scholarly journals Mitochondrial proliferation in the permanent vs. temporary cold: enzyme activities and mRNA levels in Antarctic and temperate zoarcid fish

2003 ◽  
Vol 285 (6) ◽  
pp. R1410-R1420 ◽  
Author(s):  
M. Lucassen ◽  
A. Schmidt ◽  
L. G. Eckerle ◽  
H.-O. Pörtner
Keyword(s):  
Enzyme Activity ◽  
Enzyme Activities ◽  
Time Course ◽  
Citrate Synthase ◽  
Expression Patterns ◽  
Thermal Adaptation ◽  
Lipid Synthesis ◽  
Mrna Levels ◽  
Transcript Levels ◽  
Cold Adapted

Adjustments in mitochondrial properties and capacities are crucial in acclimatization to seasonal cold and in evolutionary cold adaptation of marine ectotherms. Although long-term compensatory increments in aerobic capacity of fish tissues have frequently been described in response to cold, much less is known about transitional phases and gene expression patterns involved. We investigated the time course of adjustment to acute cold in liver of eurythermal eelpout Zoarces viviparus. Whereas citrate synthase (CS) activity rose progressively in liver, cytochrome c oxidase (COX) activity was not altered during cold acclimation. Species-specific RNA probes were used to determine mRNA levels. CS mRNA (nuclear encoded) displayed a delayed, transient increase in response to cold, such that transcript levels did not parallel the change in enzyme activity. The enzyme activities and mRNA levels in the confamilial Antarctic Pachycara brachycephalum indicate cold compensation of CS activity in this cold-adapted species. The ratio of CS and COX activities was elevated in acclimation and adaptation to cold, indicating enhanced citrate synthesis over respiratory chain capacities in cold-adapted liver mitochondria. This may support enhanced lipid synthesis typically found in cold. The ratio of enzyme activity and transcript levels differed largely between Z. viviparus populations from the Baltic and North Seas, indicating the influence of unidentified parameters other than temperature. Transcript levels may not be tightly correlated with enzyme activities during thermal adaptation and thereafter. The time course of the acclimation process indicates that regulation at the translational and posttranslational levels predominates in adjustment to moderate thermal challenges.

scholarly journals Rat uterine microbiochemistry: metabolic enzyme activities stimulated by 17-beta-estradiol are localized in epithelial cells.

1987 ◽  
Vol 35 (6) ◽  
pp. 657-662 ◽  
Author(s):  
J P Holt ◽  
E Rhe
Keyword(s):  
Enzyme Activity ◽  
Smooth Muscle ◽  
Epithelial Cells ◽  
Dose Response ◽  
Enzyme Activities ◽  
Time Course ◽  
Citrate Synthase ◽  
Ovariectomized Rats ◽  
Similar Response ◽  
Estradiol Treatment

Lactate dehydrogenase (LDH; EC 1.1.1.27), citrate synthase (CS; EC 4.1.3.7), and beta-hydroxyacyl-CoA-dehydrogenase (beta-OH-acyl-CoA-DH; EC 1.1.1.35) activities were determined in each of the three major cell types of rat uterus, i.e., epithelial, stromal, and smooth muscle, using quantitative microanalytical techniques. Adult ovariectomized rats were treated with 17-beta-estradiol to determine the time course and dose response (0.025-50 micrograms/300-g rat) effect of estrogen on enzyme activity of each type of uterine cell. The use of "oil well" and enzyme-cycling microtechniques to determine the time course and the dose responses of enzyme activity changes required microassays involving 1595 microdissected single cell specimens. Estradiol treatment increased epithelial LDH, CS and beta-OH-acyl-CoA-DH activity but had no effect on these enzymes in the stroma or in smooth muscle cells. The estradiol-stimulated peak enzyme activities on Day 4 in the intervention group are compared with those in the ovariectomized rat controls as follows: LDH, 44.5 +/- 3.5 vs 22.3 +/- 3.9; CS, 3.5 +/- 0.2 vs 1.5 +/- 0.6; beta-OH-acyl-CoA-H, 3.5 +/- 0.32 vs 2.2 +/- 0.2 (mean +/- standard deviation; mol/kg/hr). Stromal cell activities (LDH, 7.4 +/- 1.0; CS, 1.2 +/- 0.2; beta-OH-acyl-CoA-DH, 0.9 +/- 0.1) were significantly lower than epithelial cell levels and were similar to smooth muscle levels. Therefore, even in the ovariectomized animal epithelial cells have markedly higher metabolic activity compared with adjacent cells. The enzyme activities are expressed as moles of substrate reacting per kilogram of dry weight per hour. All three enzymes exhibited a 17-beta-estradiol-induced dose response between 0.025-0.15 micrograms/300-g rat. The three enzymes studied all had similar response patterns to estrogen. The effect of estradiol was restricted to epithelial cells, with enzyme activities increasing to maximal levels after approximately 96 hr of hormone treatment. This study therefore not only confirms the specific and differential metabolic responses of uterine cells to estradiol treatment, but clearly demonstrates that marked metabolic differences exist between epithelial cells and stromal or smooth muscle uterine cells.

Citrate synthase expression and enzyme activity after endurance training in cardiac and skeletal muscles

2003 ◽  
Vol 94 (2) ◽  
pp. 555-560 ◽  
Author(s):  
Parco M. Siu ◽  
David A. Donley ◽  
Randall W. Bryner ◽  
Stephen E. Alway
Keyword(s):  
Gene Expression ◽  
Enzyme Activity ◽  
Enzymatic Activity ◽  
Endurance Training ◽  
Enzyme Activities ◽  
Citrate Synthase ◽  
Acute Effect ◽  
Mrna Levels ◽  
Adult Rats ◽  
Cardiac Muscles

The present study was designed to examine the acute and chronic effects of endurance treadmill training on citrate synthase (CS) gene expression and enzymatic activity in rat skeletal and cardiac muscles. Adult rats were endurance trained for 8 wk on a treadmill. They were killed 1 h (T1, n = 8) or 48 h (T48, n= 8) after their last bout of exercise training. Eight rats were sedentary controls (C) during the training period. CS mRNA levels and enzymatic activities of the soleus and ventricle muscles were determined. Training resulted in higher CS mRNA levels in both the soleus muscles (21% increase in T1; 18% increase in T48, P < 0.05) and ventricle muscles (23% increase in T1; 17% increase in T48, P < 0.05) when compared with the C group. The CS enzyme activities were 42 ( P < 0.01) and 25% ( P < 0.01) greater in the soleus muscles of T1 and T48 groups, respectively, when compared with that of the C group. Soleus CS enzyme activity was significantly greater in the T1 vs. T48 groups ( P < 0.05). However, no appreciable alterations in CS enzyme activities were observed in the ventricle muscles in both training groups. These findings suggest differential responses of skeletal and cardiac muscles in CS enzymatic activity but similar responses in CS gene expression at 1 and 48 h after the last session of endurance training. Moreover, our data support the existence of an acute effect of exercise on the training-induced elevation in CS activity in rat soleus but not ventricle muscles.

scholarly journals Differential regulation of antioxidant enzymes in Frankliniella occidentalis (Thysanoptera: Thripidae) exposed to thermal stress

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12089
Author(s):  
Jia-Wen Yuan ◽  
Yutao Zheng ◽  
Ya-Wen Chang ◽  
Jing Bai ◽  
Jing Qin ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Antioxidant Enzymes ◽  
Time Course ◽  
Frankliniella Occidentalis ◽  
Insect Pest ◽  
Expression Patterns ◽  
Global Scale ◽  
Antioxidant Genes ◽  
Agronomic Crops ◽  
Time Course Study

Frankliniella occidentalis is an invasive insect pest that incites damage to ornamental and agronomic crops on a global scale. In this study, the effects of temperature on gene expression and enzyme activity were studied for superoxide dismutase (SOD), peroxidase (POD), and glutathione-S-transferase (GST) in F. occidentalis. SOD, POD and GST enzyme activity increased significantly at 35–37 °C but declined as the temperature increased to 41 °C. In a time course study at 35 °C, SOD, POD and GST activities were significantly elevated at 0.5, 1 and 2 h in comparison to the control at 26 °C. Expression patterns were evaluated for the three antioxidant genes under high and low temperature stress. In a time course study at –4 °C, SOD, POD and GST expression peaked at 1 h and declined at 2 h of exposure. In contrast, when transcription was monitored at 35 °C, expression was lowest at 1 h and increased at 2 h. The results provide data that will be useful in deciphering the role of antioxidant enzymes in the adaptation of F. occidentalis to climate change.

scholarly journals Expression of Chlorite Dismutase and Chlorate Reductase in the Presence of Oxygen and/or Chlorate as the Terminal Electron Acceptor in Ideonella dechloratans

2012 ◽  
Vol 78 (12) ◽  
pp. 4380-4385 ◽  
Author(s):  
Miriam Hellberg Lindqvist ◽  
Nicklas Johansson ◽  
Thomas Nilsson ◽  
Maria Rova
Keyword(s):  
Enzyme Activity ◽  
Enzyme Activities ◽  
Mrna Level ◽  
Transcriptional Level ◽  
Mrna Levels ◽  
Chlorite Dismutase ◽  
Terminal Electron Acceptor ◽  
Content Type ◽  
Cell Extracts ◽  
Chlorate Reductase

ABSTRACTThe ability of microorganisms to perform dissimilatory (per)chlorate reduction is, for most species, known to be oxygen sensitive. Consequently, bioremediation processes for the removal of oxochlorates will be disturbed if oxygen is present. We measured the expression of chlorite dismutase and chlorate reductase in the presence of different terminal electron acceptors in the chlorate reducerIdeonella dechloratans. Enzyme activity assays and mRNA analyses by real-time quantitative reverse transcription (qRT)-PCR were performed on cell extracts from cells grown aerobically with and without chlorate and on cells grown anaerobically in the presence of chlorate. Our results showed that both chlorite dismutase and chlorate reductase are expressed during aerobic growth. However, transfer to anaerobic conditions with chlorate resulted in significantly enhanced enzyme activities and mRNA levels for both enzymes. Absence of oxygen was necessary for the induction to occur, since chlorate addition under aerobic conditions produced neither increased enzyme activities nor higher relative levels of mRNA. For chlorite dismutase, the observed increase in activity was on the same order of magnitude as the increase in the relative mRNA level, indicating gene regulation at the transcriptional level. However, chlorate reductase showed about 200 times higher enzyme activity in anaerobically induced cells, whereas the increase in mRNA was only about 10-fold, suggesting additional mechanisms influence the enzyme activity.

The Expression of mRNA and Enzyme Activity of Deoxycytidine- and Deoxyguanosine Kinases in Cell from Patients with Untreated B-Cell Chronic Lymphocytic Leukemia.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4378-4378
Author(s):  
Kourosh Lotfi ◽  
Karin Karlsson ◽  
Gunnar Juliusson ◽  
Curt Petersona ◽  
Staffan Eriksson ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Chronic Lymphocytic Leukemia ◽  
B Cell ◽  
Enzyme Activities ◽  
Lymphocytic Leukemia ◽  
Phase Iii ◽  
Mrna Levels ◽  
Purine Analogues ◽  
Important Place ◽  
Response To Chemotherapy

Abstract Chronic lymphocytic leukemia (CLL) is the most common leukemia in Europe and North America. The purine analogues fludarabine and cladribine have earned an important place in the treatment of CLL. Yet, the alkylating agent chlorambucil still remains as cornerstone of treatment. A gradual shift towards the use of purine analogues as the central component has become apparent however it is of greatest importance to strictly compare the efficacy of fludarabine and cladribine to have a basis for future clinical studies with these agents. In this study 59 patients included in the international Phase III Trial for untreated B-cell CLL, were randomized in order to evaluate the efficacy of chlorambucil, fludarabine, and cladribine, as primary treatment of patients with symptomatic B-cell CLL. Both fludarabine and cladribine are prodrugs and must be phosphorylated intracellularly to monophosphates by the nuclear/cytosol enzyme deoxycytidine kinase (dCK) and possibly by the mitochondrial enzyme deoxyguanosine kinase (dGK). DCK plays a pivotal roll in the activation of fludarabine and cladribine and it has previously been reported that resistance to these drugs is mainly due to deficiency of the dCK. Before treatment, peripheral blood cells were isolated and the activity of dCK and dGK enzymes were analyzed in patient cells together with the dCK and dGK mRNA levels using the real-time quantitative PCR method. The dGK activity was considerably lower (6 fold) than the dCK activity. The enzyme activities in samples from CLL patients varied about 20 and 30 folds for dCK and dGK, respectively. The mRNA expression for dCK and dGK in patients showed also a large inter individual variability from 0,011 to 0,189 and 0,001 to 0,154 respectively. There was no correlation between enzyme activity and mRNA levels in the studied CLL patients. We could not found any spliced mRNA dCK variant in our materiel or any mutation, which could explain the discrepancy between dCK activity, and mRNA levels. In conclusion, the results suggest that dCK and dGK expression is regulated at the (post) translational level in leukemic cells. However, studies of the relationship between enzyme activities and/or mRNA levels with clinical response to chemotherapy are underway and will be reported.

Transcriptional Inactivation of p53, Bax, Bcl-2 and Mdm2 Correlates with Malignant Transformation of the Uterine Cervix

2005 ◽  
Vol 20 (1) ◽  
pp. 18-27 ◽  
Author(s):  
G. Soufla ◽  
S. Baritaki ◽  
S. Sifakis ◽  
A. Zafiropoulos ◽  
D.A. Spandidos
Keyword(s):  
Mrna Expression ◽  
Malignant Transformation ◽  
Uterine Cervix ◽  
Expression Patterns ◽  
Cellular Transformation ◽  
Pcr Analysis ◽  
Mrna Levels ◽  
Cervical Lesions ◽  
Transcript Levels ◽  
Mdm2 Mrna

Deregulation of the apoptotic machinery plays a major role in cell death, cellular transformation and cancer. p53, Bcl-2, Bcl-XL, Bax and Mdm2 mRNA expression patterns were evaluated in tissue samples with cervical intraepithelial neoplasia (CIN) and cervical cancer compared to those of normal cervical tissues, and correlated with the underlying cervical lesions. Transcript levels of the above genes were assessed by RT-PCR analysis in a total of 44 cervical specimens. p53, Bcl-2, Bax and Mdm2 transcript levels were significantly different in the normal, CIN and cancer specimen groups (p=0.003, p=0.009, p=0.040 and p=0.001, respectively). Specifically, p53, Bax and Bcl-2 exhibited substantially lower transcript levels in CIN lesions compared to controls, whereas Bax mRNA levels showed a significant decrease in cancer compared to normal specimens. Mdm2 mRNA expression was considerably lower in cancer than in CIN lesions or normal cervix. High-grade squamous intraepithelial lesions exhibited lower p53 and Bcl-2 mRNA levels than controls (p=0.002, p=0.016). Coexpression analysis revealed more correlations between the above apoptosis-related molecules in normal tissues compared to CIN or cancer specimens. p53 showed significant coexpression with Bax, Bcl-2 and Mdm2 (p=0.040, p=0.013 and p=0.015, respectively) in normal cervical specimens. Bax and Bcl-XL mRNA expression was negatively correlated. Mdm2 transcriptional levels correlated significantly with those of Bax, Bcl-XL and Bcl-2. Our findings show that p53, Bax, Bcl-2 and Mdm2 mRNA expression levels correlate with the malignant transformation of the uterine cervix. mRNA coexpression patterns of the members of the pro- and anti-apoptotic family examined in cervical carcinogenesis were found to be disrupted in CIN and cancer, as already demonstrated at the protein level.

scholarly journals Time Course of Starch Biosynthesis Enzymes Activity and Root Tuber Starch of Four Cassava Cultivars

2017 ◽  
Vol 5 (1) ◽  
pp. 103
Author(s):  
Huifang Huang ◽  
Yanchun Luo ◽  
Qiang Huang ◽  
Yinong Tian ◽  
Huimin Li ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Enzyme Activities ◽  
Time Course ◽  
Starch Content ◽  
Growth Period ◽  
Sucrose Phosphate Synthase ◽  
Soluble Starch ◽  
Root Tuber ◽  
Related Enzyme ◽  
Total Starch

To understand the accumulation rule of cassava root tuber starch, the amylose, amylopectin and total starch content of fresh root tuber, the enzyme activities of sucrose synthase (SuS, EC 2.4.1.13) and sucrose phosphate synthase (SPS, EC 2.4.1.14) of leaves, the enzyme activities of ADP-glucose pyrophosphorylase (AGPase, EC 2.7.7.27), soluble starch synthase (SSS, EC 2.4.1.21) and starch branching enzyme (SBE, EC. 2.4.1.18) of tubers were assessed by using cultivars SC201, SC205, GR891 and GR911 leaves and root tubers during their growth period, respectively. The results as follows: the enzyme activity of leaf SPS and the synthesis direction of SuS showed the highest at August, 2010, however the enzyme activity of the decomposing direction of SuS formed parabolic curve; the enzyme activity of tuber AGPase showed an increased then decreased single peak curve, the enzyme activity of tuber SSS oscillating decreased, while the enzyme activity of SBE was relatively stable; the amylose, amylopectin and total starch contents of fresh cassava tuber were all gradually increased along with the growth period. This research would enrich our knowledge of the time course of amylose, amylopectin and total starch contents of fresh cassava tuber, and above related enzyme activities.

Antioxidant enzyme activities and gene expression patterns in peanut nodules during a drought and rehydration cycle

2014 ◽  
Vol 41 (7) ◽  
pp. 704 ◽  
Author(s):  
Ana Laura Furlan ◽  
Eliana Bianucci ◽  
María del Carmen Tordable ◽  
Stella Castro ◽  
Karl-Josef Dietz
Keyword(s):  
Gene Expression ◽  
Enzyme Activity ◽  
Drought Stress ◽  
Nitrogenase Activity ◽  
Expression Patterns ◽  
Antioxidant Enzyme Activities ◽  
Symbiotic Association ◽  
Dynamic Regulation ◽  
Transcript Levels ◽  
Bradyrhizobium Sp

Drought stress is one of the most important environmental factors that affect plant growth and limit biomass production. Most studies focus on drought stress development but the reversibility of the effects receives less attention. Therefore, the present work aims to explore the biological nitrogen fixation (BNF) of the symbiotic association between peanut (Arachis hypogaea L.) and Bradyrhizobium sp. during a drought–recovery cycle with a focus on the response of enzyme activity and gene expression of the antioxidant system. Peanuts exposed to drought stress had impaired BNF, as indicated by lower nitrogenase activity, and decreased leghaemoglobin content; the latter was reversed to control values upon rehydration. Previous results demonstrated that reactive oxygen species (O2·− and H2O2) were accumulated as a consequence of drought stress, suggesting that nodules experience oxidative stress. In addition, marker transcripts responsive to drought, abscisic acid and H2O2 were upregulated. Increased transcript levels of glutathione reductase were associated with an increased enzyme activity but superoxide dismutase and glutathione S-transferase activities were unchanged, despite upregulated gene transcription. In contrast, increased activity of ascorbate peroxidase (APX) was unrelated with changes in cytosolic APX transcript levels suggesting isogene specificity. In conclusion, the work exemplarily demonstrates the efficient and dynamic regulation of antioxidant enzymes and marker compounds during drought cycling, which is likely to be a prerequisite for functional optimisation of nodule metabolism.

Human glyceraldehyde-3-phosphate dehydrogenase: mRNA levels and enzyme activity in developing muscle

1985 ◽  
Vol 5 (8) ◽  
pp. 2147-2149
Author(s):  
Y H Edwards ◽  
J C Lloyd ◽  
S L McMillan ◽  
F J Benham
Keyword(s):  
Skeletal Muscle ◽  
Enzyme Activity ◽  
Cardiac Muscle ◽  
Enzyme Activities ◽  
Mrna Levels ◽  
Adult Tissue ◽  
Adult Skeletal Muscle ◽  
Polyadenylated Rna ◽  
Dehydrogenase Enzyme ◽  
Developing Muscle

Analysis of human glyceraldehyde-3-phosphate dehydrogenase mRNA revealed that levels in adult skeletal muscle are 12-fold greater per microgram of polyadenylated RNA than in fetal skeletal muscle, whereas in cardiac muscle RNA levels were about equal in fetal and adult tissue. The mRNA levels correlate well with glyceraldehyde 3-phosphate dehydrogenase enzyme activities. There was no evidence for fetus- or tissue-specific forms.

Mitochondrial adaptations in denervated muscle: relationship to muscle performance

1991 ◽  
Vol 260 (4) ◽  
pp. C841-C850 ◽  
Author(s):  
K. L. Wicks ◽  
D. A. Hood
Keyword(s):  
Enzyme Activity ◽  
Cytochrome C ◽  
Citrate Synthase ◽  
Mitochondrial Gene ◽  
Endurance Performance ◽  
Muscle Performance ◽  
Mrna Levels ◽  
Time To Peak ◽  
Chronic Denervation ◽  
Mitochondrial Adaptations

We have studied mitochondrial adaptations in muscle subject to chronic denervation, and their relationship to muscle performance, using a model of unilateral sciatic nerve denervation in rats over periods of 2, 5, 8, 14, 21, 28, 35, and 42 days (n = 5-9 rats/day). Time to peak tension (TPT), one-half relaxation time (1/2RT), and endurance performance were evaluated during in situ stimulation of denervated and contralateral gastrocnemius-plantaris muscles. Denervation led to a 70% decline in muscle mass after 42 days. TPT and 1/2RT increased 17 and 30%, respectively, indicating a transformation toward slower muscle. The activities of the enzymes cytochrome-c oxidase (CYTOX), succinate dehydrogenase, and citrate synthase were decreased by 8-14 days, and by 42 days these were 34-58% of control. The mitochondrial phospholipid cardiolipin was reduced earlier, by 5 days, and gradually decreased to 37% of control. Thus phospholipid removal appears to precede the loss of enzyme activity during decreases in mitochondrial content. Endurance performance was reduced in parallel with decreases in enzyme activity and cardiolipin. Cytochrome c mRNA levels decreased to 52% of control by 5 days. Denervation resulted in coordinated changes in mRNA levels encoding the nuclear-derived CYTOX subunit VIc and the mitochondrially derived CYTOX subunit III. However, changes in CYTOX activity did not always parallel alterations in subunit mRNA levels. Thus transcriptional and translational mechanisms operate in regulating mitochondrial gene expression during denervation.

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