ABSTRACT
In our search for immune stimulating materials from natural source, bioassay-guided fractionation of a methanol extract of Panax ginseng leaves led to the isolation of three dammarane triterpenes (1-3), including two previously unknown compounds 27-demethyl-(E,E)-20(22),23-dien-3ß,6α,12ß-trihydroxydammar-25-one (1) and 3ß,20(S)-dihydroxydammar-24-en-12ß,23ß-epoxy-20-O-ß-D-glucopyranoside (2). Their structures were elucidated on the basis of spectroscopic methods, chemical transformation, and by the comparison with those of literature data. Compounds 1-3 significantly increased interleukin-12 expression in LPS-activated mouse peritoneal macrophage at a concentration of 100 ng/mL. Furthermore, compound 1 strongly increased the Th1 response-mediated cytokine IL-2, and decreased Th2 response-mediated cytokines IL-4 and IL-6 expression at 100 ng/mL on ConA-activated splenocytes. This study indicated that compound 1 showed a better effect on cellular immunity, and provided new chemical entities as promising lead compounds for the treatment of cellular immunity-related diseases.
Subject(s)
Panax/chemistry , Plant Leaves/chemistry , Triterpenes/chemistry , Animals , Chemistry, Physical , Female , Immunity, Cellular , Mice , Mice, Inbred BALB C , Plant Extracts/analysis , Plants, Medicinal , Triterpenes/immunology , Triterpenes/isolation & purification , DammaranesABSTRACT
Panax ginseng is considered as one of the most valuable medicinal herbs in traditional medicine, and ginsenoside Rd is one of the main active ingredients in P. ginseng leaf. Although there is significant number of evidences implicated on the beneficial effects of the ginsenosides with diverse associated mechanisms, reports on the skin regeneration by the ginsenoside Rd are not sufficient. Therefore, we examined the mitogenic and protective effects of the ginsenoside Rd in the keratinocyte progenitor cells (KPCs) and human dermal fibroblasts (HDFs). Furthermore, the signaling pathways involved in the activation of KPCs and HDFs were investigated, and wound-healing effect is evaluated in vivo through animal wound models. We found that the ginsenoside Rd significantly increased the proliferation and migration level of KPCs and HDFs in a dose-dependent manner. Additionally, the cell survival was significantly increased in H2O2 treated KPCs. Moreover, the ginsenoside Rd effectively induced collagen type 1 and down-regulated matrix metalloprotinase-1 (MMP-1) in a dose-dependent manner. All of these beneficial effects are associated with an induction of intracellular cAMP levels and phosphorylated cAMP response element-binding protein expression in nucleus, which both attenuated by adenine 9-ß-d-arabinofuranoside, an adenylate cyclase inhibitor. Application of the ginsenoside Rd to an excision wound in mice showed an effective healing process. As skin regeneration is mainly associated with the activation of HDFs and KPCs, P. ginseng leaf, an alternative source of the ginsenoside Rd, can be used as a natural source for skin regeneration.
Subject(s)
Cyclic AMP-Dependent Protein Kinases/metabolism , Fibroblasts/drug effects , Ginsenosides/pharmacology , Phytotherapy , Stem Cells/drug effects , Wound Healing/drug effects , Animals , Cell Movement/drug effects , Cell Proliferation/drug effects , Collagen/metabolism , Cyclic AMP Response Element-Binding Protein/metabolism , Female , Fibroblasts/metabolism , Ginsenosides/therapeutic use , Humans , Keratinocytes/cytology , Matrix Metalloproteinase 1/metabolism , Mice , Mice, Hairless , Panax , Plant Leaves/chemistry , Signal Transduction , Skin/cytology , Stem Cells/metabolismABSTRACT
To our knowledge, there is no report that directly shows an inhibitory effect of ginsenoside on melanin synthesis in B16 melanoma cells. Hence, we investigated whether the aglycone of Rh(4) (A-Rh4) inhibits melanin synthesis in B16 melanoma cells, and determined the mechanism of melanin inhibition. We isolated 12 ginsenoside compounds from leaves of Panax ginseng and tested them in B16 melanoma cells. It significantly reduced melanin content and tyrosinase activity under alpha-melanocyte stimulating hormone- and forskolin-stimulated conditions. It significantly reduced the cyclic AMP (cAMP) level in B16 melanoma cells, and this might be responsible for the regulation down of MITF and tyrosinase. Phosphorylation of a downstream molecule, a cAMP response-element binding protein, was significantly decreased according to Western blotting and immunofluorescence assay. These data suggest that A-Rh4 has an anti-melanogenic effect via the protein kinase A pathway.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cyclic AMP-Dependent Protein Kinases/genetics , Ginsenosides/pharmacology , Melanins/antagonists & inhibitors , Monophenol Monooxygenase/antagonists & inhibitors , Panax/chemistry , Signal Transduction/drug effects , Animals , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Line, Tumor , Colforsin/pharmacology , Cyclic AMP/metabolism , Cyclic AMP Response Element-Binding Protein/genetics , Cyclic AMP Response Element-Binding Protein/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Ginsenosides/isolation & purification , Melanins/biosynthesis , Melanoma, Experimental/metabolism , Mice , Microphthalmia-Associated Transcription Factor/genetics , Microphthalmia-Associated Transcription Factor/metabolism , Monophenol Monooxygenase/metabolism , Phosphorylation/drug effects , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Plant Leaves/chemistry , alpha-MSH/pharmacologyABSTRACT
Four new terpenylated coumarins (1-4) were isolated from the stem bark of Ailanthus altissima by bioactivity-guided fractionation using an in vitro SIRT1 deacetylation assay. Their structures were identified as (2'R,3'R)-7-(2',3'-dihydroxy-3',7'-dimethylocta-6'-enyloxy)-6,8-dimethoxycoumarin (1), 6,8-dimethoxy-7-(3',7'-dimethylocta-2',6'-dienyloxy)coumarin (2), (2'R,3'R,6'R)-7-(2',3'-dihydroxy-6',7'-epoxy-3',7'-dimethyloctaoxy)-6,8-dimethoxycoumarin (3), and (2'R,3'R,4'S,5'S)-6,8-dimethoxy-7-(3',7'-dimethyl-4',5'-epoxy-2'-hydroxyocta-6'-enyloxy)coumarin (4). Compounds 1-4 strongly enhanced SIRT1 activity in an in vitro SIRT1-NAD/NADH assay and an in vivo SIRT1-p53 luciferase assay. These compounds also increased the NAD-to-NADH ratio in HEK293 cells. The present results suggest that terpenylated coumarins from A. altissima have a direct stimulatory effect on SIRT1 deacetylation activity and may serve as lead molecules for the treatment of some age-related disorders.
Subject(s)
Ailanthus/chemistry , Coumarins/isolation & purification , Sirtuin 1/drug effects , Amino Acid Sequence , Coumarins/chemistry , Humans , Luciferases/drug effects , Luciferases/metabolism , Molecular Structure , NAD/analysis , NAD/metabolism , Nuclear Magnetic Resonance, Biomolecular , Plant Bark/chemistry , Plant Stems/chemistry , Republic of Korea , StereoisomerismABSTRACT
Four new ent-kaurane diterpenoids (1-4) were isolated from the leaves of Croton tonkinensis by bioactivity-guided fractionation using an in vitro osteoblast differentiation assay. Their structures were identified as ent-11ß-acetoxykaur-16-en-18-ol (1), ent-11α-hydroxy-18-acetoxykaur-16-ene (2), ent-14ß-hydroxy-18-acetoxykaur-16-ene (3), and ent-7α-hydroxy-18-acetoxykaur-16-ene (4). Compounds 1-4 significantly increased alkaline phosphatase activity and osteoblastic gene promoter activity. Compounds 1-3 also increased the levels of ALP and collagen type I alpha mRNA in C2C12 cells in a dose-dependent manner. These results suggest that ent-kaurane diterpenoids from C. tonkinensis have a direct stimulatory effect on osteoblast differentiation and may be potential therapeutic molecules against bone diseases such as osteoporosis.
