• Journal of Life Science
• /
• v.8 no.1
• /
• pp.51-59
• /
• 1998

The apoptosis-inducing activity of ursolic acid (UA) was examined in mouse F9 teratocarcinoma cells on the bases of biochemical and morphological characteeristics. UA, pentacyclic trierpene acid, exhibits antitumor activities including inhibition of skin tumorigenesis, induction of tumor cell differentiation and antitumor promotion. Treatment with UA showed that the decrease of cell viability was dose-dependent. UA also induced genomic DNA fragmetation, a hallmark of apoptosis, indicating that the mechanism of UA-induced F9 cell death was through apoptosis. When the morphology of the F9 cells was examined by electron microscopy, the cells treated with UA showed the charcteristic morphological features of apoptosis such as chromatin condensation and nuclear fragmentation. DNA fragmentations by UA were inhibired by cycloheximide, which suggest that de novo protein synthesis was required for DNA fragmentation by UA. Inaddition, the expression of c-jun was increased, but those of c-myc and laminin B1 were decreased during apoptosis induced by UA in F9 cells. These results suggest that UA causes an apoptosis in F9 cells. Further, the increased expression of c-jun may be involved in the UA-induced apoptosis of f9 cells.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.67 no.4
• /
• pp.335-341
• /
• 2022

Proso millet (Pacnicum miliaceum L.) has a various of functional substances, so the demand is increasing as interest in human health benefits. In particular, miliacin, a triterpenoid in proso millet, is known to be effective in hair loss due to its promoting metabolism and proliferation of keratinocytes and showing protective effects from apoptosis. In this study, proso millet oil was extracted and analyzed by GC/MS using the extraction method of unsaponifiable substances after saponification reaction. The components of proso millet oil were confirmed through qualitative analysis by GC/MS. The miliacin content of 5 varieties of proso millet and 2 varieties of foxtail for comparison was analyzed. In the result, components of pentacyclic triterpenes such as β-amyrine and lupeol were detected in proso millet, and the content of miliacin was highest in Hallachal at 370.38±0.04 ㎍/100 mg oil. In addition, the content of miliacin was not detected in Samdachal and Samdamae, which are varieties of foxtail millet.

• Biomedical Science Letters
• /
• v.19 no.1
• /
• pp.32-40
• /
• 2013

Pluripotent stem cells (PSCs) have enormous potential in the biomedical sciences because they can grow continuously and differentiate into any kind of cell in the body. However, for future application in regenerative medicine, it is still a challenge to control the differentiation of PSCs without using genetic materials. To control the differentiation of PSCs, small molecules might be the best substitute for genetic materials considering the following advantages: small size, which enables penetration of plasma membrane; easy-to-modify structure; and low chance of genetic recombination in treated cells. Herein, we introduce small molecules that induce the neuroectodermal differentiation of mouse embryonic stem cells (ESCs). The small molecules were identified via ESC-based consecutive screenings of small-molecule libraries composed of 324 natural compounds or 93 selected drugs. The natural compounds discovered in the first screening were used to select 93 structurally similar drugs out of 1,200 approved drugs. In the second screening, among the 93 compounds, we found 4 drugs that induced the neuroectodermal differentiation of ESCs. These drugs were progesteroneor corticoid-derivatives. Our results suggest that small molecules targeting the progesterone receptor or glucocorticoid receptor could be used as chemical tools to induce the differentiation of PSCs into a specific germ lineage.

• YAKHAK HOEJI
• /
• v.51 no.6
• /
• pp.476-481
• /
• 2007

A polymorphic fungus, Candida albicans, causes various forms of infections such as disseminated candidiasis and vaginitis. Recent reports indicate that the fungus is a main etiological agent for the arthritis. In search of new sources for treatment of the fungal arthritis, we examined $18{\beta}$-glycyrrhetinic acid ($18{\beta}$-GA) against C. albicans-caused septic arthritis. The compound is isolated from Glycyrrhizae Radix that is known to have various immunomodulating activities and is one of the most popular herbal medicines. For induction of animal model of a septic arthritis, mice were given an emulsion form of C. albicans cell wall mixed with Complete Freund's Adjuvant (CFA) via footpad-injection. To determine prophylactic and therapeutic effects, the component was given to the animals before or after the induction of the arthritis, respectively. Data showed that intraperitoneal administration of $18{\beta}$-GA resulted in reduction of the inflammation, indicating the component had both prophylactic and therapeutic activities. For investigation of mechanism of the $18{\beta}$-GA, inhibitory effects on NO (nitiric oxide) and on T-lymphocyte proliferation were determined. Results demonstrated that $18{\beta}$-GA suppressed NO production from LPS (lipopolysaccharide)-treated macrophages and also inhibited proliferation of Con A (concanavalin A)activated T-cells. Taken together, $18{\beta}$-GA, a pentacyclic triterpene, has anti-arthritic activity against C. albicans-caused septic arthritis, possibly by blocking NO production and T-cell suppression.

• Journal of Microbiology and Biotechnology
• /
• v.32 no.12
• /
• pp.1547-1552
• /
• 2022

β-Amyrin is a pentacyclic triterpene widely distributed in leaves and stems worldwide. The ability of β-amyrin to induce the production of reactive oxygen species (ROS) in microorganisms suggests its potential as an antimicrobial agent. Thus, this study aimed to elucidate the antibacterial mode of action of β-amyrin. We treated Escherichia coli cells with β-amyrin and found that it triggered ROS accumulation. Excessive stress caused by ROS, particularly hydroxyl radicals, induces glutathione (GSH) dysfunction. GSH protects cells from oxidative and osmotic stresses; thus, its dysfunction leads to membrane depolarization. The resultant change in membrane potential leads to the release of apoptotic proteins, such as caspases. The activated caspases-like protein promotes the cleavage of DNA into single strands, which is a hallmark of apoptosis-like death in bacteria. Apoptotic cells usually undergo events such as DNA fragmentation and phosphatidylserine exposure, differentiating them from necrotic cells, and the cells treated with β-amyrin in this study were positive for annexin V and negative for propidium iodide, indicating apoptosis-like death. In conclusion, our findings suggest that the antibacterial mode of action of β-amyrin involves the induction of ROS, which resulted in apoptosis-like death in E. coli.

• Applied Biological Chemistry
• /
• v.49 no.4
• /
• pp.270-275
• /
• 2006

[ $2{\beta},\;3{\alpha}$ ], 23-trihydroxyrus-12-ene-28-oic acid was isolated from Trapa pseudoincisa S. et Z. It has a common structure of pentacyclic triterpenes and belongs to the amyrin ursolic acid group. The cytotoxic effect of this compound was investigated in human hepatoma cell line HepG2. $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid showed dose-dependent cytotoxicity in HepG2 cells. Confocal microscopy data showed that green fluorescence was increased in $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid treated-HepG2 cells in a time-dependent manner. $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid also increased the sub-G1 cell population of HepG2 cells as well as ladder-like DNA fragmentation. Taken together, our results indicate that $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid induced apoptosis in HepG2 cells.

• Journal of Food Hygiene and Safety
• /
• v.30 no.1
• /
• pp.98-102
• /
• 2015

Oleanolic acid and its derivatives are pentacyclic triterpene acids, which are produced in many plants and herbs. These are considered safe and thus, oleanolic acid is now used for cosmetic and pharmaceutical industry. Oleanolic acid affects peptidoglycan in cell wall of bacteria. Hence, the antimicrobial activity of oleanolic acid is not very obvious to Gram-negative bacteria such as Escherichia coli, Yersinia enterocolitica, Shigella flexneri, and Shigella sonnei because the peptidoglycan is covered with outer membrane. However, oleanolic acid derivatives showed improved antimicrobial activity to Gram-negative bacteria. For Gram-positive bacteria such as Staphylococcus aureus and Listeria monocytogenes, oleanolic acid was very effective on reducing the cell counts of the pathogens. In addition, the cytotoxicity of oleanolic acid for human cell lines was minimal. Therefore, oleanolic acid should be considered as an antimicrobial food additive and a therapeutic agent to control foodborne pathogens.

• Biomolecules & Therapeutics
• /
• v.25 no.6
• /
• pp.618-624
• /
• 2017

Betulinic acid (BA), a natural pentacyclic triterpene found in many medicinal plants is known to have various biological activity including tumor suppression and anti-inflammatory effects. In this study, the cell-death induction effect of BA was investigated in BV-2 microglia cells. BA was cytotoxic to BV-2 cells with $IC_{50}$ of approximately $2.0{\mu}M$. Treatment of BA resulted in a dose-dependent chromosomal DNA degradation, suggesting that these cells underwent apoptosis. Flow cytometric analysis further confirmed that BA-treated BV-2 cells showed hypodiploid DNA content. BA treatment triggered apoptosis by decreasing Bcl-2 levels, activation of capase-3 protease and cleavage of PARP. In addition, BA treatment induced the accumulation of p62 and the increase in conversion of LC3-I to LC3-II, which are important autophagic flux monitoring markers. The increase in LC3-II indicates that BA treatment induced autophagosome formation, however, accumulation of p62 represents that the downstream autophagy pathway is blocked. It is demonstrated that BA induced cell death of BV-2 cells by inducing apoptosis and inhibiting autophagic flux. These data may provide important new information towards understanding the mechanisms by which BA induce cell death in microglia BV-2 cells.

• Animal cells and systems
• /
• v.1 no.1
• /
• pp.151-155
• /
• 1997

Promoter of the Drosophila proliferating cell nuclear antigen (PCNA) gene contains DRE (Drosophila DNA replication-related element) required for the high level expression of replication-related genes. Recently, we found that promoter region of the D-raf (a Drosophila homolog of the human c-raf-1) contains two sequences homologous to the DRE and demonstrated the DRE/DREF (DRE-binding factor) involvement in regulation of the D-raf gene. In this study, using ursolic acid (UA), a pentacyclic triterpene acid reported to possess antitumor activities, we examined effects of UA on proliferation of the Drosophila cultured Kc cells and on expression of the PCNA and D-raf genes. UA showed an inhibitory effect on proliferation of the Kc cells in a concentration-dependent manner in DNA content assays and [3H]thymidine incorporation assays. The IC50 value of anti-proliferative effects of UA in DNA content assays was about 7.5uM. UA showed inhibitory effects on expression of the PCNA as well as on that of the D-raf, which were examined with the reporter plasmic p5'-168DPCNACAT or p5'-878DrafCAT, respectively. The results obtained in the present study suggest that expression of the PCNA and D-raf genes is coordinately regulated in at least UA-treated Kc cells and that down-regulation of expression of the PCNA and D-raf genes might be related with the antitumor activities of UA.

• Archives of Pharmacal Research
• /
• v.26 no.12
• /
• pp.1087-1095
• /
• 2003

Betulinic acid (BA), a pentacyclic triterpene isolated from Lycopus lucidus, has been reported to be a selective inducer of apoptosis in various human cancer and shown anti-inflammatory and immunomodulatory properties. We postulated that BA modulates the immunomodulatory properties at least two groups of protein mediators of inflammation, interlukin-1$\beta$ (IL-1$\beta$) and the tumor necrosis factor- $\alpha$ (TNF-$\alpha$) on the basis of the critical role of the monocytes and tissue macrophages in inflammatory and immune responses. TNF-$\alpha$ and IL-1$\beta$ were produced by BA in a dose dependent manner at concentration of 0.625 and 10 $\mu$g/mL. The production of NO associated with iNOS was inhibited when treated with LPS at the concentration of 2.5 to 20 $\mu$g/mL of BA whereas COX-2 expression was decreased at 2.5 to 20 $\mu$g/mL. These modulations of inflammatory mediators were examined in LPS-stimulated RAW 264.7 cells and peritoneal macrophages. The morphology of macrophage was also examined and enhanced surface CD 40 molecule was expressed when treated BA at 0.625∼5 $\mu$g/mL with or without LPS. Furthermore, BA (20 $\mu$g/mL) enhanced apoptosis by producing DNA ladder in the RAW 264.7 cells. Our results indicated that BA induced activation of macrophage and pro-inflammatory cytokines. This may provide a molecular basis for the ability of BA to mediate macrophage, suppress inflammation, and modulate the immune response.