Chemical studies on oriental plant drugs. XIV. Protopanaxadiol, a genuine sapogenin of ginseng saponins

Ameliorative Effects of Korean-Red-Ginseng-Derived Polysaccharide on Antibiotic-Associated Diarrhea

This study evaluated the ameliorative effects of Korean-red-ginseng-derived polysaccharide (KRG-P) on antibiotic-associated diarrhea (AAD) induced by administering lincomycin in mice. Changes of intestinal barrier proteins, the intestinal microbiome and short-chain fatty acid (SCFA) contents were investigated. Lincomycin was orally administered for 9 days to induce diarrhea; subsequently, 100 mg/kg and 300 mg/kg of KRG-P were administered orally for 12 days. The diarrhea was observed in the AAD group; further KRG-P administration improved the diarrhea. Analysis of changes in the intestinal microbial flora of the mice revealed that the harmful bacterial flora (such as Proteobacteria) were increased in the AAD group, whereas beneficial bacterial flora (such as Firmicutes) were decreased. However, KRG-P administration resulted in decreased Proteobacteria and increased Firmicutes, supporting the improvement of the microbial flora imbalance caused by AAD. Moreover, an analysis of the SCFAs (acetic acid, propionic acid, and butylic acid) in the caecum revealed that SCFAs' contents in the AAD group were substantially reduced but tended to increase upon KRG-P administration. Based on these results, KRG-P, which is primarily composed of carbohydrates can improve lincomycin-induced diarrhea, likely owing to the recovery of SCFA content by improving the intestinal microbial imbalance and intestinal barrier proteins.

Heat Treatment Enhances the Neuroprotective Effects of Crude Ginseng Saponin by Increasing Minor Ginsenosides

Ginsenoside is the primary active substance of ginseng and has many pharmacological effects, such as anti-cancer, immune, regulating sugar and lipid metabolism, and antioxidant effects. It also protects the nervous and cardiovascular systems. This study analyzes the effects of thermal processing on the bioactivities of crude ginseng saponin. Heat treatment increased the contents of minor ginsenosides in crude saponins, such as Rg3, and heat-treated crude ginseng saponin (HGS) had better neuroprotective effects than non-treated crude saponin (NGS). HGS reduced glutamate-induced apoptosis and reactive oxygen species generation in pheochromocytoma 12 (PC12) cells, significantly more than NGS. HGS protected PC12 cells against glutamate-induced oxidative stress by upregulating Nrf2-mediated antioxidant signaling and downregulating MAPK-mediated apoptotic signaling. HGS has the potential for the prevention and treatment of neurodegenerative disorders, such as Alzheimer's and Parkinson's disease.

New magnetic nanocomposite Fe3O4@Saponin/Cu(II) as an effective recyclable catalyst for the synthesis of aminoalkylnaphthols via Betti reaction

In this research, a new magnetic nanocomposite Fe₃O₄@Saponin/Cu(II) based on quillaja saponin was prepared and the catalyst structure was characterized thoroughly using FT-IR, EDS, TGA, XRD, VSM, HR-TEM, SEM, ICP, BET analyzes. The catalyst prepared in the three-component synthesis of several Betti bases, 1-(α-aminoalkyl)naphthols, under environmentally friendly conditions was used. The advantage of this reaction is the high efficiency of the products and the short reaction time. Furthermore, Fe₃O₄@Saponin/Cu(II) nano-catalyst is recoverable magnetically and is reusable for other processes with no reduction in its activity.

Experimental Evidence for the Anti-Metastatic Action of Ginsenoside Rg3: A Systematic Review

Cancer metastasis is the leading cause of death in cancer patients. Due to the limitations of conventional cancer treatment, such as chemotherapy, there is a need for novel therapeutics to prevent metastasis. Ginsenoside Rg3, a major active component of Panax ginseng C.A. Meyer, inhibits tumor growth and has the potential to prevent tumor metastasis. Herein, we systematically reviewed the anti-metastatic effects of Rg3 from experimental studies. We searched for articles in three research databases, MEDLINE (PubMed), EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) through March 2022. In total, 14 studies (eight animal and six in vitro) provide data on the anti-metastatic effects of Rg3 and the relevant mechanisms. The major anti-metastatic mechanisms of Rg3 involve cancer stemness, epithelial mesenchymal transition (EMT) behavior, and angiogenesis. Taken together, Rg3 would be one of the herbal resources in anti-metastatic drug developments through further well-designed investigations and clinical studies. Our review provides valuable reference data for Rg3-derived studies targeting tumor metastasis.

Rapid Identification of Characteristic Chemical Constituents of Panax ginseng, Panax quinquefolius, and Panax japonicus Using UPLC-Q-TOF/MS

Saponins are the main active components in Panax ginseng C. A. Mey. (PG), Panax quinquefolius L. (PQ), and Panax japonicus C. A. Mey. (PJ), which belong to the genus Panax in the Araliaceae family. Because the chemical components in the three species are similar, they are often mixed and misused in functional foods and pharmaceuticals applications. Therefore, it is urgent to establish a method to quickly distinguish among PG, PQ, and PJ. Ultraperformance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) was combined with data postprocessing to identify the main characteristic fragments (CFs) and the related neutral losses (NLs) of protopanaxadiol (PPD), protopanaxatriol (PPT), oleanolic acid (OLE), and ocotillol- (OCO-) type saponins. By comparing the mass spectral data, it was possible to rapidly classify and identify saponins in PG, PQ, and PJ. A total of twenty-three chemical components were identified in the PG samples, twenty-three components were identified in the PQ samples, and twenty-seven components were identified in the PJ samples. Among them, OCO-type saponins were characteristic of PQ and PJ. Ginsenoside Rf, which was absent from PQ, allowed for differentiation between PQ and PJ. The CFs and NLs in the mass spectra of the characteristic components of PG, PQ, and PJ allowed for the rapid classification and identification of these species. Additionally, these results provide technical support for the quality evaluation of Chinese herbal medicine and for constructing a scientific regulatory system.

The promising therapeutic potentials of ginsenosides mediated through p38 MAPK signaling inhibition

The p38 mitogen-activated protein kinases (p38 MAPK) is a 38kD polypeptide recognized as the target for many potential anti-inflammatory agents. Accumulating evidence indicates that p38 MAPK could perform many roles in human disease pathophysiology. Therefore, great therapeutic benefits can be attained from p38 MAPK inhibitors. Ginseng is an exceptionally valued medicinal plant of the family Araliaceae (Panax genus). Recently, several studies targeted the therapeutic effects of purified individual ginsenoside, the most significant active ingredient of ginseng, and studied its particular molecular mechanism(s) of action rather than whole-plant extracts. Interestingly, several ginsenosides: ginsenosides compound K, F1, Rb1, Rb3, Rc, Rd, Re, Rf, Rg1, Rg2, Rg3, Rg5, Rh1, Rh2, Ro, notoginsenoside R1, and protopanaxadiol have shown to possess great therapeutic potentials mediated by their ability to downregulate p38 MAPK signaling in different cell lines and experimental animal models. Our review compiles the research findings of various ginsenosides as potent anti-inflammatory agents, highlighting the crucial role of p38 MAPK suppression in their pharmacological actions. In addition, in silico studies were conducted to explore the probable binding of these ginsenosides to p38 MAPK. The results obtained proposed p38 MAPK involvement in the beneficial pharmacological activities of ginsenosides in different ailments.

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p38 MAPK plays many roles in human disease pathophysiology. Therefore, great therapeutic benefits can be attained from p38 MAPK inhibitors.

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Several ginsenosides showed to possess great therapeutic potentials mediated by its ability to downregulate p38 MAPK signaling.

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in silico ​studies were conducted to explore the binding of these ginsenosides to p38 MAPK and evidenced the promising their inhibitory effect.

Development of Broad-Spectrum Antiviral Agents-Inspiration from Immunomodulatory Natural Products

Developing broad-spectrum antiviral drugs remains an important issue as viral infections continue to threaten public health. Host-directed therapy is a method that focuses on potential targets in host cells or the body, instead of viral proteins. Its antiviral effects are achieved by disturbing the life cycles of pathogens or modulating immunity. In this review, we focus on the development of broad-spectrum antiviral drugs that enhance the immune response. Some natural products present antiviral effects mediated by enhancing immunity, and their structures and mechanisms are summarized here. Natural products with immunomodulatory effects are also discussed, although their antiviral effects remain unknown. Given the power of immunity and the feasibility of host-directed therapy, we argue that both of these categories of natural products provide clues that may be beneficial for the discovery of broad-spectrum antiviral drugs.

Advances in Saponin Diversity of Panax ginseng

Ginsenosides are the major bioactive constituents of Panax ginseng, which have pharmacological effects. Although there are several reviews in regards to ginsenosides, new ginsenosides have been detected continually in recent years. This review updates the ginsenoside list from P. ginseng to 170 by the end of 2019, and aims to highlight the diversity of ginsenosides in multiple dimensions, including chemical structure, tissue spatial distribution, time, and isomeride. Protopanaxadiol, protopanaxatriol and C17 side-chain varied (C17SCV) manners are the major types of ginsenosides, and the constitute of ginsenosides varied significantly among different parts. Only 16 ginsenosides commonly exist in all parts of a ginseng plant. Protopanaxadiol-type ginsenoside is dominant in root, rhizome, leaf, stem, and fruit, whereas malonyl- and C17SCV-type ginsenosides occupy a greater proportion in the flower and flower bud compared with other parts. In respects of isomeride, there are 69 molecular formulas corresponding to 170 ginsenosides, and the median of isomers is 2. This is the first review on diversity of ginsenosides, providing information for reasonable utilization of whole ginseng plant, and the perspective on studying the physiological functions of ginsenoside for the ginseng plant itself is also proposed.

Physiological and pharmacological features of the non-saponin components in Korean Red Ginseng

Panax ginseng, a medicinal plant, has been used as a blood-nourishing tonic for thousands of years in Asia, including Korea and China. P. ginseng exhibits adaptogen activity that maintains homeostasis by restoring general biological functions and non-specifically enhancing the body's resistance to external stress. Several P. ginseng effects have been reported. Korean Red Ginseng, in particular, has been reported in both basic and clinical studies to possess diverse effects such as enhanced immunity, fatigue relief, memory, blood circulation, and anti-oxidation. Moreover, it also protects against menopausal symptoms, cancer, cardiac diseases, and neurological disorders. The active components found in most Korean Red Ginseng varieties are known to include ginsenosides, polysaccharides, peptides, alkaloids, polyacetylene, and phenolic compounds. In this review, the identity and bioactivity of the non-saponin components of Korean Red Ginseng discovered to date are evaluated and the components are classified into polysaccharide and nitrogen compounds (protein, peptide, amino acid, nucleic acid, and alkaloid), as well as fat-soluble components such as polyacetylene, phenols, essential oils, and phytosterols. The distinct bioactivity of Korean Red Ginseng was found to originate from both saponin and non-saponin components rather than from only one or two specific components. Therefore, it is important to consider saponin and non-saponin elements together.

Ginsenoside 20(S)-protopanaxadiol induces cell death in human endometrial cancer cells via apoptosis

Background

20(S)-protopanaxadiol (20(S)-PPD), one of the aglycone derivatives of major ginsenosides, has been shown to have an anticancer activity toward a variety of cancers. This study was initiated with an attempt to evaluate its anti-cancer activity toward human endometrial cancer by cell and xenograft mouse models.

Methods

Human endometrial cancer (HEC)-1A cells were incubated with different 20(S)-PPD concentrations. 20(S)-PPD cytotoxicity was evaluated using MTT assay. Apoptosis was detected using the annexin V binding assay and cell cycle analysis. Cleaved poly (ADP-ribose) polymerase (PARP) and activated caspase-9 were assessed using western blotting. HEC-1A cell tumor xenografts in athymic mice were generated by inoculating HEC-1A cells into the flank of BALB/c female mice and explored to validate 20(S)-PPD anti-endometrial cancer toxicity.

Results

20(S)-PPD inhibited HEC-1A cell proliferation in a dose-dependent manner with an IC₅₀ value of 3.5 μM at 24 h. HEC-1A cells morphologically changed after 20(S)-PPD treatment, bearing resemblance to Taxol-treated cells. Annexin V-positive cell percentages were 0%, 10.8%, and 58.1% in HEC-1A cells when treated with 0, 2.5, and 5 μM of 20(S)-PPD, respectively, for 24 h. 20(S)-PPD subcutaneously injected into the HEC-1A cell xenograft-bearing mice three times a week for 17 days manifested tumor growth inhibition by as much as 18% at a dose of 80 mg/kg, which sharply contrasted to controls that showed an approximately 2.4-fold tumor volume increase. These events paralleled caspase-9 activation and PARP cleavage.

Conclusion

20(S)-PPD inhibits endometrial cancer cell proliferation by inducing cell death via a caspase-mediated apoptosis pathway. Therefore, the 20(S)-PPD-like ginsenosides are endowed with ample structural information that could be utilized to develop other ginsenoside-based anticancer agents.

Dammarane-type leads panaxadiol and protopanaxadiol for drug discovery: Biological activity and structural modification

Based on the definite therapeutic benefits, such as neuroprotective, cardioprotective, anticancer, anti-diabetic and so on, the Panax genus which contains many valuable plants, including ginseng (Panax ginseng C.A. Meyer), notoginseng (Panax notoginseng) and American ginseng (Panax quinquefolius L.), attracts research focus. Actually, the biological and pharmacological effects of the Panax genus are mainly attributed to the abundant ginsenosides. However, the low membrane permeability and the gastrointestinal tract influence seriously limit the absorption and bioavailability of ginsenosides. The acid or base hydrolysates of ginsenosides, 20 (R,S)-panaxadiol and 20 (R,S)-protopanaxadiol showed improved bioavailability and diverse pharmacological activities. Moreover, relative stable skeletons and active hydroxyl group at C-3 position and other reactive sites are suitable for structural modification to improve biological activities. In this review, the pharmacological activities of panaxadiol, protopanaxadiol and their structurally modified derivatives are comprehensively summarized.

Modification of ginsenoside composition in red ginseng (Panax ginseng) by ultrasonication

The result of USRG-12 indicated that ultrasonication-processed (100°C, 12 h) red ginseng extracts had the highest amount of ginsenosides Rg3 (0.803%), Rg5 (0.167%), and Rk1 (0.175%).

Changes in the contents of prosapogenin in Red ginseng (Panax ginseng) depending on the extracting conditions

This study compared the contents of prosapogenin depending on the extracting conditions of Red ginseng to provide basic information for developing Red ginseng-based functional foods. The content of ginsenoside Rg3 reached their maximum value at 24 h of extraction, followed by 36 h and 72 h of extraction at 100°C.

Chemical diversity of ginseng saponins from Panax ginseng

Ginseng, a perennial plant belonging to the genus Panax of the Araliaceae family, is well known for its medicinal properties that help alleviate pathological symptoms, promote health, and prevent potential diseases. Among the active ingredients of ginseng are saponins, most of which are glycosides of triterpenoid aglycones. So far, numerous saponins have been reported as components of Panax ginseng, also known as Korean ginseng. Herein, we summarize available information about 112 saponins related to P. ginseng; >80 of them are isolated from raw or processed ginseng, and the others are acid/base hydrolysates, semisynthetic saponins, or metabolites.

Saponins in the genus Panax L. (Araliaceae): a systematic review of their chemical diversity

The Panax genus is a crucial source of natural medicines that has benefited human health for a long time. Three valuable medicinal herbs, namely Panax ginseng, Panax quinquefolius, and Panax notoginseng, have received considerable interest due to their extensive application in clinical therapy, healthcare products, and as foods and food additives world-wide. Panax species are known to contain abundant levels of saponins, also dubbed ginsenosides, which refer to a series of dammarane or oleanane type triterpenoid glycosides. These saponins exhibit modulatory effects to the central nervous system and beneficial effects to patients suffering from cardiovascular diseases, and also have anti-diabetic and anti-tumor properties. To the end of 2012, at least 289 saponins were reported from eleven different Panax species. This comprehensive review describes the advances in the phytochemistry of the genus Panax for the period 1963-2012, based on the 134 cited references. The reported saponins can be classified into protopanaxadiol, protopanaxatriol, octillol, oleanolic acid, C17 side-chain varied, and miscellaneous subtypes, according to structural differences in sapogenins. The investigational history of Panax is also reviewed, with special attention being paid to the structural features of the six different subtypes, together with their (1)H and (13)C NMR spectroscopic characteristics which are useful for determining their structures and absolute configuration.

Major repeat components covering one-third of the ginseng (Panax ginseng C.A. Meyer) genome and evidence for allotetraploidy

Ginseng (Panax ginseng) is a famous medicinal herb, but the composition and structure of its genome are largely unknown. Here we characterized the major repeat components and inspected their distribution in the ginseng genome. By analyzing three repeat-rich bacterial artificial chromosome (BAC) sequences from ginseng, we identified complex insertion patterns of 34 long terminal repeat retrotransposons (LTR-RTs) and 11 LTR-RT derivatives accounting for more than 80% of the BAC sequences. The LTR-RTs were classified into three Ty3/gypsy (PgDel, PgTat and PgAthila) and two Ty1/Copia (PgTork and PgOryco) families. Mapping of 30-Gbp Illumina whole-genome shotgun reads to the BAC sequences revealed that these five LTR-RT families occupy at least 34% of the ginseng genome. The Ty3/Gypsy families were predominant, comprising 74 and 33% of the BAC sequences and the genome, respectively. In particular, the PgDel family accounted for 29% of the genome and presumably played major roles in enlargement of the size of the ginseng genome. Fluorescence in situ hybridization (FISH) revealed that the PgDel1 elements are distributed throughout the chromosomes along dispersed heterochromatic regions except for ribosomal DNA blocks. The intensity of the PgDel2 FISH signals was biased toward 24 out of 48 chromosomes. Unique gene probes showed two pairs of signals with different locations, one pair in subtelomeric regions on PgDel2-rich chromosomes and the other in interstitial regions on PgDel2-poor chromosomes, demonstrating allotetraploidy in ginseng. Our findings promote understanding of the evolution of the ginseng genome and of that of related species in the Araliaceae.

Protective effect of ginsenoside Re on acute gastric mucosal lesion induced by compound 48/80

The protective effect of ginsenoside Re, isolated from ginseng berry, against acute gastric mucosal lesions was examined in rats with a single intraperitoneal injection of compound 48/80 (C48/80). Ginsenoside Re (20 mg/kg or 100 mg/kg) was orally administered 0.5 h prior to C48/80 treatment. Ginsenoside Re dose-dependently prevented gastric mucosal lesion development 3 h after C48/80 treatment. Increases in the activities of myeloperoxidase (MPO; an index of neutrophil infiltration) and xanthine oxidase (XO) and the content of thiobarbituric acid reactive substances (TBARS; an index of lipid peroxidation) and decreases in the contents of hexosamine (a marker of gastric mucus) and adherent mucus, which occurred in gastric mucosal tissues after C48/80 treatment, were significantly attenuated by ginsenoside Re. The elevation of Bax expression and the decrease in Bcl2 expression after C48/80 treatment were also attenuated by ginsenoside Re. Ginsenoside Re significantly attenuated all these changes 3 h after C48/80 treatment. These results indicate that orally administered ginsenoside Re protects against C48/80-induced acute gastric mucosal lesions in rats, possibly through its stimulatory action on gastric mucus synthesis and secretion, its inhibitory action on neutrophil infiltration, and enhanced lipid peroxidation in the gastric mucosal tissue.

Effects of Minor Ginsenosides, Ginsenoside Metabolites, and Ginsenoside Epimers on the Growth of Caenorhabditis elegans

In the previous report, we have demonstrated that ginsenoside Rc, one of major ginsenosides, is a major component for the restoration for normal growth of worms in cholesterol-deprived medium. In the present study, we further investigated the roles of minor ginsenosides, such as ginsenoside Rh₁ and Rh₂, ginsenoside metabolites such as compound K (CK), protopanaxadiol (PPD), and protopanaxatriol (PPT) and ginsenoside epimers such as 20(R)- and 20(S)-ginsenoside Rg₃ in cholesterol-deprived medium. We found that ginsenoside Rh₁ almost restored normal growth of worms in cholesterol-deprived medium in F1 generation. However, supplement of ginsenoside Rh₂ caused a suppression of worm growths in cholesterol-deprived medium. In addition, CK and PPD also slightly restored normal growth of worms in cholesterol-deprived medium but PPT not. In experiments using ginsenoside epimers, supplement of 20(S)- but not 20(R)-ginsenoside Rg₃ in cholesterol-deprived medium also almost restored worm growth. These results indicate that the absence or presence of carbohydrate component at backbone of ginsenoside, the number of carbohydrate attached at carbon-3, and the position of hydroxyl group at carbon-20 of ginsenoside might plays important roles in restoration of worm growth in cholesterol-deprived medium.

Changes in the Contents of Prosapogenin in the Red Ginseng (Panax ginseng) Depending on Steaming Batches

This study compared the contents of ginsenosides depending on steaming conditions of red ginsengs to provide basic information for developing functional foods using red ginsengs. The red ginseng steamed eight times at 98℃ ranked atop the amounts of prosapogenins ever detected in red ginsengs (ginsenoside Rg₂, Rg₃, Rg₅, Rg₆, Rh₁, Rh₄, Rk₁, Rk₃, F₁, F₄, 1.15%) among red ginsengs steamed more than twice. When steamed eight times at 98℃, 2.7 times as much prosapogenins such as ginsenosides Rg₂, Rg₃, Rg₅, Rg₆, Rh₁, Rh₄, Rk₁, Rk₃, F₁, and F₄ as those steamed just once at 98℃ was collected. In addition, the red ginsengs steamed eight times at 98℃ contained more amounting ginsenoside Rg₃ (0.28%) than that in the red ginseng steamed several times at random. Accordingly, it is recommendable that red ginsengs steamed 8 times, which proved to be the optimal steaming condition, be used rather than those steamed 9 times (black ginsengs), in order to develop red ginseng products of high prosapogenin concentration and high functions.

Four new triterpenoid saponins from the leaves of Panax japonicus grown in southern Miyazaki Prefecture (4)

Four new dammarane-type triterpenoid saponins such as chikusetsusaponin LM3 (1), chikusetsusaponin LM4 (2), chikusetsusaponin LM5 (3), chikusetsusaponin LM6 (4), and twenty known triterpenoid saponins such as ginsenoside Rb3 (5), ginsenoside Rc (6), ginsenoside Rd (7), ginsenoside Re (8), ginsenoside Rg1 (9), ginsenoside F3 (10), ginsenoside F5 (11), ginsenoside F6 (12), chikusetsusaponin IVa (13), chikusetsusaponin V (14), chikusetsusaponin L5 (15), chikusetsusaponin L9a (16), chikusetsusaponin L9bc (17), chikusetsusaponin L10 (18), chikusetsusaponin FK2 (19), chikusetsusaponin FK6 (20), chikusetsusaponin FK7 (21), chikusetsusaponin FT1 (22), chikusetsusaponin LM1 (23), and chikusetsusaponin LM2 (24), were isolated from the leaves of Panax japonicus C. A. MEYER collected in Miyazaki prefecture, Japan. The structures of new chikusetsusaponins were elucidated on the basis of spectral and physicochemical evidences.

Inhibitory effects of ginsenoside re isolated from ginseng berry on histamine and cytokine release in human mast cells and human alveolar epithelial cells

The berry of Panax ginseng significantly inhibited the histamine releases at the concentration of 30 μg/mL (p<0.05) and 10 μg/mL (p<0.01). The ginsenoside Re from ginseng berry was found out to have a potent effect in the experiment of histamin and cytokine release.

Modification of ginseng flavors by bitter compounds found in chocolate and coffee

Ginseng is not widely accepted by U.S. consumers due to its unfamiliar flavors, despite its numerous health benefits. Previous studies have suggested that the bitter compounds in chocolate and coffee may mask the off-flavors of ginseng. The objectives of this study were to: (1) profile sensory characteristics of ginseng extract solution, caffeine solution, cyclo (L-Pro-L-Val) solution, theobromine solution, and 2 model solutions simulating chocolate bitterness; and (2) determine the changes in the sensory characteristics of ginseng extract solution by the addition of the bitter compounds found in chocolate and coffee. Thirteen solutions were prepared in concentrations similar to the levels of the bitter compounds found in coffee and chocolate products. Twelve panelists participated in a descriptive analysis panel which included time-intensity ratings. Ginseng extract was characterized as sweeter, starchier, and more green tea than the other sample solutions. Those characteristics of ginseng extract were effectively modified by the addition of caffeine, cyclo (L-Pro-L-Val), and 2 model solutions. A model solution simulating dark chocolate bitterness was the least influenced in intensities of bitterness by the addition of ginseng extract. Results from time-intensity ratings show that the addition of ginseng extract increased duration time in certain bitterness of the 2 model solutions. Bitter compounds found in dark chocolate could be proposed to effectively mask the unique flavors of ginseng. Future studies blending aroma compounds of chocolate and coffee into such model solutions may be conducted to investigate the influence on the perception of the unique flavors through the congruent flavors.

Preventive effects of protopanaxadiol and protopanaxatriol ginsenosides on liver inflammation and apoptosis in hyperlipidemic apoE KO mice

Ginsenosides, bioactive compounds of Panax Ginseng C.A. Meyer, are divided into protopanaxadiol (PD) and protopanaxtriol (PT). The aim of this study was to evaluate the protective effects of different PD and PT combination ratios on liver inflammation and apoptosis in hyperlipidemic apo E KO mice. R1 (PD/PT = 1, high Rg(1) and Rb(1)) and R2 (PD/PT = 2, high Re and Rd) extracts were intraperitoneally injected by 100 mg/kg/day at the 8th week. R1 and R2 improved atherogenic indices by increasing HDL and lowering total cholesterol (TC) and triacylglyceride (TG) selectively. R1 decreased lipid peroxides (LPO) level in plasma and liver tissue of hyperlipidemic mice, and R2 lowered plasma malondialdehyde(MDA) level. R1 and R2 not only regulated the expression of cyclooxygenase (COX)-2, IκB-α, phopho-ERK 1/2, and phopho-SAPK/JNK levels but also were significantly effective in blocking apoptotic signals, such as caspase-8, -9, as well as the cleavage of PARP in liver. Different combinational treatment of PD and PT extracts might ameliorate the liver inflammation and apoptosis in hyperlipidemic apo E KO mice, which is atherosclerotic animal model.

Ginsenoside Rb1 prevents homocysteine-induced endothelial dysfunction via PI3K/Akt activation and PKC inhibition

Hyperhomocysteinemia (HHcy), a risk factor for cardiovascular disease, is associated with endothelial dysfunction. Ginsenoside Rb1, the major active constituent of ginseng, potently attenuates homocysteine (Hcy)-induced endothelial damage. However, the underlying mechanism remains unknown. In this study, we have investigated the effect of Ginsenoside Rb1 on Hcy-induced endothelial dysfunction and its underlying signal pathway in vivo and in vitro. Ginsenosides prevented Hcy-induced impairment of endothelium-dependent relaxation and Rb1 reversed Hcy-induced reduction of NO production in a dose-dependent manner as detected by nitrate reductase method. Rb1 activated serine-1177 phosphorylation of endothelial nitric oxide synthase (eNOS) and serine-473 phosphorylation of Akt, while inhibited threonine-495 phosphorylation of eNOS as detected by western blotting. Rb1-induced phosphorylation of serine-1177 was significantly inhibited by wortmannin, PI3K inhibitor or SH-5, an Akt inhibitor, and partially reversed by Phorbol 12-myristate 13-acetate (PMA), a PKC activator. PMA also stimulated phosphorylation of threonine-495 which was inhibited by Rb1. Here we show for the first time that Rb1 prevents Hcy-induced endothelial dysfunction via PI3K/Akt activation and PKC inhibition. These findings demonstrate a novel mechanism of the action of Rb1 that may have value in prevention of HHcy associated cardiovascular disease.

Synthesis of protopanaxadiol derivatives and evaluation of their anticancer activities

Protopanaxadiol (PPD), an aglycon of ginseng saponins, has shown anticancer activity in earlier studies. Here, we have reported the semisynthesis of nine PPD derivatives with acetyl substitutions. Subsequently, the antiproliferative effects of these nine analogs on different human cancer cell lines have been investigated. Compounds 1, 3, and 5 showed more significant and more potent antiproliferative activity compared with PPD and other derivatives. A flow cytometric assay indicated that compounds 1, 3, and 5 arrested cell cycle progression in the G1 phase and significantly induced apoptosis of cancer cells.

Identification of 20(S)-protopanaxadiol metabolites in human liver microsomes and human hepatocytes

20(S)-Protopanaxadiol (PPD, 1) is one of the aglycones of the ginsenosides and has a wide range of pharmacological activities. At present, PPD has progressed to early clinical trials as an antidepressant. In this study, its fate in mixed human liver microsomes (HLMs) and human hepatocytes was examined for the first time. By using liquid chromatography-electrospray ionization ion trap mass spectrometry, 24 metabolites were found. Four metabolites were isolated, and their structures were elucidated as (20S,24S)-epoxydammarane-3,12,25-triol (2), (20S,24R)-epoxydammarane-3,12,25-triol (3), (20S,24S)-epoxydammarane-12,25-diol-3-one (4), and (20S,24R)-epoxydammarane-12,25-diol-3-one (5) based on a detailed analysis of their spectroscopic data. The predominant metabolic pathway of PPD observed was the oxidation of the 24,25-double bond to yield 24,25-epoxides, followed by hydrolysis and rearrangement to form the corresponding 24,25-vicinal diol derivatives (M6) and the 20,24-oxide form (2 and 3). Further sequential metabolites (M2-M5) were also detected through the hydroxylation and dehydrogenation of 2 and 3. All of the phase I metabolites except for M1-1 possess a hydroxyl group at C-25 of the side chain, which was newly formed by biotransformation. Two glucuronide conjugates (M7) attributed to 2 and 3 were detected in human hepatocyte incubations, and their conjugation sites were tentatively assigned to the 25-hydroxyl group. The findings of this study strongly suggested that the formation of the 25-hydroxyl group is very important for the elimination of PPD.

Ginsenoside-Rd attenuates oxidative damage related to aging in senescence-accelerated mice

Among the various theories of the aging process, the free radical theory, which proposes that deleterious actions of free radicals are responsible for the functional deterioration associated with aging, has received widespread attention. The theory suggests that enhancement of the antioxidative defence system to attenuate free-radical-induced damage will counteract the aging process. We used senescence-accelerated mice (SAM) to investigate the relationship between aging and the antioxidative defence system and evaluated the effects of ginsenoside-Rd, the saponin from ginseng, by measuring antioxidative defence system parameters, including the glutathione (GSH)/glutathione disulfide (GSSG) redox status, antioxidative enzyme activity and level of lipid peroxidation. SAM at 11 months of age (old SAM) showed a significantly lower hepatic GSH/GSSG ratio, due to decreased GSH and increased GSSG levels, than SAM at 5 weeks of age (young SAM). However, the administration of ginsenoside-Rd at a dose of 1 or 5 mg kg−1 daily for 30 days to 10-month-old SAM significantly increased GSH, but decreased GSSG, resulting in elevation of the GSH/GSSG ratio. In addition, ginsenoside-Rd increased the activity of glutathione peroxidase (GSH-Px) and glutathione reductase that were both significantly lower in old SAM than in young SAM. This suggests that ginsenoside-Rd could play a crucial role in enhancing the defence system through regulation of the GSH/GSSG redox status. Moreover, decreases in the superoxide dismutase (SOD) and catalase activity in old SAM compared with young SAM were also revealed, indicating that the aging process resulted in suppression of the antioxidative defence system. However, ginsenoside-Rd did not affect SOD and catalase activity. As catalase is localized in peroxisome granules and GSH-Px is present in the cytoplasm and mitochondrial matrix, the site of ginsenoside-Rd action may be the cytoplasm and mitochondrial matrix. Furthermore, the serum and liver malondialdehyde levels, indicators of lipid peroxidation, were elevated with aging, while ginsenoside-Rd inhibited lipid peroxidation. This study indicates that the aging process leads to suppression of the antioxidative defence system and accumulation of lipid peroxidation products, while ginsenoside-Rd attenuates the oxidative damage, which may be responsible for the intervention of GSH/GSSG redox status.

Ginsenoside Content of Berries and Roots of Three Typical Korean Ginseng (Panax Ginseng) Cultivars

The ginsenoside content of berries and roots of three cultivars of Korean ginseng have been investigated. For all cultivars, ginsenoside Re was the most abundant ginsenoside in roots and berries. However, berries produced more total ginsenosides, and berry the ginsenoside profile differed from that of roots. The ginsenoside Re content of berries was 4-6 times more than that of roots. Averaged across all cultivars, the amounts of the five ginsenosides in berries was Re > Rc ≈ Rg1 ≈ Rb1 ≈ Rd. For roots, the amounts were Re > Rg1 > Rb1 > Rc >Rd. Roots of the Yunpoong cultivar had the greatest ginsenoside content, followed by roots of the Chunpoong cultivar and the Gumpoong cultivar. The total amount of ginsenosides (especially Rb1, Re, and Rg1) was greatest in the Yunpoong cultivar.

Effect of ginsam, a vinegar extract from Panax ginseng, on body weight and glucose homeostasis in an obese insulin-resistant rat model

Extracts of ginseng species show antihyperglycemic activity. We evaluated the antihyperglycemic and antiobesity effects of ginsam, a component of Panax ginseng produced by vinegar extraction, which is enriched in the ginsenoside Rg3. Otsuka Long-Evans Tokushima Fatty rats, an obese insulin-resistant rat model, were assigned into 1 of 3 groups (n = 8 each): controls (isotonic sodium chloride solution, 5 mL/d), rats given 300 mg/(kg d) ginsam, and rats given 500 mg/(kg d) ginsam. An intraperitoneal 2-hour glucose tolerance test was performed at the end of the 6-week treatment. After 8 weeks, body and liver weights, visceral fat measured by computed tomography, and fasting glucose and insulin concentrations and lipid profiles were recorded. Insulin-resistant rats treated with ginsam had lower fasting and postprandial glucose concentrations compared with vehicle-treated rats. Importantly, overall glucose excursion during the intraperitoneal 2-hour glucose tolerance test decreased by 21.5% (P < .01) in the treated rats, indicating improved glucose tolerance. Plasma insulin concentration was significantly lower in ginsam-treated rats. These changes may be related to increased glucose transporter 4 expression in skeletal muscle. Interestingly, when the data from both ginsam-treated groups were combined, body weight was 60% lower in the ginsam-treated rats than in the controls (P < .01). Liver weight and serum alanine aminotransferase concentrations were also lower in the ginsam-treated rats. These effects were associated with increased peroxisome proliferator-activated receptor gamma expression and adenosine monophosphate-activated protein kinase phosphorylation in liver and muscle. Our data suggest that ginsam has distinct beneficial effects on glucose metabolism and body weight control in an obese animal model of insulin resistance by changing the expression of genes involved in glucose and fatty acid metabolism.

Ginsenosides chemistry, biosynthesis, analysis, and potential health effects

Ginsenosides are a special group of triterpenoid saponins that can be classified into two groups by the skeleton of their aglycones, namely dammarane- and oleanane-type. Ginsenosides are found nearly exclusively in Panax species (ginseng) and up to now more than 150 naturally occurring ginsenosides have been isolated from roots, leaves/stems, fruits, and/or flower heads of ginseng. Ginsenosides have been the target of a lot of research as they are believed to be the main active principles behind the claims of ginsengs efficacy. The potential health effects of ginsenosides that are discussed in this chapter include anticarcinogenic, immunomodulatory, anti-inflammatory, antiallergic, antiatherosclerotic, antihypertensive, and antidiabetic effects as well as antistress activity and effects on the central nervous system. Ginsensoides can be metabolized in the stomach (acid hydrolysis) and in the gastrointestinal tract (bacterial hydrolysis) or transformed to other ginsenosides by drying and steaming of ginseng to more bioavailable and bioactive ginsenosides. The metabolization and transformation of intact ginsenosides, which seems to play an important role for their potential health effects, are discussed. Qualitative and quantitative analytical techniques for the analysis of ginsenosides are important in relation to quality control of ginseng products and plant material and for the determination of the effects of processing of plant material as well as for the determination of the metabolism and bioavailability of ginsenosides. Analytical techniques for the analysis of ginsenosides that are described in this chapter are thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC) combined with various detectors, gas chromatography (GC), colorimetry, enzyme immunoassays (EIA), capillary electrophoresis (CE), nuclear magnetic resonance (NMR) spectroscopy, and spectrophotometric methods.

Antitumor agents. 261. 20(S)-protopanaxadiol and 20(s)-protopanaxatriol as antiangiogenic agents and total assignment of (1)H NMR spectra

Angiogenesis is a critical step in tumor progression and involves several steps including endothelial cell (EC) proliferation, migration, and matrix remodeling. We investigated the antiangiogenic effects of 20( S)-protopanaxadiol ( 1) and 20( S)-protopanaxatriol ( 2), the sapogenins of two major ginseng saponins, in an angiogenesis model of human umbilical vein endothelial cells (HUVECs). These compounds inhibited the proliferative activity of HUVECs in a dose-dependent manner and have potential as anticancer drug candidates. In addition, we report the complete and unambiguous assignment of (1)H NMR spectra of 1 and 2, based on analyses of 2D NMR spectra including COSY, NOESY, HSQC, and HMBC. This report is the first to completely assign the (1)H NMR signals of 2, together with correction of data for 1 from prior reports.

Effects of Homocysteine and Ginsenoside Rb1 on Endothelial Proliferation and Superoxide Anion Production

BACKGROUND

Homocysteine (Hcy) is an independent risk factor for cardiovascular disease by its multiple effects on vascular cells and throbmosis factors, which may be involved in oxidative stress mechansims. Ginsenoside Rb1, a constituent of ginseng, bears various beneficial effects on the cardiovascular system. In the present study, we investigated the effect of Hcy on endothelial proliferation and a protective effect of ginsenoside Rb1 on the action of Hcy.

METHODS

We initially incubated a mouse lymph node endothelial cell line (SVEC4-10) with increasing concentrations of Hcy or for different time periods and then assessed cell proliferation by using [(3)H]-thymidine incorporation. We then incubated SVEC4-10 cells with Hcy (50 microM) for 24 h with or without Rb1 (10 microM) to examine its inhibitory effect on the proliferation. These experiments were repeated in human umbilical vein endothelial cells (HUVECs). To explore the underlying molecular mechanisms, we measured superoxide anion, a reactive oxygen species (ROS), by using dihydroethidium (DHE) staining.

RESULTS

SVEC4-10 cells treated with Hcy (50, 100, and 200 microM) for 24 h significantly reduced cell proliferation by 43%, 42%, and 40%, respectively, as compared with control cells (P < 0.01). SVEC4-10 cells treated with Hcy (50 microM) for 12 and 24 h showed a significant reduction of cell proliferation (P < 0.05). In HUVECs, Hcy (50 microM) significantly reduced cell proliferation by 55% as compared with control cells (P < 0.05). In the presence of Rb1, Hcy-induced inhibition of cell proliferation was effectively blocked in both SVEC4-10 and HUVECs. Furthermore, Hcy (50 microM) significantly increased superoxide anion production by 23% in SVEC4-10 as compared with control cells (P < 0.05). However, in the presence of Rb1, Hcy increased superoxide anion production by only 8%, showing that RB1 almost completely blocked the effect of Hcy.

CONCLUSION

Hcy significantly inhibits endothelial proliferation with increased production of superoxide anion, which is effectively blocked by ginsenoside Rb1. This study provides some new aspects of Hcy-induced endothelial dysfunction, and suggests a potential role of Rb1 to block Hcy action, which may have clinical applications.

Isocratic separation of ginsenosides by high-performance liquid chromatography on a diol column at subambient temperatures

An improved high-performance liquid chromatographic method for separation of a number of ginsenosides has been developed. The influence of temperature (from 0 to 25 degrees C) on the retention and separation of the ginsenosides was studied by applying a binary mobile phase (acetonitrile/water, 82:18 v/v) and a diol column (LiChrospher 100 Diol). The column temperature is one of the more important parameters for the retention and separation of the components investigated. Selected thermodynamic parameters, including changes of enthalpy (deltaH degrees) and entropy (deltaS degrees), were estimated from linear van't Hoff plots, and possible retention mechanisms were discussed. Moreover, the best separation conditions were selected based on optimization criteria including maximum retention time (t(R max)), minimum resolution (R(s min)), and relative resolution product (r). Temperature regions close to 14 degrees C offered the highest selectivity and almost equal distribution of the ginsenosides peaks across the chromatogram. Under such isocratic conditions, excellent separation of chromatographic standards and selected ginseng samples was achieved in less than 16 min.

Ginsenoside Rg3 inhibits phenylephrine-induced vascular contraction through induction of nitric oxide synthase

Ginsenoside Rg3 (Rg3) isolated from Panax ginseng relaxes vessels and exerts a cytoprotective effect. In view of the fact that nitric oxide (NO) is involved in vascular hyporeactivity and immunostimulation, the effects of total ginsenosides (GS) and Rg3 on the vascular responses and the expression of inducible nitric oxide synthase (iNOS) were investigated. Vasocontraction of endothelium-denuded aortic ring was induced by phenylephrine with or without GS or Rg3. The expression of iNOS was assessed by Western blot and RT-PCR analyses. NF-kappaB activation was monitored by gel shift, immunoblot and immunocytochemical analyses. Incubation of the endothelium-denuded aortic ring with GS or Rg3 inhibited phenylephrine-induced vasocontraction, which was abrogated by NOS inhibition. GS or Rg3 increased NO production in aortic rings, but Rb1, Rc, Re and Rg1 had no effect. Aortic rings obtained from rats treated with GS or Rg3 responded to phenylnephrine to a lesser extent, while producing NO to a larger extent, than those from control animals. GS or Rg3 induced iNOS in vascular smooth muscle. Rg3 induced iNOS with increase in NO production in Raw264.7 cells. Rg3 increased NF-kappaB DNA binding, whose band was supershifted with anti-p65 and anti-p50 antibodies, and elicited p65 nuclear translocation, which was accompanied by phosphorylation and degradation of I-kappaBalpha. PKC regulated iNOS induction by Rg3. In conclusion, Rg3 relaxes vessels as a consequence of NO production, to which iNOS induction contributes, and iNOS induction by Rg3 accompanied NF-kappaB activation, which involves phosphorylation and degradation of I-kappaBalpha and nuclear translocation of p65.