scholarly journals Decrease in transient receptor potential melastatin 6 mRNA stability caused by rapamycin in renal tubular epithelial cells

2011 ◽  
Vol 1808 (6) ◽  
pp. 1502-1508 ◽  
Author(s):  
Akira Ikari ◽  
Ayumi Sanada ◽  
Hayato Sawada ◽  
Chiaki Okude ◽  
Chie Tonegawa ◽  
...  
Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1893
Author(s):  
Chieko Hirota ◽  
Yui Takashina ◽  
Yuta Yoshino ◽  
Hajime Hasegawa ◽  
Ema Okamoto ◽  
...  

Background: A low level of serum magnesium ion (Mg2+) is associated with type 2 diabetes mellitus (T2D). However, the molecular mechanism of Mg2+ deficiency has not been fully clarified. The current study sought to assesses the effect of reactive oxygen species on the expression of Mg2+ channels and miRNA. Methods: The expression of Mg2+ channels and miRNA were examined by real-time polymerase chain reaction. Intracellular Mg2+ concentration was measured by Magnesium Green fluorescence measurement. Results: The mRNA level of transient receptor potential melastatin 6 (TRPM6), which functions as Mg2+ influx channel in the distal convoluted tubule (DCT) of the kidney, was decreased by glycated albumin (GA), but not by insulin in rat renal tubule-derived NRK-52E cells. The mRNA levels of TRPM7, a homologue of TRPM6, and CNNM2, a Mg2+ efflux transporter located at the basolateral membrane of DCT, were changed by neither GA nor insulin. The generation of reactive oxygen species (ROS) was increased by GA. Hydrogen peroxide (H2O2) dose-dependently decreased TRPM6 mRNA, but it inversely increased the reporter activity of TRPM6. H2O2 accelerated the degradation of TRPM6 mRNA in actinomycin D assay without affecting TRPM7 and CNNM2 mRNA expressions. Nine miRNAs were considered as candidates for the regulator of stability of TRPM6 mRNA. Among them, miR-24-3p expression was increased by H2O2. The H2O2-induced reduction of TRPM6 mRNA was rescued by miR-24-3p siRNA. Magnesium Green fluorescence measurement showed that Mg2+ influx is suppressed by H2O2, which was rescued by an antioxidant and miR-24-3p siRNA. Conclusions: We suggest that GA decreases TRPM6 expression mediated by the elevation of ROS and miR-24-3p in renal tubular epithelial cells of T2D.


2021 ◽  
Vol 12 (8) ◽  
Author(s):  
Ying Ding ◽  
Dao-yang Zhou ◽  
Hong Yu ◽  
Tao Zhu ◽  
Feng Guo ◽  
...  

AbstractAlthough increasing evidence has confirmed that the apoptosis of renal tubular epithelial cells (RTECs) is a crucial contributor to the onset and development of septic acute kidney injury (AKI), the pathological mechanism by which RTEC apoptosis is upregulated during septic AKI is not entirely clear. In this study, a rat model of septic AKI was induced by a cecal ligation puncture procedure or lipopolysaccharide (LPS) injection. Four differentially expressed long noncoding RNAs (DE-Lncs) in the rat model of septic AKI were determined using RNA-sequencing and verified by qRT-PCR. Among the four DE-Lncs, the expression level of lncRNA NONRATG019935.2 (9935) exhibited the most significant reduction in both septic AKI rats and LPS-treated NRK-52E cells (a rat RTEC line). The overexpression of 9935 suppressed cell apoptosis and p53 protein level in LPS-treated NRK-52E cells, and retarded septic AKI development in the rat model of septic AKI. Mechanistically, 9935 decreased the human antigen R (HuR)-mediated Tp53 mRNA stability by limiting the combination of HuR and the 3′UTR region of Tp53 mRNA in RTECs. The overexpression of HuR abrogated the inhibitory effect of pcDNA-9935 on the LPS-induced apoptosis of NRK-52E and rat primary RTECs. In conclusion, 9935 exerts its role in septic AKI by suppressing the p53-mediated apoptosis of RTECs, and this essential role of 9935 relies on its destructive effect on HuR-mediated Tp53 mRNA stability.


Author(s):  
Ahsen Ustaoglu ◽  
Akinari Sawada ◽  
Chung Lee ◽  
Wei-Yi Lei ◽  
Chien-Lin Chen ◽  
...  

The underlying causes of heartburn, characteristic symptom of gastro-esophageal reflux disease(GERD), remain incompletely understood. Superficial afferent innervation of the esophageal mucosa in nonerosive reflux disease(NERD) may drive nociceptive reflux perception, but its acid-sensing role has not yet been established. Transient receptor potential vanilloid subfamily member-1(TRPV1), transient receptor potential Melastatin 8(TRPM8), and acid sensing ion channel 3(ASIC3) are regulators of sensory nerve activity and could be important reflux-sensing receptors within the esophageal mucosa. We characterised TRPV1, TRPM8, and ASIC3 expression in esophageal mucosa of GERD patients. We studied 10 NERD, 10 erosive reflux disease(ERD), 7 functional heartburn(FH), and 8 Barrett's esophagus(BE) patients. Biopsies obtained from the distal esophageal mucosa were co-stained with TRPV1, TRPM8, or ASIC3, and CGRP, CD45, or E-cadherin. RNA expression of TRPV1, TRPM8, and ASIC3 was assessed using qPCR. NERD patients had significantly increased expression of TRPV1 on superficial sensory nerves compared to ERD (p=0.028) or BE (p=0.017). Deep intrapapillary nerve endings did not express TRPV1 in all phenotypes studied. ASIC3 was exclusively expressed on epithelial cells most significantly in NERD and ERD patients (p=<0.0001). TRPM8 was expressed on submucosal CD45+ leukocytes. Superficial localisation of TRPV1-immunoreactive nerves in NERD, and increased ASIC3 co-expression on epithelial cells in NERD and ERD suggests a mechanism for heartburn sensation. Esophageal epithelial cells may play a sensory role in acid reflux perception and act interdependently with TRPV1-expressing mucosal nerves to augment hypersensitivity in NERD patients, raising the enticing possibility of topical antagonists for these ion channels as a therapeutic option.


Sign in / Sign up

Export Citation Format

Share Document