You have accessJournal of UrologyStone Disease: Basic Research & Pathophysiology I1 Apr 2018PD03-12 SELECTIVE AUTOPHAGY VIA MTORC1 AND TFEB SIGNALS IN THE SUPPRESSION OF KIDNEY STONE FORMATION Rei Unno, Tsuyoshi Kawabata, Hiroshi Takase, Teruaki Sugino, Yutaro Tanaka, Kazumi Taguchi, Naoko Unno, Shuzo Hamamoto, Ryosuke Ando, Atsushi Okada, Kenjiro Kohri, Tamotsu Yoshimori, and Takahiro Yasui Rei UnnoRei Unno More articles by this author , Tsuyoshi KawabataTsuyoshi Kawabata More articles by this author , Hiroshi TakaseHiroshi Takase More articles by this author , Teruaki SuginoTeruaki Sugino More articles by this author , Yutaro TanakaYutaro Tanaka More articles by this author , Kazumi TaguchiKazumi Taguchi More articles by this author , Naoko UnnoNaoko Unno More articles by this author , Shuzo HamamotoShuzo Hamamoto More articles by this author , Ryosuke AndoRyosuke Ando More articles by this author , Atsushi OkadaAtsushi Okada More articles by this author , Kenjiro KohriKenjiro Kohri More articles by this author , Tamotsu YoshimoriTamotsu Yoshimori More articles by this author , and Takahiro YasuiTakahiro Yasui More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.278AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES We found that cellular damage caused by calcium oxalate (CaOx) was repaired by the induction of autophagy using renal tubule cultured cells and CaOx crystal model mice, and the failure of the repair mechanism caused kidney stones. In this study, we focused on selective autophagy and upstream regulatory factors mTORC1 and transcription factor TFEB and tried to elucidate the mechanism of calculus formation. METHODS In vitro: We exposed renal tubular cells to calcium oxalate monohydrate (COM) crystals at a concentration of 20 μg/cm2, and selective autophagy was examined by double immunostaining of organelle, ubiquitin protein, phosphorylated p62, and Western blotting of PINK1 and PARK2/Parkin. mTORC1 activity was examined by Western blotting of phosphorylated S6 kinase, and nuclear import of TFEB was examined by transfection of GFP-TFEB. In each examination, we compared autophagy knockdown cells that had a deleted atg5 gene using CRISPR-Cas9. In vivo: We used autophagy visualization (GFP-LC3) mice, and kidney crystal formation in mice was induced by daily intra-abdominal injection of 80 mg/kg-1 glyoxylic acid. We investigated selective autophagy by immunostaining of FK2, Gal3, and phosphorylated p62 and examined expression of phosphorylated S6 and TFEB by immunostaining and Western blotting. Finally, we examined the suppression effect of mTOR inhibitor, which can promote autophagy, on crystal formation. RESULTS In vitro: Organelles damaged by the crystal were labeled with poly-ubiquitin and selectively removed by autophagy. Long-term crystal exposure caused autophagy reduction due to the promotion of mTORC1 signal and inhibition of nuclear localization of TFEB. In vivo: Autophagy selectively removed injured organelle but declined due to control of upstream signal as GOX administration increased. Therefore, when mTOR inhibitor was administered at the same time as GOX, autophagy reduction and crystal formation were significantly suppressed. CONCLUSIONS Autophagy suppressed kidney crystal formation by selectively removing damaged organelles. The breakdown of the autophagy mechanism via crystal upstream signals promotes crystal formations, suggesting the possibility of developing novel therapeutic drugs targeting these signals. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e76 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Rei Unno More articles by this author Tsuyoshi Kawabata More articles by this author Hiroshi Takase More articles by this author Teruaki Sugino More articles by this author Yutaro Tanaka More articles by this author Kazumi Taguchi More articles by this author Naoko Unno More articles by this author Shuzo Hamamoto More articles by this author Ryosuke Ando More articles by this author Atsushi Okada More articles by this author Kenjiro Kohri More articles by this author Tamotsu Yoshimori More articles by this author Takahiro Yasui More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...