Inhibition of p66ShcA longevity gene rescues podocytes from HIV-1-induced oxidative stress and apoptosis.
Glomerular visceral epithelial cells (podocytes) play a critical role in the pathogenesis of human immunodeficiency virus (HIV)-associated nephropathy. A key question concerns the mechanism(s) by which the HIV-1 genome alters the phenotype of the highly specialized, terminally differentiated podocytes. Here, using an in vitro system of conditionally immortalized differentiated human podocytes (CIDHPs), we document a pivotal role for the p66ShcA protein in HIV-1-induced reactive oxygen species generation and CIDHP apoptosis. CIDHP transfected with truncated HIV-1 construct (NL4-3) exhibit increased reactive oxygen species metabolism, DNA strand breaks, and a 5-fold increase in apoptosis, whereas the opposite was true for NL4-3/CIDHP co-transfected with mu-36p66ShcA (micro-36) dominant negative expression vector or isoform-specific p66-small interfering RNA. Phosphorylation at Ser-36 of the wild type p66ShcA protein, required for p66ShcA redox function and inhibition of the potent stress response regulator Foxo3a, was unchanged in micro-36/NL4-3/CIDHP but increased in NL4-3/CIDHP. Acute knockdown of Foxo3a by small interfering RNA induced a 50% increase in micro-36/NL4-3/CIDHP apoptosis, indicating that Foxo3a-dependent responses promote the survival phenotype in micro-36 cells. We conclude that inhibition of p66ShcA redox activity prevents generation of HIV-1 stress signals and activation of the CIDHP apoptosis program.
Husain
Mohammad
M
From the Department of Medicine, Division of Kidney Diseases and Hypertension, North Shore Long Island Jewish Health System, New Hyde Park, New York 11040.
Meggs
Leonard G
LG
Department of Medicine, Division of Nephrology and Hypertension, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07103.
Vashistha
Himanshu
H
Department of Medicine, Division of Nephrology and Hypertension, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07103.
Simoes
Sonia
S
Department of Medicine, Division of Nephrology and Hypertension, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07103.
Griffiths
Kevin O
KO
Department of Medicine, Division of Nephrology and Hypertension, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07103.
Kumar
Dileep
D
From the Department of Medicine, Division of Kidney Diseases and Hypertension, North Shore Long Island Jewish Health System, New Hyde Park, New York 11040.
Mikulak
Joanna
J
From the Department of Medicine, Division of Kidney Diseases and Hypertension, North Shore Long Island Jewish Health System, New Hyde Park, New York 11040.
Mathieson
Peter W
PW
Children's Renal Unit, University of Bristol, Bristol, BS1 5NB United Kingdom.
Saleem
Moin A
MA
Children's Renal Unit, University of Bristol, Bristol, BS1 5NB United Kingdom.
Del Valle
Luis
L
Department of Neuroscience, Temple University, School of Medicine, Philadelphia, Pennsylvania 19122.
Pina-Oviedo
Sergio
S
Department of Neuroscience, Temple University, School of Medicine, Philadelphia, Pennsylvania 19122.
Wang
Jin Ying
JY
Department of Neuroscience, Temple University, School of Medicine, Philadelphia, Pennsylvania 19122.
Seshan
Surya V
SV
Department of Surgical Pathology, Weil Cornell Medical School, New York, New York 10065.
Malhotra
Ashwani
A
Department of Medicine, Division of Nephrology and Hypertension, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07103.
Reiss
Krzysztof
K
Department of Neuroscience, Temple University, School of Medicine, Philadelphia, Pennsylvania 19122.
Singhal
Pravin C
PC
From the Department of Medicine, Division of Kidney Diseases and Hypertension, North Shore Long Island Jewish Health System, New Hyde Park, New York 11040. Electronic address: singhal@lij.edu.
D021581:Active Transport, Cell Nucleus / Q000502:physiology; D017209:Apoptosis / Q000502:physiology*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D015816:Cell Adhesion Molecules, Neuronal; D002461:Cell Line, Transformed; D000071316:Forkhead Box Protein O3; D051858:Forkhead Transcription Factors / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics; D015658:HIV Infections / Q000378:metabolism / Q000473:pathology*; D015497:HIV-1; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology*; D010641:Phenotype; D010766:Phosphorylation / Q000502:physiology; D050199:Podocytes / Q000166:cytology / Q000378:metabolism / Q000821:virology; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species / Q000378:metabolism; D055765:Shc Signaling Adaptor Proteins / Q000235:genetics* / Q000378:metabolism; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D013912:Threonine / Q000378:metabolism; D014162:Transfection
D002352:Carrier Proteins; D015816:Cell Adhesion Molecules, Neuronal; C499517:FOXO3 protein, human; D000071316:Forkhead Box Protein O3; D051858:Forkhead Transcription Factors; D008565:Membrane Proteins; C430845:NLGN4X protein, human; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; C528024:SHC1 protein, human; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D049452:Green Fluorescent Proteins; D013912:Threonine