Structures and Biological Evaluation of Monoterpenoid Glycosides from the Roots of Paeonia lactiflora

A review of the ethnopharmacology, phytochemistry, pharmacology, pharmacokinetics and quality control of Paeonia lactiflora Pall

ETHNOPHARMACOLOGICAL RELEVANCE

Paeonia lactiflora Pall. (called Shaoyao in China) is a common herb cultivated all over the world. In some Asian and European countries, such as China, Japan, South Korea and Britain, P. lactiflora has a long history of ethnomedical uses, which is widely used to relieve pain, treat gynecological diseases, anti-infection and so on. It is attributed to the extensive pharmacological activities of total glucosides of P. lactiflora. Up to now, it is still commonly used in clinical medicine.

THE AIM OF THE REVIEW

The paper aims to make a comprehensive review on the botanical characterization and distribution, ethnopharmacology, phytochemistry, biosynthesis pathway, pharmacology, pharmacokinetics and quality control of P. lactiflora, so as to provide new insights and scientific evidence for the subsequent research.

MATERIALS AND METHODS

The information of P. lactiflora was obtained from books related to traditional Chinese medicine and electronic databases, including Scifinder, PubMed, Web of Science, CNKI and Google Scholar.

RESULTS

P. lactiflora is a kind of herb with a long history and it is used for medicine, food and ornamental, and shows high utilization value. There are 200 compounds have been identified from it, including terpenoids, flavonoids, polyphenols, organic acids and others, among those paeoniflorin, a monoterpenoid glycoside, has multiple activities and is currently the focus of pharmacological research. A great deal of pharmacological experiments supported the anti-inflammatory, anti-oxidant, hepatoprotective, neuroprotective, antibacterial, antitumor, dermatosis treating and other effects of P. lactiflora. In addition, evaluating the quality of P. lactiflora is essential to safe use of drug in humans.

CONCLUSIONS

The chemical components of P. lactiflora are diverse and have a wide range of activities. Modern pharmacological studies have provided reliable evidence for the traditional efficacy, such as suppressing liver yang, regulating menstruation and relieving pain. However, there are still some problems to be solved, such as part of the pharmacological mechanism has not been clarified and the biosynthetic pathway of cage-like monoterpenoids remains poorly defined. In addition, further studies on compounds other than paeoniflorin are clearly warranted. It is hoped that P. lactiflora will serve the clinic better in the future.

Oleanane and 30-noroleanane triterpenoids from the roots of Paeonia lactiflora

An investigation of EtOAc extract from the roots of Paeonia lactiflora yielded three new 30-noroleanane triterpenoids paeonenoides L-N (1-3) and one new oleanane triterpenoid paeonenoide O (4) together with 7 known compounds (5-11). Extensive spectrographic experiments were applied to identify the structures of 1-4, and their absolute configurations were unambiguously determined by theoretical calculations of ECD spectra, as well as the single-crystal X-ray diffraction analysis. Compounds 8, 9 and 10 were isolated from the Paeonia genus for the first time. Moreover, compounds 8, 9 and 11 showed inhibitory activities against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages with the IC50 values of 72. 17 ± 4.74, 30.02 ± 2.03 and 28.34 ± 1.85 μM, respectively.

Paeoniae Radix Rubra:A Review of Ethnopharmacology, Phytochemistry, Pharmacological Activities, Therapeutic Mechanism for Blood Stasis Syndrome, and Quality Control

Paeoniae Radix Rubra (PRR) known as Chishao, in China, is the dried root of Paeonia lactiflora Pall. or Paeonia veitchii Lynch, with a history of over 2000 years in traditional Chinese medicine, is employed to clear heat, cool the blood, dispel blood stasis, and alleviate pain. Phytochemical investigations identified 264 compounds that contained monoterpenes and their glycosides, sesquiterpenes, triterpenes, steroids, flavonoids, lignans, tannins, volatile oils, and other compounds. It has been reported to have different pharmacological activities, including cardiovascular-protective, antidepressive, neuroprotective, antitumor, hepatoprotective, and anti-inflammatory effects. This study offers a comprehensive review covering ethnopharmacology, phytochemistry, pharmacological activities, therapeutic mechanism for blood stasis syndrome, and quality control of PRR. The comprehensive analysis aims to achieve a thorough understanding of its effects and serves as a foundation for future research and development.

Two new acorane-type sesquiterpenoids from an endophytic Trichoderma harzianum associated with Paeonia lactiflora Pall

Two new acorane-type sesquiterpenoids, harzianes A and B (1 and 2), together with two known cyclonerodiol-type sesquiterpenoids (3-4) and four known sterols (5-8) were isolated from the endophytic Trichoderma harzianum, associated with the medicinal plant Paeonia lactiflora Pall. Compounds 1 and 2 were identified as a pair of heterotropic isomers by spectroscopic analysis (HR-ESI-MS, 1D and 2D NMR), and their absolute configurations were determined by ECD calculations. All compounds were tested for anti-inflammatory activity, however, none demonstrated such activity.

Illuminating the biosynthesis pathway genes involved in bioactive specific monoterpene glycosides in Paeonia veitchii Lynch by a combination of sequencing platforms

BACKGROUND

Paeonia veitchii Lynch, a well-known herb from the Qinghai-Tibet Plateau south of the Himalayas, can synthesize specific monoterpene glycosides (PMGs) with multiple pharmacological activities, and its rhizome has become an indispensable ingredient in many clinical drugs. However, little is known about the molecular background of P. veitchii, especially the genes involved in the biosynthetic pathway of PMGs.

RESULTS

A corrective full-length transcriptome with 30,827 unigenes was generated by combining next-generation sequencing (NGS) and single-molecule real-time sequencing (SMRT) of six tissues (leaf, stem, petal, ovary, phloem and xylem). The enzymes terpene synthase (TPS), cytochrome P450 (CYP), UDP-glycosyltransferase (UGT), and BAHD acyltransferase, which participate in the biosynthesis of PMGs, were systematically characterized, and their functions related to PMG biosynthesis were analysed. With further insight into TPSs, CYPs, UGTs and BAHDs involved in PMG biosynthesis, the weighted gene coexpression network analysis (WGCNA) method was used to identify the relationships between these genes and PMGs. Finally, 8 TPSs, 22 CYPs, 7 UGTs, and 2 BAHD genes were obtained, and these putative genes were very likely to be involved in the biosynthesis of PMGs. In addition, the expression patterns of the putative genes and the accumulation of PMGs in tissues suggested that all tissues are capable of biosynthesizing PMGs and that aerial plant parts could also be used to extract PMGs.

CONCLUSION

We generated a large-scale transcriptome database across the major tissues in P. veitchii, providing valuable support for further research investigating P. veitchii and understanding the genetic information of plants from the Qinghai-Tibet Plateau. TPSs, CYPs, UGTs and BAHDs further contribute to a better understanding of the biology and complexity of PMGs in P. veitchii. Our study will help reveal the mechanisms underlying the biosynthesis pathway of these specific monoterpene glycosides and aid in the comprehensive utilization of this multifunctional plant.

Paeoniflorin-free subfraction of Paeonia lactiflora Pall. shows the potential of anti-hepatic fibrosis: an integrated analysis of network pharmacology and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Hepatic fibrosis is a major consequence of liver disease. Radix Paeoniae Rubra (RPR), the dry root of Paeonia lactiflora Pall., has a long history of clinical application in traditional Chinese medicine (TCM) for the treatment of liver diseases. The researches of RPR active ingredients are mainly focused on paeoniflorin. However, the functional roles of other ingredients have not been clarified sufficiently in the treatment of hepatic fibrosis with RPR.

AIM OF THE STUDY

This study was to figure out the anti-hepatic fibrosis potential and mechanisms of CS-4, one of the paeoniflorin-free subfraction of RPR.

MATERIALS AND METHODS

With the guide of bioassay, CS-4, a subfraction of RPR showed in vitro inhibition of hepatic stellate cell activation, was obtained using multiple chromatographic techniques. Its ingredients were determined by UPLC-Q-TOF-MS/MS. Then, the target profiles of ingredients were obtained from the HERB database, and the disease targets were collected from the DisGeNET database. Through the network pharmacology method, a protein-protein interaction network of CS-4 against hepatic fibrosis was established to analyze and excavate the potential therapeutic targets. Combined with the KEGG analysis, a series of signaling pathways were obtained, thereby validated by western blot analysis.

RESULTS

The paeoniflorin-free subfraction of RPR, CS-4, was obtained and showed the most potential anti-fibrotic effect in vitro. A total of 20 main ingredients were identified from CS-4 and considered as its active ingredients. From HERB and DisGeNET databases, 1460 potential targets of CS-4 and 1180 disease targets were obtained, respectively. The overlapped 79 targets were considered to exert the potential anti-fibrosis effect of CS-4, such as JAK2, MYC, SMAD3, and IFNG. The gene enrichment analysis revealed that classical TGF-β/Smad signaling pathway and nonclassical TGF-β/PI3K-AKT signaling pathway may be two of the main mechanisms of CS-4 against hepatic fibrosis, which supported by western blot analysis.

CONCLUSION

In this study, a paeoniflorin-free subfraction with potential anti-hepatic fibrosis activity in vitro, CS-4, was obtained from RPR. Its multiple ingredients, multiple targets, and multiple mechanisms against hepatic fibrosis were explained by network pharmacology and verified by western blot analysis to further support the clinical applications of RPR.

Screening of Biomarkers and Quality Control of Shaoyao Gancao Decoction Using UPLC-MS/MS Combined with Network Pharmacology and Molecular Docking Technology

Shaoyao Gancao Decoction (SGD) is a classic prescription of traditional Chinese medicine (TCM), which is composed of Paeoniae Radix Alba and Glycyrrhizae Radix et Rhizoma, and has the clinical effect of anti-liver injury, but its active ingredients are unclear. In this study, the joint application of phytochemical compositional analysis, network pharmacology, and molecular docking technology was utilized to screen the active components of SGD against liver injury. Firstly, a total of 110 compounds were identified by UPLC-Q-TOF-MS/MS, including 54 flavonoids, 23 triterpenoids, 10 monoterpenoids, 6 coumarins, and 17 other compounds. Secondly, based on the above plant chemical compositions, network pharmacology was used to search for the active components of SGD against liver injury, and 19 components were considered to be the active components, including 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose, ferulic acid, coniferyl ferulate, benzoyl paeoniflorin, hesperidin, liquiritin, liquiritigenin, glycyrrhizic acid, caffeic acid, rutin, chlorogenic acid, gallic acid, methyl gallate, isoliquiritin apioside, albiflorin, neochlorogenic acid, isoliquiritin, narirutin, and naringenin. Thirdly, molecular docking was used to verify the efficacy of the compounds and showed that the compounds bound well to key targets. Furthermore, the 19 components were detected in the rat serum, which also demonstrated that they could be biomarkers. Because it is generally believed that the ingredients that can be absorbed into the blood may be active ingredients. In the end, we determined the contents of 19 key components in 10 different batches of SGD. The method has satisfactory linearity, stability, accuracy, repeatability, and recovery. This study clarified the active components, key targets, and pathways of SGD against liver injury and provided a new idea for the selection of quality control indicators in traditional Chinese medicine.

Multiple anti-non-alcoholic steatohepatitis (NASH) efficacies of isopropylidenyl anemosapogenin via farnesoid X receptor activation and TFEB-mediated autophagy

BACKGROUND

Non-alcoholic steatohepatitis (NASH) can develop into cirrhosis, liver failure, or hepatocellular carcinoma without effective treatment. However, there are currently no drugs for NASH treatment, and the development of new therapeutics has remained a major challenge in NASH research. Advances in traditional Chinese medicine to treat liver disease inspired us to search for new NASH candidates from Chi-Shao, a widely used traditional Chinese medicine.

PURPOSE

In this research, we aimed to clarify the anti-NASH effect and the underlying mechanism of isopropylidenyl anemosapogenin (IA, 1), which was a new lead compound isolated from Chi-Shao.

STUDY DESIGN AND METHODS

Isopropylidenyl anemosapogenin (IA, 1) was first discovered by collagen type I α 1 promoter luciferase bioassay-guided isolation and then characterized by single crystal X-ray diffraction analysis and enriched by semi-synthesis. Using various molecular biology techniques, the multiple anti-NASH efficacies and mechanisms of IA were clarified based on in vitro LX-2 and Huh7 cell models, along with the in vivo choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD)-induced mouse model and bile duct ligation (BDL)-induced rat model. The UPLC-MS/MS method was used to assess the plasma concentration of IA.

RESULTS

A new lead compound IA was isolated from the traditional Chinese medicine Chi-Shao, which showed significant anti-liver fibrosis activity in TGF-β1-treated LX-2 cells and anti-liver steatosis activity in oleic acid-treated Huh7 cells. Furthermore, IA could significantly ameliorate in vivo CDAHFD-induced liver injury by activating the farnesoid X receptor pathway, including its targets Nr0b2, Abcb11, and Slc10a2. Simultaneously, IA activated the autophagy pathway by activating the TFEB factor, thereby promoting lipid degradation. Its liver-protective and anti-fibrosis activities were verified by the BDL-induced rat model. Finally, with an oral administration of 100 mg/kg, IA achieved the maximum plasma concentration of 1.23 ± 0.18 μg/ml at 2.67 ± 0.58 h.

CONCLUSION

IA, an unreported lupine-type triterpenoid isolated from Chi-shao, can significantly alleviate liver injury and fibrosis via farnesoid X receptor activation and TFEB-mediated autophagy, which indicates that IA could serve as a novel therapeutic candidate against NASH.

Anti-anaphylactic potential of benzoylpaeoniflorin through inhibiting HDC and MAPKs from Paeonia lactiflora

Guided by cell-based anti-anaphylactic assay, eighteen cage-like monoterpenoid glycosides (1-18) were obtained from the bioactive fraction of P. lactiflora extract. Among these, compounds 1, 5, 6, 11, 12, 15, and 17 significantly reduced the release rate of β-HEX and HIS without or with less cytotoxicity. Furthermore, the most potent inhibitor benzoylpaeoniflorin (5) was selected as the prioritized compound for the study of action of mechanism, and its anti-anaphylactic activity was medicated by dual-inhibiting HDC and MAPK signal pathway. Moreover, molecular docking simulation explained that benzoylpaeoniflorin (5) blocked the conversion of L-histidine to HIS by occupying the HDC active site. Finally, in vivo on PCA using BALB/c mice, benzoylpaeoniflorin (5) suppressed the IgE-mediated PCA reaction in antigen-challenged mice. These findings indicated that cage-like monoterpenoid glycosides, especially benzoylpaeoniflorin (5), mainly contribute to the anti-anaphylactic activity of P. lactiflora by dual-inhibiting HDC and MAPK signal pathway. Therefore, benzoylpaeoniflorin (5) may be considered as a novel drug candidate for the treatment of anaphylactic diseases.

Bioactive sesquineolignans from the twigs of Litsea cubeba

In a continuing search for biological natural products with structure diversity from traditional Chinese herbs, five new sesquineolignans (1-5) were isolated from an ethyl acetate extract of the twigs of Litsea cubeba. Their structures were elucidated based on MS, 1D and 2D NMR spectroscopic data, as well as experimental electronic circular dichroism (ECD) spectra. Compounds 1-5 showed moderate inhibitory effects against LPS-induced NO production in RAW264.7 macrophages, with IC₅₀ values of 16.2, 20.2, 22.1, 15.1, and 16.6 μmol·L^-1, respectively.

Antifungal and wound healing promotive compounds from the resins of Dracaena cochinchinensis

Five new compounds (xuejieins A-E), including three new phenolic glycosides (1, 2, and 5) and two new flavonoids (10 and 11), together with six known compounds were isolated from the resins of Dracaena cochinchinensis (Chinese dragon's blood). The structures of the new compounds were confirmed by extensive spectroscopic methods and electronic circular dichroism (ECD) data analysis. Especially, the absolute configurations of the sugar moieties in compounds 1, 2, and 5 were clarified by GC analysis after acid hydrolysis. All isolated compounds have been tested for antifungal and wound healing promoting activities, The results showed that compound 9 shows significant antifungal activities against Botrytis cinerea, Magnaporthe grisea, Penicillium digitatum, and Sclerotinia sclerotiorum. In addition, compound 4 could significantly stimulate human keratinocytes (HaCAT) proliferation, mobility, and human umbilical vein vascular endothelial cells (HUVECs) tube formation at 40 μM.

Paeonone A, a novel nonanortriterpenoid from the roots of Paeonia lactiflora

Paeonone A (1), a unique nonanortriterpenoid, and a new octanortriterpenoid, paeonone B (2), were isolated from the roots of Paeonia lactiflora, together with a known analogue, palbinone (3). Paeonone A (1) is the first example of naturally occurring nonanortriterpenoid with a diketo acid group. Extensive NMR and HRESIMS experiments were applied to identify the structures of 1 and 2, and their absolute configurations were solved by single-crystal X-ray diffraction and ECD data. Biological properties of 1-3 were explored against pancreatic lipase and cancer cell lines.

Bioactivity-Guided Discovery of Human Carboxylesterase Inhibitors from the Roots of Paeonia lactiflora

In a continuing search for potential inhibitors against human carboxylesterases 1A1 and 2A1 (hCES1A1 and hCES2A1), an EtOAc extract of the roots of Paeonia lactiflora showed strong hCES inhibition activity. Bioassay-guided fractionation led to the isolation of 26 terpenoids including 12 new ones (1-5, 7-12, and 26). Among these, sesquiterpenoids 1 and 6, monoterpenoids 10, 11, and 13-15, and triterpenoids 18-20, 22, and 24-26 contributed to the hCES2A1 inhibition, in the IC₅₀ range of 1.9-14.5 μM, while the pentacyclic triterpenoids 18-26 were responsible for the potent inhibitory activity against hCES1A1, with IC₅₀ values less than 5.0 μM. The structures of all the compounds were elucidated using MS and 1D and 2D NMR data, and the absolute configurations of the new compounds were resolved via specific rotation, experimental and calculated ECD spectra, and single-crystal X-ray diffraction analysis. The structure-activity relationship analysis highlighted that the free HO-3 group in the pentacyclic triterpenoids is crucial for their potent inhibitory activity against hCES1A1.

The bioactive compounds and cellular antioxidant activity of Herbaceous peony (Paeonia lactiflora Pall) seed oil from China

Herbaceous peony (HP) seed oil has been consumed in some regions of China, yet little information is available on its bioactive composition and antioxidant activity. This study aimed to evaluate the fatty acid compositions, micronutrients contents, and cellular antioxidant activity (CAA) of HP seed oil from five varieties. Results indicated that this oil had high percentages of monounsaturated (32.15 to 45.92%) and polyunsaturated fatty acids (58.65 to 61.95%), and the α-linolenic acid C18:3 was the highest in Fushao seed oil. Additionally, the high concentrations of tocopherol and phytosterol were found in all seed oils, and 10 individual polyphenols have been evaluated. Fushao seed oil had the highest polyphenols levels and showed higher CAA values. Both hierarchical cluster analysis and principal component analysis have been used to distinguish HP seed oil from different varieties. This information is valuable for the nutritional value and industrial interest of HP seed oil in China. PRACTICAL APPLICATION: This research showed that Herbaceous peony seed oil had higher levels of minor components and polyunsaturated fatty acids, especially, α-linolenic acid, and our results could also provide the theoretical foundation for the health benefits of Herbaceous peony seed oil as the vegetable oils. However, the variety of Herbaceous should be considered when extracting oil from Herbaceous peony seeds in the industry.

Triterpene saponins from the seeds of Erythrophleum fordii and their cytotoxic activities

Erythrosides A-G, seven undescribed oleanane-type triterpenoid saponins, were isolated from the seeds of Erythrophleum fordii. Their structures with absolute configurations were determined by extensive spectroscopic analysis including one-dimensional [1D] and two-dimensional [2D] nuclear magnetic resonance [NMR], high-resolution electrospray ionization mass spectroscopy [HR-ESI-MS] analysis, and chemical methods. Erythrosides A-G featured a diverse oligosaccharide chain containing 4-6 pentoses or hexoses at C-3 and a monoterpenic acid or a (E)-cinnamic acid unit at the C-21 position. Of particular interest, erythrosides A-C, E and F contained a rare alpha xylose in their sugar chains. The bioassay results indicated that erythrosides A-C showed moderate cytotoxic activities against human lung cancer cell line PC9 with IC₅₀ values of 13.14, 16.67 and 17.59 μM, respectively (the positive control, Taxol, IC₅₀ = 0.60 nM).

Survey of natural products reported by Asian research groups in 2018

The new natural products reported in 2018 in peer-reviewed articles in journals with good reputations were reviewed and analyzed. The advances made by Asian research groups in the field of natural products chemistry in 2018 were summarized. Compounds with unique structural features and/or promising bioactivities originating from Asian natural sources were discussed based on their structural classification.

Anti-inflammatory glycosides from the roots of Paeonia intermedia C. A. Meyer

Three new phenolic glycosides, intermedia A-C (1-3), one new acyclic alcohol glycoside, intermedia D (4), together with 3 known glycosides (5-7), were isolated from the dried roots of Paeonia intermedia C. A. Meyer. Their structures were established by means of extensive spectroscopic analysis (HRESIMS, NMR). Compound 1 have a rare benzo[1,5]dioxepine skeleton. The bioassay results showed that compound 3 exhibited inhibitory activity against proinflammatory cytokines nitric oxide (NO) secretion in LPS-activated RAW264.7 cells with an IC₅₀ value of 85.76 ± 1.36 μM.