Reduction of d-lactate content in sauerkraut using starter cultures of recombinant Leuconostoc mesenteroides expressing the ldhL gene

Jin, Q.,Li, L.,Moon, J.S.,Cho, S.K.,Kim, Y.J.,Lee, S.J.,Han, N.S. Society for Bioscience and Bioengineering, Japan ; 2016 Journal of bioscience and bioengineering Vol.121 No.5

<P>The n-form of lactate, which causes metabolic stress upon excessive dietary intake, is mainly produced by Leuconostoc sp., the predominant species in sauerkraut. To shift the metabolic flux of D-lactate from pyruvate to L-lactate, we expressed the L-lactate dehydrogenase (ldhL) gene in Leuconostoc mesenteroides ATCC 8293. The IdhL gene from Lactobacillus plantarum was introduced into L. mesenteroides using the shuttle vectors pLeuCM and pLeuCM42. To elevate the expression level of IdhL in L. mesenteroides, the nucleotides for pyruvate kinase promoter were fused to IdhL and cloned into above vectors to construct pLC18pkL and pLC42pkL. As results, introduction of pLC42pkL in L. mesenteroides significantly improved both L-LDH activity and L-lactate productivity during fermentation, decreasing the D-/L-lactate ratio. When used as a starter culture for sauerkraut fermentation, recombinant L. mesenteroides harboring pLC42pkL increased L-lactate concentration and decreased D-lactate concentration compared to the wild type strain. We newly developed a recombinant L. mesenteroides which has high L-lactate dehydrogenase activity and applied this strain to minimize the harmful effect of D-lactate during the sauerkraut fermentation. To the best of our knowledge, we demonstrate for the first time the effective use of recombinant Leuconostoc sp. for quality improvement of fermented foods. (C) 2015, The Society for Biotechnology, Japan. All rights reserved.</P>

Effects of the novel angiotensin II receptor type I antagonist, fimasartan on myocardial ischemia/reperfusion injury

Han, J.,Park, S.J.,Thu, V.T.,Lee, S.R.,Long, L.T.,Kim, H.K.,Kim, N.,Park, S.W.,Jeon, E.S.,Kim, E.J.,Yoon, C.H.,Cho, G.Y.,Choi, D.J. Elsevier/North-Holland Biomedical Press 2013 INTERNATIONAL JOURNAL OF CARDIOLOGY Vol.168 No.3

Background: The aim of this study was to investigate the cardioprotective effect of fimasartan, a newly developed angiotensin II receptor type I blocker (ARB), against myocardial ischemia/reperfusion (I/R) injury and to identify the mechanism by which it reduces mitochondrial damage. Methods: Fimasartan was administered intravenously to Sprague-Dawley rats (3mg/kg), cardiomyocytes (50μM), and H9c2 cells (50μM) before ischemia or hypoxia. Myocardial infarction (MI), echocardiograms, DNA fragmentation, terminal deoxynucleotidyl transferase-mediated dUTP in situ nick-end labeling, immunoblotting, oxygen consumption, confocal microscopic appearance, and L-type Ca<SUP>2+</SUP> current (I<SUB>Ca,L</SUB>) were then assessed. Results: Fimasartan pretreatment remarkably reduced the rate of MI and improved cardiac performance well after I/R (n=9/group). Fimasartan also reduced apoptotic cell death both in vivo and in hypoxia/reoxygenation (H/R)-treated H9c2 cells (n=5~8/group). H/R-induced mitochondrial O<SUB>2</SUB><SUP>-</SUP> production and collapse of membrane potential were markedly attenuated in fimasartan-treated cardiomyocytes (n=4~6/group). Additionally, mitochondrial Ca<SUP>2+</SUP> overload during reoxygenation was suppressed by fimasartan (n=4~6/group), and this was found to be possibly related to the inhibition of I<SUB>Ca,L</SUB> and mitochondrial Ca<SUP>2+</SUP> uniporter. Furthermore, fimasartan pretreatment increased phosphorylations of Akt and glycogen synthase kinase-3β (n=5~7/group), decreased pro-apoptotic p53 levels, and increased anti-apoptotic Bcl-2 levels (n=4) during reperfusion. Conclusions: Fimasartan preconditioning has the potential to modulate Bcl-2 and suppress I/R-induced Ca<SUP>2+</SUP> overload by inhibiting I<SUB>Ca,L</SUB> and MCU. These beneficial effects could prevent the mitochondrial dysfunction and apoptosis accompanied by I/R.

Therapeutic mechanisms and beneficial effects of non-antidiabetic drugs in chronic liver diseases

Han Ah Lee,Young Chang,Pil Soo Sung,Eileen L. Yoon,Hye Won Lee,Jeong-Ju Yoo,Young-Sun Lee,Jihyun An,Do Seon Song,Young Youn Cho,Seung Up Kim,Yoon Jun Kim 대한간학회 2022 Clinical and Molecular Hepatology(대한간학회지) Vol.28 No.3

The global burden of chronic liver disease (CLD) is substantial. Due to the limited indication of and accessibility to antiviral therapy in viral hepatitis and lack of effective pharmacological treatment in nonalcoholic fatty liver disease, the beneficial effects of antidiabetics and non–antidiabetics in clinical practice have been continuously investigated in patients with CLD. In this narrative review, we focused on non-antidiabetic drugs, including ursodeoxycholic acid, silymarin, dimethyl- 4,4’-dimethoxy-5,6,5’,6’-dimethylenedixoybiphenyl-2,2’-dicarboxylate, L-ornithine L-aspartate, branched chain amino acids, statin, probiotics, vitamin E, and aspirin, and summarized their beneficial effects in CLD. Based on the antioxidant, anti-inflammatory properties, and regulatory functions in glucose or lipid metabolism, several non–antidiabetic drugs have shown beneficial effects in improving liver histology, aminotransferase level, and metabolic parameters and reducing risks of hepatocellular carcinoma and mortality, without significant safety concerns, in patients with CLD. Although the effect as the centerpiece management in patients with CLD is not robust, the use of these non-antidiabetic drugs might be potentially beneficial as an adjuvant or combined treatment strategy.

Differentiation efficiency of induced pluripotent stem cells depends on the number of reprogramming factors.

L?hle, Matthias,Hermann, Andreas,Glass, Hannes,Kempe, Andrea,Schwarz, Sigrid C,Kim, Jeong Beom,Poulet, Claire,Ravens, Ursula,Schwarz, Johannes,Sch?ler, Hans R,Storch, Alexander AlphaMed Press 2012 Stem cells Vol.30 No.3

<P>Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) by retroviral overexpression of the transcription factors Oct4, Sox2, Klf4, and c-Myc holds great promise for the development of personalized cell replacement therapies. In an attempt to minimize the risk for chromosomal disruption and to simplify reprogramming, several studies demonstrated that a reduced set of reprogramming factors is sufficient to generate iPSC, albeit at lower efficiency. To elucidate the influence of factor reduction on subsequent differentiation, we compared the efficiency of neuronal differentiation in iPSC generated from postnatal murine neural stem cells with either one (Oct4; iPSC(1F-NSC) ), two (Oct4, Klf4; iPSC(2F-NSC) ), or all four factors (iPSC(4F-NSC) ) with those of embryonic stem cells (ESCs) and iPSC produced from fibroblasts with all four factors (iPSC(4F-MEF) ). After 2 weeks of coculture with PA6 stromal cells, neuronal differentiation of iPSC(1F-NSC) and iPSC(2F-NSC) was less efficient compared with iPSC(4F-NSC) and ESC, yielding lower proportions of colonies that stained positive for early and late neuronal markers. Electrophysiological analyses after 4 weeks of differentiation identified functional maturity in neurons differentiated from ESC, iPSC(2F-NSC) , iPSC(4F-NSC) , and iPSC(4F-MEF) but not in those from iPSC(1F-NSC) . Similar results were obtained after hematoendothelial differentiation on OP9 bone marrow stromal cells, where factor-reduced iPSC generated lower proportions of colonies with hematoendothelial progenitors than colonies of ESC, iPSC(4F-NSC) , and iPSC(4F-MEF) . We conclude that a reduction of reprogramming factors does not only reduce reprogramming efficiency but may also worsen subsequent differentiation and hinder future application of iPSC in cell replacement therapies.</P>

A Pan-Cancer Analysis of Enhancer Expression in Nearly 9000 Patient Samples

Chen, Han,Li, Chunyan,Peng, Xinxin,Zhou, Zhicheng,Weinstein, John N.,Caesar-Johnson, Samantha J.,Demchok, John A.,Felau, Ina,Kasapi, Melpomeni,Ferguson, Martin L.,Hutter, Carolyn M.,Sofia, Heidi J.,Ta Elsevier 2018 Cell Vol.173 No.2

<P><B>Summary</B></P> <P>The role of enhancers, a key class of non-coding regulatory DNA elements, in cancer development has increasingly been appreciated. Here, we present the detection and characterization of a large number of expressed enhancers in a genome-wide analysis of 8928 tumor samples across 33 cancer types using TCGA RNA-seq data. Compared with matched normal tissues, global enhancer activation was observed in most cancers. Across cancer types, global enhancer activity was positively associated with aneuploidy, but not mutation load, suggesting a hypothesis centered on “chromatin-state” to explain their interplay. Integrating eQTL, mRNA co-expression, and Hi-C data analysis, we developed a computational method to infer causal enhancer-gene interactions, revealing enhancers of clinically actionable genes. Having identified an enhancer ∼140 kb downstream of PD-L1, a major immunotherapy target, we validated it experimentally. This study provides a systematic view of enhancer activity in diverse tumor contexts and suggests the clinical implications of enhancers.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Systematic analysis of enhancer expression across ∼9,000 samples of 33 cancer types </LI> <LI> Global enhancer activation positively correlates with aneuploidy but not mutations </LI> <LI> A computational method that infers causal enhancer-target-gene relationships </LI> <LI> Enhancers as key regulators of therapeutic targets, including PD-L1 </LI> </UL> </P> <P><B>Graphical Abstract</B></P> <P>[DISPLAY OMISSION]</P>

Effects of Expander Operating Conditions on Nutrient Digestibility in Finishing Pigs

S.L., Traylor,K.C., Behnke,J.D., Hancock,R.H., Hines,S.L., Johnston,B.J., Chae,In K., Han Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.3

Five experiments were conducted using finishing pigs (PIC L326 sires $\times$ C15 dams) to examine the effects of expander operating conditions on nutrient digestibility in finishing pigs. The effects of different expanding conditions (0, 11.7, 24.4, $32.5kg/cm^2$) for corn-SBM based diets (Exp. 1), wheat meddlings diet (Exp. 2), sorghum-SBM based diets (Exp. 3) and wheat-SBM based diet (Exp. 4). Exp. 5 was conducted as a $2{\times}4$ factorial arrangement and factors examined were 2 soy products (raw soybean and SBM) and 4 expanding conditions (0, 14.1, 28.1, $42.2kg/cm^2$). In experiment 1, total production rates (p>0.10) were similar among treatments. The amount of fines decreased (cubic effect, p<0.001) as cone pressure was increased from 0 to $11.7kg/cm^2$, with smaller differences as cone pressure was further increased to $35.2kg/cm^2$. Nutrient digestibilities increased (p<0.02) as the feed was subjected to higher cone pressures. Digestibilities of DM, N, and GE were maximized at $24.4kg/cm^2$ cone pressure. The DE of the diet expanded at 24.4 and $35.2kg/cm^2$ increased by 172 and 109 kcal/kg, respectively, compared to the diet processed at $0kg/cm^2$ cone pressure. In experiment 2, total production and screened pellets production rates were similar among the processing treatments (p>0.21). The amount of fines decreased (quadratic effect, p<0.03) by 9 kg/h as cone pressure was increased from 0 to $11.7kg/cm^2$. Digestibilities of DM (p<0.02), N (p<0.001), and GE (p<0.002) were increased as cone pressure was increased from 0 to $35.2kg/cm^2$. DM, N, and GE digestibility in the pigs fed the midds-based diet increased by 8, 13, and 10%, respectively, at the highest processing cone pressure compared to the diets without any cone pressure. In experiment 3, the conditioned mash moistures for the treatments were numerically similar around 15% moisture. As the expander cone pressure was increased from 0 to $11.7kg/cm^2$, energy consumption for the pellet mill decreased (quadratic effect, p<0.004) from 14.1 to 12.0 kWh/t. Dry matter and gross energy digestibility increased (cubic effects, p<0.006) as cone pressure was increased from 0 to $35.2kg/cm^2$ with the largest improvement occurring as cone pressure was increased from 0 to $11.7kg/cm^2$. Nitrogen digestibility increased (cubic effect, p<0.001) from 78.3 to 81.0% as the feed was subjected to the higher cone pressures, with N digestibility being maximized at $24.4kg/cm^2$ cone pressure. The DE of the diet increased (cubic effect, p<0.001) by 225 kcal/kg as cone pressure was increased from 0 to $11.7kg/cm^2$. In experiment 4, pellet moisture decreased and moisture loss increased as cone pressure was increased from 0 to $35.2kg/cm^2$. Also, starch gelatinization of the wheat-based diets increased from 16.8 to 49.1% as the diets were processed at 0 and $35.2kg/cm^2$ cone pressure. Nutrient digestibilities were not affected (p>0.18) by any increase in cone pressure. In experiment 5, pellet moisture decreased as cone pressure was increased 0 to $35.2kg/cm^2$. The amount of moisture loss for the diets expanded at $42.2kg/cm^2$ was 3.0 and 3.8% for the SBM and raw soybean (RB) diets, respectively. Starch gelatinization for the SBM diets were 19% greater than the RB diets. The RB diets had lower DM, N and GE digestibilities as compared to the SBM diets. The DE of the RB diets were lower (p<0.02) than the SBM diets. DM (p<0.06), N (p<0.02), and GE (p<0.001) digestibilities of the dietary treatments increased as cone pressure was increased 0 to $42.2kg/cm^2$.

Characterization of the major dehydrogenase related to d-lactic acid synthesis in Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293

Li, L.,Eom, H.J.,Park, J.M.,Seo, E.,Ahn, J.E.,Kim, T.J.,Kim, J.H.,Han, N.S. IPC Science and Technology Press ; Elsevier Scienc 2012 Enzyme and microbial technology Vol.51 No.5

Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293 is a lactic acid bacterium that converts pyruvate mainly to d-(-)-lactic acid by using d-(-)-lactate dehydrogenase (ldhD). The aim of this study was to identify the gene responsible for d-lactic acid formation in this organism and to characterize the enzyme to facilitate the production of optically pure d-lactic acid. A genomic analysis of L. mesenteroides ATCC 8293 revealed that 7 genes encode lactate-related dehydrogenase. According to transcriptomic, proteomic, and phylogenetic analyses, LEUM_1756 was the major gene responsible for the production of d-lactic acid. The LEUM_1756 gene, of 996bp and encoding 332 amino acids (36.5kDa), was cloned and overexpressed in Escherichia coli BL21(DE3) Star from an inducible pET-21a(+) vector. The enzyme was purified by Ni-NTA column chromatography and showed a specific activity of 4450U/mg, significantly higher than those of other previously reported ldhDs. The gel permeation chromatography analysis showed that the purified enzyme exists as tetramers in solution and this was the first report among lactic acid bacteria. The pH and temperature optima were pH 8.0 and 30<SUP>o</SUP>C, respectively, for the pyruvate reduction reaction, and pH 11.0 and 20<SUP>o</SUP>C, respectively, for the lactate oxidation reaction. The K<SUB>m</SUB> kinetic parameters for pyruvate and lactate were 0.58mM and 260mM, respectively. In addition, the k<SUB>cat</SUB> values for pyruvate and lactate were 2900s<SUP>-1</SUP> and 2280s<SUP>-1</SUP>, respectively. The enzyme was not inhibited by Ca<SUP>2+</SUP>, Co<SUP>2+</SUP>, Cu<SUP>2+</SUP>, Mg<SUP>2+</SUP>, Mn<SUP>2+</SUP>, Na<SUP>+</SUP>, or urea, but was inhibited by 1mM Zn<SUP>2+</SUP> and 1mM SDS.

Effect of Potassium Silicate Amendments in Hydroponic Nutrient Solution on the Suppressing of Phytophthora Blight (Phytophthora capsici) in Pepper

Seo, Sang-Tae,Wang, T.C.,Jang, Han-Ik,Pae, Do-Ham,Engle, L.M.,Lee, Jung-Sup The Korean Society of Plant Pathology 2004 Plant Pathology Journal Vol.20 No.4

Amendments of a recirculating nutrient solution with potassium silicate were evaluated as a means to control Phytophthora capsici infections on pepper plant(Capsicum annuum L.). Supplying the solutions with 100 or 200 ppm of silicate significantly reduced motility, root decay, and yield losses attributed to infection of P. capsici. Treating inoculated plants with potassium silicate increased root dry weights and number of fruit, especially high-grade fruit. Results were slightly superior to non-inoculated controls. The two varieties, PBC 137 and PBC 602, responded similarly to the treatments. No significant differences were observed between the 100- and 200 ppm silicate treatments. Results were better when greenhouse conditions favored the spread of P. capsici. Silicon alone did not increase pepper yield, suggesting that it acts as a disease suppression agent rather than as a fertilizer, The phenomena by which silicon confers protection against P. capsici infection and disease development are not fully understood, but our results indicate that mechanisms other than a mechanical barrier to fungal penetration are involved.

Tetrahydropteridine deficiency impairs mitochondrial function in Dictyostelium discoideum Ax2

Kim, H.L.,Choi, Y.K.,Kim, D.H.,Park, S.O.,Han, J.,Park, Y.S. North-Holland Pub ; Elsevier Science Ltd 2007 FEBS letters Vol.581 No.28

A putative cellular function of tetrahydropteridines (l-erythro-tetrahydrobiopterin and d-threo-tetrahydrobiopterin) was investigated in Dictyostelium discoideum Ax2 using a mutant disrupted in the gene encoding sepiapterin reductase (SR). The SR mutant, which produces about 3% of tetrahydropteridines if compared to wild-type, was elucidated to have several functional defects related to mitochondria and oxidative stress: retarded growth, poor spore viability, impaired mitochondrial function, and increased susceptibility to oxidative stress induced by hydroxylamine or cumene-hydroperoxide. However, the physiological defects were almost completely rescued by extrachromosomal expression of Dictyostelium SR. The results strongly suggested that tetrahydropteridines in Dictyostelium are associated with mitochondrial function, probably via direct protection against oxidative stress.

Physics-based integrated modeling of the energy confinement time scaling laws for the H- and L-modes in the KSTAR-type tokamak model

Kim, J.Y.,Han, H.S.,Terzolo, L. International Atomic Energy Agency 2017 Nuclear fusion Vol.57 No.7

<P>In an effort to clarify the physics origin of the energy confinement time scaling law in H-mode plasmas, a new analysis method is first proposed where the stored energy is separated into two parts—one coming from the marginal stability with the pedestal boundary condition and the other related to the turbulent dynamics. The method is then applied for the analysis of the global scaling law, as initial examples, focusing on the four parameters of plasma current, input power, magnetic field and density in the KSTAR-type tokamak model. It is shown that the method can provide more quantitative and explicit information on how various physics elements, such as the linear stability, nonlinear turbulent dynamics and pedestal boundary, contribute to the global scaling factor. While this method is not directly applicable, the L-mode is also considered for comparison, trying to clarify how a difference in the scaling law can occur between the H- and L-modes.</P>