• The korean journal of orthodontics
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• 제33권6호
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• pp.453-463
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• 2003

Mammalian cell is critically dependent on a continuous supply of oxygen. Even brief periods of oxygen deprivation can result in profound cellular damage. The aim of this study was to examine the possible mechanism of apoptosis in response to hypoxia in MC3T3E1 osteoblasts. MC3T3El osteoblasts under hypoxic conditions ($2\%$ oxygen) resulted in apoptosis in a time-dependent manner, determined by DNA fragmentation assay and nuclear morphology, stained with fluorescent dye (Hoechst 33258) Pretreatment with Z-VAD-FMK, a pancaspase inhibitor, or Z-DEVD-CHO, a specific caspase-3 inhibitor, suppressed the DNA ladder in response to hypoxia in a concentration dependent manner. An increase in caspase-3-like protease (DEVDase) activity was observed during apoptosis, but no caspase-l activity (YVADase) was detected. To confirm what caspases were involved in apoptosis, western blot analysis was performed using an anticaspase-3 or 6 antibody. The 17-kDa protein, that corresponds to the active products of caspase-3 and the 20-kDa protein of the active protein of caspase-6 were generated in hypoxia-challenged lysates, in which the full length forms of caspase-3 and 6 were evident. With a time course similar to caspase-3 and 6 activation, hypoxic stress also caused the cleavage of Lamin A, typical of caspase-6 activity. In addition, the hypoxic stress elicited the release of cytochrome c into the cytosol during apoptosis. These findings suggested that the activation of caspases accompanied by a cytochrome c release in response to hypoxia was involved in apoptotic cell death in MC3T3E1 osteoblasts.

• The korean journal of orthodontics
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• 제27권6호
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• pp.929-941
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• 1997

Optimal force for orthodontic treatment is the force that produces a rapid rate of tooth movement without discomfort to the Patient or ensuing tissue damage. Recently considerable interest has been generated in the application of magnets as a way to obtain an optimal force. The purpose of the present study was to investigate the effect of static magnetic fields of Sm-Co magnets on molecular and cellular activities. The distance of erythrocyte sedimentation was measured directly, and the activities and the syntheses of $Fe^{2+}$-related enzymes (catalase and NO synthase) and non $Fe^{2+}$-related enzyme (lactic dehydrogenase) were assayed by the spectrophotometer. The growth and the proliferation of osteoblast-like cells $MC_3T_3-E_1$ were determined by the crystal violet staining and the ${^3}H$-thymidine incorporation. The erythrocytes were exposed to the pole face flux density of 1,400 G (gauss), and the enzymes and osteoblast-like cells $MC_{3}T_3-E_1$ were exposed to the flux density of 7,000 G. The results obtained were as follows: 1. The distance of sedimentation of erythrocyte was not affected by the static magnetic fields. 2. The activities of catalase and lactic dehydrogenase were not affected by the static magnetic fields. 3. The intracellular syntheses of NO synthase and lactic dehydrogenase were not affected by the static magnetic fields. 4. The growth and the proliferation of cultured osteoblast-like cells $MC_{3}T_3-E_1$ were not affected by the static magnetic fields. These results suggested that the molecular and cellular activities were not significantly influenced by the static magnetic fields.

• Journal of the Korean Society of Food Science and Nutrition
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• 제43권2호
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• pp.200-206
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• 2014

We investigated the in vitro and in vivo anti-obesity effects of extracts from young Akebia quinata D. leaves, including hot water (AQH) and 80% ethanol (AQE) extracts. The inhibitory effects of AQH and AQE on lipid accumulation in 3T3-L1 cells were examined by Oil Red O staining. Compared to control, lipid accumulation was significantly reduced by 18.3% with the treatment upon AQE at a concentration of $5{\mu}g/mL$. The levels of intracellular triglycerides and free glycerol were also reduced by 52.8% and 9.1% at the same concentration of AQE. The in vivo anti-obesity effect of AQE was evaluated in terms of body and white adipose tissue weights in ICR mice. Experimental groups were divided into the following five groups: normal diet (ND), high fat diet (HFD), high fat diet with 60 mg/kg/day of Orlistat (HFD-RF), high fat diet with 200 mg/kg/day of AQE (HFD-AL), and high fat diet with 600 mg/kg/day of AQE (HFD-AH). Feeding of HFD for eight weeks resulted in significant increases in body weight as well as weight gain compared to the ND group. HFD-AH group showed reduced body weight, weight gain, epididymal white adipose tissue weight, and perirenal white adipose weight as compared to the HFD group. These results indicate that AQE supplementation might have beneficial effects on anti-obesity by inhibiting lipid accumulation.

• Journal of Life Science
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• 제22권10호
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• pp.1415-1419
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• 2012

Thymosin ${\beta}4$ ($T{\beta}4$) has been reported to be overexpressed in CD133-positive colorectal cancer stem cells. We analyzed the relationship between $T{\beta}4$ and CD133-positive stem cells in normal stomach by examining the expression patterns of $T{\beta}4$ and CD133 in normal stomach tissues by immunohistochemical staining; co-localization of $T{\beta}4$ and CD133 was studied by immunofluorescence and confocal laser-scanning microscopy. Both $T{\beta}4$ and CD133 were expressed in stomach glands and showed similar expression patterns. Immunofluorescence staining of $T{\beta}4$ and CD133 showed that the expression of $T{\beta}4$ and CD133 was co-localized. In summary, both $T{\beta}4$ and CD133 were expressed in glands of normal stomachs and expression patterns were co-localized. These data suggest that $T{\beta}4$ expression is strongly related to CD133 expression.

• Korean Journal of Transplantation
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• 제31권4호
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• pp.157-169
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• 2017

Regulatory T cells (Treg) naturally rein in immune attacks, and they can inhibit rejection of transplanted organs and even reverse the progression of autoimmune diseases in mice. The initial safety trials of Treg against graft-versus-host disease (GVHD) provided evidence that the adoptive transfer of Treg is safe and capable of limiting disease progression. Supported by such evidence, numerous clinical trials have been actively investigating the efficacy of Treg targeting autoimmune diseases, type I diabetes, and organ transplant rejection, including kidney and liver. The limited quantity of Treg cells harvested from peripheral blood and subsequent in vitro culture have posed a great challenge to large-scale clinical application of Treg; nevertheless, the concept of CAR (chimeric antigen receptor)-Treg has emerged as a potential resolution to the problem. Recently, two CAR-T therapies, tisagenlecleucel and axicabtagene ciloleucel, were approved by the US FDA for the treatment of refractory or recurrent acute lymhoblastic leukemia. This approval could serve as a guideline for the production protocols for other genetically engineered T cells for clinical use as well. The phase I and II clinical trials of these agents has demonstrated that genetically engineered and antigen-targeting T cells are safe and efficacious in humans. In conclusion, both the promising results of Treg cell therapy from the clinical studies and the recent FDA approval of CAR-T therapies are paving the way for CAR-Treg therapy in clinical use.

• Applied Biological Chemistry
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• 제45권1호
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• pp.42-46
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• 2002

Effects of the water extract from Kalopanax pictus NAKAI on insulin-like action and glucose uptake in 3T3-L1 cells were investigated. The bark of K. pictus NAKAI was treated with hot water and the extract was freeze-dried. Total extract of K. pictus NAKAI was fractionated into 6 fractions with increasing gradients from 0 to 100% MeOH on Amberlite XDA-4. Treatment of 3T3-L1 fibroblasts with 1 ${\mu}g/ml$ and 10 ${\mu}g/ml$ of K. pictus NAKAI total extracts significantly increased the differentiation of the cells. When co-treated with inducers such a dexamethasone, 1-methyl-3-isobutylxanthine and insulin, the differentiation was increased at 1 ${\mu}g/ml$ of total extract, but not at 10 ${\mu}g/ml$. In 3T3-L1 adipocytes, glucose uptake was increased by 3.3 times with addition of 0.3 and 3 ${\mu}g/ml$ of Fr. 1 (0-10% MeOH) and Fr. 3 (30% MeOH) at 3 ng/ml insulin. In conclusion, K. pictus NAKAI contains such compounds that play a role of insulin-like action and insulin sensitizer.

• Journal of Life Science
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• 제32권10호
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• pp.762-770
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• 2022

Hyperglycemia in type 2 diabetes can be alleviated by promoting cellular glucose uptake. Betulinic acid (3β,-3-hydroxy-lup-20(29)-en-28-oic acid) is a pentacyclic lupane-type triterpenoid compound. Although there have been studies on the antidiabetic activity of betulinic acid, studies on cellular glucose uptake are lacking. We investigated the effects of betulinic acid on glucose uptake and its mechanism of action in 3T3-L1 adipocytes. Betulinic acid significantly stimulated glucose uptake in 3T3-L1 adipocytes by increasing the phosphorylation of the insulin receptor substrate 1-tyrosine (IRS-1tyr) in the insulin signaling pathway, which in turn stimulated the activation of phosphoinositide 3-kinase (PI3K) and the phosphorylation of protein kinase B (Akt). The activation of PI3K and Akt by betulinic acid translocated glucose transporter 4 to the plasma membrane (PM-GLUT4), thereby increasing the expression of PM-GLUT4 and thus stimulating cellular glucose uptake. Betulinic acid also significantly increased the phosphorylation/activation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase. The activation of PI3K and AMPK by betulinic acid was confirmed using the PI3K inhibitor wortmannin and the AMPK inhibitor compound C. The increase in glucose uptake induced by betulinic acid was significantly decreased by wortmannin and compound C in the 3T3-L1 adipocytes. These results suggest that betulinic acid stimulates glucose uptake by activating PI3K and AMPK in 3T3-L1 adipocytes.

• Journal of the Society of Cosmetic Scientists of Korea
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• 제43권2호
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• pp.87-92
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• 2017

In this study, we investigated the effect of Petasites japonicus extract on the cytotoxicity and cytoprotective effects against cadmium for cosmetics use. We measured the protein expression of apoptosis regulatory factor (Bcl-2 and procaspase-3) after treatment of Petasites japonicus extract in the cadmium-induced keratinocyte. As a result, high cell viabilities above 98% were observed in the all treated concentrations except at $200{\mu}g/mL$ of Petasites japonicus extract in keratinocytes with cadmium-induced damages. In keratinocytes with cadmium-induced damages, Bcl-2 and procaspase-3 protein expression increased in the experimental group treated with Petasites japonicus extract. Also HaCaT cells resulted in cleavage of PARP protein at 12 h post-cadmium exposure. Western blot analysis and relative density of the bands suggested that pretreatment of cells with Petasites japonicus extract inhibited cadmium-mediated cleavage of PARP. These results suggest that Petasites japonicus extract can be used as the cosmetic ingredients for cytoprotective effect.

• The Journal of Natural Sciences
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• 제15권1호
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• pp.89-95
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• 2005

JSRV, which causes sheep lung cancer, is known to have the transforming activity of NIH3T3 cells. Especially Envelope protein of this virus has the transforming activity to NIH3T3. To know the effects on the transcriptional activity of transcription factors by this viral protein transient transfection was performed by using the luciferase reporter system. The result showed that JSRV Envelope protein increased the transcriptional activity of NF-kB and AP-1.

• Parasites, Hosts and Diseases
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• 제29권4호
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• pp.381-388
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• 1991

Trichomonas vaginalis is a parasitic nagellate in the urogenital tract of human. Innate cytotonicity of macrophages against T. vaginalis has been recognized, but any report on the cytotoxicity of Iymphokine-activated macrophages to T vaginalis is not yet available. The present study aimed to elucidate the Iymphokine-activated cell mediated cytotoxic effect against T. vaginalis by mouse peritoneal macrophages. Cytotoxicity was measured by counting the release of $^3H-thymidine$ from prelabeled protozoa, and tested in U-bottom microtiter plates. Nitrite concentration in culture supernatants was measured by standard Griess reaction. The results obtained are as follows: 1, The cytotoxicity of macrophages was increased by addition of rIL-2 or $rIFN-{\gamma}$$. 2, Cytotoxicity of macrophages was reduced by addition of rIL-4 to rOM-CSV, rIL-2 or $rIFN-{\gamma}$. 3. Crude Iymphokine mixed with anti-lL-2 decreased the cytotoxity of macrophages. 4. In case of macrophages cultured with $rIFN-{\gamma}$ or rIL-4, the concentration of nitrite was related with cytotokity of macrophages against T. vaginalis, but the cytotoxicity of macrophages cultured with rIL-2 and $rIFN-{\gamma}$ was decreased in spite of its high production of llitrite. From the results obtained, it is assumed that rIL-2 and $rIFN-{\gamma}$ enhance the cytotoxicity of macrophages while rIL-4 inhibits the cytotoxicity against T. vaginalis, and that the production of nitrite does not relate with the cytotoxicity of macrophages, but nitric oxide may play a role as an inhibitory factor on the proliferation of T. vaginalis.