renal/urinary system
albuminuria
(
J:343202
)
• mice show a 2-fold increase in albuminuria at 6 weeks of age and an 8.5-fold increase at 24 weeks of age
|
• the number of CD44+ parietal epithelial cells (PECs) lying on the Bowmans capsule increase progressively with age
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• podocyte injury (desmin staining and podocyte apoptosis) is seen as early as 6-10 weeks of age
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• progressive reduction in podocin and synaptopodin expression and eventually in podocyte number
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• focal glomerular sclerosis that worsens over time
• 18-week-old and 24-week-old mice show scarring involving 15% and about 25% of the glomeruli, respectively
• severity of scarring worsens progressively within individual glomeruli
• cuboidal CD44+ and Ki-67+ cells are seen in the tubules of older (18-week-old) mice
• however, macrophage infiltration and expression of CCL2 and TNF-alpha are unaltered within glomeruli and no IgM, C3, IgG, and IgA staining is seen indicating no inflammation
|
renal cast
(
J:343202
)
• cast formation is seen in tubules
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• glomeruli show an early and progressive reduction in both mtDNA copy number and expression of mitochondrial transcription factor/genes
• glomeruli mitochondrial membrane potential undergoes progressive reduction and mitochondrial oxidative stress is enhanced
• however, glomeruli show normal mitochondrial structure and mitochondrial mass is not altered
• however, no changes in mitochondrial membrane potential and TFAM expression are seen in renal tubular epithelial cells
• cells positive for both the PEC marker annexin A3 and CD44 are seen in the glomerular tuft indicating activated PECs
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• 6-week-old podocytes show increased apoptosis
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• tunneling nanotube-mediated mitochondrial transfer is almost abolished in mutant podocytes
• study of mitochondrial bioenergetics shows that basal and maximal oxygen consumption rate, ATP-linked respiration, and reserve capacity are reduced in podocytes, most likely due to alterations in oxidative phosphorylation as nonmitochondrial respiration and proton leak are unaltered
• low reserve capacity indicates that mitochondria function at their maximal capacity and are unable to meet any additional ATP demand
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• older mice exhibit a 40% reduction in creatinine clearance
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homeostasis/metabolism
albuminuria
(
J:343202
)
• mice show a 2-fold increase in albuminuria at 6 weeks of age and an 8.5-fold increase at 24 weeks of age
|
• mice show an early and progressive increase in N-acetyl-beta-D-glucosaminidase activity
|
cellular
• 6-week-old podocytes show increased apoptosis
|
Mouse Models of Human Disease |
DO ID | OMIM ID(s) | Ref(s) | |
focal segmental glomerulosclerosis | DOID:1312 |
OMIM:PS603278 |
J:343202 |