Inhibitory effects of cassiae semen extract on the formation of 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) in model system.

Introduction: 2-Amino-1-methyl-6-phenylimidazole [4,5-b] pyridine (PhIP), a heterocyclic amine (HAA), is found in meat products heated at high temperatures. However, PhIP is a mutagenic and potential carcinogenic compound. Cassiae semen, a type of medicine and food homology plant, is abundant in China and has been less applied for inhibiting heterocyclic amines. Methods: To investigate the inhibitory effect of cassiae semen extract on PhIP formation within a model system and elucidate the inhibitory mechanism, an ultrasonic-assisted method with 70% ethanol was used to obtain cassiae semen extract, which was added to a model system (0.6 mmol of phenylalanine: creatinine, 1:1). PhIP was analyzed by LC-MS to determine inhibitory effect. The byproducts of the system and the mechanism of PhIP inhibition were verified by adding the extract to a model mixture of phenylacetaldehyde, phenylacetaldehyde and creatinine. Results: The results indicated that PhIP production decreased as the concentration of cassiae semen extract increased, and the highest inhibition rate was 91.9%. Byproduct (E), with a mass-charge ratio of m/z 199.9, was detected in the phenylalanine and creatinine model system but was not detected in the other systems. The cassiae semen extract may have reacted with phenylalanine to produce byproduct (E), which prevented the degradation of phenylalanine by the Strecker reaction to produce phenylacetaldehyde. Discussion: Cassiae semen extract consumed phenylalanine, which is the precursor for PhIP, thus inhibiting the formation of phenylacetaldehyde and ultimately inhibiting PhIP formation. The main objective of this study was to elucidate the mechanism by which cassiae semen inhibit PhIP formation and establish a theoretical and scientific foundation for practical control measures.

Biotransformation of Bioactive Metabolites in Cassiae Semen by Endogenous Enzymes and Probiotics.

The present study evaluated the potential of endogenous enzymes and probiotics in transforming bioactive metabolites to reduce the purgative effect and improve the functional activity of Cassiae Semen and verified and revealed the biotransformation effect of endogenous enzymes. Although probiotics, especially Lactobacillus rhamnosus, exerted the transformation effect, the endogenous enzymes proved to be more effective in transforming the components of Cassiae Semen. After biotransformation by endogenous enzymes for 12 h, the levels of six anthraquinones in Cassiae Semen increased by at least 2.98-fold, and free anthraquinones, total phenolics, and antioxidant activity also showed significant improvement, accompanied by an 82.2% reduction in combined anthraquinones responsible for the purgative effect of Cassiae Semen. Further metabolomic analysis revealed that the biotransformation effect of endogenous enzymes on the bioactive metabolites of Cassiae Semen was complex and diverse, and the biotransformation of quinones and flavonoids was particularly prominent and occurred by three primary mechanisms, hydrolyzation, methylation, and dimerization, might under the action of glycosyl hydrolases, SAM-dependent methyltransferases, and CYP450s. Accordingly, biotransformation by endogenous enzymes emerges as a mild, economical, food safety risk-free, and effective strategy to modify Cassiae Semen into an excellent functional food.

Chemical composition and absorption characteristics of Raw and Prepared Cassiae Semen extracts based on ultra-high-performance liquid chromatography-quadrupole Orbitrap high-resolution mass spectrometry.

In traditional Chinese medicine, the two commodity forms of Cassiae Semen Raw and Prepared Cassiae Semen, exert different clinical applications, in which Prepared Cassiae Semen is commonly used to treat liver and eye diseases. However, the material basis of Raw and Prepared Cassiae Semen remains unclear due to the limited studies on their overall composition and metabolism in vivo. In this study, an integrated analysis strategy based on ultra-high-performance liquid chromatography coupled with quadrupole-Orbitrap high-resolution mass spectrometry was established to systematically screen the prototype and metabolite constituents of Raw and Prepared Cassiae Semen. Automatic matching analysis of metabolites was performed on Compound Discoverer software based on the function of predicting metabolites. Using this strategy, a total of 77 compounds in Raw Cassiae Semen and 71 compounds in Prepared Cassiae Semen were identified. Furthermore, in vivo study, 46 prototype components and 104 metabolites from the Raw Cassiae Semen group and 41 prototype components and 87 metabolites from the Prepared Cassiae Semen group were unambiguously or preliminarily identified in mice (plasma, urine, feces, eye, and liver). This is the first study of chemical component analysis and in vivo metabolite profiling of Raw and Prepared Cassiae Semen.

Cassiae Semen improves non-alcoholic fatty liver disease through autophagy-related pathway.

Objective: Cassiae Semen (CS, Juemingzi in Chinese) has been used for thousands of years in ancient Chinese history for relieving constipation, improving liver function as well as preventing myopia. Here we aimed to elucidate the anti-steatosis effect and underlying mechanism of CS against non-alcoholic fatty liver disease (NAFLD). Methods: High-performance liquid chromatography (HPLC) was used to identify the major components of CS water extract. Mice were fed with a high-fat and sugar-water (HFSW) diet to induce hepatic steatosis and then treated with CS. The anti-NAFLD effect was determined by measuring serum biomarkers and histopathology staining. Additionally, the effects of CS on cell viability and lipid metabolism in oleic acid and palmitic acid (OAPA)-treated HepG2 cells were measured. The expression of essential genes and proteins involved in lipid metabolism and autophagy signalings were measured to uncover the underlying mechanism. Results: Five compounds, including aurantio-obtusin, rubrofusarin gentiobioside, cassiaside C, emodin and rhein were simultaneously identified in CS extract. CS not only improved the diet-induced hepatic steatosis in vivo, as indicated by decreased number and size of lipid droplets, hepatic and serum triglycerides (TG) levels, but also markedly attenuated the OAPA-induced lipid accumulation in hepatocytes. These lipid-lowering effects induced by CS were largely dependent on the inhibition of fatty acid synthase (FASN) and the activation of autophagy-related signaling, including AMP-activated protein kinase (AMPK), light chain 3-II (LC3-II)/ LC3-1 and autophagy-related gene5 (ATG5). Conclusion: Our study suggested that CS effectively protected liver steatosis via decreasing FASN-related fatty acid synthesis and activating AMPK-mediated autophagy, which might become a promising therapeutic strategy for relieving NAFLD.

Cassiae Semen: A comprehensive review of botany, traditional use, phytochemistry, pharmacology, toxicity, and quality control.

ETHNOPHARMACOLOGICAL RELEVANCE: Cassiae Semen, belonging to the family Leguminosae, is derived from the dry mature seeds of Cassia obtusifolia L. or Cassia tora L. and has long been used as a laxative, hepatoprotective, improve eyesight, and antidiabetic complications medicine or functional food in Asia. AIMS OF THE REVIEW: This review summarizes the integrated research progress of botany, traditional uses, phytochemistry, pharmacology, toxicity, and quality control of Cassiae Semen. Additionally, the emerging challenges and possible developing directions are discussed as well. MATERIALS AND METHODS: The information on Cassiae Semen was collected from published scientific materials, including ancient books of traditional Chinese Medicine; Ph.D. and M. Sc. dissertations; monographs on medicinal plants; pharmacopoeia of various countries and electronic databases, such as PubMed, Web of Science, ACS, Science Direct, J-STAGE, Springer link, Taylor, CNKI and Google Scholar, etc. RESULTS: First, the traditional uses and plant origins of Cassiae Semen are outlined. Secondly, approximately 137 compounds, including anthraquinones, naphthopyranones, naphthalenes, flavones, polysaccharides and other compounds, have been isolated and identified from Cassia obtusifolia L. and Cassia tora L. Third, the pharmacological activities and mechanisms of crude extract of Cassiae Semen and its main bioactive compounds are summarized. Moreover, the processing, toxicity, and quality control are introduced briefly. CONCLUSIONS: Cassiae Semen is a frequently used Chinese Materia Medica with pharmacological effects that mainly affect the digestive system, cardiovascular systems and nervous system. This review summarized its botany, traditional uses, phytochemistry, and pharmacology, it also exhibited recent scientific research advances and gaps, which provide a deeper insight into the understanding and application of Cassiae Semen. In future research on Cassiae Semen, more attention should be given to the pharmacological activities of naphthopyranones and polysaccharides and the mechanism of action for improving eye diseases. Meanwhile, it is essential to focus on strengthening the study on the pharmacokinetics research and the safety evaluation of related health products research.

Exploring the mechanism of Cassiae semen in regulating lipid metabolism through network pharmacology and experimental validation.

BACKGROUND: Multiple studies have assessed the role of Cassiae semen (CS) in regulating lipid metabolism. However, the mechanism of action of CS on non-alcoholic fatty liver disease (NAFLD) has seen rare scrutiny. OBJECTIVE: The objective of this study was to explore the regulatory mechanism of CS on lipid metabolism in NAFLD. METHODS: Components of CS ethanol extract (CSEE) were analyzed and identified using UPLC-Q-Orbirap HRMS. The candidate compounds of CS and its relative targets were extracted from the Traditional Chinese Medicine Systems Pharmacology, Swiss-Target-Prediction, and TargetNet web server. The Therapeutic Target Database, Genecards, Online Mendelian Inheritance in Man, and DisGeNET were searched for NAFLD targets. Binding affinity between potential core components and key targets was established employing molecular docking simulations. After that, free fatty acid (FFA)-induced HepG2 cells were used to further validate part of the network pharmacology results. RESULTS: Six genes, including Caspase 3 (CASP3), phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit α (PIK3CA), epidermal growth factor receptor (EGFR), and amyloid ß (A4) precursor protein (APP) were identified as key targets. The mitogen-activated protein kinase (MAPK) signaling pathway was found to associate closely with CS's effect on NAFLD. Per molecular docking findings, toralactone and quinizarin formed the most stable combinations with hub genes. About 0.1 (vs. FFA, P<0.01) and 0.2 (vs. FFA, P<0.05) mg/ml CSEE decreased lipid accumulation in vitro by reversing the up-regulation of CASP3, EGFR, and APP and the down-regulation of PIK3CA. CONCLUSION: CSEE can significantly reduce intracellular lipid accumulation by modulating the MAPK signaling pathway to decrease CASP3 and EGFR expression.

Integrated metabolic and transcriptomic profiles reveal the germination-associated dynamic changes for the seeds of Cassia obtusifolia L.

INTRODUCTION: The seeds of Cassia obtusifolia L. (Cassiae [C.] semen) have been widely used as both food and traditional Chinese medicine in China. OBJECTIVES: We aimed to analyze the metabolic mechanisms underlying C. semen germination. MATERIALS AND METHODS: Different samples of C. semen at various germination stages were collected. These samples were subjected to 1 H-NMR and UHPLC/Q-Orbitrap-MS-based untargeted metabolomics analysis together with transcriptomics analysis. RESULTS: A total of 50 differential metabolites (mainly amino acids and sugars) and 20 key genes involved in multiple pathways were identified in two comparisons of different groups (36 h vs 12 h and 84 h vs 36 h). The metabolite-gene network for seed germination was depicted. In the germination of C. semen, fructose and mannose metabolism was activated in the testa rupture period, indicating more energy was needed (36 h). In the embryonic axis elongation period (84 h), the pentose and glucuronate interconversions pathway and the phenylpropanoid biosynthesis pathway were activated, which suggested some nutrient sources (nitrogen and sugar) were in demand. Furthermore, oxygen, energy, and nutrition should be supplied throughout the whole germination process. These global views open up an integrated perspective for understanding the complex biological regulatory mechanisms during the germination process of C. semen.

Cassiae Semen improves non-alcoholic fatty liver disease through autophagy-related pathway / 中草药·英文版

OBJECTIVE@#Cassiae Semen (CS, Juemingzi in Chinese) has been used for thousands of years in ancient Chinese history for relieving constipation, improving liver function as well as preventing myopia. Here we aimed to elucidate the anti-steatosis effect and underlying mechanism of CS against non-alcoholic fatty liver disease (NAFLD).@*METHODS@#High-performance liquid chromatography (HPLC) was used to identify the major components of CS water extract. Mice were fed with a high-fat and sugar-water (HFSW) diet to induce hepatic steatosis and then treated with CS. The anti-NAFLD effect was determined by measuring serum biomarkers and histopathology staining. Additionally, the effects of CS on cell viability and lipid metabolism in oleic acid and palmitic acid (OAPA)-treated HepG2 cells were measured. The expression of essential genes and proteins involved in lipid metabolism and autophagy signalings were measured to uncover the underlying mechanism.@*RESULTS@#Five compounds, including aurantio-obtusin, rubrofusarin gentiobioside, cassiaside C, emodin and rhein were simultaneously identified in CS extract. CS not only improved the diet-induced hepatic steatosis in vivo, as indicated by decreased number and size of lipid droplets, hepatic and serum triglycerides (TG) levels, but also markedly attenuated the OAPA-induced lipid accumulation in hepatocytes. These lipid-lowering effects induced by CS were largely dependent on the inhibition of fatty acid synthase (FASN) and the activation of autophagy-related signaling, including AMP-activated protein kinase (AMPK), light chain 3-II (LC3-II)/ LC3-1 and autophagy-related gene5 (ATG5).@*CONCLUSION@#Our study suggested that CS effectively protected liver steatosis via decreasing FASN-related fatty acid synthesis and activating AMPK-mediated autophagy, which might become a promising therapeutic strategy for relieving NAFLD.

Potent and Selective Inhibition of CYP1A2 Enzyme by Obtusifolin and Its Chemopreventive Effects.

Obtusifolin, a major anthraquinone component present in the seeds of Cassia tora, exhibits several biological activities, including the amelioration of memory impairment, prevention of breast cancer metastasis, and reduction of cartilage damage in osteoarthritis. We aimed to evaluate the inhibitory effects of obtusifolin and its analogs on CYP1A enzymes, which are responsible for activating procarcinogens, and investigate its inhibitory mechanism and chemopreventive effects. P450-selective substrates were incubated with human liver microsomes (HLMs) or recombinant CYP1A1 and CYP1A2 in the presence of obtusifolin and its four analogs. After incubation, the samples were analyzed using liquid chromatography-tandem mass spectrometry. Molecular docking simulations were performed using the crystal structure of CYP1A2 to identify the critical interactions between anthraquinones and human CYP1A2. Obtusifolin potently and selectively inhibited CYP1A2-mediated phenacetin O-deethylation (POD) with a Ki value of 0.031 µM in a competitive inhibitory manner in HLMs, whereas it exhibited negligible inhibitory effect against other P450s (IC50 > 28.6 µM). Obtusifolin also inhibited CYP1A1- and CYP1A2-mediated POD and ethoxyresorufin O-deethylation with IC50 values of <0.57 µM when using recombinant enzymes. Our molecular docking models suggested that the high CYP1A2 inhibitory activity of obtusifolin may be attributed to the combination of hydrophobic interactions and hydrogen bonding. This is the first report of selective and potent inhibitory effects of obtusifolin against CYP1A, indicating their potential chemopreventive effects.

Simultaneous determination of seven anthraquinones in Cassiae semen by natural deep eutectic solvent extraction.

INTRODUCTION: Anthraquinones are considered to be an important class of bioactive substances in Cassiae semen, and the content of anthraquinones is an essential indicator of the quality of Cassiae semen raw herbal materials. OBJECTIVES: The present study aimed to propose a novel, efficient and effective ultra-high-performance liquid chromatography (UHPLC) method for the simultaneous determination of aurantio-obtusin, aloe-emodin, rhein, obtusin, emodin, chrysophanol and physcion, with the help of natural deep eutectic solvents (NADESs) as extraction solvents. METHODOLOGY: NADESs were introduced to the simultaneous extraction of anthraquinones from Cassiae semen samples. Several NADESs were designed by menthol, choline chloride, d-glucose as hydrogen bond acceptors, with nine different acids and appropriate water as hydrogen bond donors. The parameters affecting the extraction efficiency of seven anthraquinones were demonstrated in detail. RESULTS: Among the obtained NADESs, the highest extraction efficiency was demonstrated by a solution consisting of d-glucose, lactic acid and water with a molar ratio of 1:5:4. The seven anthraquinones were separated on an ACQUITY UPLC® BEH C18 column (2.1 mm × 100 mm, 1.8 µm) and detected within 12 min by a photodiode array (PDA) detector at 254 and 284 nm. The limits of detection and quantitation were from 1.00 to 7.26 µg/l and 3.29 to 24.22 µg/l, respectively. And Cassiae semen sample-based recoveries ranged from 81.13% to 113.78% with the relative standard deviation (RSD) (n = 6) of 1.4% to 10.1%. CONCLUSION: The developed method demonstrated that NADESs were applied successfully to analyse the anthraquinones in Cassiae semen samples collected from different regions in China.

Predicting the potential toxicity of 26 components in Cassiae semen using in silico and in vitro approaches.

Cassiae semen are dried and ripe seeds of Cassia obtusifolia L. or Cassia tora L. (Fabaceae) and have been made into roasted tea or used as a traditional medicine in Asian countries. However, it was reported to result in liver and renal toxicity. The components of Cassiae semen that induce hepatotoxicity or nephrotoxicity remain unknown. In the present study, we evaluate the potential toxicity of 26 newly isolated compounds from Cassiae semen using quantitative structure-activity relationship (QSAR) methods and co-culture of hepatic and renal cell approaches, and we aim to illustrate the relationship between the structural characteristics and cytotoxicity by general linear models (GLMs). Both the QSAR models and co-culture of hepatic and renal cell systems predicted that 6 compounds were potentially hepatotoxic, 10 compounds were potentially nephrotoxic, and specific anthraquinones and anthraquinone-glucosides were potential toxicants in Cassiae semen. Specific groups such as -OH and -OCH3 at the R1, R2, R3, and R7 positions influenced the cytotoxicity.

Investigation on the stability in plant metabolomics with a special focus on freeze-thaw cycles: LC-MS and NMR analysis to Cassiae Semen (Cassia obtusifolia L.) seeds as a case study.

Metabolomics is a rapid and sensitive tool for the detection of dynamic metabolic compositions in the study of systemic metabolic consequences. However, it is also susceptible to a tiny variation of pre-analytical handling procedures. To provide reproducible results, specific knowledge on metabolites perturbance along with different freeze-thaw cycles (FTCs) is needed for further metabolomics studies. In this paper, five FTCs of germinated Cassiae Semen (CS) were chosen as a case study to investigate the influence of FTC effect based on UHPLC-Q-Orbitrap-MS and NMR technologies. A total of 108 metabolites were relatively quantified by LC-MS and NMR analyses. Principal component analysis (PCA) showed that the first and second FTC samples are welly separated from the other groups; however, the extent of FTC-induced effects are smaller after the third cycle. Upon five consecutive FTCs, alterations which consisted of decreased stachyose, sucrose, norrubrofusarin-6-O-ß-d-glucopyranoside, and quercetin 3-(3″-acetylgalactoside), as well as increased phenylalanine, leucine, isoleucine, methionine, phenylalanine, mannose, gluconic acid, and valine, could be observed. FTC does not exert the same effect on all metabolites. Although a large number of secondary metabolites were stable when subjected to five FTCs, FTC effects may lead to false-positive in the discovery of biomarker. In the case of reusing plant seed samples, no more than three consecutive freeze-thaw cycles were found advisable. This work provides unique perspectives on the FTC effects, which may fill in some existing gaps in the knowledge of the stability of plant metabolites during sample pre-handling.

[Research on revision of origins to Chinese medicinal materials in 2020 edition of Chinese pharmacopoeia].

The origins of 9 species of the Chinese medicinal materials in the 2015 edition of the Chinese pharmacopoeia(ChP) has revised in the 2020 edition of ChP. The revision is based on the investigation and textual research on the problems found after screening the original plants, animals or minerals of all the Chinese medicinal materials in the 2015 edition. Among them the Chinese names of Alismatis Rhizoma, Cassiae Semen, Coicis Semen, Corydalis Bungeanae Herba and Echinopsis Radix all do not match to the Latin scientific names, and also do not match the name of the actual medicinal origins. In addition, Alismatis Rhizoma has the omission of original plant. There is confusion about the Chinese name and the family name of the original insect of Cera Chinensis. The original mineral of Gypsum Fibrosum has the wrong group names. Alumstone and melanterite, the original mineral of Alumen and Melanteritum respectively, of which the group names are missing. To solve these problems, field survey and literature research were conducted on the medicinal materials and their origins. The source of these problems are explored. The correct origins and the Chinese names or Latin names are all determined according to the research results to the situation, in which the Chinese and Latin names of the original plants of the medicinal materials do not match. The correct family name and group name are obtained through textual research by taxonomy if the names are confused or mis-sing. The scientific evidence and correct results of revision in the 2020 edition of ChP are determined at last.

How does traditional knowledge of Cassiae semen shed light on weight management? - A classical and modern literature review.

ETHNOPHARMACOLOGICAL RELEVANCE: The seed of Senna obtusifolia (L.) H. S. Irwin & Barneby (Cassiae semen, CS) also known as Jue ming zi in China, has been traditionally used for weight management by purging the liver and improving the liver functions to support digestion. In the past decades, it has been used for hepatoprotection and treatment of overweight and other metabolic disorders such as hyperlipidaemia and diabetes. AIM OF THE REVIEW: This review aimed at providing comprehensive information on the traditional usages, pharmacology, phytochemistry and toxicology of CS and critically exploring its potential usage for clinical weight management from both traditional and modern application perspectives. MATERIALS AND METHODS: In order to fully understand the properties, actions and indications of CS, two sets of Chinese classical texts were searched, namely: Zhong Hua Yi Dian (Encyclopedia of Traditional Chinese Medicine) and Zhong Guo Ben Cao Quan Shu (Complete Collection of Traditional Texts on Chinese Materia Medica). The purpose of studying these classical texts was to determine the traditional use of CS in weight management. Comprehensive searches were also performed on seven databases for publications on original randomised clinical trials (RCT), in vivo, in vitro or in silico studies related to pharmacological effects of CS. Detailed information about the phytochemistry of CS was collected from books, encyclopedia, online databases and journal literature. FINDINGS: In classical literature review, 89 classic texts provided information of properties, actions and indications of CS. In modern literature review, 44 studies were included for analysis, including 5 RCTs, 7 in vivo studies, 14 in vitro studies, 2 in silico studies and 16 studies of mixed types. Chinese classic literature has provided traditional evidence of the usage of CS for weight management. Contemporary studies have revealed that CS has weight loss effects and possesses some other pharmacological activities supporting weight management. Some chemical compounds of CS have been hypothesised to have a direct or indirect contribution to weight control. CONCLUSIONS: The relationships between chemical compounds and the corresponding weight-loss target proteins are not fully understood. Therefore, CS constituents should be further explored for the development of novel therapeutic or preventive agents for the treatment of overweight and obesity.

Research on revision of origins to Chinese medicinal materials in 2020 edition of Chinese pharmacopoeia / 中国中药杂志

The origins of 9 species of the Chinese medicinal materials in the 2015 edition of the Chinese pharmacopoeia(ChP) has revised in the 2020 edition of ChP. The revision is based on the investigation and textual research on the problems found after screening the original plants, animals or minerals of all the Chinese medicinal materials in the 2015 edition. Among them the Chinese names of Alismatis Rhizoma, Cassiae Semen, Coicis Semen, Corydalis Bungeanae Herba and Echinopsis Radix all do not match to the Latin scientific names, and also do not match the name of the actual medicinal origins. In addition, Alismatis Rhizoma has the omission of original plant. There is confusion about the Chinese name and the family name of the original insect of Cera Chinensis. The original mineral of Gypsum Fibrosum has the wrong group names. Alumstone and melanterite, the original mineral of Alumen and Melanteritum respectively, of which the group names are missing. To solve these problems, field survey and literature research were conducted on the medicinal materials and their origins. The source of these problems are explored. The correct origins and the Chinese names or Latin names are all determined according to the research results to the situation, in which the Chinese and Latin names of the original plants of the medicinal materials do not match. The correct family name and group name are obtained through textual research by taxonomy if the names are confused or mis-sing. The scientific evidence and correct results of revision in the 2020 edition of ChP are determined at last.

Phytochemicals containing biologically active polyphenols as an effective agent against Covid-19-inducing coronavirus.

The outbreak of Covid-19 disease caused by SARS-CoV-19, along with the lack of targeted medicaments and vaccines, forced the scientific world to search for new antiviral formulations. In this review, we describe the current knowledge about plant extracts containing polyphenols that inhibit Covid-19. Many plant-derived natural compounds (polyphenols) might provide a starting point for the research on the use of plant extracts in coronavirus treatment and prevention. Antivirus polyphenolic drugs can inhibit coronavirus enzymes, which are essential for virus replication and infection. This group of natural substances (betulinic acid, indigo, aloeemodine, luteolin, and quinomethyl triterpenoids, quercitin or gallates) is a potential key to designing antiviral therapies for inhibiting viral proteases. The known pharmacophore structures of bioactive substances can be useful in the elaboration of new anti-Covid-19 formulations. The benefit of using preparations containing phytochemicals is their high safety for patients and no side effects.

Characterizing fungal communities in medicinal and edible Cassiae Semen using high-throughput sequencing.

Cassiae Semen (CS) has been widely used as roasted tea and traditional Chinese medicine for decades. However, CS is easily contaminated by fungi and mycotoxins during pre-harvest and post-harvest process, thus posing a potential threat to consumer health. In this study, we used the Illumina MiSeq PE300 platform and targeted the internal transcribed spacer 2 sequences to survey the occurrence of fungi in raw and roasted CS samples. Results showed the fungal contamination in all 12 test samples. Ascomycota was the prevailing fungus at the phylum level, with the relative abundance of 66.50%-99.42%. At the genus level, Aspergillus, Cladosporium, and Penicillium were the most dominant genera, accounting for 0.66%-85.51%, 0.20%-29.11%, and 0.11%-32.92% of the fungal reads, respectively. A total of 68 species were identified, among which six potential toxigenic fungi belonging to Aspergillus, Penicillium, Candida, and Schizophyllum genera were detected. Moreover, differences in fungal communities were observed in raw and roasted CS samples. In conclusion, amplicon sequencing is feasible for analyzing fungal communities in CS samples, which provides a new approach to investigate the fungal contamination in edible-medicinal herb, thereby ensuring food safety and drug efficacy.

Anthraquinones in the aqueous extract of Cassiae semen cause liver injury in rats through lipid metabolism disorder.

BACKGROUND: Cassiae semen has been used as the tea or medicine component to treat hyperlipidemia or for hepatoprotection. However, Cassiae semen was reported to be a potentially hepatotoxic herb, and the underlying hepatotoxicity mechanisms or specific hepatotoxic components of Cassiae semen are unknown. PURPOSE: In this study, we aimed to explore the potential hepatotoxicity mechanisms and the hepatotoxic components of Cassiae semen. METHODS: Both young adult male and female SD rats were orally administrated with the aqueous extract of the seeds of Senna obtusifolia (L.) H.S.Irwin & Barneby at doses of 4.73, 15.75, 47.30 g/kg for 28 days, and the body weight, liver coefficient, bile acids, histopathology, serum levels of TC, TG, LDL, HDL, ALP, ALT, AST, and LDH were examined. Lipidomic analysis of rat serum was performed by LC-MS to investigate the specifically changed lipids caused by the aqueous extract treatment. The components absorbed in plasma were detected by UHPLC-Q-Exactive-MS. MTT assay was used to evaluate the cytotoxicity of these components absorbed in plasma. RESULTS: The serum levels of ALP, AST, ALT, LDH were increased on day 7 with some of which gradually dropped to normal level on day 28. In high dose of the aqueous extract treated group, the histopathological changes were observed based on the cytoplasmic vacuolation in the liver and the increase of bile acids, indicating the hepatotoxicity of the aqueous extract. The changes of TC, TG, LDL, HDL indicated the disorder of lipid metabolism. By comparing the difference in lipids between high dose group and control group, the results showed that the alterations were primarily focused on glycerophospholipid metabolism in both male and female rats. In addition, the glycerolipid metabolism in female rats also changed. Further analyses found that PC (18:2/20:4) and LysoPC 18:0 were significantly increased. Among these phytochemicals detected in plasma, nine components in the aqueous extract were considered to have the highest concentrations, particularly some types of anthraquinones (AQs) existing in Cassiae semen (AQs-in-CS), such as obtusifolin, aurantio-obtusin, and obtusin. The MTT assay showed that emodin, obtusifolin, rhein, aurantio-obtusin, and obtusin inhibited cell viability. Considering plasma concentrations and cytotoxicity of these components, our study indicates that the AQs-in-CS (obtusifolin, aurantio-obtusin and obtusin), emodin and rhein are the potential hepatotoxic phytochemicals in the aqueous extract.

[UPLC-MS~n analysis and certification evaluation of main chemical composition in naphthopyrone reference extract of Cassiae Semen].

The main chemical constituents of naphthopyrone reference extract( NRE) with definite content and relatively fixed chemical composition were analyzed and determined. Ultra-high performance liquid chromatography-LTQ-Orbitrap XL mass spectrometry and high performance liquid chromatography were used to systematically study NRE from the aspects of main chemical components and determination. The results showed that the chemical composition of naphthopyrone reference extract of Cassiae Semen was relatively fixed,and seven naphthalopyranones were identified. Cassiaside B_2,cassiaside C_2,rubrofusarin-6-O-ß-D-gentiobioside and cassiaside C were the main chemical constituents of NRE,of which the determination and uncertainty results were( 11. 40+ 0. 26) %,( 11. 68+0. 24) %,( 16. 60+0. 22) %,( 28. 8+0. 48) %,respectively. This study contributed to the accurate evaluation of NRE and the foundation for the application of NRE in the quality control of Cassiae Semen,and provided a new idea for the replacement of single chemical reference substance by the reference extract of traditional Chinese medicine.

Anthraquinones from Cassiae semen as thrombin inhibitors: in vitro and in silico studies.

Thrombin inhibitor therapy is one of the most effective therapeutic strategies for the prevention and treatment of cardiovascular and thrombotic diseases. Although several marketed direct thrombin inhibitors (DTIs) have been widely used in clinic, the potentially serious complications of these DTIs prompted the researchers to find more DTIs with improved safety profiles. Herein, we report that natural anthraquinones in Cassiae semen (the seed of Cassia obtusifolia L. or C. tora L.), including obtusifolin, obtusin, aurantio-obtusin and chryso-obtusin, display strong to moderate inhibition on human thrombin, with the IC50 values ranging from 9.08 µM to 27.88 µM. Further investigation on the inhibition kinetics demonstrates that these anthraquinones are mixed inhibitors against thrombin-mediated Z-GGRAMC acetate hydrolysis, while obtusifolin and aurantio-obtusin show strong thrombin inhibition capacity, with the Ki values of 9.63 µM and 10.30 µM, respectively. Docking simulations demonstrate that both obtusifolin and aurantio-obtusin can simultaneously bind on the catalytic cavity and the two anion binding exosites (ABE1 and ABE2), while the hydroxyl group at the C-7 site and the methoxyl group at the C-8 site can create key interactions with the amino acids surrounding the catalytic cavity via hydrogen bonding. All these findings suggest that obtusifolin and aurantio-obtusin are strong thrombin inhibitors possessing a unique anthraquinone skeleton, and could be used as lead compounds for the development of new thrombin inhibitors with improved properties.