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5. Toll‐like receptor 13‐mediated signaling protects against the development of colon cancer.

Author

Rafique, Asma, Ali, Irshad, Kim, Seukchan, Farooq, Adeel, Manzoor, Umar, Moon, Jeungho, Arooj, Madeeha, Ahn, Meejung, Park, Youngjun, Hyun, Chang Lim, and Koh, Young‐Sang

Subjects
INTESTINAL barrier function, COLON cancer, INTESTINAL diseases, INTESTINAL cancer, ULCERATIVE colitis
Abstract

Appropriate host‐microbiota interactions are essential for maintaining intestinal homeostasis; hence, an imbalance in these interactions leads to inflammation‐associated intestinal diseases. Toll‐like receptors (TLRs) recognize microbial ligands and play a key role in host–microbe interactions in health and disease. TLR13 has a well‐established function in enhancing host defenses against pathogenic bacteria. However, its role in maintaining intestinal homeostasis and controlling colitis‐associated colon cancer (CAC) is largely unknown. This study aimed to investigate the involvement of TLR13‐mediated signaling in intestinal homeostasis and colonic tumorigenesis using ex vivo cell and in vivo CAC animal model. Tlr13‐deficient mice were prone to dextran sodium sulfate (DSS)‐induced colitis. During the early stages of the CAC regimen (AOM/DSS‐treated), Tlr13 deficiency led to severe ulcerative colitis. Moreover, Tlr13‐deficient mice exhibited increased intestinal permeability, as evidenced by elevated levels of fluorescein isothiocyanate (FITC)‐dextran, endotoxins, and bacterial translocation. Enhanced cell survival and proliferation of colonic intestinal cells were observed in Tlr13‐deficient mice. A transcriptome analysis revealed that Tlr13 deficiency is associated with substantial changes in gene expression profile of colonic tumor tissue. Tlr13‐deficient mice were more susceptible to CAC, with increased production of interleukin (IL)‐6, IL‐12, and TNF‐α cytokines and enhanced STAT3, NF‐κB, and MAPK signaling in colon tissues. These findings suggest that TLR13 plays a protective role in maintaining intestinal homeostasis and controlling CAC. Our study provides a novel perspective on intestinal health via TLR13‐mediated signaling, which is crucial for deciphering the role of host‐microbiota interactions in health and disease. [ABSTRACT FROM AUTHOR]

Published
2024
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6. Chemical Composition, Antioxidant, and Anti-Inflammatory Properties of the Extracts of Hormophysa triquetra and Padina gymnospora.

Author

Osman, Nehal A.H.K., Arooj, Madeeha, Kang, Hee-Kyoung, Hyun, Jin Won, and Koh, Young-Sang

Subjects
HIGH performance liquid chromatography, GAS chromatography/Mass spectrometry (GC-MS), FATTY acid derivatives, CINNAMIC acid, DENDRITIC cells
Abstract

Introduction: Hormophysa triquetra and Padina gymnospora are widely distributed seaweeds in subtropical and tropical seas; however, there are limited or no reports on their biomedical applications. The aim of this study was to investigate the chemical composition of these species and present their antioxidant and anti-inflammatory properties. Methods: The total phenolic content in an 80% methanol extract of the species was measured. High-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) were used to assess the components of the extracts. Antioxidant activity against AAPH- or H2O2-induced oxidative stress in Vero cells was measured using the MTT assay. For anti-inflammatory assessment, the Griess assay was used to measure nitric oxide (NO) production in LPS-stimulated RAW264.7 cells, and enzyme linked immunosorbent assay was employed to measure the inhibition of cytokine production in LPS-stimulated bone marrow-derived dendritic cells. Results: Both seaweed species exhibited significant phenolic content. HPLC profiles revealed 19 compounds, with cinnamic acid (29.63 µg/g) and pyrogallol (25.33 µg/g) dominating in Hormophysa triquetra and Padina gymnospora, respectively. GC-MS profiles were dominant for fatty acids and their derivatives, along with diterpenes. The extracts exhibited protective effects against oxidative stress. Furthermore, the extracts inhibited the production of NO and cytokines in a dose-dependent manner. Conclusion: These findings highlight the therapeutic potential of the species against oxidative stress and inflammation, suggesting their applicability in the pharmaceutical and nutraceutical industries. [ABSTRACT FROM AUTHOR]

Published
2024
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7. Secobutanolides Isolated from Lindera obtusiloba Stem and Their Anti-Inflammatory Activity.

Author

Yang, Hye Jin, Koh, Young-Sang, Na, MinKyun, and Li, Wei

Subjects
*DENDRITIC cells, *ANTI-inflammatory agents, *CHEMICAL structure, *LIPOPOLYSACCHARIDES, *DATA analysis
Abstract

In this study, a new secobutanolide, named secosubamolide B (3), along with three previously known secobutanolides (1, 2, and 4), were successfully isolated from a methanol extract of the stem of Lindera obtusiloba. The chemical structures of these compounds were elucidated through the analysis of spectroscopic data, and then compared with the existing literature to confirm their identities. Furthermore, the anti-inflammatory effect of these isolated compounds on bone marrow-derived dendritic cells stimulated by lipopolysaccharide (LPS) was evaluated. Compounds 1–3 showed the significant suppression of LPS-triggered IL-6 and IL-12 p40 production, with IC50 values between 1.8 and 24.1 µM. These findings may provide a scientific foundation for developing anti-inflammatory agents from L. obtusiloba. [ABSTRACT FROM AUTHOR]

Published
2024
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8. The inhibitory effect of chlorogenic acid on oxidative stress and apoptosis induced by PM2.5 in HaCaT keratinocytes.

Author

Herath, Herath Mudiyanselage Udari Lakmini, Piao, Mei Jing, Kang, Kyoung Ah, Fernando, Pincha Devage Sameera Madushan, Kang, Hee Kyoung, Koh, Young Sang, and Hyun, Jin Won

Subjects
PARTICULATE matter, CHLOROGENIC acid, PROTEIN kinase inhibitors, REACTIVE oxygen species, CYTOCHROME c
Abstract

Exposure to fine particulate matter with an aerodynamic diameter of less than 2.5 μm (PM2.5) can cause oxidative damage and apoptosis in the human skin. Chlorogenic acid (CGA) is a bioactive polyphenolic compound with antioxidant, antifungal, and antiviral properties. The objective of this study was to identify the ameliorating impact of CGA that might protect human HaCaT cells against PM2.5. CGA significantly scavenged the reactive oxygen species (ROS) generated by PM2.5, attenuated oxidative cellular/organelle damage, mitochondrial membrane depolarization, and suppressed cytochrome c release into the cytosol. The application of CGA led to a reduction in the expression levels of Bcl‐2‐associated X protein, caspase‐9, and caspase‐3, while simultaneously increasing the expression of B‐cell lymphoma 2. In addition, CGA was able to reverse the decrease in cell viability caused by PM2.5 via the inhibition of extracellular signal‐regulated kinase (ERK). This effect was further confirmed by the use of the mitogen‐activated protein kinase kinase inhibitor, which acted upstream of ERK. In conclusion, CGA protected keratinocytes from mitochondrial damage and apoptosis via ameliorating PM2.5‐induced oxidative stress and ERK activation. [ABSTRACT FROM AUTHOR]

Published
2024
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32. 5-Bromo-3,4-dihydroxybenzaldehyde Promotes Hair Growth through Activation of Wnt/β-Catenin and Autophagy Pathways and Inhibition of TGF-β Pathways in Dermal Papilla Cells

Author

Kang, Jung-Il, primary, Choi, Youn Kyung, additional, Han, Sang-Chul, additional, Nam, Hyunwoo, additional, Lee, Gilwoo, additional, Kang, Ji-Hoon, additional, Koh, Young Sang, additional, Hyun, Jin Won, additional, Yoo, Eun-Sook, additional, and Kang, Hee-Kyoung, additional

Published
2022
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