In vitro fibre fermentation of feed ingredients with varying fermentable carbohydrate and protein levels and protein synthesis by colonic bacteria isolated from pigs

1. Eighteen pigs were offered diets containing 130, 170 or 210 g protein/kg with three barrows and three gilts per diet from 20 to 60 kg live weight. Oxygen consumption, Na1, K1-ATPase (EC 3·6·1· 3)-dependent and -independent respiration and protein synthesis were measured in vitro in intercostal and sartorius muscle preparations from these pigs.2. Increasing dietary protein concentration increased (P < 0·01) daily gain and dissectible muscle in carcass.3. O2 consumption and Na+, K+-ATPase-dependent respiration of the intercostal and sartorius muscles increased linearly (P < 0·01) with increase in dietary protein concentration. The requirement for the support of the transport of Na+ and K+ across the cell membrane in these muscles, on average, accounted for 22–25% of the O2 consumption.4. Synthesis rate (mg/g per d) of protein in the sartorius muscle increased (P < 0·05) from 3·05 to 5·07 and increased (P < 0·1) from 2·57 to 4.06 in the intercostal muscle as dietary protein increased from 130 to 210 g/kg diet.5. Regression of Na+, K+-ATPase-dependent respiration against protein synthesis in each of intercostal and sartorius muscles showed a linear relation, an attestation of a close link between productive processes and auxiliary energy expenditure.

Download Full-text

The source of fermentable carbohydrates influences the in vitro protein synthesis by colonic bacteria isolated from pigs

animal ◽

10.1017/s1751731107000584 ◽

2007 ◽

Vol 1 (8) ◽

pp. 1126-1133 ◽

Cited By ~ 17

Author(s):

J. Bindelle ◽

A. Buldgen ◽

J. Wavreille ◽

R. Agneessens ◽

J.P. Destain ◽

...

Keyword(s):

Protein Synthesis ◽

In Vitro Protein Synthesis ◽

Colonic Bacteria ◽

Fermentable Carbohydrates ◽

Vitro Protein

Download Full-text

MAP2 is differentially phosphorylated in schizophrenia, altering its function

Molecular Psychiatry ◽

10.1038/s41380-021-01034-z ◽

2021 ◽

Author(s):

M. J. Grubisha ◽

X. Sun ◽

M. L. MacDonald ◽

M. Garver ◽

Z. Sun ◽

...

Keyword(s):

Protein Synthesis ◽

Disease Risk ◽

Protein Translation ◽

Synaptic Proteins ◽

Synaptic Protein ◽

Spine Density ◽

Neuronal Structure ◽

Protein Levels ◽

And Function

AbstractSchizophrenia (Sz) is a highly polygenic disorder, with common, rare, and structural variants each contributing only a small fraction of overall disease risk. Thus, there is a need to identify downstream points of convergence that can be targeted with therapeutics. Reduction of microtubule-associated protein 2 (MAP2) immunoreactivity (MAP2-IR) is present in individuals with Sz, despite no change in MAP2 protein levels. MAP2 is phosphorylated downstream of multiple receptors and kinases identified as Sz risk genes, altering its immunoreactivity and function. Using an unbiased phosphoproteomics approach, we quantified 18 MAP2 phosphopeptides, 9 of which were significantly altered in Sz subjects. Network analysis grouped MAP2 phosphopeptides into three modules, each with a distinct relationship to dendritic spine loss, synaptic protein levels, and clinical function in Sz subjects. We then investigated the most hyperphosphorylated site in Sz, phosphoserine1782 (pS1782). Computational modeling predicted phosphorylation of S1782 reduces binding of MAP2 to microtubules, which was confirmed experimentally. We generated a transgenic mouse containing a phosphomimetic mutation at S1782 (S1782E) and found reductions in basilar dendritic length and complexity along with reduced spine density. Because only a limited number of MAP2 interacting proteins have been previously identified, we combined co-immunoprecipitation with mass spectrometry to characterize the MAP2 interactome in mouse brain. The MAP2 interactome was enriched for proteins involved in protein translation. These associations were shown to be functional as overexpression of wild type and phosphomimetic MAP2 reduced protein synthesis in vitro. Finally, we found that Sz subjects with low MAP2-IR had reductions in the levels of synaptic proteins relative to nonpsychiatric control (NPC) subjects and to Sz subjects with normal and MAP2-IR, and this same pattern was recapitulated in S1782E mice. These findings suggest a new conceptual framework for Sz—that a large proportion of individuals have a “MAP2opathy”—in which MAP function is altered by phosphorylation, leading to impairments of neuronal structure, synaptic protein synthesis, and function.

Download Full-text

MAP2 is Differentially Phosphorylated in Schizophrenia, Altering its Function

10.1101/683912 ◽

2019 ◽

Author(s):

MJ Grubisha ◽

X Sun ◽

ML MacDonald ◽

M Garver ◽

Z Sun ◽

...

Keyword(s):

Protein Synthesis ◽

Disease Risk ◽

Protein Translation ◽

Synaptic Proteins ◽

Synaptic Protein ◽

Spine Density ◽

Neuronal Structure ◽

Protein Levels ◽

And Function

AbstractSchizophrenia (Sz) is a highly polygenic disorder, with common, rare, and structural variants each contributing only a small fraction of overall disease risk. Thus, there is a need to identify downstream points of convergence that can be targeted with therapeutics. Reduction of Microtubule-associated Protein 2 (MAP2) immunoreactivity (MAP2-IR) is present in individuals with Sz, despite no change in MAP2 protein levels. MAP2 is phosphorylated downstream of multiple receptors and kinases identified as Sz risk genes, altering its immunoreactivity and function. Using an unbiased phosphoproteomics approach we quantified 18 MAP2 phosphopeptides, 9 of which were significantly altered in Sz subjects. Network analysis grouped MAP2 phosphopeptides into 3 modules, each with a distinct relationship to dendritic spine loss, synaptic protein levels, and clinical function in Sz subjects. We then investigated the most hyperphosphorylated site in Sz, phosphoserine1782 (pS1782). Computational modeling predicted phosphorylation of S1782 reduces binding of MAP2 to microtubules, which was confirmed experimentally. We generated a transgenic mouse containing a phosphomimetic mutation at S1782 (S1782E) and found reductions in basilar dendritic length and complexity along with reduced spine density. Because only a limited number of MAP2 interacting proteins have been previously identified, we combined co-immunoprecipitation with mass spectrometry to characterize the MAP2 interactome in mouse brain. The MAP2 interactome was enriched for proteins involved in protein translation. These associations were shown to be functional as overexpression of wildtype and phosphomimetic MAP2 reduced protein synthesis in vitro. Finally, we found that Sz subjects with low MAP2-IR had reductions in the levels of synaptic proteins relative to nonpsychiatric control (NPC) subjects and to Sz subjects with normal and MAP2-IR, and this same pattern was recapitulated in S1782E mice. These findings suggest a new conceptual framework for Sz - that a large proportion of individuals have a “MAP2opathy” - in which MAP function is altered by phosphorylation, leading to impairments of neuronal structure, synaptic protein synthesis, and function.

Download Full-text

Deriving accurate molecular indicators of protein synthesis through Raman-based sparse classification

10.1101/2021.03.02.433529 ◽

2021 ◽

Author(s):

N. Pavillon ◽

N. I. Smith

Keyword(s):

Protein Synthesis ◽

Linear Models ◽

Linear Method ◽

Classification Performance ◽

Experimental Conditions ◽

Protein Levels ◽

Spectral Coefficients ◽

Rna Accumulation ◽

Molecular Indicators

AbstractRaman spectroscopy has the ability to retrieve molecular information from live biological samples non-invasively through optical means. Coupled with machine learning, it is possible to use the large amount of information contained in a Raman spectrum to create models that can predict the state of new samples based on statistical analysis from previous measurements. Furthermore, in case of linear models, the separation coefficients can be used to interpret which bands are contributing to the discrimination between experimental conditions, which correspond here to single-cell measurements of macrophages under in vitro immune stimulation. We here evaluate a typical linear method using discriminant analysis and PCA, and compare it to regularized logistic regression (Lasso). We find that the use of PCA is not beneficial to the classification performance. Furthermore, the Lasso approach yields sparse separation vectors, since it suppresses spectral coefficients which do not improve classification, making interpretation easier. To further evaluate the approach, we apply the Lasso technique to a well-defined case where protein synthesis is inhibited, and show that the separating features are consistent with RNA accumulation and protein levels depletion. Surprisingly, when Raman features are selected purely in terms of their classification power (Lasso), the selected coefficients are contained in side bands, while typical strong Raman peaks are not present in the discrimination vector. We propose that this occurs because large Raman bands are representative of a wide variety of cellular molecules and are therefore less suited for accurate classification.

Download Full-text

Increased Protein Synthesis by Human Platelets during Phagocytosis of Latex Particles in Vitro

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647928 ◽

1976 ◽

Vol 35 (02) ◽

pp. 350-357 ◽

Cited By ~ 8

Author(s):

Hana Bessler ◽

Galila Agam ◽

Meir Djaldetti

Keyword(s):

Protein Synthesis ◽

Fold Increase ◽

Human Platelets ◽

Polystyrene Latex ◽

Latex Particles ◽

The Third ◽

Platelet Protein ◽

Dose Dependent ◽

Phagocytotic Activity

SummaryA three-fold increase of protein synthesis by human platelets during in vitro phagocytosis of polystyrene latex particles was detected. During the first two hours of incubation, the percentage of phagocytizing platelets and the number of latex particles per platelet increased; by the end of the third hour, the first parameter remained stable, while the number of latex particles per cell had decreased.Vincristine (20 μg/ml of cell suspension) inhibited platelet protein synthesis. This effect was both time- and dose-dependent. The drug also caused a decrease in the number of phagocytizing cells, as well as in their phagocytotic activity.

Download Full-text

EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

Acta Endocrinologica ◽

10.1530/acta.0.0770064 ◽

1974 ◽

Vol 77 (1) ◽

pp. 64-70 ◽

Cited By ~ 9

Author(s):

Gustav Wägar

Keyword(s):

Protein Synthesis ◽

Actinomycin D ◽

The Other ◽

Leucine Incorporation ◽

Short Term ◽

Other Hand ◽

Thyroid Glands ◽

Translational Level ◽

Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

Download Full-text

INHIBITION OF THYROGLOBULIN BIOSYNTHESIS AND DEGRADATION BY EXCESS IODIDE. SYNERGISM WITH LITHIUM

Acta Endocrinologica ◽

10.1530/acta.0.0810495 ◽

1976 ◽

Vol 81 (2) ◽

pp. 495-506 ◽

Cited By ~ 9

Author(s):

A. Radvila ◽

R. Roost ◽

H. Bürgi ◽

H. Kohler ◽

H. Studer

Keyword(s):

Protein Synthesis ◽

Thyroid Gland ◽

Inhibitory Action ◽

Inhibit Protein Synthesis ◽

Thyrotrophic Hormone ◽

Thyroid Glands ◽

Pre Treatment ◽

Excess Iodide ◽

Kidney Liver

ABSTRACT Lithium and excess iodide inhibit the release of thyroid hormone from preformed stores. We thus tested the hypothesis that this was due to an inhibition of thyroglobulin breakdown. Rats were pre-treated with propylthiouracil (PTU) for 3 weeks in order to deplete their thyroids of thyroglobulin. While the PTU was continued, lithium chloride (0.25 mEq./100 g weight) or potassium iodide (3 mg per rat) were injected every 12 h for 3 days. Thereafter the thyroglobulin content in thyroid gland homogenates was measured. PTU pre-treatment lowered the thyroglobulin content from 4.21 to 0.22 mg/100 mg gland. Lithium caused a marked re-accumulation of thyroglobulin to 0.60 mg/100 mg within 3 days. While iodide alone had only a borderline effect, it markedly potentiated the action of lithium and a combination of the two drugs increased the thyroglobulin content to 1.04 mg/100 mg. Thyroxine was injected into similarly pre-treated animals to suppress secretion of thyrotrophic hormone. This markedly inhibited the proteolysis of thyroglobulin and 1.3 mg/100 mg gland accumulated after 3 days. Excess iodide, given in addition to thyroxine, decreased the amount of thyroglobulin accumulated to 0.75 mg/100 mg gland. To study whether this could be explained by an inhibitory action of iodide on thyroglobulin biosynthesis, thyroid glands from animals treated with excess iodide were incubated in vitro in the presence of 0.2 mm iodide for 3 h. Iodide decreased the incorporation of radioactive leucine into total thyroidal protein and into thyroglobulin by 25 and 35 % respectively. Iodide did not inhibit protein synthesis in the kidney, liver or muscle tissue. Thus, large doses of iodide selectively inhibit thyroglobulin biosynthesis.

Download Full-text

AAnti-Inflammatory Effects of Plasma Circulating Exosomes Obtained from Normal-Weight and Obese Subjects on Hepatocytes

Endocrine Metabolic & Immune Disorders - Drug Targets ◽

10.2174/1871530320666200505121426 ◽

2020 ◽

Vol 20 ◽

Author(s):

Reza Afrisham ◽

Sahar Sadegh-Nejadi ◽

Reza Meshkani ◽

Solaleh Emamgholipour ◽

Molood Bagherieh ◽

...

Keyword(s):

Inflammatory Cytokines ◽

Hepg2 Cells ◽

Human Liver ◽

Liver Cells ◽

Normal Weight ◽

Protein Levels ◽

Human Liver Cells ◽

Tnf Α ◽

Anti Inflammatory

Introduction: Obesity is a disorder with low-grade chronic inflammation that plays a key role in the hepatic inflammation and steatosis. Moreover, there are studies to support the role of exosomes in the cellular communications, the regulation of metabolic homeostasis and immunomodulatory activity. Accordingly, we aimed to evaluate the influence of plasma circulating exosomes derived from females with normal-weight and obesity on the secretion of inflammatory cytokines in human liver cells. Methods: Plasma circulating exosomes were isolated from four normal (N-Exo) and four obese (O-Exo) women. The exosomes were characterized and approved for CD63 expression (common exosomal protein marker) and morphology/size using the western blot and TEM methods, respectively. The exosomes were used for stimulation of HepG2 cells in vitro. After 24 h incubation, the protein levels of TNF-α,IL-6, and IL-1β were measured in the culture supernatant of HepG2 cells using the ELISA kit. Results: The protein levels of IL-6 and TNF-α in the cells treated with O-Exo and N-Exo reduced significantly in comparison with control group (P=0.039 and P<0.001 respectively), while significance differences were not found between normal and obese groups (P=0.808, and P=0.978 respectively). However, no significant differences were found between three groups in term of IL-1β levels (P=0.069). Based on the correlation analysis, the protein levels of IL-6 were positively correlated with TNF-α (r 0.978, P<0.001). Conclusion: These findings suggest that plasma circulating exosomes have probably anti-inflammatory properties independently from body mass index and may decrease the secretion of inflammatory cytokines in liver. However, further investigations in vitro and in vivo are needed to address the anti-inflammatory function of N-Exo and O-Exo in human liver cells and/or other cells.

Download Full-text