title: Reactive oxygen species are involved in insulin-dependent regulation of autophagy in primary rat podocytes.
abstract: Autophagy is an intracellular defense mechanism responsible for the turnover of damaged or non-functional cellular constituents. This process provides cells with energy and essential compounds under unfavorable environmental conditions-such as oxidative stress and hyperglycemia, which are both observed in diabetes. The most common diabetes complication is diabetic nephropathy (DN), which can lead to renal failure. This condition often includes impaired podocyte function. Here we investigated autophagic activity in rat podocytes cultured with a high insulin concentration (300nM). Autophagy was activated after 60min of insulin stimulation. Moreover, this effect was abolished following pharmacological (apocynin) or genetic (siRNA) inhibition of NAD(P)H oxidase activity, indicating that insulin-dependent autophagy stimulation involved reactive oxygen species (ROS). We also observed a continuous and time-dependent increase of podocyte albumin permeability in response to insulin, and this process was slightly improved by autophagy inhibition following short-term insulin exposure. Our results suggest that insulin may be a factor affecting the development of diabetic nephropathy.
authors.affiliation: Mossakowski Medical Research Centre, Polish Academy of Sciences, Department of Molecular and Cellular Nephrology, Gdańsk, Poland. Electronic address: iaudzeyenka@imdik.pan.pl.
authors.forename: Irena
authors.initials: I
authors.lastname: Audzeyenka
authors.affiliation: Mossakowski Medical Research Centre, Polish Academy of Sciences, Department of Molecular and Cellular Nephrology, Gdańsk, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Rogacka
authors.affiliation: Mossakowski Medical Research Centre, Polish Academy of Sciences, Department of Molecular and Cellular Nephrology, Gdańsk, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Piwkowska
authors.affiliation: Laboratory of Virus Molecular Biology, Intercollegiate Faculty of Biotechnology, University of Gdańsk-Medical University of Gdańsk, Poland.
authors.forename: Michal
authors.initials: M
authors.lastname: Rychlowski
authors.affiliation: Department of Pathology, Children's Memorial Health Institute, Warsaw, Poland.
authors.forename: Joanna Beata
authors.initials: JB
authors.lastname: Bierla
authors.affiliation: Department of Pathology, Children's Memorial Health Institute, Warsaw, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Czarnowska
authors.affiliation: Mossakowski Medical Research Centre, Polish Academy of Sciences, Department of Molecular and Cellular Nephrology, Gdańsk, Poland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Angielski
authors.affiliation: Mossakowski Medical Research Centre, Polish Academy of Sciences, Department of Molecular and Cellular Nephrology, Gdańsk, Poland; Medical University of Gdańsk, Department of Clinical Chemistry, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Jankowski
mesh_terms: D000098:Acetophenones / Q000494:pharmacology; D000418:Albumins / Q000378:metabolism; D000818:Animals; D001343:Autophagy / Q000187:drug effects*; D000071192:Autophagy-Related Protein 12 / Q000378:metabolism; D000071187:Autophagy-Related Protein 5 / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D055785:Gene Knockdown Techniques; D007328:Insulin / Q000494:pharmacology*; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases / Q000172:deficiency / Q000235:genetics; D010539:Permeability / Q000187:drug effects; D050199:Podocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D000098:Acetophenones; D000418:Albumins; D000071192:Autophagy-Related Protein 12; D000071187:Autophagy-Related Protein 5; D007328:Insulin; D008869:Microtubule-Associated Proteins; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases; D017382:Reactive Oxygen Species; C526109:Anxa3 protein, rat; C056165:acetovanillone; C498911:Nox4 protein, rat
keywords: Autophagy; Filtration barrier permeability; Insulin; Podocyte; Reactive oxygen species