Search results for "Homeostasis"
showing 10 items of 630 documents
Effects of repeated short episodes of environmental acidification on Atlantic salmon (Salmo salar) from a landlocked population
2020
Abstract Chronic or repeated exposure to environmental contaminants may result in allostatic overload, a physiological situation in which the costs of coping affect long-term survival and reproductive output. Continuous measurements in Otra, the largest river in southern Norway, show the occurrence of repeated 24–48 h episodes of acidification. This work investigates the impact of repeated short acidification episodes on a unique land-locked population of normally anadromous Atlantic salmon (“Bleke”). This was done by recording physiological measures of stress and allostatic load in fish exposed for 7 days to continuous or repeated episodes of simulated environmental acidification or untrea…
Lysine synthesis control in Corynebacterium glutamicum RC 115 in mixed substrate (glucose-acetate) medium.
2003
The effect of acetate as a glucose co-substrate on growth, lysine synthesis and experimental lysine yield from carbon substrates by Corynebacterium glutamicum RC 115 was investigated. It was found that low amounts of acetate, injected with a glucose-acetate pulse into the steady-state continuous culture in bioreactor, caused a slight decrease in the specific rates of glucose uptake and bacterial growth, but a significant increase in the cell specific rate of lysine synthesis and an increase in lysine yield. In contrast, acetate injected in high amounts was followed by a drastic decrease in the values of these parameters. A strong increase in experimental lysine yield under the latter condit…
A new actor involved in hypothalamic glucose detection : the Transient Receptor Potential Canonical (TRPC) channels
2015
Hyperglycemia is detected and integrated by the mediobasal hypothalamus (MBH) which, in turn, inhibits food intake and triggers insulin secretion. The MBH houses specialized glucose-sensitive (GS) neurons, which directly or indirectly modulate their electrical activity in response to changes in glucose level. In a first study, we hypothesized that indirect detection of glucose by MBH GS neurons involves the secretion of endozepine by astrocytes, a gliotransmitter known to inhibit food intake in response to hyperglycemia. The present work shows that endozepines selectively activate anorexigenic MBH pro-opiomelanotortine (POMC) neurons. In the second study, we show that the direct detection o…
Long-Term Behavioral Programming Induced by Peripuberty Stress in Rats Is Accompanied by GABAergic-Related Alterations in the Amygdala
2014
Stress during childhood and adolescence is a risk factor for psychopathology. Alterations in γ-aminobutyric acid (GABA), the main inhibitory neurotransmitter in the brain, have been found following stress exposure and fear experiences and are often implicated in anxiety and mood disorders. Abnormal amygdala functioning has also been detected following stress exposure and is also implicated in anxiety and social disorders. However, the amygdala is not a unitary structure; it includes several nuclei with different functions and little is known on the potential differences the impact of early life stress may have on this system within different amygdaloid nuclei. We aimed here to evaluate pote…
Glial Protection Against Neuronal Damage
1997
Glial homeostatic mechanisms are involved in neuronal protection during the early phase of cerebral ischemia. These protective effects include, among others, glutamate uptake and the regulation of pH in the extracellular space of the brain. Uptake of glutamate goes along with glial swelling, as does the elimination of protons from the glial cytosol. Five transport systems interact in order to maintain a normal intra- and extracellular pH in the brain.
IMPROVEMENT IN REDOX HOMEOSTASIS AFTER CYTOREDUCTIVE SURGERY IN COLORECTAL ADENOCARCINOMA
2021
Colorectal cancer (CRC) as one the most common cancer type is associated with oxidative stress. Surgery is the only curative modality for early-stage CRC. The aim of this study was to evaluate the oxidative damage biomarkers as well as enzymatic and nonenzymatic antioxidants in patients with CRC before and after tumor resection and in healthy controls. 60 patients with stage I/II colorectal adenocarcinoma and 43 healthy controls were recruited in this study. We measured plasma levels of oxidative damage biomarkers, including advanced oxidation protein products (AOPP), advanced glycation end products (AGEs), malondialdehyde (MDA), and oxidized low-density lipoprotein (ox-LDL) at baseline and…
The adenine nucleotide content of rat liver during infusions of carbohydrates and polyols
1972
Injection of large doses of fructose, sorbitol, or a mixture of glucose, fructose and xylitol in rats causes a drop of liver ATP, total adenine nucleotides and Pi and a rise of AMP, which is in agreement with data from the literature. These changes are considered as a transient disturbance of homeostasis by compounds which are rapidly phosporylated in the liver. This is confirmed by the fact that during continuous infusion of these and other compounds at doses of 1,5 g · kg−1 · h−1 there was no such change. It is concluded that infusions of fructose or of the other carbohydrates tested with rates not exceeding those recommended for parenteral nutrition (0,5 g · kg−1 · h−1) are not likely to…
A stress-responsive miRNA regulates BMP signaling to maintain tissue homeostasis
2021
Adult organisms must sense and adapt to environmental fluctuations. In high-turnover tissues such as the intestine, these adaptive responses require rapid changes in gene expression that, in turn, likely involve posttranscriptional gene control. However, intestinal-tissue-specific microRNA (miRNA)-mediated regulatory pathways remain unexplored. Here, we report the role of an intestinal-specific miRNA, miR-958, that non-cell autonomously regulates stem cell numbers during tissue homeostasis and regeneration in the Drosophila adult midgut. We identify its downstream target cabut, the Drosophila ortholog of mammalian KLF10/11 transcription factors, which mediates this miR-958 function by promo…
Effects of a Resistance Training Protocol on Physical Performance, Body Composition, Bone Metabolism, and Systemic Homeostasis in Patients Diagnosed …
2022
Parkinson’s disease (PD) is a neurodegenerative disorder characterized by motor impairments and it is correlated with loss of bone mineral density. This study aimed to analyze the effects of resistance training on bone metabolism, systemic homeostasis, body composition, and physical performance in people with PD. Thirteen subjects (age 64.83 ± 5.70) with PD diagnosis were recruited. Participants performed neuromuscular tests, body composition assessment, and blood sample analysis at baseline, and after an 11 weeks-training period. Each training session lasted 90 min, three times a week. The participants had significant improvements in the timed up and go (p < 0.01), sit to stand (p < …
Overview and Book Plan
2013
This chapter provides an introduction to the biology and pathology of molecular chaperones, many of which are heat-shock proteins, involved in protein homeostasis and other unrelated functions. When chaperones are defective structurally and/or functionally they may cause disease. These diseases in which chaperones play an etiologic-pathogenic role are the chaperonopathies. The chapter also gives a clinical-pathological overview of chaperonopathies and guidelines for their identification and diagnosis. It briefly describes how to detect and characterize a chaperonopathy in a patient. Chaperones can be useful biomarkers for disease diagnosis and monitoring, including evaluation of prognosis a…