TY - JOUR
T1 - MYH9 E1841K mutation augments proteinuria and podocyte injury and migration
AU - Cechova, Sylvia
AU - Dong, Fan
AU - Chan, Fang
AU - Kelley, Michael J.
AU - Ruiz, Phillip
AU - Le, Thu H.
N1 - Funding Information:
This work was supported by internal funding from the Division of Nephrology, Department of Medicine, University of Virginia. The Research Histology Core at the Department of Medicine, University of Virginia, provided periodic acid-Schiff (PAS) staining of kidney tissues. The Advanced Microscopy Facility at Department of Medicine, University of Virginia, provided preparations of kidney tissue samples for electron microscopy. JEOL model JEM-1230 Transmission electron microscope, funded by National Institutes of Health grant 1S10RR021017-01, was used to take images.
PY - 2018/1
Y1 - 2018/1
N2 - Intronic variants of the MYH9 gene that encodes the nonmuscle myosin heavy chain IIA are associated with diabetic nephropathy in European Americans and with sickle cell disease–associated nephropathy. However, the causal functional variants of MYH9 have remained elusive. Rare missense mutations in MYH9 cause macrothrombocytopenia and are occasionally associated with development of nephropathy. The E1841K mutation is among the common MYH9 missense mutations and has been associated with nephropathy in some carriers. To determine the contribution of the E1841K mutation in kidney disease, we studied the effects of the E1841K mutation in mice subjected to high salt or angiotensin II (Ang II) as models of hypertension and in mice subjected to renal mass reduction as a model of CKD. Despite similar levels of BP among wild-type (MYH9+/+) mice and mice heterozygous (MYH9+/E1841K) and homozygous (MYH9E1841K/E1841K) for the mutation in each model, MYH9E1841K/E1841K mice exhibited mildly increased albuminuria in response to high salt; severe albuminuria, nephrinuria, FSGS, and podocyte foot effacement in Ang II–induced hypertension; and early mortality in the renal mass reduction model. Treatment with candesartan during Ang II–induced hypertension attenuated kidney disease development in MYH9E1841K/E1841K mice. In vitro, isolated primary podocytes from MYH9E1841K/E1841K mice exhibited increased lamellipodia formation and reorganization of F-actin stress fibers. Wound healing assays revealed that MYH9+/+ podocytes had the lowest migration rate, followed by MYH9+/E1841K then MYH9E1841K/E1841K podocytes. In conclusion, the MYH9 E1841K variant alters podocyte cytoskeletal structure and renders podocytes more susceptible to injury after a damaging stimulus.
AB - Intronic variants of the MYH9 gene that encodes the nonmuscle myosin heavy chain IIA are associated with diabetic nephropathy in European Americans and with sickle cell disease–associated nephropathy. However, the causal functional variants of MYH9 have remained elusive. Rare missense mutations in MYH9 cause macrothrombocytopenia and are occasionally associated with development of nephropathy. The E1841K mutation is among the common MYH9 missense mutations and has been associated with nephropathy in some carriers. To determine the contribution of the E1841K mutation in kidney disease, we studied the effects of the E1841K mutation in mice subjected to high salt or angiotensin II (Ang II) as models of hypertension and in mice subjected to renal mass reduction as a model of CKD. Despite similar levels of BP among wild-type (MYH9+/+) mice and mice heterozygous (MYH9+/E1841K) and homozygous (MYH9E1841K/E1841K) for the mutation in each model, MYH9E1841K/E1841K mice exhibited mildly increased albuminuria in response to high salt; severe albuminuria, nephrinuria, FSGS, and podocyte foot effacement in Ang II–induced hypertension; and early mortality in the renal mass reduction model. Treatment with candesartan during Ang II–induced hypertension attenuated kidney disease development in MYH9E1841K/E1841K mice. In vitro, isolated primary podocytes from MYH9E1841K/E1841K mice exhibited increased lamellipodia formation and reorganization of F-actin stress fibers. Wound healing assays revealed that MYH9+/+ podocytes had the lowest migration rate, followed by MYH9+/E1841K then MYH9E1841K/E1841K podocytes. In conclusion, the MYH9 E1841K variant alters podocyte cytoskeletal structure and renders podocytes more susceptible to injury after a damaging stimulus.
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U2 - 10.1681/ASN.2015060707
DO - 10.1681/ASN.2015060707
M3 - Article
C2 - 28993503
AN - SCOPUS:85040125481
VL - 29
SP - 155
EP - 167
JO - Journal of the American Society of Nephrology
JF - Journal of the American Society of Nephrology
SN - 1046-6673
IS - 1
ER -