• Journal of Periodontal and Implant Science
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• v.43 no.4
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• pp.168-176
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• 2013

Purpose: The purpose of the current study was to examine the effect of dexamethasone (Dex) at various concentrations on the apoptosis and mineralization of human periodontal ligament (hPDL) cells. Methods: hPDL cells were obtained from the mid-third of premolars extracted for orthodontic reasons, and a primary culture of hPDL cells was prepared using an explant technique. Groups of cells were divided according to the concentration of Dex (0, 1, 10, 100, and 1,000 nM). A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed for evaluation of cellular viability, and alkaline phosphatase activity was examined for osteogenic differentiation of hPDL cells. Alizarin Red S staining was performed for observation of mineralization, and real-time polymerase chain reaction was performed for the evaluation of related genes. Results: Increasing the Dex concentration was found to reduce cellular viability, with an increase in alkaline phosphatase activity and mineralization. Within the range of Dex concentrations tested in this study, 100 nM of Dex was found to promote the most vigorous differentiation and mineralization of hPDL cells. Dex-induced osteogenic differentiation and mineralization was accompanied by an increase in the level of osteogenic and apoptosis-related genes and a reduction in the level of antiapoptotic genes. The decrease in hPDL cellular viability by glucocorticoid may be explained in part by the increased prevalence of cell apoptosis, as demonstrated by BAX expression and decreased expression of the antiapoptotic gene, Bcl-2. Conclusions: An increase in hPDL cell differentiation rather than cellular viability at an early stage is likely to be a key factor in glucocorticoid induced mineralization. In addition, apoptosis might play an important role in Dex-induced tissue regeneration; however, further study is needed for investigation of the precise mechanism.

• Korean Journal of Veterinary Research
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• v.64 no.1
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• pp.2.1-2.8
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• 2024

This study was performed to assess the antiapoptotic effect of canine platelet-rich plasma (PRP) treated on the canine adipose-derived mesenchymal stem cells (cMSCs) under cold ischemic conditions. The effect of preventing apoptosis of cMSCs was evaluated in the apoptotic condition induced by cold ischemic injury in vitro. To determine the progression of apoptosis, the changes in cell nucleus were observed using 4',6-diamidino-2-phenylindole (DAPI) fluorescence staining. In addition, we examined the mitochondrial membrane potential (MMP) and caspase-3 activity. When the cold hypoxic injury was applied to cMSCs, the apoptotic change was observed by DAPI staining, mitochondrial staining for MMP, and caspase-3 assay. PRP significantly decreased the number of apoptotic cells. Nuclear shrinkage and fragmentation of apoptotic cells in control groups were observed by DAPI staining. The MMP was recovered by the treatment of PRP. In addition, when the luminescence intensity was measured for caspase-3 activity, the value was significantly higher in the PRP treated groups than the control groups. The results of this study showed that the PRP may have a beneficial effect on apoptosis induced by cold ischemic injury.

• 대한생식의학회:학술대회논문집
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• 2005.06a
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• pp.128-128
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• 2005

• Biomedical Science Letters
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• v.20 no.4
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• pp.244-249
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• 2014

Arazyme is a metalloprotease secreted by Aranicola proteolyticus that was previously shown to suppress cytokine expression of keratinocytes and endothelial cells and inhibit histopathological features in an atopic dermatitis-like animal model. However, the regulatory effects of arazyme in other allergic diseases have yet to be elucidated. In this study, we investigated whether arazyme is effective against neutrophil apoptosis in allergic diseases such as allergic rhinitis and asthma. Arazyme inhibited neutrophil apoptosis of normal subjects in a dose-dependent manner. However, the antiapoptotic effect of arazyme was reversed by LY294002, an inhibitor of PI3K, AKTi, an inhibitor of Akt, PD98059, an inhibitor of MEK, and BAY-11-7085, an inhibitor of NF-${\kappa}B$. Arazyme induced activation of NF-${\kappa}B$ via PI3K/Akt/ERK pathway. The anti-apoptotic effect of arazyme is associated with inhibition of cleavage of caspase 3 and caspase 9. Arazyme inhibited constitutive apoptosis of neutrophil in a dose-dependent manner in allergic subjects, and its mechanism was shown to be associated with PI3K/Akt/ERK/NF-${\kappa}B$. The results presented here improve our understanding of neutrophil apoptosis regulation and will facilitate development of drugs for treatment of allergic diseases.

• Journal of the Korean Wood Science and Technology
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• v.42 no.5
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• pp.523-532
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• 2014

This study was done to evaluate the antioxidant effect of oak hot water extracts on the oxidative stress induced by reactive oxygen species (ROS). The cytotoxicity of $H_2O_2$-induced oxidative stress was performed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay for the cell viability according to the dose-dependent treatment. Oak extracts demonstrated a dose-dependent ability to inhibit $H_2O_2$-induced apoptosis in cultured tenofibroblasts, as assessed by MTT assay and FACS analysis. $H_2O_2$ increased the phosphorylation of extracellular regulated kinase1/2 (ERK1/2) and of c-Jun N-terminal kinase (JNK) and the production of reactive oxygen species (ROS). In contrast, treatment with oak extracts was decreased this activation of ERK1/2 and JNK, as confirmed by western blot analysis, and reduced the production of ROS, as verified by fluorescent microscopic and flow cytometry (FACS) analyses. These findings suggest that oak extracts, by suppressing JNK, ERK1/2, and intracellular ROS production, have a concentration-dependent antiapoptotic effect on achilles tenofibroblasts exposed to an oxidative stressor, and may have therapeutic potential.

• Herbal Formula Science
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• v.31 no.3
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• pp.183-191
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• 2023

Objective : UVB damages skin health by causing skin redness and intense inflammation, sunburn, and skin cancer. Paeoniae Radix Alba has been used to relieve gynecological symptoms, muscle spasms, and skin ailments. This study was conducted to confirm whether it has a protective effect against UVB photodamage. Methods : Ethanol extract of Paeoniae Radix Alba (PRA) was prepared by extracting 100 g Paeoniae Radix Alba in 1 L of ethanol for 48 h. Apoptosis was monitored by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and expression levels of apoptosis indicator proteins, and tyrosinase activity was measured with a colorimetric commercial kit. Results : In human keratinocyte HaCaT cells, PRA reduced UVB-induced cell death through apoptosis by inhibiting PARP cleavage and caspase-3 and -9. UVB-induced increase in cellular reactive oxygen species (ROS) was suppressed by PRA pretreatment. PRA also showed dose-dependent ABTS and DPPH radical scavenging activities. Furthermore, the inhibitory effect of tyrosinase activity by PRA was confirmed. Conclusion : These results demonstrated the protective role of PRA in UVB photodamage of human keratinocytes, mainly due to its antioxidant and antiapoptotic properties. We also suggest that PRA can be considered as an effective natural agent to prevent skin photodamage.

• Kidney Research and Clinical Practice
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• v.36 no.2
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• pp.145-157
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• 2017

Background: Vitamin D is considered to exert a protective effect on various renal diseases but its underlying molecular mechanism remains poorly understood. This study aimed to determine whether paricalcitol attenuates inflammation and apoptosis during lipopolysaccharide (LPS)-induced renal proximal tubular cell injury through the prostaglandin $E_2$ ($PGE_2$) receptor EP4. Methods: Human renal tubular epithelial (HK-2) cells were pretreated with paricalcitol (2 ng/mL) for 1 hour and exposed to LPS ($1{\mu}g/mL$). The effects of paricalcitol pretreatment in relation to an EP4 blockade using AH-23848 or EP4 small interfering RNA (siRNA) were investigated. Results: The expression of cyclooxygenase-2, $PGE_2$, and EP4 were significantly increased in LPS-exposed HK-2 cells treated with paricalcitol compared with cells exposed to LPS only. Paricalcitol prevented cell death induced by LPS exposure, and the cotreatment of AH-23848 or EP4 siRNA offset these cell-protective effects. The phosphorylation and nuclear translocation of p65 nuclear factor-kappaB ($NF-{\kappa}B$) were decreased and the phosphorylation of Akt was increased in LPS-exposed cells with paricalcitol treatment. AH-23848 or EP4 siRNA inhibited the suppressive effects of paricalcitol on p65 $NF-{\kappa}B$ nuclear translocation and the activation of Akt. The production of proinflammatory cytokines and the number of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive cells were attenuated by paricalcitol in LPS exposed HK-2 cells. The cotreatment with an EP4 antagonist abolished these anti-inflammatory and antiapoptotic effects. Conclusion: EP4 plays a pivotal role in anti-inflammatory and antiapoptotic effects through Akt and $NF-{\kappa}B$ signaling after paricalcitol pretreatment in LPS-induced renal proximal tubule cell injury.

• Biomolecules & Therapeutics
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• v.24 no.4
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• pp.426-432
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• 2016

Age-related rotator cuff tendon degeneration is related to tenofibroblast apoptosis. Anthocyanins reduce oxidative stress-induced apoptotic cell death in tenofibroblasts. The current study investigated the presence of cell protective effects in cyanidin and delphinidin, the most common aglycon forms of anthocyanins. We determined whether these anthocyanidins have antiapoptotic and antinecrotic effects in tenofibroblasts exposed to $H_2O_2$, and evaluated their biomolecular mechanisms. Both cyanidin and delphinidin inhibited $H_2O_2$-induced apoptosis in a dose-dependent manner. However, at concentrations of $100{\mu}g/ml$ or greater, delphinidin showed cytotoxicity against tenofibroblasts and a decreased antinecrotic effect. Cyanidin and delphinidin both showed inhibitory effects on the $H_2O_2$-induced increase in intracellular ROS formation and the activation of ERK1/2 and JNK. In conclusion, both cyanidin and delphinidin have cytoprotective effects on cultured tenofibroblasts exposed to $H_2O_2$. These results suggest that cyanidin and delphinidin are both beneficial for the treatment of oxidative stress-mediated tenofibroblast cell death, but their working concentrations are different.

• The Journal of Korean Medicine
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• v.30 no.4
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• pp.79-92
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• 2009

Objectives: The aim of the present study was to explore the neuroprotective effect and the possible mechanism of the PD-1 extracts on 1-methyl-4-phenyl-1,2,3,6-tetrahydrophridine (MPTP)-lesioned C57BL/6 mouse model of Parkinson's disease (PD). Methods: The mice were supplemented (or not) with 50 or 100 mg/kg/day of PD-1 for 2 weeks, after which MPTP was injected intraperitoneally. We observed that daily administration of PD-1 prevented MPTP-induced depletion of striatal DA, and maintained striatal and nigral tyrosine hydroxylase (TH) protein levels. Results: Our results demonstrated that mice treated with PD-1 prior to MPTP administration showed more abundant TH-immunopositive (TH-ir) fibers and neurons than mice given only MPTP, indicating that PD-1 protects dopaminergic striatal fibers and nigral neurons from MPTP insults. Possible neuroprotective effect of PD-1 was further studied by the detection of antiapoptotic protein (bcl-2) and proapoptotic protein (Bax). In this assay, MPTP elevated the Bax protein and decreased the bcl-2 protein, while these expressions were prevented by PD-1 pre-treatment. Conclusions: The present results suggest that PD-1 is able to protect dopaminergic neurons from MPTP-induced neuronal injury with anti-apoptotic activity being one of the possible mechanisms.

• The Korea Journal of Herbology
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• v.38 no.1
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• pp.21-30
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• 2023

Objective : Gardeniae Fructus (GF) has bitter and cold nature. Thus, it has been traditionally prescribed in processed form roasted with ginger juice for patients with a weak stomach. This study investigated the effects of processed GF in tert-butyl hydroperoxide (tBHP)-treated gastric epithelial cells. Methods : Processed GF was made by applying 40% ginger juice or 10% ethanol for 24 h and then roasting at 150℃ for 5 minutes. Apoptosis was determined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Mitochondrial membrane potential (MMP) was monitored by flow cytometry using the membrane permeable fluorescent dye Rh123. Protein expression was measured by Western blot analysis. Results : Cell viability was reduced by tBHP and restored by ethanol extract of GF (GFE). In the TUNEL assay, it was found that cell death by tBHP was due to apoptosis, and GFE had an anti-apoptotic effect. Processed GF roasted with ginger juice showed the best anti-apoptotic effect. Processed GF also inhibited MMP loss and restored tBHP-induced changes in expression levels of apoptosis-related proteins. Increased ROS production and GSH depletion after tBHP treatment were significantly reduced by processed GF. In addition, tBHP-induced activation of mitogen-activated protein kinase (MAPK) was inhibited by processed GF. Conclusion : These results demonstrate that the processed GF is able to protect gastric epithelial cells from oxidative stress-induced cell death with antiapoptotic and antioxidant activity. In addition, it shows that the processing of GF, which have been traditionally used for gastrointestinal protection, partially have scientific validity.