Depressed metabolism and low protein catabolism in fasting grey seal pups

1. Metabolic alterations related to protein catabolism were studied in rats in transitional states induced by changing from a low-protein (LP) (50 g casein/kg) diet to a high-protein (HP) (250 g casein/kg) diet.2. Twenty-four hours after the diet was changed, the rats showed a more rapid increase in live-weight gain than controls that had been fed on the HP diet throughout. On the 5th day after the diet change, their increase in body-weight had returned almost to the control rate. Food and therefore nitrogen intakes on the 1st and 5th days after the change in diet were the same as those of the controls. It seems likely therefore that the initial high rate of live-weight gain is an indication of a metabolic adaptation which occurred on the LP diet and which did not fully return to normal until the 5th day after the change of diet.3. N balance was higher 24 h after the change in diet than in the controls, owing to a reduction in total urinary N and in urea excretion, but when measured on the 5th day it was similar in both groups.4. Carcass N determination showed that, after 7 d on the LP diet total-, trichloroacetic acid (TCA)-soluble- and TCA-insoluble-N contents (in terms of mg/g rat) were all slightly lower than control values but they had almost returned to normal 5 d after the diet change. There was a significant increase in the TCA-soluble-N content after 24 h on the HP diet to a value greater than the control value.5. Proteolysis was measured in vitro by incubation of liver slices and diaphragms under anaerobic conditions. With liver slices it was significantly lower 24 h after the diet change than in control rats. On the 5th day it was significantly higher than 24 h after the diet change but had not quite reached the control level. In the diaphragm, proteolysis was also lower 1 d after the diet change, and had not increased at all by the 5th day.6. Ureogenesis in the liver was reduced significantly 24 h after the diet change and it had almost returned to the control level on the 5th day. On the other hand, arginase (L-arginine amidinohydrolase; EC 3·5·3·1) activity was significantly lower 24 h after the diet change and did return completely to the control level on the 5th day.7. These results show that the initial increased N balance and reduced N excretion were due to enzymic adaptation to the LP diet, the reduced N excretion being attributable to reduction in hepatic urea production.

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Hepatic Ultrastructure Changes Induced by Lithocholic Acid

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060829 ◽

1967 ◽

Vol 25 ◽

pp. 162-163 ◽

Cited By ~ 1

Author(s):

F. G. Zaki

Keyword(s):

Endoplasmic Reticulum ◽

Lithocholic Acid ◽

Smooth Endoplasmic Reticulum ◽

Protein Diet ◽

Low Protein Diet ◽

Electron Microscopic ◽

Hydropic Degeneration ◽

Hepatic Cells ◽

Low Protein ◽

Microscopic Studies

Addition of lithocholic acid (LCA), a naturally occurring bile acid in mammals, to a low protein diet fed to rats induced marked inflammatory reaction in the hepatic cells followed by hydropic degeneration and ductular cell proliferation. These changes were accompanied by dilatation and hyperplasia of the common bile duct and formation of “gallstones”. All these changes were reversible when LCA was withdrawn from the low protein diet except for the hardened gallstones which persisted.Electron microscopic studies revealed marked alterations in the hepatic cells. Early changes included disorganization, fragmentation of the rough endoplasmic reticulum and detachment of its ribosomes. Free ribosomes, either singly or arranged in small clusters were frequently seen in most of the hepatic cells. Vesiculation of the smooth endoplasmic reticulum was often encountered as early as one week after the administration of LCA (Fig. 1).

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Mitochondrial Changes in Choline-Deficient Rat Myocardium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100305 ◽

1968 ◽

Vol 26 ◽

pp. 112-113

Author(s):

F. G. Zaki

Keyword(s):

Muscle Fibers ◽

Liver Mitochondria ◽

Ultrastructural Changes ◽

Choline Deficiency ◽

Nutritional Disorder ◽

Low Protein ◽

Structural Abnormalities ◽

Cross Striation ◽

Pericardial Edema ◽

Myocardial Lesions

Choline-deficiency was induced in Holtzman young rats of both sexes by feeding them a high fat - low protein diet.Preliminary studies of the ultrastructural changes in the myocardium of these animals have been recently reported from this laboratory. Myocardial lesions first appeared in the form of intraventricular mural thrombi, loss of cross striation of muscle fibers and focal necrosis of muscle cells associated with interstitial myocarditis. Prolonged choline-deficiency induced cardiomegaly associated with pericardial edema.During the early phase of this nutritional disorder, heart mitochondria - despite of not showing any swelling similar to that usually encountered in liver mitochondria of the same animal - ware the most ubiquitous site of marked structural abnormalities. Early changes in mitochondria appeared as vacuolation, disorganization, disruption and loss of cristae. Degenerating mitochondria were often seen quite enlarged and their matrix was replaced by whorls of myelin figures resembling lysosomal structures especially where muscle fibers were undergoing necrosis. In some areas, mitochondria appeared to be unusually clumped together where some contained membranelined vacuoles and others enclosed dense bodies and granular inclusions.

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Ernährung bei chronisch Nierenkranken – Wie kann man eine Low-Protein-Diet erreichen?

Dialyse aktuell ◽

10.1055/s-0035-1555716 ◽

2015 ◽

Vol 19 (05) ◽

pp. 256-256

Keyword(s):

Protein Diet ◽

Low Protein Diet ◽

Low Protein

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The Frequency of Type I Heterozygous Protein S and Protein C Deficiency in 141 Unrelated Young Patients with Venous Thrombosis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1642558 ◽

1988 ◽

Vol 59 (01) ◽

pp. 018-022 ◽

Cited By ~ 139

Author(s):

C L Gladson ◽

I Scharrer ◽

V Hach ◽

K H Beck ◽

J H Griffin

Keyword(s):

Venous Thrombosis ◽

Protein C ◽

Antithrombin Iii ◽

Young Patients ◽

Protein S ◽

Type I ◽

Protein S Deficiency ◽

Protein C Deficiency ◽

Low Protein ◽

S Deficiency

SummaryThe frequency of heterozygous protein C and protein S deficiency, detected by measuring total plasma antigen, in a group (n = 141) of young unrelated patients (<45 years old) with venous thrombotic disease was studied and compared to that of antithrombin III, fibrinogen, and plasminogen deficiencies. Among 91 patients not receiving oral anticoagulants, six had low protein S antigen levels and one had a low protein C antigen level. Among 50 patients receiving oral anticoagulant therapy, abnormally low ratios of protein S or C to other vitamin K-dependent factors were presented by one patient for protein S and five for protein C. Thus, heterozygous Type I protein S deficiency appeared in seven of 141 patients (5%) and heterozygous Type I protein C deficiency in six of 141 patients (4%). Eleven of thirteen deficient patients had recurrent venous thrombosis. In this group of 141 patients, 1% had an identifiable fibrinogen abnormality, 2% a plasminogen abnormality, and 3% an antithrombin III deficiency. Thus, among the known plasma protein deficiencies associated with venous thrombosis, protein S and protein C. deficiencies (9%) emerge as the leading identifiable associated abnormalities.

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Platelet Aggregation in Rats in Relation to Hyperuricaemia Induced by Dietary Single-Cell Protein and to Protein Deficiency

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646695 ◽

1978 ◽

Vol 39 (02) ◽

pp. 346-359 ◽

Cited By ~ 3

Author(s):

P D Winocour ◽

M R Turner ◽

T G Taylor ◽

K A Munday

Keyword(s):

Uric Acid ◽

Platelet Count ◽

Platelet Aggregation ◽

Time Lag ◽

Blood Platelet ◽

Single Cell Protein ◽

Cell Protein ◽

Low Protein ◽

Blood Platelet Count ◽

Rat Platelets

SummaryA major limitation to single-cell protein (SCP) as a human food is its high nucleic acid content, the purine moiety of which is metabolised to uric acid. Rats given a Fusarium mould as a source of SCP in diets containing oxonate, a uricase inhibitor, showed elevated plasma and kidney uric acid concentrations after 21 d, which were related to the level of dietary mould. ADP-induced and thrombin-induced platelet aggregation was greater in the hyperuricaemic rats than in controls and a progressive increase in aggregation with increasing levels of dietary mould was observed. Furthermore a time-lag, exceeding the life-span of rat platelets, was observed between the development of hyperuricaemia and the increase in aggregation. A similar time-lag was observed between the lowering of the hyperuricaemia and the reduction of platelet aggregation when oxonate was removed from the diet.If human platelets react to uric acid in the same manner as rat platelets this might explain the link that has been suggested between hyperuricaemia and ischaemic heart disease. In that event diets high in nucleic acids might be contra-indicated in people at risk from ischaemic heart disease.In rats given a low protein diet (50 g casein/kg) for 21 d ADP-induced and thrombin-induced platelet aggregation and whole blood platelet count were reduced compared with control animals receiving 200 g casein/kg diet but not in rats given 90 or 130 g casein/kg diet. A study of the time course on this effect indicated that the reduction both in aggregation tendency and in whole blood platelet count occurred after 4 d of feeding the low protein diet. These values were further reduced with time.

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Does Low Protein Concentration of Tissue-type Plasminogen Activator Predict a Low Risk of Spontaneous Deep Vein Thrombosis?

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649803 ◽

1995 ◽

Vol 74 (02) ◽

pp. 718-721 ◽

Cited By ~ 8

Author(s):

Jørgen Gram ◽

Johannes Sidelmann ◽

Jørgen Jespersen

Keyword(s):

Deep Vein Thrombosis ◽

Confidence Interval ◽

Plasminogen Activator ◽

Fibrinolytic Activity ◽

Protein Concentration ◽

Tissue Type ◽

Vein Thrombosis ◽

Low Protein ◽

Deep Vein ◽

Pai 1

SummaryMany reports have demonstrated an abnormal fibrinolysis in a subset of patients with deep vein thrombosis. We have studied systemic global fibrinolytic activity and protein concentrations of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) in plasma of 25 young patients with a previous instance of spontaneous deep vein thrombosis documented by phlebography and in 50 healthy controls. The two populations were comparable with respect to a number of base-line variables (age, height, weight, etc.), while the patients had significantly lower fibrinolytic activity (p <0.02), and significantly higher protein concentrations of t-PA (p <0.0001) and PAI-1 (p <0.0006).We used probit scale plots to identify the consequence of different cut-off points to separate patients from controls. Reasonable separation could be obtained for t-PA with a cut-off point of 5.2 ng/ml and for PAI-1 18 ng/ml. The sensitivity and specificity for these cut-off points were for t-PA 73% (95% confidence interval 63%-84%) and for PAI-1 67% (confidence interval 55%-77%). The negative predictive value with a cut-off point t-PA concentration of 5.2 ng/ml was 85% (95% confidence interval 70%-94%). We observed a significantly negative association between concentration of t-PA and fibrinolytic activity (rs = -0.47; p <0.005) and also between PAI-1 and fibrinolytic activity (rs = -0.78; p <0.005).We conclude that a young healthy population is characterized by low protein concentration of t-PA (and PAI-1) compared with young patients with a previous instance of spontaneous vein thrombosis, and we tentatively state that a low protein concentration of t-PA predicts a low risk of spontaneous deep vein thrombosis.

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Utilizing next-generation sequencing to identify prey DNA in western North Atlantic grey seal Halichoerus grypus diet

Marine Ecology Progress Series ◽

10.3354/meps13520 ◽

2020 ◽

Vol 655 ◽

pp. 227-240

Author(s):

KR Flanders ◽

ZH Olson ◽

KA Ono

Keyword(s):

Next Generation Sequencing ◽

Feeding Habits ◽

Atlantic Menhaden ◽

Halichoerus Grypus ◽

Frequency Of Occurrence ◽

Grey Seal ◽

Next Generation ◽

Significant Difference ◽

Generation Sequencing ◽

Seal Diet

Increasing grey seal Halichoerus grypus abundance in coastal New England is leading to social, political, economic, and ecological controversies. Central to these issues is the foraging ecology and diet composition of the seals. We studied grey seal feeding habits through next-generation sequencing of prey DNA using 16S amplicons from seal scat (n = 74) collected from a breeding colony on Monomoy Island in Massachusetts, USA, and report frequency of occurrence and relative read abundance. We also assigned seal sex to scat samples using a revised PCR assay. In contrast to current understanding of grey seal diet from hard parts and fatty acid analysis, we found no significant difference between male and female diet measured by alpha and beta diversity. Overall, we detected 24 prey groups, 18 of which resolved to species. Sand lance Ammodytes spp. were the most frequently consumed prey group, with a frequency of occurrence (FO) of 97.3%, consistent with previous studies, but Atlantic menhaden Brevoortia tyrannus, the second most frequently consumed species (FO = 60.8%), has not previously been documented in US grey seal diet. Our results suggest that a metabarcoding approach to seal food habits can yield important new ecological insights, but that traditional hard parts analysis does not underestimate consumption of Atlantic cod Gadus morhua (FO = 6.7%, Gadidae spp.) and salmon Salmo salar (FO = 0%), 2 particularly valuable species of concern.

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