Preparation and characterisation of baicalin magnesium and its protective effect in ulcerative colitis via gut microbiota-bile acid axis modulation.

BACKGROUND: Scutellaria baicalensis Georgi is a well-known herb in traditional Chinese medicine that is frequently prescribed for various gastrointestinal conditions, including ulcerative colitis (UC). Its primary active constituent, baicalin, has poorly water solubility that reduces its efficacy. PURPOSE: To enhance the aqueous solubility of baicalin by optimising its extraction process. We compared the modulatory effects of isolated water-soluble baicalin and water-insoluble baicalin on UC, and delved deeper into the potential mechanisms of water-soluble baicalin. METHODS: We successfully extracted a more hydrophilic baicalin directly from an aqueous S. baicalensis Georgi extract through the process of recrystallisation following alcoholic precipitation of the aqueous extract obtained from S. baicalensis Georgi, eliminating the need for acid additives. This specific form of baicalin was conclusively identified by UV, IR, atomic absorption spectroscopy, elemental analysis, 1H NMR, 13C NMR, and ESI-HRMS. We subsequently compared the regulatory effects of baicalin on UC before and after optimisation, employing 16S rDNA sequencing, bile acid-targeted metabolomics, and transcriptome analysis to elucidate the potential mechanism of water-soluble baicalin; and the key genes and proteins implicated in this mechanism were verified through RT-PCR and western blotting. RESULTS: A new form of baicalin present in the aqueous solution of S. baicalensis Georgi was isolated, and its structural characterisation showed that it was bound to magnesium ions (baicalin magnesium) and exhibited favorable water solubility. Baicalin magnesium offers enhanced therapeutic benefits over baicalin for UC treatment, which alleviated the inflammatory response and oxidative stress levels while improving intestinal mucosal damage. Further investigation of the mechanism revealed that baicalin magnesium could effectively regulate bile acid metabolism and maintain intestinal microecological balance in UC mice, and suppress the activation of the nuclear factor-kappa B and peroxisome proliferator-activated receptor α signalling pathways, thereby playing a therapeutic role. CONCLUSIONS: Baicalin magnesium has good water solubility, which solves the bottleneck problem of water insolubility in the practical applications of baicalin. Moreover, baicalin magnesium exhibits therapeutic potential for UC significantly better than baicalin.

Protective effecs of baicalin magnesium on non-alcoholic steatohepatitis rats are based on inhibiting NLRP3/Caspase-1/IL-1ß signaling pathway.

Baicalin magnesium is a water-soluble compound isolated from the aqueous solution by Scutellaria baicalensis Georgi. Preliminary experiments have demonstrated that baicalin magnesium can exert protective effects against acute liver injury in rats induced by carbon tetrachloride or lipopolysaccharide combined with d-galactose by regulating lipid peroxidation and oxidative stress. The aim of this study was to investigate the protective effect of baicalin magnesium on non-alcoholic steatohepatitis (NASH) in rats and to elucidate the underlying mechanisms. NASH was induced through a high-fat diet (HFD) for 8 weeks, and Sprague-Dawley rats were intravenously injected with baicalin magnesium, baicalin, and magnesium sulfate for 2 weeks, respectively. Serum was obtained for biochemical analyses and the determination of oxidative stress indicators. Liver tissues were collected for use in liver index assessment, histopathological examination, inflammatory factor analysis, and protein and gene expression analysis. The results revealed that baicalin magnesium markedly improved HFD-induced lipid deposition, inflammatory response, oxidative stress, and histopathological impairments. And baicalin magnesium may exert a protective effect on NASH rats by inhibiting the NLR family pyrin domain involving the 3 (NLRP3)/caspase-1/interleukin (IL)-1ß inflammatory pathway. Additionally, the effect of baicalin magnesium was remarkably superior to that of equimolar baicalin and magnesium sulfate in regard to ameliorating NASH symptoms. In conclusion, the findings suggested that baicalin magnesium may represent a potential drug for the treatment of NASH.