Changes in protein content and in vivo incorporation of [35S]methionine into protein of discrete brain areas of the rat over puberty: Sexual differences

1973 ◽  
Vol 60 (1) ◽  
pp. 209-218 ◽  
Author(s):  
M.B. ter Haar ◽  
P.C.B. MacKinnon
2021 ◽  
Vol 22 (13) ◽  
pp. 7232
Author(s):  
Gloria Lazzeri ◽  
Carla L. Busceti ◽  
Francesca Biagioni ◽  
Cinzia Fabrizi ◽  
Gabriele Morucci ◽  
...  

Norepinephrine (NE) neurons and extracellular NE exert some protective effects against a variety of insults, including methamphetamine (Meth)-induced cell damage. The intimate mechanism of protection remains difficult to be analyzed in vivo. In fact, this may occur directly on target neurons or as the indirect consequence of NE-induced alterations in the activity of trans-synaptic loops. Therefore, to elude neuronal networks, which may contribute to these effects in vivo, the present study investigates whether NE still protects when directly applied to Meth-treated PC12 cells. Meth was selected based on its detrimental effects along various specific brain areas. The study shows that NE directly protects in vitro against Meth-induced cell damage. The present study indicates that such an effect fully depends on the activation of plasma membrane β2-adrenergic receptors (ARs). Evidence indicates that β2-ARs activation restores autophagy, which is impaired by Meth administration. This occurs via restoration of the autophagy flux and, as assessed by ultrastructural morphometry, by preventing the dissipation of microtubule-associated protein 1 light chain 3 (LC3) from autophagy vacuoles to the cytosol, which is produced instead during Meth toxicity. These findings may have an impact in a variety of degenerative conditions characterized by NE deficiency along with autophagy impairment.


1988 ◽  
Vol 255 (4) ◽  
pp. H729-H735 ◽  
Author(s):  
M. Sautel ◽  
J. Sacquet ◽  
M. Vincent ◽  
J. Sassard

Several indirect evidences of alterations in the central catecholaminergic structures were obtained in genetically hypertensive rats. Because they could be of pathogenetic value, we measured, in the present work, the in vivo turnover (TO) of norepinephrine (NE) in brain areas of 5- and 22-wk-old genetically hypertensive (LH) rats of the Lyon strain, and their simultaneously selected normotensive (LN) and low blood pressure (LL) controls. Among the changes observed, the increased TO of NE in the A2 and A6 regions of 5-wk-old LH rats and its decrease in the posteroventral hypothalamic nucleus of 22-wk-old LH animals appeared likely to compensate for hypertension. On the contrary, the decreased TO of NE in the anterior hypothalamic nucleus observed at 5 wk and in the A6 and A1 areas at 22 wk of age in LH rats could participate in the development or the maintenance of hypertension. Above all, it was postulated that the increased TO of NE found in the A7 region of 5-wk-old LH rats could play a primary role in the pathogenesis of hypertension in the Lyon model.


2012 ◽  
Vol 18 (2) ◽  
pp. 54-55
Author(s):  
Lucas Silva Tortorelli ◽  
Maria Cristina Guerra ◽  
Fabiana Galland ◽  
Carollina Da Ré ◽  
Elisa Negri ◽  
...  

Peptides ◽  
1989 ◽  
Vol 10 (4) ◽  
pp. 717-720 ◽  
Author(s):  
Holger Stark ◽  
J.Peter H. Burbach ◽  
Arno A.M. Van Der Kleij ◽  
David De Wied
Keyword(s):  

1963 ◽  
Vol 117 (1) ◽  
pp. 105-125 ◽  
Author(s):  
Manuel E. Kaplan ◽  
James H. Jandl

Studies were undertaken in man and in the rat comparing the effects of rheumatoid factors and immune antiglobulins on red cells sensitized with incomplete antibodies. The interaction of immune antiglobulins with sensitized red cells produced (a) agglutination in vitro and (b) an accelerated sequestration of the sensitized cells in vivo. In contrast, rheumatoid macroglobulins, although capable of agglutinating Rh-sensitized red cells in vitro, did not modify their destruction in vivo. The failure of rheumatoid factors to function as antiglobulins in vivo appears to reflect their non-reactivity with sensitized cells in whole serum. It is suggested: (a) that the native (7S) gamma globulins of plasma competitively inhibit rheumatoid factors from reacting with fixed antibody in the blood stream; (b) that if these macroglobulins do indeed have pathogenetic activity, this may be limited to body fluids of low protein content.


Author(s):  
Tomas T. Roos ◽  
Megg G. Garcia ◽  
Isak Martinsson ◽  
Rana Mabrouk ◽  
Bodil Israelsson ◽  
...  

AbstractThe amyloid-beta peptide (Aβ) is thought to have prion-like properties promoting its spread throughout the brain in Alzheimer’s disease (AD). However, the cellular mechanism(s) of this spread remains unclear. Here, we show an important role of intracellular Aβ in its prion-like spread. We demonstrate that an intracellular source of Aβ can induce amyloid plaques in vivo via hippocampal injection. We show that hippocampal injection of mouse AD brain homogenate not only induces plaques, but also damages interneurons and affects intracellular Aβ levels in synaptically connected brain areas, paralleling cellular changes seen in AD. Furthermore, in a primary neuron AD model, exposure of picomolar amounts of brain-derived Aβ leads to an apparent redistribution of Aβ from soma to processes and dystrophic neurites. We also observe that such neuritic dystrophies associate with plaque formation in AD-transgenic mice. Finally, using cellular models, we propose a mechanism for how intracellular accumulation of Aβ disturbs homeostatic control of Aβ levels and can contribute to the up to 10,000-fold increase of Aβ in the AD brain. Our data indicate an essential role for intracellular prion-like Aβ and its synaptic spread in the pathogenesis of AD.


2018 ◽  
Author(s):  
Rebeca Lapresa ◽  
Jesús Agulla ◽  
Irene Sánchez-Morán ◽  
Juan P. Bolaños ◽  
Angeles Almeida

ABSTRACTThe p53 tumor suppressor protein, a key regulator of cell apoptosis, has been described to accumulate in affected brain areas from Alzheimer’s disease (AD) patients. However, whether p53 plays any role in AD pathogenesis remains unknown. Here, we found that exposure of neurons to oligomers of the amyloidogenic fragment 25-35 of the Aß peptide (Aβ25-35) activated Cdk5, which promoted p53 protein phosphorylation and stabilization. Moreover, Aβ25-35-mediated mitochondrial dysfunction and neuronal apoptosis were prevented by both genetic and pharmacological inhibition of either p53 or Cdk5 activities. To confirm this mechanism in vivo, Aβ25-35 was stereotaxically injected in the cerebral right ventricle of mice, a treatment that caused p53 protein accumulation, dendrite disruption and neuronal death. Furthermore, these effects were prevented in p53 knockout mice or by pharmacologically inhibiting p53. Thus, Aβ25-35 triggers Cdk5 activation to induce p53 phosphorylation and stabilization, which leads to neuronal damage. Inhibition of the Cdk5-p53 pathway may therefore represent a novel therapeutic strategy against Aβ-induced neurodegeneration.


1989 ◽  
Vol 256 (3) ◽  
pp. R659-R665 ◽  
Author(s):  
Y. Fong ◽  
L. L. Moldawer ◽  
M. Marano ◽  
H. Wei ◽  
A. Barber ◽  
...  

Macrophage secretory products are suspected to participate in the severe lean tissue wasting related to chronic illness. The protein metabolic effects of chronic, 7-day cachectin/tumor necrosis factor (cachectin) or interleukin 1 alpha (IL-1 alpha) administration in vivo were studied in male Wistar rats that were 1) freely fed, 2) pair fed, 3) total protein and calorie starved, 4) twice daily lipopolysaccharide (LPS) administered, 5) twice daily cachectin administered, and 6) twice daily IL-1 alpha administered. LPS, cachectin, or IL-1 alpha administration produced anorexia; weight loss in these groups was comparable to respective pair-fed animals. However, LPS, cachectin, or IL-1 alpha accelerated peripheral protein wasting while preserving liver protein content, unlike the pattern in the pair-fed or starved animals in which loss of liver proteins and relative preservation of skeletal muscle protein were observed. The decrease in skeletal muscle protein content in LPS- or cytokine-treated animals was associated with coordinate decreases in muscle mRNA levels for the myofibrillar proteins myosin heavy chain, myosin light chain, actin, and in the 18S and 28S subunits of ribosomal RNA. We conclude that chronic exposure to the cytokines, IL-1 alpha or cachectin, can simulate those body and muscle protein changes seen in experimental LPS administration or chronic disease and markedly differ from the pattern of protein redistribution due to caloric restriction.


2004 ◽  
Vol 1 (3) ◽  
pp. 269-276 ◽  
Author(s):  
Bolin Qin ◽  
Masaru Nagasaki ◽  
Ming Ren ◽  
Gustavo Bajotto ◽  
Yoshiharu Oshida ◽  
...  

Previous studies have shown that the traditional herbal complex Gosha-jinki-gan (GJG) improves diabetic neuropathy and insulin resistance. The present study was undertaken to elucidate the molecular mechanisms related with the long-term effects of GJG administration on insulin actionin vivoand the early steps of insulin signaling in skeletal muscle in streptozotocin (STZ) diabetes. Rats were randomized into five subgroups: (1) saline treated control, (2) GJG treated control, (3) 2-unit insulin + saline treated diabetic, (4) saline + GJG treated diabetic and (5) 2-unit insulin + GJG treated diabetic groups. After seven days of treatment, euglycemic clamp experiment at an insulin infusion rate of 6 mU/kg/min was performed in overnight fasted rats. Despite the 2-unit insulin treatment, the metabolic clearance rates of glucose (MCR, ml/kg/min) in diabetic rats were significantly lower compared with the controls (11.4 ± 1.0 vs 44.1 ± 1.5;P< 0.001), and were significantly improved by insulin combined with GJG or GJG alone (26 ± 3.2 and 24.6 ± 2.2,P< 0.01, respectively). The increased insulin receptor (IR)-β protein content in skeletal muscle of diabetic rats was not affected by insulin combined with GJG administration. However, the decreased insulin receptor substrate-1 (IRS-1) protein content was significantly improved by treatment with GJG. Additionally, the increased tyrosine phosphorylation levels of IR-β and IRS-1 were significantly inhibited in insulin combined with GJG treated diabetes. The present results suggest that the improvement of the impaired insulin sensitivity in STZ-diabetic rats by administration of GJG may be due, at least in part, to correction in the abnormal early steps of insulin signaling in skeletal muscle.


1964 ◽  
Vol 207 (6) ◽  
pp. 1215-1220 ◽  
Author(s):  
Alisa Gutman ◽  
Eleazar Shafrir

Rat adipose tissue from different body sites was shown to contain uridine diphosphoglucose (UDPG)-transglucosylase activity, which on the basis of protein content was comparable to or higher than that reported for muscle or liver. In epididymal adipose tissue, the activity of UDPG-glycogen transglucosylase and phosphorylase, as well as the content of glycogen per wet weight, decreased with increasing age of the animals in parallel with the decrease of tissue protein content. On prolonged fast the activity of UDPG-glycogen transglucosylase and phosphorylase per milligram protein dropped by 25–50% of the control value. On refeeding, the extent of changes was variable but, in general, at 24 hr control or higher levels of activity were reached and at 48 hr the activities were elevated. The ratio of glucose 6-phosphate independent activity of UDPG-glycogen transglucosylase to total activity was not affected by fasting and refeeding or by the administration of glucose with insulin. In adrenalectomized rats, with high adipose tissue glycogen, no change in UDPG-glycogen transglucosylase was found, whereas the levels of phosphorylase were elevated. Epinephrine in vivo and in vitro did not affect the activity of UDPG-glycogen transglucosylase of adipose tissue.


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