Consulta: creatorFacets:"Lignot, Jehan-herve"
Registros recuperados: 4
Data/hora: 10/06/2024 18:12:45

Effects of fasting and re-alimentation on gill and intestinal morphology and indicators of osmoregulatory capacity in genetically selected sea bass (Dicentrarchus labrax) populations with contrasting tolerance to fasting
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Alix, Maud; Blondeau-bidet, Eva; Grousset, Evelyse; Shiranghi, Ainaz; Vergnet, Alain; Guinand, Bruno; Chatain, Beatrice; Boulo, Viviane; Lignot, Jehan-herve.
Fasting and refeeding occur naturally in predators but this is largely ignored when dealing with farmed fish. Therefore, the effects of 3-week fasting and re-alimentation (2.5% of the individual body mass) were investigated using two genetically selected populations (F2 generation) of 250 g juvenile sea bass (Dicentrarchus labrax L.). Blood osmolarity, gill and intestinal morphology and expression of the sodium pump (Na+, K+-ATPase, NKA) were studied on two phenotypes showing different degrees of body mass loss during food deprivation: one group losing body mass rapidly during fasting (F +) and the other one limiting body mass loss during the same period (F-).  Blood osmotic pressure significantly decreases due to re-alimentation in both groups, but this...
Tipo: Text
Ano: 2017
URL: http://archimer.ifremer.fr/doc/00354/46521/46285.pdf

Osmoregulation, bioenergetics and oxidative stress in coastal marine invertebrates: raising the questions for future research
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Rivera-ingraham, Georgina A.; Lignot, Jehan-herve.
Osmoregulation is by no means an energetically cheap process, and its costs have been extensively quantified in terms of respiration and aerobic metabolism. Common products of mitochondrial activity are reactive oxygen and nitrogen species, which may cause oxidative stress by degrading key cell components, while playing essential roles in cell homeostasis. Given the delicate equilibrium between pro- and antioxidants in fueling acclimation responses, the need for a thorough understanding of the relationship between salinity-induced oxidative stress and osmoregulation arises as an important issue, especially in the context of global changes and anthropogenic impacts on coastal habitats. This is especially urgent for intertidal/estuarine organisms, which may...
Tipo: Text
Palavras-chave: Hyper-/hypo-osmoregulator; Hyper-/iso-osmoregulators; Osmoconformers; Antioxidants; Free radicals; Hypometabolism; Mitochondria.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00625/73717/74820.pdf

Osmoregulation and salinity-induced oxidative stress: is oxidative adaptation determined by gill function?
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Rivera-ingraham, Georgina A.; Barri, Kiam; Boel, Melanie; Farcy, Emilie; Charles, Anne-laure; Geny, Bernard; Lignot, Jehan-herve.
Osmoregulating decapods such as the Mediterranean green crab Carcinus aestuarii possess two groups of spatially segregated gills: anterior gills serve mainly respiratory purposes, while posterior gills contain osmoregulatory structures. The co-existence of similar tissues serving different functions allows the study of differential adaptation, in terms of free radical metabolism, upon salinity change. Crabs were immersed for 2 weeks in seawater (SW, 37 ppt), diluted SW (dSW, 10 ppt) and concentrated SW (cSW, 45 ppt). Exposure to dSW was the most challenging condition, elevating respiration rates of whole animals and free radical formation in hemolymph (assessed fluorometrically using C-H(2)DFFDA). Further analyses considered anterior and posterior gills...
Tipo: Text
Palavras-chave: Antioxidant defense; Carcinus aestuarii; ROS production; Osmoregulation.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00626/73816/74410.pdf

Salinity stress from the perspective of the energy-redox axis: Lessons from a marine intertidal flatworm
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Rivera-ingraham, Georgina A.; Nommick, Aude; Blondeau-bidet, Eva; Ladurner, Peter; Lignot, Jehan-herve.
In the context of global change, there is an urgent need for researchers in conservation physiology to understand the physiological mechanisms leading to the acquisition of stress acclimation phenotypes. Intertidal organisms continuously cope with drastic changes in their environmental conditions, making them outstanding models for the study of physiological acclimation. As the implementation of such processes usually comes at a high bioenergetic cost, a mitochondrial/oxidative stress approach emerges as the most relevant approach when seeking to analyze whole-animal responses. Here we use the intertidal flatworm Macrostomum lignano to analyze the bioenergetics of salinity acclimation and its consequences in terms of reactive oxygen/nitrogen species...
Tipo: Text
Palavras-chave: Energetic balance; Flatworms; Live-imaging; Mitochondrial membrane potential; Osmoregulation; RNS; ROS.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00625/73743/74411.pdf