 5,4'-dihydroxy-6,7-dimethoxyflavanone(2),(2S)-5,4'-dihydroxy-7,8-dimethoxyflavanone(3), sakuranetin(4), respectively. Compound 1 was a new compound and its configuration was determined by CD spectrum, compound 3 was natural product which was isolated for the first time and their configurations were determined by CD spectra. Compound 2 was isolated from the genus Thymus for the first time and compound 4 was isolated from T. przewalskii for the first time. Furthermore, cytotoxicity test was assayed for the four flavanones. They exhibited weak cytotoxicity against human lung cancer cells(A549), with the IC_(50) from 74.5 to 135.6 µmol·L~(-1).