Towards a better understanding of the therapeutic potential of Rhizoma Alismatis: A phytochemical and pharmacological review

Rhizoma Alismatis(RA),the dried rhizome of Alisma orientalis(Sam.)Juzep,isa widely used traditional herbal medicine popularly known as″Ze Xie″in Chinese.RA is an important crude herb component of several famous Chinese preparations including Zexie decoction,Liu Wei Di Huang pills,Wu Ling power and so on.It has been used to treat various ailments such as dysuria,edema,nephropathy,hypertension,hyperlipidemia and diabetes,etc.A wide range of chemical compounds mainly triterpenes,diterpenes and sesquiterpenes have been isolated from RA,among which the protostane-type triterpenes termed alisols attract the most attention owing to their unique chemical structure and various biological activity.The extract and active compounds of RAhave been demonstrated to possess a wide spectrum of pharmacological effects which support its clinical use,e.g.diuretic,hypoglycemic,hypolipidemic,hepatoprotective,preventing bone loss,anti-inflammatory andantivirus activities.In our previous studies,we have investigatedthe anti-proliferative activities of terpenoids isolated from RA and their structure-activity relationships.Alisol B 23-acetate was demonstrated to induce G1 phase cell cycle arrest and apoptosis,and inhibit migration and invasion of ovarian cancer cells.The present paper reviews the up-to-date information concerning the ethnopharmacology,phytochemistry,pharmacology and toxicology of RA.This information will be helpful for a better understanding of therapeutic potential of RA as wel as the further explorations.

Comprehensive metabolic profiling of Alismatis Rhizoma triterpenes in rats based on characteristic ions and a triterpene database

Alismatis Rhizoma(AR)is widely used in Chinese medicine,and its major bioactive components,triterpenes,reportedly possess various pharmacological activities.Therefore,it is very important to study the metabolism of triterpenes in vivo.However,the metabolism of AR triterpene extract has not been comprehensively elucidated due to its complex chemical components and metabolic pathways.In this study,an ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry method,which was based on the characteristic ions from an established database of known triterpenes,was used to analyze the major metabolites in rats following the oral administration of Alismatis Rhizoma extracts(ARE).As a result,a total of 233 constituents,with 85 prototype compounds and 148 metabolites,were identified for the first time.Hydrogenation,oxidation,sulfate and glucuronidation conjugation were the major metabolic pathways for triterpenes in AR.In addition,the mutual in vivo transformation of known ARE triterpenes was discovered and confirmed for the first time.Those results provide comprehensive insights into the metabolism of AR in vivo,which will be useful for future studies on its pharmacodynamics and pharmacokinetics.Moreover,this established strategy may be useful in metabolic studies of similar compounds.

Correlation analysis between the chemical contents and bioactivity for the quality control of Alismatis Rhizoma

In order to clarify regions of production and to discriminate processing methods, quantitative and qualitative analyses for saccharides and terpenes in 35 batches of Alismatis Rhizoma were performed.Methodologies included HPLC–PDA, HPLC–VWD and UHPLC–MSn, combined with principal component analysis(PCA) and partial least squares regression techniques(PLSR). The inhibitory effects of triterpenes and Alismatis Rhizoma extracts on lipase activity were evaluated in vitro. PLSR analysis revealed significant positive correlations(R2= 0.5795) between the contents of triterpenes 10, 14, 15, 18 and 22 and the inhibitory effects of Alismatis Rhizoma. The present study establishes an effective method for simultaneous determination of multiple components, and identifies key bioactive triterpenes. These results can be used for systematic and novel analytical strategies for the quality control of Alismatis Rhizoma production.

Hypolipidemic effects of Alismatis Rhizoma decoction on the lipid profile in hyperlipidemia rats by RNA-sequencing

As a disorder of lipid metabolism,hyperlipidemia(HLP)is characterized by elevated levels of lipids in the blood circulation.It is consistently related to the development of cardiovascular events and diseases associated with metabolic syndrome.Alismatis Rhizoma decoction(ARD),a well-known traditional Chinese medicine prescription,has long been used for treating vertigo,which is a symptom experienced by HLP patients.In this study,we aimed to investigate the hyperlipidemic activity and the potential molecular mechanisms of ARD in HLP rats at the transcriptional level.RNA sequencing and transcriptome analysis were performed collaboratively,including analysis of differentially expressed genes(DEGs),GO functions,and KEGG pathway analysis.The results showed that 1981 DEGs(1370 upregulated and 611 downregulated)were identified in the HFD group compared with the CON group.Moreover,474 DEGs(350 upregulated and 124 downregulated)were detected in the ARD group compared with the HFD group.Furthermore,GO analysis revealed that DEGs were mainly involved in the following functions:developmental process,response to an external stimulus,ion transport,alcohol binding,and plasma membrane part.Pathway analysis suggested that these DEGs were significantly enriched in bile secretion,malaria,cell adhesion molecules,retinol metabolism,the sphingolipid signaling pathway,chemical carcinogenesis,and the T cell receptor signaling pathway.In conclusion,our study demonstrated that ARD alleviated the lipid metabolism disorder caused by HLP through multiple mechanisms,which provided vital scientific evidence for further pharmacological studies of ARD.