Dataset Information

Streptozotocin induces renal proximal tubular injury through p53 signaling activation

ABSTRACT: Streptozotocin (STZ) is an anti-cancer drug that is primarily used to treat neuroendocrine tumors (NETs) in clinical settings and develop type 1 diabetes rodent models in experimental fields. STZ is incorporated into cells through the glucose transporter, GLUT2, which is primarily expressed in pancreatic β-cells or proximal tubular epithelial cells in the kidney. However, its cytotoxic effects on kidney cells have been underestimated and the underlying mechanisms remain unclear. We herein demonstrated that DNA damage and subsequent p53 signaling were responsible for the development of STZ-induced tubular epithelial injury. We detected tubular epithelial DNA damage in NET patients treated with STZ. Unbiased transcriptomics of tubular epithelial cells in vitro showed the activation of the p53 signaling pathway by STZ. STZ induced DNA damage and activated p53 signaling in vivo in a dose-dependent manner, resulting in reduced membrane transport. The localization of STZ-induced kidney injury was limited to within the kidney cortex, which was independent of blood glucose. The pharmacological inhibition of p53 and sodium-glucose transporter 2 (SGLT2) mitigated STZ-induced epithelial injury. However, the cytotoxic effects of STZ on pancreatic β-cells were preserved in SGLT2 inhibitor-treated mice. The present results demonstrate the strong proximal tubular-specific cytotoxicity of STZ and the underlying mechanisms in vivo, which may be ameliorated by a SGLT2 inhibitor pretreatment. Since the cytotoxic effects of STZ against β-cells were not impaired by dapagliflozin, a pretreatment with a SGLT2 inhibitor has potential as a preventative remedy for kidney injury in NET patients treated with STZ.

ORGANISM(S): Rattus norvegicus

PROVIDER: GSE215337 | GEO | 2023/06/07

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Purpose:Renal injury with the loss of podocyte was characteristic pathology of diabetic nephropathy (DN) and correlated with increased albuminuria. Many studies have found the nephroprotective effect of the novel inhibitors of sodium-glucose cotransporter 2 (SGLT2-is), like Dapagliflozin, delaying the progression of DN. However, the underlying mechanisms of SGLT2 associated with podocyte injury are still not fully elucidated. Methods: Through mRNA sequencing, streptozotocin-induced and Dapagliflozin-intraperitoneal injection mice models were established to explore potential mechanism between Dapagliflozin and renal phenotype. And all changes referring this observed pathway were proven repeatedly in podocyte. Results: Here, we generated the streptozotocin-induced DN models and found the accumulation of nephrotoxin and pathological lesions of the kidney, including interstitial inflammatory infiltration, mesangial expansion and glomerular sclerosis, while low expression of SGLT2 mitigated these injuries in Dapagliflozin-treated mice. Moreover, mRNA expression profile in these treated models determined the significance of insulin-like growth factor-1 receptor (IGF1R)/PI3K regulatory axis in glomerular injury. Particularly, SGLT2-is inhibited the increase of mesenchymal marker, α-SMA and the decrease of podocyte marker, nephrin at the gene or protein level. KEGG analysis also showed the enrichment of phosphatidylinositol signaling system and TGF-β/smad pathway. In parallel, the protein level of IGF1R, phosphorylated PI3K, and α-SMA were increased in high-glucose stimulated human podocyte, and reduced in Dapagliflozin (50nM and 100nM) or OSI-906 (inhibitor of IGF1R, 60nM) used groups. Notably, combination of the two inhibitors produced an accumulative effect in the protection of podocyte integrity. Mechanistically, IGF1 or IGF2 could bind to IGF1 receptors to mediate the epithelial-mesenchymal transition (EMT) of diabetic podocyte in response to the upregulation of SGLT2. Indeed, we enrolled the urine and plasma samples from a cohort consisting of 13 healthy people, and a cohort of 19 patients with DN using SGLT2-inhibitors (n=9) or not (n=10). Compared with pure DN patients, Elisa results suggested an increased circulation and excretion level of IGF1/2 in SGLT2-is used DN cohort. Conclusions: Taken together, our study reported the key role of SGLT2/IGF1R/PI3K signaling in regulating podocyte EMT. Modulating the IGF1R expression may provide a novel idea for DN therapy.

Project description:Clinical use of a major cancer chemotherapeutic agent, cisplatin, is restricted to dose-limiting renal toxicity. A transcriptomic approach enabled us to extract putative molecules including Pleckstrin homology-like domain, family A, member-3 (Phlda3) contributing to the renal injury. This study investigated the expression of Phlda3 and its regulatory role in tubular injury induced by cisplatin in vivo and in vitro. Real-time PCR and immunoblot assays confirmed that Phlda3 was highly up-regulated in the kidney of mice after a single dose of cisplatin treatment, which preceded increases in the blood urea nitrogen or serum creatinine levels. Particularly, the level of Phlda3 transcript was substantially increased at an early time than that of kidney injury molecule-1, and remained elevated. The effect of cisplatin or acetaminophen treatment on Phlda3 expression in the liver was minimal. Consistently, treatment of NRK52E, a renal tubular cell line, with cisplatin caused increases in Phlda3 mRNA and protein. Knockdown of Phlda3 reversed the decrease in cell viability by cisplatin, supporting the role of Phlda3 in cell death. Akt phosphorylation initially increased after cisplatin treatment, but decreased thereafter. Cisplatin treatment elicited p53 accumulation via mdm2 repression, inducing its target genes, p21 and cyclin G1. Phlda3 deficiency attenuated a decrease in Akt phosphorylation by cisplatin, and prevented p53 accumulation, supporting the role of Phlda3 for p53-mediated tubular cell death. Other renal toxicants, cyclosporine A and CdCl2, also enhanced Phlda3-dependent cell death. Overall, nephrotoxicants including cisplatin induce Phlda3, which leads to p53-mediated tubular cell death via mdm2 repression caused by Akt inhibition. Since the datasets reported on the effect of cisplatin on the kidney were obtained from animals treated with multiple and relatively high doses of cisplatin, we did our cDNA array analyses day 3 after a single dose of cisplatin administration to mice (i.p., 15 mg/kg) and compared the profiles of kidney microarray data. The transcriptomic approach enabled us to find the putative genes encoding molecules contributing to renal injury. Among those genes represented on the microarray, 33 genes were found to be differentially expressed by cisplatin treatment when a 2-fold change cutoff was used. The regulation of exemplary mRNAs identified in the array analysis was confirmed by qRT-PCR. C57BL/6 mice (9 weeks old) were intraperitoneally injected with a single dose of cisplatin (15 mg/kg body weight) or vehicle (saline). The cDNA microarray experiments were done for the kidney of mice 3 days after treatment. Each group contained 3 males.

Project description:Gene expression profiling of kidneys from the murine model of HIV-associated nephropathy (HIVAN) identified an association between the expression of an endoplasmic reticulum (ER)-associated protein reticulon-1, RTN1, and the severity of kidney disease. Of the three known RTN1 isoforms, only RTN1A protein expression was increased in kidneys of murine models of HIVAN, diabetic nephropathy (DN), and renal fibrosis and humans with HIVAN and DN. Both mRNA and protein expression of RTN1-A in the kidneys correlated inversely with estimated glomerular filtration rate (eGFR) in patients with DN. In kidney cells, RTN1 overexpression induced ER stress/apoptosis, whereas RTN1 knockdown attenuated tunicamycin-, and hyperglycemia-induced ER stress/apoptosis. Incubation of kidney cells with high glucose media induced RTN1A expression likely through oxidative pathway, while knockdown of RTN1A inhibited high glucose-induced apoptosis. RTN1A interacts with PERK and mutation of its N- or C-terminal domain abolished its effects on ER stress/apoptosis. In vivo, knockdown of Rtn1a expression either before or after kidney injury attenuated renal fibrosis in mice with unilateral ureteral obstruction (UUO) and tubular epithelial cell-specific knockdown of Rtn1a also ameliorated ER stress and renal fibrosis in the UUO mice. Finally, knockdown of Rtn1a also attenuated proteinuria, glomerular hypertrophy, and mesangial expansion in STZ-induced diabetic mice, which were associated with suppression of ER stress markers. Taken together, these data suggest that RTN1 is a mediator of kidney disease progression that exacerbates kidney injury through ER stress and apoptosis. Animal studies: All animal studies were approved by the IACUC committee of Mount Sinai School of Medicine. HIV-1 transgenic mice, Tg26, and their littermates were generated and genotyped as described. Only male heterozygous Tg26 in the FVB/N background were used in the study, because homozygous HIV-transgenic mice are not viable for more than few weeks postnatally. UUO and folic acid-induced nephropathy models were created as described . Mice were grouped as wild type, Tg26 with mild kidney injury, Tg26, with serious kidney injury. The kidneys were collected from these mice for histology, western blot, real-time PCR analysis, and microarray studies. Kidney disease was confirmed by measurement of proteinuria, renal function, and histologic analysis. Microarray studies: Affymetrix gene expression microarrays were performed at the Mount Sinai Institution Microarray Core Facility. The Affymetrix GeneChip® Mouse Genome 430 2.0 Array was used to profile gene expression in the kidney cortex of Tg26 and WT mice 37. One-way analysis of variance test (ANOVA) was applied to the dataset to identify the genes that were differentially expressed between the two groups. P-values were corrected using Benjamini–Hochberg false discovery rate (FDR) with a threshold of 0.05.

Dataset Information

Streptozotocin induces renal proximal tubular injury through p53 signaling activation

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure