Yeong-Bin Baek

Zika virus (ZIKV) substantially relies on host lipid metabolism, presenting a prime target for host-directed antivirals. To identify host-directed antiviral interventions while circumventing interferon-mediated transcriptomic masking, we curated a dual-virus (dengue and ZIKV) gene signature to query the Connectivity Map. Top lipid-lowering candidates were validated using a reporter virus (rZIKV-Venus) and an authentic wild-type (WT) ZIKV in Vero E6 cells—a model deliberately selected for its interferon deficiency to isolate pure metabolic responses. Dose–response screening of 67 prioritized compounds identified atorvastatin, rosuvastatin, and clofibrate as potent ZIKV inhibitors. Statin–clofibrate combinations exhibited strong synergy, with fractional inhibitory concentration index (FICI) values of 0.203 (atorvastatin–clofibrate) and 0.117 (rosuvastatin–clofibrate) for the 4:1 clofibrate-to-statin ratio and an optimized selectivity index. Mechanistically, exogenous oleic acid supplementation induced significant metabolic complementation, significantly restoring both host lipid droplet (LD) abundance and ZIKV replication readouts suppressed by the dual treatment. Relative LD intensity strongly correlated with viral intensity in both models (Pearson r = 0.951 and 0.956, respectively; both p < 0.0001). These findings demonstrate that concurrent pharmacological modulation of host lipid metabolism exerts synergistic anti-ZIKV effects, highlighting highly curated transcriptomic repurposing as a mechanistic prioritization strategy for host-directed antiviral discovery.

Emerging influenza viruses and mosquito-borne flaviviruses continue to challenge animal and public health, highlighting the need for antivirals that remain effective after infection. This study evaluated the in vitro activity of a 70% ethanolic whole-specimen extract of the marine bivalve Entodesma navicula (ENE) against influenza A/Puerto Rico/8/1934 (H1N1; A/PR8), A/Wisconsin/15/2009 (H3N2), influenza B/Florida/78/2015, Zika virus, and dengue virus serotype 2. Antiviral activity was assessed using time-of-addition analysis, viability-based cytopathic-effect assays, reverse-transcription quantitative PCR, infectious virus titration, immunofluorescence, Western blotting, and flow cytometry. In the A/PR8 model, pre- and co-treatment produced no consistent inhibition. By contrast, post-infection ENE suppressed all tested viruses. For A/PR8, Zika virus, and dengue virus, this activity was supported by reduced viral genome abundance, infectious progeny, and viral antigen expression. In A/PR8-infected A549 cells, ENE reduced phosphorylation of receptor-interacting serine/threonine-protein kinase 3 (RIPK3) and mixed lineage kinase domain-like pseudokinase (MLKL). ENE also reduced the proportion of cells positive for phosphorylated MLKL within Zika- and dengue-virus-infected Vero E6 populations. These findings identify E. navicula as an underexplored source of post-infection antiviral bioactivity associated with attenuated necroptosis-related signaling. Isolation of active constituents and causal validation in primary cells and animal models are needed.

The genus Peucedanum (Apiaceae) contains diverse coumarins and related secondary metabolites with a wide range of pharmacological activities; however, the antiviral potential of Korean taxa remains largely unexplored. In this study, we evaluated the cytotoxicity and anti-influenza activity of aerial-part extracts from Korean Peucedanum taxa and the allied species Sillaphyton podagraria. Twenty-six ethanol extracts, comprising 24 accessions representing eight identified taxa and two unidentified Peucedanum samples, were screened against influenza A/Puerto Rico/8/34 (H1N1) virus in MDCK cells. Cytotoxicity and antiviral activity were assessed using MTT-based assays, and the half-maximal inhibitory concentration (IC₅₀), half-maximal cytotoxic concentration (CC₅₀), and selectivity index (SI) were determined. Most extracts showed low cytotoxicity, with CC₅₀ values > 100 μg/mL. P. terebinthaceum var. deltoideum showed the strongest and most consistent activity across all three accessions, with IC₅₀ values of 6.42 to 12.18 μg/mL and SI values ranging from >8.21 to >15.57. One P. japonicum extract (Pj2) was also active (IC₅₀ = 15.52 μg/mL; SI > 6.44). Comparative chromatographic profiling further revealed taxon-specific chemical patterns. Collectively, these findings identify P. terebinthaceum var. deltoideum as a promising source of antiviral compounds and highlight the utility of a taxonomy-guided approach for bioprospecting and natural-product-based antiviral discovery.

Atopic dermatitis (AD) is a chronic inflammatory skin disease requiring long-term management in companion animals. This study evaluated the butanol fraction of Aster yomena extract (AY BuOH) as an orally administered dietary supplement candidate for atopic skin health using a DNCB-induced AD-like mouse model. AY BuOH was chemically profiled by UPLC-ESI-QToF-MS/MS and quantified for major marker compounds. Male SKH-1 mice were allocated to normal control, DNCB control, oclacitinib-treated, or AY BuOH-treated groups (2.5–640 mg/kg/day) for five weeks. AY BuOH contained abundant rutin and dicaffeoylquinic acid (DCQA) isomers, including 3,4-, 3,5-, and 4,5-DCQA isomers. Oral AY BuOH administration, particularly at intermediate doses, reduced modified dermatitis severity scores, gross skin lesions, serum immunoglobulin E levels, and cutaneous interleukin-4 and interleukin-13 concentrations, with effects comparable to those observed in the oclacitinib reference group in selected endpoints. AY BuOH also partially restored splenic Th1/Th2 balance and attenuated epidermal and dermal thickening. The highest dose, 640 mg/kg/day, was associated with body weight loss and elevated hepatic enzyme activities, suggesting potential hepatic stress. These findings provide preclinical evidence that AY BuOH may serve as a standardized plant-derived dietary supplement or functional feed additive candidate for companion animal skin health, pending target-species safety and efficacy validation.

Mammary tumor is one of the most prevalent cancers in female companion dogs. Current chemotherapeutic treatments are often limited by high toxicity and financial burden, highlighting the need for safer and more accessible therapeutic alternatives. This study aimed to evaluate the anticancer potential of the methanol extract of Polytrichastrum alpinum, a moss species native to Antarctica, in mammary tumor cell lines derived from companion dogs. Two canine mammary tumor cell lines, MGT316 and MGT612, were treated with various concentrations of Polytrichastrum alpinum methanol extract. Cell viability, colony-forming ability, cell cycle distribution, apoptosis, migration, and invasion were assessed. Cytotoxic effects on normal canine epithelial cells were also evaluated to compare responses between tumor and non-tumorigenic cells. Polytrichastrum alpinum methanol extract significantly reduced cell viability and colony-forming ability in a dose-dependent manner. It induced G0/G1 cell cycle arrest and promoted apoptosis in both tumor cell lines. Additionally, the extract effectively inhibited cell migration and invasion. Notably, minimal cytotoxic effects were observed in normal canine epithelial cells, indicating differential sensitivity between tumor and non-tumorigenic cells. These findings demonstrate that Polytrichastrum alpinum methanol extract exerts antiproliferative, pro-apoptotic, and anti-invasive effects on mammary tumor cells of companion dogs, indicating its potential as a natural therapeutic agent. Furthermore, given the relevance of canine mammary tumors as a comparative model, this study may provide valuable translational insights for human breast cancer research within a One Health framework.

Ran Hui Choi, Beom Ki Park, Yeong-Bin Baek, Jun-Gyu Park, Dae Sung Yoo, Bock-Gie Jung, Sang-Ik Park, Myeong Ja Choi, Ji-Young Chung, Byung-Suk Jeon, Jun Bong Lee. Korean J. Vet. Serv. 2026;49:75-82. https://doi.org/10.7853/kjvs.2026.49.1.75

Jin Hee Choi, Jin Ju Kim, Geum Ju Lim, Ji Hyeong Bang, Yeong-Bin Baek, Jun-Gyu Park, Dae Sung Yoo, Bock-Gie Jung, Sang-Ik Park, Sook Hyun Kim, Ji-Young Chung, Byung-Suk Jeon, Jun Bong Lee. Korean J. Vet. Serv. 2026;49:69-74. https://doi.org/10.7853/kjvs.2026.49.1.69

Samo Jo, Geontae Kim, Jisung Park, Chae-rim Kwak, Duhyun Kim, Han Gyu Lee, Eun-Yeong Bok, Jun Bong Lee, Yeong-Bin Baek, Jun-Gyu Park, Dae Sung Yoo, Sang-Ik Park, Inje Jeong, Ji-Young Jung, Bock-Gie Jung. Korean J. Vet. Serv. 2026;49:13-9. https://doi.org/10.7853/kjvs.2026.49.1.13

Inflammatory mammary carcinoma (IMC) is an aggressive mammary carcinoma phenotype characterized by tumor emboli within superficial dermal lymphatic vessels and early metastasis. A captive Bengal tiger (Panthera tigris tigris) presented with large abdominal mammary masses and regional lymphadenopathy; contrast-enhanced computed tomography also revealed a pulmonary nodule. Postmortem examination and histopathology confirmed mammary carcinoma with dermal lymphatic tumor emboli and metastases to regional lymph nodes and the lung. Tumor emboli were cytokeratin positive, supporting epithelial origin and an IMC diagnosis, and neoplastic cells were immunopositive for cytokeratin with concurrent vimentin immunoreactivity. This case highlights the clinicopathologic basis of IMC and the diagnostic importance of including full-thickness skin and adjacent subcutis in the sampling plan.

Yeonju Park, Jin-Woo Jung, Sehyeon Park, Yeongbin Baek, Sang-Ik Park, Jun-Gyu Park, Seungjo Park. J Vet Clin 2026;43:54-60. https://doi.org/10.17555/jvc.2026.43.1.54