scholarly journals STUDIES ON THE BIOCHEMISTRY OF MITOCHONDRIA AND CELL MORPHOLOGY IN THE NEONATAL SWINE HEPATOCYTE

1972 ◽  
Vol 53 (2) ◽  
pp. 335-347 ◽  
Author(s):  
H. J. Mersmann ◽  
J. Goodman ◽  
J. M. Houk ◽  
S. Anderson

Mitochondrial preparations isolated from neonatal swine hepatocytes show a marked increase in oxidative and concomitant phosphorylative capacity between birth and 2 days postpartum. There are no changes in the coupling parameters (respiratory control ratio and adenosine diphosphate/O ratio) with age. Changes in sedimentation properties in a sucrose gradient suggest qualitative changes in the mitochondria. Some of the lipid measurements (increased phospholipid) might be interpreted as supportive of this suggestion, although most could also be regarded as indicative of quantitative changes (increased number of mitochondria). Electron microscopy of isolated mitochondria and of the hepatocyte demonstrated an increased number of mitochondria but no change in shape, size, or structure as the pig developed. An increase in a number of cytoplasmic components (Golgi apparatus and endoplasmic reticulum) and a decrease in glycogen were also observed. The functional changes in mitochondria seem to occur within a short period of time (6–12 hr postpartum).

1969 ◽  
Vol 15 (8) ◽  
pp. 975-977 ◽  
Author(s):  
K. Watson ◽  
W. Paton ◽  
J. E. Smith

Mitochondria isolated from Aspergillus oryzae exhibited respiratory control with a range of substrates. Bovine serum albumin was required in the reaction medium to observe adenosine diphosphate (ADP) controlled respiration. The mitochondria carried out active oxidation and phosphorylation with citrate as substrate in the pH range 6–7 and showed a slight optimum for oxidative phosphorylation at pH 6.5. The respiratory properties of the isolated mitochondria were similar to those reported for A. niger and yeast mitochondria.


1924 ◽  
Vol 6 (6) ◽  
pp. 629-633
Author(s):  
Samuel Brody

The curves of growth and of regeneration follow the same course, and can be represented by the same exponential equation. This is taken to substantiate the theory that growth and regeneration are essentially identical processes governed by the same laws. A common peculiarity of the curves of growth and of regeneration is that during a short period in the early stages of regeneration and of growth, the apparent observed speed of these processes seems to be relatively slow. As a result, the curve of the fitted equation cuts the time axis not at zero, the beginning of growth or regeneration, but somewhat later. Data on regeneration are cited indicating that the initial slow phase of regeneration is due to the time required for the formation of a cap of embryonic cells which serves as a basis for the more active later regeneration; in other words, to qualitative growth which cannot be expressed in terms of quantitative units. It is suggested that the apparent initial slow phase of growth of the individual from the fertilized egg is due to a similar qualitative growth. It is suggested that if the initial qualitative changes could be converted into some common unit with the subsequent quantitative changes, the apparent initial lag would disappear, and the exponential equation representing the course of these processes would then be the same as the equation used to represent the course of a monomolecular chemical reaction. Certain implications of this reasoning are discussed in the text.


1982 ◽  
Vol 3 (2) ◽  
pp. 183-194 ◽  
Author(s):  
Nicholas Dorn ◽  
Nigel South

A review of the available empirical material bearing upon the question of alcohol advertising having ‘effects’ on the general level of consumption suggests that this question is insufficiently precise as a basis for research. Studies suggesting some relationship between advertising for particular brands or products and shifts in brand or product use are potentially more interesting, if considered from a point of view that recognises that such shifts may involve shifts in milieux, comparisons, styles and meanings associated with consumption. Future research should be attentive to such qualitative changes in drinking practices attendant upon advertising or preventive campaigns (as well as to quantitative changes). The authors suggest that such quantitative and qualitative changes in drinking practices of individuals and social groups need to be considered within the context of more general, ideological and economic, consequences of alcohol advertising. These consequences-including reinforcement of images about ‘social drinking,’ and shifting of consumers onto more profitable products-consolidate the profitability of the alcohol industry (a consideration more important to the industry than levels of consumption per se). A framework broader than that of ‘effects’ on individuals' levels of consumption is required if health educators are to learn anything from advertising.


2011 ◽  
Vol 5 (2) ◽  
pp. 29-36
Author(s):  
Jan Chrudimský ◽  
Michal Šteffl

By the content of article we are bringing a view about research study results, which deal with identification achievement in men’s and women’s artistic gymnastics and at the same time brings scope of their diagnostics. The characteristic attribute of artistic gymnastics achievement is correct and formally excellent realizations of different gymnastic skills with variety of their difficulty. Qualitative changes of gymnastics achievements are followed by many morphological, structural and their results from functional changes, which is useful longitudinally monitor and evaluate. As the most frequently are possible designate tests of static and dynamic power, anaerobic and aerobic capacity and also a test of heart rate dynamic during gymnastics competitions.


2011 ◽  
pp. S177-S184 ◽  
Author(s):  
Z. KOJIC ◽  
K. GOPCEVIC ◽  
D. MARINKOVIC ◽  
G. TASIC

Angiotensin converting enzyme inhibitors are widely used in therapy of cardiovascular diseases. However, the consensus on effects of these inhibitors in control of myocardial oxygen consumption during the process of experimental hypercholesterolemia and under the condition of endothelial dysfunction has not been reached. Here we examined effects of captopril, an angiotensin converting enzyme inhibitor, on serum lipid levels and oxygen consumption rate in mitochondria isolated from heart of rabbits treated by hypercholesterolemic diet. During the twelve-week period, the Chinchilla male rabbits were daily treated by saline (controls); 1 % cholesterol diet; 5 mg/kg/day captopril or 1 % cholesterol + 5 mg/kg/day captopril. Total- and high-density lipoprotein cholesterol and triglyceride in serum were measured spectrophotometricly. The left ventricle mitochondrial fraction was isolated and myocardial oxygen consumption was measured by Biological Oxygen Monitor. Mitochondria isolated from hearts of rabbits exposed to hypercholesterolemic diet showed significantly reduced respiration rates (state 3 and state 4) with altering adenosine diphosphate/oxygen ratio, whereas the respiratory control ratio was not affected when compared to controls. Mitochondria from cholesterol/captopril–treated animals showed significantly reduced respiration rates without altering adenosine diphosphate/oxygen ratio index or respiratory control ratio. Although captopril did not exert the favorable effect on serum lipid levels in cholesterol-treated animals, it restored the mitochondrial oxygen consumption. Further studies should be performed to define the underlying physiological and/or pathophysiological mechanisms and clinical implications.


2018 ◽  
Vol 50 (6) ◽  
pp. 440-447 ◽  
Author(s):  
Louise C. Evans ◽  
Alex Dayton ◽  
Chun Yang ◽  
Pengyuan Liu ◽  
Theresa Kurth ◽  
...  

Studies exploring the development of hypertension have traditionally been unable to distinguish which of the observed changes are underlying causes from those that are a consequence of elevated blood pressure. In this study, a custom-designed servo-control system was utilized to precisely control renal perfusion pressure to the left kidney continuously during the development of hypertension in Dahl salt-sensitive rats. In this way, we maintained the left kidney at control blood pressure while the right kidney was exposed to hypertensive pressures. As each kidney was exposed to the same circulating factors, differences between them represent changes induced by pressure alone. RNA sequencing analysis identified 1,613 differently expressed genes affected by renal perfusion pressure. Three pathway analysis methods were applied, one a novel approach incorporating arterial pressure as an input variable allowing a more direct connection between the expression of genes and pressure. The statistical analysis proposed several novel pathways by which pressure affects renal physiology. We confirmed the effects of pressure on p-Jnk regulation, in which the hypertensive medullas show increased p-Jnk/Jnk ratios relative to the left (0.79 ± 0.11 vs. 0.53 ± 0.10, P < 0.01, n = 8). We also confirmed pathway predictions of mitochondrial function, in which the respiratory control ratio of hypertensive vs. control mitochondria are significantly reduced (7.9 ± 1.2 vs. 10.4 ± 1.8, P < 0.01, n = 6) and metabolomic profile, in which 14 metabolites differed significantly between hypertensive and control medullas ( P < 0.05, n = 5). These findings demonstrate that subtle differences in the transcriptome can be used to predict functional changes of the kidney as a consequence of pressure elevation.


2020 ◽  
Author(s):  
Juan C Diaz Zagoya ◽  
Alejandro Marín-Medina ◽  
Alma M. Zetina-Esqu ◽  
Jorge L. Blé-Castillo ◽  
Andrés E. Castell-Rodríguez ◽  
...  

Abstract Background: Statins are the cornerstone of therapy in patients with hyperlipidemia. In high risk patients statins are employed for aggressive therapy, however part of the users are intolerant to these drugs. The aim of this study was to analyze the undesirable effects of moderate, median and high doses of rosuvastatin in CD-1 male mice that received a cholesterol-rich diet, focusing in the morphological and functional changes on hepatocyte mitochondria. Methods: We studied in a mouse model the combined administration of a cholesterol-rich diet (HD) along with a moderate high dose of rosuvastatin (Ro): 1, 2.5 or 5 mg/Kg/day during several days. Animals (n=6) were sacrificed, the liver mitochondria were isolated for analysis of respiratory function and microscopic studies. The respiratory control (state 3/state 4) and the O2 expenditure (nanoatoms/min/mg proteins) were evaluated. Results: Rosuvastatin doses higher than 20 mg/Kg/day induced premature death in hypercholesterolemic mice but not in mice with a cholesterol-free diet. Doses from 2.5 to 5 mg/Kg/day also induced morphological and functional alterations in mitochondria but the hypercholesterolemic animals survived longer. A dose of 1 mg/Kg/day, which is close to the maximal therapeutic dose employed in humans, did not affect mitochondrial architecture or respiratory function after two months of treatment. We analyzed the effect of rosuvastatin on the hepatic tissue where statins are most retained after their administration, and the main site of endogenous cholesterol synthesis. Conclusions: Our results contribute to understand the undesirable side effects of rosuvastatin in hypercholesterolemic mice, effects that can also be present in human being intolerant to statins.


2013 ◽  
Vol 45 (5) ◽  
pp. 163-170 ◽  
Author(s):  
Martin Bienengraeber ◽  
Molly Pellitteri-Hahn ◽  
Naoyuki Hirata ◽  
Tesfaye M. Baye ◽  
Zeljko J. Bosnjak ◽  
...  

Changes in mitochondrial bioenergetics have been proposed to be critical for triggering and effecting anesthetic-induced preconditioning (APC) against cardiac ischemia and reperfusion injury. The objective of this study was to analyze changes in mitochondrial protein levels and link those changes to potential functional changes. A 18O-labeling method was applied for relative comparison of cardiac mitochondrial samples from control and isoflurane exposed rats before and after ischemia and reperfusion. Wistar rats were exposed to isoflurane for 30 min (APC) or did not receive the anesthetic (control). Rats were subjected to 30 min coronary occlusion and 15 min reperfusion without (ischemia) or after APC (ischemia + APC). The following comparisons were made: control vs. APC, control vs. ischemia, and APC vs. ischemia + APC. Proteins were analyzed by liquid chromatography-mass spectrometry. A total of 98 proteins currently annotated as mitochondrial proteins in the UniProt database were positively identified from three replicate experiments. Most of the changes during APC and ischemia occur in complexes of the electron transport chain. Overall, fewer changes in ETC complexes were found when comparing APC with APC + ischemia than when comparing control and ischemia. This corresponds to the preservation of bioenergetics due to APC after ischemia and reperfusion as indicated by preserved ATP level and generation. APC itself induced changes in complex I, but those changes were not correlated with activity changes in mitochondria after APC. Thus, a proteomic mass spectral approach does not only assess quantitative changes without prior knowledge of proteins, but also allows insight into the mechanisms of ischemia and reperfusion injury and APC.


1991 ◽  
Vol 260 (1) ◽  
pp. R159-R166 ◽  
Author(s):  
M. E. Chamberlin ◽  
H. C. Glemet ◽  
J. S. Ballantyne

Amino acid metabolism was examined in mitochondria from the lateral red muscle of a teleost (lake char, Salvelinus namaycush) and a nonteleost fish (bowfin, Amia calva). Isolated mitochondria oxidize a wide variety of substrates and have high respiratory control ratios. In both species, glutamine is oxidized more rapidly than any other amino acid. The rate of glutamine oxidation by bowfin mitochondria exceeds that of lake char mitochondria, and the bowfin displays correspondingly higher levels of mitochondrial phosphate-dependent glutaminase. It is suggested that amino acids in general, and glutamine in particular, are important oxidative substrates for nonteleost red muscle. The teleost red muscle, however, may rely on both glutamine and fatty acids as oxidative substrates. It appears that glutamate derived from glutamine is oxidized primarily via glutamate dehydrogenase, whereas exogenous glutamate is oxidized primarily via aspartate aminotransferase. Complete oxidation of glutamine may be accomplished in the absence of other substrates by conversion of glutamine-derived malate to pyruvate via malic enzyme. To assess the relative abilities of various tissues to synthesize and oxidize glutamine, the activities of glutamine synthetase and glutaminase were measured. The results of these studies indicate that the organization of glutamine metabolism of fish differs markedly from that in mammals.


Blood ◽  
1992 ◽  
Vol 79 (8) ◽  
pp. 2028-2033
Author(s):  
EI Peerschke

Progressive decreases in platelet-bound fibrinogen accessibility to antibody and enzymes were recently reported to occur after adenosine diphosphate (ADP)-induced fibrinogen binding. Because previous studies also indicated that platelets that are activated but not aggregated by ADP in the presence of fibrinogen lose their ability to aggregate in a time-dependent manner despite negligible changes in fibrinogen binding, the present study examined the relationship between platelet aggregation and accessibility of platelet-bound fibrinogen to specific polyclonal antibody F(ab')2 fragments over a 60-minute time course. Although 125I-fibrinogen binding remained virtually unchanged, comparison of antifibrinogen antibody F(ab')2 binding and platelet aggregation 5 minutes and 60 minutes after platelet stimulation with ADP or thrombin showed decreases in F(ab')2 binding of 62% +/- 13% and 73% +/- 7% (mean +/- SD, n = 5), respectively, and decreases of 65% +/- 16% and 60% +/- 10% in platelet aggregation. In contrast, platelets stimulated with A23187 or chymotrypsin retained 87% +/- 16% and 76% +/- 12% of their ability to aggregate over the same time course, and lost only 39% +/- 14% and 36% +/- 12% of their ability to bind antifibrinogen antibody F(ab')2 fragments, respectively. Pretreatment of ADP-stimulated platelets with chymotrypsin largely prevented the progressive loss of platelet aggregability and the accompanying decreased recognition of bound fibrinogen by antifibrinogen F(ab')2 fragments. Preincubation of platelets with cytochalasin D (30 micrograms/mL) also inhibited the decrease in platelet aggregation after exposure of ADP-treated platelets to fibrinogen over a 60-minute time course. This was accompanied by only a 25% +/- 18% decrease in antifibrinogen antibody F(ab')2 binding. Present data support the hypothesis that qualitative changes in platelet-bound fibrinogen correlate with loss of the ability of platelets to aggregate, and implicate both the platelet cytoskeleton and chymotrypsin-sensitive surface membrane structures in modulating qualitative changes in bound fibrinogen on the platelet surface.


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