Project description:Excessive lighting is integral to dentists' daily routines but can impair their vision, affecting personal and professional performance. Most studies focus on acute photodamage, neglecting chronic photoinjury from dental lighting and its impact on the blood-retinal barrier homeostasis. An epidemiological survey involving 14,523 individuals reveals dentists have a higher prevalence of vision-related issues compared to other occupations. Subsequently, chronic photodamage models in rats were created to accurately simulate dental working conditions. Using systematic imaging and gene analysis, including OCT, tissue clearing technology and RNA-sequencing, dental lighting was found to disrupted both inner and outer blood-retinal barriers, reduced retinal blood vessels, and promoted perivascular macrophage recruitment. Moreover, the activation of inflammatory-related pathways such as NF-κB signalling resulted in the damage of vision-related functional structures in the retina. Notably, among the three commonly used dental lighting sources, low-intensity halogen light possessed a minimal impact on the retina, while blue and white LEDs have remarkable negative effects on blood-retinal barrier homeostasis. This study explored the potential mechanism of dental lighting environment inducing the disruption of blood-retinal barrier homeostasis, and provided essential guidance for dental professionals in selecting light sources, which is conducive to reducing the risk of occupational ocular diseases among dentists.
Project description:The skin barrier consists of multiple lipid-enriched layers. Sodium lauryl sulfate is a well-known substance that can disrupt the skin barrier. The mechanisms underlying the barrier repair process, especially the influence of topical sodium lauryl sulfate treatment in the barrier recovery phase remain unresolved. To understand the process of reconstruction of the intercellular lipid layer of the skin after acute barrier disruption by sodium lauryl sulfate treatment in vivo.
Project description:Morphine and its pharmacological derivatives are the most prescribed analgesics for moderate to severe pain management. However, chronic use of morphine reduces pathogen clearance and induces bacterial translocation across the gut barrier. The enteric microbiome has been shown to play a critical role in the preservation of the mucosal barrier function and metabolic homeostasis. Here, we show for the first time, using bacterial 16s rDNA sequencing, that chronic morphine treatment significantly alters the gut microbial composition and induces preferential expansion of the gram-positive pathogenic and reduction of bile-deconjugating bacterial strains. A significant reduction in both primary and secondary bile acid levels was seen in the gut, but not in the liver with morphine treatment. Morphine induced microbial dysbiosis and gut barrier disruption was rescued by transplanting placebo-treated microbiota into morphine-treated animals, indicating that microbiome modulation could be exploited as a therapeutic strategy for patients using morphine for pain management. In this study, we establish a link between the two phenomena, namely gut barrier compromise and dysregulated bile acid metabolism. We show for the first time that morphine fosters significant gut microbial dysbiosis and disrupts cholesterol/bile acid metabolism. Changes in the gut microbial composition is strongly correlated to disruption in host inflammatory homeostasis13,14 and in many diseases (e.g. cancer/HIV infection), persistent inflammation is known to aid and promote the progression of the primary morbidity. We show here that chronic morphine, gut microbial dysbiosis, disruption of cholesterol/bile acid metabolism and gut inflammation; have a linear correlation. This opens up the prospect of devising minimally invasive adjunct treatment strategies involving microbiome and bile acid modulation and thus bringing down morphine-mediated inflammation in the host.
Project description:Interactions among neuroglial and vascular components are crucial for retinal angiogenesis and blood-retinal barrier (BRB) maturation. Neuronal synaptic dysfunctions precede vascular abnormalities in many retinal pathologies. However, whether neuronal activity, specifically glutamatergic activity, regulates retinal angiogenesis and BRB maturation remains unclear. Using in vivo genetic studies in mice, single-cell RNA-sequencing and functional validation, we found that deep plexus angiogenesis and paracellular BRB maturation are delayed in Vglut1-/- retinas, where neurons fail to release glutamate. In contrast, deep plexus angiogenesis and paracellular BRB maturation are accelerated in Gnat1-/- retinas, where constitutively depolarized rods release excess glutamate. Mechanistically, Norrin expression and endothelial Norrin/b-catenin signaling are downregulated in Vglut1-/- retinas, and upregulated in Gnat1-/- retinas. Pharmacological activation of endothelial Norrin/ b-catenin signaling in Vglut1-/- retinas rescued both deep plexus angiogenesis and paracellular BRB integrity. Thus, our findings demonstrate that glutamatergic neuronal activity regulates retinal angiogenesis and BRB maturation by modulating Norrin/b-catenin signaling.
Project description:The cervical epithelium undergoes continuous changes in proliferation, differentiation and function that is critical before pregnancy to ensure fertility and during pregnancy to provide a physical and immunoprotective barrier for pregnancy maintenance. Barrier disruption can lead to the ascension of pathogens that elicit inflammatory responses and preterm birth. Here we identify epithelial subtypes in the cervix of nonpregnant, pregnant and laboring mice using single cell- transcriptome and spatial analysis. We identify heterogeneous subpopulations of epithelia displaying spatial and temporal specificity in cell proliferation, turnover and transcriptional programs. Further we identify untimely proliferation and function of epithelial cells in a model of cervical epithelial barrier disruption. Together these data provide insights as to how the cervical epithelium undergoes a continuous remodeling to maintain a dynamically shifting state of homeostasis in pregnancy and labor and provide a framework by which to understand perturbations in epithelial cell health and host-microbe interactions that contribute to risk of premature birth.
Project description:Keratinocytes respond to environmental signals by eliciting induction of genes that preserve skin’s integrity. Here we show that the transcriptional response to stress signaling is supported by short-lived epigenetic changes. Comparison of chromatin accessibility and transcriptional changes induced by barrier disruption or by loss of the nucleosome remodeler Mi-2β identified their striking convergence in mouse and human keratinocytes. Mi-2β directly repressed genes induced by barrier disruption by restricting AP1-enriched promoter-distal sites, occupied by Mi-2β and JUNB at steady state and by c-JUN after Mi-2β depletion or stress signaling. Barrier disruption led to a modest reduction in Mi-2β expression and a further selective reduction of Mi-2β localization at stress response genes possibly through competition with activated c-JUN. Consistent with a repressive role at stress response genes, genetic ablation of Mi-2β did not prevent re-establishment of barrier integrity but was required for return to homeostasis. Thus a competition between Mi-2β repressive and activating AP1 complexes may permit rapid transcriptional response to and resolution from stress signaling.
Project description:Uveitis is characterised by breakdown of the blood-retinal barrier (BRB), allowing infiltration of immune cells that mediate intraocular inflammation, which can lead to irreversible damage of the neuroretina and the loss of sight. Treatment of uveitis relies heavily on corticosteroids and systemic immunosuppression due to limited understanding of the molecular immune interactions that underpin ocular immune homeostasis. By performing single-cell transcriptomic analysis of whole dissociated mouse retinas with experimental autoimmune uveitis (EAU) versus healthy control, we gained an unbiased appreciation of the immune interactions that drive retinal inflammation in a model of posterior uveitis.
Project description:Angiogenesis, the growth of new blood vessels from pre-existing vasculature, is essential for the development of new organ systems, but transcriptional control of angiogenesis remains incompletely understood. Here we report that FOXC1 is essential for retinal angiogenesis. Endothelial cell (EC)-specific loss of Foxc1 impairs retinal vascular growth and expression of Slc3a2 and Slc7a5, which encode the heterodimeric CD98 (LAT1/4F2hc) amino acid transporter and regulate the intracellular transport of essential amino acids and activation of the mammalian target of rapamycin (mTOR). EC-Foxc1 deficiency diminishes mTOR activity, while administration of the mTOR agonist MHY-1485 rescues perturbed retinal angiogenesis. EC-Foxc1 expression is required for retinal revascularization and resolution of neovascular tufts in a model of oxygen-induced retinopathy. Foxc1 is also indispensable for pericytes, a critical component of the blood-retina barrier during retinal angiogenesis. Our findings establish FOXC1 as a crucial regulator of retinal vessels and identify therapeutic targets for treating retinal vascular disease.