Normal Proteasome Function Is Needed to Prevent Kidney Graft Injury during Cold Storage Followed by Transplantation

Kidney transplantation is the preferred treatment for end-stage kidney disease (ESKD). However, there is a shortage of transplantable kidneys, and donor organs can be damaged by necessary cold storage (CS). Although CS improves the viability of kidneys from deceased donors, prolonged CS negatively affects transplantation outcomes. Previously, we reported that renal proteasome function decreased after rat kidneys underwent CS followed by transplantation (CS + Tx). Here, we investigated the mechanism underlying proteasome dysfunction and the role of the proteasome in kidney graft outcome using a rat model of CS + Tx. We found that the key proteasome subunits β5, α3, and Rpt6 are modified, and proteasome assembly is impaired. Specifically, we detected the modification and aggregation of Rpt6 after CS + Tx, and Rpt6 modification was reversed when renal extracts were treated with protein phosphatases. CS + Tx kidneys also displayed increased levels of nitrotyrosine, an indicator of peroxynitrite (a reactive oxygen species, ROS), compared to sham. Because the Rpt6 subunit appeared to aggregate, we investigated the effect of CS + Tx-mediated ROS (peroxynitrite) generation on renal proteasome assembly and function. We treated NRK cells with exogenous peroxynitrite and evaluated PAC1 (proteasome assembly chaperone), Rpt6, and β5. Peroxynitrite induced a dose-dependent decrease in PAC1 and β5, but Rpt6 was not affected (protein level or modification). Finally, serum creatinine increased when we inhibited the proteasome in transplanted donor rat kidneys (without CS), recapitulating the effects of CS + Tx. These findings underscore the effects of CS + Tx on renal proteasome subunit dysregulation and also highlight the significance of proteasome activity in maintaining graft function following CS + Tx.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:25

Enthalten in:

International journal of molecular sciences - 25(2024), 4 vom: 10. Feb.

Sprache:

Englisch

Beteiligte Personen:

Bhattarai, Dinesh [VerfasserIn]
Lee, Seong-Ok [VerfasserIn]
MacMillan-Crow, Lee Ann [VerfasserIn]
Parajuli, Nirmala [VerfasserIn]

Links:

Volltext

Themen:

14691-52-2
Bortezomib
Cold storage and transplantation
EC 3.4.25.1
Journal Article
Peroxynitrous Acid
Proteasome Endopeptidase Complex
Proteasome assembly chaperone PAC1
Proteasome dysfunction
Proteasome subunits Rpt6 and B5
Reactive Oxygen Species

Anmerkungen:

Date Completed 26.02.2024

Date Revised 27.02.2024

published: Electronic

Citation Status MEDLINE

doi:

10.3390/ijms25042147

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM368868133