• Title/Summary/Keyword: Beta cell

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Production of Poly-$\beta$-hydroxybutyrate and Poly-$\beta$-(hydroxybutyrate-co-hydroxyvalerate) by Fed-batch Culture of Alcaligenes eutrophus (Alcaligenes eutrophus의 유가식 배양에 의한 Poly-$\beta$-hydroxybutyrate 및 Poly-$\beta$-(hydroxybutyrate-co-hydroxyvalerate)의 생산)

  • Choi, Eun-Soo;Lee, In-Young;Kang, Choong-Kyung;Hong, Seung-Suh;Lee, Hyun-Soo
    • Microbiology and Biotechnology Letters
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    • v.23 no.5
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    • pp.588-592
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    • 1995
  • Fed-batch fermentation was used to produce the high concentrations of poly-$\beta $-hydroxybutyrate (PHB) and poly-$\beta $-(hydroxybutyrate-co-hydroxyvalerate) (PHB/V). Specific growth rate ($\mu $), yield of cell from glucose (Y$_{x/s}$) were calculated from the two samples in 3 to 5 hours of interval and they were reflected on the determination of glucose feeding rate to maintain the glucose concentration at around 10 g/l in the culture broth. PHB was accumulated after the nitrogen became limited at 60 g/l of dry cell weight by changing ammonia water to 4N-NaOH solution. As results, the final dry cell weight (DCW) of 170 g/l, PHB of 115 g/l were obtained in 50 hours and the overall productivity was 2.4 g/l$\cdot $h. After PHB accumulation, cosubstrate of glucose and propionic acid (PA) was fed to accumulate PHB/V. But, PA feeding rate was decreased from 3 g/l$\cdot $h to 1 g/l$\cdot $h to prevent PA from accumulating to high level in the broth, which is very inhibitory to the cells. As results, DCW, PHB and PHV were 147.5 g/l, 90 g/l and 8 mole % of hydroxyvalerate, respectively.

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The Signaling Mechanism of TGF-β1 Induced Bovine Mammary Epithelial Cell Apoptosis

  • Di, He-Shuang;Wang, Li-Gang;Wang, Gen-Lin;Zhou, Lei;Yang, Yuan-Yuan
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.3
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    • pp.304-310
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    • 2012
  • The present study showed that Transforming growth factor beta 1 (TGF-${\beta}_1$) can induce apoptosis of bovine mammary epithelial cells. This apoptosis was also observed with phosphorylation of Smad2/3 within 0.5-2 h. Afterwards the signal transferred into the nucleus. Moreover, intracellular free $Ca^{2+}$ concentration was significantly elevated as well as Caspase-3 activated and DNA lysised, thereby inducing the programmed cell death. This signaling pathway of TGF-${\beta}_1$ was blocked by SB-431542 ($10^{-2}{\mu}M$) via inhibiting ALK-5 kinase activity, which thus reversed the anti-proliferation and apoptosis effect of TGF-${\beta}_1$ in mammary epithelial cells. These results indicated that TGF-${\beta}_1$ induced apoptosis of bovine mammary epithelial cells through the ALK-5-Smad2/3 pathway, which plays an important role in inhibiting survival of mammary epithelial cells. Moreover, intracellular $Ca^{2+}$ also played a critical role in TGF-${\beta}_1$-induced cell apoptosis.

Inhibition of Endothelial Cell-dependent Serotonin-induced Contraction of ${\beta}-endorphin$ and Increment of Plasma ${\beta}-endorphin$ of Silver Spike Point Low Frequency Electrical Stimulation (${\beta}-Endorphin$의 내피세포의존성-세로토닌 유도-근 수축 억제와 저빈도-주파수 은침점전자극의 혈장 ${\beta}-endorphin$ 증가)

  • Choi Young-Duk;Lee Joon-Hee;Kim Jung-Hwan
    • The Journal of Korean Physical Therapy
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    • v.16 no.3
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    • pp.22-31
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    • 2004
  • The purpose of this study was to demonstrate the effects of silver spike point (SSP) low frequency electrical stimulation on plasma ${\beta}-endorphin$ activities measured by radio- immunoassay from normal volunteer and the effects of ${\beta}-endorphin$ on 5-hydroxytryptamine (5-HT, serotonin)-induced contraction investigated by isometric tension methode in rats. The current of 3 Hz continue type, but not 100 Hz continue type, of SSP low frequency electrical stimulation significantly increased in plasma ${\beta}-endorphin$ from normal volunteer. The endothelial cell-dependent 5-HT-induced contractions were inhibited by ${\beta}-endorphin$ $1{\mu}M$. These results suggest that the ${\beta}-endorphin$ regulates nociceptive-like substance, such as 5-HT, in part and that the SSP low frequency electrical stimulation, specifically current of low frequency of 3 Hz continue type, significantly increases plasma ${\beta}-endorphin$ from normal volunteer.

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Studies on Adivitie of $\beta$-Glucuronidase and Several Glycosidases of the Castrated Rat Epi-didymis Treated with Testosterone and Dibutyryl cAMP and the Cell Types of Epididymal Epithelium (Testosterone과 dibutyryl cyclic AMP가 거세한 흰쥐 부정소의 $\beta$ -glucosidase와 몇가지 glycosidase 활성에 미치는 영향 및 부정소 상피세포의 여러 유형에 관한 연구)

  • 최임순;정경순
    • The Korean Journal of Zoology
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    • v.32 no.3
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    • pp.290-303
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    • 1989
  • The activities of $\beta$-glucosidase, $\beta$-glucuronidase and N-acetyl-$\beta$-glucosaminidase were measured to investigate the relationships of them to sexual maturity. Peritoneal injections of testosterone and dibutyryl cAMP to rats were carried out. As a result, the activities of $\beta$-glucosidase and N-acetyl-$\beta$-glucosaminidase were significantly decreased from the third day and that of P -glucurondiase on the seventh day in the castrated groups. In addition, ihe activities of these three enzymes were significantly increased in the testosterone treated groups for 7 days. In case of dbcAMP injection, the activities of these three enzymes were similar to those of castrated groups or had a tendency to be decreased. On electron microscopic examination, principal cells, basal cells and narrow cells were observed in all regions of epididymis. Principal cells were general forms of columnar epithelial cells. Narrow cells had a number of small vesicles and light cells showed low electron density in comparison to other epithelial cells in cauda epididymis. Halo cells were migrating leucocytes btween epithelial cells.

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Suppression of β-Secretase (BACE1) Activity and β-Amyloid Protein-Induced Neurotoxicity by Solvent Fractions from Petasites japonicus Leaves

  • Hong, Seung-Young;Park, In-Shik;Jun, Mi-Ra
    • Preventive Nutrition and Food Science
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    • v.16 no.1
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    • pp.18-23
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    • 2011
  • Alzheimer's disease (AD) is a neurodegenerative disorder characterized by neuronal loss and extracellular senile plaques containing $\beta$-amyloid peptide (A$\beta$). The deposition of the A$\beta$ peptide following proteolytic processing of amyloid precursor protein (APP) by $\beta$-secretase (BACE1) and $\gamma$-secretase is a critical feature in the progression of AD. Among the plant extracts tested, the ethanol extract of Petasites japonicus leaves showed novel protective effect on B103 neuroblastoma cells against neurotoxicity induced by A$\beta$, as well as a strong suppressive effect on BACE1 activity. Ethanol extracts of P. japonicus leaves were sequentially extracted with methylene chloride, ethyl acetate and butanol and evaluated for potential to inhibit BACE1, as well as to suppress A$\beta$-induced neurotoxicity. Exposure to A$\beta$ significantly reduced cell viability and increased apoptotic cell death. However, pretreatment with ethyl acetate fraction of P. japonicus leaves prior to A$\beta$ (50 ${\mu}M$) significantly increased cell viability (p<0.01). In parallel, cell apoptosis triggered by A$\beta$ was also dramatically inhibited by ethyl acetate fraction of P. japonicus leaves. Moreover, the ethyl acetate fraction suppressed caspase-3 activity to the basal level at 30 ppm. Taken together, these results demonstrated that P. japonicus leaves appear to be a useful source for the inhibition and/or prevention of AD by suppression of BACE1 activity and attenuation of A$\beta$ induced neurocytotoxicity.

A Bacterial Metabolite, Compound K, Induces Programmed Necrosis in MCF-7 Cells via GSK3β

  • Kwak, Chae Won;Son, Young Min;Gu, Min Jeong;Kim, Girak;Lee, In Kyu;Kye, Yoon Chul;Kim, Han Wool;Song, Ki-Duk;Chu, Hyuk;Park, Byung-Chul;Lee, Hak-Kyo;Yang, Deok-Chun;Sprent, Jonathan;Yun, Cheol-Heui
    • Journal of Microbiology and Biotechnology
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    • v.25 no.7
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    • pp.1170-1176
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    • 2015
  • Ginsenosides, the major active component of ginseng, are traditionally used to treat various diseases, including cancer, inflammation, and obesity. Among these, compound K (CK), an intestinal bacterial metabolite of the ginsenosides Rb1, Rb2, and Rc from Bacteroides JY-6, is reported to inhibit cancer cell growth by inducing cell-cycle arrest or cell death, including apoptosis and necrosis. However, the precise effect of CK on breast cancer cells remains unclear. MCF-7 cells were treated with CK ($0-70{\mu}M$) for 24 or 48 h. Cell proliferation and death were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry assays, respectively. Changes in downstream signaling molecules involved in cell death, including glycogen synthase kinase $3\beta$ ($GSK3\beta$), $GSK3\beta$, $\beta$-catenin, and cyclin D1, were analyzed by western blot assay. To block $GSK3\beta$ signaling, MCF-7 cells were pretreated with $GSK3\beta$ inhibitors 1 h prior to CK treatment. Cell death and the expression of $\beta$-catenin and cyclin D1 were then examined. CK dose- and time-dependently inhibited MCF-7 cell proliferation. Interestingly, CK induced programmed necrosis, but not apoptosis, via the $GSK3\beta$ signaling pathway in MCF-7 cells. CK inhibited $GSK3\beta$ phosphorylation, thereby suppressing the expression of $\beta$-catenin and cyclin D1. Our results suggest that CK induces programmed necrosis in MCF-7 breast cancer cells via the $GSK3\beta$ signaling pathway.

The Anti-Cancer Effect of β-Gluconsan Calcium on Oral Cancer Cell (β-Gluconsan Calcium이 구강암 세포의 성장에 미치는 영향)

  • Kim, Ji-Hye;Jung, Yun-Sook;Kim, Hye-Young;Lee, Young-kyun;Kim, Jae-Young;Choi, Youn-Hee;Song, Keun-Bae
    • Journal of dental hygiene science
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    • v.15 no.6
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    • pp.794-799
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    • 2015
  • In recent years, there has been a global trend toward the importance of natural extracts for the prevention and treatment of human diseases. ${\beta}$-glucan is known to have anti-inflammatory activity, anti-cancer, and improvement of immune system. Polycan is purified ${\beta}$-glucan from Aureobasidum pullulans SM-2001. The anti-cancer effects of ${\beta}$-gluconsan calcium, polycan and calcium gluconate complex, were evaluated in human oral cancer YD-10B cells. YD-10B cells were cultured in the presence of 0, 0.5, 0.75, 1 mg/ml ${\beta}$-gluconsan calcium for 48 hours. MTT assay, cell counting, and observation of cell morphology were conducted. The number of cells decreased and cell morphology changed in the 0.5 mg/ml of ${\beta}$-gluconsan calcium. Almost all cells were dead in the 0.75 and 1 mg/ml. MTT assay showed a dose-dependent reduction in cell proliferation (p<0.05). These results indicate that ${\beta}$-gluconsan calcium exhibiting anti-cancer effects in YD-10B cells through changes in cell morphology and cell death.

Nitric Oxide, TNF-${\alpha}$ and TGF-${\beta}$ Formation of Rat Kupffer Cell Activated by the ${\beta}$-Glucan from Ganoderma lucidum (영지의 ${\beta}$-glucan성 다당류에 의해 활성화된 흰쥐 간내 Kupffer 세포의 NO, TNF-${\alpha}$ 및 TGF-${\beta}$ 형성)

  • Han, Man-Deuk;Lee, June-Woo;Jeong, Hoon;Kim, Yong-Seok;Ra, Su-Jung;Yoon, Kyung-Ha
    • Microbiology and Biotechnology Letters
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    • v.27 no.1
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    • pp.28-34
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    • 1999
  • Ganoderan (GAN), an immunomodulating ${\beta}$-glucan from mushroom Ganoderma lucidum, was evaluated for its ability to induce formation of nitric oxide (NO), tumor necrosis factor-${\alpha}$(TNF-${\alpha}$) and transforming growth factor (TGF-${\beta}$) from rat Kupffer cell in vitro. Hepatic macrophages activated by GAN significantly elevated concentration of NO and TNF-${\alpha}$ in cultured medium, but not significantly elevated that of TGF-${\beta}$. GAN-activated Kupffer cells secrete 14.9${\mu}$M (p<0.01) of NO and 2619.5${\rho}$g/ml (p<0.01) of TNF-${\alpha}$after 36hr of incubation at 37$^{\circ}C$. The results revealed that GAN enhanced 4-fold production of NO and 19 fold formation of TNF-${\alpha}$ compared to the control. The proliferation of GAN-activated Kupffer cells was inhibited as compared with its negative control. Comparing the activity among glucans derived from microorganisms, highly branched zymosan, glucomannan from Saccharomyces cerevisiae, significantly increased TNF-${\alpha}$ and NO production. These results indicate that the ${\beta}$-glucan from G. lucidum activates rat Kupffer cell and secretes NO and TNF-${\alpha}$. It also suggest that rat Kupffer cell posses certain receptor for ${\beta}$-anomeric glucan.

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Growth Inhibition of Human Lung Carcinoma Cells by ${\beta}>-lapachone$ through Induction of Apoptosis (Tabebuia avellanedae에서 유래된 ${\beta}>-lapachone$의 인체폐암세포 apoptosis 유발에 관한 연구)

  • Choi, Byung-Tae;Lee, Yong-Tae;Choi, Yung-Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.3
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    • pp.722-728
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    • 2005
  • The DNA topoismerase I inhibitor ${\beta}-lapachone$, the product of a lapacho tree (Tabebuia avellanedae) from South America, activates a novel apoptotic response in a number of cell lines. In the present report, we investigated the effects of ${\beta}-lapachone$ on the growth of human lung in human non-small-cell-lung-cancer A549 cells. Upon treatment with ${\beta}-lapachone$, a concentration-dependent inhibition of cell viability and cell proliferation was observed as measured by hemocytometer counts and MTT assay. The ${\beta}-lapachone-treated$ cells developed many of the hallmark features of apoptosis, including membrane shrinking, condensation of chromatin and DNA fragmentation. These apoptotic effects of ${\beta}-lapachone$ in A549 cells were associated with a marked induction of pro-apoptotic Bax expression, however the levels of anti-apoptotic Bcl-2 expression were decreased in a dose-dependent manner. Accordingly, elevated amount of cyclin-dependent kinase inhibitor p21 expression accompanied by up-regulation of tumor suppressor p53 was observed. By RT-PCR analyses, decrease in gene expression level of telomerase reverse transcriptase and telomeric repeat binding factor were also observed. Thus, these findings suggest that ${\beta}-lapachone$ may be a potential anti-cancer therapeutics for the control of human lung cancer cell model.

Role of ERK (Extracellular Signal Regulated Kinas) and PPARγ (Peroxisome Proliferator-Activated Receptor Gamma) on TGF-β1 Induced Human Endometrial Stromal Cell Decidualization (TGF-β1에 의하여 유도된 인간자궁내막의 탈락막화(Decidualization)에 있어서 ERK (Extracellular Signal Regulated Kinas)와 PPARγ (Peroxisome Proliferator-Activated Receptor Gamma)의 역할)

  • Chang, Hye Jin;Lee, Jae Hoon;Kim, Mi Ran;Hwang, Kyung Joo;Park, Dong Wook;Min, Churl K.
    • Clinical and Experimental Reproductive Medicine
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    • v.33 no.2
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    • pp.105-113
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    • 2006
  • Objective: To investigate the role of ERK and $PPAR{\gamma}$ on the $TGF-{\beta}1$ induced human endometrial stromal cell decidualization in vitro. Method: Endometrial stromal cells are cultured under the following condition: DMEM/F12 (10% FBS, 1 nM E2 and 100 nM P4). $TGF-{\beta}1$ (5 ng/ml), Rosiglitazone (50 nM), and PD98059 ($20{\mu}M$) were added according to experimental purposes. Trypan-Blue and hematocytometer were utilized to count cell number. Enzyme-linked immunosorbent assay (ELISA) and western blotting were utilized to detect proteins. Result: $TGF-{\beta}1$ inhibited proliferation of cultured human endometrial stromal cells and induced expression of PGE2 and prolactin. This effect was mediated by Smad and ERK activation. Administration of rosiglitazone, $PPAR{\gamma}$ agonist, prevented $TGF-{\beta}1$ effect on cell proliferation. Furthermore, Rosiglitazone inhibited $TGF-{\beta}1$ induced activation of ERK, consequently reduced PGE2 and prolactin production. Conclusion: $TGF-{\beta}1$ induced decidualization of endometrial stromal cell through Smad and ERK phosphorylation. $PPAR{\gamma}$ acts as a negative regulator of human ndometrial cell decidualization in vitro.