LAUSR.org creates dashboard-style pages of related content for over 1.5 million academic articles. Sign Up to like articles & get recommendations!

The Role of Caveolae on Albumin Passage through Glomerular Endothelial and Epithelial Cells: The New Etiology of Urinary Albumin Excretion.

Photo from wikipedia

BACKGROUND In the traditional theory of albuminuria, small amounts of albumin pass through the fenestrae in glomerular endothelial cells, then through the slit membrane in the gaps between foot processes… Click to show full abstract

BACKGROUND In the traditional theory of albuminuria, small amounts of albumin pass through the fenestrae in glomerular endothelial cells, then through the slit membrane in the gaps between foot processes of glomerular epithelial cells. In the novel theory, large amounts of albumin pass through glomerular capillaries and are taken up by megalin and cubilin receptors on tubular epithelial cells. These etiologies of urinary albumin excretion are still controversial, and the details of albumin passage through the three layers of glomerular capillaries (glomerular endothelial cells, basement membrane, and epithelial cells) have never been entirely elucidated. SUMMARY Recent advances in basic research have shown that caveolae, which are cell invaginations located on the surface of both glomerular endothelial and epithelial cells, play pivotal roles in the endocytosis, transcytosis, and exocytosis of albumin. Albumin enters into glomerular endothelial and epithelial cells through caveolae; subsequent transcytosis of albumin is not actin- or microtubule-dependent in glomerular endothelial cells, but is actin-dependent in glomerular epithelial cells. Exocytosis of albumin in glomerular endothelial cells occurs via early endosomes through a process that bypasses other endosome-associated organelles. In contrast, exocytosis of albumin in glomerular epithelial cells occurs via early endosomes through a process that results in lysosomal degradation of some albumin particles. Key Messages: This caveolae-dependent pathway may provide a new pathophysiology for albumin passage through glomerular endothelial and epithelial cells, leading to a new etiology for urinary albumin excretion that connects both traditional and novel theories of albuminuria.

Keywords: endothelial epithelial; glomerular endothelial; epithelial cells; etiology; urinary albumin

Journal Title: Contributions to nephrology
Year Published: 2018

Link to full text (if available)


Share on Social Media:                               Sign Up to like & get
recommendations!

Related content

More Information              News              Social Media              Video              Recommended



                Click one of the above tabs to view related content.