• Title/Summary/Keyword: Intracellular pH

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Intracellular Concentrations of NAD(P), NAD(P)H, and ATP in a Simulated Oxic-settling-anaerobic (OSA) Process (OSA 공정의 세포 내 ATP, NAD(H), NADP(H) 농도)

  • Ventura, Jey-R Sabado;Nam, Ji-Hyun;Yang, Benqin;Na, Ri;Kil, Hyejin;Nam, Deok-Hyeon;Kang, Ki-Hoon;Jahng, Deokjin
    • Journal of Korean Society on Water Environment
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    • v.31 no.6
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    • pp.599-609
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    • 2015
  • In order to investigate why OSA (oxic-settling-anaerobic) process produces less sludge than CAS (conventional activated sludge) process, sequential cultivation through 1st aerobic-anaerobic-2nd aerobic conditions, were carried out. Then, the intracellular concentrations of adenosine triphosphate (ATP), nicotinamide adenine dinucleotide (NAD and NADH), and nicotinamide adenine dinucleotide phosphate (NADP and NADPH) were monitored for these three stages. Results showed that the concentrations of these energy substances rapidly decreased through time in both aerobic and anaerobic conditions but the anaerobic culture contained the lower energy level than aerobic culture. The 2nd aerobic culture that experienced anaerobic condition showed lower concentration of these energy substances than those of the 1st aerobic culture. Meanwhile, the anaerobic culture corresponding to the sludge holding stage of OSA was subjected to different soluble chemical oxygen demand (SCOD) levels, detention time, and temperature to evaluate the effects of these variations on the energy level difference between the 1st and 2nd aerobic stages. The lower the SCOD concentration, the longer detention time; and the higher temperature in the anaerobic stage tended to further reduce the intracellular level of the 2nd aerobic culture. On the average, the intracellular energy level of the anaerobic and 2nd aerobic stage were 57.73% and 39.12% of the 1st aerobic culture, respectively. These indicated that the insertion of an anaerobic stage between two aerobic stages could lower the intracellular energy levels, hence the lower the sludge in OSA than CAS process. Moreover, manipulation of the operating conditions of the intervening anaerobic stage can change intracellular energy levels thereby controlling sludge production.

Differential Expression of Three Novel Carbonic Anhydrases (CAs) Genes in Marine Dinoflagellate Prorocentrum minimum Against Various pH Conditions (해양 와편모조류 Prorocentrum minimum 기원 신규 탄산무수화효소(CAs) 유전자 3종의 차등 pH 대응 발현)

  • Shin, Jeongmin;Lee, Ha-Eun;Kim, Han-Sol;Ki, Jang-Seu
    • Ocean and Polar Research
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    • v.44 no.3
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    • pp.209-220
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    • 2022
  • Carbonic anhydrase (CA) is a key controller of the carbon concentrating mechanism (CCM), and is known to be affected by ambient pH and CO2 compositions. Herein, we characterized three novel CAs genes (PmCA1, 2, and 3) from the marine dinoflagellate Prorocentrum minimum, and evaluated the relative expressions of the PmCAs and photosynthetic genes PmatpB and PmrbcL under different pH conditions. Each PmCA was predicted to have amino acid residues constituting the zinc binding site. With signal peptide, PmCA1 and PmCA2 were predicted to be intracellular CAs located in the cytoplasm and chloroplast membrane, respectively. On the other hand, PmCA3 was predicted to be extracellular CA located in the plasma membrane. Also, PmCA1 was classified into the beta family, and PmCA2 and PmCA3 were classified into the alpha family via phylogenic analysis. The photosynthesis efficiency of P. minimum was similar at pH 7 to 9, and decreased significantly at pH 6 and pH 10. Overall, relative gene expression levels of the three PmCAs decreased at low pH, and increased as pH increased. Photosynthesis related genes, PmatpB and PmrbcL, showed similar expression patterns to those of PmCAs. These results suggest that changes in seawater pH may affect photosynthesis and CO2 metabolism in marine dinoflagellates.

Effect of β-Mercaptoethanol Supplement during In Vitro Maturation on IVM, IVF and Glutathione Level in Porcine Oocytes (돼지 미성숙 난포란의 체외성숙 시 β-mercaptoethanol의 첨가가 체외성숙, 체외수정 및 Glutathione 수준에 미치는 영향)

  • Oh, Shin-Ae;Kim, Chang-Keun;Chung, Yung-Chai;Chang, Yoo-Min;Pang, Myung-Geol
    • Journal of Animal Science and Technology
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    • v.47 no.3
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    • pp.363-370
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    • 2005
  • Experiments were conducted to determine the effects of beta-mercaptoethanol ($\beta$-ME) supplements to the in vitro maturation (IVM) medium on in vitro fertilization (IVF) and intracellular glutathione (GSH) concentration. Porcine cumulus-intact oocytes were matured in TCM-I99 medium containing porcine follicular fluid, sodium pyruvate, D-glucose, FBS, hormonal supplements, and $\beta$-ME (0, 25, 50 and 100 ${\mu}$M) for 36 to 46h. After culture, cumulus-free matured oocytes were co-incubated with epididymal spermatozoa for 18h. There were no significant differences in the maturation rate among treatment groups. However, increases (P < 0.05) in intracellular GSH concentration before and after. fertilization were observed in 50 ${\mu}$M $\beta$-ME supplements to the IVM medium. Also, increases (P < 0.05) in male pronuclear formation after IVF were observed in same treatment group. In conclusion, supplementing $\beta$-ME into the IVM medium increased intracellular GSH concentrations and increased fertilization in vitro.

The Effect of Caffeic Acid Phenethyl Ester (CAPE) on Phagocytic activity of septic Neutrophil in vitro

  • Eun-A Jang;Hui-Jing Han;Tran Duc Tin;Eunye Cho;Seongheon Lee;Sang Hyun Kwak
    • Biomedical Science Letters
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    • v.29 no.4
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    • pp.211-219
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    • 2023
  • Caffeic acid phenethyl ester (CAPE) is an active component of propolis obtained from honeybee hives. CAPE possesses anti-mitogenic, anti-carcinogenic, anti-inflammatory, and immunomodulatory activities in diverse systems, which know as displays antioxidant activity and inhibits lipoxygenase activities, protein tyrosine kinase, and nuclear factor kappa B (NF-κB) activation. This study aimed to investigate the effect of CAPE on lipopolysaccharide (LPS)-induced human neutrophil phagocytosis. Human neutrophils were cultured with various concentrations of CAPE (1, 10, and 100 µM) with or without LPS. The pro-inflammatory proteins (tumor necrosis factor-alpha [TNF-α], interleukin [IL]-6 and IL-8) levels were measured after 4 h incubation. To investigate the intracellular signaling pathway, we measured the levels of mitogen-activated protein kinases (MAPK), including phosphorylation of p38, extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) and c-Jun N-terminal kinase (JNK). Next, to evaluate the potential phagocytosis, neutrophils were labeled with iron particles of superparamagnetic iron oxide nanoparticles (SPIONs, 40 nm) for 1 h in culture medium containing 5 mg/mL of iron. The labeling efficiency was determined by Prussian blue staining for intracellular iron and 3T-wighted magnetic resonance imaging. CAPE decreased the activation of intracellular signaling pathways, including ERK1/2 and c-Jun, and expression of pro-inflammatory cytokines, including TNF-α and IL-6, but had no effect on the signaling pathways of p38 and cytokine IL-8. Furthermore, images obtained after mannan-coated SPION treatment suggested that CAPE induced significantly higher signal intensities than the control or LPS group. Together, these results suggest that CAPE regulates LPS-mediated activation of human neutrophils to reduce phagocytosis.

Alpha-linolenic acid enhances maturation and developmental competence via regulation of glutathione, cAMP and fatty acid accumulation during in vitro maturation of porcine oocytes

  • Jeon, Ye-Eun;Hwangbo, Yong;Kim, Sun-Young;Park, Choon-Keun
    • Journal of Animal Reproduction and Biotechnology
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    • v.35 no.4
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    • pp.357-365
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    • 2020
  • The aim of present study was to investigate regulatory mechanism of alpha-linolenic acid (ALA) during in vitro maturation (IVM) on nuclear and cytoplasmic maturation of porcine oocytes. Basically, immature cumulus-oocyte complexes (COCs) were incubated for 22 h in IVM-I to which hormone was added, and then further incubated for 22 h in IVM-II without hormone. As a result, relative cumulus expansion was increased at 22 h after IVM and it was enhanced by treatment of ALA compared with control group (p < 0.05). During IVM process within 22 h, cAMP level in oocytes was decreased at 6 h (p < 0.05) and it was recovered at 12 h in ALA-treated group, while oocytes in control group recovered cAMP level at 22 h. In cumulus cells, it was reduced in all time point (p < 0.05) and ALA did not affect. Treatment of ALA enhanced metaphase-I (MI) and MII population of oocytes compared with oocytes in control group at 22 and 44 h, respectively (p < 0.05). Intracellular GSH levels in ALA group was increased at 22 and 44 h after IVM (p < 0.05), whereas it was increased in control group at 44 h after IVM (p < 0.05). In particular, the GSH in ALA-treated oocytes during 22 h of IVM was higher than control group at 22 h (p < 0.05). Lipid amount in oocytes from ALA group was higher than control group (p < 0.05). Treatment of ALA did not influence to absorption of glucose from medium. Cleavage and blastocyst formation of ALA-treated oocytes were enhanced compared with control group (p < 0.05). These findings suggest that supplementation of ALA could improve oocyte maturation and development competence through increasing GSH synthesis, lipid storage, and regulation of cAMP accumulation during early 22 h of IVM, and these might be mediated by cumulus expansion.

Dual Effect of $H_2O_2$ on the Regulation of Cholecystokinin-induced Amylase Release in Rat Pancreatic Acinar Cells

  • An, Jeong-Mi;Rhie, Jin-Hak;Seo, Jeong-Taeg
    • International Journal of Oral Biology
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    • v.31 no.4
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    • pp.127-133
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    • 2006
  • [ $H_2O_2$ ], a member of reactive oxygen species (ROS), is known to be involved in the mediation of physiological functions in a variety of cell types. However, little has been known about the physiological role of $H_2O_2$ in exocrine cells. Therefore, in the present study, the effect of $H_2O_2$ on cholecystokinin (CCK)-evoked $Ca^{2+}$ mobilization and amylase release was investigated in rat pancreatic acinar cells. Stimulation of the acinar cells with sulfated octapeptide form of CCK (CCK-8S) induced biphasic increase in amylase release. Addition of $30\;{\mu}M\;H_2O_2$ enhanced amylase release caused by 10 pM CCK-8S, but inhibited the amylase release induced by CCK-8S at concentrations higher than 100 pM. An ROS scavenger, $10\;{\mu}M$ Mn(III)tetrakis(4-benzoic acid)porphyrin chloride, increased amylase release caused by CCK-8S at concentrations higher than 100 pM, although lower concentrations of CCK-8S-induced amylase release was not affected. To examine whether the effect of $H_2O_2$ on CCK-8S-induced amylase release was exerted via modulation of intracellular $Ca^{2+}$ signaling, we measured the changes in intracellular $Ca^{2+}$ concentration $([Ca^{2+}]_i)$ in fura-2 loaded acinar cells. Although $30\;{\mu}M\;H_2O_2$ did not induce any increase in $[Ca^{2+}]_i$ by itself, it increased the frequency and amplitude of $[Ca^{2+}]_i$ oscillations caused by 10 pM CCK-8S. However, $30\;{\mu}M\;H_2O_2$ had little effect on 1 nM CCK-8S-induced increase in $[Ca^{2+}]_i$. ROS scavenger, 1 mM N-acetylcysteine, did not affect $[Ca^{2+}]_i$ changes induced by 10 pM or 1 nM CCK-8S. Therefore, it was concluded that $30\;{\mu}M\;H_2O_2$ enhanced low concentration of CCK-8S-induced amylase release probably by increasing $[Ca^{2+}]_i$ oscillations while it inhibited high concentration of CCK-8S-induced amylase release.

Effects of pH, $PCO_2$, and Adenosine on the Contractility of Pig Coronary Artery

  • Chang, Seok-Jong;Kim, Il-Seon;Jeon, Byeong-Hwa;Kim, Se-Hoon
    • The Korean Journal of Physiology
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    • v.26 no.1
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    • pp.45-54
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    • 1992
  • Effects of pH, $PCO_2$, and adenosine on the vascular contractility were investigated in the pig coronary arteries. The helical strips of isolated coronary arteries were immersed in the HEPES or $HCO_3^-/CO_2$-buffered Tyrode's solution equilibrated with 100% $O_2\;or\;95%\;O_2-5%\;CO_2\;at\;35^{\circ}C$. The contraction was recorded isometrically using a force transducer. The amplitudes of contraction induced by ACh, high $K^+$, and electrical Held stimulation (EFS) were decreased by elevating extracellular pH (pHo) and were increased by lowering pHo. A shift from $0%\;CO_2\;to\;5%\;CO_2$ at constant pHo (pH 7.4) reduced the contractions induced by ACh, high $K^+$, EFS. However the contraction induced by 100mM $K^+$ was less influenced by the change of pHo or $CO_2$. The contraction induced by ACh in $Ca^{2+}$free Tyrode's solution as well as the contraction developed by the addition of extracellular of $Ca^{2+}$ were decreased by lowering pHo and were increased by elevating pHo. High $K^+$ (25mM) induced contraction at pH 6.8 was not returned to the level of the contraction at pH 7.4 by the elevation of extracellular. calcium $[Ca^{2+}]_o$. Adenosine-induced relaxation was more significant with 5% $CO_2$ than 0% $CO_2$ in the high $K^+$-induced contraction and was more significant with low pHo than high pHo in the contraction induced by EFS. From the above results, it is suggested that $H^+$ and $CO_2$ inhibit $Ca^{2+}$ influx as well as $Ca^{2+}$ release from intracellular $Ca^{2+}$ storage sites and enhance the relaxing effect of adenosine in the pig coronary artery.

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Ginsenoside Rg3 reduces the adhesion, invasion, and intracellular survival of Salmonella enterica serovar Typhimurium

  • Mechesso, Abraham F.;Quah, Yixian;Park, Seung-Chun
    • Journal of Ginseng Research
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    • v.45 no.1
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    • pp.75-85
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    • 2021
  • Background: Invasive infections due to foodborne pathogens, including Salmonella enterica serovar Typhimurium, are prevalent and life-threatening. This study aimed to evaluate the effects of ginsenoside Rg3 (Rg3) on the adhesion, invasion, and intracellular survival of S. Typhimurium. Methods: The impacts of Rg3 on bacterial growth and host cell viability were determined using the time kill and the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assays, respectively. Gentamicin assay and confocal microscopic examination were undertaken to determine the effects of Rg3 on the adhesive and invasive abilities of S. Typhimurium to Caco-2 and RAW 264.7 cells. Quantitative reverse transcription polymerase chain reaction was performed to assess the expression of genes correlated with the adhesion, invasion, and virulence of S. Typhimurium. Results: Subinhibitory concentrations of Rg3 significantly reduced (p < 0.05) the adhesion, invasion, and intracellular survival of S. Typhimurium. Rg3 considerably reduced (p < 0.05) the bacterial motility as well as the release of nitrite from infected macrophages in a concentration-dependent manner. The expression of genes related to the adhesion, invasion, quorum sensing, and virulence of S. Typhimurium including cheY, hilA, OmpD, PrgK, rsgE, SdiA, and SipB was significantly reduced after Rg3 treatment. Besides, the compound downregulated rac-1 and Cdc-42 that are essential for actin remodeling and membrane ruffling, thereby facilitating Salmonella entry into host cells. This report is the first to describe the effects of Rg3 on "trigger" entry mechanism and intracellular survival S. Typhimurium. Conclusion: Rg3 could be considered as a supplement agent to prevent S. Typhimurium infection.

Functional and Physical Interaction between Human Lactate Dehydrogenase B and $Na^+/H^+$ Exchanger Isoform 1

  • Kim, Eun-Hee
    • Animal cells and systems
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    • v.13 no.3
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    • pp.283-288
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    • 2009
  • The ubiquitous plasma membrane $Na^+/H^+$ exchanger 1 (NHE1) is rapidly activated in response to various extracellular stimuli and maintains normal cytoplasmic pH. Yeast two-hybrid screening was used in order to identify proteins interacting with NHE1 using its cytoplasmic domain as a bait from HeLa cDNA library. One of the interacting cDNA clones was human Lactate dehydrogenase B (LDHB). In vitro translated LDHB was pulled down together with GST-NHE1.cd protein in the GST pull down assay, confirming the interaction in vitro. LDHB antibody immunoprecipitated endogenous LDHB together with NHE1 from H9c2 cells, validating cellular interaction between NHE1 and LDHB. Subsequent analysis revealed that the overexpression of LDHB increased intracellular PH, implying opening of the NHE1 transporter. Moreover, overexpression of LDHB activated caspase 3 and induced cell death, consistent with the expected phenotype of hyper-activation of NHE1. Collectively, our data indicate that LDHB modulates NHE1 activity via physical interaction.

General Properties of Phytase Produced by Fluorescent Pseudomonas sp. BUN1 (토양세균 Fluorescent Pseudomonas sp. BUN 1 균주 유래의 파이테이즈(Phytase)의 일반적 특성규명)

  • Cho, Jaie-Soon
    • Journal of Animal Science and Technology
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    • v.51 no.2
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    • pp.171-176
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    • 2009
  • A bacterial strain producing intracellular phytase was isolated from cultivable soil near cowsheds and identified as a fluorescent Pseudomonas sp. BUN1. The BUN1 phytase, partially purified by cation and anion exchange chromatography, exhibited its optimal activity at $40^{\circ}C$ and pH 5.5. As for substrate specificity, it was very specific for phytate and showed little activity on other phosphorylated conjugates. Its activity was greatly inhibited by metal ions such as $Cu^{2+}$, $Cd^{2+}$, and $Zn^{2+}$. Addition of corn starch to PSM (phytasesynthetic medium) [0.5% sodium phytate, 0.5% $(NH_4)_2SO_4$, 0.5% KCl, 0.01% $MgSO_4\cdot7H_2O$, 0.01% $CaCl_2\cdot2H_2O$, 0.01% NaCl, 0.001% $FeSO_4\cdot7H_2O$, 0.001% $MnSO_4\cdot4H_2O$; pH 6.5] for the phytase production significantly induced its enzyme activity in comparison with other carbon sources tested.