Polyphenols with anti-proliferative activities from Penthorum chinense Pursh

Activity of thonningianin A against Candida albicans in vitro and in vivo

Fungal infections are increasing rapidly, and antifungal agents used in clinics are limited. Therefore, novel antifungal agents with high efficiency are urgently required. In this study, we investigated the antifungal activity of thonningianin A (THA), a natural compound that is widely found in plants. We first determined the activity of THA against Candida albicans, one of the most common fungal pathogens, and found that THA showed antifungal activity against all C. albicans tested, including several fluconazole-resistant isolates. THA also inhibits the growth of non-Candida albicans species. In addition, THA displayed antibiofilm activity and could not only inhibit biofilm formation but also destroy mature biofilms. The in vivo antifungal efficacy of THA was confirmed in a Galleria mellonella infection model. Further studies revealed that THA could enhance intracellular reactive oxygen species (ROS) production and regulate the transcription of several redox-related genes. Specifically, caspase activity and expression of CaMCA1, a caspase-encoding gene in C. albicans, were remarkably increased upon THA treatment. Consistent with this, in the presence of THA, the Camca1 null mutant displayed higher survival rates and reduced caspase activity compared to the wild-type or CaMCA1-reintroduced strains, indicating an important role of CaMCA1 in the antifungal activity of THA. Taken together, our results indicate that THA possesses excellent antifungal activity and may be a promising novel antifungal candidate. KEY POINTS: • THA exhibits activity against Candida species, including fluconazole-resistant isolates • THA inhibits biofilm formation and destroys mature biofilm • Elevated ROS production and CaMCA1-mediated caspase activity are involved in the antifungal mechanisms of THA.

Plant flavonoid inhibition of SARS-CoV-2 main protease and viral replication

Plant-based flavonoids have been evaluated as inhibitors of β-coronavirus replication and as therapies for COVID-19 on the basis of their safety profile and widespread availability. The SARS-CoV-2 main protease (Mpro) has been implicated as a target for flavonoids in silico. Yet no comprehensive in vitro testing of flavonoid activity against SARS-CoV-2 Mpro has heretofore been performed. We screened 1,019 diverse flavonoids for their ability to inhibit SARS-CoV-2 Mpro. Multiple structure-activity relationships were identified among active compounds such as enrichment of galloylated flavonoids and biflavones, including multiple biflavone analogs of apigenin. In a cell-based SARS-CoV-2 replication assay, the most potent inhibitors were apigenin and the galloylated pinocembrin analog, pinocembrin 7-O-(3''-galloyl-4'',6''-(S)-hexahydroxydiphenoyl)-beta-D-glucose (PGHG). Molecular dynamic simulations predicted that PGHG occludes the S1 binding site via a galloyl group and induces a conformational change in Mpro. These studies will advance the development of plant-based flavonoids-including widely available natural products-to target β-coronaviruses.

Effect of Penthorum Chinense Pursh Compound on AFB1-Induced Immune Imbalance via JAK/STAT Signaling Pathway in Spleen of Broiler Chicken

Aflatoxin B1(AFB1) is the main secondary metabolite produced by Aspergillus flavus, which is highly toxic, carcinogenic, mutagenic and teratogenic. It can induce immune imbalance in animals or humans. Penthorum chinense Pursh (PCP) is a traditional herbal plant that has been used as a hepatoprotective drug with a long history in China. Based on the theory of traditional Chinese Medicine, we prepared Penthorum chinense Pursh Compound (PCPC) by combining four herbal medicines: 5 g Penthorum chinense Pursh, 5 g Radix bupleuri, 1 g Artemisia capillaris Thunb and 1 g Radix glycyrrhizae. The role of the Penthorum chinense Pursh Compound (PCPC) in preventing AFB1-induced immune imbalance in broiler chickens was studied. A total of 180 broiler chickens were equally distributed in six groups: controls, AFB1, YCHD and high-, medium- and low-dose PCPC treatment groups. After 28 days, broilers were anesthetized, and serum spleen and thymus samples were collected for analysis. Results show that AFB1 significantly increased and decreased the relative organ weight of the spleen and thymus, respectively. Pathological section of hematoxylin/eosin (H&E) stained spleen sections showed that AFB1 resulted in splenic tissue damage. Both the serum levels of Immunoglobulin A (IgA) and Immunoglobulin G (IgG) were suppressed in the AFB1 group. IL-6 was elevated in the AFB1 group. The balance between pro-inflammatory cytokines (IFN-γ and IL-2) and anti-inflammatory cytokine (IL-4) was disturbed by AFB1. The apoptosis-related protein and JAK/STAT pathway-related gene expression indicated that AFB1-induced apoptosis via JAK/STAT pathway. PCPC has proven its immunoprotective effects by preventing AFB1-induced immune imbalance. PCPC can be applied as a novel immune-modulating medicine in broiler chickens. It can be applied as a novel immune modulator in veterinary clinical practice.

Cytotoxicity and Identification of Antibacterial Compounds from Baillonella toxisperma Bark Using a LC-MS/MS and Molecular Networking Approach

Baillonella toxisperma is a medicinal plant used in northern Gabon to treat microbial diseases. It is a plant well-known by local populations, but very few studies have focused on the molecules responsible for the antibacterial activities of B. toxisperma. This study proposes a dereplication strategy based on molecular networking generated from HPLC-ESI-Q/TOF data, allowing investigation of the molecules responsible for the antibacterial activity of B. toxisperma. From this strategy, eighteen compounds were putatively identified. All of these compounds belonged mainly to five families of natural compounds, including phenylpropanolamines, stilbenes, flavonoids, lignans and phenolic glycosides. The chemical study carried out from the bark of B. toxisperma allowed us to identify, for the first time, compounds such as resveratrol and derivatives, epicatechin, epigallocatechin and epigallocatechin gallate. In addition, antibacterial activity (diffusion method and microdilution) and cytotoxicity (Cell Counting Kit-8 (CCK-8 Assay)) in vitro were evaluated. The crude ethanolic extract, as well as the fractions of B. toxisperma, showed significant antibacterial activity. However, the ethanolic fractions F2 and F4 presented high antibacterial activity compared to the crude extract. Cytotoxicity studies on colon-cancer cells (Caco-2) and human keratinocyte cells (HaCaT) showed moderate cytotoxicity in both cell types. This study clearly shows the therapeutic potential of the ethanolic extract of the bark of B. toxisperma and provides information on the phytochemical composition and bioactive compounds of the plant.

An Updated Review on Efficiency of Penthorum chinense Pursh in Traditional Uses, Toxicology, and Clinical Trials

Traditional Chinese medicines (TCM) play an important role in the control and treatment of several animal diseases. Penthorum chinense Pursh (PCP) is a famous plant for its use in traditional medication practice and therapeutic effects in numerous pathological conditions. In China, PCP is utilized for both food and medication due to numerous bioactivities. PCP is widely administered in prevention and treatment of traumatic injury, edema, and liver diseases with functions of reducing swelling, support diuresis, blood stasis, and mitigation symptoms of excessive alcohol intake. Recently, PCP highlighted for research trials in various fields including pharmacology, pharmacognosy, cosmeceuticals, nutraceuticals, and pharmaceuticals due to medicinal significance with less toxicity and an effective ethnomedicine in veterinary practice. PCP contains diverse important ingredients such as flavonoids, organic acids, coumarins, lignans, polyphenols, and sterols that are important bioactive constituents of PCP exerting the therapeutic benefits and organ-protecting effects. In veterinary, PCP extract, compound, and phytochemicals/biomolecules significantly reversed the liver and kidney injuries, via antioxidation, oxidative stress, apoptosis, mitochondrial signaling pathways, and related genes. PCP water extract and compounds also proved in animal and humans' clinical trial for their hepatoprotective, antiaging, nephroprotective, anti-inflammatory, antidiabetic, antibacterial, antiapoptotic, immune regulation, and antioxidative stress pathways. This updated review spotlighted the current information on efficiency and application of PCP by compiling and reviewing recent publications on animal research. In addition, this review discussed the toxicology, traditional use, comparative, and clinical application of PCP in veterinary practices to authenticate and find out new perspectives on the research and development of this herbal medicine.

Targeting microglial autophagic degradation of the NLRP3 inflammasome for identification of thonningianin A in Alzheimer’s disease

Background

NLRP3 inflammasome-mediated neuroinflammation plays a critical role in the pathogenesis and development of Alzheimer’s disease (AD). Microglial autophagic degradation not only decreases the deposits of extracellular Aβ fibrils but also inhibits the activation of NRLP3 inflammasome. Here, we aimed to identify the potent autophagy enhancers from Penthorum chinense Pursh (PCP) that alleviate the pathology of AD via inhibiting the NLRP3 inflammasome.

Methods

At first, autophagic activity-guided isolation was performed to identify the autophagy enhancers in PCP. Secondly, the autophagy effect was monitored by detecting LC3 protein expression using Western blotting and the average number of GFP-LC3 puncta per microglial cell using confocal microscopy. Then, the activation of NLRP3 inflammasome was measured by detecting the protein expression and transfected fluorescence intensity of NLRP3, ASC, and caspase-1, as well as the secretion of proinflammatory cytokines. Finally, the behavioral performance was evaluated by measuring the paralysis in C. elegans, and the cognitive function was tested by Morris water maze (MWM) in APP/PS1 mice.

Results

Four ellagitannin flavonoids, including pinocembrin-7-O-[4″,6″-hexahydroxydiphenoyl]-glucoside (PHG), pinocembrin-7-O-[3″-O-galloyl-4″,6″-hexahydroxydiphenoyl]-glucoside (PGHG), thonningianin A (TA), and thonningianin B (TB), were identified to be autophagy enhancers in PCP. Among these, TA exhibited the strongest autophagy induction effect, and the mechanistic study demonstrated that TA activated autophagy via the AMPK/ULK1 and Raf/MEK/ERK signaling pathways. In addition, TA effectively promoted the autophagic degradation of NLRP3 inflammasome in Aβ(1–42)-induced microglial cells and ameliorated neuronal damage via autophagy induction. In vivo, TA activated autophagy and improved behavioral symptoms in C. elegans. Furthermore, TA might penetrate the blood-brain barrier and could improve cognitive function and ameliorate the Aβ pathology and the NLRP3 inflammasome-mediated neuroinflammation via the AMPK/ULK1 and Raf/MEK/ERK signaling pathways in APP/PS1 mice.

Conclusion

We identified TA as a potent microglial autophagy enhancer in PCP that promotes the autophagic degradation of the NLRP3 inflammasome to alleviate the pathology of AD via the AMPK/ULK1 and Raf/MEK/ERK signaling pathways, which provides novel insights for TA in the treatment of AD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41232-022-00209-7.

Integrated Chemical Interpretation and Network Pharmacology Analysis to Reveal the Anti-Liver Fibrosis Effect of Penthorum chinense

Liver fibrosis is a disease with complex pathological mechanisms. Penthorum chinense Pursh (P. chinense) is a traditional Chinese medicine (TCM) for liver injury treatment. However, the pharmacological mechanisms of P. chinense on liver fibrosis have not been investigated and clarified clearly. This study was designed to investigate the chemicals in P. chinense and explore its effect on liver fibrosis. First, we developed a highly efficient method, called DDA-assisted DIA, which can both broaden mass spectrometry (MS) coverage and MS² quality. In DDA-assisted DIA, data-dependent acquisition (DDA) and data-independent acquisition (DIA) were merged to construct a molecular network, in which 1,094 mass features were retained in Penthorum chinense Pursh (P. chinense). Out of these, 169 compounds were identified based on both MS¹ and MS² analysis. After that, based on a network pharmacology study, 94 bioactive compounds and 440 targets of P. chinense associated with liver fibrosis were obtained, forming a tight compound–target network. Meanwhile, the network pharmacology experimental results showed that multiple pathways interacted with the HIF-1 pathway, which was first identified involved in P. chinense. It could be observed that some proteins, such as TNF-α, Timp1, and HO-1, were involved in the HIF-1 pathway. Furthermore, the pharmacological effects of P. chinense on these proteins were verified by CCl₄-induced rat liver fibrosis, and P. chinense was found to improve liver functions through regulating TNF-α, Timp1, and HO-1 expressions. In summary, DDA-assisted DIA could provide more detailed compound information, which will help us to annotate the ingredients of TCM, and combination with computerized network pharmacology provided a theoretical basis for revealing the mechanism of P. chinense.

Nonselective Cell Necrosis Mediated by the Total Flavones of Penthorum Chinensis Pursh and Thonningianin-A in Human Hepatic and Hepatoma Cells

Penthorum chinensis Pursh (PCP), family Penthoraceae, has been used for hundreds of years in China. With the launch of PCP tablets, clinical applications focused on liver fibrosis and hepatocarcinoma. The purpose of this research was to explore the selectivity and toxicity of the active pharmacodynamic ingredients of PCP in vitro. The total flavones of PCP (TFPCE) and thonningianin-A (Th-A), a major flavone in TFPCE, were investigated on the cell death patterns in human hepatoma cells (HepG2) and human hepatic cells (LO2), followed by a concentration detection of LDH in the supernatants. Apoptosis and necrosis detection kits were used to validate the patterns of cell death caused by TFPCE and Th-A. Finally, the cytotoxicity of both TFPCE and Th-A were reproduced in the colorectal adenocarcinoma cells (NCI-H716). The results indicated that TFPCE inhibits the cell viability of HepG2 cells at a concentration lower than 25 μg/mL. Alternatively, the cell viability of LO2 cells dramatically decreased in the treatment of TFPCE at 25 μg/mL. The effects of Th-A on the cell viability of HepG2 cells and LO2 cells were consistent with TFPCE. LDH detection indicated that TFPCE and Th-A increased the LDH concentration of the supernatants in a dose-dependent way, indicating the pattern of cell necrosis. Fluorescence staining verified the necrosis cell death caused by TFPCE and Th-A. A dose-dependent tendency was obtained in NCI-H716 cells, indicating that the cell viability of NCI-H716 cells was significantly suppressed with the treatment of TFPCE and Th-A. Our results bring the potential toxicity of PCP to the forefront of public attention. Therefore, the clinical application of P chinensis is required to focus more on its cytotoxic effect.

Comparative Evaluation of the Potential Antitumor of Helleborus purpurascens in Skin and Breast Cancer

In the field of oncology, the plant kingdom has an inexhaustible supply of bioactive compounds. Phytochemical compounds isolated from Helleborus species have been found to be useful in various chronic diseases. This has brought Helleborus to the attention of medical researchers. H. purpurascens is a plant characteristic of the Carpathian area, known since ancient times for its beneficial effects. The aim of the study was to evaluate the flavonoids composition of a hydroalcoholic extract of H. purpurascens, as well as to assess its antioxidant activity and antitumor potential at the level of two healthy cell lines and four tumor cell lines. In addition, the expression of the genes involved in the apoptotic process (Bcl-2, Bad, and Bax) were evaluated. The results indicated that the extract has a high concentration of flavonoids, such as epicatechin, quercetin, and kaempferol. The extract has an increased antioxidant activity, very similar to that of the standard, ascorbic acid and cytotoxic effects predominantly in the breast cancer cell line, being free of cytotoxic effects in healthy cell lines. Underlying the cytotoxic effect is the induction of the process of apoptosis, which in the present study was highlighted by decreasing the expression of anti-apoptotic genes (Bcl-2) and increasing the expression of pro-apoptotic genes (Bad and Bax). In conclusion, the hydroalcoholic extract of H. purpurascens can be considered an important source for future medical applications in cancer therapy.

Identification of neolignans with PCSK9 downregulatory and LDLR upregulatory activities from Penthorum chinense and the potential in cholesterol uptake by transcriptional regulation of LDLR via SREBP2

ETHNOPHARMACOLOGICAL RELEVANCE

Penthorum chinense has been used in East Asia for the treatment of cholecystitis, infectious hepatitis, jaundice and to treat liver problems. Recent evidences provided the potential for the clinical use of P. chinense in the treatment of metabolic disease.

AIM OF THE STUDY

Based on the traditional use and recent evidences, we investigated the effects of constituents from P. chinense with modulation on proprotein convertase subtilisin/kexin type 9 (PCSK9) and low-density lipoprotein receptor (LDLR) expression, and the effect of the most active substance on cholesterol uptake, and genes relevant to lipid metabolism.

MATERIALS AND METHODS

The isolation of compounds from the BuOH-soluble extract of 80% methanol extract of P. chinense was conducted using chromatographic methods and the structures were established by interpreting spectroscopic data. Quantitative real time-PCR, and Western blot analysis were performed to monitor the regulatory activity on PCSK9 and LDLR expression. PCSK9-LDLR binding interaction was also tested. The cholesterol uptake in hepatocyte was measured using 1,1-dioctadecyl-3,3,3,3-tetramethylindocarbocyanine perchlorate (DiI)-labeled LDL cholesterol. Additionally, gene network analysis of LDLR and responses of its target proteins were carried out to discover genes germane to the effect of active compound on HepG2 cells. Moreover, we performed protein-protein interaction analysis via String and constructed the compound target network using Cytoscape.

RESULTS

Two new neolignans and 37 known compounds were characterized from P. chinense. Of the isolated compounds, (7'E,8S)-2',4,8-trihydroxy-3-methoxy-2,4'-epoxy-8,5'-neolign-7'-en-7-one (3), penthorin A (4) and methyl gallate (25) were found to suppress PCSK9 mRNA expression with IC₅₀ values of 5.13, 15.56 and 11.66 μM, respectively. However, all the isolated compounds were found to be inactive in PCSK9-LDLR interaction assay. Additionally, a dibenzoxepine-type lignan analog, (7'E,8S)-2',4,8-trihydroxy-3-methoxy-2,4'-epoxy-8,5'-neolign-7'-en-7-one (3) demonstrated to upregulate LDLR mRNA and protein expression via transcriptional factor sterol regulatory element-binding protein 2 (SREBP2). Furthermore, (7'E,8S)-2',4,8-trihydroxy-3-methoxy-2,4'-epoxy-8,5'-neolign-7'-en-7-one (3) increase the LDL-cholesterol uptake in DiI-LDL assay.

CONCLUSION

(7'E,8S)-2',4,8-trihydroxy-3-methoxy-2,4'-epoxy-8,5'-neolign-7'-en-7-one (3) seemed to increase potentially cholesterol uptake via the downregulation of PCSK9 and the activation of LDLR in hepatocytes. Moreover, SREBP2 was found to play an important role in regulation of PCSK9 and LDLR by (7'E,8S)-2',4,8-trihydroxy-3-methoxy-2,4'-epoxy-8,5'-neolign-7'-en-7-one.

A review of Penthorum chinense Pursh for hepatoprotection: Traditional use, phytochemistry, pharmacology, toxicology and clinical trials

ETHNOPHARMACOLOGICAL RELEVANCE

In China, Penthorum chinense Pursh (P. chinense) has been used for hundreds of years traditionally for alleviating symptoms by excessive intake of alcohol as well as in the treatment of traumatic injury, edema and liver diseases. Recently, P. chinense and its extract have been developed into tea, drinks or medicines for treatment of liver diseases, including hepatic virus infections, alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD) and liver fibrosis.

AIM OF THE STUDY

The main purpose of this review is to provide a critical appraisal of the existing knowledge on the phytochemical data, quality control aspect, pharmacological, as well as toxicological and clinical studies performed on P. chinense, including the identification of scientific gaps.

MATERIALS AND METHODS

A detailed literature search was conducted using various online search engines, such as Pubmed, Scopus, Google Scholar, Mendeley, Web of Science as well as China National Knowledge Infrastructure (CNKI) database.

RESULTS

In the pharmacological studies, there clearly are links between local/traditional uses and the biomedical investigations. Most pharmacological studies indicated potential liver protective effects in experimental models of chemicals-induced liver injury, acute and chronic alcoholic liver injury, NAFLD, liver fibrosis and viral infection, potentially through antioxidant effects, balancing key liver enzyme levels, inhibition of hepatic virus DNA replication, inhibition of hepatic stellate cells activation and inflammation either in vitro or in vivo. In some models, the effects of P. chinense is comparable with the one of silymarin. Clinical studies have suggested that P. chinense is safe and effective in treating several liver diseases, although most of them are not double-blinded and placebo-controlled studies. Toxicology studies show that P. chinense has no obvious toxicity or side effects in animals or human. Flavonoids, lignans, coumarins, polyphenols and organic acids have been identified. However, only a few studies have investigated the active compounds (mainly flavonoids and lignans) and molecular mechanisms of P. chinense.

CONCLUSION

P. chinense seems to be safe and shows relevant liver protecting effects. Therefore, it might be a promising candidate for developing as new hepatoprotective agents. However, a lack of understanding of the active compounds and mechanisms of action needs further attention.

Characterization of chemical composition and prebiotic effect of a dietary medicinal plant Penthorum chinense Pursh

Penthorum chinense Pursh is a dietary medicinal plant widely distributed in Asia-Pacific countries. The present study aims to profile the chemical constituents of P. chinense and investigate its prebiotic role in modulating gut microbiota. Fifty polyphenolic compounds were rapidly identified using UPLC-HR-MS. Total flavonoid and phenolic contents of P. chinense were 46.6% and 61.3% (w/w), respectively. Thirteen individual polyphenols were quantified, which accounted for 33.1% (w/w). P. chinense induced structural arrangement of microbial community in mice, showing increased microbiota diversity, elevated Bacteroidetes/Firmicutes ratio and enriched gut health-promoting bacteria. After a one-week drug-free wash, most of these changes were recovered, but the abundance of some beneficial bacteria was further increased. The altered composition of gut microbiota enriched several metabolic pathways. Moreover, P. chinense increased antioxidant capacity in vivo. The results suggest that polyphenol-enriched P. chinense modulates gut microbiota and enhances antioxidant capacity in mice toward a beneficial environment for host health.

Bioactivity Evaluation of Pinocembrin Derivatives From Penthorum chinense Pursh Stems

The extract of Penthorum chinense Pursh (PCP), a well-known Miao herb medicine, has been used as a key component for a Chinese patented drug to treat several kinds of liver-related diseases. In this work, 3 pinocembrin derivatives, S1, S2, and S3, were isolated from PCP stems and identified with high-performance liquid chromatography and electrospray ionization mass spectrometer. The molecular masses of S1, S2, and S3 were identical to Pinocembrin-7-O-[4″,6″-hexahydroxydiphenoyl (HHDP)]-β-D-glucose, Pinocembrin-7-O-[3″-O-galloyl-4″,6″-(s)-HHDP)-β-D-glucose, and Thonningianin A, respectively. Their free radical scavenging capability was evaluated with the 2,2-diphenyl-1-picrylhydrazyl assay. The half-maximal effective concentrations of S1, S2, and S3 were 26.75, 9.06, and 5.50 μg/mL, respectively. In vitro AML-12 assays demonstrated that S1 (5-20 μg/mL), S2 (10-40 μg/mL), and S3 (10-40 μg/mL) not only protected cells from H2O2-induced oxidation and alcohol-induced cell damages, but also reduced oleic acid (OA)-induced triglyceride accumulations in a dose-dependent manner. However, the 3 compounds potently exhibited similar cytotoxicity effect at high concentrations. The half-maximal inhibitory concentrations of S1, S2, and S3 to AML-12 cells were 74.19, 85.86, and 80.43 μg/mL. In addition, the 3 compounds also showed antibacterial activity on Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Lactobacillus rhamnosus, and Bacillus subtilis.

Three new flavonoids from Penthorum chinense Pursh and their docking studies

Three new flavonoids, pinocembrin-7-O-[3″-O-galloyl]-β-D-glucose (1), pinocembrin-7-O-[2″-O-galloyl-4″,6″-hexahydroxydiphenoyl]-β-D-glucose (2), 2',6'-dihydroxydihydrochalcone-4'-O-[2″-O-galloyl-4″,6″-hexahydroxydiphenoyl]-β-D-glucopyranoside (3), and 12 known compounds (4-15) were isolated from Penthorum Chinense Pursh. The structures of all compounds were established mainly by NMR and MS experiments as well as the necessary chemical evidence. The anti-hyperlipidemic activities of the three new flavonoids were predicted by molecular docking.

Ellagitannins and Related Compounds from Penthorum chinense

Four new ellagitannin metabolites, penthorumnins A-D (1-3 and 5), were isolated from the dried stem of Penthorum chinense. The structures were determined using spectroscopic and chemical analysis as well as using computations that revealed the following: (1) the acyl group of penthorumnin A (1) has a unique cyclopentane carboxylic acid structure that is derived from a hexahydroxydiphenoyl (HHDP) group; (2) penthorumnin B (2) has a 2-carboxymethyl-2,3-dihydro-3-oxo-1 H-indene-1-carboxylic acid structure that originates from the acyl group of penthorumnin A; (3) penthorumnin C (3) is a glucoside of trihydroxyacetophenone with an acyl group that is oxidatively derived from the HHDP group. This acyl group is closely related to that of balanophotannin F (4), which has been previously isolated from Balanophora japonica and whose absolute configuration has been revised using the DFT method; and (4) penthorumnin D (5) is defined as 2',4',6'-trihydroxyacetophenone 4'- O-[4,6-( S)-dehydrohexahydroxydiphenoyl]-β-glucoside. The variety of acyl groups in these ellagitannins is indicative of the occurrence of a unique metabolism in this plant involving the HHDP ester.

Enzymatic Extraction, Purification, and Characterization of Polysaccharides from Penthorum chinense Pursh: Natural Antioxidant and Anti-Inflammatory

Penthorum chinense Pursh (PCP) is a kind of functional food or medicine for liver protection. In the present work, Plackett-Burman design, steepest ascent method, and response surface methodology (RSM) were employed to obtain maximum total sugar yield. The experimental yield of 6.91% indicated a close agreement with the predicted yield of 7.00% of the model under optimized conditions. The major polysaccharide fraction (PCPP-1a) from PCPP was purified and identified as acidic polysaccharides with a high content of uronic acid (FT-IR, UV, HPGPC). PCPP had similar monosaccharide profile with PCPP-1a but was rich in galacturonic acid (HPLC). Both of PCPP and PCPP-1a possessed strong hydroxyl radical scavenging, DPPH radical scavenging, and Fe²⁺ chelating activities. Moreover, they were revealed to show strong anti-inflammatory activities by inhibiting NO, TNF-α, and IL-1β release compared to LPS treatment in RAW264.7 cells. These data suggest that the polysaccharides from PCP could be potential natural products for treating ROS and inflammatory-related diseases.

Quality assessment of Penthorum chinense Pursh through multicomponent qualification and fingerprint, chemometric, and antihepatocarcinoma analyses

An efficient method combined with fingerprint and chemometric analyses was developed to evaluate the quality of Penthorum chinense Pursh.

Traditional Chinese Herbal Medicine Penthorum chinense Pursh: A Phytochemical and Pharmacological Review

Penthorum chinense Pursh (ganhuangcao), a traditional Chinese medicine, is used for the prevention and treatment of liver diseases, including hepatitis B, hepatitis C, and alcoholic liver damage. A wide range of investigations have been carried out on this herbal medicine from pharmacognosy to pharmaceuticals, as well as pharmacology. The extract of P. chinense was reported to have significant liver protective effects through anti-oxidation, reduction of key enzyme levels, inhibition of hepatitis B virus DNA replication, and promotion of bile secretion. Based on the current knowledge, flavonoids and phenols are considered to be responsible for P. chinense's bioactivities. The main purpose of this review is to provide comprehensive and up-to-date knowledge of the phytochemical and pharmacological studies performed on P. chinense during the past few decades. Moreover, it intends to provide new insights into the research and development of this herbal medicine.

Evaluation of hypoglycemic effects of polyphenols and extracts from Penthorum chinense

ETHNOPHARMACOLOGICAL RELEVANCE

Penthorum chinense Pursh has a long history of use as a health food and folk medicine to alleviate "heat"-associated disorders, promote circulation and diuresis, and to treat liver problems, and to protect the spleen. In this study we provide experimental evidence for the clinical use of Penthorum chinense in the treatment of diabetes mellitus. The aim of the study was to investigate the hypoglycemic effects of extracts and active constituents from Penthorum chinense.

MATERIALS AND METHODS

High fat diet and STZ (35mg/kg) induced diabetic rats were administered with Penthorum chinense extract at graded oral doses (150 and 300mg/kg/day, ig.) for 2 weeks. A range of parameters, including blood glucose and lipid, serum insulin, glucose tolerance, were tested to evaluate its anti-hyperglycemic effects. Moreover, oral starch tolerance test (OSTT) was performed to test the level of postprandial glucose after administrating Penthorum chinense extract. In vitro study, the Penthorum chinense extracts and purified Penthorum chinense polyphenols were tested for α-amylase inhibitory activity. The polyphenols were determined by UPLC-Q-TOF mass spectrometry and NMR.

RESULTS

The Penthorum chinense extract possessed anti-hyperglycemic activities as shown by the decreased serum levels of glycosylated hemoglobulin A1C (HbA1c), triglyceride(TG), total cholesterol (TC), and low density lipoprotein-cholesterol (LDL-C), as well as increased serum levels of high density lipoprotein-cholesterol (HDL-C) and insulin. Penthorum chinense extract also improved the oral glucose tolerance test (OGTT) to a certain degree. Moreover, the OSTT study showed that in diabetic rats, the extract (600mg/kg) caused a significant hypoglycemic effect with a blood glucose reduction of 42% at 60min. To identify the active constituents, three polyphenols, pinocembrin-7-O-[4″,6″-hexahydroxydiphenoyl]-β-d-glucose (1), pinocembrin-7-O-[3″-O-galloyl-4″, 6″-hexahydroxydiphenoyl]-β- d-glucose (2), and thonningianin A (3) were isolated from Penthorum chinense. Compounds 1-3 moderately inhibited α-amylase activity, with IC50 values of 0.14, 0.03, and 0.08µmol/ml, respectively.

CONCLUSIONS

The folk medicinal plant, Penthorum chinense produced a moderated anti-hyperglycemic effect on STZ-induced diabetic rats and starch induced postprandial hyperglycemic mice.