• Title/Summary/Keyword: $\beta-cell$ function

Search Result 346, Processing Time 0.023 seconds

Separation of $H_2$/$N_2$ Gas Mixture by PTMSP-PEI and PDMS-PEI Composite Membranes (PTMSP-PEI와 PDMS-PEI 복합막에 의한 수소/질소 혼합기체 분리)

  • 강태범;조성혜;이현경
    • Membrane Journal
    • /
    • v.13 no.4
    • /
    • pp.291-299
    • /
    • 2003
  • Polymer membranes such as poly(1-trimethylsilyl-1-propyne)-polyetherimide (PTMSP-PEI) and poly(dimethylsiloxane)- polyetherimide (PDMS-PEI) composite membrane were prepared by solution casting method. To investigate the characteristics of these membranes, the analytical methods such as FT-IR, $^1H-NMR,$ DSC, TGA, GPC, and SEM have been utilized. The number-average (equation omitted) and weight-average (equation omitted) molecular weight of PTMSP were 477,920 and 673,329 respectively. The glass transition temperature ($T_g$) of PTMSP was $224^{\circ}C.$ The separation of the gas mixture ($H_2/N_2$) through the composite membranes were studied as a function of pressure. The separation factor (${\alpha}, {\beta},$ quation omitted) of the composite membranes used in this work increased as the pressure of permeation cell increased. The real separation factor (${\alpha}$), head separation factor (${\beta}$), and tail separation factor (equation omitted) of PTMSP-PEI composite membrane were 2.28, 1.17, and 1.96 respectively at ${\Delta}P$ 30psi and $25^{\circ}C.$ (${\alpha}, {\beta}$ and equation omitted of PDMS-PEI composite membrane were 3.70, 1.53, and 2.42 respectively at ${\Delta}P$ 30psi and $25^{\circ}C$.

CCAAT/enhancer binding protein β Induces Post-Switched B Cells to Produce Blimp1 and Differentiate into Plasma Cells

  • Geonhee Lee;Eunkyeong Jang;Jeehee Youn
    • IMMUNE NETWORK
    • /
    • v.20 no.5
    • /
    • pp.42.1-42.10
    • /
    • 2020
  • Long-lasting post-switched plasma cells (PCs) arise mainly from germinal center (GC) reactions, but little is known about the mechanism by which GC B cells differentiate into PCs. Based on our observation that the expression of the transcription factor CCAAT/enhancer binding protein β (C/EPBβ) is associated with the emergence of post-switched PCs, we enquired whether a cell-autonomous function of C/EPBβ is involved in the program for PC development. To address this, we generated C/EPBβ-deficient mice in which the Cebpb locus was specifically deleted in B cells after transcription of the Ig γ1 constant gene segment (Cγ1). In response to in vitro stimulation, B cells from these Cebpbfl/flCγ1Cre/+ mice had defects in the induction of B lymphocyte-induced maturation protein 1 (Blimp1) and the formation of IgG1+ PCs, but not in proliferation and survival. At steady state, the Cebpbfl/flCγ1Cre/+ mice had reduced serum IgG1 titers but normal IgG2c and IgM titers. Moreover, upon immunization with T-dependent Ag, the mice produced reduced levels of Ag-specific IgG1 Ab, and were defective in the production of Ag-specific IgG1 Ab-secreting cells. These results suggest that a cell-autonomous function of C/EPBβ is crucial for differentiation of post-switched GC B cells into PCs through a Blimp1-dependent pathway.

Interactions between Collagen IV and Collagen-Binding Integrins in Renal Cell Repair after Sublethal Injury

  • Nony, Paul A,;Schnellmann, Rick G.
    • Proceedings of the Korea Environmental Mutagen Society Conference
    • /
    • 2002.11a
    • /
    • pp.80-88
    • /
    • 2002
  • Recent studies demonstrate that collagen IV selectively pro-motes the repair of physiological processes in sublethally injured renal proximal tubular ceils (RPTC). We sought to further define the mechanisms of cell repair by measuring the effects of toxicant injury and stimulation of repair by L-ascorbic acid-2-phosphate (AscP), exogenous collagen IV, or function-stimulating integrin antibodies on the expression and subcellular localization of collagen-binding integrins (CBI) in RPTC. Expression of CBI subunits ${\alpha}_1$, ${\alpha}_2$, and ${\beta}_1$ in RPTC was not altered on day 1 after sublethal injury by S-(1,2-dichlorovinyl)-L-cysteine (DCVC). On day 6, expression of ${\alpha}_1$ and ${\beta}_1$ subunits remained unchanged, whereas a 2.2-fold increase in ${\alpha}_2$ expression was evident in injured RPTC. CBI localization in control RPTC was limited exclusively to the basal membrane. On day 1 after injury, RPTC exhibited a marked inhibition of active $Na^+$ transport and a loss of cell polarity characterized by a decrease in basal CBI localization and the appearance of CBI on the apical membrane. On day 6 after injury, RPTC still exhibited marked inhibition of active $Na^+$ transport and localization of CBI to the apical membrane. However, DCVC-injured RPTC cultured in pharmacological concentrations of AscP (500 ${\mu}$M)or exogenous collagen IV (50 ${\mu}$g/ml) exhibited an increase inactive $Na^+$ transport, relocalization of CBI to the basal membrane, and the disappearance of CBI from the apical membrane on day 6. Function-stimulating antibodies to CBI ${\beta}_1$ did not promote basal relocalization of CBI despite stimulating the repair of $Na^+$/$K^+$-ATPase activity on day 6 after injury. These data demonstrate that DCVC disrupts integrin localization and that physiological repair stimulated by AscP or collagen IV is associated with the basal relocalization of CBI in DCVC-injured RPTC. These data also suggest that CBI-mediated repair of physiological functions may occur independently of integrin relocalization.

  • PDF

The Potato Transcriptional Co-activator StMBF1 Is Up-regulated in Response to Oxidative Stress and Interacts with the TATA-box Binding Protein

  • Arce, Debora Pamela;Tonon, Claudia;Zanetti, Maria Eugenia;Godoy, Andrea Veronica;Hirose, Susumu;Casalongue, Claudia Anahi
    • BMB Reports
    • /
    • v.39 no.4
    • /
    • pp.355-360
    • /
    • 2006
  • To gain a better understanding on the function of the potato Solanum tuberosum Multiprotein Bridging Factor 1 protein (StMBF1) its interaction with the TATA box binding protein (TBP) was demonstrated. In addition we reported that StMBF1 rescues the yeast mbf1 mutant phenotype, indicating its role as a plant co-activator. These data reinforce the hypothesis that MBF1 function is also conserved among non closely related plant species. In addition, measurement of StMBF1 protein level by Western blot using anti-StMBF1 antibodies indicated that the protein level increased upon $H_2O_2$ and heat shock treatments. However, the potato $\beta$-1,3-glucanase protein level was not changed under the same experimental conditions. These data indicate that StMBF1 participates in the cell stress response against oxidative stress allowing us to suggest that MBF1 genes from different plant groups may share similar functions.

Hangambujeongsan or Kangai Fuzheng Powder shows the anti-cancer effect by enhancing macrophage activation

  • Yang, Wan-Quan;Han, Hyung Soo
    • The Korea Journal of Herbology
    • /
    • v.29 no.1
    • /
    • pp.1-6
    • /
    • 2014
  • Objectives : Many of currently used anti-cancer drugs were developed to target cell death mechanisms and had serious side effects by causing damage to normal cells. Hangambujeongsan or Kangai Fuzheng Powder was a mixture based on the traditional Chinese medicine. It had been used in the local Chinese hospitals to treat cancer patients for decades and had shown a certain level of beneficial effects without major toxic effects. But its mechanism of action had not been elucidated yet. Thus this study aimed to investigate the effects of Kangai Fuzheng Powder in an in vitro experiment. Methods : Cancer lines or RAW264.7 mouse macrophage cells were treated with Kangai Fuzheng Powder. Cell viability was measured by MTT assay, and morphological observation was also performed. Gene expression of cytokines in macrophages was determined by real-time polymerase chain reaction. Phagocytic function assay was also performed in macrophage cells. Results : Kangai Fuzheng Powder had no direct detrimental effect on cancer cells. When macrophages were co-cultured with cancer cells, Kangai Fuzheng Powder had toxic effect on cancer cells. After exposing macrophages to Kangai Fuzheng Powder, macrophages transformed into activated form and the mRNA level of tumor necrosis factor-alpha, interleukin-1beta, interleukin-6, interleukin-10 and monocyte chemotactic protein-1 was significantly enhanced. Phagocytic activity of macrophages was dramatically potentiated. Conclusions : We demonstrated that anti-cancer effect of Kangai Fuzheng Powder was related to activation of macrophages including enhanced cytokine production and phagocytic function.

Effect of Sparassis crispa Extracts on Immune Cell Activation and Tumor Growth Inhibition (꽃송이버섯(Sparassis crispa) 추출물의 면역세포 활성화 및 항암 효과)

  • Kim, In-Kyu;Yun, Young Chul;Shin, Yong Chul;Yoo, Jiyun
    • Journal of Life Science
    • /
    • v.23 no.8
    • /
    • pp.984-988
    • /
    • 2013
  • Sparassis crispa is an edible mushroom with medicinal properties that contains more than 40% ${\beta}$-glucan. The role of S. crispa in regulating the functional activation of macrophages has yet to be fully elucidated. The objective of this study was to investigate the molecular mechanism underlying the immune-stimulatory function of S. crispa soluble ${\beta}$-glucan and extracts on macrophages. In this study, we showed that S. crispa soluble ${\beta}$-glucan was able to stimulate TNF-${\alpha}$ and IL-$1{\beta}$ production through NF-${\kappa}B$ activation in Raw 264.7 cells. We also showed that S. crispa extracts could not only enhance TNF-${\alpha}$ production in Raw 264.7 cells, but also suppress tumor growth in vivo. All of our results suggest that S. crispa could be developed as a promising immunostimulatory principle, applicable to cancer patients.

Comparison of Cellular Senescence Phenotype in Human Fibroblasts from New-born and Aged Donors. (신생아와 노인 유래 섬유아세포의 노화과정에서의 세포학적 성질의 비교)

  • Yi, Hye-Won;Hwang, Eun-Seong
    • Journal of Life Science
    • /
    • v.18 no.3
    • /
    • pp.344-349
    • /
    • 2008
  • Normal somatic cells proliferate for a limited number of doublings in culture and then enter an irreversible growth-arrest state called replicative senescence. Replicative senescence has been believed a reason for the limited cellular turnover and deterioration of tissue function in aged animals. However, there is no experimental evidence supporting this assumption. Furthermore, cells from aged person have been poorly characterized with an exception of the cases of T cells. In this study, we examined cell biological changes occurring in replicative senescence of fibroblast strains originated from a new-born (NHF-NB) and a 87 year old man (NHF-87). NHF-87 (and the cells from a 75-year old) proliferated to smaller population doublings and with longer doubling times than NHF-NB did. At early passages, NHF-87 exhibited a low senescence-associated ${\beta}-Gal$ (SA ${\beta}-Gal$) activity and lipofuscin level, typical markers for cellular senescence. Furthermore, they maintained low levels of lysosome and reactive oxygen species (ROS). All of these levels increased dramatically in the late passage NHF-87 quite similarly as those in the late passaged NHF-NB did. These results indicate that most cells originated from the aged maintain a phenotype of the cells originated from new-born donors and undergo replicative senescence with the same kinetics as that of the cells from new-born. It is also indicated that not SA ${\beta}-gal$ activity but cell proliferation rate may be qualified as a biomarker for cells aged in vivo.

Effects of Plant Water Extract Codonopsis Lanceolatae on Mouse Immune Cell Activation Ex Vivo (더덕 물 추출물의 경구 투여가 마우스 면역 세포 활성에 미치는 효과)

  • Ryu, Hye-Sook;Kim, Kyoung-Ok;Kim, Hyun-Sook
    • Journal of Nutrition and Health
    • /
    • v.42 no.3
    • /
    • pp.207-212
    • /
    • 2009
  • Codonopsis lanceolatae has been used as one of the traditional remedies as well as food source. However, few studies on their immunomodulating effects have been reported. We previously reported that ex vivo supplementation of Codonopsis lanceolatae water extracts enhanced splenocyte proliferation compared to the control group. In order to elucidate its ex vivo effect, six to seven week old balb/c mice were fed ad libitum on a chow diet and water extracts of Codonopsis lanceolatae were orally administrated every other day for four weeks at two different concentrations (50 and 500 mg/kg B.W). After preparing the single cell suspension, the proliferation of splenocytes was determined by MTT (3- [4,5-dimethylthiazol-2-y] -2,5-diphenyl terazolium bromide) assay. The production of cytokine (IL-1${\beta}$, IL-6, TNF-${\alpha}$), secreted by macrophages stimulated with LPS or not, was detected by ELISA assay using a cytokine kit. After 48 hrs of incubation with the mitogen (ConA or LPS) stimulation, the mice splenocyte proliferation in experimental group was statistically increased at two different concentrations than that in control group. The cytokines production was more significantly enhanced at the lower supplementation (500 mg/kg B.W.) group rather than higher concentration (500 mg/kg B.W.) compared to the control group. The results of this study may suggest that the supplementation of water extract of plant mixture could regulate the immune function by increasing the splenocyte proliferation and enhance the immune function through regulating cytokine production capacity by activated macrophages in mice.

Effect of Samryungbaikchul-san on Astrocyte Activation and Apoptosis in Mouse Model of Alzheimer Disease (삼령백출산(蔘笭白朮散)이 Alzheimer's Disease 동물모델의 Astrocyte 활성화 및 Apoptosis에 미치는 영향)

  • Lee, Sang-Ryong
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.23 no.2
    • /
    • pp.374-380
    • /
    • 2009
  • Samryungbaikchul-san(SRBCS) has been used in oriental medicine for the treatments of gastrointestinal and neurological disorders. Here, potential protective function of SRBCS was investigated in neural tissues in Alzheimer's disease(AD) mouse model. In primary cultured cells from the spinal cord of newborn rats, treatment of ${\beta}$-amyloid peptide elevated cell counts positive to glial fibrillary acidic protein(GFAP) or caspase 3 immunoreactivity, but the co-treatment of SRBCS reduced positive cell counts. In vivo administration of scopolamine, an inhibitor of muscarinic receptor, resulted in increases in the number of glial fibrillary acidic protein(GFAP) and caspase 3-positive cells in hippocampal subfields, which was then decreased by the treatment of SRBCS or acetylcholinesterase inhibitor galathamine. The present data suggest that SRBCS may play a protective role in damaged neural tissues caused by scopolamine treatments in mice.

EFFECT OF NERVE GROWTH FACTOR GENE INJECTION ON THE NERVE REGENERATION IN RAT LINGUAL NERVE CRUSH-INJURY MODEL (백서 설신경 압박손상모델에서 신경성장인자 유전자 주입이 신경재생에 미치는 영향)

  • Gao, En-Feng;Chung, Hun-Jong;Ahn, Kang-Min;Kim, Soung-Min;Kim, Yun-Hee;Jahng, Jeong-Won;Lee, Jong-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.28 no.5
    • /
    • pp.375-395
    • /
    • 2006
  • Purpose: Lingual nerve (LN) damage may be caused by either tumor resection or injury such as wisdom tooth extraction, Although autologous nerve graft is sometimes used to repair the damaged nerve, it has the disadvantage of necessity of another operation for nerve harvesting. Moreover, the results of nerve grafting is not satisfactory. The nerve growth factor (NGF) is well-known to play a critical role in peripheral nerve regeneration and its local delivery to the injured nerve has been continuously tried to enhance nerve regeneration. However, its application has limitations like repeated administration due to short half life of 30 minutes and an in vivo delivery model must allow for direct and local delivery. The aim of this study was to construct a well-functioning $rhNGF-{\beta}$ adenovirus for the ultimate development of improved method to promote peripheral nerve regeneration with enhanced and extended secretion of hNGF from the injured nerve by injecting $rhNGF-{\beta}$ gene directly into crush-injured LN in rat model. Materials and Methods: $hNGF-{\beta}$ gene was prepared from fetal brain cDNA library and cloned into E1/E3 deleted adenoviral vector which contains green fluorescence protein (GFP) gene as a reporter. After large scale production and purification of $rhNGF-{\beta}$ adenovirus, transfection efficiency and its expression at various cells (primary cultured Schwann cells, HEK293 cells, Schwann cell lines, NIH3T3 and CRH cells) were evaluated by fluorescent microscopy, RT-PCR, ELISA, immunocytochemistry. Furthermore, the function of rhNGF-beta, which was secreted from various cells infected with $rhNGF-{\beta}$ adenovirus, was evaluated using neuritogenesis of PC-12 cells. For in vivo evaluation of efficacy of $rhNGF-{\beta}$ adenovirus, the LNs of 8-week old rats were exposed and crush-injured with a small hemostat for 10 seconds. After the injury, $rhNGF-{\beta}$ adenovirus($2{\mu}l,\;1.5{\times}10^{11}pfu$) or saline was administered into the crushed site in the experimental (n=24) and the control group (n=24), respectively. Sham operation of another group of rats (n=9) was performed without administration of either saline or adenovirus. The taste recovery and the change of fungiform papilla were studied at 1, 2, 3 and 4 weeks. Each of the 6 animals was tested with different solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) by two-bottle test paradigm and the number of papilla was counted using SEM picture of tongue dorsum. LN was explored at the same interval as taste study and evaluated electro-physiologically (peak voltage and nerve conduction velocity) and histomorphometrically (axon count, myelin thickness). Results: The recombinant adenovirus vector carrying $rhNGF-{\beta}$ was constructed and confirmed by restriction endonuclease analysis and DNA sequence analysis. GFP expression was observed in 90% of $rhNGF-{\beta}$ adenovirus infected cells compared with uninfected cells. Total mRNA isolated from $rhNGF-{\beta}$ adenovirus infected cells showed strong RT-PCR band, however uninfected or LacZ recombinant adenovirus infected cells did not. NGF quantification by ELISA showed a maximal release of $18865.4{\pm}310.9pg/ml$ NGF at the 4th day and stably continued till 14 days by $rhNGF-{\beta}$ adenovirus infected Schwann cells. PC-12 cells exposed to media with $rhNGF-{\beta}$ adenovirus infected Schwann cell revealed at the same level of neurite-extension as the commercial NGF did. $rhNGF-{\beta}$ adenovirus injected experimental groups in comparison to the control group exhibited different taste preference ratio. Salty, sweet and sour taste preference ratio were significantly different after 2 weeks from the beginning of the experiment, which were similar to the sham group, but not to the control group.