Expression of 8-oxoguanine DNA glycosylase (Ogg1) in mouse retina

International audienc

Registration of 3D fetal neurosonography and MRI.

We propose a method for registration of 3D fetal brain ultrasound with a reconstructed magnetic resonance fetal brain volume. This method, for the first time, allows the alignment of models of the fetal brain built from magnetic resonance images with 3D fetal brain ultrasound, opening possibilities to develop new, prior information based image analysis methods for 3D fetal neurosonography. The reconstructed magnetic resonance volume is first segmented using a probabilistic atlas and a pseudo ultrasound image volume is simulated from the segmentation. This pseudo ultrasound image is then affinely aligned with clinical ultrasound fetal brain volumes using a robust block-matching approach that can deal with intensity artefacts and missing features in the ultrasound images. A qualitative and quantitative evaluation demonstrates good performance of the method for our application, in comparison with other tested approaches. The intensity average of 27 ultrasound images co-aligned with the pseudo ultrasound template shows good correlation with anatomy of the fetal brain as seen in the reconstructed magnetic resonance image

CX3CR1+ CD115+ CD135+ common macrophage/DC precursors and the role of CX3CR1 in their response to inflammation

CX3CR1 expression is associated with the commitment of CSF-1R+ myeloid precursors to the macrophage/dendritic cell (DC) lineage. However, the relationship of the CSF-1R+ CX3CR1+ macrophage/DC precursor (MDP) with other DC precursors and the role of CX3CR1 in macrophage and DC development remain unclear. We show that MDPs give rise to conventional DCs (cDCs), plasmacytoid DCs (PDCs), and monocytes, including Gr1+ inflammatory monocytes that differentiate into TipDCs during infection. CX3CR1 deficiency selectively impairs the recruitment of blood Gr1+ monocytes in the spleen after transfer and during acute Listeria monocytogenes infection but does not affect the development of monocytes, cDCs, and PDCs

ATM et OGG1 (ataxia telangiectasia mutated et 8-oxoguanine ADN glycosylase) (Etude de deux enzymes majeures impliquées dans la reconnaissance des lésions de l'ADN dans l'oeil de souris)

La rétine est un tissu fortement exposé au stress oxydatif de part son activité physiologique (exposition aux rayons lumineux, consommation d'oxygène, activité métabolique, phagocytose...). Toutes ces particularités sont à l'origine de la production de ROS qui provoquent des nombreux dommages comme l'oxydation des bases et les cassures double brin. Ce travail présente différentes protéines de la réparation de l'ADN (ATM et OGG1) intervenant dans différentes voies de reconnaissance suivant le type de dommages rencontrés. La protéine ATM qui détecte des cassures double brin présente une localisation différente dans les photorécepteurs et les cellules granulaires du cervelet. La protéine OGG1 permettant la reconnaissance et l'excision de la 8-oxoG est présente et active dans les cellules rétiniennes. Chez les souris déficientes pour chacune de ces protéines, aucune dégénérescence rétinienne n'est observée. Cependant, des dysplasies de la neurorétine et de l'EPR sont mises en évidence.The retina is particularly susceptible to oxidative stress due to high oxygen consumption and metabolic rates. The specific characteristics of the retina (high levels of oxygen consumption, light, polyunsatured fatty acids...) lead to free radical, cell damages, ageing and diseases. Therefore, all these processes can contribute to the formation of oxidative DNA damage in the retinal cells. A difference between the localization patterns of the active and inactive forms of ATM in photoreceptor and granular cells was observed. This suggests that ATMp (activated form) may be involved in both the protection of cells from oxidative damage and the maintenance of ocular cell structure and function. OGG1, responsible for the recognition and excision of the 8-oxoG, is highly expressed in neuroretina and non-neuronal cells of the eye and a 8-oxoG DNA-glycosylase activity is detected in this tissue. Moreover, there is no retinal degeneration in Atm-/- and Ogg1-/- mice.PARIS5-BU Méd.Cochin (751142101) / SudocSudocFranceF

Modulation of taste receptor mRNA expression, inflammation and junction permeability in the lingual papillae in diet-induced obese mice

IF 4.066International audienc

Tunisian grape seed extracts decrease LPS-induced inflammation in murine macrophages

IF 4.066International audienc

Orosensory detection of dietary fat is decreased in CB1R-/- mice

IF 4.066International audienc

Zizyphin modulates sugar and fat taste perception: evidence from behavioural and calcium signaling studies

IF 4.066International audienc

Orosensory Detection of Dietary Fatty Acids Is Altered in CB1R−/− Mice

International audienceObesity is one of the major public health issues, and its prevalence is steadily increasing all the world over. The endocannabinoid system (ECS) has been shown to be involved in the intake of palatable food via activation of cannabinoid 1 receptor (CB₁R). However, the involvement of lingual CB₁R in the orosensory perception of dietary fatty acids has never been investigated. In the present study, behavioral tests on CB₁R-/- and wild type (WT) mice showed that the invalidation of Cb₁r gene was associated with low preference for solutions containing rapeseed oil or a long-chain fatty acid (LCFA), such as linoleic acid (LA). Administration of rimonabant, a CB₁R inverse agonist, in mice also brought about a low preference for dietary fat. No difference in CD36 and GPR120 protein expressions were observed in taste bud cells (TBC) from WT and CB₁R-/- mice. However, LCFA induced a higher increase in [Ca2+]i in TBC from WT mice than that in TBC from CB₁R-/- mice. TBC from CB₁R-/- mice also exhibited decreased Proglucagon and Glp-1r mRNA and a low GLP-1 basal level. We report that CB₁R is involved in fat taste perception via calcium signaling and GLP-1 secretion