scholarly journals FOXO1 Overexpression Attenuates Tubulointerstitial Fibrosis and Apoptosis in Diabetic Kidneys by Ameliorating Oxidative Injury via TXNIP-TRX

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Linlin Ji ◽  
Qingzhu Wang ◽  
Fengjuan Huang ◽  
Tingting An ◽  
Feng Guo ◽  
...  
Keyword(s):  
Renal Function ◽  
High Glucose ◽  
Cell Injury ◽  
Tubulointerstitial Fibrosis ◽  
Ros Generation ◽  
Proximal Tubular ◽  
Renal Proximal Tubular

Objective. The generation of hyperglycemia-induced reactive oxygen species (ROS) is a key event in diabetic nephropathy (DN) development. Since forkhead box class O1 (FOXO1) is associated with oxidative stress and shows a positive effect on DN, its role on renal function and the underlying mechanism is still unclear. Methods. We examined the role of FOXO1 in vivo (in a transgenic diabetic mouse model overexpressing Foxo1) and in vitro (in human HK-2 cells with FOXO1 knockin (KI) and knockout (KO) cultured under high glucose). Results. Renal proximal tubular cells of kidney biopsies from patients with DN showed tubulointerstitial fibrosis and apoptosis. Accordingly, these proximal tubular injuries were accompanied by the increase of ROS generation in diabetic mice. Tissue-specific Foxo1 overexpression in transgenic mice had a protective effect on the renal function and partially reversed tubular injuries by attenuating the diabetes-induced increase in TXNIP and decrease in the TRX levels. FOXO1 knockin and knockout HK-2 cells were constructed to identify the associations between FoxO1 and TXNIP-TRX using CRISPR/CAS9. Similarly, the effects of FOXO1 KI and KO under high glucose were significantly modulated by the treatment of TRX inhibitor PX-12 and TXNIP small interfering RNA. In addition, TXNIP and TXN were identified as the direct FOXO1 transcriptional targets by chromatin immunoprecipitation. Conclusion. The regulatory role of FOXO1/TXNIP-TRX activation in DN can protect against the high glucose-induced renal proximal tubular cell injury by attenuating cellular ROS production. Modulating the FOXO1/TXNIP-TRX pathway may be a new therapeutic target in DN.

scholarly journals Atrasentan increased the expression of klotho by mediating miR-199b-5p and prevented renal tubular injury in diabetic nephropathy

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Wen-Ling Kang ◽  
Gao-Si Xu
Keyword(s):  
Diabetic Nephropathy ◽  
High Glucose ◽  
Tubular Injury ◽  
Mice Model ◽  
Renal Tubular Cells ◽  
Proximal Tubular ◽  
Renal Proximal Tubular ◽  
Renal Tubular

Abstract Atrasentan is a promising therapy for treating diabetic nephropathy (DN). Here we evaluated whether atrasentan down-regulated the miR-199b-5p expression, thereby increasing klotho and preventing renal tubular injury in DN. One-hundred patients with type 2 diabetes mellitus (T2DM) and 40 healthy subjects were included. A DN mice model was established by an injection of streptozotocin (STZ). Human renal proximal tubular epithelial HK-2 cells were exposed to high glucose (20 mmol/L). Treated the mice and HK-2 cells with atrasentan and we then investigated whether and how miR-199b-5p and Klotho were involved in preventing renal tubular injury in DN. In patients, the serum miR-199b-5p level increased and the klotho concentration decreased in accordance with elevated albuminuria. Atrasentan down-regulated miR-199b-5p and up-regulated klotho of the DN mice and HK-2 cells exposed to high glucose. High glucose promoted the binding of histone H3 to the miR-199b-5p promoter and atrasentan canceled this effect. MiR-199b-5p targeted the 3′ UTR of klotho. Overexpression of miR-199b-5p canceled the effects of atrasentan on klotho expression and apoptosis of renal tubular cells in both in vivo and in vitro. The increased serum klotho, mediated by miR-199b-5p, is a possible mechanism by which atrasentan prevents renal tubular injury in DN.

scholarly journals A75 ROLE OF LRRK2 IN INFLAMMATORY BOWEL DISEASE

2018 ◽  
Vol 1 (suppl_2) ◽  
pp. 118-118
Author(s):  
J Rocha ◽  
C Sun ◽  
M Glogauer ◽  
D Philpott
Keyword(s):  
Listeria Monocytogenes ◽  
Myeloid Cell ◽  
Mucosal Barrier ◽  
Ros Generation ◽  
Transwell Assay ◽  
Bacteria Growth ◽  
Tlr4 Ligand

Abstract Background Variants of the leucine-rich repeat kinase 2 (LRRK2) are associated with an increased susceptibility to Parkinson disease but also Crohn’s disease (CD). Aims The present research is designed to develop a comprehensive understanding of the role of LRRK2 in immune system modulation, and how dysfunction of this pathway may lead to the development of CD. Methods WT and LRRK2-deficient neutrophil were infected with Gram-positive Bacteria (Listeria monocytogenes-LM) in a gentamicin protection assays and colony-forming unit assessment will determine the competence of LRRK2 deficient cells for bacterial phagocytosis as well as killing capacity). To examine how LRRK2 is involved in the generation of ROS during the respiratory burst, we will first examine if neutrophil from LRRK2-KO mice have altered ROS generation upon infection with LM and addition of PMA. We evaluate in vitro the ability of neutrophils from LRRK2-KO versus WT mice to transmigrate in vitro in a transwell assay using fMLP as a chemattractant. Also, we investigate the peritoneal cells (by FACS analysis) after injection of different microbial stimuli including FK105 (NOD1 ligand), MDP (NOD2 ligand) and LPS (TLR4 ligand) and anti-cd3 model of ielitis. Results We found that LRRK2 KO mice have a defect in migration of neutrophils to the peritoneal cavity after injection of different microbial stimuli including FK10565 (NOD1 ligand), MDP (NOD2 ligand) and LPS (TLR4 ligand). Neutrophils from LRRK2 mice were compromised in their ability to transmigrate in vitro in a transwell assay using fMLP as a chemoattractant. Chemotaxis was also compromised. In parallel, we designed experiments to examine reactive oxygen species (ROS) produced in response to infection of myeloid cells with bacteria. Neutrophils from LRRK2 KO mice infected with Listeria monocytogenes were less able to restrict bacteria growth compared to WT cells. Consistent with these findings, cells from LRRK2 KO mice produced lower levels of ROS following bacterial infection. In order to determine whether myeloid cell migration is compromised in vivo during inflammation, we performed experiments in WT and KO mice looking at different models of ileitis/colitis. Conclusions With this work we will further characterize the role of LRRK2 in intestinal homeostasis and mucosal barrier maintenance, including how its deficiency may predispose an individual to developing CD. Funding Agencies CAG, CIHR

In Vitro and In Vivo Evaluation of Amphiphilic Chitosan Derivatives for Inhibition of Organic Cation Transport Function

2020 ◽  
Vol 859 ◽  
pp. 45-50
Author(s):  
Sirima Soodvilai ◽  
Sunhapas Soodvila ◽  
Warayuth Sajomsang ◽  
Theerasak Rojanarata ◽  
Prasopchai Patrojanasophon ◽  
...  
Keyword(s):  
Organic Cation ◽  
Drug Disposition ◽  
Organic Cation Transporter ◽  
Transport Function ◽  
Chitosan Derivatives ◽  
Proximal Tubular Epithelial Cells ◽  
Proximal Tubular ◽  
Renal Proximal Tubular

This study explored the interaction of amphiphilic chitosan derivatives, N-benzyl-N,O-succinyl chitosan (BSCS), N-naphthyl-N,O-succinyl chitosan (NSCS) and N-octyl-N,O-succinyl chitosan (OSCS), with renal organic cation transporter 2 (OCT2). The influence of amphiphilic chitosan derivatives on renal OCT2 transport function was determined by monitoring the transport of a positively charged substrate into human renal proximal tubular epithelial cells (RPTEC/TERT1 cells), and murine kidney. Amphiphilic chitosan derivatives inhibited 3H-MPP (a substrate of OCT2) transport in the renal cells in a concentration-reliance characteristic. OSCS reduced the accumulation of the cationic drug, cisplatin, in RPTEC/TERT1 cells. This effect was more pronounced than that of other chitosan derivatives. In addition, co-administration of cisplatin and OSCS significantly reduced cisplatin accumulation compared with receiving cisplatin alone. This result was accompanied by the decrease in nephrotoxicity induced by cisplatin. In conclusion, OSCS inhibited OCT2 function and reduced cationic drug disposition in human renal proximal tubular cells and murine kidney.

scholarly journals Tetrahydrocurcumin Ameliorates Diabetic Cardiomyopathy by Attenuating High Glucose-Induced Oxidative Stress and Fibrosis via Activating the SIRT1 Pathway

2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Kaifeng Li ◽  
Mengen Zhai ◽  
Liqing Jiang ◽  
Fan Song ◽  
Bin Zhang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Signaling Pathway ◽  
Diabetic Cardiomyopathy ◽  
High Glucose ◽  
Therapeutic Potential ◽  
Ros Generation ◽  
Protective Effects ◽  
Collagen Iii

Hyperglycemia-induced oxidative stress and fibrosis play a crucial role in the development of diabetic cardiomyopathy (DCM). Tetrahydrocurcumin (THC), a major bioactive metabolite of natural antioxidant curcumin, is reported to exert even more effective antioxidative and superior antifibrotic properties as well as anti-inflammatory and antidiabetic abilities. This study was designed to investigate the potential protective effects of THC on experimental DCM and its underlying mechanisms, pointing to the role of high glucose-induced oxidative stress and interrelated fibrosis. In STZ-induced diabetic mice, oral administration of THC (120 mg/kg/d) for 12 weeks significantly improved the cardiac function and ameliorated myocardial fibrosis and cardiac hypertrophy, accompanied by reduced reactive oxygen species (ROS) generation. Mechanically, THC administration remarkably increased the expression of the SIRT1 signaling pathway both in vitro and in vivo, further evidenced by decreased downstream molecule Ac-SOD2 and enhanced deacetylated production SOD2, which finally strengthened antioxidative stress capacity proven by repaired activities of SOD and GSH-Px and reduced MDA production. Additionally, THC treatment accomplished its antifibrotic effect by depressing the ROS-induced TGFβ1/Smad3 signaling pathway followed by reduced expression of cardiac fibrotic markers α-SMA, collagen I, and collagen III. Collectively, these finds demonstrated the therapeutic potential of THC treatment to alleviate DCM mainly by attenuating hyperglycemia-induced oxidative stress and fibrosis via activating the SIRT1 pathway.

scholarly journals Antioxidant Therapy in Graves’ Orbitopathy

2020 ◽  
Vol 11 ◽  
Author(s):  
Giulia Lanzolla ◽  
Claudio Marcocci ◽  
Michele Marinò
Keyword(s):  
Ros Generation ◽  
Related Condition ◽  
Orbital Radiotherapy ◽  
Antioxidant Agents ◽  
Graves Orbitopathy ◽  
High Doses

The balance of the cell redox state is a key point for the maintenance of cellular homeostasis. Increased reactive oxygen species (ROS) generation leads to oxidative damage of tissues, which is involved in the development of several diseases, including autoimmune diseases. Graves’ Orbitopathy (GO) is a disfiguring autoimmune-related condition associated with Graves’ Disease (GD). Patients with active, moderate-to-severe GO, are generally treated with high doses intravenous glucocorticoids (ivGCs) and/or orbital radiotherapy. On the contrary, up to recently, local ointments were the treatment most frequently offered to patients with mild GO, because the risks related to ivGCs does not justify the relatively poor benefits expected in mild GO. However, a medical treatment for these patients is heavily wanted, considering that GO can progress into more severe forms and also patients with mild GO complain with an impairment in their quality of life. Thus, based on the role of oxidative stress in the pathogenesis of GO, a therapy with antioxidant agents has been proposed and a number of studies have been performed, both in vitro and in vivo, which is reviewed here.

scholarly journals Renoprotective Effects of Nobiletin on High Glucose-Induced Loss of Proximal Tubular Microvilli

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 412-412
Author(s):  
Min kyung Kang ◽  
Dongyeon Kim ◽  
Young-Hee Kang
Keyword(s):  
Proximal Tubule ◽  
High Glucose ◽  
Citrus Fruit ◽  
Cellular Polarity ◽  
Funding Sources ◽  
In Vivo Animal Model ◽  
Proximal Tubular Epithelial Cells ◽  
Proximal Tubular ◽  
Renal Proximal Tubular

Abstract Objectives Kidney proximal tubular epithelium has microvillar brush borders, which is critical to renal reabsorption. Hyperglycemia induce change the loss of brush border and cellular polarity, tight junction disruption. Nobiletin is a polymethoxyflavone present in citrus fruit and peels, and has anti-inflammatory effects. This study investigated the renoprotective effects of nobiletin on proximal tubule microvillar ultrastructure and reabsorption under diabetic condition. Methods Human renal proximal tubular epithelial cells (RPTEC) were incubated in a media exposed to 33 mM glucose in the absence and presence of 1–20 μM nobiletin up to 6 days. Antibodies F-actin, villin, cubulin, megalin, SGLT2 and GLUT2 were used for Western blot analysis. The in vivo animal model employed db/db mice orally administrated with 10 mg/kg of nobiletin. Extracts of tissues were subjected to Western blotting or immunohistochemical staining. Results High glucose declined expression of F-actin and villin required for the assembly of proximal tubule microvilli. In addition, the expression of glucose uptake proteins of GLUT2 and SGLT2 was prompted in hyperglycemia. However, nontoxic nobiletin enhanced the expression of F-actin reduced by high glucose, while the elevated expression of the GLUT2 and SGLT2 was attenuated by nobiletin. In the in vivo study, oral administration of 10 mg/kg nobiletin inhibited loss of tubular microvilli through restoring expression of F-actin and villin in diabetic kidneys. Furthermore, nobiletin reduced expressions of GLUT2 and the albumin uptake receptors of cubulin and megalin in db/db mouse kidneys. Conclusions These results demonstrated that nobiletin curtailed loss of the proximal tubular microvillar proteins responsible for tubular reabsorption. Nobiletin may be a potent renoprotective agent counteracting diabetes-associated proximal tubular dysfunctions leading to kidney failure. Funding Sources This work was supported by the National Research Foundation of Korea (NRF) grants funded by the Korea government (2017R1A6A3A04011473).

scholarly journals No Cytotoxic and Inflammatory Effects of Empagliflozin and Dapagliflozin on Primary Renal Proximal Tubular Epithelial Cells under Diabetic Conditions In Vitro

2020 ◽  
Vol 21 (2) ◽  
pp. 391 ◽  
Author(s):  
Patrick C. Baer ◽  
Benjamin Koch ◽  
Janina Freitag ◽  
Ralf Schubert ◽  
Helmut Geiger
Keyword(s):  
Epithelial Cells ◽  
Cell Injury ◽  
Cellular Damage ◽  
Tubular Epithelial Cells ◽  
Urinary Glucose ◽  
Proximal Tubular Epithelial Cells ◽  
Proximal Tubular ◽  
Vitro Model ◽  
Renal Proximal Tubular

Gliflozins are inhibitors of the renal proximal tubular sodium-glucose co-transporter-2 (SGLT-2), that inhibit reabsorption of urinary glucose and they are able to reduce hyperglycemia in patients with type 2 diabetes. A renoprotective function of gliflozins has been proven in diabetic nephropathy, but harmful side effects on the kidney have also been described. In the current project, primary highly purified human renal proximal tubular epithelial cells (PTCs) have been shown to express functional SGLT-2, and were used as an in vitro model to study possible cellular damage induced by two therapeutically used gliflozins: empagliflozin and dapagliflozin. Cell viability, proliferation, and cytotoxicity assays revealed that neither empagliflozin nor dapagliflozin induce effects in PTCs cultured in a hyperglycemic environment, or in co-medication with ramipril or hydro-chloro-thiazide. Oxidative stress was significantly lowered by dapagliflozin but not by empagliflozin. No effect of either inhibitor could be detected on mRNA and protein expression of the pro-inflammatory cytokine interleukin-6 and the renal injury markers KIM-1 and NGAL. In conclusion, empa- and dapagliflozin in therapeutic concentrations were shown to induce no direct cell injury in cultured primary renal PTCs in hyperglycemic conditions.

scholarly journals Reactive oxygen species blockade and action of insulin on expression of angiotensinogen gene in proximal tubular cells

2004 ◽  
Vol 183 (3) ◽  
pp. 535-550 ◽  
Author(s):  
Tusty-Jiuan Hsieh ◽  
Pierre Fustier ◽  
Chih-Chang Wei ◽  
Shao-Ling Zhang ◽  
Janos G Filep ◽  
...  
Keyword(s):  
High Glucose ◽  
Diabetic Rat ◽  
Ros Generation ◽  
Ang Ii ◽  
Proximal Tubular Cells ◽  
Tubular Cells ◽  
Gf 109203X ◽  
Proximal Tubular ◽  
Renal Proximal Tubular Cells ◽  
Renal Proximal Tubular

We reported previously that insulin inhibits the stimulatory effect of high glucose on the expression of angiotensinogen (ANG) gene in both rat immortalized renal proximal tubular cells (IRPTCs) and non-diabetic rat renal proximal tubular cells (RPTCs), but has no effect in diabetic rat RPTCs. In the present study we investigated whether hyperglycaemia-induced resistance to the insulin-induced inhibition of expression of the ANG gene is mediated via the generation of reactive oxygen species (ROS) in RPTCs. Rat IRPTCs were cultured for 2 weeks in high-glucose (25 mM) or normal-glucose (5 mM) medium plus angiotensin II (Ang II) with or without a superoxide scavenger (tiron), or inhibitors of: NADPH oxidase (diphenylene iodinium, DPI), Ang II type 1 and 2 receptors (losartan and PD123319), angiotensin-converting enzyme (perindopril), protein kinase C (GF 109203X), or glutamine:fructose-6-phosphate amino-transferase (azaserine). Cellular generation of ROS, and ANG and renin mRNA levels were assessed by lucigenin assay and specific reverse transcriptase-PCR respectively. Phosphorylation of p44/42 mitogen-activated protein kinase (p44/42 MAPK) was evaluated by western blotting. Prolonged exposure of IRPTCs to high concentrations of glucose or Ang II evoked generation of ROS and resistance to the insulin-induced inhibition of expression of the ANG gene and of p44/42 MAPK phosphorylation. Co-incubation of IRPTCs with tiron, DPI, losartan, PD123319, perindopril, GF 109203X or azaserine prevented ROS generation, restoring the inhibitory action of insulin on ANG gene expression and on p44/42 MAPK phosphorylation. In conclusion, our studies demonstrate that blockade of both ROS generation and activation of the intrarenal renin–angiotensin system improves the inhibitory action of insulin on ANG gene expression in IRPTCs in conditions of high glucose.

scholarly journals CircRNA-DAPK1 promotes vascular cell pyroptosis in diabetes by regulating the circ-DAPK1/miR-4454/TXNIP axis.

2021 ◽  
Author(s):  
Tianchi Chen ◽  
Xiangtao Zheng ◽  
Yangyan He ◽  
Chenyang Qiu ◽  
Xiaohui Wang ◽  
...  
Keyword(s):  
High Glucose ◽  
Luciferase Reporter ◽  
Glucose Medium ◽  
Vascular Cell ◽  
Normal Medium ◽  
High Glucose Medium ◽  
Signaling Axis

Abstract Background Circular RNAs have been demonstrated to play an important role in the development of vascular diseases. However, little is known about the role of circ-021774, also named circ-DAPK1, in vascular cell pyroptosis. Methods Circ-DAPK1 was selected from circular RNA sequencing data of HUVECs treated with high glucose medium and normal medium. RT-qPCR was used to determine the expression of circ-DAPK1 in vivo and in vitro. Dual luciferase reporter assay, fluorescence in situ hybridization (FISH) and RNA immunoprecipitation (RIP) were performed to prove the interaction of circ-DAPK1, miRNA-4454 and thioredoxin-interactingprotein (TXNIP). Adeno-associated virus (AAV) was injected intravenously to establish mouse models. PI staining, western-blot and transmission electron microscopy (TEM) analyses were performed to identify the role of circ-DAPK1 in promoting pyroptosis. Results We found that circ-DAPK1 was highly expressed in high glucose medium cultured HUVECs and db/db mice. In vitro and in vivo experiments demonstrated that circ-DAPK1 knockdown decreased the number of PI+ cells, the expression of ASC, NLRP3, GSDMD-N, cleaved caspase-1, IL-18 and IL-1β. In a mechanistic study, the circ-DAPK1/miRNA-4454/TXNIP signaling axis was demonstrated to promote vascular cell pyroptosis in diabetes. Conclusions Circ-DAPK1 functions as a promoter of vascular cell pyroptosis in diabetes via the circ-DAPK1/miRNA-4454/TXNIP signaling axis.

Sign in / Sign up

Export Citation Format

Share Document