Tubular Mechanisms in Proteinuria



Chronic progressive nephropathies, independent of the type of initial insult, are often associated with high levels of urinary protein excretion. In addition to well established glomerular role in proteinuria, recent studies have shown that proximal tubular cell plays important role in development of proteinuria both under physiologic and pathologic conditions. Many single-site mutations and complete PTC dysfunction result in a high level of albuminuria, without any histologic or electron microscopy structural alterations in the glomerular filtration barrier. Reabsorption of filtered albumin involves a low-capacity/high-affinity megalin-cubulin receptor-mediated process and a high-capacity/low-affinity, process that could be fluid-phase endocytosis. Future studies are warranted examining proteinuria not only as a glomerular impairment but also as proximal tubule dysfunction and may lead to many new advances in the diagnosis and treatment of proteinuric states.


Kidney Proximal tubule cell Albuminuria Proteinuria 



Acute kidney injury


Activator protein 1


Bcl-2 associated death promoter


Brain abundant signal protein 1


B cell lymphoma 2


B-cell lymphoma-extra large


Bone morphogenic protein


Danger-associated molecular patterns


Diphtheria toxin


Epidermal growth factor


Epithelial-to-mesenchymal transition


Endoplasmic reticulum


Extracellular signal related kinases


Fas associated protein with death domain


Neonatal Fc receptor


Fluorescein isothiocyanate


3-hydroxy-3-methylglutaryl CoA






Dissociation constant


Kilo dalton


Mitogen activated protein


Monocyte chemoattractant protein


Major histocompatibility complex


Munich-Wistar Fromter


Nuclear factor kappa-light chain-enhancer of activated B cells


Na+/H+ exchanger isoform3


Nod like Receptor


NOD- like receptor family Pyrin domain containing 3


Opossum kidney


Platelet derived growth factor


Protein kinase B


Peroxisome proliferator activated receptor


Proximal tubule


Proximal tubular cell


Regulated on activation normal T cell expressed and secreted


Receptor associated protein


Random control trial


Tumor growth factor


Tissue inhibitors of metalloproteinases


Toll-like receptors


Uridine Tri-phosphate


α-Smooth muscle actin


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.The Roudebush VA Medical Centre, Indiana Center for Biological MicroscopyIndiana University School of MedicineIndianapolisUSA

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