ABSTRACT
Garcinia picrorhiza, a woody plant native to Sulawesi and Maluku Islands, Indonesia, has been traditionally used as a wound healing ointment. In our continuous search for bioactive compounds from this plant, 15 phenolic compounds were isolated from its stem bark, including a previously undescribed dihydroisocoumarin, 2'-hydroxyannulatomarin, and two undescribed furanoxanthones, gerontoxanthone C hydrate and 3'-hydroxycalothorexanthone. The structures of the new metabolites were elucidated on the basis of spectroscopic analysis, including 1D and 2D NMR and HRESIMS. Gerontoxanthone C hydrate possessed cytotoxicity against four cancer cells (KB, HeLa S3, MCF-7, and Hep G2) with IC50 values ranging from 5.6 to 7.5 µM. Investigation on the anti-inflammatory activities showed that 3'-hydroxycalothorexanthone inhibited NO production in RAW 264.7 and BV-2 cell lines with IC50 values of 16.4 and 13.8 µM, respectively, whereas only (-)-annulatomarin possessed inhibition activity on COX-2 enzyme over 10% at 20 µM. This work describes the presence of 3,4-dihydroisocoumarin structures with a phenyl ring substituent at C-3, which are reported the first time in genus Garcinia. These findings also suggest the potential of furanxanthone derivatives as cytotoxic and anti-inflammatory agents for further pharmacological studies.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Isocoumarins/pharmacology , Xanthones/pharmacology , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/isolation & purification , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Line , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Isocoumarins/chemistry , Isocoumarins/isolation & purification , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Mice , Molecular Structure , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/biosynthesis , Xanthones/chemistry , Xanthones/isolation & purificationABSTRACT
Eight new polyprenylated benzoylphloroglucinol derivatives (1-8) and four known analogues (9-12) were isolated from the stem bark of Garcinia picrorhiza. Their structures were determined by spectroscopic data analysis (1D and 2D NMR and HRESIMS), and the absolute configurations were established by single-crystal X-ray diffraction combined with experimental and calculated ECD data. The new metabolites represent rare examples of benzoylphloroglucinols bearing a cyclobutyl-containing side chain. The isolated compounds were evaluated for their cytotoxic properties against five types of human cancer cells (KB, HeLa S3, MCF-7, Hep G2, and HT-29 cells) and their inhibitory activities against COX-1 and COX-2 enzymes. The cytotoxicity results showed that compound 6 was active against KB, HeLa S3, MCF-7, and Hep G2 cancer cells, with IC50 values ranging from 5.9 to 9.4 µM. Among the compounds tested for cyclooxygenase inhibition, compound 8 possessed the highest inhibitory effect toward COX-1 (35.2 ± 9.6% inhibition at 20 µM).
Subject(s)
Phloroglucinol/chemistry , Phloroglucinol/isolation & purification , Plant Bark/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Drug Screening Assays, Antitumor , Humans , Spectrum Analysis/methodsABSTRACT
Within non-communicable diseases, chronic inflammatory conditions represent one of the biggest challenges for modern medicine. Traditional Chinese Medicine (TCM) has been practiced over centuries and has accumulated tremendous empirical knowledge on the treatment of such diseases. Huangqi Jianzhong Tang (HQJZT) is a famous TCM herbal formula composed of Radix Astragali, Ramulus Cinnamomi, Radix et Rhizoma Glycyrrhizae Praeparata cum Melle, Radix Paeoniae Alba, Rhizoma Zingiberis Recens, Fructus Jujubae and Saccharum Granorum (maltose), which has been used for the treatment of various chronic inflammatory gastrointestinal diseases. However, there is insufficient knowledge about its active constituents and the mechanisms responsible for its effects. The present study aimed at identifying constituents contributing to the bioactivity of HQJZT by combining in vitro cytokine production assays and LC-MS metabolomics techniques. From the HQJZT decoction as well as from its single herbal components, extracts of different polarities were prepared. Phytochemical composition of the extracts was analyzed by means of UPLC-QTOF-MS/MS. The inhibitory effects of the extracts on TNF-α, IL-1ß and IFN-γ production were studied in U937 cells. Phytochemical and pharmacological bioactivity data were correlated by orthogonal projection to latent structures discriminant analysis (OPLS-DA) in order to identify those HQJZT constituents which may be relevant for the observed pharmacological activities. The investigations resulted in the identification of 16 HQJZT constituents, which are likely to contribute to the activities observed in U937 cells. Seven of them, namely calycosin, formononetin, astragaloside I, liquiritigenin, 18ß-glycyrrhetinic acid, paeoniflorin and albiflorin were unambiguously identified. The predicted results were verified by testing these compounds in the same pharmacological assays as for the extracts. In conclusion, the anti-inflammatory activity of HQJZT could be substantiated by in vitro pharmacological screening, and the predicted activities of the OPLS-DA hits could be partially verified. Moreover, the benefits and limitations of MVDA for prediction pharmacologically active compounds contributing to the activity of a TCM mixture could be detected.
Subject(s)
Anti-Inflammatory Agents/chemistry , Cytokines/metabolism , Drugs, Chinese Herbal/chemistry , Lipopolysaccharides/adverse effects , Metabolomics/methods , Anti-Inflammatory Agents/pharmacology , Chromatography, Liquid , Cytokines/drug effects , Drug Evaluation, Preclinical , Drugs, Chinese Herbal/pharmacology , Gene Expression Regulation/drug effects , Humans , Interferon-gamma/metabolism , Interleukin-1beta/metabolism , Tandem Mass Spectrometry , Tumor Necrosis Factor-alpha/metabolism , U937 CellsABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Medicinal properties of hyssop have been used in traditional medicine since ancient times, inter alia, in diseases/conditions with an inherent inflammatory process. AIM OF THE STUDY: Accordingly, the aim of this study was to investigate the anti-inflammatory properties of hyssop herb preparations (essential oil and methanol extracts) in vivo, in vitro and in silico. MATERIALS AND METHODS: For in vitro testing of essential oils and extracts of hyssop herb, the cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) enzyme assays were used. In vivo anti-inflammatory potential of the extracts (at doses of 50, 100 and 200 mg/kg) was assessed using the carrageenan-induced rat paw edema test. Molecular docking and dynamics were used for in silico testing of the inhibitory activity of chlorogenic (CA) and rosmarinic (RA) acids, as the dominant compounds in the tested methanol extracts against COX-1 and COX-2 enzymes. RESULTS: Significant inhibitory activity was shown in the COX-2 test regarding extracts (essential oils did not exhibit any significant activity). Namely, all analyzed extracts, at a concentration of 20 µg/mL, showed a percentage of inhibition of COX-2 enzyme (54.04-63.04%), which did not indicate a statistically significant difference from the positive control of celecoxib (61.60%) at a concentration of 8.8 µM. In vivo testing showed that all methanol extracts of hyssop herb, at the highest test dose of 200 mg/kg in the third and fourth hours, after carrageenan administration, exhibited a statistically significant (p < 0.05) inhibitory effect on the increase in rat paw edema in relation to control. This activity is comparable or higher in relation to the reference substance, indomethacin, at a concentration of 8 mg/kg. The preliminary in silico results suggest that investigated compounds (RA and CA) showed better inhibitory activity against COX-1 and COX-2 than standard non-steroidal anti-inflammatory drug (NSAID), ibuprofen, as evident from the free binding energy (ΔGbind in kJ mol-1). The binding energies of the docked compounds to COX-1 and -2 were found to be in the range between -47.4 and -49.2 kJ mol-1. Ibuprofen, as the one NSAID, for the same receptors targets, showed remarkably higher binding energy (ΔGbind = -31.3 kJ mol-1 to COX-1, and ΔGbind = -30.9 kJ mol-1 to COX-2). CONCLUSION: The results obtained not only support the traditional use of hyssop herb in inflammatory conditions in folk medicine, but also open the door to and the need for further in vivo testing of extracts in order to examine the molecular mechanism of anti-inflammatory activity in living systems and possibly develop a new anti-inflammatory drug or supplement.