Skip to content
Articles by Szu-Yi Chou in JoVE
-
Live Images of GLUT4 Protein Trafficking in Mouse Primary Hypothalamic Neurons Using Deconvolution Microscopy
Chun Austin Changou1,2,3, Reni Ajoy4,5, Szu-Yi Chou4,5,6
1The Ph.D. Program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, 2Integrated Laboratory, Center of Translational Medicine, Taipei Medical University, 3Core Facility, Taipei Medical University, 4The Ph.D. Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, 5Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, 6TMU research center for Neurotrauma and Neuroregeneration, College of Medical Science and Technology, Taipei Medical University
This protocol describes a technique for observation of real-time Green Fluorescence Protein (GFP) tagged Glucose Transporter 4 (GLUT4) protein trafficking upon insulin stimulation and characterization of the biological role of CCR5 in the insulin–GLUT4 signaling pathway with Deconvolution Microscopy.
-
Studying the Hypothalamic Insulin Signal to Peripheral Glucose Intolerance with a Continuous Drug Infusion System into the Mouse Brain
Reni Ajoy1,2, Szu-Yi Chou1,2,3
1The Ph.D. Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University and National Health Research, 2Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, 3TMU research center for Neurotrauma and Neuroregeneration, College of Medical Science and Technology, Taipei Medical University
This protocol studies the role of chemokine (C-C motif) ligand 5 (CCL5) in the hypothalamus by delivering an antagonist, MetCCL5, into the mouse brain using a micro-osmotic pump brain infusion system. This transient inhibition of CCL5 activity interrupted hypothalamic insulin signaling, leading to glucose intolerance and peripheral systemic insulin sensitivity.
Other articles by Szu-Yi Chou on PubMed
-
The Sigma-1 Receptor-zinc Finger Protein 179 Pathway Protects Against Hydrogen Peroxide-induced Cell Injury
Neuropharmacology.
|
Pubmed ID: 26792191 The accumulation of reactive oxygen species (ROS) have implicated the pathogenesis of several human diseases including neurodegenerative disorders, stroke, and traumatic brain injury, hence protecting neurons against ROS is very important. In this study, we focused on sigma-1 receptor (Sig-1R), a chaperone at endoplasmic reticulum, and investigated its protective functions. Using hydrogen peroxide (H2O2)-induced ROS accumulation model, we verified that apoptosis-signaling pathways were elicited by H2O2 treatment. However, the Sig-1R agonists, dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS), reduced the activation of apoptotic pathways significantly. By performing protein-protein interaction assays and shRNA knockdown of Sig-1R, we identified the brain Zinc finger protein 179 (Znf179) as a downstream target of Sig-1R regulation. The neuroprotective effect of Znf179 overexpression was similar to that of DHEAS treatment, and likely mediated by affecting the levels of antioxidant enzymes. We also quantified the levels of peroxiredoxin 3 (Prx3) and superoxide dismutase 2 (SOD2) in the hippocampi of wild-type and Znf179 knockout mice, and found both enzymes to be reduced in the knockout versus the wild-type mice. In summary, these results reveal that Znf179 plays a novel role in neuroprotection, and Sig-1R agonists may be therapeutic candidates to prevent ROS-induced damage in neurodegenerative and neurotraumatic diseases.
-
-
-
CCL5/RANTES Contributes to Hypothalamic Insulin Signaling for Systemic Insulin Responsiveness Through CCR5
Scientific Reports.
|
Pubmed ID: 27898058 Many neurodegenerative diseases are accompanied by metabolic disorders. CCL5/RANTES, and its receptor CCR5 are known to contribute to neuronal function as well as to metabolic disorders such as type 2 diabetes mellitus, obesity, atherosclerosis and metabolic changes after HIV infection. Herein, we found that the lack of CCR5 or CCL5 in mice impaired regulation of energy metabolism in hypothalamus. Immunostaining and co-immunoprecipitation revealed the specific expression of CCR5, associated with insulin receptors, in the hypothalamic arcuate nucleus (ARC). Both ex vivo stimulation and in vitro tissue culture studies demonstrated that the activation of insulin, and PI3K-Akt pathways were impaired in CCR5 and CCL5 deficient hypothalamus. The inhibitory phosphorylation of insulin response substrate-1 at Ser302 (IRS-1(S302)) but not IRS-2, by insulin was markedly increased in CCR5 and CCL5 deficient animals. Elevating CCR5/CCL5 activity induced GLUT4 membrane translocation and reduced phospho-IRS-1(S302) through AMPKα-S6 Kinase. Blocking CCR5 using the antagonist, (Met)CCL5, abolished the de-phosphorylation of IRS-1(S302) and insulin signal activation. In addition, intracerebroventricular delivery of (Met)CCL5 interrupted hypothalamic insulin signaling and elicited peripheral insulin responsiveness and glucose intolerance. Taken together, our data suggest that CCR5 regulates insulin signaling in hypothalamus which contributes to systemic insulin sensitivity and glucose metabolism.
-
Get cutting-edge science videos from JoVE sent straight to your inbox every month.
