Abstract: FR-PO234

APOL1 Provides Podocyte Protection against Apoptosis through Down Regulation of MicroRNA (miR)193a in Adverse Milieus

Session Information

Category: Cell Biology

  • 202 Apoptosis, Proliferation, Autophagy, Cell Senescence, Cell Transformation

Authors

  • Kumar, Vinod, Feinstein Institute for Medical Research, Great Neck, New York, United States
  • Lan, Xiqian, Feinstein Institute for Medical Research, Great Neck, New York, United States
  • Aslam, Rukhsana, Feinstein Institute for medical research, Glenoaks, New York, United States
  • Hussain, Ali, Feinstein Institute of Medical Research, New York, New York, United States
  • Marashi Shoshtari, Seyedeh Shadafarin, The Feinstein Institute for Medical Research, Manhasset, New York, United States
  • Meyer-Schwesinger, Catherine, University of Hamburg, Hamburg, Germany
  • Malhotra, Ashwani, Feinstein Institute for Medical Research, Great Neck, New York, United States
  • Skorecki, Karl, Rambam Health Care Campus, Haifa, Israel
  • Singhal, Pravin C., Feinstein Institute for Medical Research, Great Neck, New York, United States
Background

Adverse milieus such as high glucose and puromycin aminonucleoside (PAN) have been reported to induce podocyte (PD) injury both in vitro and in vivo studies. APOL1, expressed intracellularly is a minor component of circulating lipid-rich trypanolytic multiprotein complexes in certain primate species including humans. Genetic epidemiologic studies suggest that humans carrying APOL1 wild-type (G0) are less likely to develop chronic kidney disease when compared to humans carrying APOL1 risk alleles (APOL1G1 and G2). We hypothesize that PD expression of APOL1G0 provides protection against apoptosis in adverse milieus.

Methods

Human podocytes (PDs) were transduced with either vector (PDV) or APOL1G0 (wild- type, PDG0). PDVs and PDG0 were treated with different concentrations of glucose (5, 15, 30, and 35 mM) or PAN (0, 5, 10, 25, 50, and 100 nM) for 48 hours (n=4); in other set of experiments, PDs were incubated in media containing either buffer, high glucose (30 mM), PAN (50 nM) with or without interferon-γ (IFN-γ; 20 nM, an APOL1 inducer) for 48 hours (n=4); PDV were incubated in media containing, high glucose (30 mM) , PAN (50 nM), with or without miR193a inhibitor (25 nM) for 48 hours (n=4). At the end of incubation periods, cells were evaluated for reactive oxygen species (ROS) generation and apoptosis. Proteins and RNAs were extracted from cells treated under similar conditions. Protein blots were probed for APOL1, and caspase-3; RNAs were assayed for miR193a.

Results

PDVs displayed higher generation of ROS and a greater number of apoptotic cells when compared to PDG0, both in high glucose and PAN milieus. PDG0 displayed enhanced expression of APOL1 but decreased miR193a levels when compared to PDVs. Both high glucose and PAN treated PDs displayed enhanced expression of caspase-3. IFN-γ increased APOL1 expression in PDs and attenuated induction of apoptosis as well as caspase-3 expression, both in high glucose and PAN milieus. MicroRNA193a inhibitor decreased miR193a levels, increased APOL1 expression and attenuated apoptosis, both in high glucose and PAN milieus.

Conclusion

APOL1G0 provides protection against apoptosis in adverse milieus through down regulation of miR193.

Funding

  • NIDDK Support