Two critical defensive functions of the outer epidermis, the permeability barrier and antimicrobial defense, share certain structural and biochemical features. Moreover, three antimicrobial peptides (AMPs), i.e., mouse β-defensin 3 (mBD3), mouse cathelicidin antimicrobial peptide (mCAMP), and the neuroendocrine peptide, catestatin (Cst), all localize to the outer epidermis, and both mBD3 and mC...

Cigarette smoking is associated with various cutaneous disorders with defective permeability. Yet, whether cigarette smoking influences epidermal permeability barrier function is largely unknown. Here, we measured skin biophysical properties, including permeability barrier homeostasis, stratum corneum (SC) integrity, SC hydration, skin surface pH, and skin melanin/erythema index, in cigarette s...

The fluorescein kinetics in the vitreous was simulated with a computer to consider several factors such as permeability of the blood-retinal barrier, outward active transport, plasma fluorescein dynamics, diffusion of fluorescein in the vitreous, and fluorescein leakage from the blood-aqueous barrier. Kinetic vitreous fluorophotometry was performed in normal individuals to estimate the inward a...

Intestinal epithelial barrier defects, or increased paracellular permeability, were first reported in patients with Crohn's disease (CD) over 25 years ago. Although increased permeability may herald relapse to active disease, suggesting that impaired barrier function may contribute to progression, limited understanding of the mechanisms that create barrier defects in CD has made it impossible t...

Existence of a selective nucleocytoplasmic permeability barrier is attributed to Phenylalanine-Glycine rich proteins (FG-nups) within the central channel of the nuclear pore complex (NPC). Limited understanding of the FG-nup structural arrangement hinders development of strategies directed at disrupting the NPC permeability barrier. In this report we explore an alternative approach to enhancing...

Tight junctions between intestinal epithelial cells mediate the permeability of the intestinal barrier, and loss of intestinal barrier function mediated by TNF signaling is associated with the inflammatory pathophysiology observed in Crohn's disease and celiac disease. Thus, factors that modulate intestinal epithelial cell response to TNF may be critical for the maintenance of barrier function....

The role of changes in blood-brain barrier permeability in the pathogenesis of hepatic encephalopathy remains uncertain. To test the hypothesis that brain microvessel permeability is nonselectively increased in hepatic encephalopathy we measured the blood-brain barrier permeability-surface area product in rats with acute liver failure induced by intraperitoneal injection of galactosamine. The p...

We previously reported decreases in blood-brain barrier permeability in the ovine fetus at 80% of gestation after antenatal corticosteroids and shown that permeability is not reduced in newborn lambs after postnatal corticosteroids. We now test the hypotheses that exogenous antenatal corticosteroids decrease blood-brain barrier permeability at 60% but not 90% of gestation in ovine fetuses and t...

Endothelial cells that make up brain capillaries and constitute the blood-brain barrier become different from peripheral endothelial cells in response to inductive factors found in the nervous system . We have established a cell culture model of the bloodbrain barrier by treating brain endothelial cells with a combination of astrocyte-conditioned medium and agents that elevate intracellular cAM...

Data are accumulating that emphasize the important role of the intestinal barrier and intestinal permeability for health and disease. However, these terms are poorly defined, their assessment is a matter of debate, and their clinical significance is not clearly established. In the present review, current knowledge on mucosal barrier and its role in disease prevention and therapy is summarized. ...