scholarly journals Systematic elimination of parthenogenetic cells in mouse chimeras

Development ◽  
1989 ◽  
Vol 106 (1) ◽  
pp. 29-35 ◽  
Author(s):  
R. Fundele ◽  
M.L. Norris ◽  
S.C. Barton ◽  
W. Reik ◽  
M.A. Surani
Keyword(s):  
Skeletal Muscle ◽  
Selective Pressure ◽  
Subsequent Development ◽  
Developmental Potential ◽  
Embryonic Tissues ◽  
Mouse Chimeras ◽  
Liver And Pancreas ◽  
Systematic Selection ◽  
The Brain

The developmental potential of primitive ectoderm cells lacking paternal chromosomes was investigated by examining the distribution of parthenogenetic cells in chimeras. Using GPI-1 allozymes as marker, parthenogenetic cells were detected in most organs and tissues in adult chimeras. However, these cells were under severe selective pressure compared with cells from normal fertilized embryos. In the majority of chimeras, parthenogenetic cells in individual animals were observed in a limited number of tissues and organs and, even in these instances, their contribution was substantially reduced. Nevertheless, parthenogenetic cells were detected more consistently in some organs, especially the brain, heart, kidney and spleen. In contrast, there was apparently a systematic selection against parthenogenetic cells in some tissues, most notably in skeletal muscle, liver and pancreas. These results suggest that paternally derived genes are probably required not only for the development of extraembryonic structures but also for subsequent development of embryonic tissues derived from the primitive ectoderm lineage.

Developmental potential of parthenogenetic cells: role of genotype-specific modifiers

Development ◽  
1991 ◽  
Vol 113 (3) ◽  
pp. 941-946 ◽  
Author(s):  
R. Fundele ◽  
S.K. Howlett ◽  
R. Kothary ◽  
M.L. Norris ◽  
W.E. Mills ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Marked Improvement ◽  
Mouse Strains ◽  
Developmental Potential ◽  
Imprinted Gene ◽  
The Brain ◽  
Strain Background

The developmental potential of parthenogenetic cells derived from different mouse strains was investigated by examining their distribution in various tissues of adult aggregation chimeras. Using GPI-1 allozymes as marker, no striking differences were observed between chimeras whose parthenogenetic cells were derived from activated oocytes isolated from females of different genetic backgrounds, (C57BL/6 × CBA/J) F1, CFLP, 129, and SWR. In all the combinations tested, parthenogenetic cells were consistently absent from skeletal muscle, but there were varying contributions to most other tissues. These results suggest that the maternal duplication of chromosomes containing imprinted gene(s) responsible for the systematic elimination of parthenogenetic cells from skeletal muscle, are not subject to a pronounced influence of genotype-specific modifiers. However, the contribution of parthenogenetic cells to the brain does appear to be influenced by strain background, since a marked improvement in the survival of CFLP, 129 and perhaps SWR parthenogenetic cells in chimeric brains was observed compared with F2 cells.

Endotoxin Alteration of the Mucopolysaccharide Blood Vessel Coating in Rats

1974 ◽  
Vol 32 ◽  
pp. 148-149
Author(s):  
D. E. Philpott ◽  
A. Takahashi
Keyword(s):  
Skeletal Muscle ◽  
Endothelial Cells ◽  
Salivary Gland ◽  
Carotid Artery ◽  
Basement Membrane ◽  
Coronary Vessels ◽  
Ruthenium Red ◽  
E Coli ◽  
Old Rats ◽  
The Brain

Two month, eight month and two year old rats were treated with 10 or 20 mg/kg of E. Coli endotoxin I. P. The eight month old rats proved most resistant to the endotoxin. During fixation the aorta, carotid artery, basil arartery of the brain, coronary vessels of the heart, inner surfaces of the heart chambers, heart and skeletal muscle, lung, liver, kidney, spleen, brain, retina, trachae, intestine, salivary gland, adrenal gland and gingiva were treated with ruthenium red or alcian blue to preserve the mucopolysaccharide (MPS) coating. Five, 8 and 24 hrs of endotoxin treatment produced increasingly marked capillary damage, disappearance of the MPS coating, edema, destruction of endothelial cells and damage to the basement membrane in the liver, kidney and lung.

Severe Head Injury linked to Subsequent Development of Malignant Brain Tumour within a Short Period- A Case Report

2018 ◽  
Vol 3 (2) ◽  
Keyword(s):  
Head Injury ◽  
Brain Tumour ◽  
Severe Head Injury ◽  
Case Reports ◽  
Subsequent Development ◽  
Malignant Brain Tumour ◽  
Tumour Development ◽  
Short Period ◽  
The Brain

There have been a few case reports of head injury leading to brain tumour development in the same region as the brain injury. Here we report a case where the patient suffered a severe head injury with contusion. He recovered clinically with conservative management. Follow up Computed Tomography scan of the brain a month later showed complete resolution of the lesion. He subsequently developed malignant brain tumour in the same region as the original contusion within a very short period of 15 months. Head injury patients need close follow up especially when severe. The link between severity of head injury and malignant brain tumour development needs further evaluation. Role of anti-inflammatory agents for prevention of post traumatic brain tumours needs further exploration.

scholarly journals Lack of Skeletal Muscle Serotonin Impairs Physical Performance

2021 ◽  
Vol 14 ◽  
pp. 117864692110031
Author(s):  
Marion Falabrègue ◽  
Anne-Claire Boschat ◽  
Romain Jouffroy ◽  
Marieke Derquennes ◽  
Haidar Djemai ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Endurance Training ◽  
Physical Performance ◽  
Depressive Disorders ◽  
Tryptophan Metabolism ◽  
Long Distance ◽  
Positive Effects ◽  
Tryptophan Metabolites ◽  
The Brain ◽  
Deficient Mice

Low levels of the neurotransmitter serotonin have been associated with the onset of depression. While traditional treatments include antidepressants, physical exercise has emerged as an alternative for patients with depressive disorders. Yet there remains the fundamental question of how exercise is sensed by the brain. The existence of a muscle–brain endocrine loop has been proposed: according to this scenario, exercise modulates metabolization of tryptophan into kynurenine within skeletal muscle, which in turn affects the brain, enhancing resistance to depression. But the breakdown of tryptophan into kynurenine during exercise may also alter serotonin synthesis and help limit depression. In this study, we investigated whether peripheral serotonin might play a role in muscle–brain communication permitting adaptation for endurance training. We first quantified tryptophan metabolites in the blood of 4 trained athletes before and after a long-distance trail race and correlated changes in tryptophan metabolism with physical performance. In parallel, to assess exercise capacity and endurance in trained control and peripheral serotonin–deficient mice, we used a treadmill incremental test. Peripheral serotonin–deficient mice exhibited a significant drop in physical performance despite endurance training. Brain levels of tryptophan metabolites were similar in wild-type and peripheral serotonin–deficient animals, and no products of muscle-induced tryptophan metabolism were found in the plasma or brains of peripheral serotonin–deficient mice. But mass spectrometric analyses revealed a significant decrease in levels of 5-hydroxyindoleacetic acid (5-HIAA), the main serotonin metabolite, in both the soleus and plantaris muscles, demonstrating that metabolization of tryptophan into serotonin in muscles is essential for adaptation to endurance training. In light of these findings, the breakdown of tryptophan into peripheral but not brain serotonin appears to be the rate-limiting step for muscle adaptation to endurance training. The data suggest that there is a peripheral mechanism responsible for the positive effects of exercise, and that muscles are secretory organs with autocrine-paracrine roles in which serotonin has a local effect.

Differential energetic response of brain vs. skeletal muscle upon glycemic variations in healthy humans

2008 ◽  
Vol 294 (1) ◽  
pp. R12-R16 ◽  
Author(s):  
Kerstin M. Oltmanns ◽  
Uwe H. Melchert ◽  
Harald G. Scholand-Engler ◽  
Maria C. Howitz ◽  
Bernd Schultes ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Underlying Mechanism ◽  
High Energy ◽  
Resonance Spectroscopy ◽  
Energy Status ◽  
High Energy Phosphate ◽  
Available Energy ◽  
Healthy Humans ◽  
High Energy Phosphate Metabolism ◽  
The Brain

The brain regulates all metabolic processes within the organism, and therefore, its energy supply is preserved even during fasting. However, the underlying mechanism is unknown. Here, it is shown, using 31P-magnetic resonance spectroscopy that during short periods of hypoglycemia and hyperglycemia, the brain can rapidly increase its high-energy phosphate content, whereas there is no change in skeletal muscle. We investigated the key metabolites of high-energy phosphate metabolism as rapidly available energy stores by 31P MRS in brain and skeletal muscle of 17 healthy men. Measurements were performed at baseline and during dextrose or insulin-induced hyperglycemia and hypoglycemia. During hyperglycemia, phosphocreatine (PCr) concentrations increased significantly in the brain ( P = 0.013), while there was a similar trend in the hypopglycemic condition ( P = 0.055). Skeletal muscle content remained constant in both conditions ( P > 0.1). ANOVA analyses comparing changes from baseline to the respective glycemic plateau in brain (up to +15%) vs. muscle (up to −4%) revealed clear divergent effects in both conditions ( P < 0.05). These effects were reflected by PCr/Pi ratio ( P < 0.05). Total ATP concentrations revealed the observed divergency only during hyperglycemia ( P = 0.018). These data suggest that the brain, in contrast to peripheral organs, can activate some specific mechanisms to modulate its energy status during variations in glucose supply. A disturbance of these mechanisms may have far-reaching implications for metabolic dysregulation associated with obesity or diabetes mellitus.

Hippocampal glutamine synthetase: insensitivity to glucocorticoids and stress

1990 ◽  
Vol 258 (5) ◽  
pp. E894-E897 ◽  
Author(s):  
G. C. Tombaugh ◽  
R. M. Sapolsky
Keyword(s):  
Skeletal Muscle ◽  
Central Nervous System ◽  
Nervous System ◽  
Glutamine Synthetase ◽  
Glutamate Metabolism ◽  
Glutamatergic Synapses ◽  
Adult Rats ◽  
Glucocorticoid Induction ◽  
The Central Nervous System ◽  
The Brain

Glucocorticoids enhance the neurotoxic potential of several insults to the rat hippocampus that involve overactivation of glutamatergic synapses. These hormones also stimulate the synthesis of glutamine synthetase (GS) in peripheral tissue. Because this enzyme helps regulate glutamate metabolism in the central nervous system, glucocorticoid induction of GS in the brain may underlie the observed synergy. We have measured GS activity in the hippocampus and skeletal muscle (plantaris) of adult rats after bilateral adrenalectomy (ADX), corticosterone (Cort) replacement, or stress. No significant changes in GS were observed in hippocampal tissue, whereas muscle GS was significantly elevated after Cort treatment or stress and was reduced after ADX. These results suggest that Cort-induced shifts in GS activity probably do not explain Cort neurotoxicity, although the stress-induced rise in muscle GS may be relevant to certain types of myopathy.

scholarly journals The physiology of ketosis and the ketogenic diet

2020 ◽  
pp. S94-S97
Author(s):  
TGA Leonard
Keyword(s):  
Skeletal Muscle ◽  
Ketogenic Diet ◽  
The Body ◽  
The Brain ◽  
Fuel Source

Ketones are an important fuel source for the body during periods of starvation and are readily used by the brain, the heart, and skeletal muscle. Ketones may also be produced in response to certain diets. Interest in the use of a diet high in fat and low in carbohydrates in order to induce a state of ketosis has increased in recent years. This review will cover the physiology of ketosis and examine the effects of the ketogenic diet.

scholarly journals THE LEPTIN GENE IS A MARKER FOR THE CELL THERAPY OF METABOLIC SYNDROME

Biomeditsina ◽  
2019 ◽  
pp. 12-22
Author(s):  
N. V. Petrova
Keyword(s):  
Gene Expression ◽  
Metabolic Syndrome ◽  
Cell Therapy ◽  
Bone Marrow Cells ◽  
Liver And Pancreas ◽  
A Cell ◽  
Polymerase Chain ◽  
Lep Gene ◽  
The Brain

It is shown that the level of the Lep gene expression is a marker for B/Ks-Leprᵈᵇ/+ mice, which line serves as an optimal model for describing metabolic syndrome (MS) in preclinical studies. Mice were transplanted with cultured isogenic bone marrow cells (BMC) from heterozygous db/+ donors. The recipients were divided into two groups according to an early or advanced stage of MS development. We analyzed the expression of the Lep gene on the 3rd, 8th and 14th day following the administration of stem BMCs in the brain, liver and pancreas cells by polymerase chain reaction (PCR) in real time. The Lep gene expression was evaluated in terms of the number of cDNA copies. According to our data, leptin is a complete regulator of metabolic processes due to its effect on the hypothalamus, which, together with the hippocampus, controls the production of acetylcholine and insulin in the brain. We have proven the role of the Lep gene as a quantitative criterion for evaluating the effi cacy of a cell therapy in MS.

Development to term of mouse androgenetic aggregation chimeras

Development ◽  
1991 ◽  
Vol 113 (4) ◽  
pp. 1325-1333 ◽  
Author(s):  
J.R. Mann ◽  
C.L. Stewart
Keyword(s):  
Mouse Strain ◽  
Es Cells ◽  
Embryonic Stem ◽  
Cell Types ◽  
Considerable Improvement ◽  
Es Cell ◽  
Partial Explanation ◽  
Developmental Potential ◽  
Skeletal Abnormalities ◽  
Embryonic Tissues

Diploid androgenetic eggs contain two sperm-derived genomes, and only rarely develop to the early somite stage. Also, previous studies have indicated that androgenetic eggs cannot be rescued in aggregation chimeras beyond embryonic stages. Paradoxically, in blastocyst injection chimeras made with androgenetic embryonic stem (ES) cells of the 129/Sv strain, we previously obtained considerable improvement in developmental potential. Although considerable death occurred in utero, overtly normal chimeric fetuses and occasional postnatal chimeras that developed skeletal abnormalities were observed. Consequently, we have re-evaluated the developmental potential of androgenetic aggregation chimeras utilizing androgenetic eggs of the 129/Sv strain, and of the BALB/c and CD-1 strains for comparison. Regardless of strain, androgenetic aggregation chimeras were generally more inviable than previously observed with androgenetic ES cell chimeras, and often the embryoproper was abnormal even when an androgenetic contribution was detected only in the extra-embryonic membranes. This is at least a partial explanation of the greater viability of androgenetic ES cell chimeras, as ES cells do not colonize significantly certain extra-embryonic tissues. Nevertheless, in the 129/Sv strain, occasional development of chimeras to term was obtained, and one chimera that survived postnatally developed identical skeletal abnormalities to those observed previously in androgenetic ES cell chimeras. This result demonstrates that at least one example of paternal imprinting is faithfully conserved in androgenetic ES cells. Also, the postnatal chimerism shows that androgenetic eggs can give rise to terminally differentiated cell types, and are therefore pluripotent. In contrast, only possibly one BALB/c and no CD-1 androgenetic aggregation chimeras developed to term. Therefore, the developmental potential of androgenetic aggregation chimeras is to some extent dependent on mouse strain.

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