https://scholar.dgist.ac.kr/handle/20.500.11750/11738 2026-05-15T00:57:08Z https://scholar.dgist.ac.kr/handle/20.500.11750/60353 Title: MLPH-mediated activation of dermal papilla IGF-1 signaling drives human hair shaft elongation and anagen induction Author(s): Kwack, Mi Hee; Kang, Eunho; Kim, Jewoo; Ji, Youngheum; Ju, Hyeonchang; Lee, Chang-Hun; Sung, Young Kwan; Kim, So Yeon; Moon, Cheil Abstract: Introduction Hair loss (alopecia) is a multifactorial disorder that often causes distress. Approved therapies such as minoxidil and finasteride act indirectly and do not specifically target hair follicle (HF) cells. Erythropoietin (EPO), however, has been shown to activate dermal papilla (DP) cells via the erythropoietin receptor (EPOR), suggesting a potential role in hair follicle regeneration and hair growth. Objectives This study aimed to develop and validate Helix C-1–based EPO-derived peptides that activate DP cells and increase IGF-1 expression, while not inducing overt systemic erythropoietic effects (e.g., increases in red blood cell counts, reticulocytes, hemoglobin, or hematocrit) under the tested experimental conditions. Methods Peptides derived from the Helix C-1 region of EPO were synthesized and characterized by EPOR-binding affinity, CD spectroscopy, and ERK/AKT activation. In vitro, DP-cell metabolic activity, proliferation, and IGF-1 secretion were assessed. Ex vivo efficacy was evaluated by hair shaft elongation in hair follicle organ culture, and in vivo efficacy was tested in a murine depilation-induced anagen model with concurrent hematologic assessment to exclude erythropoiesis-related effects. Results The peptides increased DP-cell metabolic activity and proliferation, reduced oxidative stress, and enhanced IGF-1 production via EPOR-mediated ERK/AKT activation. They promoted hair shaft elongation ex vivo and promoted anagen entry in mice without significant changes in standard hematologic parameters under the tested dosing regimen. Conclusion These findings support the conclusion that MLPH promotes hair growth via an EPOR-linked, IGF-1–dependent mechanism in DP cells. Future pharmacokinetic and disease-model studies are warranted to evaluate its translational potential. © 2026 The Authors. 2026-02-28T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/60228 Title: Investigation on physical and physiological properties of extracellular vesicles derived from Enterococcus faecalis Author(s): Cho, Jung-Ah; Jeon, Sang Seo; Choi, Go Woon; Lee, Chang-Hun; Kim, Sung-Jae Abstract: Extracellular membrane vesicles (EVs) are nanosized particles that contain various molecules originating from their parental cells and are produced by all three domains of life, including bacteria. Bacterial EVs are known to contribute to bacterial infections and immune responses in various human diseases. Enterococcus faecalis is an opportunistic pathogen. In this study, we examined the physical and physiological properties of EVs generated by E. faecalis, including particle size, protein composition, and cytokine-inducing profiles. To this end, we isolated EVs from bacteria under different preparation processes, and also a certain condition with the addition of EGCG. First, the bacterial culture supernatants were directly ultracentrifuged (named "Rough"), or filtered through 0.45- or 0.22 mu m pore-sized membrane filters (named as "0.45 mu m" or "0.22 mu m," respectively). EVs from EGCG-treated bacteria were prepared using a 0.45 mu m pore-sized membrane filter and named "EGCG + 0.45 mu m." Each EV sample was subjected to DLS, SDS-PAGE, and cytokine array analyses. DLS results showed that the differently prepared EVs had distinct size distributions depending on the filtration process. SDS-PAGE results revealed unique protein profiles that differentiated EVs under each condition. Treatment of macrophages with each EV sample markedly increased cell viability and size. The cytokine profiles produced by macrophages in response to each EV preparation revealed both common and distinguishable factors. This study has significance in revealing aspects of the biological characteristics of EVs produced by E. faecalis, which have previously been largely unknown. 2025-12-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/59909 Title: Erythropoietin-derived Non-erythropoietic Peptides Conferring Oxidative Stress Resistance to Keratinocytes and Fibroblasts Author(s): Han, Min Ae; Ashim, Janbolat; Ji, Youngheum; Kang, Eunho; Jeong, Minchan; Kim, Sung Jae; Yu, Wookyung; Kim, Jin Hae; Moon, Cheil; Lee, Chang-Hun Abstract: Erythropoietin (EPO) exerts tissue-protective effects; however, its erythropoietic activity limits broader use. Three EPO-derived peptides (ML1-C1/C2/C3) were designed from the C-helix of EPO to remove erythropoietic activity while retaining cell-protective activity. Circular dichroism and nuclear magnetic resonance spectroscopies were used to assess the solution structures of ML1-C1/C2/C3 peptides. The peptide activities for cytoprotection and growth support were assessed using skin-relevant cells, HaCaT cells and 3T3-L1 cells, which proposes an effect on skin epithelial keratinocytes and pre-adipocytic fibroblasts, respectively. Also, an erythroid-precursor cell line, TF-1, was used to evaluate the erythropoietic function of the three peptides. Spectroscopic analyses of ML1-C1/C2/C3 peptides revealed similar secondary structures and different flexibilities between the peptides. While ML1-C1 and ML1-C3 had highly flexible loop-like structures, ML1-C2 had less flexible loop-like structures. Also, their cellular effects vary in a cell type-dependent manner. The EPO-derived peptides can attenuate H2O2-induced loss of viability in HaCaT cells and 3T3-L1 cells. Under low-serum conditions, the three peptides promoted HaCaT proliferation, whereas only ML1-C1 improved 3T3-L1 proliferation. In TF-1 cells, none of the peptides increased cell viability or hemoglobin staining, whereas recombinant human EPO did, indicating the lack of erythropoietic activity of the peptides under experimental conditions. These findings support the potential of EPO-derived peptides as skin-protective agents and motivate future work for skin therapeutics or cosmetic purposes. https://scholar.dgist.ac.kr/handle/20.500.11750/59293 Title: Structure and function of the keratin 17 tail domain associated with keratin intermediate filament organization Author(s): Yeom, Jiwoo; Lee, Sanghoon; Ko, Young Ho; Hong, Eunmi; Kim, Jin Hae; Coulombe, Pierre A.; Lee, Chang-Hun Abstract: Keratins are the largest subgroup of intermediate filament proteins, forming 10-nm filaments from type I/II heterodimers, and occur primarily in epithelial cells. Keratin 6 (K6; type II) and Keratin 17 (K17; type I) show a complex expression pattern that includes induction following stress and in several diseases, including carcinomas. K17 is being used as a biomarker for several types of cancer. K6 and K17 sequences are respectively highly homologous to K5 and K14, which are expressed in the progenitor compartment of epidermis and related epithelia. The mechanical support roles of the K6/K17 and K5/K14 pairing require 10 nm filament assembly and the subsequent lateral association of these filaments to form thicker bundles. Previous studies showed that the non-helical tail domain of K14 is dispensable for 10 nm filament assembly but essential to the bundling of K5/ K14 filaments. Whether the K6/K17 pairing undergoes bundling, and whether the tail domain of K17 plays a role, is unknown. Here, we use sedimentation assays and electron microscopy to show that, when paired with K6, tailless K17 forms filaments that do not readily bundle. Nuclear magnetic resonance analysis revealed that the isolated K17 tail domain is an intrinsically disordered region (IDR). Follow-up studies with mutant K17 tail constructs suggest that IDR-like tail domains of keratins can form a curved local structure required for bundling and interact dynamically with other regions of keratin filaments in a flexible and heterogeneous manner. 2025-11-30T15:00:00Z