Exploring therapeutic mechanisms of San-Huang-Tang in nonalcoholic fatty liver disease through network pharmacology and experimental validation.

ETHNOPHARMACOLOGICAL RELEVANCE: San-Huang-Tang (SHT), a traditional Chinese medicine (TCM) formula, has been clinically used to treat obesity and type 2 diabetes mellitus. Recently it has proved that SHT have a good effect on non-alcoholic fatty liver disease (NAFLD). AIM OF THE STUDY: Our study was designed to investigate the therapeutic mechanisms of the SHT against NAFLD. The data of SHT were obtained through network pharmacology platform and validated experimentally in vivo and in vitro. MATERIALS AND METHODS: The candidate targets of SHT were predicted by network pharmacological analysis and crucial targets were chosen by the protein-protein interaction (PPI) network. Furthermore, Gene Ontology (GO) and Kyoto encyclopedia of genes and Genomes (KEGG) were applied to analyze the NAFLD-related signaling pathways affected by SHT, and then the analysis results were verified with molecular biological experiments in vivo and in vitro. RESULTS: Molecules were screened with network pharmacological analysis, and then the improvement of insulin resistance of NAFLD mice was measured by IPITTs and IPGTTs. Through series of molecular experiments, it is revealed that SHT could increase the transcription of insulin receptor (INSR) and insulin receptor substrate (IRS1), and enhance the phosphorylation of both threonine protein kinase (AKT) and forkhead box O1 (FoxO1). CONCLUSIONS: Screened by bioinformatics and verified by experiments in vivo and in vitro, SHT could contribute to NAFLD by affecting insulin resistance via activating INSR/IRS1/AKT/FoxO1 pathway. Our research findings provide not only an experimental basis for the therapeutic effect of SHT but also a new target against NAFLD.

Xiao-Yao-San Formula Improves Cognitive Ability by Protecting the Hippocampal Neurons in Ovariectomized Rats.

Xiao-Yao-San (XYS) decoction is a traditional Chinese medicine formula. This study aimed to investigate the effect of XYS on cognitive abilities and its underlying mechanism in ovariectomized rats. Female Sprague-Dawley rats were ovariectomized and treated with XYS (3 g/kg or 9 g/kg) by gavage, with subcutaneous injection of 17-ß estradiol (E2, 2 µg/kg) as a positive drug control and gavage of 1 ml saline (0.9%) as a placebo control. After 6 weeks of treatment, rats were examined using the Morris water maze test. The estradiol level in the serum and hippocampus was measured by ELISA. Golgi staining was performed to observe neuronal morphology in the hippocampus. Apoptosis of hippocampal cells was observed by TUNEL staining. The protein content of N-methyl-D-aspartate receptor (NMDAR) 2A and 2B in the hippocampal CA1 region was determined by Western blot and immunohistochemistry. Expression of estrogen receptor (ER) and PI3K signaling was detected by Western blot. Compared with the sham group, both learning and memory were impaired in ovariectomized rats. Rats treated with E2 or high-dose XYS showed better learning and memory compared with the saline-treated rats. High-dose XYS significantly reduced escape latency in the spatial acquisition trial; meanwhile, the cross times and duration in the probe quadrant were increased in the spatial probe trial. High-dose XYS promoted the de novo synthesis of E2 content in the hippocampus but had no significant effect on the serum E2 level. Golgi staining indicated that high-dose XYS could increase the branch number and density of dendritic spines in the hippocampal CA1 area. TUNEL staining showed that high-dose XYS alleviated ovariectomy-induced neuronal apoptosis. The expression level of NMDAR2A and NMDAR2B in hippocampal CA1 was upregulated by XYS treatment. The beneficial effect of XYS was through activating ERα-PI3K signaling. In conclusion, high-dose XYS treatment can improve the cognitive abilities of ovariectomized rats by protecting the hippocampal neurons and restoring the hippocampal E2 level.

Baicalin attenuates hepatic injury in non-alcoholic steatohepatitis cell model by suppressing inflammasome-dependent GSDMD-mediated cell pyroptosis.

Baicalin (BA), a flavone glycoside, is the constituent of Scutellaria baicalensis, a Chinese herbal medicine used to treat non-alcoholic steatohepatitis (NASH). However, the mechanism of BA on NASH is still not clear. Here, the improving effect of BA on hepatocyte through inhibition of pyroprosis was investigated in vitro. With a cell model of NASH exposing HepG2 cells in free fatty acids (FFA), we revealed that BA could improve hepatocyte from FFA-induced morphological damage and death. And then through transcriptomes screening, a significant down-regulation of NLR pyrin domain containing 3 (Nlrp3), gasdermin D (Gsdmd), andinterleukin-1 beta (IL-1ß) expression were found after BA treatment. Further analysis confirmed that BA could decrease the levels of NLRP3 and GSDMD, as well as the release of IL-1ß and IL-18, resulting in the reduction of pyroptosis. Moreover, the improving effect of BA could be attenuated by Gsdmd knockdown. In conclusion, BA can reduce pyroptosis of hepatocyte by blocking NLRP3-GSDMD signaling in vitro.

Saikosaponin­D improves fear memory deficits in ovariectomized rats via the action of estrogen receptor­α in the hippocampus.

Saikosaponin­D (SSD), which is the main bioactive component in the traditional Chinese medicine Chai Hu (Bupleurum falcatum L), possesses estrogen­like properties and is widely used in treating estrogen­related neurological disorders. The current study aimed to investigate the protective effects of SSD on the fear memory deficit in ovariectomized (OVX) rats and the potential underlying mechanism. SSD treatment significantly prolonged freezing time in OVX rats in a manner similar to that of estradiol (E2), whereas this effect was markedly suppressed by co­administration of ICI182780, a non­selective estrogen receptor (ER) inhibitor. The expression of ERα in the hippocampus of OVX rats was significantly elevated by SSD; however, Erß expression and E2 synthesis were not markedly affected by SSD treatment. Collectively, this study demonstrated that SSD­mediated fear memory improvement in OVX rats may be attributed not to E2 levels or ERß activity, but to ERα activation in the hippocampus.