Common Principles Of Scientific Connotation Change In Four Different Kinds Of Polygoni Multiflori Radix Praeparata

Polygoni Multiflori Radix Praeparata(PMRP),the processing products of the dry root of Polygonum Multiflorum Thunb.,has the effects of tonifying liver and kidney,enriching blood,growing and blackening hair,strenthening muscles and bones,and lowering turbidity and lipid.It is a holy medicine with unique tonifying effects and good clinic application.Throughout the ages,there have been a variety of processing methods of PMRP,such as steaming,braising,boiling,etc.,with the auxiliary materials including black bean sauce,rice wine,rice swill water,medicine juice,as well as a variety of auxiliary materials.Among them,some methods are still in use so far,like methods of braising with black bean sauce,steaming with water and steaming with black bean sauce included in the 2020 edition of The People’s Republic of China Pharmacopoeia.In addition,the processing method of steaming with black bean sauce and rice wine is recorded in the local processing specifications(Beijing,etc,).These PMRP processed by different processing methods are all used as "PMRP decoction pieces" with the same name,which are used in traditional Chinese medicine(TCM)preparation,prescription compatibility and so on.However,due to the lack of scientific and unified processing parameters,the quality of PMRP decoction pieces with the same name was uneven,which seriously impacted its clinical efficacy and safety.The quality of TCMs is closely related to the change of their scientific connotations(material basis,bioactivities,etc.)during the processing procedures.Based on this,clarifying the common principles of scientific connotation change in different kinds of PMRP is helpful to explain the scientific use of PMRP decoction pieces with the same name.What’s more,it is a good way to provide reference for the simplification of processing technology and quality control of decoction pieces.Therefore,based on the material basis change laws and kidney-tonifying efficacy study,this paper initially elucidated the common principles of scientific connotation change in four different kinds of PMRP.Sixteen kinds of PMRP decoction pieces were studied,which were processed by four different processing methods,including braising with black bean sauce,steaming with water,steaming with black bean sauce,steaming with black bean sauce and rice wine,for 24 h,32 h,40 h and 48 h,respectively.HPLC-QTOF-MS method was used for qualitative characterization of the compounds in the above PMRP decoction pieces.The relative peak areas of each compound were calculated and put into Principal Component Analysis(PCA)and Orthogonal Partial Least Squares Discrimination Analysis(OPLS-DA).Then,the significantly different compounds of PMRP processed for different processing times were screened by VIP value and P value.Correlation study between the above compounds and processing time was done and shown by heatmaps.As the results,a total of 93 compounds were identified by standard compounds comparison and characteristic fragment ions speculation,including 25 stilbenes,17 quinones,20 flavonoids,13 tannins,12 organic acids and 6 other classes.PCA and OPLS-DA analysis showed that PMRP processed for different processing times were significantly different,which indicated that the processing time had a greater influence on the material basis of PMRP.In addition,different PMRP processed for the same time had similar material basis.According to the VIP value>1.0 and P value<0.05,totally 46 compounds were screened,which contained 14 stilbenes including 2,3,5,4’-tetrahydroxystilbene-2-O-β-D-glucoside,9 quinones including emodin-8-O-βD-glucoside,9 flavonoids,6 tannins,2 organic acids and 6 other compounds.It could be seen in the heatmaps that with the extension of processing time,the contents of tetrahydroxystilbene glycosides,represented by 2,3,5,4’-tetrahydroxystilbene-2-O-βD-glucoside,gradually decreased,and the content of the corresponding aglycones increased.The change laws of most anthraquinone glycosides and flavonoid glycosides were similar to the tetrahydroxystilbene glycosides.However,the contents of some of the flavonoid aglycones,like dihydroflavones,isoflavones and chalcones,etc.,increased firstly and then decreased for the reason that they were thermally istable and their stuctures changed during processing.In general,with the increase of processing time,the content change laws of various compounds with different structures were different,while the content change laws of different kinds of PMRP were basically similar and with common characteristics.Based on the results of qualitative characterization,9 good efficacy-connected components selected from the 46 significantly different compounds in PMRP were quantitatively characterized.The contents of 2,3,5,4’-tetrahydroxystilbene-2-O-β-Dglucoside,emodin,physcion,emodin-8-O-β-D-glucoside and physcion-8-O-β-Dglucoside were determined by HPLC-DAD method.The content of polysaccharides was determined by UV-vis spectrophotometry and the contents of D-fructose,Danhydrous glucose and sucrose were determined by HPLC-ELSD method.The content change of 9 components during processing procedures were compared with line charts.It was shown that as the processing time prolonging,the contents of tetrahydroxystilbene glycoside and anthraquinone glycosides in different PMRP decoction pieces decreased gradually,and the contents of anthraquinone aglycones did not change significantly,which was the same as the qualification characterization.Additionally,the content of polysaccharide gradually increased,while the contents of monosaccharides and disaccharides gradually decreased,and the total content of saccharides showed an upward trend.Based on the results of quantitative determination,the cluster analysis and entropy weight TOPSIS(Technique for order preference by similarity to ideal solution)model were combined for the further analysis of the common change laws of substance basis in different PMRP decoction pieces,finding the common processing time range of PMRP.The results showed that,four different kinds of PMRP decoction pieces processed for 24 h and 32 h could be clustered into one group.However,only the entropy weight TOPSIS model scores of different PMRP processed for 32 h were high,showing that during the processing range of about 32 h,the components in the four kinds of PMRP were relatively stable with similar contents,and the decoction pieces had good processing effects and high quality.In conclusion,from the aspect of material basis,24-32 h was primarily considerd as the common processing time range of PMRP decoction pieces processed by four different processing methods.Based on the common change law analysis of material basis,12 PMRP were used as experimental objects,including the PMRP in the above common processing range(around 32 h)treated as the endpoint of processing,with the inferior processing time(24 h)and with the past processing time(40 h).Hydrocortisone-induced kidneydeficiency symdrone mouse model was taken as an example to search the common laws of treating kidney-deficiency of four different PMRP,for the further verification of the reasonability and scientificity of PMRP common processing range.As the results,after oral administration of different kinds of PMRP,in addition to the spleen and thymus index,the rest indexes of model mice were improved.It was found that PMRP treated kidney deficiency symdrone model mice mainly through the hypothalamic-pituitaryadrenal/gonadal axis,suggesting that its treatment of kidney deficiency was mainly related to the improvement of the body adrenal function and sexual function.Anthraquinone glycosides were speculated to be the material basis of kidney-tonifying effect of PMRP.The results showed that,when processed for 24-32 h,the efficacy of four kinds of PMRP was good and had "unification",meanwhile with relatively stable components,similar contents and good processing effect.Therefore,based on the study on the hydrocortisone-induced kidney deficiency symdrone mouse model,it was verified that 24-32 h was the common and the best processing time range of four different kinds of PMRP decoction pieces.To sum up,the four different processing methods of PMRP can all reduce the side effects by lowering the contents of tetrahydroxystilbene glucosides and anthraquinone glucosides,and enhance the kidney-tonifying effects by increasing the contents of saccharides.The change lines of the material basis in four kinds of PMRP during processing procedures were basically similar.In the processing time range of 24-32 h,the contents of the majorly bioactive components in different kinds of PMRP were similar,indicating that this processing time range was a stable range of PMRP material basis.In this stable range,the kidney-tonifying effect of different PMRP were the best and nearly the same based on the study on hydrocortisone-induced kidney-deficiency symdrone mouse.This result suggested that during a particular processing time range,the scientific connotations in four different kinds of PMRP were stable and similar,indicating that different processing kinds of PMRP had the possibility of "unification"and could be used as PMRP decoction pieces with the same name.This study provided references for simplifying the processing technology,standardizing the production parameters and stabilizing the quality of PMRP decoction pieces,and was of great significance for ensuring their clinical safety and efficacy.