Jiyoung You

Ms. Jiyoung You


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

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

Representative Publications

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22 September 2015 in Molecules
Verified
Journal Article
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JYJiyoung You
Jiyoung You
KRKyung-Baeg Roh
Kyung-Baeg Roh
ZLZidan Li
Zidan Li
LGLiu Guangrong
Liu Guangrong
JTJian Tang
Jian Tang
EJEunsun Jung
Eunsun Jung
Andrographis paniculata (A. paniculata, Chuanxinlian), a medicinal herb with an extremely bitter taste that is native to China and other parts of Southeast Asia, possesses immense therapeutic value; however, its therapeutic properties have rarely been applied in the field of skin care. In this study, we investigated the effect of an A. paniculata extract (APE) on human epidermal stem cells (EpSCs), and confirmed its anti-aging effect through in vitro, ex vivo, and in vivo study. An MTT assay was used to determine cell proliferation. A flow cytometric analysis, with propidium iodide, was used to evaluate the cell cycle. The expression of integrin β1 (CD29), the stem cell marker, was detected with antibodies, using flow cytometry in vitro, and immunohistochemical assays in ex vivo. Type 1 collagen and VEGF (vascular endothelial growth factor) were measured using an enzyme-linked immunosorbent assay (ELISA). During the clinical study, skin hydration, elasticity, wrinkling, sagging, and dermal density were evaluated before treatment and at four and eight weeks after the treatment with the test product (containing the APE) on the face. The proliferation of the EpSCs, treated with the APE, increased significantly. In the cell cycle analysis, the APE increased the G2/M and S stages in a dose-dependent manner. The expression of integrin β1, which is related to epidermal progenitor cell expansion, was up-regulated in the APE-treated EpSCs and skin explants. In addition, the production of VEGF in the EpSCs increased significantly in response to the APE treatment. Consistent with these results, the VEGF and APE-treated EpSCs conditioned medium enhanced the Type 1 collagen production in normal human fibroblasts (NHFs). In the clinical study, the APE improved skin hydration, dermal density, wrinkling, and sagging significantly. Our findings revealed that the APE promotes a proliferation of EpSCs, through the up-regulation of the integrin β1 and VEGF expression. The VEGF might affect the collagen synthesis of NHF as a paracrine factor. Clinical studies further suggested that treatment with formulations containing APE confers anti-aging benefits. Based on these results, we suggest that APE may be introduced as a possible anti-aging agent.

Verified
Journal Article
Open access
PDF file
JYJiyoung You
Jiyoung You
YJYoungsu jang
Youngsu jang
JSJunbo Sim
Junbo Sim
DRDehun Ryu
Dehun Ryu
ECEunae Cho
Eunae Cho
EJEunsun Jung
Eunsun Jung
The activation of hair follicle dermal papilla cells (HFDPCs), a critical target of hair loss relief, can be achieved through the upregulation of proliferation, the stimulation of hair inducibility, and the inhibition of cellular senescence. Veratric acid (VA) is a major benzoic acid found in fruits and vegetables. The biological activity of VA on HFDPCs remains to be elucidated. In this study, we investigated the capacity of VA for hair loss mitigation. An MTT assay, Ki67 staining, quantitative RT-PCR (qRT-PCR), and a Western blot analysis were performed to confirm the proliferative effect of VA. Hair inductivity was determined through a cell aggregation assay and ALP staining. Annexin V/PI staining was performed to confirm the anti-apoptotic effect of VA. The inhibitory effect of VA on cellular senescence was confirmed by a β-galactosidase (β-gal) assay and qRT-PCR using replicative senescence and oxidative stress-induced senescence models. As a result, VA dose-dependently upregulated the proliferation of HFDPCs, the expression of growth factors, and β-catenin protein levels. VA also dose-dependently increased ALP activity and cell aggregation and decreased apoptotic cells through the regulation of BCL2 and BAX expression. Moreover, VA reduced β-gal activity and the senescence-associated secretory phenotype (SASP) in a dose-dependent manner in senescent HFDPCs. These findings suggest that VA may serve as a potential therapeutic agent for alleviating hair loss by targeting multiple pathways involved in HFDPC activation.