Sungho Yun

Prof. Sungho Yun


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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18 August 2018 in Marine Drugs
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YKYoung-In Kim
Young-In Kim
WOWon-Seok Oh
Won-Seok Oh
PSPhil Hyun Song
Phil Hyun Song
SYSungho Yun
Sungho Yun
Young-Sam KwonYoung-Sam Kwon
Young-Sam Kwon
TOTae-Ho OH
Tae-Ho OH
Ultraviolet (UV) B exposure induces DNA damage and production of reactive oxygen species (ROS), which causes skin photoaging through signaling pathways of inflammation and modulation of extracellular matrix remodeling proteins, collagens, and matrix metalloproteinase (MMP). As low molecular-weight fucoidan (LMF) has potential antioxidant and anti-inflammatory properties, we examined the protective effects of LMF against UVB-induced photoaging. A UVB-irradiated mouse model was topically treated with myricetin or LMF at 2.0, 1.0 and 0.2 mg/cm2 (LMF2.0, LMF1.0 and LMF0.2, respectively) once a day for 15 weeks. Wrinkle formation, inflammation, oxidative stress, MMP expression, and apoptosis in the treated regions were compared with those in a distilled water-treated photoaging model (UVB control). LMF treatments, particularly LMF2.0 and LMF1.0, significantly inhibited the wrinkle formation, skin edema, and neutrophil recruitment into the photo-damaged lesions, compared with those in the UVB control. While LMF decreased interleukin (IL)-1β release, it increased IL-10. The LMF treatment inhibited the oxidative stresses (malondialdehyde and superoxide anion) and enhanced endogenous antioxidants (glutathione). Additionally, LMF reduced the mRNA expression of MMP-1, 9, and 13. The histopathological analyses revealed the anti-photoaging effects of LMF exerted via its antioxidant, anti-apoptotic, and MMP-9-inhibiting effects. These suggest that LMF can be used as a skin-protective remedy for photoaging.

28 October 2022 in Animals
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Journal Article
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HKHwan-Deuk Kim
Hwan-Deuk Kim
YKYoung-Jong Kim
Young-Jong Kim
MJMIN JANG
MIN JANG
SBSeul-gi Bae
Seul-gi Bae
SYSungho Yun
Sungho Yun
WLWon-Jae Lee
Won-Jae Lee
The release of reproductive hormones in the hypothalamic–pituitary–gonadal (HPG) axis is regulated by its upstream regulator, kisspeptin, and influenced by external stresses, including heat stress. Since the effect of heat stress (summer infertility) on hypothalamic kisspeptin expression in domestic sows is not yet understood, the present study attempted to identify changes in kisspeptin expression in different seasons (summer and spring). The high atmospheric temperature in summer decreased the pregnancy rate and litter size and increased stress-related hormones as a chronic stressor to domestic sows. The hypothalamic kisspeptin expression in summer was decreased regardless of the estrus phase and negatively correlated with atmospheric temperature, indicating that high temperature decreased kisspeptin. When the activity of hypothalamic kisspeptin neurons in the follicular phase was assessed using c-Fos staining, a decreased number of kisspeptin neurons coexpressing c-Fos was observed in domestic sows in summer. Accordingly, lower expression of kisspeptin induced decreased levels of HPG axis-related reproductive hormones, such as gonadotropins and estrogen, and fewer large ovarian follicles. In conclusion, the present study demonstrated that reduced kisspeptin expression and its neuronal activity in the hypothalamus under heat stress in summer induced downregulation of the HPG axis and caused summer infertility in domestic sows.

1 March 2025 in Animal Bioscience
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TKTae-Gyun Kim
Tae-Gyun Kim
YCYong-ho Choe
Yong-ho Choe
SKSung-Ho Kim
Sung-Ho Kim
SLSang-Yup Lee
Sang-Yup Lee
MJMIN JANG
MIN JANG
WLWon-Jae Lee
Won-Jae Lee
Objective: Pregnancy in cattle after embryo transfer (ET) is influenced by several factors, including embryo quality. Therefore, preparing high-quality embryos with the greatest developmental potential is essential for achieving a successful pregnancy after ET. Meanwhile, blastocysts produced by in vitro fertilization (IVF) procedure have different developmental speed during in vitro culture (IVC) and they exhibited different competence in the establishment of pregnancy.Methods: This study aimed to identify the comparative features of early-, mid-, and late-developing bovine IVF blastocysts, when they first appeared at Day 7, 8, and 9 during IVC, respectively. In addition, the correlations between their molecular features and pregnancy ability were analyzed.Results: The results showed no difference in the morphological characteristics, including total cell count and diameter, between the Day 7, 8, and 9 blastocysts. However, the pregnancy rate post-ET was significantly different between the groups at 51.7%, 36.7%, and 17.8% for Day 7, 8, and 9 blastocysts, respectively. During early embryo development, late-developing blastocysts demonstrated a reduced cell count in the inner cell mass and decreased expression of the early embryo developmental genes (Oct4 and Sox2) compared with the early- and mid-developing blastocysts. In addition, the number of apoptotic cells and apoptosis-related gene expression (increased Bax and decreased Bcl2) gradually elevated from the Day 7 to Day 9 blastocysts. However, there was no difference in mitochondrial activity and mitochondria-relevant gene expression (Tfam and Cox1) between the groups. Correlation analysis identified a significantly negative correlation between the pregnancy rate and the blastocysts’ degree of apoptosis, indicating that the low pregnancy ability of late-developing blastocysts was mainly caused by increased apoptosis.Conclusion: This study’s results may contribute to the field of animal biotechnology by assisting in establishing an improved strategy for bovine ET with IVF embryos.

29 March 2022 in Korean Journal of Veterinary Research
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CMChang-Hwan Moon
Chang-Hwan Moon
DKDae-Hyun Kim
Dae-Hyun Kim
SYSungho Yun
Sungho Yun
HLHaebeom Lee
Haebeom Lee
SJSeong Mok Jeong
Seong Mok Jeong
Canine mammary gland tumors are the most common neoplasms in intact female dogs. Approximately half of all mammary tumors are malignant, and there is a risk of metastasis, which is associated with a poor prognosis. This study is to evaluate the prognostic factors of canine mammary gland tumors and the risk factors associated with the development of malignant tumors. From 2014 to 2020, 60 dogs with mammary gland tumors that underwent surgical treatment were evaluated in this retrospective study. Tumor size, TNM stage, and histopathological results were prognostic factors for 2-year survival after surgery. Every 10 mm increase in tumor size, increased the risk of death within 2 years after surgery 1.213 times. Dogs with TNM stage IV or V had 8.677 fold risk of death within 2 years after surgery. The 2-year survival rate for dogs with benign tumors was 90.2% and for malignant tumors was 67.3%. Tumor size is the most important prognostic factor for canine mammary gland tumors. As tumor size increased by 10 mm, the risk for development of malignant tumors increased by 1.487 times. Tumors larger than 30 mm are highly likely to be malignant, and metastatic evaluation and wide resection should be considered.

Verified
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SBSu-Min Baek
Su-Min Baek
SLSeoung-Woo Lee
Seoung-Woo Lee
TKTae-Un Kim
Tae-Un Kim
SCSeong-Kyoon Choi
Seong-Kyoon Choi
SYSungho Yun
Sungho Yun
Jin-Kyu ParkJin-Kyu Park
Jin-Kyu Park
Senescence marker protein 30 (SMP30) is a cell survival factor playing an important role in vitamin C synthesis and antiapoptosis. Moreover, its cytoprotective role suggests a possibility to be related to cancer cell survival. Mammary carcinoma is a common cancer in both humans and animals. Because of its histopathological diversity, especially in the early stage, histopathological diagnosis may be complicated; therefore, a diagnostic marker is helpful for confirmation. The present study analyzed the expression pattern of SMP30 in mammary carcinoma in humans, dogs, and cats. Immunohistochemistry, immunofluorescence, and western blot analysis were used to investigate SMP30 expression patterns. The expression was specifically observed in neoplastic glandular epithelial cells. The expression increased with the malignancy of glandular epithelial cells with a highly proliferative status. However, SMP30 expression was low in normal mammary gland tissues or well-differentiated adenoma tissues. The patterns were consistently reproduced in canine primary mammary carcinoma cells and MCF-7 and MDA-MB-231 human carcinoma cell lines. This study provides useful information to understand SMP30 expression in various stages of mammary carcinoma and to suggest its utility as a pan-species diagnostic marker, thereby helping to establish strategies for diagnosing mammary carcinoma in several species.

7 February 2021 in Veterinary Sciences
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Min-Soo SeoMin-Soo Seo
Min-Soo Seo
KKKyung-Ku Kang
Kyung-Ku Kang
SOSe-Kyung Oh
Se-Kyung Oh
SSSoo-Eun Sung
Soo-Eun Sung
KKKilSoo Kim
KilSoo Kim
SYSungho Yun
Sungho Yun
Wharton’s jelly is a well-known mesenchymal stem cell source in many species, including humans. However, there have been no reports confirming the presence of mesenchymal stem cells in Wharton’s jelly in cats. The purpose of this study was to isolate mesenchymal stem cells (MSCs) from the Wharton’s jelly of cats and to characterize stem cells. In this study, feline Wharton’s jelly-derived mesenchymal stem cells (fWJ-MSCs) were isolated and successfully cultured. fWJ-MSCs were maintained and the proliferative potential was measured by cumulative population doubling level (CPDL) test, scratch test, and colony forming unit (CFU) test. Stem cell marker, karyotyping and immunophenotyping analysis by flow cytometry showed that fWJ-MSCs possessed characteristic mesenchymal stem cell markers. To confirm the differentiation potential, we performed osteogenic, adipogenic and chondrogenic induction under each differentiation condition. fWJ-MSCs has the ability to differentiate into multiple lineages, including osteogenic, adipogenic and chondrogenic differentiation. This study shows that Wharton’s jelly of cat can be a good source of mesenchymal stem cells. In addition, fWJ-MSCs may be useful for stem cell-based therapeutic applications in feline medicine.