Τίτλος:
Rapamycin induced ultrastructural and molecular alterations in glomerular podocytes in healthy mice
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Background. In the normal kidney, rapamycin is considered to be non-nephrotoxic. In the present study, we investigated whether rapamycin is indeed non-nephrotoxic by examining the ultrastructural and molecular alterations of podocytes in healthy mice. Methods. Balb/c mice were given three different intraperitoneal doses of rapamycin for 1 week (dose model)low-dose group: 1 mg/kg/day, intermediate-dose (ID) group: 1.5 mg/kg/day and high-dose (HD) group: 3 mg/kg/day; four mice in each group. An ID of rapamycin was also given for three different periods (time model): 1, 4 and 8 weeks; four mice were in each group. Mice treated with dimethyl sulphoxide served as controls. Body weight was measured weekly. Renal function was assessed by serum creatinine at the time of sacrifice. For estimation of albuminuria, 24-h urine collections were performed before treatment and weekly thereafter. Glomerular content of nephrin, podocin, Akt and Ser473-phospho-Akt was estimated by western blot and immunofluorescence. Nephrin and podocin messenger RNA (mRNA) were measured by real-time polymerase chain reaction. Mean podocyte foot process width (FPW) was measured by electron microscopy. Results. Urine albumin levels increased in the HD and 4-week groups. Renal function was modestly deteriorated in the HD group. The mean FPW increased in a dose-dependant manner at Week 1, further deteriorated at Week 4 and finally improved at Week 8. Nephrin and podocin mRNA levels showed a significant decrease at Week 1 and were restored at Week 4 and 8. Nephrin and podocin protein levels were reduced at Week 4 and recovered at Week 8. Ser473-phospho-Akt significantly increased in all rapamycin-treated groups. Conclusion. sRapamycin induced significant ultrastructural and molecular alterations in podocytes in association with albuminuria. These alterations happened early during treatment and they tended to improve over an 8-week treatment period. © The Author 2012. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.
Συγγραφείς:
Stylianou, K.
Petrakis, I.
Mavroeidi, V.
Stratakis, S.
Kokologiannakis, G.
Lioudaki, E.
Liotsi, C.
Kroustalakis, N.
Vardaki, E.
Stratigis, S.
Perakis, K.
Kyriazis, J.
Nakopoulou, L.
Daphnis, E.
Περιοδικό:
Nephrology Dialysis Transplantation
Λέξεις-κλειδιά:
albumin; creatinine; dimethyl sulfoxide; messenger RNA; nephrin; podocin; protein kinase B; rapamycin; serine, albuminuria; animal cell; animal experiment; animal tissue; article; body weight; cell damage; cell ultrastructure; controlled study; creatinine blood level; cytotoxicity test; disease association; dose response; drug dose comparison; drug effect; drug megadose; electron microscopy; enzyme activation; enzyme phosphorylation; female; gene; gene expression regulation; glomerulus filtration rate; immunofluorescence test; kidney function test; low drug dose; mouse; nephrin gene; nonhuman; podocin gene; podocyte; priority journal; protein analysis; protein expression; real time polymerase chain reaction; urine level; Western blotting, Animals; Creatinine; Enzyme Activation; Female; Gene Expression; Immunosuppressive Agents; Intracellular Signaling Peptides and Proteins; Kidney Transplantation; Membrane Proteins; Mice; Mice, Inbred BALB C; Microscopy, Electron, Transmission; Podocytes; Proto-Oncogene Proteins c-akt; RNA, Messenger; Sirolimus
