Eunae Cho

Insufficient sleep can disrupt circadian organization and adversely affect skin condition. Perturbation of the cutaneous clock, which governs skin homeostasis, may contribute to this deterioration. In our study, a six-botanical mixture extract increased PER2 promoter-driven luciferase output in HaCaT keratinocytes, and reduced IL6 and CXCL10 expression, two PER2-associated inflammatory mediators. Separately, a 4-week single-arm pilot study evaluated a cream containing 2.00% (w/w) of a liquid preparation of this extract, applied nightly by 22 women aged 40–70 years with poor sleep quality. Skin indicators, sleep, mood, and salivary melatonin and cortisol were assessed as changes from baseline at week 4. The 13 skin indicators changed from baseline across the anti-aging, barrier, complexion, and dark-circle categories (Cohen’s d 0.47–4.81). Sleep duration increased, whereas PSQI-K and PHQ-9 scores decreased; the melatonin day–night difference increased (d = 0.75); cortisol measures did not change significantly. No adverse skin reactions were reported. These exploratory findings do not establish product-attributable efficacy or a causal PER2-mediated mechanism; placebo, vehicle, expectancy, seasonal, behavioral, and regression-to-the-mean effects cannot be excluded. A randomized, vehicle-controlled study is required, with prespecified primary outcomes, denser circadian sampling, and clock activity measured directly in treated skin.

Skin aging is characterized by fibroblast senescence, extracellular matrix (ECM) degradation, and impaired wound healing, driven by oxidative stress and telomere dysfunction. Here, we investigated the anti-aging effects of a standardized microwave-assisted propolis extract (MAPE) in both H₂O₂-induced and replicative senescence models of human dermal fibroblasts (HDFs). MAPE significantly reduced reactive oxygen species (ROS) accumulation and enhanced antioxidant gene expression (NQO1, GCLM), indicating activation of NRF2-dependent defense pathways. It suppressed senescence markers (CDKN2A, CDKN1A, IL6), decreased SA-β-gal activity, and attenuated inflammaging. Moreover, MAPE inhibited MMP1 expression, restored COL1A1, and improved fibroblast wound closure, thereby maintaining ECM homeostasis. Importantly, MAPE modulated Wnt/β-catenin signaling by upregulating WNT3A and LEF1 while suppressing DKK1, and increased TERT expression, suggesting involvement of telomerase-related regulatory pathways. These effects resembled those of CHIR99021, a canonical Wnt activator, while providing additional antioxidant protection. Together, our findings suggest that MAPE is a propolis-derived bioactive ingredient that counteracts fibroblast senescence through coordinated modulation of NRF2 and Wnt/β-catenin–TERT signaling pathways, supporting its potential as a cosmeceutical ingredient for mitigating skin aging.

Kyung-Baeg Roh, Suwon Jeon, WonTae Jo, A Hyung Jeong, Hyanggi Ji, Eunae Cho, Jihye Lee, Deokhoon Park, and Eunsun Jung. Journal of the Korean Society of Food Science and Nutrition 2026;55:1-10. https://doi.org/10.3746/jkfn.2026.55.1.1

Extracellular vesicles (EVs) derived from lactic acid bacteria have gained attention as mediators of host-microbe interaction. However, their molecular characteristics compared to cell-derived vesicles (CDVs) remain poorly understood. In this study, we isolated EVs and CDVs from Lactobacillus rhamnosus and characterized them throughout proteomic and functional analyses. Both vesicle types displayed spherical morphology as observed by nanoparticle tracking analysis and transmission electron microscopy. Western blotting revealed distinct protein profiles, with HSP70 specifically detected in EVs. Proteomic profiling using LC-MS/MS identified a total of 1,342 proteins, including 114 unique to CDVs. Differential expression proteins analysis showed 70 proteins upregulated and 81 downregulated in EVs. Gene Ontology (GO) analysis indicated that EVs were enriched in proteins related to signal transduction, environmental adaptation, and transmembrane transport, while CDVs showed enrichment in ribosomal and nucleic acid metabolism-related proteins. Functional assays further demonstrated that EVs exhibited significantly stronger antioxidant and anti-inflammatory activities than CDVs. These findings suggest that L. rhamnosus -derived EVs possess distinct proteomic signatures and superior bioactivity, supporting their potential role in probiotic-based therapeutic strategies, particularly for skin health.

Extracellular vesicles (EVs) derived from probiotic bacteria have recently emerged as postbiotic mediators that regulate host cellular responses. This study investigated the effects of EVs from Lactobacillus rhamnosus BS-Pro-08, isolated from kefir grains (Lacto EV), on adipocyte differentiation and lipid metabolism. Lacto EV treatment markedly suppressed the differentiation of 3T3-L1 preadipocytes into mature adipocytes, as reflected by reduced lipid accumulation and decreased expression of the adipogenic transcription factors peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα). This inhibitory effect was most pronounced at the early stage of adipogenesis. In mature adipocytes, Lacto EV enhanced lipolysis in a dose-dependent manner, accompanied by increased glycerol release and total lipase activity. Interestingly, these lipolytic responses occurred despite reduced protein levels of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL), suggesting that Lacto EVs may mediate an EV-enhanced lipolysis that is not fully explained by canonical ATGL/HSL signaling. Collectively, these findings demonstrate that Lacto EV modulates both adipogenic and lipolytic processes in vitro, providing insight into the metabolic actions of probiotic-derived vesicles.

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.

The aim of this study was to investigate the effect of Sargassum fusiforme extract (SFE) on melanogenesis and its mechanism both in vitro and ex vivo. The melanogenic-inducing effect of SFE was evaluated using a melanin contents assay and a cellular tyrosinase activity assay. To investigate whether SFE could protect melanocytes against oxidative stress, hydrogen peroxidase was used. The molecular mechanism underlying the effect of SFE on melanogenesis was determined via Western blot analysis of tyrosinase, a microphthalmia-associated transcription factor (MITF), and a phosphorylated cAMP response element-binding protein (p-CREB) expression. The degree of pigmentation in a 3D skin model was determined by measuring the L* values. Contents of melanin in ex vivo human hair follicles were evaluated via Fontana–Masson staining. SFE significantly increased melanin contents and cellular tyrosinase activity in human epidermal melanocytes. SFE also increased the phosphorylation of CREB and the protein levels of tyrosinase and MITF. Moreover, SFE attenuated oxidative stress-induced cytotoxicity and depigmentation. Finally, the melanogenesis promoting effect of SFE was confirmed in both a 3D skin model and ex vivo human hair follicles. These findings suggest that SFE can induce melanogenesis via the cAMP/PKA/CREB signaling pathway in human epidermal melanocytes through its hyperpigmentation activity.

This study investigated the effects of the Albizia julibrissin Leaf extracts (AJLE) on adipocytes using 3T3-L1 cells. AJLE inhibited adipogenesis by reducing the expression of peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer binding proteins (C/EBPs) that regulate enzymes involved in fat synthesis and storage, and subsequently reduced intracellular lipid droplets, glycerol-3-phosphate dehydrogenase (GPDH), and triglyceride (TG). AJLE also increased the expression of brown adipocyte markers, such as uncoupling protein-1 (UCP-1), PR/SET domain 16 (PRDM16), and bone morphogenetic protein 7 (BMP7) by inducing the differentiation of brown adipocytes, as shown by a decrease in the lipid droplet sizes and increasing mitochondrial mass. AJLE increased the expression of transcription factor A, mitochondrial (TFAM), mitochondrial DNA (mtDNA) copy number, and UCP-1 protein expression, all of which are key factors in regulating mitochondrial biogenesis. AJLE-induced browning was shown to be regulated by the coordination of AMPK, p38, and SIRT1 signaling pathways. The ability of AJLE to inhibit adipogenesis and induce brown adipocyte differentiation may help treat obesity and related diseases.

이 글의 목적은 ‘고마쓰가와 사건(小松川事件)’의 범인으로 알려진 재일조선인 사형수 이진우와 저널리스트 박수남 사이에 교환된 서신을 ‘감옥 글쓰기(prison writing)’라는 텍스트-실천의 사례로 분석하고, 재일조선인의 삶/죽음에 관한 자기 기획의 각본들을 조명하는 것이다. 특히 해당 사건으로 촉발된 감옥 글쓰기의 공저자라 할 수 있는 두 재일조선인의 엇갈린 사유가 ‘고유명(proper name)’의 사용과 변천에서 결정적으로 확인된다는 점에 주목한다. 이러한 관점을 통해 ‘고마쓰가와 사건’ 이후 감옥 글쓰기의 방식으로 생산된 자기서사를 다양한 층위의 명명 속에 구성되는 주체의 기획에 관한 각본들로 독해할 수 있다. 먼저 주목되는 것은 이진우가 한글 서명을 시도함으로써 자신의 이름에 내포된 단독성(singularity)을 주장할 수 있었다는 점이다. ‘진우’라는 한글 이름은 오직 그 자신의 글쓰기 속에서, 서명이라는 형식적 엄정성과 선언성을 통해 수행된 것이며, 거기서 우리는 어떤 이유로도 공격받거나 손상되거나 침범당할 수 없는 단독성을 발견하게 된다. 한편, 박수남은 1963년 『죄와 죽음과 사랑』으로부터 16년 후인 1979년 출간된 『이진우 전서간집』에서, 이진우라는 이름을 보다 전형적이고 집단적인 이름으로 확장하는 시도를 보여준다. 그것은 1968년 개봉한 오시마 나기사의 영화 〈교사형〉 속에 나오는 조선인 ‘R’과 ‘R들(Rs)’을 ‘또 다른 R’로 재전유하는 방식이다. 박수남이 재일조선인의 ‘전형’으로 ‘받아들여짐으로써 죽음을 맞은’ 〈교사형〉 속 R의 표상을 비틀어 ‘죽음’이 아닌 새로운 ‘삶’의 방향을 찾는 과정은, 이진우, 김희로, 서승 ․ 서준식 형제처럼 그 정치사회적 함의는 각각 다르지만 공통적으로 감옥 글쓰기의 저자였던 남성/민족 주체의 글쓰기와 접속하면서도, 이를 ‘아직 이름을 가지지 않은 존재들’의 시간과 연결하는 감각에 의해 실천될 수 있었다.

Senescent fibroblasts progressively deteriorate the functional properties of skin tissue. Senescent cells secrete senescence-associated secretory phenotype (SASP) factor, which causes the aging of surrounding non-senescent cells and accelerates aging in the individuals. Recent findings suggested the senomorphic targeting of the SASP regulation as a new generation of effective therapeutics. We investigated whether Isatis tinctoria L. leaf extract (ITE) inhibited senescence biomarkers p53, p21^CDKN1A, and p16^INK4A gene expression, and SASP secretions by inhibiting cellular senescence in the replicative senescent human dermal fibroblast (RS-HDF). ITE has been demonstrated to inhibit the secretion of SASP factors in several senomorphic types by regulating the MAPK/NF-κB pathway via its inhibitory effect on mTOR. ITE suppressed the inflammatory response by inhibiting mTOR, MAPK, and IκBα phosphorylation, and blocking the nuclear translocation of NF-κB. In addition, we observed that autophagy pathway was related to inhibitory effect of ITE on cellular senescence. From these results, we concluded that ITE can prevent and restore senescence by blocking the activation and secretion of senescence-related factors generated from RS-HDFs through mTOR-NF-κB regulation.