| 1. |
- Legouis, D., et al.
(författare)
-
Altered proximal tubular cell glucose metabolism during acute kidney injury is associated with mortality
- 2020
-
Ingår i: Nature Metabolism. - : Springer Science and Business Media LLC. - 2522-5812. ; 2:8
-
Tidskriftsartikel (refereegranskat)abstract
- Acute kidney injury (AKI) is strongly associated with mortality, independently of its cause. The kidney contributes to up to 40% of systemic glucose production by gluconeogenesis during fasting and under stress conditions. Whether kidney gluconeogenesis is impaired during AKI and how this might influence systemic metabolism remain unknown. Here we show that glucose production and lactate clearance are impaired during human and experimental AKI by using renal arteriovenous catheterization in patients, lactate tolerance testing in mice and glucose isotope labelling in rats. Single-cell transcriptomics reveal that gluconeogenesis is impaired in proximal tubule cells during AKI. In a retrospective cohort of critically ill patients, we demonstrate that altered glucose metabolism during AKI is a major determinant of systemic glucose and lactate levels and is strongly associated with mortality. Thiamine supplementation increases lactate clearance without modifying renal function in mice with AKI, enhances glucose production by renal tubular cells ex vivo and is associated with reduced mortality and improvement of the metabolic pattern in a retrospective cohort of critically ill patients with AKI. This study highlights an unappreciated systemic role of renal glucose and lactate metabolism under stress conditions, delineates general mechanisms of AKI-associated mortality and introduces a potential intervention targeting metabolism for a highly prevalent clinical condition with limited therapeutic options.
|
|
| 2. |
|
|
| 3. |
- Bustamante, M, et al.
(författare)
-
Insulin potentiates AVP-induced AQP2 expression in cultured renal collecting duct principal cells
- 2005
-
Ingår i: American journal of physiology. Renal physiology. - : American Physiological Society. - 1931-857X .- 1522-1466. ; 288:2, s. F334-F344
-
Tidskriftsartikel (refereegranskat)abstract
- In the renal collecting duct (CD), water reabsorption depends on the presence of aquaporin-2 (AQP2) in the apical membrane of principal cells. AQP2 expression and subcellular repartition are under the control of AVP. Some pieces of experimental evidence indicate that additional hormonal factors, including insulin, may also control AQP2 expression and thereby CD water permeability. We have previously shown that AVP induces endogenous AQP2 expression in cultured mouse mpkCCDcl4CD principal cells ( 23 ). In the present study, we investigated the effect of insulin on AQP2 expression in mpkCCDcl4cells. Addition of insulin to the basal medium of cells grown on filters slightly increased AQP2 mRNA and protein expression, whereas insulin potentiated the effect of AVP. The potentiation of AVP-induced AQP2 expression by insulin was abolished by actinomycin D, a transcriptional inhibitor. Analysis of AQP2 protein expression under conditions of AVP washout and/or in the presence of chloroquine, a lysosomal degradation inhibitor, revealed that insulin did not significantly alter AQP2 protein degradation. Inhibition of ERK, p38 kinase, and phosphatidylinositol 3′-kinase (PI 3-kinase) activities prevented the insulin-induced stimulation of AQP2 expression, whereas inhibition of PKC has no effect. Taken together, our results indicate that insulin increased AQP2 protein expression mostly through increased AQP2 mRNA levels in cultured mpkCCDcl4cells. This effect most likely relies on increased AQP2 gene transcription in response to MAPK and PI 3-kinase activation.
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
