• Title/Summary/Keyword: membrane function

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Ameliorative effect of onion (Allium Cepa L.) flesh and peel on amyloid-β-induced cognitive dysfunction via mitochondrial activation (미토콘드리아 활성화를 통한 양파(Allium Cepa L.) 과육 및 과피의 Amyloid-β 유도성 인지손상에 대한 개선효과)

  • Park, Seon Kyeong;Lee, Uk;Kang, Jin Yong;Kim, Jong Min;Shin, Eun Jin;Heo, Ho Jin
    • Korean Journal of Food Science and Technology
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    • v.52 no.3
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    • pp.263-273
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    • 2020
  • In this study, in order to confirm the ameliorative effects of onion (Allium cepa L.) flesh and peel on amyloidbeta (Aβ)-induced cognitive dysfunction, we evaluated their in vitro neuroprotection and in vivo cognitive functions. As the result of in vitro neuroprotection, the protective effect of the ethyl acetate fraction of onion flesh (EOF) on Aβ-induced cytotoxicity was similar to that of the ethyl acetate fraction of onion peel (EOP). In the behavioral tests, the EOF and EOP effectively improved the Aβ-induced learning and memory impairments. For this reason, it could be concluded that the EOF and EOP improved the antioxidant activities (superoxide dismutase, oxidized glutathione/total glutathione, and malondialdehyde) in brain tissue. In addition, the EOF and EOP effectively activated mitochondrial functions by protecting the mitochondrial membrane potential, ATP, mitochondria-mediated protein (BAX and cytochrome c), and caspase 3/7 activities. The EOF and EOP also improved the cholinergic system (acetylcholinesterase and acetylcholine). Therefore, we suggest that onion could be used for management of Aβ-induced cognitive dysfunction.

Biochemical Properties and Physiological Functions of Plant β-D-fructofuranosidase (식물 β-D-fructofuranosidase의 화학적 성질과 생리적 기능)

  • Kim, Donggiun
    • Journal of Life Science
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    • v.27 no.7
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    • pp.849-856
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    • 2017
  • The ${\beta}$-D-fructofuranosidase (EC 3.2.1.26) is an important enzyme from a historical point of view, discovered by French biologist Berthelot in 1860 and was first used to study enzymology. ${\beta}$-D-fructosfuranosidase catalyzes the hydrolysis of sucrose into D-glucose and D-fructose. Four biochemical subgroups of ${\beta}$-D-fructofuranosidase have been investigated in plants. There are vacuolar (soluble acid), cytoplasmic (soluble alkaline), membrane-bound (insoluble alkaline), and cell wall-bound (insoluble acid) ${\beta}$-D-fructofuranosidase by purification. Their biochemical characteristics are distinct. It suggested that those enzymes might be different gene products. The contribution of each of these enzymes to sucrose management in the plant is likely to be correlated with their localization. Common localization in developing cells in tissues from a range of developmental stages and plant parts suggests that all of the isoforms may be closely involved in nutrient transport. The ${\beta}$-D-fructofuranosidases were most commonly found associated with maturing tissues in developing fruits, leaves, and roots. The ${\beta}$-D-fructofuranosidase activity varies in the relationship between growth and expansion through cell division, development of storage organs and tissues, and the relationship of plant defense responses. It is necessary to summarize more researches in order to know the definite physiological function.

Applying the New Technology for Making Pontic Ridge Lap in Posterior Bridge Restoration (대체 신기법을 적용한 구치부 교의치 pontic ridge lap 제작방법)

  • Kim, Wook-Tae
    • Journal of Dental Rehabilitation and Applied Science
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    • v.29 no.3
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    • pp.308-316
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    • 2013
  • The purpose of this study is to investigate the production method of posterior bridges pontic ridge lap type which prevents the infection in bridge pontic base and is able to cleanse itself, in the process of producing final prothesis that maintains healthy mucous membrane of oral cavity and interproximal papilla, minimizing diastema, is aesthetic and has no effect on pronunciation. New technology is applied to make optimal pontic base which prevent inflammation and clean itself and its products were clinically evaluated in 10 places of dental clinics in busan and gyeongnam. The making of posterior 3 unit bridge pontic base, it was presented as the new technology of forming ridge lab type and to carry out clinical validation, existing conventional method and the new technology were compared. Pontic base made with the existing conventional method cause infection and other periodontal disease by 96% but the pontic base made with the new technology cause infection and other periodontal disease by 3%. Remains of food cause infection and other periodontal disease 100% by the existing conventional method and 91% by the new technology, showing a distinct difference. However, after a gargle, the new technology had low 13%. Additionally, the pontic base made with the existing conventional method showed 71% of chance, the new technology method showed 8% of chance in terms of self-cleansing.

Ultrastructure of Oocytes During Oogenesis and Oocyte Degeneration Associated with Follicle Cells in Female Sinonovacula constricta(BIVALVIA: PHARIDAE) in Western Korea

  • Chung, Ee-Yung;Ko, Cheol-Hwan;Kang, Hee-Woong;Choi, Ki-Ho;Jun, Je-Cheon
    • Animal cells and systems
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    • v.12 no.4
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    • pp.313-319
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    • 2008
  • The ultrastructure of oocytes during oogenesis and oocyte degeneration associated with follicle cells in female Sinonovacula constricta(Lamarck, 1818) were investigated by electron microscope observations. Ovarian follicles are surrounded by a matrix of vesicular connective tissue cells(VCT cells). VCT cells contain large quantities of glycogen particles and several lipid droplets in their cytoplasm. It is suggested that VCT cells act as a source of nutrients for vitellogenesis during oogenesis. In early vitellogenic oocytes, several coated vesicles, which appear at the basal region of the oocyte, lead to the formation of membrane-bound vesicles via endocytosis. The uptake of nutritive materials in coated vesicles formed by endocytosis appears through the formation of coated pits on the oolemma during vitellogenesis. During the late stage of oogenesis, yolk precursors(yolk granules), mitochondria and lipid droplets are present in the cytoplasm of late vitellogenic oocytes. In particular, proteinaceous yolk granules containing several different components are intermingles and form immature yolk granules. In the mature oocyte, small immature yolk granules are intermingled and form large mature yolk granules. Vitellogenesis occurs through a process of autosynthesis, involving combined activity of the Golgi complex, mitochondria and rough endoplasmic reticulum in the cytoplasm of vitellogenic oocytes. The process of heterosynthesis is where extraovarian precursors are incorporated into oocytes by endocytosis at the basal region of early vitellogenic oocytes before the formation of the vitelline coat. Follicle cells appear to play an important role in vitellogenesis and oocyte degeneration. The functions of attached follicle cells to the oocyte during oocyte degeneration are phagocytosis and digestion of phagosomes originating from oocyte degeneration. After digestion of phagosomes, it is assumed that the function of follicle cells can permit a transfer of yolk precursors necessary for vitellogenesis and allows for the accumulation of glycogen and lipid during oocyte degeneration, which can be employed by vitellogenic oocytes. Follicle cells of S. constricta may possess a lysosomal system for induction of oocyte breakdown and might resorb phagosomes in the cytoplasm for nutrient accumulation during oocyte degeneration.

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.

The Effects of Sera from Amyotrophic Lateral Sclerosis Patients on Neuromuscular Transmission and Calcium Channels in Mice

  • Yan, Hai-Dun;Kim, Ji-Mok;Jung, Sung-Jun;Kim, Jun
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.1
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    • pp.101-117
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    • 1999
  • Amyotrophic lateral sclerosis (ALS) is a degenerative neuromuscular disease of unknown etiology in which the upper and lower motor neurons are progressively destroyed. Recent evidences support the role of autoimmune mechanisms in the pathogenesis of ALS. This study investigated the effects of sera from ALS patients on neuromuscular transmission in phrenic nerve-hemidiaphragm preparations and on calcium currents of single isolated dorsal root ganglion (DRG) cells in mice. Mice were injected with either control sera from healthy adults or ALS sera from 18 patients with ALS of sporadic form, for three days. Miniature end plate potential (MEPP) and nerve-evoked end plate potential (EPP) were measured using intracellular recording technique and the quantal content was determined. Single isolated DRG cells were voltage-clamped with the whole-cell configuration and membrane currents were recorded. Sera from 14 of 18 ALS patients caused a significant increase in MEPP frequency in normal Ringer's solution $(4.62{\pm}0.14\;Hz)$ compared with the control $(2.18{\pm}0.15\;Hz).$ In a high $Mg^{2+}/low\;Ca^{2+}$ solution, sera from 13 of 18 ALS patients caused a significant increase in MEPP frequency, from $2.18{\pm}0.31$ Hz to $6.09{\pm}0.38$ Hz. Sera from 11 of 18 patients produced a significant increase of nerve-evoked EPP amplitude, from $0.92{\pm}0.05$ mV to $1.30{\pm}0.04$ mV, while the other seven ALS sera did not alter EPP amplitude. In the ALS group, EPP quantal content was also elevated by the sera of 14 patients (from $1.49{\pm}0.07$ to $2.35{\pm}0.07).$ MEPP frequency and amplitude in wobbler mouse were $4.03{\pm}0.53$ Hz and $1.37{\pm}0.18$ mV, respectively, which were significantly higher than those of wobbler controls (wobblers without the symptoms of wobbler). Sera from ALS patients significantly reduced HVA calcium currents of DRG cells to 42.7% at -10 mV. Furthermore, the inactivation curve shifted to more negative potentials with its half-inactivation potential changed by 6.98 mV. There were, however, significant changes neither in the reversal potential of $I_{Ca}$ nor in the I-V curve. From these results it was concluded that: 1) The serum factors of sporadic ALS patients increase neuromuscular transmission and can alter motor nerve terminal presynaptic function. This suggests that ALS serum factors may play an important role in the early stage of ALS, and 2) Calcium currents in DRG cells were reduced and rapidly inactivated by ALS sera, suggesting that in these cells, ALS serum factors may exert interaction with the calcium channel.

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Nafamostat Mesilate Inhibits TNF-${\alpha}$-Induced Vascular Endothelial Cell Dysfunction by Inhibiting Reactive Oxygen Species Production

  • Kang, Min-Woong;Song, Hee-Jung;Kang, Shin Kwang;Kim, Yonghwan;Jung, Saet-Byel;Jee, Sungju;Moon, Jae Young;Suh, Kwang-Sun;Lee, Sang Do;Jeon, Byeong Hwa;Kim, Cuk-Seong
    • The Korean Journal of Physiology and Pharmacology
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    • v.19 no.3
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    • pp.229-234
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    • 2015
  • Nafamostat mesilate (NM) is a serine protease inhibitor with anticoagulant and anti-inflammatory effects. NM has been used in Asia for anticoagulation during extracorporeal circulation in patients undergoing continuous renal replacement therapy and extra corporeal membrane oxygenation. Oxidative stress is an independent risk factor for atherosclerotic vascular disease and is associated with vascular endothelial function. We investigated whether NM could inhibit endothelial dysfunction induced by tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$ ). Human umbilical vein endothelial cells (HUVECs) were treated with TNF-${\alpha}$ for 24 h. The effects of NM on monocyte adhesion, vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 (ICAM-1) protein expression, p38 mitogenactivated protein kinase (MAPK) activation, and intracellular superoxide production were then examined. NM ($0.01{\sim}100{\mu}g/mL$) did not affect HUVEC viability; however, it inhibited the increases in reactive oxygen species (ROS) production and p66shc expression elicited by TNF-${\alpha}$ (3 ng/mL), and it dose dependently prevented the TNF-${\alpha}$ -induced upregulation of endothelial VCAM-1 and ICAM-1. In addition, it mitigated TNF-${\alpha}$ -induced p38 MAPK phosphorylation and the adhesion of U937 monocytes. These data suggest that NM mitigates TNF-${\alpha}$ -induced monocyte adhesion and the expression of endothelial cell adhesion molecules, and that the anti-adhesive effect of NM is mediated through the inhibition of p66shc, ROS production, and p38 MAPK activation.

Finestructure and Function of Vas deferens in a freshwater Prawn Macrobrachium nipponense (징거미새우, Macrobrachium nipponense 수정관의 미세구조와 기능)

  • Kim Dae Hyun;Lee Jae Young;Jung Jee Hyun;Kang Jung Ha;Lee Bok Kyu;Han Chang Hee
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.4
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    • pp.424-430
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    • 2002
  • Vas deferens is a long tube and could be divided into four regions as its morphological characters: a short and slender proximal region, a convoluted region, a straight and more thick distal region, and an ejaculatory duct, It is connected with the posterior outer horns of the testis and runs to the gonopores opened on the coxa of the fifth walking legs, The proximal region consists almost entirely of simple cuboidal epithelial cells, $12\~28{\mu}$m in height, surrounded by a thin basal membrane. A small aggregation of high cuboidal epithelium is obsened from one side of the proximal region. The convoluted and distal region is composed of two kinds of epithelial cells; high cuboidal epithelial cells, $40\~120{\mu}m$ in height located in dorsal portion and simple cuboidal epithelial cells of $12\~28{\mu}$m in height located in ventral and lateral portion. The ejaculatory duct is surrounded with two kinds of muscle layers, inner longitudinal and outer circular muscle fibers, The lumen is lined with high and simple cuboidal epithelium in almost equal proportions. The proximal region contains mature sperm and basophilic substances. The eosinophilic substances appeared newly going toward the convoluted region and are laid along simple cuboidal epithelial cell layer. Tube-like content (spermatophore) of the vas deferens is ejaculated from a pair of genital pores at mating. Two masses of the content fuse together side by side and are usually deposited on the female thorax between the second and fourth or fifth pereiopods, The spermatophore formed measures $2.7\~4.0$ mm in length and $1.5\~2.7$ mm in width.

The Effect of Salviae Radix on Oxidat-Inhibition of Phosphate Uptake in Renal Proximal Tubular Cells (단삼약침액(丹蔘藥鍼液)이 신장(腎臟) 근위세뇨관세포(近位細尿管細胞)에서 산화제(酸化劑)에 의한 인산(燐酸)의 이동억제(移動抑制)에 미치는 영향(影響))

  • Lee, Ho-Dong;Youn, Hyoun-Min;Jang, Kyung-Jeon;Song, Choon-Ho;Ahn, Chang-Beohm
    • Journal of Acupuncture Research
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    • v.17 no.3
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    • pp.208-218
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    • 2000
  • This study was undertaken to determine if Salviae Radix (SR) exerts protective effect against oxidant-induced inhibition of phosphate uptake in renal proximal tubular cells. Membrane transport function and cell death were evaluated by measuring phosphate uptake and trypan blue exclusion, respectively, in opossum kidney (OK) cells, an established proximal tubular cell line. $H_2O_2$ was used as a model oxidant. $H_2O_2$ inhibited the phosphate uptake in a dose-dependent manner over the concentration range of 0.1-0.5 mM. Similar fashion was observed in cell death. However, the phosphate uptake was more vulnerable to $H_2O_2$ than cell death, suggesting that $H_2O_2$-induced inhibition of phosphate uptake is not totally attributed to cell death. Decreasedphosphate uptake was associated with ATP depletion and inhibition of $Na^+$-pump activity as determined by direct inhibition of $N^+-K^+$-ATPase activity. When cells were treated with $H_2O_2$ in the presence of 0.05% SR, the inhibition of phosphate uptake and cell death induced by $H_2O_2$ was significantly attenuated. SR restored ATP depletion and decreased $Na^+-K^+$-ATPase activity, and this is likely responsible for the protective effect of SR on decreased phosphate uptake. The protective effect of SR was similar to the $H_2O_2$ scavenger catalase. SR reacts directly with $H_2O_2$ to reduce the effective concentration of the oxidant. The iron chelator deferoxamine prevented the inhibition of phosphate uptake and cell death induced by $H_2O_2$, suggesting that $H_2O_2$-induced cell injury is resulted from an iron-dependent mechanism. These results indicate that SR exerts the protective effect against $H_2O_2$-induced inhibition of phosphate uptake by reacting directly with $H_2O_2$ like the $H_2O_2$scavenger enzyme catalase, in OK cells. However, the underlying mechanism remains to be explored.

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Preparation of Ion Exchange Membranes for Fuel Cell Based on Crosslinked Poly(vinyl alcohol) with Poly(acrylic acid-co-maleic acid)

  • Kim, Dae-Sik;Park, Ho-Bum;Lee, Chang-Hyun;Lee, Young-Moo;Moon, Go-Young;Nam, Sang-Yong;Hwang, Ho-Sang;Yun, Tae-II;Rhim, Ji-Won
    • Macromolecular Research
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    • v.13 no.4
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    • pp.314-320
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    • 2005
  • Crosslinked poly(vinyl alcohol) (PVA) membranes were prepared at various crosslinking temperatures using poly(acrylic acid-co-maleic acid) (PAM) containing different PAM contents. The thermal properties of these PVA/PAM membranes prepared at various reaction temperatures were characterized using differential scanning calorimetry (DSC). The proton conductivity and methanol permeability of PVA/PAM membranes were then investigated as PAM content was varied from 3 to 13 wt%. It was found that the proton and methanol transport were dependent on PAM content in their function both as crosslinking agent and as donor of hydrophilic -COOH groups. Both these properties decreased monotonously with increasing PAM concentration. The proton conductivities of these PVA/PAM membranes were in the range from $10^{-3}\;to\;10^{-2}S/cm$ and the methanol permeabilities from $10^{-7}\;to\;10^{-6}cm^{2}/sec$. In addition, the effect of operating temperature up to $80^{\circ}C$ on ion conductivity was examined for three selected membranes: 7, 9 and 11 wt% PAM membranes. Ion conductivity increased with increasing operating temperature and showed and S/cm at $80^{\circ}C$, respectively. The effects of crosslinking and ionomer group concentration were also examined in terms of water content, ion exchange capacity (IEC), and fixed ion concentration. In addition, the number of water molecules per ionomer site was calculated using both water contents and IEC values. With overall consideration for all the properties measured in this study, $7{\sim}9\;wt%$ PAM membrane prepared at $140^{\circ}C$ exhibited the best performance. These characteristics of PVA/PAM membranes are desirable in applications related to the direct methanol fuel cell (DMFC).