Intestinal metabolite compound K of panaxoside inhibits the growth of gastric carcinoma by augmenting apoptosis via Bid-mediated mitochondrial pathway

Ginsenoside CK, rather than Rb1, possesses potential chemopreventive activities in human gastric cancer via regulating PI3K/AKT/NF-κB signal pathway

Ginsenoside Rb1, a main component of ginseng, is often transformed into ginsenoside CK by intestinal flora to exert various pharmacological activity. However, it remains unclear whether ginsenoside CK is responsible for the anti-gastric cancer effect of ginsenoside Rb1 in vivo. In this study, network pharmacology was applied to predict the key signal pathways of ginsenoside Rb1 and ginsenoside CK when treating gastric cancer. The anti-proliferative effects of ginsenoside Rb1 and ginsenoside CK and the underlying mechanism in gastric cancer cells were explored by MTT, Hoechst3328 staining, ELISA, RT-qPCR and Western blotting. The results showed that PI3K-AKT/NF-κB signal pathway was the common important pathway of ginsenoside Rb1 and CK in the treatment of gastric cancer. The results of MTT assay showed that ginsenoside Rb1 could hardly inhibit the proliferation of HGC-27 cells, whereas ginsenoside CK could inhibit the proliferation of HGC-27 cells. Hoechst3328 staining showed that cells in the ginsenoside CK group were densely stained bright blue and nuclear fragmented, indicating that apoptosis occurred. ELISA results showed that ginsenoside CK could effectively downregulate the levels of cyclin CyclinB1 and CyclinD1, but ginsenoside Rb1 had no significant effect. Also, the results of Western blot and RT-qPCR showed that ginsenoside CK inhibited the expressions of anti-apoptosis-related protein Bcl-2 and apoptosis-related pathway PI3K/AKT/NF-κB, and promoted the expression of pro-apoptosis proteins Bax and Caspase 3, whereas ginsenoside Rb1 exerted no effect. In short, ginsenoside Rb1 had no anti-gastric cancer cell activity in vitro, but ginsenoside CK could effectively inhibit cell proliferation and induce cell apoptosis in HGC-27 cells. The mechanism might relate to the inhibitory effect of ginsenoside CK on the PI3K/AKT/NF-κB pathway. These results suggest that ginsenoside CK might be the in vivo material basis for the anti-gastric cancer activity of ginsenosides.

Corilagin induces apoptosis and inhibits HMBG1/PI3K/AKT signaling pathways in a rat model of gastric carcinogenesis induced by methylnitronitrosoguanidine

Gastric cancer, invasive cancer of the gastrointestinal tract, found in developing countries. Chemotherapy to patients with advanced gastric cancer, exhibits greater drug resistance to standard chemotherapy drugs. Therefore, important to establish anti-cancer drugs that are successful for cancer therapy. Corilagin is a natural ellagitannin (ET) with profound pharmacological properties has been used for the study to assess its anticancer effects against N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) stimulated gastric cancer rats. Biochemical studies showed Thiobarbituric acid reactive substances (TBARS) and enzymatic and non-enzymatic antioxidants increased in corilagin treated animals compared with controls. Histopathologic evaluation revealed corilagin treated rats showed cell morphology similar that control showing its ameliorating effects. In corillagen treament mRNA protein expression levels of HIF-1α, AKT, PI3K, CT4, CD147 and HMGB1 were drastically lowered transcription factors triggering gastric cancer. In Western blot analysis showed released higher apoptotic marker of caspase-3, -9, Bax while Bcl-2 levels were significantly reduced confirming that corilagin triggers apoptosis in gastric cancer.

Functional Mechanism of Ginsenoside Compound K on Tumor Growth and Metastasis

Ginsenosides, as the most important constituents of ginseng, have been extensively investigated in cancer chemoprevention and therapeutics. Among the ginsenosides, Compound K (CK), a rare protopanaxadiol type of ginsenoside, has been most broadly used for cancer treatment due to its high anticancer bioactivity. However, the functional mechanism of CK in cancer is not well known. This review describes the structure, transformation and pharmacological activity of CK and discusses the functional mechanisms of CK and its metabolites, which regulate signaling pathways related to tumor growth and metastasis. CK inhibits tumor growth by inducing tumor apoptosis and tumor cell differentiation, regulates the tumor microenvironment by suppressing tumor angiogenesis-related proteins, and downregulates the roles of immunosuppressive cells, such as myeloid-derived suppressor cells (MDSCs). There is currently much research on the potential development of CK as a new strategy when administered alone or in combination with other compounds.

Ginsenoside M1 Induces Apoptosis and Inhibits the Migration of Human Oral Cancer Cells

Oral squamous cell carcinoma (OSCC) accounts for 5.8% of all malignancies in Taiwan, and the incidence of OSCC is on the rise. OSCC is also a common malignancy worldwide, and the five-year survival rate remains poor. Therefore, new and effective treatments are needed to control OSCC. In the present study, we prepared ginsenoside M1 (20-O-beta-d-glucopyranosyl-20(S)-protopanaxadiol), a major deglycosylated metabolite of ginsenoside, through the biotransformation of Panax notoginseng leaves by the fungus SP-LSL-002. We investigated the anti-OSCC activity and associated mechanisms of ginsenoside M1 in vitro and in vivo. We demonstrated that ginsenoside M1 dose-dependently inhibited the viability of human OSCC SAS and OEC-M1 cells. To gain further insight into the mode of action of ginsenoside M1, we demonstrated that ginsenoside M1 increased the expression levels of Bak, Bad, and p53 and induced apoptotic DNA breaks, G1 phase arrest, PI/Annexin V double-positive staining, and caspase-3/9 activation. In addition, we demonstrated that ginsenoside M1 dose-dependently inhibited the colony formation and migration ability of SAS and OEC-M1 cells and reduced the expression of metastasis-related protein vimentin. Furthermore, oral administration or subcutaneous injection of ginsenoside M1 significantly reduced tumor growth in SAS xenograft mice. These results indicate that ginsenoside M1 can be translated into a potential therapeutic against OSCC.

Review of ginsenosides targeting mitochondrial function to treat multiple disorders: Current status and perspectives

Mitochondrial dysfunction contributes to the pathogenesis and prognosis of many common disorders, including neurodegeneration, stroke, myocardial infarction, tumor, and metabolic diseases. Ginsenosides, the major bioactive constituents of Panax ginseng (P. ginseng), have been reported to play beneficial roles in the molecular pathophysiology of these diseases by targeting mitochondrial dysfunction. In this review, we first introduce the types of ginsenosides and basic mitochondrial functions. Then, recent findings are summarized on different ginsenosides targeting mitochondria and their key signaling pathways for the treatment of multiple diseases, including neurological disorders, cancer, heart disease, hyperglycemia, and inflammation are summarized. This review may explain the common targets of ginsenosides against multiple diseases and provide new insights into the underlying mechanisms, facilitating research on the clinical application of P. ginseng.

The effects of cytarabine combined with ginsenoside compound K synergistically induce DNA damage in acute myeloid leukemia cells

AML is a kind of hematological malignant tumor that urgently requires different treatment options in order to increase the cure rate and survival rate. Cytarabine (ara-C) is currently the main drug used to treat AML patients and is usually combined with different chemotherapeutic agents. However, due to resistance to ara-C, a new combination is needed to reduce ara-C resistance and improve treatment outcome. As is known to all, ginseng is a traditional Chinese herb; compound K is the principal metabolic product of ginsenoside which also has anti-cancer activity in some cancer cells, while the mechanism is unclear. In our previous study, we found that compound K inhibited AML cell viability and induced apoptosis, and compound K combined with ara-C synergistically induced AML cell proliferation arrest. Thus, we sought to investigate the reason for this by focusing on the mitochondrial dysfunction and DNA damage. In this paper, our results provide a foundation for the clinical evaluation of concomitant administration of compound K and ara-C in order to reduce the resistance to ara-C and improve AML treatment.

Suppressing PLCγ1 enhances osteogenic and chondrogenic potential of BMSCs

Phosphatidylcholine-specific phospholipase Cγ1 (PLCγ1) is involved in regulating cell metabolism. However, little is known how PLCγ1 directs BMSC differentiation. Here, we investigated the role of PLCγ1 in rat BMSC differentiation into osteoblasts and chondrocytes. The results of Alizarin red and Alcian blue staining showed that PLCγ1 inhibitor U73122 significantly enhanced the mineralization capacity and proteoglycan deposition of BMSCs. The results of qPCR technique and Western blot analysis showed that long-term treatment of U73122 enhanced COL1A1 and OPG mRNA levels and Collagen 1A1, BMP2, and p-Smad1/5/9 protein levels and that short-term treatment of U73122 enhanced COL2A1 and SOX9 mRNA levels and Collagen 2, SOX9, Aggrecan, TGF-β3, and p-Smad2/3 protein levels. Decreased p-mTOR and p-P38 contributed to enhanced osteogenic potentials of BMSCs and increased p-P38 contributed to enhanced chondrogenic potentials of BMSCs. The scaffold transplantation with U73122+BMSC was more efficacious than BMSC alone for osteochondral defect repair in a rat model. Therefore, suppressing PLCγ1 could improve the capacity to effectively use BMSCs for cell therapy of osteochondral defect.

Anti-Inflammatory Effects of Fermented Bark of Acanthopanax sessiliflorus and Its Isolated Compounds on Lipopolysaccharide-Treated RAW 264.7 Macrophage Cells

The fermentation was carried out on the bark of Acanthopanax sessiliflorus (AS). Acanthopanax species have been used in traditional medicine as tonics, sedatives, and antispasmodics. An activity-guided isolation of the fermented bark of A. sessiliflorus (FAS) yielded several phytochemicals: acanthoside D (1), acanthoside B (2), daucosterol (3), protocatechuic acid (4), chlorogenic acid methyl ester (5), ciwujiatone (6), syringaresinol (7), farnesol (8), 3,4-dicaffeoylquinic acid (9), and falcarindiol (10). HPLC analysis showed that content of lignan glycoside (1) was decreased and 4 and 7 were increased after fermentation. Anti-inflammatory activities on FAS showed the decrease of nitric oxide (NO) production, and inhibitory activities of iNOS and COX-2, proinflammatory cytokines (IL-6 and tumor necrosis factor-α), and collagenase. The aglycone, syringaresinol (7), which was increased through fermentation showed enhanced activity than 1. Thus, FAS may have the potential to treat inflammatory disorders, such as arthritis.

Fermented Wild Ginseng by Rhizopus oligosporus Improved l-Carnitine and Ginsenoside Contents

We conducted this study to investigate the beneficial effects of Rhizopus oligosporus fermentation of wild ginseng on ginsenosides, l-carnitine contents and its biological activity. The Rhizopus oligosporus fermentation of wild ginseng was carried out at 30 °C for between 1 and 14 days. Fourteen ginsenosides and l-carnitine were analyzed in the fermented wild ginseng by the ultra high pressure liquid chromatography–mass spectrometry (UPLC–MS) system. Our results showed that the total amount of ginsenosides in ginseng increased from 3274 to 5573 mg/kg after 14 days of fermentation. Among the 14 ginsenosides tested, the amounts of 13 ginsenosides (Rg1, Rb2, Rb3, Rc, Rd, Re, Rf, Rg2, Rg3, Rh1, compound K, F1 and F2) increased, whereas ginsenoside Rb1 decreased, during the fermentation. Furthermore, l-carnitine (630 mg/kg) was newly synthesized in fermented ginseng extract after 14 days. In addition, both total phenol contents and DPPH radical scavenging activities showed an increase in the fermented ginseng with respect to non-fermented ginseng. These results show that the fermentation process reduced the cytotoxicity of wild ginseng against RAW264.7 cells. Both wild and fermented wild ginseng showed anti-inflammatory activity via inhibition of nitric oxide synthesis in RAW264.7 murine macrophage cells.

Insights into gastrointestinal microbiota-generated ginsenoside metabolites and their bioactivities

The gastrointestinal microbiota and host co-evolve into a complex 'super-organism,' and this relationship plays a vital role in many physiological processes, such as drug metabolism. Ginseng is an important medicinal resource and the main ingredients are ginsenosides, which are less polar, difficult to absorb, and have low bioavailability. However, studies have shown that the biological activity of ginsenosides such as compound K (CK), ginsenoside Rg3 (Rg3), ginsenoside Rh2 (Rh2), 20(S)-protopanaxatriol (20(S)-PPT), and 20(S)-protopanaxadiol (20(S)-PPD) is closely related to the gastrointestinal microbiota. In this paper, the metabolic pathway of gastrointestinal microbiota-generated ginsenosides and the main pharmacological effects of these metabolites are discussed. Furthermore, our study provides a new insight into the discovery of novel drugs. Specifically, in new drug screening process, candidates with low biological activity and bioavailability should not be excluded. Because their metabolites may exhibit good pharmacological effects due to the involvement of the gastrointestinal microbiota. In addition, in further research studies to develop probiotics, a combination of agents could exert greater efficacy than single agents. Moreover, differences in lifestyle and diet lead to differences in the gastrointestinal microbiota in the human body. Therefore, administration of the same drug dose to different individuals could elicit different therapeutic effects, owing to the involvement of the gastrointestinal microbiota. Thus, treatment accuracy could be achieved by detecting the gastrointestinal microbiota before drug treatment.HighlightsGastrointestinal microbiota plays a decisive role in bioactivities of ginsenosides.The metabolic pathway and main pharmacological effects of ginsenoside metabolites are discussed.It provides new insights into novel drug discovery and further research to find probiotic, combinations to exert greater efficacy.Differences in lifestyle and diet, varies the gastrointestinal microbiota in the human body. However, the same dose of a drug producing different therapeutic effects may involve gastrointestinal microbiota.

7-H-Pyrrolo[2,3-d]pyrimidine derivative acts as promising agent for gastric cancer treatment by inducing cell death

In the present study effect of 7-H-pyrrolo[2,3-d]pyrimidine derivative (7-HPPD) on viability of MKN28 and MKN74 gastric cancer cells was investigated. There was no significant change in GES-1 cell viability on treatment with 7-HPPD for 48 h. MKN28 and MKN74 cell viability was reduced to 21 and 23%, respectively, on treatment with 7-HPPD at concentration of 50 µM. Hoechst 33342 staining showed that the cells treated with 7-HPPD showed condensation of chromatin material, presence of apoptotic bodies and intense blue fluorescence. Treatment of MKN28 and MKN74 cells with 7-HPPD markedly increased the release of LDH. Z-VAD-FMK prevented 7-HPPD-induced suppression of MKN28 and MKN74 cell viability. Exposure to 15, 20, 25, 30 and 50 µM concentrations of 7-HPPD caused concentration-based increase in caspase-8, -9, -3 and cleaved PARP. A significant increase in ROS production was caused by 7-HPPD in MKN28 and MKN74 cells. Increasing the concentration of 7-HPPD from 10 to 50 µM did not increase the expression of RIP3 protein. In summary, 7-HPPD suppresses gastric cancer cell growth by inducing apoptosis through increase in caspase expression and ROS production. Consequently, 7-HPPD may be used for the development of treatment strategy for gastric cancer.

Inhibition of Proliferation of SGC7901 and BGC823 Human Gastric Cancer Cells by Ursolic Acid Occurs Through a Caspase-Dependent Apoptotic Pathway

BACKGROUND Worldwide, gastric cancer is one of the most common malignant tumors. Ursolic acid is a plant metabolite and pentacyclic triterpenoid used in traditional Chinese medicine. This study aimed to investigate the effects of ursolic acid the growth and apoptosis of SGC7901 and BGC823 human gastric cancer cells in vitro. MATERIAL AND METHODS SGC7901 and BGC823 human gastric cancer cells and normal GES-1 gastric epithelial cells were cultured with increasing doses of ursolic acid at 50, 60, and 100 µM. Cell viability and proliferation were assessed using an MTT assay. Flow cytometry was used to assess cell apoptosis. Western blot was used to measure procaspase-8, procaspase-9, procaspase-3, and cleaved poly (ADP-ribose) polymerase (PARP) expression. The expression of receptor interaction protein 3 (RIP3) was examined by Western blot and reverse transcription polymerase chain reaction (RT-PCR). Morphological changes in the gastric cancer cells were determined using Hoechst 33342 staining following ursolic acid treatment. RESULTS Ursolic acid inhibited the viability of SGC7901 and BGC823 cells but not GES-1 cells. Ursolic acid treatment significantly induced apoptosis in SGC7901 and BGC823 cells when compared with GES-1 cells (P<0.05), and significantly increased the activation of caspase-3, caspase-8, caspase-9, poly ADPribose polymerase (PARP), and the production of reactive oxygen species (ROS). Treatment of SGC7901 and BGC823 cells with ursolic acid for 72 h did not induce necroptosis. CONCLUSIONS Ursolic acid inhibited the proliferation of SGC7901 and BGC823 human gastric cancer cells in vitro through a caspase-dependent apoptotic pathway.

Compound K attenuated hepatectomy-induced post-operative cognitive dysfunction in aged mice via LXRα activation

AIMS

Post-operative cognitive dysfunction (POCD) occurs after major surgery in elderly patients and affects the quality of patients' lives. The present study aims to explore the protective effects and possible mechanisms of compound K in old mice with POCD caused by partial hepatectomy.

METHODS

Sixteen month-old mice were administered different doses of compound K from the 8th day to 14th day after partial hepatectomy. Cognitive function was subsequently measured with a Morris water-maze (MWM) test. Serum inflammatory cytokine levels were measured by magnetic bead panel; levels of cytokines in the hippocampus were analyzed using immunohistochemistry and immunoblotting. The mRNA levels of target genes were measured using real-time PCR.

RESULTS

Compared with the model group, MWM scores were significantly attenuated at days 10 and 14 post-surgery in mice receiving compound K (10, 30 mg/kg) in a dose-dependent manner. Both systemic and local cytokine levels were reduced after treatment of compound K. The alterations in serum lipids were independent of the attenuation of POCD syndrome. An inhibitor of liver X receptor-α (LXRα), GGPP, reversed the effects of compound K.

CONCLUSIONS

The results provide evidence for an alleviation of POCD by compound K via local inflammation inhibition in hippocampus tissue; furthermore, the data suggests the mechanism involves the LXRα pathway. The present study supports further evaluation of compound K as a potential effective modulator for POCD.

High-density immobilization of a ginsenoside-transforming β-glucosidase for enhanced food-grade production of minor ginsenosides

Use of recombinant glycosidases is a promising approach for the production of minor ginsenosides, e.g., Compound K (CK) and F₁, which have potential applications in the food industry. However, application of these recombinant enzymes for food-grade preparation of minor ginsenosides are limited by the lack of suitable expression hosts and low productivity. In this study, Corynebacterium glutamicum ATCC13032, a GRAS strain that has been used extensively for the industrial-grade production of additives for foodstuffs, was employed to express a novel β-glucosidase (MT619) from Microbacterium testaceum ATCC 15829 with high ginsenoside-transforming activity. A cellulose-binding module was additionally fused to the N-terminus of MT619 for immobilization on cellulose, which is an abundant and safe material. Via one-step immobilization, the fusion protein in cell lysates was efficiently immobilized on regenerated amorphous cellulose at a high density (maximum 984 mg/g cellulose), increasing the enzyme concentration by 286-fold. The concentrated and immobilized enzyme showed strong conversion activities against protopanaxadiol- and protopanaxatriol-type ginsenosides for the production of CK and F₁. Using gram-scale ginseng extracts as substrates, the immobilized enzyme produced 7.59 g/L CK and 9.42 g/L F₁ in 24 h. To the best of our knowledge, these are the highest reported product concentrations of CK and F₁, and this is the first time that a recombinant enzyme has been immobilized on cellulose for the preparation of minor ginsenosides. This safe, convenient, and efficient production method could also be effectively exploited in the preparation of food-processing recombinant enzymes in the pharmaceutical, functional food, and cosmetics industries.

Ginsenoside compound K inhibits nuclear factor-kappa B by targeting Annexin A2

BACKGROUND

Ginsenoside compound K(C-K), a major metabolite of ginsenoside, exhibits anticancer activity in various cancer cells and animal models. A cell signaling study has shown that C-K inhibited nuclear factor-kappa B (NF-κB) pathway in human astroglial cells and liver cancer cells. However, the molecular targets of C-K and the initiating events were not elucidated.

METHODS

Interaction between C-K and Annexin A2 was determined by molecular docking and thermal shift assay. HepG2 cells were treated with C-K, followed by a luciferase reporter assay for NF-кB, immunofluorescence imaging for the subcellular localization of Annexin A2 and NF-кB p50 subunit, coimmunoprecipitation of Annexin A2 and NF-кB p50 subunit, and both cell viability assay and plate clone formation assay to determine the cell viability.

RESULTS

Both molecular docking and thermal shift assay positively confirmed the interaction between Annexin A2 and C-K. This interaction prevented the interaction between Annexin A2 and NF-кB p50 subunit and their nuclear colocalization, which attenuated the activation of NF-кB and the expression of its downstream genes, followed by the activation of caspase 9 and 3. In addition, the overexpression of Annexin A2-K320A, a C-K binding-deficient mutant of Annexin A2, rendered cells to resist C-K treatment, indicating that C-K exerts its cytotoxic activity mainly by targeting Annexin A2.

CONCLUSION

This study for the first time revealed a cellular target of C-K and the molecular mechanism for its anticancer activity.

Black Ginseng and Its Saponins: Preparation, Phytochemistry and Pharmacological Effects

Black ginseng is a type of processed ginseng that is prepared from white or red ginseng by steaming and drying several times. This process causes extensive changes in types and amounts of secondary metabolites. The chief secondary metabolites in ginseng are ginsenosides (dammarane-type triterpene saponins), which transform into less polar ginsenosides in black ginseng by steaming. In addition, apparent changes happen to other secondary metabolites such as the increase in the contents of phenolic compounds, reducing sugars and acidic polysaccharides in addition to the decrease in concentrations of free amino acids and total polysaccharides. Furthermore, the presence of some Maillard reaction products like maltol was also engaged. These obvious chemical changes were associated with a noticeable superiority for black ginseng over white and red ginseng in most of the comparative biological studies. This review article is an attempt to illustrate different methods of preparation of black ginseng, major chemical changes of saponins and other constituents after steaming as well as the reported biological activities of black ginseng, its major saponins and other metabolites.

Corilagin induces apoptosis, autophagy and ROS generation in gastric cancer cells in vitro

Corilagin, a unique component of the tannin family, has been identified in several medicinal plants. In previous literature, corilagin exhibited a marked anticancer property in a variety of human cancer cells. However, the biological effects of corilagin on gastric cancer and the mechanisms involved remain to be fully elucidated. In the present study, it was reported that corilagin induced inhibition of cell growth in SGC7901 and BGC823 cells in a concentration-dependent manner. It was found that corilagin exhibited less toxicity towards normal GES-1 cells. Furthermore, the study showed that corilagin induced the apoptosis of gastric cancer cells mainly via activating caspase-8, -9, -3 and poly ADP-ribose polymerase proteins. Simultaneously, it was verified that corilagin triggered autophagy in gastric cancer cells and the inhibition of autophagy improved the activity of corilagin on cell growth suppression. In addition, corilagin significantly increased intracellular reactive oxygen species production, which is important in inhibiting the growth of gastric cancer cells. Finally, it was shown that necroptosis cannot be induced by corilagin-incubation in SGC7901 and BGC823 cell lines. Consequently, these findings indicate that corilagin may be developed as a potential therapeutic drug for gastric cancer.

Corilagin inhibits breast cancer growth via reactive oxygen species-dependent apoptosis and autophagy

Corilagin is a component of Phyllanthus urinaria extract and has been found of possessing anti‐inflammatory, anti‐oxidative, and anti‐tumour properties in clinic treatments. However, the underlying mechanisms in anti‐cancer particularly of its induction of cell death in human breast cancer remain undefined. Our research found that corilagin‐induced apoptotic and autophagic cell death depending on reactive oxygen species (ROS) in human breast cancer cell, and it occurred in human breast cancer cell (MCF‐7) only comparing with normal cells. The expression of procaspase‐8, procaspase‐3, PARP, Bcl‐2 and procaspase‐9 was down‐regulated while caspase‐8, cleaved PARP, caspase‐9 and Bax were up‐regulated after corilagin treatment, indicating apoptosis mediated by extrinsic and mitochondrial pathways occurred in MCF‐7 cell. Meanwhile, autophagy mediated by suppressing Akt/mTOR/p70S6K pathway was detected with an increase in autophagic vacuoles and LC3‐II conversion. More significantly, inhibition of autophagy by chloroquine diphosphate salt (CQ) remarkably enhanced apoptosis, while the caspase inhibitor z‐VAD‐fmk failed in affecting autophagy, suggesting that corilagin‐induced autophagy functioned as a survival mechanism in MCF‐7 cells. In addition, corilagin induced intracellular reactive oxygen species (ROS) generation, when reduced by ROS scavenger NAC, apoptosis and autophagy were both down‐regulated. Nevertheless, in SK‐BR3 cell which expressed RIP3, necroptosis inhibitor Nec‐1 could not alleviate cell death induced by corilagin, indicating necroptosis was not triggered. Subcutaneous tumour growth in nude mice was attenuated by corilagin, consisting with the results in vitro. These results imply that corilagin inhibits cancer cell proliferation through inducing apoptosis and autophagy which regulated by ROS release.

An L213A variant of β-glycosidase from Sulfolobus solfataricus with increased α-L-arabinofuranosidase activity converts ginsenoside Rc to compound K

Compound K (C-K) is a crucial pharmaceutical and cosmetic component because of disease prevention and skin anti-aging effects. For industrial application of this active compound, the protopanaxadiol (PPD)-type ginsenosides should be transformed to C-K. β-Glycosidase from Sulfolobus solfataricus has been reported as an efficient C-K-producing enzyme, using glycosylated PPD-type ginsenosides as substrates. β-Glycosidase from S. solfataricus can hydrolyze β-d-glucopyranoside in ginsenosides Rc, C-Mc₁, and C-Mc, but not α-l-arabinofuranoside in these ginsenosides. To determine candidate residues involved in α-l-arabinofuranosidase activity, compound Mc (C-Mc) was docking to β-glycosidase from S. solfataricus in homology model and sequence was aligned with β-glycosidase from Pyrococcus furiosus that has α-l-arabinofuranosidase activity. A L213A variant β-glycosidase with increased α-l-arabinofuranosidase activity was selected by substitution of other amino acids for candidate residues. The increased α-l-arabinofuranosidase activity of the L213A variant was confirmed through the determination of substrate specificity, change in binding energy, transformation pathway, and C-K production from ginsenosides Rc and C-Mc. The L213A variant β-glycosidase catalyzed the conversion of Rc to Rd by hydrolyzing α-l-arabinofuranoside linked to Rc, whereas the wild-type β-glycosidase did not. The variant enzyme converted ginsenosides Rc and C-Mc into C-K with molar conversions of 97%, which were 1.5- and 2-fold higher, respectively, than those of the wild-type enzyme. Therefore, protein engineering is a useful tool for enhancing the hydrolytic activity on specific glycoside linked to ginsenosides.

Synthesis and Biological Evaluation of Ginsenoside Compound K Derivatives as a Novel Class of LXRα Activator

Compound K is one of the active metabolites of Panaxnotoginseng saponins, which could attenuate the formation of atherosclerosis in mice modelsvia activating LXRα. We synthesized and evaluated a series of ginsenoside compound K derivatives modified with short chain fatty acids. All of the structures of this class of ginsenoside compound K derivative exhibited comparable or better biological activity than ginsenoside compound K. Especially structure 1 exhibited the best potency (cholesteryl ester content: 41.51%; expression of ABCA1 mRNA: 319%) and low cytotoxicity.

Mesenchymal stem cells in inflammatory microenvironment potently promote metastatic growth of cholangiocarcinoma via activating Akt/NF-κB signaling by paracrine CCL5

Our previous work has demonstrated that mesenchymal stem cells (MSCs) could induce metastatic growth of the inflammation-related cholangiocarcinoma (CCA). However, the functional mechanism of MSCs on CCA progression in the early inflammatory microenvironment remained undetermined. Here, we showed that TNF-α and IFN-γ-induced inflammatory microenvironment stimulated the expression of TNF-α, CCL5, IL-6, IDO, and activated the NF-κB signaling with p65 nuclear translocation in MSCs cells. CCA cell lines QBC939 and Mz-chA-1 exposed to the conditioned medium of MSCs after being stimulated by TNF-α and IFN-γ (TI-CM) exhibited enhanced mobility. Moreover, MSCs pre-stimulated by both inflammatory cytokines (TI-MSCs) increased tumor metastasis in vivo. The conditioned medium of TI-MSCs stimulated the transcription of snail, slug, ZEB1 and ZEB2. Next, the expression of CCL5 of TI-MSCs was verified by ELISA, which indicated that MSCs contributed to CCA migration and metastasis in a paracrine fashion. CCA cells treated with TI-CM up-regulated CCA chemokine receptors, especially CCR5; CCL5 neutralizing antibody or CCR5 inhibitor Maraviroc inhibited the effects of MSCs on CCA cells migration. We also found that Akt/NF-κB signaling was activated by CCL5/CCR5 axis, which increased the expression of MMP2, MMP9. Together, these findings suggest that MSCs in tumor inflammatory microenvironment are elicited of CCL5, which activate AKT/NF-κB signaling and lead to metastatic growth of CCA cells.

General and Genetic Toxicology of Enzyme-Treated Ginseng Extract: Toxicology of Ginseng Rh2

OBJECTIVES

Ginseng Rh2+ is enzyme-treated ginseng extract containing high amounts of converted ginsenosides, such as compound k, Rh2, Rg3, which have potent anticancer activity. We conducted general and genetic toxicity tests to evaluate the safety of ginseng Rh2+.

METHODS

An acute oral toxicity test was performed at a high-level dose of 4,000 mg/kg/day in Sprague-Dawley (SD) rats. A 14-day range-finding study was also conducted to set dose levels for the 90-day study. A subchronic 90-day toxicity study was performed at dose levels of 1,000 and 2,000 mg/kg/day to investigate the no-observed-adverse-effect level (NOAEL) of ginseng Rh2+ and target organs. To identify the mutagenic potential of ginseng Rh2+, we conducted a bacterial reverse mutation test (Ames test) using amino-acid-requiring strains of Salmonella typhimurium and Escherichia coli (E. coli), a chromosome aberration test with Chinese hamster lung (CHL) cells, and an in vivo micronucleus test using ICR mice bone marrow as recommended by the Korean Ministry of Food and Drug Safety.

RESULTS

According to the results of the acute oral toxicity study, the approximate lethal dose (ALD) of ginseng Rh2+ was estimated to be higher than 4,000 mg/kg. For the 90-day study, no toxicological effect of ginseng Rh2+ was observed in body-weight changes, food consumption, clinical signs, organ weights, histopathology, ophthalmology, and clinical pathology. The NOAEL of ginseng Rh2+ was established to be 2,000 mg/kg/day, and no target organ was found in this test. In addition, no evidence of mutagenicity was found either on the in vitro genotoxicity tests, including the Ames test and the chromosome aberration test, or on the in vivo in mice bone marrow micronucleus test.

CONCLUSION

On the basis of our findings, ginseng Rh2+ is a non-toxic material with no genotoxicity. We expect that ginseng Rh2+ may be used as a novel adjuvant anticancer agent that is safe for long-term administration.

Compound K Attenuates the Development of Atherosclerosis in ApoE(-/-) Mice via LXRα Activation

Background: Atherosclerosis is a fundamental pathological process responded to some serious cardiovascular events. Although the cholesterol-lowering drugs are widely prescribed for atherosclerosis therapy, it is still the leading cause of death in the developed world. Here we measured the effects of compound K in atherosclerosis formation and investigated the probably mechanisms of the anti-antherosclerosis roles of compound K. Methods: We treated the atherosclerotic model animals (apoE^−/− mice on western diet) with compound K and measured the size of atherosclerotic lesions, inflammatory cytokine levels and serum lipid profile. Peritoneal macrophages were collected in vitro for the foam cell and inflammasome experiments. Results: Our results show that treatment with compound K dose-dependently attenuates the formation of atherosclerotic plaques by 55% through activation of reverse cholesterol transport pathway, reduction of systemic inflammatory cytokines and inhibition of local inflammasome activity. Compound K increases the cholesterol efflux of macrophage-derived foam cells, and reduces the inflammasome activity in cholesterol crystal stimulated macrophages. The activation of LXRα may contribute to the athero-protective effects of compound K. Conclusion: These observations provide evidence for an athero-protective effect of compound K via LXRα activation, and support its further evaluation as a potential effective modulator for the prevention and treatment of atherosclerosis.

TPGS-modified liposomes for the delivery of ginsenoside compound K against non-small cell lung cancer: formulation design and its evaluation in vitro and in vivo

Objective

This work aimed at preparing ginsenoside compound K (GCK)-loaded liposomes modified with TPGS (GCKT-liposomes) to enhance solubility and targeting capability of GCK, as well as inhibit the efflux of GCK from tumour cells.

Methods

GCKT-liposomes were prepared by the thin-film hydration method and characterized by particle size, polydispersity, zeta potential and drug encapsulation efficiency. A549 cells were used as antitumour cell model to access the cellular uptake of the GCK and perform its antitumour function. The enhancement of in vivo antitumour efficacy of GCKT-liposomes was evaluated by nude mice bearing tumour model.

Key findings

The results showed that GCKT-liposomes achieved a comparatively high drug loading efficiency and reasonable particle size at the ratio of 7 : 3 (phospholipid: TPGS). The in vitro release demonstrated that the dissolution of GCK was remarkably improved by entrapping it into liposomes. In addition, GCKT-liposomes exhibited a great hypersensitizing effect on A549 cells, and the cellular uptake was enhanced. Compared with free GCK, the IC50 of GCKT-liposomes was significantly reduced (16.3 ± 0.8 vs 24.9 ± 1.0 μg/ml). In vivo antitumour assay also indicated that GCKT-liposomes achieved higher antitumour efficacy (67.5 ± 0.5 vs 40.8 ± 0.7%).

Conclusion

The novel GCKT-liposomes significantly improved the antitumour efficacy of GCK.

Anticancer Activities of Protopanaxadiol- and Protopanaxatriol-Type Ginsenosides and Their Metabolites

Recently, most anticancer drugs are derived from natural resources such as marine, microbial, and botanical sources, but the low success rates of chemotherapies and the development of multidrug resistance emphasize the importance of discovering new compounds that are both safe and effective against cancer. Ginseng types, including Asian ginseng, American ginseng, and notoginseng, have been used traditionally to treat various diseases, due to their immunomodulatory, neuroprotective, antioxidative, and antitumor activities. Accumulating reports have shown that ginsenosides, the major active component of ginseng, were helpful for tumor treatment. 20(S)-Protopanaxadiol (PDS) and 20(S)-protopanaxatriol saponins (PTS) are two characteristic types of triterpenoid saponins in ginsenosides. PTS holds capacity to interfere with crucial metabolism, while PDS could affect cell cycle distribution and prodeath signaling. This review aims at providing an overview of PTS and PDS, as well as their metabolites, regarding their different anticancer effects with the proposal that these compounds might be potent additions to the current chemotherapeutic strategy against cancer.

Antimelanogenesis Activity of Hydrolyzed Ginseng Extract (GINST) via Inhibition of JNK Mitogen-activated Protein Kinase in B16F10 Cells

GINST is a hydrolyzed ginseng extract produced by an in vitro process that imitates the metabolic function of bacteria in the human digestive track and has approved by the Ministry of Food and Drug Safety of Korea for the management of postprandial hyperglycemia. Additionally, GINST has been reported to have other physiological functions including anti-aging and antioxidant effects. The objectives of this study are to compare the antimelanogenic effects of fresh ginseng extract (FGE) and GINST extract and to elucidate the functional mechanism. The concentration of total ginsenosides in FGE and GINST was measured using ultraperformance liquid chromatography with a C18 column. B16F10 cells were treated with FGE and GINST for 72 h to assess melanin content, tyrosinase activity, and protein levels of microphthalmia-associated transcription factor (MITF) and tyrosinase-related protein-1 (TRP-1). The activity of kinases involved in mitogen-activated protein kinase (MAPK) signaling, such as extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinases (JNK), and p38 mitogen-activated protein kinases (p38), were measured using western blots. While neither FGE nor GINST inhibited the activity of mushroom tyrosinase directly, GINST decreased melanogenesis and tyrosinase activity markedly. Furthermore, our results indicate that GINST downregulated the levels of MITF and TRP-1 possibly by suppressing JNK signaling. We concluded that, when compared to FGE, GINST has a superior antimelanogenic effect mediated by the downregulation of MITF, TRP-1, and intracellular tyrosinase activity via the JNK signaling pathway. Thus, we suggest that GINST has the potential to be used as a novel skin whitening agent.

Biotransformation of major ginsenosides in ginsenoside model culture by lactic acid bacteria

Background

Some differences have been reported in the biotransformation of ginsenosides, probably due to the types of materials used such as ginseng, enzymes, and microorganisms. Moreover, most microorganisms used for transforming ginsenosides do not meet food-grade standards. We investigated the statistical conversion rate of major ginsenosides in ginsenosides model culture during fermentation by lactic acid bacteria (LAB) to estimate possible pathways.

Methods

Ginsenosides standard mix was used as a model culture to facilitate clear identification of the metabolic changes. Changes in eight ginsenosides (Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, and Rg2) during fermentation with six strains of LAB were investigated.

Results

In most cases, the residual ginsenoside level decreased by 5.9–36.8% compared with the initial ginsenoside level. Ginsenosides Rb1, Rb2, Rc, and Re continuously decreased during fermentation. By contrast, Rd was maintained or slightly increased after 1 d of fermentation. Rg1 and Rg2 reached their lowest values after 1–2 d of fermentation, and then began to increase gradually. The conversion of Rd, Rg1, and Rg2 into smaller deglycosylated forms was more rapid than that of Rd from Rb1, Rb2, and Rc, as well as that of Rg1 and Rg2 from Re during the first 2 d of fermentation with LAB.

Conclusion

Ginsenosides Rb1, Rb2, Rc, and Re continuously decreased, whereas ginsenosides Rd, Rg1, and Rg2 increased after 1–2 d of fermentation. This study may provide new insights into the metabolism of ginsenosides and can clarify the metabolic changes in ginsenosides biotransformed by LAB.

Lentivirus-mediated shRNA targeting Nanog inhibits cell proliferation and attenuates cancer stem cell activities in breast cancer

Emerging evidences suggest that cancer stem cells (CSCs) are responsible for tumor growth, metastasis and treatment resistance. Nanog is one of the transcription factors that are essential for stem cellular physiology process. Previous studies reported that Nanog was detected in breast cancer and other solid tumors and indicated that it has oncogenic characteristics. However, expression feature of Nanog in breast cancer stem cells (BCSCs) enriched population and its biological function in BCSCs is poorly understood. In this study, CD44 + CD24- fraction sorting with Fluorescence Activated Cell Sorter and mammosphere culture were used for enriching BCSCs. We report here that Nanog was highly expressed in CSCs-enriched population from the breast cancer cells, as well as stemness-associated genes. In addition, we employed the lentivirus-mediated shRNA targeting Nanog to investigate function of Nanog in BCSCs. We found that targeted inhibition of Nanog could suppress proliferation and colony formation in breast cancer cells. Further studies showed that targeted inhibition of Nanog resulted in a decrease of BCSCs activities, including mammosphere formation, CD44 + CD24- proportion and expressions of stemness-associated genes. These data therefore suggest that Nanog possesses important function in BCSCs and targeted inhibition of Nanog may provide a novel means of targeting and eliminating BCSCs.

Ginsenoside metabolite compound K enhances the efficacy of cisplatin in lung cancer cells

OBJECTIVE

To evaluate the potential of ginsenoside metabolite compound K (CK) in enhancing the anti-tumor effects of cisplatin against lung cancer cells, including cell proliferation and apoptosis, and the underlying mechanism.

METHODS

Western blotting and p53 reporter assay were used to assess p53 expression and activity. MTT assay and TUNEL staining were employed to investigate the drug effects on cell growth and apoptosis, respectively. Combination index (CI) was calculated to determine synergism.

RESULTS

We found that CK could significantly enhance cisplatin-induced p53 expression and activity in two lung cancer cell lines, H460 and A549. Consequently, synergistic inhibition of cell growth was observed when the cells were co-treated with CK and cisplatin compared to single treatment. In addition, the ability of cisplatin in apoptosis induction was similarly synergized by CK. Furthermore, by using p53-null lung cancer cells, we demonstrate that the synergy was p53 dependent.

CONCLUSIONS

Conventional chemotherapies are often accompanied by development of drug resistance and severe side effects. Novel discoveries of low toxicity compounds to improve the outcome or enhance the efficacy of chemotherapies are of great interest. In the present study, our data provide the first evidence that CK could be potentially used as an agent to synergize the efficacy of cisplatin in lung cancer.

Ginseng polysaccharide injection induces apoptosis of gastric carcinoma SGC-7901 cells

AIM: To investigate the apoptosis-inducing effect of ginseng polysaccharide injection in gastric carcinoma SGC-7901 cells and the possible mechanism involved.

METHODS: SGC-7901 cells were treated with different concentrations (0, 12.5, 25.0, 50.0, 100.0 μL/mL) of ginseng polysaccharide injection for different durations (24, 48 or 72 h). Cell apoptosis was assessed by flow cytometry, and protein expression of Bax and Bcl-2 was determined by Western blot.

RESULTS: Ginseng polysaccharide injection significantly induced the apoptosis of SGC-7901 cells in vitro in a dose- and time-dependent manner. Treatment with ginseng polysaccharide injection significantly increased Bax protein expression and Bax/Bcl-2 ratio, and reduced Bcl-2 protein expression in a dose- and time-dependent manner.

CONCLUSION: Ginseng polysaccharide injection is able to induce apoptosis of gastric carcinoma SGC-7901 cells possibly by regulating Bax and Bcl-2 protein expression.

Compound K-induced apoptosis of human hepatocellular carcinoma MHCC97-H cells in vitro

An intestinal bacterial metabolite of ginseng protopanaxadiol saponin, 20-O-(β-D-glucopyranosyl)-20(S)-protopanaxadiol (compound K), has been reported to induce apoptosis in a variety of cancer cells. However, the precise mechanisms induced by compound K in human hepatocellular carcinoma (HCC) cells remain unclear. In order to examine possible apoptotic mechanisms, we investigated the anticancer effect of compound K in MHCC97-H. MTT assay showed that compound K inhibited the proliferation of MHCC97-H cells with a relatively low toxicity in normal hepatoma cells. Cell cycle progression and cell staining showed an increase in apoptotic sub-G1 fraction. Treatment of MHCC97-H with compound K also induced a reduction in mitochondrial membrane potential (Δψm) and DNA damage. Further study showed that compound K upregulated Fas, FasL, Bax/Bcl-2 ratio and downregulated pro-caspase-9, pro-caspase-3 in a dose-dependent manner, and it also inhibited Akt phosphorylation. These results suggest that compound K significantly inhibits cell proliferation and induces apoptosis in MHCC97-H cells through Fas- and mitochondria-mediated caspase-dependent pathways in human HCC cells.

Ginsenoside compound K induces apoptosis in nasopharyngeal carcinoma cells via activation of apoptosis-inducing factor

Background

Nasopharyngeal carcinoma (NPC) has a high incidence rate in Southern China. Although there are conventional therapies, the side effects and toxicities are not always tolerable for patients. Recently, the tumoricidal effect of ginsenosides on different cancer cells has been studied. This study aims to investigate the anti-cancer effect of ginsenosides on NPC cells and their underlying mechanism.

Methods

The cytotoxicity of ginsenosides on NPC cell line HK-1 was measured by MTT assay. Apoptosis was detected by propidium iodide staining followed by flow cytometry. A xenograft tumor model was established by injecting nude mice with HK-1 cells. The activation of caspases and apoptosis-inducing factor (AIF) were evaluated by Western blot analysis. Nuclear translocation of AIF was also studied by immunofluorescence staining. Mitochondrial membrane potential was measured by JC-1 dye using flow cytometry.

Results

Four ginsenosides, 20 (S)-Rh₂, compound K (CK), panaxadiol (PD) and protopanaxadiol (PPD), induced apoptotic cell death in HK-1 cells in a concentration-dependent manner. CK inhibited HK-1 xenograft tumor growth most extensively and depleted mitochondrial membrane potential depolarization and induced translocation of AIF from cytoplasm to nucleus in HK-1 cells. In addition, depletion of AIF by siRNA abolished CK-induced HK-1 cell death.

Conclusion

Ginsenoside CK-induced apoptosis of HK-1 cells was mediated by the mitochondrial pathway and could significantly inhibit tumor growth in vivo.

Transformation of ginsenosides from notoginseng by artificial gastric juice can increase cytotoxicity toward cancer cells

Multicomponent metabolic profile of notoginseng saponins in artificial gastric juice was qualitatively and quantitatively investigated, showing that ginsenosides were transformed via multiple pathways including deglycosylation, dehydration, hydration, and oxygenation. A total of 83 metabolites was identified by using UPLC-Q-TOF-MS, among which 16 new dammarane glycosides were further characterized by comparing with synthesized authentic compounds. Transformation time-course of notoginseng saponins in artificial gastric juice was quantitatively measured for the first time, showing rapid degradation of primary ginsenosides and concomitant formation of deglycosylation, hydration, and dehydration products. It was further demonstrated that the resultant metabolites exhibited enhanced cytotoxicity toward cancer cells. The extensive metabolism of ginsenosides within a transit time span in stomach, together with the formation of metabolites with diversified chemical structures possessing enhanced biological activities, indicated an important role of transformation in gastric juice in the systematic effects of ginsenosides.

Ginsenoside F(2) induces apoptosis in humor gastric carcinoma cells through reactive oxygen species-mitochondria pathway and modulation of ASK-1/JNK signaling cascade in vitro and in vivo

Ginsenoside F(2) (F(2)) is a potential bioactive metabolite of major ginsenosides. The potential anti-cancer effect of F(2) in gastric cancer cells has not been appraised. This study investigated the effects of F(2) on the production of reactive oxygen species (ROS). We also investigated the in vitro and in vivo effects of F(2) on the downstream signaling pathways leading to apoptosis in human gastric cancer cells. The in vitro data revealed that F(2) induces ROS accumulation followed by a decrease in mitochondrial transmembrane potential (MTP), and the release of cytochrome c (cyto c), which induced the caspase-dependent apoptosis. Further assay indicated that modulation of ASK-1/JNK pathway contributes to apoptosis. In vivo, F(2) exhibits the obvious anti-cancer effect compared with cisplatin with no obvious toxicity. Jointly, these results suggest that F(2) induces apoptosis by causing an accumulation of ROS and activating the ASK-1/JNK signaling pathway. This provides further support for the use of F(2) as a novel anticancer therapeutic candidate.

Ginsenoside metabolite compound K promotes recovery of dextran sulfate sodium-induced colitis and inhibits inflammatory responses by suppressing NF-κB activation

Phytogenic compounds with anti-oxidant and anti-inflammatory properties, such as ginsenoside metabolite compound K (CK) or berberine (BBR), are currently discussed as promising complementary agents in the prevention and treatment of cancer and inflammation. The latest study showed that ginsenoside Rb1 and its metabolites could inhibit TNBS-induced colitis injury. However, the functional mechanisms of anti-inflammation effects of ginsenoside, particularly its metabolite CK are still not clear. Here, using dextran sulfate sodium (DSS)-induced colitis in mice, clinical parameters, intestinal integrity, pro-inflammatory cytokines production, and signaling pathways in colonic tissues were determined. In mild and sever colitis mice, CK and BBR (as a positive agent) alleviated colitis histopathology injury, ameliorated myeloperoxidase (MPO) activity, reduced pro-inflammatory cytokines production, such as, IL-6, IL-1β, TNF-α, and increased anti-inflammatory cytokine IL-10 production in both mice colon tissues and blood. Nevertheless, the results revealed that CK and BBR inhibited NF-κB p65 nuclear translocation, downregulated p-IκBα and upregulated IκBα, indicating that CK, as well as BBR, suppressed the activation of the NF-κB pathway in the progression of colitis with immunofluorescence, immunohistochemical and western blotting analysis. Furthermore, CK inhibited pro-inflammatory cytokines production in LPS-activated macrophages via down-regulation of NF-κB signaling pathway. Taken together, our results not only reveal that CK promotes the recovery of the progression of colitis and inhibits the inflammatory responses by suppressing NF-κB activation, but also suggest that CK downregulates intestinal inflammation through regulating the activation of macrophages and pro-inflammatory cytokines production.

pH-responsive cancer-targeted selenium nanoparticles: a transformable drug carrier with enhanced theranostic effects

A cancer-targeted and structure-transformable drug delivery system has been constructed, which displays enhanced anticancer efficacy and exhibits the characteristics of shape transformation and pH-controlled drug release under acidifying cell organelles.

Cytoprotective effect of American ginseng in a rat ethanol gastric ulcer model

Panax quinquefolium L. (American Ginseng, AG) is one of the most popular herbal medicines in the World. We aimed to investigate whether chronic (28-day) supplementation with AG could protect against ethanol-induced ulcer in gastric tissue. Furthermore, we investigated the possible molecular mechanisms leading to AG-mediated gastric mucosal protection. We randomized 32 male Wistar rats into four groups for treatment (n = 8 per group): supplementation with water (vehicle) and low-dose (AG-1X), medium-dose (AG-2X) and high-dose (AG-5X) AG at 0, 250, 500, and 1250 mg/kg, respectively. In the first experiment, animals were fed vehicle or AG treatments for 4 weeks. At day 29, 75% ethanol was given orally to each animal at 10 mL/kg to induce gastric ulceration for 2 h. In a second experiment, animals were pretreated orally with each treatment for 1 hr before a single oral administration of ethanol (70%, 10 mL/kg). Trend analysis revealed that AG treatments inhibited ethanol-induced gastric mucosal damage. AG supplementation dose-dependently decreased the pro-inflammatory levels of interleukin 1β and cyclooxygenase 2 and the expression of pro-apoptotic proteins tBid, cytochrome C, and caspases-9 and -3 and increased the levels of anti-apoptotic proteins Bcl-2, Bcl-xL and p-Bad. AG could have pharmacological potential for treating gastric ulcer.

Biochemical basis of cancer chemoprevention and/or chemotherapy with ginsenosides (Review)

Cancer still imposes a global threat to public health. After decades of research on cancer biology and enormous efforts in developing anticancer therapies, we now understand that the majority of cancers can be prevented. Bioactive phytochemicals present in edible plants have been shown to reduce the risk of various types of cancer. Ginseng (Panax ginseng C.A. Meyer), which contains a wide variety of saponins, known as ginsenosides, is an age-old remedy for human ailments, including cancer. Numerous laboratory-based studies have revealed the anticancer properties of ginsenosides, which compel tumor cells to commit suicide, arrest the proliferation of cancer cells in culture and inhibit experimentally-induced tumor formation in laboratory animals. Ginsenosides have been reported to inhibit tumor angiogenesis, as well as the invasion and metastasis of various types of cancer cells. Moreover, ginsenosides as combination therapy enhance the sensitivity of chemoresistant tumors to clinically used chemotherapeutic agents. This review sheds light on the molecular mechanisms underlying the cancer chemopreventive and/or chemotherapeutic activity of ginsenosides and their intestinal metabolites with particular focus on the modulation of cell signaling pathways associated with oxidative stress, inflammation, cell proliferation, apoptosis, angiogenesis and the metastasis of cancer cells.

Ginseng saponin metabolite 20(S)-protopanaxadiol inhibits tumor growth by targeting multiple cancer signaling pathways

Plant-derived active constituents and their semi-synthetic or synthetic analogs have served as major sources of anticancer drugs. 20(S)-protopanaxadiol (PPD) is a metabolite of ginseng saponin of both American ginseng (Panax quinquefolius L.) and Asian ginseng (Panax ginseng C.A. Meyer). We previously demonstrated that ginsenoside Rg3, a glucoside precursor of PPD, exhibits anti-proliferative effects on HCT116 cells and reduces tumor size in a xenograft model. Our subsequent study indicated that PPD has more potent antitumor activity than that of Rg3 in vitro although the mechanism underlying the anticancer activity of PPD remains to be defined. Here, we investigated the mechanism underlying the anticancer activity of PPD in human cancer cells in vitro and in vivo. PPD was shown to inhibit growth and induce cell cycle arrest in HCT116 cells. The in vivo studies indicate that PPD inhibits xenograft tumor growth in athymic nude mice bearing HCT116 cells. The xenograft tumor size was significantly reduced when the animals were treated with PPD (30 mg/kg body weight) for 3 weeks. When the expression of previously identified Rg3 targets, A kinase (PRKA) anchor protein 8 (AKAP8L) and phosphatidylinositol transfer protein α (PITPNA), was analyzed, PPD was shown to inhibit the expression of PITPNA while upregulating AKAP8L expression in HCT116 cells. Pathway-specific reporter assays indicated that PPD effectively suppressed the NF-κB, JNK and MAPK/ERK signaling pathways. Taken together, our results suggest that the anticancer activity of PPD in colon cancer cells may be mediated through targeting NF-κB, JNK and MAPK/ERK signaling pathways, although the detailed mechanisms underlying the anticancer mode of PPD action need to be fully elucidated.

Compound K, a Ginsenoside Metabolite, Inhibits Colon Cancer Growth via Multiple Pathways Including p53-p21 Interactions

Compound K (20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol, CK), an intestinal bacterial metabolite of ginseng protopanaxadiol saponins, has been shown to inhibit cell growth in a variety of cancers. However, the mechanisms are not completely understood, especially in colorectal cancer (CRC). A xenograft tumor model was used first to examine the anti-CRC effect of CK in vivo. Then, multiple in vitro assays were applied to investigate the anticancer effects of CK including antiproliferation, apoptosis and cell cycle distribution. In addition, a qPCR array and western blot analysis were executed to screen and validate the molecules and pathways involved. We observed that CK significantly inhibited the growth of HCT-116 tumors in an athymic nude mouse xenograft model. CK significantly inhibited the proliferation of human CRC cell lines HCT-116, SW-480, and HT-29 in a dose- and time-dependent manner. We also observed that CK induced cell apoptosis and arrested the cell cycle in the G1 phase in HCT-116 cells. The processes were related to the upregulation of p53/p21, FoxO3a-p27/p15 and Smad3, and downregulation of cdc25A, CDK4/6 and cyclin D1/3. The major regulated targets of CK were cyclin dependent inhibitors, including p21, p27, and p15. These results indicate that CK inhibits transcriptional activation of multiple tumor-promoting pathways in CRC, suggesting that CK could be an active compound in the prevention or treatment of CRC.