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Pretreatment of curcumin protects hippocampal neurons against excitotoxin-induced cell death (Curcumin의 전처리는 excitotoxin에 의한 세포사멸로부터 해마신경세포를 보호)

  • Kim, So-Jung;Kim, Keun-Ho;Kong, Kyoung-Hye;Lee, Jae-Won
    • Journal of Life Science
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    • v.17 no.1 s.81
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    • pp.12-17
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    • 2007
  • Curcumin is a natural phenolic yellow curry spice, derived from the tumeric, which has been used for the treatment of diseases associated with oxidative stress and inflammation. Curcumin is known to have both anti-oxidative and anti-inflammatory properties. These properties can be beneficial to protect the brain from the neurodegenerative diseases. We now report the neuroprotective effects of curcumin pretreatment in primary hippocampal neurons to glutamate-induced excitotoxicity. Pretreatment of embryonic mouse hippocampal cell cultures with low does of curcumin protected neurons against glutamate-induced death, however, this neuroprotection was not correlated with the modulation of oxidative stress. Interestingly, high dose of curcumin showed the cytotoxicity in primary cultured hippocampal neurons. Immunoblot analyses showed that levels of stress response. protein HSP70 were significantly elevated in neurons exposed to low dose of curcumin, whereas levels of cleaved PARP were increased in neurons exposed to high dose of curcumin. These findings show that curcumin can modulate neuronal responses to glutamate, and suggest possible use of curcumin and related compounds in the prevention and/or treatment of neurodegenerative disorders.

Protective Effects of Korean Red Ginseng against Alcohol-induced Hepatosteatosis (알코올에 의해 유발된 지방변성증에서 홍삼의 보호효과)

  • Kim, Sun Ju;Ki, Sung Hwan;Lee, Sangkyu
    • Journal of Life Science
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    • v.25 no.3
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    • pp.317-322
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    • 2015
  • Alcohol-induced fatty liver (steatosis) results from excessive generation of reducing equivalents by ethanol metabolism. Generally, chronic ethanol treatment causes hepatosteatosis by regulating sterol regulatory element-binding protein 1c (SREBP-1c), which increases the synthesis of hepatic lipids. The effect of ethanol on SREBP-1c is mediated through mammalian sirtuin-1 (SIRT-1), a NAD+-dependent protein deacetylase that regulates hepatic lipid metabolism. Ginseng is a widely used herbal medicine that is used in Asia for its anti-diabetes and anti-obesity effects. The pharmacological and therapeutic effects of ginseng are primarily produced by bioactive constituents known as ginsenosides. Here, we examined the regulatory effects of Korean red ginseng (KRG) extracts on SREBP-1c and SIRT-1 on lipid homeostasis in AML-12 mouse hepatocytes. AML-12 cells were treated with ethanol and/or KRG extracts (0 - 1,000 μg/ml). Lipid droplets were assayed using Oil red O staining, and western blotting was used to measure SIRT-1 and SREBP-1 expression. Treatment with KRG extracts restored SIRT-1 expression and reduced SREBP-1c expression in ethanol-treated cells. We also showed that KRG extract and ginsenosides Rb2 and Rd significantly decreased SREBP-1 acetylation in ethanol-treated cells. These results show that treatment with KRG extract and its active ginsenoside constituents Rb2 and Rd protected against alcohol-related hepatosteatosis via regulation of SIRT-1 and downstream acetylation of SREBP-1c, which altered hepatic lipid metabolism.

Classification of Antimicrobial Peptides among the Innate Immune Modulators (선천성 면역조절자인 항생펩타이드 분류)

  • Lee, Jong-Hwan
    • Journal of Life Science
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    • v.25 no.7
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    • pp.833-838
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    • 2015
  • Multidrug-resistant super bacterial, fungal, viral, and parasitic infections are major health threaten pathogens. However, to overcome the present healthcare situation, among the leading alternatives to current drugs are antimicrobial peptides (AMPs), which are abundantly produced via various species in nature. AMPs, small host defense proteins, are in charge of the innate immunity for the protection of multicellular organisms such as fish, amphibian, reptile, plants and animals from infection. The number of AMPs identified per year has increased steadily since the 1980s. Over 2,000 natural AMPs from bacteria, protozoa, fungi, plants, and animals have been listed into the antimicrobial peptide database (APD). The majority of these AMPs (>86%) possess 11–50 amino acids with a net charge from 0 to +7 and hydrophobic percentages between 31–70%. This report classified AMP into several categories including biological source, biological functions, peptide properties, covalent bonding pattern, and 3D structure. AMP functions not only antimicrobial activity but facilitates cell biological activity such as chemotatic activity. In addition, fibroblastic reticular cell (FRC) originated from mouse lymph node stroma induced the expression of AMP in inflammatory condition. AMP induced from FRC contained whey acidic protein (WAP) domain. It suggests that the classification of AMP will be done by protein domain.

A Potent Tissue Destructive Activity of Secreted Proteins of Aeromonas hydrophila (조직 괴사 활성을 지닌 Aeromonas hydrophila 의 분비 단백질에 관한 연구)

  • Kim, Kyu Lee;Choe, Yunjeong;Kang, Ho Young
    • Journal of Life Science
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    • v.25 no.2
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    • pp.214-222
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    • 2015
  • Aeromonas hydrophila is the most common water fish pathogen and cause diseases such as hemorrhagic septicemia, dropsy, ulceration and asymptomatic septicemia. A. hydrophila secretes many extracellular products (ECPs) which contribute to effective infection, wide distribution and great adaptability to environmental changes. Crude ECPs of A. hydrophila CK257, a strain used in this study, exhibits a toxic activity to the animals including mouse, rabbit and fish. Toxic symptoms were indicated by tissue damage and skin injuries in animal. When ECPs were subcutaneously injected to animals, skin damages were observed, appearing like necrosis. Preliminary research demonstrated that the active factors are protein component. The crude ECPs were collected after ammonium sulfate precipitation of cell-free culture supernatant. ECPs were fractionated with the use gel filtration chromatography. Five ECP fractions were obtained, of which one fraction was found to be toxic to goldfish. MALDI-TOF analyses provided two interesting proteases called M35 and M28. Both M35 and M28 are known as metalloprotease. Accordingly, proteins in an active fraction exhibited caseinolytic activity. These proteins were difference of caseinolytic activity under different metallic ions. Also active fraction has elastolytic activity. These results suggested that peptidase M28 and M35 may be a candidate factor for tissue necrosis activity about infection with A. hydrophila.

Peptides-derived from Scales of Branchiostegus japonicus Inhibit Ultraviolet B-induced Oxidative Damage and Photo-aging in Skin Cells (피부세포에서 옥돔 비늘로부터 추출한 펩타이드의 UVB에 대한 산화적 손상 및 광 노화 억제)

  • Oh, Min Chang;Kim, Ki Cheon;Ko, Chang-ik;Ahn, Yong Seok;Hyun, Jin Won
    • Journal of Life Science
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    • v.25 no.3
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    • pp.269-275
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    • 2015
  • Collagen peptides, which are found at high concentrations in the human body, are present in animal bones and the skin of marine organisms, namely, fish scales. Collagen is the most abundant structural protein of various connective tissues in animals. Furthermore, it is widely used in biomedical material, pharmaceutical, cosmetic, food, and leather industries. Peptides extracted from scales of various fish protect against ultraviolet B (UVB)-induced skin damage and photo-aging. However, the protective effects of collagen peptides derived from the scales of Branchiostegus japonicus against UVB exposure are unclear. This study investigated the effects of peptides larger than 1 kDa (high-molecular weight peptides [HMP]) and smaller than 1 kDa (low-molecular weight peptides [LMP]), derived from extracts of B. japonicus scales, against UVB-induced skin damage and photo-aging. These peptides scavenged 1,1-diphenyl-2-picrylhydrazyl radicals in a dose-dependent manner. In UVB-exposed HaCaT human keratinocytes, LMP inhibited 8-isoprostane generation, a marker of cellular lipid peroxidation. The peptides also suppressed the UVB-induced increase in tyrosinase activity and melanin content in B16F10 mouse melanoma cells. In addition, the LMP and HMP treatment suppressed UVB-induced elastase and matrix metalloproteinase-1 activities in the HaCaT cells. These results indicate that peptides derived from B. japonicus scales have antioxidant, antiphoto-aging, and skin-whitening effects.

The Anti-inflammatory Effects of Probiotic-produced Exopolysaccharide (프로바이오틱스 생산 exopolysaccharide에 의한 항염증 활성)

  • Lee, Seung Hoon;Kwon, Min-Jeong;Kang, Hyung-Taek;Chung, Chung Wook;Kim, Byung Oh;Kim, Jong-Sik
    • Journal of Life Science
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    • v.25 no.6
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    • pp.709-714
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    • 2015
  • The present study isolated seven different kinds of probiotics from various food sources and identified them with Bacillus sp. and Lactobacillus sp. by 16S rDNA sequencing. Their supernatants were prepared after a 24 hr culture, and their effects on nitric oxide (NO) production in mouse RAW 264.7 cells were investigated. Among the treated samples, the culture supernatants of two strains (Bacillus sp. FG-1 and Lactobacillus sp. FG-6) significantly decreased NO production in LPS-activated RAW 264.7 cells. Moreover, they dramatically reduced the expression of pro-inflammatory genes such as COX-2, iNOS, and TNF-α. To examine whether exopolysaccharide (EPS) is responsible for the anti-inflammatory effects of probiotics, EPS was purified from the culture supernatants of Bacillus sp. FG-1 and Lactobacillus sp. FG-6 strains. The EPS treatment produced by FG-1 and FG-6 strains decreased NO production in a dose-dependent manner in LPS-stimulated RAW 264.7 cells without affecting cell viability, while also reducing pro-inflammatory gene expression. Overall, these results suggest that EPS might be one of the key molecules responsible for the anti-inflammatory effects of probiotics.

Effects of Histone Deacetylase Inhibitor, Trichostatin A, on the Differentiation of C2C12 Myoblasts and the Expression of Cell Cycle Regulators (히스톤 탈아세틸화 효소 억제제 trichostatin A가 C2C12 myoblast 세포 분화와 세포주기 조절인자의 발현에 미치는 영향)

  • Lee, Won-Jun
    • Journal of Life Science
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    • v.17 no.7 s.87
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    • pp.976-982
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    • 2007
  • The purpose of this study was to determine the modulating effects of histone deacetylase inhibitor, trichostatin A, on the differentiation of mouse C2C12 myoblasts. We demonstrated that trichostatin A induced morphological changes of C2C12 myoblasts into smooth muscles and significantly increased the gene expression of smooth muscle markers including smooth muscle ${\alpha}-actin$ and transgelin. These results were due to the change in the expression level of cell cycle regulators in trichostatin A-treated C2C12 cells. Real-time PCR data revealed that cyclin dependent kinase inhibitor, p21, mRNA expression was significantly increased in trichostatin A-treated C2C12 cells. However, trichostaDn A rapidly decreased cyclin Dl mRNA expression necessary for cell cycle progression in 24hr after treatment. In conclusion, the strong inhibitory effects of trichostatin A on histone deacetylation induced transdifferentiation of C2C12 myoblasts into smooth muscle cells and these results are partly due to the changes in the expression of cell cycle regulators such as p21 and cyclin D1.

Comparison of Arylphorin of Antheraea pernyi with Those of Several Lepidopteran Wild Silkmoths by Western Blot Analysis. (작잠(Antheraea pernyi) arylphorin의 항체를 이용한 수종의 나비목 야생 견사곤충들 간의 면역학적 비교)

  • Park, Nam-Sook;Kim, Mi-Ae;Park, Hyun-Chul;Kim, Keun-Ki;Jin, Byung-Rae;Lee, Sang-Mong
    • Journal of Life Science
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    • v.18 no.3
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    • pp.409-413
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    • 2008
  • The occurences of proteins relating to Antheraea pernyi arylphorin in haemolymph, fat body, integument, midgut and silkgland of the wild silkmoths, Antheraea yamamai, Antheraea pernyi, Samia cynthia pryeri and Actias gnoma in the 5th larval instar were investigated by immunoblot analysis using mouse polyclonal antibody against A. pernyi arylphorin as probe. In A. yamamai, A. pernyi, S. cynthia pryeri and A. gnoma, the major immunoreactive antigenic proteins with a molecular weight of 80 KDa against the antisera of the A. pernyi arylphorin were clearly observed in the haemolymph, but in the integument, fat body, midgut and silkgland of the corresponding wild silkmoths the presence of the immunoreactive proteins were very variable. These results suggest that the A. pernyi arylphorin has almost same immunological identity with those of the wild silkmoths, A. yamamai, S. cynthia pryeri and A. gnoma though the distribution of the corresponding antigenic arylphorins is different according to the tissues of the wild silkmoths.

Correlation of Gene Expression between Adiponectin and Glucose Transporter 4 in Mouse Adipose Tissue (생쥐 지방조직에서의 아디포넥틴과 포도당수송체-4 유전자 발현의 상관관계)

  • Lee, Yong-Ho
    • Journal of Life Science
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    • v.24 no.8
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    • pp.895-902
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    • 2014
  • Adiponectin has been known to improve insulin sensitivity and elicit glucose uptake via increased glucose transporter 4 (GLUT4) translocation. In the current study, mRNA expression levels of adiponectin and GLUT4 were measured in subcutaneous adipose tissue from C57BL/6 mice fed normal (ND) or high-fat diet (HFD) until 16, 26, 36, 47, or 77 weeks of age starting from 6 weeks of age. Expression levels were also measured in mice with calorie restriction (CR) and in thiazolidinedione (TZD) treated mice. Using quantitative real-time PCR, we demonstrated that GLUT4 expression in adipose tissue significantly decreased in HFD mice groups and increased in CR (p<0.05) and TZD (p=0.007) groups while there was no difference in adiponectin mRNA expression levels between experimental and control groups. General linear regression models were used to assess the association of gene expression levels between adiponectin and GLUT4 and to determine whether adiponectin affects GLUT4 transcription. mRNA expression levels of adiponectin and GLUT4 are significantly associated each other in mice fed a ND (p<0.0001) or HFD (p<0.0001), in groups separated into each age and diet, and CR group (p=0.002), but not in TZD group (p=0.73). These results demonstrated that gene expression of adiponectin and GLUT4 is strongly associated, suggesting that there is a common regulatory mechanism for adiponectin and GLUT4 gene expression and/or adiponectin has a direct role in GLUT4 gene expression in adipose tissue.

Functional Analysis of Fibroblastic Reticular Cells Derived from Mouse Lymph Node via Bidirectional Crosstalk with T Cells (T세포와 양방향 작용을 통한 마우스 림프절로부터 분리된 fibroblastic reticular cell의 기능적 분석)

  • Park, Sung Hee;Lee, Jong-Hwan
    • Journal of Life Science
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    • v.23 no.10
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    • pp.1199-1208
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    • 2013
  • Fibroblastic reticular cells (FRCs) form the structural backbone of the T zone provide a guidance path for immigrating T cells in the lymph node (LN). FRCs may contribute directly to developing T-cell biology in the LN and allow analyses of fundamental aspects of FRC biology related to T cells. FRCs inhibited T-cell apoptosis, and FRC culture supernatants strongly induced the expression of Bcl-xL in T cells against doxorubicin. Coculture of FRC and T cells resulted in rearrangements of the actin cytoskeleton, as well as global changes in the morphology of the FRCs. In addition, when cocultured, the T cells adhered to the FRC monolayer, and the membrane intercellular adhesion molecule (ICAM)-1 was slightly increased by day-dependent manner. In contrast, the expression of soluble ICAM-1 was dramatically increased in a day-dependent manner. Several chemokines, such as CCL5, CXCL1, CXCL5, CXCL16, CCL8, CXCL13, and ICAM-1, and MMPs were expressed in FRCs sensed by tumor necrosis factor (TNF) families. Nuclear factor kappa B ($NF{\kappa}B$)-RelA of the $NF{\kappa}B$ canonical pathway was translocated into FRC nuclear by $TNF{\alpha}$. In contrast, p52 proteolyzed from p100, a counterpart of RelB of the noncanonical $NF{\kappa}B$ pathway, accumulated in the peripheral FRC nucleus by agonistic anti-$LT{\beta}R$ antibody. In summary, we propose a model in which FRCs engage in bidirectional crosstalk to increase the efficiency of T-cell biology. This cooperative feedback loop may help to maintain tissue integrity and function during immune responses.