Kidneys of Alb/TGF-beta1 Transgenic Mice Are Deficient in Retinoic Acid and Exogenous Retinoic Acid Shows Dose-dependent Toxicity
Overview
Nephrology
Authors
Affiliations
Background: Alb/TGF-beta(1) transgenic mice overexpress active transforming growth factor-beta(1) (TGF-beta(1)) in the liver, leading to increased circulating levels of the cytokine and progressive renal fibrosis. This study was designed to explore if exogenous all-trans retinoic acid (tRA) prevents renal fibrosis in this animal model.
Methods: The retinoid profile in kidney and liver of wild-type and Alb/TGF-beta(1) transgenic mice was examined by high-performance liquid chromatography and slow-release pellets containing different amounts of tRA were implanted subcutaneously to treat the Alb/TGF-beta(1) transgenic mice, starting at 1 week of age; mice were sacrificed 2 weeks later.
Results: Kidneys of 3-week-old wild-type mice had abundant tRA, which was completely absent in kidneys of the transgenic mice. Low doses of tRA (6-10.7 mg/kg/day) failed to affect renal fibrosis although it tended to suppress the mRNA expression of some molecular markers of fibrosis and retinal dehydrogenase 2 (RALDH2), a gene encoding a key tRA-synthesising enzyme. These tendencies disappeared, mortality tended to increase and RALDH2 and connective tissue growth factor (CTGF) mRNAs significantly increased in the medium-dose group (12.7-18.8 mg/kg/day). High doses (20.1-27.4 mg/kg/day) showed even higher toxicity with increased renal fibrosis and significant mortality.
Conclusions: Alb/TGF-beta(1) transgenic mice are characterised by depletion of endogenous renal tRA. Exogenous tRA dose-dependently increases mortality and kidney fibrosis, which is associated with dose-dependent regulation of renal RALDH2 and CTGF mRNA expression.
Dysregulated Retinoic Acid Signaling in the Pathogenesis of Pseudoexfoliation Syndrome.
Zenkel M, Hoja U, Giessl A, Berner D, Hohberger B, Weller J Int J Mol Sci. 2022; 23(11).
PMID: 35682657 PMC: 9180992. DOI: 10.3390/ijms23115977.
Juin S, Pushpakumar S, Sen U Biomolecules. 2021; 11(10).
PMID: 34680110 PMC: 8533431. DOI: 10.3390/biom11101477.
Induction of retinol dehydrogenase 9 expression in podocytes attenuates kidney injury.
Li X, Dai Y, Chuang P, He J J Am Soc Nephrol. 2014; 25(9):1933-41.
PMID: 24652806 PMC: 4147989. DOI: 10.1681/ASN.2013111150.
An in vitro model for the pro-fibrotic effects of retinoids: mechanisms of action.
Rankin A, Hendry B, Corcoran J, Xu Q Br J Pharmacol. 2013; 170(6):1177-89.
PMID: 23992207 PMC: 3838693. DOI: 10.1111/bph.12348.
Zhou T, Drummen G, Qin Y Int J Mol Sci. 2013; 14(1):226-43.
PMID: 23344030 PMC: 3565260. DOI: 10.3390/ijms14010226.