Niga-ichigoside F1 Research Articles

Niga-ichigoside F1 alleviates DSS-induced ulcerative colitis by inhibiting the NF-κB pathway

Niga-ichigoside F1, an ursolic acid-type pentacyclic triterpenoid, possesses various pharmacological properties, including anti-tumor, anti-inflammatory, and antinociceptive potentials. However, its function and underlying mechanism in ulcerative colitis (UC) remain unknown. Hence, this study aimed to explore the effect of Niga-ichigoside F1 on dextran sulfate sodium (DSS)-induced colitis. The predictive results of network pharmacology identified 311 common targets of Niga-ichigoside F1 and ulcerative colitis. The 4 highest-scoring genes were screened by the BottleNeck method and they were, signal transducer and activator of transcription 3 (STAT3), tumor necrosis factor (TNF), protein kinase B gamma (AKT3), and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit beta (PIK3CB). KEGG pathway analysis indicated that Niga-ichigoside F1 probably exerted a protective effect on UC through the nuclear factor-kappa B (NF-κB) pathways. Molecular docking results showed that Niga-ichigoside F1 had a high affinity for nuclear factor-kappa B-inhibitor of nuclear factor-kappa B (NF-κB-IκB) complex, with the lowest binding energy. Furthermore, our results in vivo showed that Niga-ichigoside F1 alleviated weight loss, colon shortening, disease activity index (DAI), and histological scoring in DSS-induced colitis mice. Moreover, Niga-ichigoside F1 decreased the levels of inflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and interleukin-8 (IL-8) and the expression of oxidative stress markers nitric oxide (NO), myeloperoxidase (MPO), and malonaldehyde (MDA) to mitigate inflammation and intestinal damage. Western blotting results evidenced that Niga-ichigoside F1 intervention significantly regulated the NF-κB pathway. In conclusion, this study highlighted the potential of Niga-ichigoside F1 in ameliorating colitis, indicating its potential application as a functional food.

Cytogenotoxic screening of the natural compound niga-ichigoside F1 from Rubus imperialis (Rosaceae).

Rubus imperialis Chum. Schl. (Rosaceae) have demonstrated some pharmacological activities, including gastroprotective action. However, genotoxic effects of R. imperialis extract was also reported. Since niga-ichigoside F1 (NIF1) is a major compound of this plant species, and which has proven pharmacological properties, it is essential to investigate whether this compound is responsible for the observed toxicity. Therefore, the objective of this study was to analyze the effects of NIF1 on HepG2/C3A cells for possible cytogenotoxicity, cell cycle and apoptosis influence, and expression of genes linked to the DNA damage, cell cycle, cell death, and xenobiotic metabolism. The results showed no cytogenotoxic effects of NIF1 at concentrations between 0.1 and 20 μg/ml. Flow cytometry also showed no cell cycle or apoptosis disturbance. In the gene expression analysis, none of the seven genes investigated showed altered expression. The data indicate that NIF1 has no cytogenotoxic effects, and no interruption of the cell cycle, or induction of apoptosis, apparently not being responsible for the cytotoxic effects observed in the crude extract of R. imperialis.

Secondary metabolites from the leaves of Terminalia myriocarpa and their α-glucosidase inhibitory potential

The objective of this study is to investigate the chemical composition of the leaves of Terminalia myriocarpa and to evaluate their α-glucosidase inhibitory activity aiming to be used as a safe antidiabetic. Consequently, 10 compounds were isolated using column and preparative thin-layer chromatographic techniques and identified as alphitolic acid, isovitexin, flavogallonic acid, nigaichigoside F1, quercetin, quadranoside IV, rosamultin, 19α-hydroxyasiatic acid, asiatic acid, and arjunic acid. Structure elucidation was based on chemical (acid hydrolysis) and spectroscopic (UV, 1 H, and 13C-NMR) analyses and findings were confirmed through comparison with published data. The α-glucosidase inhibitory activity of the methanol extract fractions and compounds isolated therefrom was evaluated in-vitro alongside that of acarbose (positive control). Results revealed that quercetin and flavogallonic acid were significantly active with half-maximal inhibitory concentrations (IC50) equal to 7.5 ± 0.09 and 21.0 ± 1.4 µM, respectively. Furthermore, the interaction of lavogallonic acid with α-glucosidase enzyme was verified by docking experiment. Accordingly, quercetin and flavogallonic acid could be considered safer natural alternatives to the currently availableα-glucosidase inhibitors.

Metabolites of Geum aleppicum and Sibbaldianthe bifurca: Diversity and α-Glucosidase Inhibitory Potential.

α-Glucosidase inhibitors are essential in the treatment of diabetes mellitus. Plant-derived drugs are promising sources of new compounds with glucosidase-inhibiting ability. The Geum aleppicum Jacq. and Sibbaldianthe bifurca (L.) Kurtto & T.Erikss. herbs are used in many traditional medical systems to treat diabetes. In this study, metabolites of the G. aleppicum and S. bifurca herbs in active growth, flowering, and fruiting stages were investigated using high-performance liquid chromatography with photodiode array and electrospray ionization triple quadrupole mass spectrometric detection (HPLC-PDA-ESI-tQ-MS/MS). In total, 29 compounds in G. aleppicum and 41 components in S. bifurca were identified including carbohydrates, organic acids, benzoic and ellagic acid derivatives, ellagitannins, flavonoids, and triterpenoids. Gemin A, miquelianin, niga-ichigoside F1, and 3,4-dihydroxybenzoic acid 4-O-glucoside were the dominant compounds in the G. aleppicum herb, while guaiaverin, miquelianin, tellimagrandin II2, casuarictin, and glucose were prevailing compounds in the S. bifurca herb. On the basis of HPLC activity-based profiling of the G. aleppicum herb extract, the most pronounced inhibition of α-glucosidase was observed for gemin A and quercetin-3-O-glucuronide. The latter compound and quercetin-3-O-arabinoside demonstrated maximal inhibition of α-glucosidase in the S. bifurca herb extract. The obtained results confirm the prospects of using these plant compounds as possible sources of hypoglycemic nutraceuticals.

Role of extracted phytochemicals from Rosa sterilis S. D. Shi in DSS-induced colitis mice: potential amelioration of UC.

Rosa sterilis S. D. Shi is a new variety of R. roxburghii Tratt and its fruits are rich in bioactive components, but its effects and mechanisms against intestinal inflammation are currently unknown. In this study, the main components of the ethanol extract of R. sterilis S. D. Shi fruits (RSE) were identified and its anti-inflammatory efficacy in DSS-induced mice was evaluated. A total of nine compounds were identified, including 1-O-E-cinnamoyl-(6-arabinosylglucose), ellagic acid-O-rhamnoside, (epi) catechin, niga-ichigoside F1, etc. The results demonstrated that RSE ameliorated DSS-induced inflammation in mouse colon tissues by increasing mucin expression, reducing the production of TNF-α, IL-1β, and IL-6, inhibiting the mRNA expression of COX-2 and iNOS, regulating the composition of gut microbiota through suppressing Escherichia-Shigella while increasing Akkermansia muciniphila, and promoting the production of SCFAs, especially acetic acid. Briefly, RSE showed outstanding potential for anti-inflammatory activity and is expected to be a promising dietary supplement for healthy individuals to prevent or relieve colitis and colitis-related diseases, which provided a new direction for functional food development.

Triterpenoids from strawberry Fragaria × ananassa Duch. cultivar Senga Sengana leaves

Senga Sengana is a common strawberry (Fragaria × ananassa Duch.) cultivar growing in southern Poland. From leaves of this popular horticultural plant six triterpenoids were obtained including one glycoside nigaichigoside F1. All compounds were isolated by repeated silica gel column chromatography and preparative HPLC on Reverse phase RP-18. Their structures were evaluated by modern HR-MS and NMR techniques. This is the first report concerning triterpenoids constituents in Senga Sengana cultivar leaves and the only one that describes isolation of these compounds from the strawberry leaves. From all compounds nigaichigoside F1 is the dominant constituent. Compound T1 (3β, 19α, 23α-trihydroxy-2-oxoolean-12-en-28-oic acid) is a new triterpenoid, not previously described in nature. As triterpenoids are responsible for many biological effects the strawberry leaf extracts enriched in triterpenoid constituents may also be involved in antifungal, antitumor, antidiabetic and antinociceptive activities. The latter two activities could be especially linked to the presence of euscaphic acid and nigaichigoside F1, respectively. Overall, this study suggests that strawberry leaves are a promising waste and a valuable source of bioactive compounds for the food and pharmaceutical industry.

Two new oleanane triterpenoid saponins from Elsholtzia bodinieri

Two new oleanane triterpenoid saponins, bodiniosides Q (1) and R (2), along with five known saponins, niga-ichigoside F1 (3), 3-O-[β-D-glucopyranosyl]-28-O-[α-L-rhamnopyranosyl -(1→2)-β-D-glucopyranosyl] arjunolic acid (4), asiaticoside E (5), sericoside (6), and bodinioside E (7), were isolated from the aerial parts of Elsholtzia bodinieri. The structures of 1 and 2 were characterized by spectroscopic techniques and chemical evidence as 3-O-β-D- xylopyranosyl-2α, 23-dihydroxy-olean-12-en-28-oic acid 28-O-α-L-rhamnopyranosyl- (1→2)-β-D-glucopyranoside (1) and 3-O-β-D-xylopyranosyl-2α, 23-dihydroxy-olean-12-en-28-oic acid 28-O-[β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl -(1→2)]-β-D-glucopyranoside (2). Compounds 1, 3, and 5 exhibited weak anti-influenza activity against strain A/WSN/33/2009 (H1N1), with inhibition rate of 11.63%, 17.01%, and 16.98%, respectively.

Antiplasmodial activity of triterpenes isolated from the methanolic leaf extract of Combretum racemosum P. Beauv.

Combretum racemosum showed activity in previous ethnopharmacological investigations of some Combretum species used in malaria treatment in parts of West Africa. This study aimed at confirming the antimalarial potential of this plant by an activity-guided isolation of its active principles. A crude methanolic leaf extract of Combretum racemosum and fractions thereof obtained by partition with chloroform and n-butanol were investigated for antiplasmodial activity against chloroquine-sensitive (D10) and chloroquine-resistant (W2) strains of Plasmodium falciparum. Repeated chromatographic separations were conducted on the chloroform fraction to isolate bioactive compounds for further tests on antiplasmodial activity. The characterization of the isolated substances was performed by applying NMR- and MS-techniques (ESI-MS, HR-ESIMS, 1D and 2D NMR). The chloroform fraction (D10: IC50 = 33.8 ± 1.5 μg/mL and W2: IC50 = 27.8 ± 2.9 μg/mL) exhibited better antiplasmodial activity than the n-butanol fraction (D10: IC50 = 78.1 ± 7.3 μg/mL and W2: IC50 = 78 ± 15 μg/mL) as well as the methanolic raw extract (D10: IC50 = 64.2 ± 2.7 μg/mL and W2: IC50 = 65.8 ± 14.9 μg/mL). Thus, the focus of the phytochemical investigation was laid on the chloroform fraction, which led to the identification of four ursane-type (19α-hydroxyasiatic acid (1), 6β,23-dihydroxytormentic acid (4), madecassic acid (8), nigaichigoside F1 (10)) and four oleanane-type (arjungenin (2), combregenin (5), terminolic acid (7), arjunglucoside I (11)) triterpenes, as well as abscisic acid (9). Compounds 1 and 2, 4 and 5, 7 and 8 as well as 10 and 11 were isolated as isomeric mixtures in fractions CR-A, CR-C, CR-E and CR-H, respectively. All isolated compounds and mixtures exhibited moderate to low activity, with madecassic acid being most active (D10: IC50 = 28 ± 12 μg/mL and W2: IC50 = 17.2 ± 4.3 μg/mL). This paper reports for the first time antiplasmodial principles from C. racemosum and thereby gives reason to the traditional use of the plant.

New antimicrobial triterpene glycosides from lemon balm (Melissa officinalis)

The ever-growing demand for new and safe antimicrobials for the prevention and treatment of clinical and foodborne pathogens has stimulated considerable research interest into Lamiaceae plants as natural antimicrobial agents and food preservatives. Among them, lemon balm (Melissa officinalis L.) has been recently emerged as a promising food additive owing to its outstanding antimicrobial and food preserving capacities, particularly of its polar extracts and aqueous decoctions. Consequently, in this work, investigation of the polar/hydrophilic antimicrobial constituents of the medicinally and culinary used aerial parts of lemon balm has resulted in the isolation and identification of three new ursene triterpene glycosides; melissiosides A–C (1–3), along with the known triterpenoidal glycoside 23-sulfate ester of niga-ichigoside F1 (4). Compounds 1–4 demonstrated varied antimicrobial activities in comparison with the tested antimicrobial standards using the agar diffusion assay, especially against Gram-negative bacteria and yeast. These results highlight the potential of lemon balm as a promising source of natural antimicrobials and alternative food preservatives, which largely contribute to its nutritherapeutic, pharmaceutical, and food-related applications in the future.

Niga-ichigoside F1 ameliorates high-fat diet-induced hepatic steatosis in male mice by Nrf2 activation.

Hepatic lipid accumulation and oxidative stress (OS) lead to non-alcoholic fatty liver disease (NAFLD). Thus, we hypothesized that antihyperlipidemic and antioxidant activities of niga-ichigoside F1 (NI) would ameliorate events leading to NAFLD. Lanbuzheng (Geum japonicum Thunb. var. chinense), a type of wild vegetable found in Southwest China, was used to extract NI. Male C57BL/6J mice were fed a standard diet (Con) or a high-fat diet (HFD) (denoted as diet) with or without 40 mg kg-1 NI (defined as treatment) for 12 weeks. Diet-treatment interactions were observed in the final body weight, fat pad mass, respiratory exchange ratio (RER) in the daytime, and energy expenditure during the whole day. Moreover, NI alleviated hepatic steatosis, possibly by significantly interacting with HFD to regulate lipid metabolism genes (including Srebp1c, Acc1, Fasn, Scd1, Cpt1a and Fabp5). We also found significant diet-treatment interactions on superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) activities, and thiobarbituric acid reactive substance (TBARS) levels, as well as the nuclear and cellular Nrf2 protein levels. Significant free fatty acid (FFA)-treatment interactions on Nrf2 nuclear translocation, antioxidant enzymes activities, genes in lipogenesis (Srebp1c, Acc1, Fasn, and Scd1), and fatty acid oxidation (Pparα) and transport (Fabp5 and Cd36) were also detected in 1 mM FFA-treated HepG2 cells with or without 20 μM NI. These beneficial effects of NI on oxidative stress and lipid accumulation were abolished by Nrf2 siRNA. Our data revealed that dietary NI could prevent HFD-induced hepatic steatosis, possibly via interacting with HFD to activate Nrf2 nuclear translocation to maintain a redox status, thus regulating lipid metabolism genes expressions.

Antimicrobial and antioxidant potential of different solvent extracts of the medicinal plant Geum urbanum L.

Many Geum species are known to be rich in biologically active compounds and therefore could be a source of new natural products with pharmacological potential. The medicinal plant Geum urbanum L. is widespread in Bulgaria and has been used in folk medicine. In the present study, the methanol extracts of the roots and aerial parts of G. urbanum and their fractions (petroleum ether, ethyl acetate and n-butanol) were investigated for antibacterial and radical scavenging activity. The ethyl acetate and n-butanol fractions inhibited the growth of Gram-positive pathogenic and opportunistic bacteria from the genus Staphylococcus (MIC EtOAc: 0.078 mg/ml aerial and 0.156 mg/ml roots; MIC n-BuOH: 0.156 mg/ml aerial and 1.25 mg/ml roots) and the species Bacillus cereus stronger than the other extracts and fractions tested (MIC EtOAc: 0.078 mg/ml aerial and 0.156 mg/ml roots; MIC n-BuOH: 0.156 mg/ml aerial and 0.078 mg/ml roots), and showed corresponding radical scavenging activity (EtOAc: EC50 1.5 µg/ml aerial, 0.8 µg/ml roots; n-BuOH: 4.5 µg/ml aerial; 3.7 µg/ml roots). Additionally, their total phenolic content was quantified (% of dry EtOAc fractions of roots 61%, of arial parts 32%; of dry n-BuOH fractions of roots 16%, of arial parts 13%). Seven compounds were isolated and identified spectroscopically from the ethyl acetate extract. Two acetylated ellagic acid rhamnosides were found for the first time in the genus Geum and three others, tormentic acid, niga-ichigoside F1, and 3,3′-di-O-methylellagic acid-4-O-β-d-glucopyranoside, were newly detected for the species G. urbanum. Our results reveal that G. urbanum L. is a perspective medicinal plant and deserves further, more detailed studies.

Rubus imperialis (Rosaceae) extract and pure compound niga-ichigoside F1: wound healing and anti-inflammatory effects.

Here, we evaluate the anti-inflammatory and wound-healing effects of methanolic crude extract obtained from aerial parts (leaves and branches) of Rubus imperialis Chum. Schl. (Rosaceae) and the pure compound niga-ichigoside F1. Anti-inflammatory activity was determined in vivo and in vitro, and the healing effect was evaluated in surgical lesions in mice skin. The 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) assay and H2O2-induced oxidative stress were used to determine antioxidant activity. The efferocytosis activity was also determined. The data obtained show that the extract of R. imperialis promote reduction in the inflammatory process induced by lipopolysaccharide (LPS) or carrageenan in the air pouch model; the effects could be reinforced by nitric oxide reduction in LPS-stimulated neutrophils, and an increase in the efferocytosis. The extract showed wound healing property in vitro and in vivo, scavenging activity for DPPH, and cytoprotection in the H2O2-induced oxidative stress in L929 cells. In addition, the compound niga-ichigoside F1 was able to reduce the NO secretion; however, it did not present wound-healing activity in vitro. Together, the data obtained point out the modulatory actions of R. imperialis extract on leukocyte migration to the inflamed tissue, the antioxidant, and the pro-resolutive activity. However, the R. imperialis anti-inflammatory activity may be mediated in parts by niga-ichigoside F1, and on wound healing do not correlated with niga-ichigoside F1.

In vivo evaluation of the genetic toxicity of Rubus niveus Thunb. (Rosaceae) extract and initial screening of its potential chemoprevention against doxorubicin-induced DNA damage

Ethnopharmacological relevanceRubus niveus Thunb. plant belongs to Rosaceae family and have been used traditionally to treat wounds, burns, inflammation, dysentery, diarrhea and for curing excessive bleeding during menstrual cycle. The present study was undertaken to investigate the in vivo genotoxicity of Rubus niveus aerial parts extract and its possible chemoprotection on doxorubicin (DXR)-induced DNA damage. In parallel, the main phytochemicals constituents in the extract were determined. Materials and methodsThe animals were exposed to the extract for 24 and 48h, and the doses selected were 500, 1000 and 2000mg/kg b.w. administered by gavage alone or prior to DXR (30mg/kg b.w.) administered by intraperitoneal injection. The endpoints analyzed were DNA damage in bone marrow and peripheral blood cells assessed by the alkaline alkaline (pH>13) comet assay and bone marrow micronucleus test. Results and conclusionThe results of chemical analysis of the extract showed the presence of tormentic acid, stigmasterol, quercitinglucoronide (miquelianin) and niga-ichigoside F1 as main compounds. Both cytogenetic endpoints analyzed showed that there were no statistically significant differences (p>0.05) between the negative control and the treated groups with the two higher doses of Rubus niveus extract alone, demonstrating absence of genotoxic and mutagenic effects. Aneugenic/clastogenic effect was observed only at 2000mg/kg dose. On the other hand, in the both assays and all tested doses were observed a significant reduction of DNA damage and chromosomal aberrations in all groups co-treated with DXR and extract compared to those which received only DXR. These results indicate that Rubus niveus aerial parts extract did not revealed any genotoxic effect, but presented some aneugenic/clastogenic effect at higher dose; and suggest that it could be a potential adjuvant against development of second malignant neoplasms caused by the cancer chemotherapic DXR.

New terpenoid glycosides obtained from Rosmarinus officinalis L. aerial parts

Five new terpenoid glycosides, named as officinoterpenosides A1 (1), A2 (2), B (3), C (4), and D (5), together with 11 known ones, (1S,4S,5S)-5-exo-hydrocamphor 5-O-β-d-glucopyranoside (6), isorosmanol (7), rosmanol (8), 7-methoxyrosmanol (9), epirosmanol (10), ursolic acid (11), micromeric acid (12), oleanolic acid (13), niga-ichigoside F1 (14), glucosyl tormentate (15), and asteryunnanoside B (16), were obtained from the aerial parts of Rosmarinus officinalis L. Their structures were elucidated by chemical and spectroscopic methods (UV, IR, HRESI-TOF-MS, 1D and 2D NMR). Among the new ones, 1 and 2, 3 and 4 are diterpenoid and triterpenoid glycosides, respectively; and 5 is a normonoterpenoid. For the known ones, 6 was isolated from the Rosmarinus genus first, and 15, 16 were obtained from this species for the first time.

Evaluation of the gastroprotective activity of the extracts, fractions, and pure compounds obtained from aerial parts of Rubus imperialis in different experimental models

Previous phytochemical studies carried out with Rubus imperialis Chum. Schl. (Rosaceae) have demonstrated the presence of triterpenes (niga-ichigoside F1 and 2β,3β,19α-trihydroxyursolic acid) in this species. The literature indicates that triterpenes are closely related to some pharmacological activities, including antiulcer activity. Therefore, in view of the previous promising results with this species, this work extends the phytochemical studies, as well as investigates its gastroprotective action in different models using rodents. The hydroalcoholic extract was tested using the following protocols in mice: ethanol/HCl and nonsteroidal anti-inflammatory drug (NSAID)-induced ulcer, acetic acid-induced chronic ulcer, ligature pylorus model, and free mucus quantification in mucosa. Isolated triterpenes were investigated in the ethanol/HCl-induced ulcer model. The results of this study show that R. imperialis extract (100, 250, or 500mg) displays gastroprotective activity in the ethanol-induced ulcer model with a percentage of inhibition of gastric lesions of 70, 71, and 86%, respectively. The extract also significantly reduced the ulcerative lesions in the indomethacin-induced ulcer. In this model, the percentage of inhibition of ulcer was 41, 44, and 70%, respectively. Regarding the model of gastric secretion, a reduction of gastric juice volume and total acidity was observed, as well as an increase in gastric pH; however, gastric mucus production was not altered by treatment with the extract. It was also observed that the ethyl acetate fraction presented higher activity, leading to the isolation of niga-ichigoside F1 and 2β,3β-19-α-trihydroxyursolic acid, which presented antiulcer activity comparable to that of omeprazole, with an inhibition percentage of 98 and 99%, respectively. These results demonstrate that R. imperialis extract and isolated compounds (niga-ichigoside F1 and 2β,3β-19-α-trihydroxyursolic acid) produce gastroprotective effects, and this activity seems, at least in part, to be related to antisecretory effects.

Bioactivity-Guided Fractionation of Physical Fatigue-Attenuating Components from Rubus parvifolius L.

Alleviation of fatigue has been emerging as a serious issue that requires urgent attention. Health professionals and sports physiologists have been looking for active natural products and synthetic compounds to overcome fatigue in humans. This study was designed to define the anti-fatigue property of Rubus parvifolius L. (RPL) by characterization of active constituents using a mouse forced swimming test model. Four RPL fractions with different polarities containing anti-fatigue activity were sequentially isolated from the n-butanol RPL extract, followed by elution of 50% ethanol-water fraction from D101 macroporous resin chromatography to obtain nigaichigoside F1, suavissimoside R1 and coreanoside F1. Active constituents of the 50% ethanol-water eluate of RPL were total saponins. The fractions were examined based on the effect on weight-loaded swimming capacity of mice. Serum levels of urea nitrogen (SUN), triglyceride fatty acids (TG), lactate dehydrogenase (LDH), lactic acid (LA), ammonia and hepatic glycogen (HG) were also examined for potential mechanisms underlying the anti-fatigue effect of RPL extracts. During the experiment, two inflammatory markers, interleukin-6 (IL-6) and tumor necrosis factor (TNF-α) in serum, were measured. We found that total saponins from RPL possess potent capabilities to alleviate mouse fatigue induced by forced swimming and that nigaichigoside F1 was responsible for the pharmacological effect. The underlying mechanisms include delays of SUN and LA accumulation, a decrease in TG level by increasing fat consumption, increases in HG and LDH so that lactic acid accumulation and ammonia in the muscle were reduced, and suppression of increased immune activation and inflammatory cytokine production. Our findings will be helpful for functional identification of novel anti-fatigue components from natural medicinal herbs.

Anti-Helicobacter pylori Activity of the Methanolic Extract of Geum iranicum and its Main Compounds

Geum iranicum Khatamsaz, belonging to the Rosaceae family, is an endemic plant of Iran. The methanol extract of the roots of this plant showed significant activity against one of the clinical isolates of Helicobacter pylori which was resistant to metronidazole. The aim of this study was the isolation and evaluation of the major compounds of G. iranicum effective against H. pylori. The compounds were isolated using various chromatographic methods and identified by spectroscopic data (1H and 13C NMR, HMQC, HMBC, EI-MS). An antimicrobial susceptibility test was performed employing the disk diffusion method against clinical isolates of H. pylori and a micro dilution method against several Gram-positive and Gram-negative bacteria; additionally the inhibition zone diameters (IZD) and minimum inhibitory concentrations (MIC) values were recorded. Nine compounds were isolated: two triterpenoids, uvaol and niga-ichigoside F1, three sterols, beta-sitosterol, beta-sitosteryl acetate, and beta-sitosteryl linoleate, one phenyl propanoid, eugenol, one phenolic glycoside, gein, one flavanol, (+)-catechin, and sucrose. The aqueous fraction, obtained by partitioning the MeOH extract with water and chloroform, was the most effective fraction of the extract against all clinical isolates of H. pylori. Further investigation of the isolated compounds showed that eugenol was effective against H. pylori but gein, diglycosidic eugenol, did not exhibit any activity against H. pylori. The subfraction D4 was the effective fraction which contained tannins. It appeared that tannins were probably the active compounds responsible for the anti-H. pylori activity of G. iranicum. The aqueous fraction showed a moderate inhibitory activity against both Gram-positive and Gram-negative bacteria. The MIC values indicated that Gram-positive bacteria including Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus subtilis are more susceptible than Gram-neagative bacteria including Escherichia coli and Pseudomonas aeruginosa.

23-Hydroxytormentic Acid and Niga-Ichgoside F1 Isolated from Rubus coreanus Attenuate Cisplatin-Induced Cytotoxicity by Reducing Oxidative Stress in Renal Epithelial LLC-PK1 Cells

The unripe fruits of Rubus coreanus (Rosaceae) are used in traditional Chinese medicine to relieve kidney dysfunction. In the present study, we evaluated the protective effects of the triterpenoid glycoside niga-ichigoside F₁ (NIF₁) and of its aglycone 23-hydroxytormentic acid (23-HTA) isolated from the unripe fruits of Rubus coreanus (Rosaceae) against cisplatin-induced cytotoxicity in renal epithelial LLC-PK₁ cells. Pretreating LLC-PK₁ cells with 23-HTA or NIF₁ was found to prevent cisplatin-induced cytotoxicity and apoptosis. In addition, 23-HTA or NIF₁ pretreatment significantly improved the changes associated with cisplatin toxicity by increasing levels of glutathione (GSH) and decreasing levels of malondialdehyde (MDA) and reactive oxygen species (ROS). The activity of antioxidant enzymes including catalase (CAT) and superoxide dismutase (SOD) was significantly lower in cisplatin-treated LL-PK₁ cells, and 23-HTA or NIF₁ treatment notably increased the these enzyme activity and protein and mRNA levels of CAT and manganese SOD (MnSOD). Moreover, cisplatin caused a significant decrease in nuclear levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and pretreatment with 23-HTA or NIF₁ significantly suppressed the cisplatin-induced translocation of Nrf2 in LLC-PK₁ cells. Taken together, these results suggest that 23-HTA ameliorates cisplatin-induced toxicity via modulation of antioxidant enzymes through activation of Nrf2 in LLC-PK₁ cells.

The Ameliorative Effect of 23-Hydroxytormentic Acid Isolated from Rubus coreanus on Cisplatin-Induced Nephrotoxicity in Rats

Previously, the authors demonstrated that the triterpenoid glycoside niga-ichigoside F₁ (NIF₁) and its aglycone 23-hydroxytormentic acid (23-HTA) isolated from the unripe fruits of Rubus coreanus (Rosaceae) ameliorate cisplatin-induced toxicity in renal epithelial LLC-PK₁ cells. In the present study, the nephroprotective effects of NIF₁ and 23-HTA were investigated in Sprague-Dawley rats with acute renal injury induced by a single intraperitoneal (i.p.) injection of cisplatin (7 mg/kg). Pretreatment with 23-HTA (10 mg/kg/d, per os (p.o.)) significantly reduced cisplatin-induced elevations in blood urea nitrogen (BUN) and serum creatinine level, whereas NIF₁ (10 mg/kg, p.o.) slightly reduced these levels. In addition, pretreatment with 23-HTA prevented cisplatin-induced hydroxyl radical generation, malondialdehyde (MDA) production, glutathione (GSH) depletion, and cisplatin-induced changes in the activities of oxidant and antioxidant enzymes in rat renal tissues. In addition, histopathological examinations showed that 23-HTA pretreatment reduced cisplatin-induced acute tubular necrosis and histological changes. In contrast, NIF₁ was found to have a slight or no influence on cisplatin-induced oxidative enzymes and acute tubular necrosis. Taken together, these results suggest that protective effect of 23-HTA pretreatment on cisplatin-induced renal damage is associated with the attenuation of oxidative stress and the preservation of antioxidant enzymes.

Analysis of the mechanism of antinociceptive action of niga-ichigoside F1 obtained from Rubus imperialis (Rosaceae)

We have previously verified that niga-ichigoside F(1) (NI), a triterpene isolated from Rubus imperialis, exhibits significant and potent antinociceptive action when evaluated in some pharmacological models of pain in mice. This effect was confirmed in other experimental models and also the mechanism of action has been evaluated. The antinociception caused by NI (60 mg kg(-1)) in both phases of the formalin test was significantly attenuated by intraperitoneal injection of mice with haloperidol (a dopaminergic antagonist, 0.20 mg kg(-1)) and L-arginine (precursor of nitric oxide, 600 mg kg(-1)). Regarding the cholinergic system, atropine (a cholinergic antagonist 60 mg kg(-1)) reverted only the second phase. The effect of NI was not affected by treatment of mice with yohimbine (an alpha2-adrenoceptor antagonist, 0.15 mg kg(-1)). The same pharmacological profile was observed for the administration of naloxone (an opioid receptor antagonist, 1 mg kg(-1)). On the other hand, intraperitoneal injection caused dose-related and significant effects against glutamate- and capsaicin-induced pain, respectively. In conclusion, the marked antinociception of NI appears to be related to the dopaminergic, cholinergic, glutamatergic, tachykininergic and oxinitrergic systems, supporting the ethnomedical use of Rubus imperialis (Rosaceae).