• Journal of Ginseng Research
• /
• v.47 no.2
• /
• pp.337-346
• /
• 2023

Background: Ginsenoside Rb2, a major active component of Panax ginseng, has various physiological activities, including anticancer and anti-inflammatory effects. However, the mechanisms underlying the rejuvenation effect of Rb2 in human skin cells have not been elucidated. Methods: We performed a senescence-associated β-galactosidase staining assay to confirm cellular senescence in human dermal fibroblasts (HDFs). The regulatory effects of Rb2 on autophagy were evaluated by analyzing the expression of autophagy marker proteins, such as microtubule-associated protein 1A/1B-light chain (LC) 3 and p62, using immunoblotting. Autophagosome and autolysosome formation was monitored using transmission electron microscopy. Autophagic flux was analyzed using tandem-labeled GFP-RFP-LC3, and lysosomal function was assessed with Lysotracker. We performed RNA sequencing to identify potential target genes related to HDF rejuvenation mediated by Rb2. To verify the functions of the target genes, we silenced them using shRNAs. Results: Rb2 decreased β-galactosidase activity and altered the expression of cell cycle regulatory proteins in senescent HDFs. Rb2 markedly induced the conversion of LC3-I to LC3-II and LC3 puncta. Moreover, Rb2 increased lysosomal function and red puncta in tandem-labeled GFP-RFP-LC3, which indicate that Rb2 promoted autophagic flux. RNA sequencing data showed that the expression of DNA damage-regulated autophagy modulator 2 (DRAM2) was induced by Rb2. In autophagy signaling, Rb2 activated the AMPK-ULK1 pathway and inactivated mTOR. DRAM2 knockdown inhibited autophagy and Rb2-restored cellular senescence. Conclusion: Rb2 reverses cellular senescence by activating autophagy via the AMPK-mTOR pathway and induction of DRAM2, suggesting that Rb2 might have potential value as an antiaging agent.

• Journal of Life Science
• /
• v.33 no.1
• /
• pp.73-81
• /
• 2023

In the present study, we prepared hot water extracts and the subsequent organic solvent fractions of methanol extracts of Houttuynia cordata (HC) and Lespedeza cuneata (LC), and investigated their anti-inflammatory effects on lipopolysaccharide-stimulated RAW264.7 cells. Among the treated samples, hexane, chloroform, and ethyl-acetate fractions of HC and LC inhibited nitric oxide (NO) production in a dose-dependent manner, and decreased inducible nitric oxide synthase (iNOS) protein expression. And, we analyzed the flavonoid contents of the ethyl-acetate fraction of HC and LC, and chose apigenin for the further experiments because apigenin was one of flavonoids commonly found in HC and LC. Apigenin dramatically inhibited NO production in a dose-dependent manner without affecting cell viability and decreased iNOS and cyclooxygenase-2 (COX-2) expression. In addition, apigenin suppressed the phosphorylation of p38 and Jun N-terminal kinase (JNK) indicating that apigenin exerts anti-inflammatory activity via the mitogen-activated protein kinase (MAPK) signaling pathway. Subsequently, we conducted RNA-sequencing analysis to detect differentially expressed genes upon apigenin treatment. Among the down-regulated genes, four cytokine genes (interleukin (IL)-1α, IL-1β, IL-6, and colony stimulating factor 2 (CSF2)) were selected for the further analysis, and the reduction of their expression by apigenin was confirmed with quantitative real-time polymerase chain reaction. Overall, our results suggest that Houttuynia cordata and Lespedeza cuneata have the anti-inflammatory effects and apigenin can be the one of key molecules responsible for their anti-inflammatory activities.

• Molecules and Cells
• /
• v.45 no.12
• /
• pp.886-895
• /
• 2022

Malignant rhabdoid tumor (MRT) is a highly aggressive pediatric malignancy with no effective therapy. Therefore, it is necessary to identify a target for the development of novel molecule-targeting therapeutic agents. In this study, we report the importance of the runt-related transcription factor 1 (RUNX1) and RUNX1-Baculoviral IAP (inhibitor of apoptosis) Repeat-Containing 5 (BIRC5/survivin) axis in the proliferation of MRT cells, as it can be used as an ideal target for anti-tumor strategies. The mechanism of this reaction can be explained by the interaction of RUNX1 with the RUNX1-binding DNA sequence located in the survivin promoter and its positive regulation. Specific knockdown of RUNX1 led to decreased expression of survivin, which subsequently suppressed the proliferation of MRT cells in vitro and in vivo. We also found that our novel RUNX inhibitor, Chb-M, which switches off RUNX1 using alkylating agent-conjugated pyrrole-imidazole polyamides designed to specifically bind to consensus RUNX-binding sequences (5'-TGTGGT-3'), inhibited survivin expression in vivo. Taken together, we identified a novel interaction between RUNX1 and survivin in MRT. Therefore the negative regulation of RUNX1 activity may be a novel strategy for MRT treatment.

• Journal of Korean society of Dental Hygiene
• /
• v.23 no.4
• /
• pp.219-226
• /
• 2023

Objectives: This study aimed to investigate the effects of rhubarb extract on osteoclast differentiation in bone marrow-derived macrophages (BMMs). Osteoclasts are vital for bone resorption and remodeling. Osteoclast dysregulation can contribute to various bone-related disorders that directly affect oral health. Rhubarb, a medicinal plant with anti-inflammatory properties, has been shown to modulate bone metabolism. Methods: BMMs were isolated from the femurs and tibias of 5-week-old C57BL/6 mice and cultured in the presence of mouse macrophage colony-stimulating factor (M-CSF) for 3 days. Subsequently, BMMs were treated with M-CSF and receptor activator of nuclear factor-κB ligand (RANKL) to induce osteoclast differentiation. Results: Rhubarb extract effectively suppressed osteoclast differentiation in BMMs. Furthermore, rhubarb extract inhibited the mRNA expression of tartrate-resistant acid phosphatase (TRAP) and cathepsin K (CTSK), which are essential for osteoclastogenesis. Moreover, it inhibited the RANKL-induced expression of nuclear factor of activated T cell c1 (NFATc1), a crucial transcription factor in osteoclast differentiation. Conclusions: These results suggest that rhubarb extract promotes oral health by inhibiting osteoclastogenesis in BMMs. Thus, rhubarb extract shows promise as a therapeutic agent for bone-related disorders that directly affect oral health, particularly those associated with abnormal osteoclast activity. Further research and exploration of the underlying mechanisms are warranted to fully understand their potential clinical applications.

• Journal of Life Science
• /
• v.33 no.5
• /
• pp.445-454
• /
• 2023

Hair graying is the result of a malfunction in the signaling pathways that control melanogenesis, and it is activated by UV light, melanocyte-stimulating hormone (MSH), stem cell factor (SCF), Wnt, and endothelin-1 (ET-1). To prevent hair graying, synthetic and natural compounds can be used to stimulate melanogenesis effectively under the control of tyrosinase, tyrosine hydroxylase, tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF). This article describes a crucial strategy to resolve the problem of hair graying, as well as recent advances in the signaling pathway related to melanogenesis and hair graying. In particular, the article reviews potentially effective therapeutic agents that promote melanogenesis, such as antioxidants that modulate catalase, methionine sulfoxide reductase, and sirtuin 1 (SIRT1) activators including resveratrol, fisetin, quercetin, and ginsenoside. It also discusses vitiligo inhibitors, such as corticosteroids, calcineurin inhibitors, and palmitic acid methyl ester, as well as activators of telomerase expression and activity, including estrogen, androgen, progesterone, and dihydrotestosterone. Furthermore, it explores compounds that can inhibit hair graying, such as latanoprost, erlotinib, imatinib, tamoxifen, and levodopa. In conclusion, this article focuses on recent research trends on compounds that promote melanin production related to hair graying.

• Journal of Life Science
• /
• v.32 no.3
• /
• pp.256-262
• /
• 2022

Oxysterols are oxygenated metabolites of cholesterol generated by serial enzymatic reactions during bile acid synthesis. Similar to cholesterol, oxysterols move rapidly to the intracellular region and modulate various cellular processes, such as immune cell responses, lipid metabolism, and cholesterol homeostasis. Different nuclear transcription factors, such as glucocorticoid, estrogen, and liver X receptors, can be modulated by oxysterols in multiple tissues. The most abundant oxysterol, 27-hydroxycholesterol (27-OHC), is a well-known selective modulator that can either activate or suppress estrogen receptor activity in a tissue-specific manner. The contribution of 27-OHC in atherosclerosis development is apparent because a large amount of it is found in atherosclerotic plaques, accelerating the transformation of macrophages into foam cells that uptake extracellular modified lipids. According to previous studies, however, there are opposing opinions about how 27-OHC affects lipid and cholesterol metabolism in metabolic organs, including the liver and adipose tissue. In particular, the effects of 27-OHC on lipid metabolism are entirely different between in vitro and in vivo conditions, suggesting that understanding the physiology of this oxysterol requires a sophisticated approach. This review summarizes the potential effects of 27-OHC in atherosclerosis and metabolic syndromes with a special discussion of its role in metabolic tissues.

• Journal of Life Science
• /
• v.32 no.3
• /
• pp.210-221
• /
• 2022

This study investigated the mechanisms underlying the anti-cancer effects of non-steroidal anti-inflammatory drugs (NSAIDs) in human cancer cells in combination with either N-[N-(3, 5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT), a γ-secretase inhibitor, or MHY2245, a new synthetic sirtuin 1 inhibitor. The results showed both DAPT and MHY2245 as novel chemosensitizers of human colon cancer KM12 and human hepatocellular carcinoma SNU475 cells to NSAIDs involving celecoxib and 2, 5-dimethyl celecoxib. The NSAID-induced cytotoxicity of these cells was significantly increased by DAPT and MHY2245 in a cyclooxygenase-2 independent manner. In addition, DAPT and MHY2245 reduced levels of p62, Notch1 intracellular domain, and multiple cancer stemness (CS)-related markers including Notch1, CD44, CD133, octamer-binding transcription factor 4, mutated p53 and c-Myc. However, the level of activating transcription factor 4 (ATF4) was enhanced, probably indicating the down-regulation of multiple CS-related markers by DAPT or MHY2245-mediated autophagy induction. Moreover, the NSAID-mediated reduction of p62/nuclear factor erythroid-derived 2-like 2 and CS-related marker proteins and the up-regulation of C/EBP homologous protein (CHOP)/ATF4 were accelerated by DAPT and MHY2245. As such, the combination of NSAID and either DAPT or MHY2245 resulted in higher cytotoxicity than NSAID alone by accelerating the down-regulation of multiple CS-related markers and PARP activation, indicating that both inhibitors promote NSAID-mediated autophagic cell death, possibly through the CHOP/ATF4 pathway. In conclusion, either combination strategy may be useful for the effective treatment of human cancer cells expressing CS-related markers.

• Journal of agriculture & life science
• /
• v.50 no.4
• /
• pp.157-167
• /
• 2016

The changes of total phenolic and isoflavone contents and antioxidant activities in of brown soymilk fermented by Lactobacillus plantarum P1201 were investigated. The brown soymilk proliferated the cell growth and reached about 11.55log cfu/g after fermentation for 60hr, while pH and titratable acidity ranged from 6.25 to 4.03 and 0.18% to 1.03%, respectively. The total phenolic contents of brown soymilk slightly increased from 2.87mg/g to 2.98mg/g after fermentation for 60hr. The levels of isoflavone-glycosides and -malonylglycosides decreased, while the isoflavone-aglycone contents increased during fermentation of brown soymilk. In particular, the isoflavone contents was 38.30㎍/g, but increased the highest value of 84.31㎍/g after fermentation for 60hr. After then, it was slightly decreased after 60hr of fermentation. In addition, the levels of daidzein, glycitein and genistein among isoflavone aglycones were 24.12㎍/g, 25.25㎍/g and 24.71 ㎍/g, after fermentation for 36hr. The DPPH and ABTS radical scavenging activities and FRAP assay showed to be slightly increased during lactic acid fermentation of brown soymilk.

• Journal of Korean Medicine Rehabilitation
• /
• v.33 no.3
• /
• pp.47-65
• /
• 2023

Objectives We evaluated the wound healing effects of Dangguijakyak-san (DJ) using C57BL/6 mice that were generated open wound. Methods The study was conducted with seven C57BL/6 mice assigned to each group, divided into the normal group, control group, vitamin E group, DJ low-dose group, DJ high-dose group. We measured total polyphenol, flavonoid contents, the size of the wound, liver function, pro-inflammatory cytokine activity in serum, inflammation-related proteins, adhesion molecules and chemokine proteins, collagen-related proteins in skin tissue and histopathological changes by H&E and Masson's staining. Results DJ treatment significantly reduced the area of the wound compared to the control group. Also, inflammatory cytokines were reduced and the expression of anti-inflammatory-related factors (interleukin-4 [IL-4] and IL-10) was significantly increased in the DJ treatment group. We identified that DJ treatment inhibits both pathways of inflammation, the mitogen-activated protein kinases and nuclear factor-κB pathway. Moreover, the protein expressions of Sirt1 (sirtuin 1), MCP-1 (monocyte chemoattractant protein 1), ICAM-1 (intercellular adhesion molecule 1), and VCAM-1 (vascular cell adhesion molecule 1) were decreased by DJ administration. Also, the expression of α-smooth muscle actin and collagen type I alpha 1, collagen-related proteins, that help skin recovery was significantly increased in the DJ treatment group. Histopathologically, a relatively thin epithelial layer could be observed in the DJ administration group, as well as an increase in fibroblasts and collagen fibers. Conclusions These data suggest that DJ treatment is effective in wound healing, suppressing inflammatory proteins, increasing skin repair factors and improving histopathological changes caused by wounds.

• Journal of Veterinary Science
• /
• v.24 no.4
• /
• pp.52.1-52.13
• /
• 2023

Background: Mesenchymal stem cells (MSCs) have been investigated as therapeutic agents for inflammatory bowel disease (IBD). Stimulation of MSCs with pro-inflammatory cytokines is an approach to enhance their immunomodulatory effects. However, further investigation is required to support their application in immune-mediated disorders and companion animals. Objectives: This study aimed to assess the therapeutic effect of tumor necrosis factor (TNF)-α-stimulated feline adipose tissue-derived MSCs (fAT-MSCs) in a dextran sulfate sodium (DSS)-induced colitis mouse model. Methods: Colitis mice was made by drinking water with 3% DSS and fAT-MSCs were injected intraperitoneally. Colons were collected on day 10. The severity of the disease was evaluated and compared. Raw 264.7 cells were cultured with the conditioned medium to determine the mechanism, using quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Results: TNF-α-stimulated fAT-MSCs more improved severity of DSS-induced colitis in disease activity, colon length, histologic score, and inflammatory cytokine. In sectionized colon tissues, the group comprising TNF-α-stimulated fAT-MSCs had higher proportion of CD11b⁺CD206⁺ macrophages than in the other groups. In vitro, TNF-α-stimulation increased cyclooxygenase-2 (COX-2) expression and prostaglandin E₂ (PGE₂) secretion from fAT-MSCs. The conditioned medium from TNF-α-stimulated fAT-MSCs enhanced the expression of interleukin-10 and arginase-1 in LPS-activated Raw 264.7 cells. Conclusions: These results represent that TNF-α-stimulated fat-mscs ameliorate the inflamed colon more effectively. Furthermore, we demonstrated that the effectiveness was interlinked with the COX-2/PGE₂ pathway.