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Nepal M.,Chonbuk National University | Li L.,Chonbuk National University | Li L.,Hanpoong Pharm and Foods Co. | Cho H.K.,Hanpoong Pharm and Foods Co. | And 2 more authors.
Food and Chemical Toxicology

Endochondral bone formation occurs when mesenchymal cells condense to differentiate into chondrocytes, the primary cell types of cartilage. The aim of the present study was to identify novel factors regulating chondrogenesis. We investigated whether kaempferol induces chondrogenic differentiation in clonal mouse chondrogenic ATDC5 cells. Kaempferol treatment stimulated the accumulation of cartilage nodules in a dose-dependent manner. Kaempferol-treated ATDC5 cells stained more intensely with alcian blue staining than control cells, suggesting greater synthesis of matrix proteoglycans in the kaempferol-treated cells. Similarly, kaempferol induced greater activation of alkaline phosphatase activity than control cells, and it enhanced the expression of chondrogenic marker genes, such as collagen type I, collagen type X, OCN, Runx2, and Sox9. Kaempferol induced an acute activation of extracellular signal-regulated kinase (ERK) but not c-jun N-terminal kinase or p38 MAP kinase. PD98059, an inhibitor of MAPK/ERK, decreased in stained cells treated with kaempferol. Furthermore, kaempferol greatly expressed the protein and mRNA levels of BMP-2, suggesting chondrogenesis was stimulated via a BMP-2 pathway. Taken together, our results suggest that kaempferol has chondromodulating effects via an ERK/BMP-2 signaling pathway and could potentially be used as a therapeutic agent for bone growth disorders. © 2013 Elsevier Ltd. Source

Poudel A.,Wonkwang University | Kim S.-G.,Wonkwang University | Lamichhane R.,Wonkwang University | Kim Y.-K.,Wonkwang University | And 2 more authors.
Journal of Chromatographic Science

A specific and reliable ultra-performance liquid chromatography-diode array detection method has been developed and validated for the quantitative assessment of a traditional Oriental herbal formulation, Samhwangsasim-tang (SST). A Halo reversed-phase amide column (2.7 μm, 4.6 × 150 mm) was used to separate marker compounds; detection was conducted by ultraviolet absorbance at 250 nm. The column temperature was maintained at 45°C. A mobile phase consisting of acetonitrile (A) and 0.1% trifluoroacetic acid in water (B) was found to be suitable for the separation, at a flow rate of 1.8 mL/min with gradient elution. Linearity, specificity, precision and recovery were calculated to validate the method and instrumentation. Under the described conditions, all marker compounds (rhaponticin, berberine, palmatine, baicalin, baicalein and wogonin) were collected within 25 min. All calibration curves of components showed good linearity (correlation coefficient > 0.9996). The limit of detection and limit of quantification ranged from 0.08-3.05 and 0.23-8.12 μg/mL, respectively. The relative standard deviation (RSD) and repeatability values of intra-day and inter-day precision were less than 2.30, 2.99 and 1.82%, respectively. In the recovery test, the accuracy ranged from 97.56-103.30% with RSD values less than 2.63%. The developed method was simple, specific, sensitive, accurate, precise and reproducible for the quantification of the active chemical constituents of SST. The simultaneous analysis of the contents of marker compounds in different SST samples prepared by different extraction procedures and different commercial products was successfully evaluated. © 2013 The Author. Source

Li L.,Chonbuk National University | Li L.,Woosuk University | Eun J.S.,Woosuk University | Nepal M.,Chonbuk National University | And 4 more authors.
Biomolecules and Therapeutics

Endochondral bone formation is the process by which mesenchymal cells condense to become chondrocytes, which ultimately form new bone. The process of chondrogenic differentiation and hypertrophy is critical for bone formation and as such is regulated by many factors. In this study, we aimed to indentify novel factors that regulate chondrogenesis. We investigated the possible role of isopsoralen in induction of chondrogenic differentiation in clonal mouse chondrogenic ATDC5 cells. Isopsoralen treatment stimulated the accumulation of cartilage nodules in a dose-dependent manner. Further, ATDC5 cells treated with isopsoralen were stained more intensely with Alcian blue than control cells, suggesting that isopsoralen increases the synthesis of matrix proteoglycans. Similarly, isopsoralen markedly induced the activation of alkaline phosphatase activity compared with control cells. Isopsoralen enhanced the expressions of chondrogenic marker genes such as collagen II, collagen X, OCN, Smad4 and Sox9 in a time-dependent manner. Furthermore, isopsoralen induced the activation of extracellular signal-regulated kinase (ERK) and p38 MAP kinase, but not that of c-jun N-terminal kinase (JNK). Isopsoralen significantly enhanced the protein expression of BMP-2 in a time-dependent manner. PD98059 and SB 203580, inhibitors of ERK and p38 MAPK, respectively, decreased the number of stained cells treated with isopsoralen. Taken together, these results suggest that isopsoralen mediates a chondromodulating effect by BMP-2 or MAPK signaling pathways, and is therefore a possible therapeutic agent for bone growth disorders. © 2012 The Korean Society of Applied Pharmacology. Source

Lee D.-S.,Inha University | Ko W.,Wonkwang University | Yoon C.-S.,Wonkwang University | Kim D.-C.,Wonkwang University | And 11 more authors.
Evidence-based Complementary and Alternative Medicine

The brain is vulnerable to oxidative stress and inflammation that can occur as a result of aging or neurodegenerative diseases. Our work has sought to identify natural products that regulate heme oxygenase (HO)-1 and to determine their mechanism of action in neurodegenerative diseases. KCHO-1 is a novel herbal therapeutic containing 30% ethanol (EtOH) extracts from nine plants. In this study, we investigated the antineuroinflammatory effects of KCHO-1 in lipopolysaccharide- (LPS-) treated mouse BV2 microglia. KCHO-1 inhibited the protein expression of inducible nitric oxide synthase (iNOS), iNOS-derived nitric oxide (NO), cyclooxygenase- (COX-) 2, and COX-2-derived prostaglandin E2 (PGE in LPS-stimulated BV2 microglia. It also reduced tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6 production. This effect was correlated with the suppression of inhibitor of nuclear factor kappa B-α (IB-α) phosphorylation and degradation and nuclear factor kappa B (NF-B) translocation and DNA binding. Additionally, KCHO-1 upregulated HO-1 expression by promoting nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) in mouse BV2 microglia. Tin protoporphyrin (SnPP), an HO activity inhibitor, was used to verify the inhibitory effects of KCHO-1 on proinflammatory mediators and proteins associated with HO-1 expression. Our data suggest that KCHO-1 has therapeutic potential in neurodegenerative diseases caused by neuroinflammation. © 2014 Dong-Sung Lee et al. Source

Yoon C.-S.,Wonkwang University | Kim D.-C.,Wonkwang University | Ko W.-M.,Wonkwang University | Kim K.-S.,Wonkwang University | And 7 more authors.
Korean Journal of Pharmacognosy

Grapes has long been used for food, and reported as containing polyphenol which has antioxidant and anti-cancer effects. Neuroinflammation is chronic inflammation at the brain, lead to neurodegenerative diseases. In this study, quercetin-3-O-glucuronide (QG) isolated from the leaf of Vitis labruscana has anti-neuroinflammatory effects. QG were investigated using MTT assay, western blot, nitric oxide (NO) assay, prostaglandin E2(PGE2) assay, cytokine assay in lipopolysaccharide (LPS)-induced inflammation in BV2 cells. QG dose-dependently attenuated the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), accordingly inhibited the production of NO and PGE2. QG decreases the levels of proinflammatory cytokine such as tumor necrosis factor-α (TNF-α), interlukin-1β (IL-1β). Thereby, QG may offer therapeutic potential for treatment of neurodegenerative disease related to neuroinflammation. Source

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