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Sprouty1 (Spry1) is a negative modulator of receptor tyrosine kinase signaling, but its role in cardiomyocyte survival has not been elucidated. The aim of this study was to investigate the potential role of cardiomyocyte Spry1 in cardiac ischemia–reperfusion (I/R) injury. Infarct areas of mouse hearts showed an increase in Spry1 protein expression, which localized to cardiomyocytes. To investigate if cardiomyocyte Spry1 regulates I/R injury, 8-week-old inducible cardiomyocyte Spry1 knockout (Spry1 cKO) mice and control mice were subjected to cardiac I/R injury. Spry1 cKO mice showed reduction in release of cardiac troponin I and reduced infarct size after I/R injury compared to control mice. Similar to Spry1 knockdown in cardiomyocytes in vivo, RNAi-mediated Spry1 silencing in isolated cardiomyocytes improved cardiomyocyte survival following simulated ischemia injury. Mechanistically, Spry1 knockdown induced cardiomyocyte extracellular signal-regulated kinase (ERK) phosphorylation in healthy hearts and isolated cardiomyocytes, and enhanced ERK phosphorylation after I/R injury. Spry1-deficient cardiomyocytes showed better preserved mitochondrial membrane potential following ischemic injury and an increase in levels of phosphorylated ERK and phosphorylated glycogen synthase kinase-3β (GSK-3β) in mitochondria of hypoxic cardiomyocytes. Overexpression of constitutively active GSK-3β abrogated the protective effect of Spry1 knockdown. Moreover, pharmacological inhibition of GSK-3β protected wild-type cardiomyocytes from cell death, but did not further protect Spry1-silenced cardiomyocytes from hypoxia-induced injury. Cardiomyocyte Spry1 knockdown promotes ERK phosphorylation and offers protection from I/R injury. Our findings indicate that Spry1 is an important regulator of cardiomyocyte viability during ischemia–reperfusion injury.

Brain glycogen synthase kinase-3 (GSK3) is hyperactive in several neurological conditions that involve impairments in both cognition and neurogenesis. This raises the hypotheses that hyperactive GSK3 may directly contribute to impaired cognition, and that this may be related to deficiencies in neural precursor cells (NPC). To study the effects of hyperactive GSK3 in the absence of disease influences, we compared adult hippocampal NPC proliferation and performance in three cognitive tasks in male and female wild-type (WT) mice and GSK3 knockin mice, which express constitutively active GSK3. NPC proliferation was 40% deficient in both male and female GSK3 knockin mice compared with WT mice. Environmental enrichment (EE) increased NPC proliferation in male, but not female, GSK3 knockin mice and WT mice. Male and female GSK3 knockin mice exhibited impairments in novel object recognition, temporal order memory, and coordinate spatial processing compared with gender-matched WT mice. EE restored impaired novel object recognition and temporal ordering in both sexes of GSK3 knockin mice, indicating that this repair was not dependent on NPC proliferation, which was not increased by EE in female GSK3 knockin mice. Acute 1 h pretreatment with the GSK3 inhibitor TDZD-8 also improved novel object recognition and temporal ordering in male and female GSK3 knockin mice.These findings demonstrate that hyperactive GSK3 is sufficient to impair adult hippocampal NPC proliferation and to impair performance in three cognitive tasks in both male and female mice, but these changes in NPC proliferation do not directly regulate novel object recognition and temporal ordering tasks.

Glycogen synthase kinase-3beta (GSK-3beta) has been demonstrated to play a critical role in a diverse range of cellular functions from cell fate determination to cancer development. It is also implicated to be involved in the pathogenesis of neurodegenerative diseases (e.g. Alzheimer's disease), cancers and endocrine disorders (e.g. Type II diabetes). To gain further insight into the cellular mechanisms mediated by GSK-3beta, proteomic approach to identify novel cellular targets has become popular in recent years. GSK-3beta was inhibited by treating with lithium and kenpaullone in SH-SY5Y cell model, and over-expressed in Chinese Hamster Ovary (CHO) Tet-Off cell model. To getting more reliable results, we have used both conventional 2-D approach and Difference Gel Electrophoresis (DIGE) approach for this proteomic study. In 2-D electrophoresis, samples were resolved by two-dimensional polyacrylamide gel-electrophoresis (2D-PAGE). Protein spots were excised from the gels for in-gel trypsin digestion and further subjected to protein identification using mass spectrometry (MALDI-TOF-MS or MS/MS). In the GSK-3beta inhibition approach, cofilin was found to be down-regulated and Pin1 was found to be up-regulated, these consequence events demonstrated inhibition of GSK-3beta would protect the cells from structure alteration and tau hyperphosphorylation. In the GSK-3beta activation approach, cyclin-dependent kinase 5 (CDK-5) was found to significantly up-regulated in tau and GSK-3beta/Tau over-expressed cells, confirmed by Western blotting and RT-PCR. This finding indicates there is a new pathway between GSK-3beta, tau and CDK-5. Pin1 is also identified to be up-regulated after GSK-3beta activation. This result indicated a protection mechanism in response to the accumulation of hyperphosphorylated tau proteins. Our study help to get a better understanding of the GSK-3beta mediated substrates and pathways that help us to identify novel targets for the treatment of neurodegen, Mak, Ying Cheong., "September 2007.", Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4588., Thesis (Ph.D.)--Chinese University of Hong Kong, 2007., Includes bibliographical references (p. 157-181)., Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web., Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web., s in English and Chinese., School code: 1307., isbn: 9780549774570, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Glycogen synthase kinase-3beta (GSK-3beta) has been demonstrated to play a critical role in a diverse range of cellular functions from cell fate determination to cancer development. It is also implicated to be involved in the pathogenesis of neurodegenerative diseases (e.g. Alzheimer's disease), cancers and endocrine disorders (e.g. Type II diabetes). To gain further insight into the cellular mechanisms mediated by GSK-3beta, proteomic approach to identify novel cellular targets has become popular in recent years. GSK-3beta was inhibited by treating with lithium and kenpaullone in SH-SY5Y cell model, and over-expressed in Chinese Hamster Ovary (CHO) Tet-Off cell model. To getting more reliable results, we have used both conventional 2-D approach and Difference Gel Electrophoresis (DIGE) approach for this proteomic study. In 2-D electrophoresis, samples were resolved by two-dimensional polyacrylamide gel-electrophoresis (2D-PAGE). Protein spots were excised from the gels for in-gel trypsin digestion and further subjected to protein identification using mass spectrometry (MALDI-TOF-MS or MS/MS). In the GSK-3beta inhibition approach, cofilin was found to be down-regulated and Pin1 was found to be up-regulated, these consequence events demonstrated inhibition of GSK-3beta would protect the cells from structure alteration and tau hyperphosphorylation. In the GSK-3beta activation approach, cyclin-dependent kinase 5 (CDK-5) was found to significantly up-regulated in tau and GSK-3beta/Tau over-expressed cells, confirmed by Western blotting and RT-PCR. This finding indicates there is a new pathway between GSK-3beta, tau and CDK-5. Pin1 is also identified to be up-regulated after GSK-3beta activation. This result indicated a protection mechanism in response to the accumulation of hyperphosphorylated tau proteins. Our study help to get a better understanding of the GSK-3beta mediated substrates and pathways that help us to identify novel targets for the treatment of neurodegen, Mak, Ying Cheong., "September 2007.", Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4588., Thesis (Ph.D.)--Chinese University of Hong Kong, 2007., Includes bibliographical references (p. 157-181)., Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web., Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web., s in English and Chinese., School code: 1307., isbn: 9780549774570, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

by Wong Kin Kwan Kelvin., Thesis submitted in: September 2004., Thesis (M.Phil.)--Chinese University of Hong Kong, 2005., Includes bibliographical references (leaves 91-101)., s in English and Chinese., Acknowledgements --- p.i, p.ii, 摘要 --- p.iv, Abbreviations --- p.x, List of Figures --- p.xiii, List of Tables --- p.xiv, Chapter Chapter 1 --- Intorduction --- p.1, Chapter 1.1 --- Alzheimer，s disease --- p.1, Chapter 1.2 --- Histopathological features --- p.1, Chapter 1.3 --- Tau protein pathology and AD --- p.4, Chapter 1.4 --- Tau protein kinase I (TPKI)- GSK-3β --- p.6, Chapter 1.5 --- Tau protein kinase II (TPKII)- Cyclin dependent kinase 5 (Cdk5) --- p.8, Chapter 1.6 --- Available treatment --- p.9, Chapter 1.7 --- Objectives of the present study --- p.12, Chapter Chapter 2 --- Screening for GSK-3p inhibitors from Traditional Chinese Medicine (TCM) --- p.13, Chapter 2.1 --- Introduction --- p.13, Chapter 2.1.1 --- Phosphorylation of tau in AD --- p.13, Chapter 2.1.2 --- Gsk-3p inhibitors --- p.14, Chapter 2.1.3 --- Screening of GSK-3β inhibitor from TCM --- p.16, Chapter 2.2 --- Material and Methods --- p.18, Chapter 2.2.1 --- Preparation of extracts and fractions (AOF1-5) --- p.18, Chapter 2.2.2 --- General cell culture techniques --- p.21, Chapter 2.2.3 --- "3-(4,5-dimethyltiazoI-2-yl)-2, 5-diphenyl-tetrazolium (MTT) assay of AOF" --- p.23, Chapter 2.2.4 --- Recombinant DNA techniques --- p.23, Chapter 2.2.5 --- Transfection of GSK-3β and tau cDNA into COS7 cells --- p.28, Chapter 2.2.6 --- Extraction of total proteins from culture cells --- p.28, Chapter 2.2.7 --- Quantitation of protein by the Bradford method --- p.29, Chapter 2.2.8 --- Protein separation by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.29, Chapter 2.2.9 --- Western blot analysis --- p.31, Chapter 2.2.10 --- GSK-3β kinase assay --- p.32, Chapter 2.2.11 --- Determination of lithium content by atomic adsorption spectrophotometry --- p.34, Chapter 2.3 --- Results --- p.35, Chapter 2.3.1 --- Establishment of a co-transfected cell model for GSK-3β induced tau hyperphosphorylation --- p.35, Chapter 2.3.2 --- Preliminary screening results of aqueous and ethanol extracts (AOF1 and AOF2) --- p.37, Chapter 2.3.3 --- Ethanol extract of AOF inhibits GSK-3p induced tau phosphorylation in COS-7 cells --- p.40, Chapter 2.3.5 --- Effect of the essential oils of AOF on GSK-3P induced tau phosphorylation --- p.46, Chapter 2.3.6 --- The effect of AOF essential oil on GSK-3P activity in COS7 --- p.50, Chapter 2.3.7 --- Lithium content of AOF extracts --- p.52, Chapter 2.4 --- Discussion --- p.54, Chapter Chapter 4 --- Evaluation of the in vivo efficacy of cryptotenshinone (CT) in Morris Water Maze Task (WMT) --- p.59, Chapter 4.1 --- Introduction --- p.59, Chapter 4.1.1 --- Involvement of Cholinergic system in cognitive dysfunction in AD --- p.59, Chapter 4.1.2 --- Animal model for Alzheimer's disease --- p.60, Chapter 4.1.3 --- Morris Watermaze Task (WMT) --- p.61, Chapter 4.2 --- MATERIAL AND METHODS --- p.64, Chapter 4.2.1 --- Morris Water maze setup --- p.64, Chapter 4.2.2 --- Animal model --- p.66, Chapter 4.2.3 --- Drug preparation --- p.67, Chapter 4.2.4 --- Toxicity test of CT --- p.67, Chapter 4.2.5 --- Water maze task (WMT) --- p.68, Chapter 4.2.6 --- Visual acuity test --- p.73, Chapter 4.3 --- RESULTS --- p.74, Chapter 4.3.1 --- Chronic crytotanshinone treatment does not cause hepatic damages to the mice --- p.74, Chapter 4.3.2 --- Training Session --- p.76, Chapter 4.4 --- DISCUSSION --- p.85, Chapter Chapter 5 --- General Discussion and Future Directions --- p.87, Chapter 5.1 --- "AOF, the potential GSK-3 inhibitor" --- p.87, Chapter 5.2 --- CT´ؤthe AChEI --- p.88, References --- p.91, Appendix --- p.102, Chapter A1 --- Reagents for SDS-PAGE --- p.103, Chapter A3 --- Solution components provided by QIAGEN Plasmid Maxipreps kit --- p.108, Chapter A4 --- Reagents and medium for cell culture --- p.109, Chapter A5 --- Reagents for kinase assay --- p.110, Chapter A6 --- Raw data of figures --- p.112, Chapter A7 --- Plasmid map of PCI-neo --- p.119, http://library.cuhk.edu.hk/record=b5896404, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Two cellular systems have been used to investigate the modulation of tau hyperphosphorylation. In the first system, the effects of the excitatory amino acid glutamate, the microtubule destabilising agent colchicine, and beta 25-35-amyloid peptide on tau phosphorylation were studied in rat cortical neurones in primary culture. Using immunocytochemistry and western blot analysis, we demonstrated that tau in these cultures is normally highly phosphorylated, but a proportion becomes rapidly dephosphorylated following treatment of the cultures with glutamate or colchicine. These changes in tau phosphorylation occurred prior to cell death. In the second system, the ability of p42 MAP and p44 MAP kinases, glycogen synthase kinases 3 alpha and 3 beta (GSK-3 alpha and GSK-3 beta) to phosphorylate tau in transfected COS cells was investigated. Both GSK-3 alpha and GSK-3 beta phosphorylated tau to produce a PHF-like state of phosphorylation but the MAP kinases failed to induce such a transformation in tau. These results suggest that aberrant regulation of GSK-3 alpha/beta may be a pathogenic mechanism in Alzheimer's disease., Journal Article, Research Support, Non-U.S. Gov't, SCOPUS: ar.j, info:eu-repo/semantics/published

Glycogen synthase kinase-3 (GSK-3) reduced the mobility of human tau on SDS-PAGE, prevented binding of the monoclonal antibody (mAb), Tau.1, and induced binding of the mAb 8D8. Recombinant tau phosphorylated by GSK-3 aligned on SDS-PAGE with the abnormally phosphorylated tau (PHF-tau) associated with the paired helical filaments in Alzheimer's disease brain. Phosphorylated serine396 (numbering of the largest human brain tau isoform) was identified as a binding site on tau for mAb 8D8. The localisation of GSK-3 within granular structures in pyramidal cells indicates that GSK-3 alpha and GSK-3 beta may have a role in the production of PHF-tau in Alzheimer's disease., Journal Article, Research Support, Non-U.S. Gov't, SCOPUS: ar.j, info:eu-repo/semantics/published

Glycogen synthase kinase-3 (GSK-3) reduced the mobility of human tau on SDS-PAGE, prevented binding of the monoclonal antibody (mAb), Tau.1, and induced binding of the mAb 8D8. Recombinant tau phosphorylated by GSK-3 aligned on SDS-PAGE with the abnormally phosphorylated tau (PHF-tau) associated with the paired helical filaments in Alzheimer's disease brain. Phosphorylated serine396 (numbering of the largest human brain tau isoform) was identified as a binding site on tau for mAb 8D8. The localisation of GSK-3 within granular structures in pyramidal cells indicates that GSK-3 alpha and GSK-3 beta may have a role in the production of PHF-tau in Alzheimer's disease., Journal Article, Research Support, Non-U.S. Gov't, SCOPUS: ar.j, info:eu-repo/semantics/published

Thota, R. N., Rosato, J. I., Burrows, T. L., Dias, C. B., Abbott, K. A., Martins, R. N., & Garg, M. L. (2020). Docosahexaenoic acid-rich fish oil supplementation reduces kinase associated with insulin resistance in overweight and obese midlife adults. Nutrients, 12(6), 1612. https://doi.org/10.3390/nu12061612