Sung-Ju Lee

Dr. Sung-Ju Lee


Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

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

Representative Publications

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15 September 2023 in Nutrients
Verified
Journal Article
Open access
PDF file
SLSung-Ju Lee
Sung-Ju Lee
SJSeon-A Jang
Seon-A Jang
SKSeong Cheol Kim
Seong Cheol Kim
DGDong Ryun Gu
Dong Ryun Gu
HYHyun Yang
Hyun Yang
HHHyunil Ha
Hyunil Ha
Euonymus alatus (Thunb.) Siebold, a traditional medicinal plant, has been used in China and several other Asian countries to address a variety of health concerns. The extensive research conducted on E. alatus is driven by its diverse pharmacological applications. However, its biological effects on osteoclastogenesis and osteoporosis have not been previously studied. In this research, we investigated the impact of an ethanolic extract of E. alatus (EEEA) on osteoclast differentiation and function as well as estrogen deficiency-induced bone loss. We found that EEEA inhibits osteoclast differentiation by downregulating the expression of the receptor activator of nuclear factor-κB ligand (RANKL) in osteoclast-supporting cells and by directly impeding RANKL-mediated signaling pathways for osteoclastogenesis in precursor cells. In addition, EEEA inhibited the bone-resorptive function of mature osteoclasts in vitro. Furthermore, oral administration of EEEA significantly alleviated bone loss in an ovariectomy-induced osteoporosis mouse model. Additionally, we identified phytochemicals in EEEA that have suppressive effects on osteoclast differentiation and bone loss. Collectively, these results suggest that EEEA holds potential as a biotherapeutic candidate for anti-postmenopausal osteoporosis.

Verified
Journal Article
Open access
PDF file
SLSung-Ju Lee
Sung-Ju Lee
SJSeon-A Jang
Seon-A Jang
SKSeong Cheol Kim
Seong Cheol Kim
JRJin Ah Ryuk
Jin Ah Ryuk
HHHyunil Ha
Hyunil Ha
Lophatherum gracile Bronghiart, used in traditional herbal medicine, has many biological properties including antiviral, antipyretic, antitumor, vasorelaxation, and neutrophilic inflammatory effects. However, its modulatory effects on bone metabolism have not been investigated previously. In this study, we examined the effects of a water extract of the leaves of L. gracile (WELG) on osteoclast differentiation and bone loss, and explored its underlying mechanisms. We found that WELG inhibits osteoclastogenesis by suppressing both receptor activator of nuclear factor-κB ligand (RANKL)-induced early activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB)- and RANKL-induced modulation of the positive and negative regulators of osteoclastogenesis in osteoclast precursors. In vivo study demonstrated that WELG protects against bone loss, weight gain, and fat accumulation without affecting uterine atrophy in an ovariectomy-induced postmenopausal osteoporosis mice model. In addition, photochemical analysis of WELG identified active constituents known to have bone-protective effects. Overall, the results of this study suggest that WELG can be a potential candidate for therapy and prevention of postmenopausal osteoporosis.

Verified
Journal Article
Open access
PDF file
SLSung-Ju Lee
Sung-Ju Lee
HYHyun Yang
Hyun Yang
SKSeong Cheol Kim
Seong Cheol Kim
DGDong Ryun Gu
Dong Ryun Gu
JRJin Ah Ryuk
Jin Ah Ryuk
HHHyunil Ha
Hyunil Ha
Radix Asteris, the root of Aster tataricus L. f., is historically significant in East Asian medicine for treating respiratory conditions. Yet, its implications on bone health remain uncharted. This research investigated the impact of an aqueous ethanol extract of Radix Asteris (EERA) on osteoclast differentiation and its prospective contribution to osteoporosis management. We discerned that EERA retards osteoclast differentiation by inhibiting receptor activator of nuclear factor kappa-B ligand (RANKL) expression and obstructing RANKL-induced osteoclastogenesis. EERA markedly suppressed RANKL-induced expression of NFATc1, a pivotal osteoclastogenic factor, via modulating early RANK signaling. EERA’s therapeutic potential was underscored by its defense against trabecular bone degradation and its counteraction to increased body and perigonadal fat in ovariectomized mice, mirroring postmenopausal physiological changes. In the phytochemical analysis of EERA, we identified several constituents recognized for their roles in regulating bone and fat metabolism. Collectively, our findings emphasize the potential of EERA in osteoclast differentiation modulation and in the management of osteoporosis and associated metabolic changes following estrogen depletion, suggesting its suitability as an alternative therapeutic strategy for postmenopausal osteoporosis intertwined with metabolic imbalances.

29 November 2024 in Cells
Verified
Journal Article
Open access
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KKkyung-yun kang
kyung-yun kang
Sonny RamosSonny Ramos
Sonny Ramos
SLSung-Ju Lee
Sung-Ju Lee
Sang-Jip NamSang-Jip Nam
Sang-Jip Nam
JKJong-Jin Kim
Jong-Jin Kim
Inducing programmed cell death in tumors is a fundamental approach in cancer therapy, prompting extensive efforts to discover bioactive compounds with anticancer properties. Peucedanum japonicum, a plant used in traditional medicine across East Asia, has been reported to exhibit various biological activities, including anticancer effects. This study aimed to evaluate the apoptosis-inducing effects of methanol/dichloromethane (MeOH/CH2Cl2) extracts of P. japonicum roots and their components in HL-60 human leukemia cells. Compounds were isolated using solvent extraction and reverse-phase column chromatography, and their structures were confirmed by nuclear magnetic resonance (NMR) spectroscopy. The cytotoxicity effect of the compounds was tested on various cancer cell lines (HL-60, A549, and MCF-7). Two coumarins, (−)-isosamidin (1) and 3′S,4′S-disenecioylkhellactone (2), were isolated through bioactivity-guided fractionation. Compound 2 significantly induced apoptosis in HL-60 cells, as evidenced by an increase in the sub-G1 cell population and the initiation of both early and late apoptosis. Additional apoptotic markers, including reduced mitochondrial membrane potential (MMP) and increased cleavage of caspase-3, -8, and -9, were observed. These findings suggest that compound 2 shows potential as a candidate for leukemia treatment, providing a promising natural-product-based approach to cancer therapy.

9 October 2023 in Nutrients
Verified
Journal Article
Open access
PDF file
SJSeon-A Jang
Seon-A Jang
SLSung-Ju Lee
Sung-Ju Lee
YHYoun-Hwan Hwang
Youn-Hwan Hwang
HHHyunil Ha
Hyunil Ha
Anethum graveolens L., known as European dill, is a versatile herb widely used in both traditional medicine and culinary practices. Despite its long-standing history, the potential impact of the water extract of A. graveolens seeds (WEAG) on bone health remains unexplored. In this study, we investigated the influence of WEAG on osteoclast differentiation and assessed its potential as an anti-osteoporotic agent. WEAG hindered osteoclast differentiation through the suppression of receptor activator of nuclear factor-κB ligand (RANKL) expression in osteoclast-supporting cells and by directly targeting osteoclast precursor cells. WEAG significantly reduced the expression of key osteoclastogenic transcription factors, namely c-Fos and NFATc1, typically induced by RANKL in osteoclast precursors. This reduction was attributed to the suppression of both MAPKs and NF-κB pathways in response to RANKL. In vivo experiments further revealed that WEAG administration effectively reduces trabecular bone loss and weight gain triggered by ovariectomy, mimicking postmenopausal osteoporosis. Furthermore, our comprehensive phytochemical analysis of WEAG identified a range of phytochemical constituents, associated with bone health and weight regulation. Notably, we discovered a specific compound, isorhamnetin-3-O-glucuronide, within WEAG that exhibits anti-osteoclastogenic potential. Overall, this research elucidated the beneficial effects and mechanistic basis of WEAG on osteoclast differentiation and bone loss, indicating its potential as a viable alternative to address bone loss in conditions like postmenopause.

Verified
Journal Article
Open access
PDF file
DGDong Ryun Gu
Dong Ryun Gu
HYHyun Yang
Hyun Yang
SKSeong Cheol Kim
Seong Cheol Kim
SLSung-Ju Lee
Sung-Ju Lee
HHHyunil Ha
Hyunil Ha
Pulsatilla koreana Nakai (P. koreana) is a perennial herb traditionally used to treat malaria and fever. Although the pharmacological properties of P. koreana have been explored in various contexts, its effects on bone diseases, such as osteoporosis, remain poorly studied. In this study, we investigated the effects of water extracts of P. koreana (WEPK) on osteoclasts, which play a crucial role in bone remodeling, and an ovariectomized (OVX) mouse model, which mimics osteoporosis. Phytochemical profiling of WEPK revealed several compounds that regulate bone or fat metabolism. WEPK suppressed osteoclast differentiation by downregulating the expression of receptor activator of nuclear factor-κB ligand (RANKL), a cytokine that induces osteoclastogenesis. Additionally, WEPK directly inhibited RANKL-induced differentiation of osteoclast precursors by downregulating nuclear factor of activated T cells 1 (NFATc1), the master transcription factor for osteoclastogenesis, by modulating its upstream regulators. In vivo, oral administration of WEPK suppressed bone loss, reduced weight gain, and mitigated fat accumulation in the liver and gonadal tissues of OVX mice. Given its positive impact on bone and fat accumulation under estrogen deficiency, WEPK may serve as a promising alternative therapy for postmenopausal osteoporosis, especially when accompanied by other metabolic disorders, such as obesity and fatty liver.