Search results for "Micro"

The close link between the fetal programming imprinting and neurodegeneration in adulthood: The key role of “hemogenic endothelium” programming

2021

The research on neurodegenerative diseases (NeuroDegD) has been traditionally focused on later life stages. There is now an increasing evidence, that they may be programmed during early development. Here, we propose that NeuroDegD are the result of the complex process of imprinting on fetal hemogenic endothelium, from which the microglial cells make to origin. The central role of placenta and epigenetic mechanisms (methylation of DNA, histone modifications and regulation by non-coding RNAs) in mediating the short and long-term effects has been also described. Precisely, it reports their role in impacting plasticity and memory of microglial cells. In addition, we also underline the necessity…

Microglia in Alzheimer’s Disease: Activated, Dysfunctional or Degenerative

2018

Microglial activation has been considered a crucial player in the pathological process of multiple human neurodegenerative diseases. In some of these pathologies, such as Amyotrophic Lateral Sclerosis or Multiple Sclerosis, the immune system and microglial cells (as part of the cerebral immunity) play a central role. In other degenerative processes, such as Alzheimer’s disease (AD), the role of microglia is far to be elucidated. In this “mini-review” article, we briefly highlight our recent data comparing the microglial response between amyloidogenic transgenic models, such as APP/PS1 and AD patients. Since the AD pathology could display regional heterogeneity, we focus our work at the hipp…

Electrical activity controls area-specific expression of neuronal apoptosis in the mouse developing cerebral cortex

2017

Programmed cell death widely but heterogeneously affects the developing brain, causing the loss of up to 50% of neurons in rodents. However, whether this heterogeneity originates from neuronal identity and/or network-dependent processes is unknown. Here, we report that the primary motor cortex (M1) and primary somatosensory cortex (S1), two adjacent but functionally distinct areas, display striking differences in density of apoptotic neurons during the early postnatal period. These differences in rate of apoptosis negatively correlate with region-dependent levels of activity. Disrupting this activity either pharmacologically or by electrical stimulation alters the spatial pattern of apoptos…

2019

Traumatic brain injury (TBI) is a frequent pathology and associated with poor outcome in the aged population. We recently observed accelerated cerebral inflammation in aged mice in response to TBI. Candesartan is a potent specific inhibitor of angiotensin II receptor type 1 (AT1) which limits cerebral inflammation and brain damage in juvenile animals after experimental TBI. In the present study, we show significantly lower posttraumatic AT1 mRNA levels in aged (21 months) compared to young (2 months) mice. Despite low cerebral At1 expression, pharmacologic blockade by treatment with candesartan (daily, beginning 30 minutes after experimental TBI by controlled cortical impact [CCI]) was high…

Peripapillary fluorescence lifetime reveals age-dependent changes using fluorescence lifetime imaging ophthalmoscopy in rats

2017

Abstract Many fundus diseases accompany fundus autofluorescence change. Fluorescence lifetime imaging ophthalmoscope (FLIO) is a latest technique in imaging fundus autofluorescence. With FLIO, the fundus fluorescence lifetime (FLT) is recorded topographically, assisting to diagnose and monitor multiple fundus diseases. The purpose of this study was to evaluate the repeatability of FLT using FLIO on adult rats and to analyze the age-dependency of the peripapillary FLT of the fundus in a short spectral channel (498–560 nm) and a long spectral channel (560–720 nm). Sprague Dawley rats (n of eyes = 10) were used for repeatability experiments. Age-dependent changes were investigated in young (tw…

Gut microbiota and osteoarthritis management: An expert consensus of the European society for clinical and economic aspects of osteoporosis, osteoart…

2019

Berenbaum, Francis/0000-0001-8252-7815; Dennison, Elaine/0000-0002-3048-4961; Bindels, Laure B./0000-0003-3747-3234; Cooper, Cyrus/0000-0003-3510-0709 WOS:000491638300002 PubMed ID: 31437484 The prevalence of osteoarthritis (OA) increases not only because of longer life expectancy but also because of the modern lifestyle, in particular physical inactivity and diets low in fiber and rich in sugar and saturated fats, which promote chronic low-grade inflammation and obesity. Adverse alterations of the gut microbiota (GMB) composition, called microbial dysbiosis, may favor metabolic syndrome and inflammaging, two important components of OA onset and evolution. Considering the burden of OA and t…

A novel microglial subset plays a key role in myelinogenesis in developing brain.

2017

Microglia are resident macrophages of the central nervous system that contribute to homeostasis and neuroinflammation. Although known to play an important role in brain development, their exact function has not been fully described. Here, we show that in contrast to healthy adult and inflammation-activated cells, neonatal microglia show a unique myelinogenic and neurogenic phenotype. A CD11c(+) microglial subset that predominates in primary myelinating areas of the developing brain expresses genes for neuronal and glial survival, migration, and differentiation. These cells are the major source of insulin-like growth factor 1, and its selective depletion from CD11c(+) microglia leads to impa…

Tillage intensity and pasture in rotation effectively shape soil microbial communities at a landscape scale

2018

International audience; Soil microorganisms are essential to agroecosystem functioning and services. Yet, we still lack information on which farming practices can effectively shape the soil microbial communities. The aim of this study was to identify the farming practices, which are most effective at positively or negatively modifying bacterial and fungal diversity while considering the soil environmental variation at a landscape scale. A long-term research study catchment (12 km2 ) representative of intensive mixed farming (livestock and crop) in Western Europe was investigated using a regular grid for soil sampling (n = 186). Farming systems on this landscape scale were described in terms…

Vascular biotransformation of organic nitrates is independent of cytochrome P450 monooxygenases

2020

Background and Purpose Organic nitrates such as nitroglycerin (NTG) or pentaerythritol tetranitrate (PETN) have been used for over a century in the treatment of angina or ischaemic heart disease. These compounds are prodrugs which release their nitrovasodilators upon enzymic bioactivation by aldehyde dehydrogenase (ALDH2) or cytochromes P450 (CYP). Whereas ALDH2 is known to directly activate organic nitrates in vessels, the contribution of vascular CYPs is unknown and was studied here. Experimental Approach As all CYPs depend on cytochrome P450 reductase (POR) as electron donor, we generated a smooth muscle cell-specific, inducible knockout mouse of POR (smcPOR−/−) to investigate the contri…

Birth Mode-Related Differences in Gut Microbiota Colonization and Immune System Development.

2018

<b><i>Background:</i></b> The process of early gut colonization is extremely variable among individuals and is influenced by numerous factors. Among these, the mode of birth will strongly shape the early microbial exposure and immune environment of the neonate. <b><i>Summary:</i></b> Here, I review how the concomitant processes of microbiota and immune system development are altered by C-section delivery and the effects of such alterations on long-term health. <b><i>Key messages:</i></b> C-section delivery impinges on microbiota and immune system development through various means: (i) if labor is lacking, intrauterine i…