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- Mitrofanova, A, et al.
(författare)
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SMPDL3b modulates insulin receptor signaling in diabetic kidney disease
- 2019
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1, s. 2692-
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Tidskriftsartikel (refereegranskat)abstract
- Sphingomyelin phosphodiesterase acid-like 3b (SMPDL3b) is a lipid raft enzyme that regulates plasma membrane (PM) fluidity. Here we report that SMPDL3b excess, as observed in podocytes in diabetic kidney disease (DKD), impairs insulin receptor isoform B-dependent pro-survival insulin signaling by interfering with insulin receptor isoforms binding to caveolin-1 in the PM. SMPDL3b excess affects the production of active sphingolipids resulting in decreased ceramide-1-phosphate (C1P) content as observed in human podocytes in vitro and in kidney cortexes of diabetic db/db mice in vivo. Podocyte-specific Smpdl3b deficiency in db/db mice is sufficient to restore kidney cortex C1P content and to protect from DKD. Exogenous administration of C1P restores IR signaling in vitro and prevents established DKD progression in vivo. Taken together, we identify SMPDL3b as a modulator of insulin signaling and demonstrate that supplementation with exogenous C1P may represent a lipid therapeutic strategy to treat diabetic complications such as DKD.
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| 2. |
- Persson, Patrik, et al.
(författare)
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Adenosine A(2)a receptor stimulation prevents proteinuria in diabetic rats by promoting an anti-inflammatory phenotype without affecting oxidative stress
- 2015
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Ingår i: Acta Physiologica. - : Wiley: 12 months. - 1748-1708 .- 1748-1716. ; 214:3, s. 311-318
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Tidskriftsartikel (refereegranskat)abstract
- AimDiabetic patients are at increased risk for kidney disease. There is presently no clinical treatment available that effectively protects kidney function in diabetics. This study investigates whether chronic stimulation of the adenosine A(2a) receptor (A(2a)AR) protects kidney function in insulinopenic diabetic rats. MethodsStreptozotocin-induced diabetic rats and corresponding controls were chronically treated with the adenosine A(2a)AR agonist CGS21680 throughout the four-week diabetes duration. Kidney function was thereafter investigated, and urine and plasma samples were collected for analysis of protein, oxidative stress and inflammatory markers. ResultsGlomerular filtration rate, renal blood flow, filtration fraction and diabetes-induced kidney hypoxia were all unaffected by chronic A(2a)AR stimulation. Furthermore, diabetic rats had increased oxidative stress, which was further increased by chronic A(2a)AR stimulation. However, the 10-fold increased urinary protein excretion observed in the diabetic rats was completely prevented by chronic A(2a)AR stimulation. These beneficial effects were accompanied by reduced levels of the pro-inflammatory TNF- and increased levels of the anti-inflammatory IL-10 as well as decreased infiltration of macrophages, glomerular damage and basement membrane thickness. ConclusionChronic A(2a)AR stimulation prevents proteinuria and glomerular damage in experimental diabetes via an anti-inflammatory mechanism independent of oxidative stress and kidney hypoxia.
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