Publications by authors named "Jong Young Kwak"

Background: The natural polyphenolic compound known as Rosmarinic acid (RosA) can be found in various plants. Although its potential health benefits have been extensively studied, its effect on osteoarthritis (OA) progression and cartilage regeneration function still needs to be fully elucidated in OA animal models. This study elucidated the effect of RosA on OA progression and cartilage regeneration.

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An ideal extracellular matrix (ECM) replacement scaffold in a three-dimensional cell (3D) culture should induce in vivo-like interactions between the ECM and cultured cells. Highly hydrophilic polyvinyl alcohol (PVA) nanofibers disintegrate upon contact with water, resulting in the loss of their fibrous morphology in cell cultures. This can be resolved by using chemical crosslinkers and post-crosslinking.

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Aquaporins (AQPs) are a family of integral membrane proteins that selectively transport water and glycerol across the cell membrane. Because AQPs are involved in a wide range of physiological functions and pathophysiological conditions, AQP-based therapeutics may have the broad potential for clinical utility, including for disorders of water and energy balance. However, AQP modulators have not yet been developed as suitable candidates for clinical applications.

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Lipid droplets (LDs) store energy and supply fatty acids and cholesterol. LDs are a hallmark of chronic nonalcoholic fatty liver disease (NAFLD). Recently, studies have focused on the role of hepatic macrophages in NAFLD.

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Background: Ginsenoside Rg3, a primary bioactive component of red ginseng, has anti-cancer effects. However, the effects of Rg3-enriched ginseng extract (Rg3RGE) on apoptosis and autophagy in breast cancer have not yet been investigated. In the present study, we explored the anti-tumor effects of Rg3RGE on breast cancer cells stimulated CoCl, a mimetic of the chronic hypoxic response, and determined the operative mechanisms of action.

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An integrated multifunctional light-sheet nanoscopy (iMLSN) combined with differential interference contrast, total internal reflection, epifluorescence, a super-resolution radial fluctuation-stream module, and a wavelength-dependent light sheet was developed to simultaneously realize the six-dimensional (6D) vector-valued (three coordinates + rotational dynamics (azimuth and elevation angles) + transport speed) tracking of anisotropic nanoparticles in single living cells. The wavelength-dependent asymmetric scattering of light by gold nanorods was used to trigger signals depending on the polarizer angle, and real-time photo-switching was achieved by turning the polarizer, obtaining a series of super-resolution images, and tracking using different polarization directions and two channels. This technique was employed to directly observe native gold nanorods (AuNRs; 5 nm diameter × 15 nm length) and surface-functionalized AuNRs during their endocytosis and transport at the upper and attaching side membrane regions of single living cells, revealing that the AuNRs bound to the membrane receptors.

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4-O-methylascochlorin (MAC) is a 4-fourth carbon-substituted derivative of ascochlorin, a compound extracted from a phytopathogenic fungus . MAC induces apoptosis and autophagy in various cancer cells, but the effects of MAC on apoptosis and autophagy in cervical cancer cells, as well as how the interaction between apoptosis and autophagy mediates the cellular anticancer effects are not known. Here, we investigated that MAC induced apoptotic cell death of cervical cancer cells without regulating the cell cycle and promoted autophagy by inhibiting the phosphorylation of serine-threonine kinase B (Akt), mammalian target of rapamycin (mTOR), and 70-kDa ribosomal protein S6 kinase (p70S6K).

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The accumulation of hepatic lipid droplets (LDs) is a hallmark of non-alcoholic fatty liver disease (NAFLD). Appropriate degradation of hepatic LDs and oxidation of complete free fatty acids (FFAs) are important for preventing the development of NAFLD. Histone deacetylase (HDAC) is involved in the impaired lipid metabolism seen in high-fat diet (HFD)-induced obese mice.

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In this study, we developed a three-dimensional (3D) in vitro infection model to investigate the crosstalk between phagocytes and microbes in inflammation using a nanofibrous membrane (NM). Poly(ε-caprolactone) (PCL)-NMs (PCL-NMs) were generated via electrospinning of PCL in chloroform. and phagocytes were able to adhere to the nanofibers and phagocytes engulfed in the PCL-NM.

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Three-dimensional (3D) cancer cell culture systems have been developed to aid the study of molecular mechanisms in cancer development, identify therapeutic targets, and test drug candidates. In this study, we developed a strategy for mimicking the hypoxic tumor microenvironment in a 3D cancer cell culture system using multi-layer, nanofibrous poly(ε-caprolactone) (PCL) scaffold (pNFS)-based cancer cell cultures. We found that human colon cancer cells infiltrated pNFS within 3 days and could be cultured three-dimensionally within the NFS.

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Dendritic cells (DCs) have the ability to stimulate naïve T cells that coordinate subsequent adaptive response toward an inflammatory response or tolerance depending on the DC differentiation level. Inotodiol, a lanostane triterpenoid found in (wild Chaga mushroom), is a natural compound with a wide range of biological activities. In this study, we investigated whether inotodiol promotes the maturation of bone marrow-derived DCs (BMDCs) and inotodiol-treated BMDCs induce T cell activation.

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Angiogenesis is critical for local tumor growth. This study aimed to develop a three-dimensional two-layer co-culture system to investigate effects of cancer cells on the growth of endothelial cells (ECs). Poly(ε-caprolactone) (PCL) nanofibrous membranes were generated via electrospinning of PCL in chloroform (C-PCL-M) and chloroform and dimethylformamide (C/DMF-PCL-M).

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The aim of this study was to evaluate whether apoptosis of lymphocytes is modulated by stimulation by lipopolysaccharide (LPS) of or muramyl dipeptide (MDP). Cell populations were obtained by lavaging of the mammary glands 24, 48, 72, and 168 hours following intramammary induced inflammation. The portion of apoptotic lymphocytes peaked at 48 hours after treatment with LPS or MDP.

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This review focuses on the expanding role of marine collagen (MC)-based scaffolds for biomedical applications. A scaffold-a three-dimensional (3D) structure fabricated from biomaterials-is a key supporting element for cell attachment, growth, and maintenance in 3D cell culture and tissue engineering. The mechanical and biological properties of the scaffolds influence cell morphology, behavior, and function.

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Recently, three-dimensional (3D) cell culture and tissue-on-a-chip application have attracted attention because of increasing demand from the industries and their potential to replace conventional two-dimensional culture and animal tests. As a result, numerous studies on 3D in-vitro cell culture and microfluidic chip have been conducted. In this study, a microfluidic chip embracing a nanofiber scaffold is presented.

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Lymphoma is a heterogeneous disease with a highly variable clinical course and prognosis. Improving the prognosis for patients with relapsed and treatment-resistant lymphoma remains challenging. Current drug testing models based on 2D cell culture lack natural tissue-like structural organization and result in disappointing clinical outcomes.

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Three-dimensional (3D) in vitro tissue or organ models can effectively mimic the complex microenvironment of many types of human tissues for medical applications. Unfortunately, development of 3D cancer models, which involve cancer/stromal cells in a 3D environment, has remained elusive due to the extreme complexity of the tumor microenvironment (TME) and the stepwise progression of human cancer. Here, we developed hepatocellular carcinoma (HCC) models, which consist of fibroblasts as stromal cells, HCC cells, and a nanofibrous membrane to mimic the complex TME.

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In general, a drug candidate is evaluated using 2D-cultured cancer cells followed by an animal model. Despite successful preclinical testing, however, most drugs that enter human clinical trials fail. The high failure rates are mainly caused by incompatibility between the responses of the current models and humans.

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Skin diseases associated with inflammation or oxidative stress represent the most common problem in dermatology. The present study demonstrates that fish scale collagen peptides (FSCP) protect against CoCl-induced cytotoxicity and TNF--induced inflammatory responses in human HaCaT keratinocyte cells. Our study is the first to report that FSCP increase cell viability and ameliorate oxidative injury in HaCaT cells through mechanisms mediated by the downregulation of key proinflammatory cytokines, namely, TNF-, IL-1, IL-8, and iNOS.

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Endothelial cells (ECs) form a monolayer lining over the entire vascular wall and play an important role in maintaining vascular homeostasis and cancer metastasis. Loss of proper endothelial function can lead to vascular diseases. Therefore, the endothelial monolayer is particularly important in tissue regeneration and mimicking vascular tissue in vitro.

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Aquaporin-3 (AQP3) is an integral membrane protein that facilitates the transport of water and glycerol across cell membranes. However, the precise localization and function of AQP3 in skeletal muscles is currently unknown. In this study, we investigated the capacity of AQP3 knockout mice to perform a single bout of exhausting exercise and analyzed the parameters related to skeletal muscle energy metabolism during exhausting exercise.

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An artificial three-dimensional (3D) culture system that mimics the tumor microenvironment in vitro is an essential tool for investigating the cross-talk between immune and cancer cells in tumors. In this study, we developed a 3D culture system using an electrospun poly(ε-caprolactone) (PCL) nanofibrous scaffold (NFS). A hybrid NFS containing an uninterrupted network of nano- and submicron-scale fibers (400 nm to 2 µm) was generated by deposition onto a stainless steel mesh instead of an aluminum plate.

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Background/aims: CD11c is a dendritic cell marker in humans, which potentially induces a cytotoxic effect on lymphoma cells. Forkhead boxP3 (FOXP3) is a regulator of T lymphocyte in the microenvironment of the lymphoma. The principal objective of this study was to determine whether the tumors' microenvironment expressions of CD11c and FOXP3 are predictive of clinical outcomes in diffuse large B-cell lymphoma (DLBCL) patients receiving treatment with rituximab, cyclophosphamide, anthracycline, vincristine, and prednisone (R-CHOP) combination chemotherapy.

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Stichoposide D (STD) is a marine triterpene glycoside isolated from sea cucumbers. We examined the molecular mechanisms underlying the antitumor activity of STD in human leukemia cells. The role of Fas (CD95), ceramide synthase 6 (CerS6) and p38 kinase during STD-induced apoptosis was examined in human leukemia cells.

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One of the most challenging objectives of 3D cell culture is the development of scaffolding materials with outstanding biocompatibility and favorable mechanical strength. In this study, we fabricated a novel nanofibrous scaffold composed of fish collagen (FC) and polycaprolactone (PCL) blends by using the electrospinning method. Nanofibrous scaffolds were characterized using a scanning electron microscope (SEM), and it was revealed that the diameter of nanofibers decreased as FC content was increased in the FC/PCL composite nanofibers.

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