Suppression of transient receptor potential melastatin 7 regulates pluripotency, proliferation, and differentiation of mouse embryonic stem cells via mechanistic target of rapamycin‐extracellular signal‐regulated kinase activation

Author(s):  
Wansoo Kim ◽  
Song Park ◽  
Wookbong Kwon ◽  
Daehwan Kim ◽  
Jin‐Kyu Park ◽  
...  
2015 ◽  
Vol 35 (24) ◽  
pp. 4238-4252 ◽  
Author(s):  
Matthew R. Cohen ◽  
William M. Johnson ◽  
Jennifer M. Pilat ◽  
Janna Kiselar ◽  
Alicia DeFrancesco-Lisowitz ◽  
...  

Neurite outgrowth is key to the formation of functional circuits during neuronal development. Neurotrophins, including nerve growth factor (NGF), increase neurite outgrowth in part by altering the function and expression of Ca2+-permeable cation channels. Here we report that transient receptor potential vanilloid 2 (TRPV2) is an intracellular Ca2+-permeable TRPV channel upregulated by NGF via the mitogen-activated protein kinase (MAPK) signaling pathway to augment neurite outgrowth. TRPV2 colocalized with Rab7, a late endosome protein, in addition to TrkA and activated extracellular signal-regulated kinase (ERK) in neurites, indicating that the channel is closely associated with signaling endosomes. In line with these results, we showed that TRPV2 acts as an ERK substrate and identified the motifs necessary for phosphorylation of TRPV2 by ERK. Furthermore, neurite length, TRPV2 expression, and TRPV2-mediated Ca2+signals were reduced by mutagenesis of these key ERK phosphorylation sites. Based on these findings, we identified a previously uncharacterized mechanism by which ERK controls TRPV2-mediated Ca2+signals in developing neurons and further establish TRPV2 as a critical intracellular ion channel in neuronal function.


2020 ◽  
Vol 21 (10) ◽  
pp. 985-992 ◽  
Author(s):  
Koichi Inoue ◽  
Zhi-Gang Xiong ◽  
Takatoshi Ueki

: Transient receptor potential melastatin 7 (TRPM7), along with the closely related TRPM6, are unique channels that have dual operations: cation permeability and kinase activity. In contrast to the limited tissue distribution of TRPM6, TRPM7 is widely expressed among tissues and is therefore implicated in a variety of cellular functions physiologically and pathophysiologically. The discovery of TRPM7’s unique structure imparting dual ion channel and kinase activities shed light onto novel and peculiar biological functions, such as Mg2+ homeostasis, cellular Ca2+ flickering, and even intranuclear transcriptional regulation by a cleaved kinase domain translocated to nuclei. Interestingly, at a higher level, TRPM7 participates in several biological processes in the nervous and cardiovascular systems, in which excitatory responses in neurons and cardiomyocytes are critical for their function. Here, we review the roles of TRPM7 in cells involved in the nervous and cardiovascular systems and discuss its potential as a future therapeutic target.


2020 ◽  
Vol 17 (3) ◽  
pp. 249-258 ◽  
Author(s):  
Pavan Thapak ◽  
Mahendra Bishnoi ◽  
Shyam S. Sharma

Background: Diabetes is a chronic metabolic disorder affecting the central nervous system. A growing body of evidence has depicted that high glucose level leads to the activation of the transient receptor potential melastatin 2 (TRPM2) channels. However, there are no studies targeting TRPM2 channels in diabetes-induced cognitive decline using a pharmacological approach. Objective: The present study intended to investigate the effects of 2-aminoethoxydiphenyl borate (2-APB), a TRPM2 inhibitor, in diabetes-induced cognitive impairment. Methods: Streptozotocin (STZ, 50 mg/kg, i.p.) was used to induce diabetes in rats. Animals were randomly divided into the treatment group, model group and age-matched control and pre se group. 2-APB treatment was given for three weeks to the animals. After 10 days of behavioural treatment, parameters were performed. Animals were sacrificed at 10th week of diabetic induction and the hippocampus and cortex were isolated. After that, protein and mRNA expression study was performed in the hippocampus. Acetylcholinesterase (AchE) activity was done in the cortex. Results: : Our study showed the 10th week diabetic animals developed cognitive impairment, which was evident from the behavioural parameters. Diabetic animals depicted an increase in the TRPM2 mRNA and protein expression in the hippocampus as well as increased AchE activity in the cortex. However, memory associated proteins were down-regulated, namely Ca2+/calmodulin-dependent protein kinase II (CaMKII-Thr286), glycogen synthase kinase 3 beta (GSK-3β-Ser9), cAMP response element-binding protein (CREB-Ser133), and postsynaptic density protein 95 (PSD-95). Gene expression of parvalbumin, calsequestrin and brain-derived neurotrophic factor (BDNF) were down-regulated while mRNA level of calcineurin A/ protein phosphatase 3 catalytic subunit alpha (PPP3CA) was upregulated in the hippocampus of diabetic animals. A three-week treatment with 2-APB significantly ameliorated the alteration in behavioural cognitive parameters in diabetic rats. Moreover, 2-APB also down-regulated the expression of TRPM2 mRNA and protein in the hippocampus as well as AchE activity in the cortex of diabetic animals as compared to diabetic animals. Moreover, the 2-APB treatment also upregulated the CaMKII (Thr-286), GSK-3β (Ser9), CREB (Ser133), and PSD-95 expression and mRNA levels of parvalbumin, calsequestrin, and BDNF while mRNA level of calcineurin A was down-regulated in the hippocampus of diabetic animals. Conclusion: : This study confirms the ameliorative effect of TRPM2 channel inhibitor in the diabetes- induced cognitive deficits. Inhibition of TRPM2 channels reduced the calcium associated downstream signaling and showed a neuroprotective effect of TRPM2 channels in diabetesinduced cognitive impairment.


Pancreatology ◽  
2019 ◽  
Vol 19 ◽  
pp. S94
Author(s):  
Júlia Fanczal ◽  
Petra Pallagi ◽  
Marietta Görög ◽  
Csaba Péter Bíró ◽  
Tamara Madácsy ◽  
...  

2021 ◽  
Vol 34 (1) ◽  
pp. 121-122
Author(s):  
Yi-quan Dai ◽  
Xiao-xiao Yan ◽  
Yi-chen Lin ◽  
Hong-yu Chen ◽  
Xiao-ru Liu

Abstract Background To investigate the function of transient receptor potential melastatin 2 (TRPM2) in vascular reactivity induced by 5-hydroxytryptamine (5-HT) in the aorta during development of atherosclerosis in mice. Methods Forty mice were randomly divided into 4 groups: C57BL/6J on normal diet (C57 + ND), C57BL/6J on high-fat diet (C57 + HFD), apolipoprotein E gene knockout mice (ApoE−/−) on ND (ApoE−/− + ND), and ApoE−/− on HFD (ApoE−/− + HFD). They were fed with a ND or HFD for 16 weeks. Aortic TRPM2 expression and isometric contractions were analyzed. Results In the ApoE−/− + HFD group, body weight, blood glucose, and blood lipid concentrations were increased, and aortic plaques were developed. Compared with the other 3 groups, aortic TRPM2 mRNA and protein levels were significantly increased in the ApoE−/− + HFD group (P < 0.01). Aortic reactivity to 5-HT was enhanced in ApoE−/− + HFD mice with lower EC50 values. The enhanced reactivity to 5-HT was significantly inhibited by TRPM2 inhibitors, N-p-amylcinnamoyl anthranilic acid (1 µmol/l) and 2-aminoethyl diphenylborinate (10 µmol/l). Conclusions Aortic TRPM2 expression is upregulated in ApoE knockout mice fed with a HFD. Upregulation of TRPM2 enhances 5-HT vascular reactivity during development of atherosclerosis.


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 ◽  
pp. 1-13
Author(s):  
Jiachen Liu ◽  
Laijiang Chen ◽  
Jun Huang ◽  
Shujie Guo ◽  
Dingliang Zhu ◽  
...  

Remodeling of the arteries is one of the pathological bases of hypertension. We have previously shown that transient receptor potential melastatin 7 (TRPM7) aggravates the vascular adventitial remodeling caused by pressure overload in the transverse aortic constriction (TAC) model. In this study, we sought to explore the functional expression and downstream signaling of TRPM7 in vascular adventitial fibroblasts (AFs) stimulated by mechanical stretching stress (MSS). The expression of TRPM7 was upregulated with a concomitant translocation to the cytoplasm in the AFs stimulated with 20% MSS. Meanwhile, the expression of α-smooth muscle actin (α-SMA), a marker of transformation from AFs to myofibroblasts (MFs) was also increased. Moreover, AF-conditioned medium caused a significant migration of macrophages after treatment with MSS and contained high levels of monocyte chemotactic protein-1 (MCP-1), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α). Pharmacological and RNA interference approaches using the TRPM7 inhibitor 2-aminoethoxydiphenyl borate (2-APB) and specific anti-TRPM7 small interfering RNA (si­RNA-TRPM7) abrogated these changes significantly. Further exploration uncloaked that inhibition of TRPM7 reduced the phosphorylation of p38 MAP kinase (p38MAPK) and c-Jun N-terminal kinase (JNK) in the AFs stimulated with MSS. Furthermore, inhibition of the phosphorylation of p38MAPK or JNK could also alleviate the MSS-induced expression of α-SMA and secretion of inflammatory factors. These observations indicate that activated TRPM7 participates in the phenotypic transformation and inflammatory action of AFs in response to MSS through the p38MAPK/JNK pathway and suggest that TRPM7 may be a potential therapeutic target for vascular remodeling caused by hemodynamic changes in hypertension.


Sign in / Sign up

Export Citation Format

Share Document