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Cavaleri F, Chattopadhyay S, Palsule V, Kar PK, Chatterjee R. Study of Drug Target Identification and Associated Molecular Mechanisms for the Therapeutic Activity and Hair Follicle Induction of Two Ashwagandha Extracts Having Differential Withanolide Constitutions. J Nutr Metab 2023; 2023:9599744. [PMID: 37808919 PMCID: PMC10560109 DOI: 10.1155/2023/9599744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 08/18/2023] [Accepted: 08/19/2023] [Indexed: 10/10/2023] Open
Abstract
Background Ashwagandha extracts play a significant role in traditional Indian medicine to help treat a wide range of disorders from amnesia, erectile dysfunction, neurodegenerative and cardiovascular diseases, cancer, stress, anxiety, and many more. Ashwagandha root is enriched with bioactive plant metabolites of which withanolides are the most important ones. The concentration and constitution of withanolides primarily determine ashwagandha's potency and pharmacology. Various factors modulate the withanolide constitution in the plant-derived extracts, rendering inconsistent therapeutic efficacy. Standardisation of the extraction protocol and a better understanding of the pharmacology mechanism of different extracts with varied withanolide constitutions is therefore critical for developing reliable, repeatable, and effective ashwagandha-based treatment. Objectives Here, we work toward defining indication mechanisms for two varieties of ashwagandha extract-ASHWITH (ASH-Ext1) and Regenolide (ASH-Ext2)-with different proprietary withanolide proportions. Methods ASH-Ext1 was studied for antioxidant signaling modulation using HEK293, HeLa, and A549 cells, and ASH-Ext2 was studied for subcellular drug targets associated with the reactivation and longevity of human hair follicles, using primary human hair follicle dermal papilla cells (HFDPCs). Results Study findings support the antioxidant activity and Nrf2 signaling modulation by ASH-Ext1 in various cell models. Of note, ASH-Ext2 was found to increase β-catenin and telomerase reverse transcriptase (TERT) protein expression levels in HFDPCs. Conclusion The results of drug target modulation show us that the withanolide constitution associated with different extraction protocols influences the pharmacological potential of the extract significantly and points to the value of standardisation not only of total withanolide content but also of internal withanolide proportions.
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Affiliation(s)
- Franco Cavaleri
- Biologic Pharmamedical Research, 688-2397 King George Blvd, White Rock V4A 7E9, BC, Canada
- Cooch Behar Panchanan Barma University, Panchanan Nagar, Vivekananda Street, Cooch Behar 736101, West Bengal, India
| | - Sukalpa Chattopadhyay
- Biologic Pharmamedical Research, 688-2397 King George Blvd, White Rock V4A 7E9, BC, Canada
| | - Vrushalee Palsule
- Biologic Pharmamedical Research, 688-2397 King George Blvd, White Rock V4A 7E9, BC, Canada
| | - Pradip Kumar Kar
- Cooch Behar Panchanan Barma University, Panchanan Nagar, Vivekananda Street, Cooch Behar 736101, West Bengal, India
| | - Ritam Chatterjee
- Cooch Behar Panchanan Barma University, Panchanan Nagar, Vivekananda Street, Cooch Behar 736101, West Bengal, India
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Ahmadi S, Dadashpour M, Abri A, Zarghami N. Long-term proliferation and delayed senescence of bone marrow-derived human mesenchymal stem cells on metformin co-embedded HA/Gel electrospun composite nanofibers. J Drug Deliv Sci Technol 2022. [DOI: 10.1016/j.jddst.2022.104071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Wang L, Zhang Y, Yu M, Yuan W. Identification of Hub Genes in the Remodeling of Non-Infarcted Myocardium Following Acute Myocardial Infarction. J Cardiovasc Dev Dis 2022; 9:jcdd9120409. [PMID: 36547406 PMCID: PMC9788553 DOI: 10.3390/jcdd9120409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/18/2022] [Accepted: 11/20/2022] [Indexed: 11/23/2022] Open
Abstract
(1) Background: There are few diagnostic and therapeutic targets for myocardial remodeling in the salvageable non-infarcted myocardium. (2) Methods: Hub genes were identified through comprehensive bioinformatics analysis (GSE775, GSE19322, and GSE110209 from the gene expression omnibus (GEO) database) and the biological functions of hub genes were examined by gene ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. Furthermore, the differential expression of hub genes in various cell populations between the acute myocardial infarction (AMI) and sham-operation groups was analyzed by processing scRNA data (E-MTAB-7376 from the ArrayExpress database) and RNA-seq data (GSE183168). (3) Results: Ten strongly interlinked hub genes (Timp1, Sparc, Spp1, Tgfb1, Decr1, Vim, Serpine1, Serpina3n, Thbs2, and Vcan) were identified by the construction of a protein-protein interaction network from 135 differentially expressed genes identified through comprehensive bioinformatics analysis and their reliability was verified using GSE119857. In addition, the 10 hub genes were found to influence the ventricular remodeling of non-infarcted tissue by modulating the extracellular matrix (ECM)-mediated myocardial fibrosis, macrophage-driven inflammation, and fatty acid metabolism. (4) Conclusions: Ten hub genes were identified, which may provide novel potential targets for the improvement and treatment of AMI and its complications.
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Serati-Nouri H, Mahmoudnezhad A, Bayrami M, Sanajou D, Tozihi M, Roshangar L, Pilehvar Y, Zarghami N. Sustained delivery efficiency of curcumin through ZSM-5 nanozeolites/electrospun nanofibers for counteracting senescence of human adipose-derived stem cells. J Drug Deliv Sci Technol 2021. [DOI: 10.1016/j.jddst.2021.102902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Pluripotent stem cell-derived mesenchymal stromal cells improve cardiac function and vascularity after myocardial infarction. Cytotherapy 2021; 23:1074-1084. [PMID: 34588150 DOI: 10.1016/j.jcyt.2021.07.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 01/10/2023]
Abstract
BACKGROUND AIMS Mesenchymal stromal cells (MSCs) have been shown to improve cardiac function after injury and are the subject of ongoing clinical trials. In this study, the authors tested the cardiac regenerative potential of an induced pluripotent stem cell-derived MSC (iPSC-MSC) population (Cymerus MSCs) in a rat model of myocardial ischemia-reperfusion (I/R). Furthermore, the authors compared this efficacy with bone marrow-derived MSCs (BM-MSCs), which are the predominant cell type in clinical trials. METHODS Four days after myocardial I/R injury, rats were randomly assigned to (i) a Cymerus MSC group (n = 15), (ii) a BM-MSC group (n = 15) or (iii) a vehicle control group (n = 14). For cell-treated animals, a total of 5 × 106 cells were injected at three sites within the infarcted left ventricular (LV) wall. RESULTS One month after cell transplantation, Cymerus MSCs improved LV function (assessed by echocardiography) compared with vehicle and BM-MSCs. Interestingly, Cymerus MSCs enhanced angiogenesis without sustained engraftment or significant impact on infarct scar size. Suggesting safety, Cymerus MSCs had no effect on inducible tachycardia or the ventricular scar heterogeneity that provides a substrate for cardiac re-entrant circuits. CONCLUSIONS The authors here demonstrate that intra-myocardial administration of iPSC-MSCs (Cymerus MSCs) provide better therapeutic effects compared with conventional BM-MSCs in a rodent model of myocardial I/R. Because of its manufacturing scalability, iPSC-MSC therapy offers an exciting opportunity for an "off-the-shelf" stem cell therapy for cardiac repair.
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Rashid FN, Clayton ZE, Ogawa M, Perdomo J, Hume RD, Kizana E, Chong JJH. Platelet derived growth factor-A (Pdgf-a) gene transfer modulates scar composition and improves left ventricular function after myocardial infarction. Int J Cardiol 2021; 341:24-30. [PMID: 34265313 DOI: 10.1016/j.ijcard.2021.07.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 06/18/2021] [Accepted: 07/08/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND Novel therapies that can limit or reverse damage caused by myocardial infarction (MI) could ease the increasing burden of heart failure. In this regard Platelet Derived Growth Factor (PDGF) has been previously shown to contribute to cardiac repair after MI. Here, we use a rodent model of MI and recombinant adeno-associated virus 9 (rAAV9)-mediated gene transfer to overexpress Pdgf-a in the injured heart and assess its therapeutic potential. METHODS AND RESULTS Sprague Dawley rats underwent temporary occlusion of the left anterior descending coronary artery, followed immediately by systemic delivery of 1 × 10^11 vector genomes of either rAAV9 Pdgf-a or rAAV9 Empty vector (control). At day 28 post-MI echocardiography showed significantly improved left ventricular (LV) function (fractional shortening) after rAAV9 Pdgf-a (0.394 ± 0.019%) treatment vs control (0.304 ± 0.018%). Immunohistochemical analysis demonstrated significantly increased capillary and arteriolar density in the infarct border zone of rAAV9 Pdgf-a treated hearts together with a significant reduction in infarct scar size (rAAV9 Pdgf-a 6.09 ± 0.94% vs Empty 12.45 ± 0.92%). Western blot and qPCR analyses confirmed overexpression of PDGF-A and showed upregulation of smooth muscle alpha actin (Acta2), collagen type III alpha 1 (Col3a1) and lysyl oxidase (Lox) genes in rAAV9 Pdgf-a treated infarcts. CONCLUSION Overexpression of Pdgf-a in the post-MI heart can modulate scar composition and improve LV function. Our study highlights the potential of rAAV gene transfer of Pdgf-a as a cardio-reparative therapy.
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Affiliation(s)
- Fairooj N Rashid
- Centre for Heart Research, Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead 2145, NSW, Australia; The University of Sydney, Australia
| | - Zoë E Clayton
- Centre for Heart Research, Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead 2145, NSW, Australia; The University of Sydney, Australia
| | - Masahito Ogawa
- Centre for Heart Research, Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead 2145, NSW, Australia; The University of Sydney, Australia
| | - Jose Perdomo
- Haematology Research Unit, St George and Sutherland Clinical School, University of New South Wales, NSW, Australia
| | - Robert D Hume
- Centre for Heart Research, Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead 2145, NSW, Australia; The University of Sydney, Australia
| | - Eddy Kizana
- Centre for Heart Research, Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead 2145, NSW, Australia; The University of Sydney, Australia; Department of Cardiology, Westmead Hospital, Westmead 2145, NSW, Australia; Sydney Medical School, Faculty of Medicine and Health, University of Sydney, NSW, Australia
| | - James J H Chong
- Centre for Heart Research, Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead 2145, NSW, Australia; The University of Sydney, Australia; Department of Cardiology, Westmead Hospital, Westmead 2145, NSW, Australia; Sydney Medical School, Faculty of Medicine and Health, University of Sydney, NSW, Australia.
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Koohsarian P, Talebi A, Rahnama MA, Zomorrod MS, Kaviani S, Jalili A. Reviewing the role of cardiac exosomes in myocardial repair at a glance. Cell Biol Int 2021; 45:1352-1363. [PMID: 33289229 DOI: 10.1002/cbin.11515] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 11/14/2020] [Accepted: 11/28/2020] [Indexed: 12/11/2022]
Abstract
Exosome-based therapy is an emerging novel approach for myocardial infarction (MI) treatment. Exosomes are identified as extracellular vesicles that are produced within multivesicular bodies in the cells' cytosols and then are secreted from the cells. Exosomes are 30-100 nm in diameter that are released from viable cells and are different from other secreted vesicles such as apoptotic bodies and microvesicles in their origin and contents such as RNAs, proteins, and nucleic acid. The recent advances in exosome research have demonstrated the role of these bionanovesicles in the physiological, pathological, and molecular aspects of the heart. The results of in vitro and preclinical models have shown that exosomes from different cardiac cells can improve cardiac function following MI. For example, mesenchymal stem cells (MSCs) and cardiac progenitor cells (CPCs) containing exosomes can affect the proliferation, survival, and differentiation of cardiac fibroblasts and cardiomyocytes. Moreover, MSCs- and CPCs-derived exosomes can enhance the migration of endothelial cells. Exosome-based therapy approaches augment the cardiac function by multiple means, such as reducing fibrosis, stimulation of vascular angiogenesis, and proliferation of cardiomyocytes that result in replacing damaged heart tissue with newly generated functional myocytes. This review article aims to briefly discuss the recent advancements in the role of secreted exosomes in myocardial repair by focusing on cardiac cells-derived exosomes.
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Affiliation(s)
- Parisa Koohsarian
- Department of Hematology and Cell Therapy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Athar Talebi
- Department of Nervous System, Stem Cell Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | - Mahshid A Rahnama
- Department of Hematology and Cell Therapy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mina S Zomorrod
- Department of Hematology and Cell Therapy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Saeid Kaviani
- Department of Hematology and Cell Therapy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Arsalan Jalili
- Department of Stem Cells and Developmental Biology at Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.,Hematopoetic Stem Cell Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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The Impact of Spaceflight and Microgravity on the Human Islet-1+ Cardiovascular Progenitor Cell Transcriptome. Int J Mol Sci 2021; 22:ijms22073577. [PMID: 33808224 PMCID: PMC8036947 DOI: 10.3390/ijms22073577] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 03/27/2021] [Accepted: 03/27/2021] [Indexed: 12/11/2022] Open
Abstract
Understanding the transcriptomic impact of microgravity and the spaceflight environment is relevant for future missions in space and microgravity-based applications designed to benefit life on Earth. Here, we investigated the transcriptome of adult and neonatal cardiovascular progenitors following culture aboard the International Space Station for 30 days and compared it to the transcriptome of clonally identical cells cultured on Earth. Cardiovascular progenitors acquire a gene expression profile representative of an early-stage, dedifferentiated, stem-like state, regardless of age. Signaling pathways that support cell proliferation and survival were induced by spaceflight along with transcripts related to cell cycle re-entry, cardiovascular development, and oxidative stress. These findings contribute new insight into the multifaceted influence of reduced gravitational environments.
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White SJ, Chong JJH. Mesenchymal Stem Cells in Cardiac Repair: Effects on Myocytes, Vasculature, and Fibroblasts. Clin Ther 2020; 42:1880-1891. [PMID: 32938532 DOI: 10.1016/j.clinthera.2020.08.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/09/2020] [Accepted: 08/17/2020] [Indexed: 12/31/2022]
Abstract
PURPOSE Cardiac pathologies remain a dominant cause of morbidity and mortality within the community. The drive to develop therapies capable of repairing damaged heart tissue to achieve clinically significant restoration of function has motivated the pursuit of novel approaches such as cell therapy. To this end, evidence of therapeutic benefits achieved by using mesenchymal stem cells (MSCs) has captured considerable interest despite a relative lack of information regarding the mechanisms involved. This narrative review synthesizes and interprets the current literature describing mechanisms by which MSCs can elicit cardiac repair, thereby directing attention to avenues of further inquiry. METHODS OVID versions of MEDLINE and EMBASE were searched for studies describing the role of MSCs in mammalian cardiac repair. Additional studies were sourced from the reference lists of relevant articles and other personal files. FINDINGS MSCs elicit cardiac repair in a range of in vitro systems and animal models of diseases such as myocardial infarction and heart failure. Important mechanisms include the preservation of myocardial contractility, the promotion of angiogenesis, and the modulation of fibrosis. Exposing in vitro MSCs to a microenvironment reflective of that encountered in the injured heart seems to potentiate these therapeutic mechanisms. IMPLICATIONS Promising results in animal studies warrant continuation of clinical MSC cardiac therapy studies. Paracrine functions of MSCs seem to be the dominant mechanism of cardiac repair over direct cellular effects. Although integral, the MSC secretome remains poorly defined. In addition, most of the mechanistic data within the literature have been derived from animal MSC research, necessitating more human MSC-based work.
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Affiliation(s)
- Samuel J White
- Sydney Medical School, Faculty of Medicine and Health, The University of Sydney, Camperdown, New South Wales, Australia
| | - James J H Chong
- Centre for Heart Research, Westmead Institute for Medical Research, The University of Sydney, Westmead, New South Wales, Australia; Department of Cardiology, Westmead Hospital, Westmead, New South Wales, Australia.
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Stadiotti I, Piacentini L, Vavassori C, Chiesa M, Scopece A, Guarino A, Micheli B, Polvani G, Colombo GI, Pompilio G, Sommariva E. Human Cardiac Mesenchymal Stromal Cells From Right and Left Ventricles Display Differences in Number, Function, and Transcriptomic Profile. Front Physiol 2020; 11:604. [PMID: 32670081 PMCID: PMC7327120 DOI: 10.3389/fphys.2020.00604] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 05/14/2020] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Left ventricle (LV) and right ventricle (RV) are characterized by well-known physiological differences, mainly related to their different embryological origin, hemodynamic environment, function, structure, and cellular composition. Nevertheless, scarce information is available about cellular peculiarities between left and right ventricular chambers in physiological and pathological contexts. Cardiac mesenchymal stromal cells (C-MSC) are key cells affecting many functions of the heart. Differential features that distinguish LV from RV C-MSC are still underappreciated. AIM To analyze the physiological differential amount, function, and transcriptome of human C-MSC in LV versus (vs.) RV. METHODS Human cardiac specimens of LV and RV from healthy donors were used for tissue analysis of C-MSC number, and for C-MSC isolation. Paired LV and RV C-MSC were compared as for surface marker expression, cell proliferation/death ratio, migration, differentiation capabilities, and transcriptome profile. RESULTS Histological analysis showed a greater percentage of C-MSC in RV vs. LV tissue. Moreover, a higher C-MSC amount was obtained from RV than from LV after isolation procedures. LV and RV C-MSC are characterized by a similar proportion of surface markers. Functional studies revealed comparable cell growth curves in cells from both ventricles. Conversely, LV C-MSC displayed a higher apoptosis rate and RV C-MSC were characterized by a higher migration speed and collagen deposition. Consistently, transcriptome analysis showed that genes related to apoptosis regulation or extracellular matrix organization and integrins were over-expressed in LV and RV, respectively. Besides, we revealed additional pathways specifically associated with LV or RV C-MSC, including energy metabolism, inflammatory response, cardiac conduction, and pluripotency. CONCLUSION Taken together, these results contribute to the functional characterization of RV and LV C-MSC in physiological conditions. This information suggests a possible differential role of the stromal compartment in chamber-specific pathologic scenarios.
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Affiliation(s)
- Ilaria Stadiotti
- Unit of Vascular Biology and Regenerative Medicine, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Luca Piacentini
- Unit of Immunology and Functional Genomics, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Chiara Vavassori
- Unit of Immunology and Functional Genomics, Centro Cardiologico Monzino IRCCS, Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Mattia Chiesa
- Unit of Immunology and Functional Genomics, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Alessandro Scopece
- Unit of Vascular Biology and Regenerative Medicine, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Anna Guarino
- Cardiovascular Tissue Bank, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Barbara Micheli
- Cardiovascular Tissue Bank, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Gianluca Polvani
- Cardiovascular Tissue Bank, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | | | - Giulio Pompilio
- Unit of Vascular Biology and Regenerative Medicine, Centro Cardiologico Monzino IRCCS, Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Elena Sommariva
- Unit of Vascular Biology and Regenerative Medicine, Centro Cardiologico Monzino IRCCS, Milan, Italy
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Thompson CA, Wong JM. Non-canonical Functions of Telomerase Reverse Transcriptase: Emerging Roles and Biological Relevance. Curr Top Med Chem 2020; 20:498-507. [DOI: 10.2174/1568026620666200131125110] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 01/10/2020] [Accepted: 01/21/2020] [Indexed: 12/11/2022]
Abstract
Increasing evidence from research on telomerase suggests that in addition to its catalytic telomere
repeat synthesis activity, telomerase may have other biologically important functions. The canonical
roles of telomerase are at the telomere ends where they elongate telomeres and maintain genomic
stability and cellular lifespan. The catalytic protein component Telomerase Reverse Transcriptase
(TERT) is preferentially expressed at high levels in cancer cells despite the existence of an alternative
mechanism for telomere maintenance (alternative lengthening of telomeres or ALT). TERT is also expressed
at higher levels than necessary for maintaining functional telomere length, suggesting other possible
adaptive functions. Emerging non-canonical roles of TERT include regulation of non-telomeric
DNA damage responses, promotion of cell growth and proliferation, acceleration of cell cycle kinetics,
and control of mitochondrial integrity following oxidative stress. Non-canonical activities of TERT primarily
show cellular protective effects, and nuclear TERT has been shown to protect against cell death
following double-stranded DNA damage, independent of its role in telomere length maintenance. TERT
has been suggested to act as a chromatin modulator and participate in the transcriptional regulation of
gene expression. TERT has also been reported to regulate transcript levels through an RNA-dependent
RNA Polymerase (RdRP) activity and produce siRNAs in a Dicer-dependent manner. At the mitochondria,
TERT is suggested to protect against oxidative stress-induced mtDNA damage and promote mitochondrial
integrity. These extra-telomeric functions of TERT may be advantageous in the context of increased
proliferation and metabolic stress often found in rapidly-dividing cancer cells. Understanding
the spectrum of non-canonical functions of telomerase may have important implications for the rational
design of anti-cancer chemotherapeutic drugs.
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Affiliation(s)
- Connor A.H. Thompson
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, V6T 1Z3, Canada
| | - Judy M.Y. Wong
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, V6T 1Z3, Canada
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