• Journal of Life Science
• /
• v.14 no.4
• /
• pp.702-707
• /
• 2004

In native-polyacrylamide gel electrophoresis of Pangasius polyuranodon, the lactate dehydrogenase (EC 1.1.1.27, LDH) $A_4$, $A_3$B, $A_2$$B_2$,$AB_3$ and $B_4$ isozymes were expressed in various tissues. The LDH $A_4$ and liver-specific $C_4$ isozymes were expressed in the tissues of Hypostomus Plecostomus. The bands of LDH in skeletal muscle, heart and eye tissues were not detected while one band was detected in kidney and liver, and four bands were detected in brain. The detected one band in liver was identified as alcohol dehydrogenase and an anodal band of skeletal muscle was identified as nothing dehydrogenase. The LDH in skeletal muscle, heart and eye might function as pyruvate reductase. The degree of inhibitions of LDH in skeletal muscle and heart of P. polyuranodon by 10 mM pyruvate were measured 57.6% and 73.8%, respectively. However, those of LDH in tissues of H. plecostomus were measured 52.7-61.8% so tissue specificity did not appear. Therefore, H. ple-costomus might be more acclimated to hypoxic environment by anaerobic metabolism of LDH iso-zymes than P. polyuranodon.

• BMB Reports
• /
• v.32 no.2
• /
• pp.140-146
• /
• 1999

When murine fibrosarcoma L929 cells, a TNF-sensitive cell line, were treated with recombinant human tumor necrosis factor-$\alpha$ (rhTNF-$\alpha$), the activities of glycolytic regulatory enzymes and lactate dehydrogenase increased up to 100-150% compared to the control L929 cells after TNF treatment. By using various metabolic inhibitors and activators, it was found that cAMP-dependent protein kinase is responsible for the increase of activities of the glycolytic enzymes. The activities of glycolytic regulatory enzymes and lactate dehydrogenase of TNF-resistant A549 cells, a human lung carcinoma cell line, did not increase significantly compared to TNF-sensitive L929 cells upon TNF treatment. In contrast, the pyruvate carboxylase activities of A549 cells, but not L929 cells, increased up to 30~40% after TNF treatment. The data suggest that pyruvate carboxylase activity may contribute to the compensation of energy loss mediated by TNF treatment in TNF-resistant A549 cells.

• BMB Reports
• /
• v.39 no.4
• /
• pp.426-431
• /
• 2006

Embryonic stem cells (ESCs), representing a population of undifferentiated pluripotent cells with both self-renewal and multilineage differentiation characteristics, are capable of spontaneous differentiation into cardiomyocytes. The present study sought to define the kinetic characterization of lactate dehydrogenase (LDH) and creatine kinase (CK) of ESC- and neonatal-derived cardiomyocytes. Spontaneously differentiated cardiomyocytes from embryoid bodies (EBs) derived from mouse ESC line (Royan B1) and neonatal cardiomyocytes were dispersed in a buffer solution. Enzymes were extracted by sonication and centrifugation for kinetic evaluation of LDH and CK with spectrophotometric methods. While a comparison between the kinetic properties of the LDH and CK of both groups revealed not only different Michaelis constants and optimum temperatures for LDH but also different Michaelis constants and optimum pH for CK, the pH profile of LDH and optimum temperature of CK were similar. In defining some kinetic properties of cardiac metabolic enzymes of ESC-derived cardiomyocytes, our results are expected to further facilitate the use of ESCs as an experimental model.

• Journal of Yeungnam Medical Science
• /
• v.5 no.2
• /
• pp.247-254
• /
• 1988

Serum lactate dehydrogenase isoenzymes are separated 5 fractions($LD_1-LD_5$) in normal serum by agrose electrophoresis. An unusual band on the cathodic side of $LD_5$ isoenzyme has been found on lactate dehydrogenase electrophores is of serum, called $LD_6$, and the presence of which signifies a poor prognosis for the patients of myocardial infarction. In recent, we have experienced $LD_6$ in two patients with myocardial infarction. Cardiac arrest was noted within 24 hours after exhibition of $LD_6$ extraband and they did not recover from their illness.

• Journal of Life Science
• /
• v.15 no.1 s.68
• /
• pp.100-105
• /
• 2005

The lactate dehydrogenase (EC 1.1.1.27, LDH) inhibitors were isolated from the LDH-free crude mitochondrial fraction of skeletal muscle in Syrian hamster (Mesocricetus auratus) and Korean native cattle (Bos taurus coreanae). The LDH inhibitor in skeletal muscle of M. auratus was successfully isolated by the treatment with 175 mM NaCl and ultrasonic. The LDH inhibitor in skeletal muscle of B. taurus coreanae was highly stable to heat and LDH fu isozyme was largely inhibited by the LDH inhibitor. The molecular weight of inhibitor was 22 kDa. Inhibitor played an important role in the binding of LDH with the mitochondria in tissues of skeletal muscle, kidney and liver except heart.

• Archives of Pharmacal Research
• /
• v.17 no.5
• /
• pp.343-347
• /
• 1994

Effects of betaine on glutamate-induced neurotoxicity were examined on primary culturs of chicken embryonic brain cells and on rat cortical cultures. Betaine was found to attenuate glutamate-induced neurotoxicity both morphologically and biochemically. A 30 min exposure of chicken embryonic brain cells cultured for 12 days to 500 .mu.M glutamate produced wide-spread acute neuronal swelling and neurtic fragmentation. A 2-h pretreatment of cultured chicken embryonic brain cells with i mM betaine prior to a 30 min exposure to 500 , mu, M glutamate significantly raised the survival rate of neurons in the culture. When chicken embryonic brain cells were pretreated for 2 h with i mM betaine followed by exposure to 100 .mu.M glutamate for 42 h, lactate dehydrogenase levels within the cells remained at 62% of .mu.M untreated control values while glutamate-treated control fell to 0% lactate dehydrogenase. Betaine also exerted attenuating effects on N-methyl-D-asparte-, kainate-and quisqualate-induced neurotoxicity in a similar manner to that observed with glutamate. Similar neuroprotective effects of betaine with rat cortical cultures.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.19 no.6
• /
• pp.1546-1551
• /
• 2005

This Study was designed to investigate the effects of Nelumbinis Rhizomatis Nodus (NRN) on the change of cerebral hemodynamics [regional cerebral blood flow (rCBF), pial arterial diameter (PAD) and mean arterial blood pressure (MABP)] in normal and cerebral ischemic rats. And, this study was designed to investigate the inhibition of lactate dehydrogenase activity in neuronal cells The results were as follows NRN significantly increased rCBF and PAD in a dose-dependent manner, and NRN increased MABP in a dose-dependent manner. This results suggested that NRN significantly increased rCBF by dilating PAD. Both rCBF and PAD were significantly and stably increased by NRN (10 mg/kg, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. NRN significantly inhibited lactate dehydrogenase activity in neuronal cells. This results suggested that NRN prevented the neuronal death. It is suggested that NRN had an anti-ischemic effect through the improvement of cerebral hemodynamics and inhibitive effect on the brain damage.

• Biomedical Science Letters
• /
• v.27 no.3
• /
• pp.170-176
• /
• 2021

Thapsigargin (TG), a sarco/endoplasmic reticulum (ER) Ca²⁺-ATPase (SERCA) inhibitor, has been widely used as an agonist for platelet aggregation for decades. In this study, we investigated the effect of TG on the release of lactate dehydrogenase (LDH) for platelets and elucidated its mechanism. Platelet LDH release and platelet aggregation were increased by TG treatment; 1,000 nM of TG induced the complete lysis of platelets. Other agonists such as collagen (2.5 ㎍/mL), thrombin (0.1 U/mL), and ADP (10 mM) did not induce significant platelet LDH release despite platelet aggregation. Finally, we investigated the effects of pharmacological inhibitors on TG-induced platelet aggregation and LDH release. SP600125, a JNK inhibitor, and LY294002, a PI-3K inhibitor, inhibited TG-induced platelet LDH release but not platelet aggregation. Forskolin, an adenylyl cyclase activator, also inhibited LDH release without affecting platelet aggregation by TG. These results suggest that the TG-induced platelet aggregation was accompanied by LDH release but regulated by a different signaling pathway.

• International journal of advanced smart convergence
• /
• v.11 no.4
• /
• pp.260-265
• /
• 2022

This study aimed to determine whether lactate dehydrogenase (LDH) levels in coronavirus disease (COVID-19) patients in Korea were higher than those in patients without COVID-19, and the effect of sex and age on LDH levels. A retrospective, observational study was conducted to measure LDH levels in 247 and 225 female and male COVID-19 patients, respectively, who were admitted to the study hospital between April 1 and October 30, 2020. Serum LDH levels were measured using an automated analyzer. Results: LDH levels were elevated in both male and female patients with COVID-19. Among patients with COVID-19, LDH levels were higher in males than in females, and LDH levels were higher in patients with COVID-19 than in patients in the control group. In the analysis of differences in LDH levels by age, LDH levels in patients with COVID-19 increased statistically significantly with age in males and females (males: p=0.001, females: p=0.001). By examining the differences in LDH levels according to sex and age, this study contributed to the basic biochemical data available in Korea, particularly regarding patients with COVID-19. Further research may be needed to examine confounding variables.

• Tuberculosis and Respiratory Diseases
• /
• v.87 no.1
• /
• pp.91-99
• /
• 2024

Background: Tuberculous pleural effusion (TPE) and parapneumonic effusion (PPE) are often difficult to differentiate owing to the overlapping clinical features. Observational studies demonstrate that the ratio of lactate dehydrogenase to adenosine deaminase (LDH/ADA) is lower in TPE compared to PPE, but integrated analysis is warranted. Methods: We conducted a systematic review to evaluate the diagnostic accuracy of the LDH/ADA ratio in differentiating TPE and PPE. We explored the PubMed and Scopus databases for studies evaluating the LDH/ADA ratio in differentiating TPE and PPE. Results: From a yield of 110 studies, five were included for systematic review. The cutoff value for the LDH/ADA ratio in TPE ranged from <14.2 to <25. The studies demonstrated high heterogeneity, precluding meta-analysis. Quality Assessment of Diagnostic Accuracy Studies Tool 2 assessment revealed a high risk of bias in terms of patient selection and index test. Conclusion: LDH/ADA ratio is a potentially useful parameter to differentiate between TPE and PPE. Based on the limited data, we recommend an LDH/ADA ratio cutoff value of <15 in differentiating TPE and PPE. However, more rigorous studies are needed to further validate this recommendation.