• Journal of Life Science
• /
• v.26 no.2
• /
• pp.155-163
• /
• 2016

Metabolism of lactate dehydrogenase (EC 1.1.1.27, LDH) was studied to identify the function of LDH-C. Tissues of LDH liver-specific Ldh-C expressed Carassius auratus and eye-specific Ldh-C expressed Lepomis macrochirus after starvation were studied. LDH activity in liver tissue from C. auratus was increased after starvation. And LDH specific activity (units/mg) and LDH/CS were increased in tissues. It means the anaerobic metabolism was taking place in C. auratus after starvation. LDH B₄ isozyme was decreased in skeletal muscle and increased in heart tissue. LDH C₄ isozymes those showed in eye and brain tissues were identified as liver-specific C₄ isozymes and disappeared after starvation. And C hybrid in eye, A₄ isozyme in brain, and both C hybrid and C₄ isozyme in liver tissue were increased, respectively. In L. macrochirus, the level of variation of LDH activities was low but greatly increased especially in eye tissue and LDH A₄ and AC hybrid were increased in brain tissue. The LDH activities in tissues from C. auratus and L. macrochirus remained 30.30-18.64% and 25-18.75%, respectively, as a result of the inhibition by 10 mM of pyruvate. The Km^PYR values of LDH in C. auratus were increased. As a result, LDH liver-specific C₄ isozyme was expressed in liver, brain and eye tissues during starvation. It seems metabolism of lactate was predominant in brain tissue. After starvation, the liver-specific LDH-C was affected more than eye-specific LDH-C.

• Journal of Life Science
• /
• v.31 no.12
• /
• pp.1066-1071
• /
• 2021

The aim of this study was to examine the metabolic adjustment of lactate dehydrogenase (EC 1.1.1.27, LDH) isozymes to a change in dissolved oxygen (DO) in bluegill (Lepomis macrochirus). After bluegills were adapted to a constant environment in an aquarium, the DO was changed to investigate the activity of LDH isozyme and the relative ratio of subunits A, B, and C for each tissue. When the DO was decreased from 18 ppm to 6 ppm, LDH in skeletal muscle, heart, and brain tissues recovered to the level of control activity within 12, 12, and 6 hr, respectively. LDH activity changed in accordance with a change in DO. The compensation was performed rapidly and is thought to be an important function of LDH in enabling bluegills to adapt to their environment. In bluegill heart, eye, and brain tissues, the relative ratio of subunit A increased and showed a tendency to recover similarly to the subunit ratio of control groups up to 12 hr. It is thought that the anaerobic metabolism using subunit A was increased in the initial stage when DO was changed. In addition, the results revealed that subunit C was more similar to subunit A than subunit B. In bluegills, subunits A and C of LDH seem to be evolutionarily similar. LDH isozymes, mainly containing subunits A and C, are likely responsible for the function of pyruvate reductase, which plays a role in making the bluegill adapt to a hypoxic environment through anaerobic metabolism.

• Journal of Microbiology and Biotechnology
• /
• v.9 no.1
• /
• pp.84-90
• /
• 1999

The growth of Bifidobacterium breve strain HP2 was completely inhibited by the addition of lactate higher than 4.0％ but not by the addition of acetate. Two kinds of lactate-tolerant mutants were isolated by the nitrosoguanidine treatment, enrichment on a liquid medium with 5％ lactate, and selection on agar plates with 5％ lactate. The mutants were not only able to grow in the presence of 5％ lactate but also improved in viable cell stability in the acidic pH range. In a pH-controlled fermentor, mutant N-1-5 grew at a rate slower than that of the wild type but its growth yield was higher. Notably, mutants were more halotolerant and more osmotolerant than the wild type and they were able to grow in the presence of 3％ NaCl or 25％ lactose at which the wild type entirely stopped the growth. The enzyme activities involved in the lactose metabolism in B. breve were measured to elucidate the biochemical basis for lactate tolerance. In the mutants, activities of several enzymes including phosphoglucomutase decreased compared to the wild-type, which may explain their lower growth rate. However, the activity of lactate dehydrogenase or its nature of inhibition by lactate was not altered.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.20 no.3
• /
• pp.81-90
• /
• 2007

Purpose: This study was conducted to investigate the muscle anti-fatigue effects of Allii tuberosi semen after long term administration. Materials and Methods: 4-6 weeks old ICR mice were used in this study and we administered the water soluble extracts of Allii tuberosi semen in the concentration of 1, 10 and 100mg/0.3ml to each 5 mice (ATS group) and same volume of normal saline was administered to 5 mice (control group) once a day for 90 or 120 days. After the administration we performed the swimming exercise test and the grip strength test. And we measured the concentration of glucose and the activity of lactate dehydrogenase in plasma regarded as biochemical indicator related with the muscular fatigue. Results: In swimming exercise test, all ATS groups showed increased time compared with relative control group after 90 days administration. But after 120 days adminstration 10 and 100mg/0.3ml ATS groups showed increased results. In grip strength test, all ATS group increased grip strength after 90 days administration and 10mg/0.3ml ATS group showed increased result after 120 days administration. All the results of plasma glucose didn't showed statistically significant difference after 90 and 120 days administration. In the plasma concentration of activity level of lactate dehydrogenase, 1mg/0.3ml and 10mg/0.3ml ATS groups showed decreased concentration compared with relative control group after 90 days administration. But after 120 days adminstration 1mg/0.3ml ATS groups showed decreased results. Conclusion: From this study we could find the anti-fatigue effect of Allii tuberosi semen in the muscle strength related test.

• Fisheries and Aquatic Sciences
• /
• v.2 no.2
• /
• pp.167-171
• /
• 1999

This study was designed to develop biomarkers of coastal pollution using biochemical indices of flounder (Paralichthys olivaceus) by changes in lactate dehydrogenase (LDH) activity in the serum and cholinesterase activities in brain membranes. For this purpose acetylcholiesterase (AChE) activity, butyrylcholinesterase (BChE) activity, LDH/AChE ratio and LDH/BChE ratio of cultured flounders at 5 different sites on the southern coast of Korea were compared to those of wild flounders caught in the Pohang, eastern coast of Korea as a control group. Relatively high LDH activities were measured in the serum of flounders cultured on the southern coast of Korea (0.101-0.145 unit) than those in the Pohang control group (0.093 unit). AChE activities were significantly low $(about\;10-20\%)$ in brain membranes of cultured flounders compared to those in the Pohang control group. The ratios of LDH/AChE and LDH/BChE were consistently higher $(136-178\%,\; 155-214\%)$ in cultured flounders than those of Pohang control group. Thus, we propose that the ratios of LDH/AChE and LDH/BChE in flounders could be applicable for the diagnosis of marine pollution.

• Animal cells and systems
• /
• v.13 no.3
• /
• pp.283-288
• /
• 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.

• 한국생물공학회:학술대회논문집
• /
• 2003.10a
• /
• pp.692-695
• /
• 2003

In this work immobilization technique of enzymes onto the magnetic nanoparticles has been developed for biochip applications. Glucose oxidase and lactate dehydrogenase were immobilized on magnetic nanoparticles via cyanamide and glutaraldehyde. Immobilized enzymes had good operational and storage stability The immobilized glucose oxidase and lactate dehydrogenase were characterized by some factors(pH, temperature, and components of buffer solution etc) which affect the activity, In order to characterize the magnetic nanoparticles, we have used transmission electron microscopy(TEM), X-ray diffraction(XRD) and Fourier transform infrared(FTIR).

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.29 no.2
• /
• pp.193-197
• /
• 2000

The effects of black soybena extracts on enzymes activies of rat were evaluated in present study. Eighty-four male Sprague-Dawley rats weighing 100$\pm$10g were divided into twelve groups which consisted of black soybean extract, Pb and Cd solution, and black soybean extract plus Pb or Cd soln groups. The weight gain was increased in black soybean extracts and Pb soln solution group but decreased in Cd soln solution group. The results obtained form the experiment were as follows: Glutamate pyruvate trasaminase (GPT) and glutamate oxaloacetate oxaloacetate transaminase (GOT) activities were not significantly different among experimental groups. The lactate dehydrogenase (LDH) activities of black soybean extract administered groups were decreased than those of Pb and Cd solution group. Black soybean group increased cholinesterase (ChEase) activity as compared to administration of Pb and Cd soln group.

• YAKHAK HOEJI
• /
• v.39 no.5
• /
• pp.528-534
• /
• 1995

This investigation was aimed at the study of the antidiabetic activity and effect on hepatic glutathione metabolism of polysaccharide from Trichosanthes kirilowii in hyperglycemic rats with aboxan (175 mg/Kg, i.p.). As the results, the polysaccharide inhibited the increase of blood glucose, triglyceride level and lactate dehydrogenase activity, but cholesterol not changed. And it increased protein bound-SH, nonprotein bound-SH, glutathione level and inhibited the decrease of glutathione S-transferase.

• Journal of Life Science
• /
• v.24 no.2
• /
• pp.118-127
• /
• 2014

The kinetic properties and isozyme expression of lactate dehydrogenase (EC 1.1.1.27; LDH) in tissues from Rana catesbeiana I and II collected from February (I) and August (II) were studied. LDH activities, A4 isozyme, and LDH/citrate synthase (EC 4.1.3.7; CS) were high in skeletal muscle from R. catesbeiana I, and LDH $B_4$ isozyme increased in several tissues of R. catesbeiana II. In particular, LDH activities were high in heart and brain tissues from R. catesbeiana II. LDH eye-specific C isozyme, detected by native polyacrylamide gel electrophoresis after immunoprecipitation, was expressed in eye tissue and was more similar to the $B_4$ than $A_4$ isozyme. LDH $A_4$ isozyme was purified by oxamate-linked affinity chromatography, and the molecular weight of subunit A was 32.0 kDa. In R. catesbeiana II, levels of $Km^{PYU}$, $Vmax^{LAC}$, and tolerance to lactate of LDH were high in all tissues, and $Vmax^{PYU}$ of LDH in heart and brain tissue was highly detected. Purified $A_4$ isozyme and LDH in eye tissue were highly tolerate compared to others. The $Km^{LAC}$ value was highly measured compared to $Km^{PYU}$. The degree of inhibition by 10 mM of pyruvate on LDH activities in tissues from R. catesbeiana I and II was more pronounced as the ratio of subunit B increased. As a result, characteristic expression of LDH eye-specific C was found in R. catesbeiana. Anaerobic metabolism seemed to predominate as the LDH of skeletal muscle from I showed higher activity. It also appeared that R. catesbeiana II adapted well to incremental increases in LDH B, becoming tolerant to the lactate of LDH in tissues.