The role of mitogen-activated protein kinases (MAPK) in the mechanism of EGF-mediated prevention of acetaldehyde-induced tight junction disruption was evaluated in Caco-2 cell monolayers. Pretreatment of cell monolayers with EGF attenuated acetaldehyde-induced decrease in resistance and increase in inulin permeability and redistribution of occludin, zona occludens-1 (ZO-1), E-cadherin, and β-ca...

Occludin has been identified from chick liver as a novel integral membrane protein localizing at tight junctions (Furuse, M., T. Hirase, M. Itoh, A. Nagafuchi, S. Yonemura, Sa. Tsukita, and Sh. Tsukita. 1993. J. Cell Biol. 123:1777-1788). To analyze and modulate the functions of tight junctions, it would be advantageous to know the mammalian homologues of occludin and their genes. Here we descr...

HIV-1 transactivator protein (Tat) has been shown to play an important role in HIV-associated neurocognitive disorders. The aim of the present study was to evaluate the relationship between occludin and amyloid-beta (Aβ) transfer receptors in human cerebral microvascular endothelial cells (hCMEC/D3) in the context of HIV-1-related pathology. The protein expressions of occludin, receptor for adv...

Occludin is a tetraspan integral membrane protein in epithelial and endothelial tight junction (TJ) structures that is projected to have two extracellular loops. We have used peptides emulating central regions of human occludin's first and second loops, termed O-A:101-121 and O-B:210-228, respectively, to examine potential molecular interactions between these two regions of occludin and other T...

Brain microvascular endothelial cells (BMECs) are the primary component of the blood-brain barrier (BBB). Tight junction (TJ) proteins, including claudin, occludin and zonula occludens (ZO)-1, ZO-2 and ZO-3, maintain the structural integrity of BMECs. Ethanol activates the assembly and disassembly of TJs, which is a process that is regulated by protein kinase C (PKC). In addition, ethanol treat...

BACKGROUND Tight junctions (TJs) are mainly composed of claudins, occludin, and tight junction adhesion molecules (JAM). The invasive and metastatic phenotype of highly invasive cancer cells has been related to abnormal structure and function of TJs, and with expression of activated matrix metalloproteinases (MMPs). The relevance of these mechanisms responsible for the invasion and metastasis o...

T he lining of the small intestine locks out bacteria and toxins while soaking up nutrients and water. By observing intestinal cells of live mice through the microscope, Marchiando et al. (1) reveal the mechanism that regulates this barrier. The study shows the importance of the tight junction protein occludin for the process and identifi es the endocytic route that removes occludin to adjust p...

Objective. This study aimed to determine the influence of Tang Wang One Decoction (TWOD) on the retinal vessels of diabetic rats. Methods. The hemorheology of diabetic rats was observed. Morphological studies of retinal vessels were conducted using optical microscopy and electron microscopy. Immunological histochemistry assay was used to measure the expression levels of MMP-9, occludin, and cla...

After the simulation of anoxia by ATP depletion of MDCK cell monolayers with metabolic inhibitors, the tight junction (TJ) is known to become structurally perturbed, leading to loss of the permeability barrier. Peripheral TJ proteins such as zonula occludens 1 (ZO-1), ZO-2, and cingulin become extremely insoluble and associate into large macromolecular complexes (T. Tsukamoto and S. K. Nigam. J...

BACKGROUND In pancreaticobiliary maljunction (PBM), the sphincter of Oddi can not control bile and pancreatic juice flow, which may lead to two-way reflux of bile and pancreatic juice, thus causing chronic inflammation, thickening, fibrosis and metaplasia of the common bile duct wall. These pathophysiological changes have been linked to disruption of the epithelium barrier in the common bile du...