1
|
Zhao L, Teng M, Shi D, Sun J, Li Y, Zhang Z, Zhu W, Wu F. Adverse impacts of environmentally relevant PFOS alternatives on mice pancreatic tissues. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 909:168649. [PMID: 37977398 DOI: 10.1016/j.scitotenv.2023.168649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 11/19/2023]
Abstract
Perfluorooctane sulfonate (PFOS) alternatives are chemicals that are used to make a range of products. Researchers have found that PFOS alternatives are probably no less toxic than PFOS, which has aroused concern. It has also revealed that the pancreas may be harmed by exposure to PFOS alternatives. However, there is insufficient evidence to demonstrate the toxicity mechanisms of PFOS alternatives. This study demonstrates the adverse effects of three PFOS alternatives on the pancreatic health of mice. After subchronic exposure to PFOS alternatives at environmentally relevant concentrations (800 μg/L perfluorohexanesulfonate, 800 μg/L perfluorobutanesulfonate, and 3 μg/L sodium ρ-perfluorous nonenoxybenzene sulfonate) via drinking water for 6 weeks, toxicity mechanisms were elucidated by examining histopathology, immunity, endoplasmic reticulum stress, 16S rRNA, and short-chain fatty acid targeted metabolomics. Sodium ρ-perfluorous nonenoxybenzene sulfonate significantly increased levels of TNF-α, IL-6, p-PERK, and ATF-4 and decreased the abundance of Akkermansia muciniphila and Lactobacillus reuteri. In addition, the three PFOS alternatives changed the composition of the gut microbiota in mice. Short-chain fatty acids, which are metabolites of the gut microbiota, also significantly decreased. Correlation analysis demonstrates that the alteration of gut microbes is related to the adverse effects on the mice pancreas. Results suggest that the murine pancreas may be toxic endpoints of PFOS alternatives. This study alerts the threats to human health and accelerates the toxicology research of an increasing number of emerging PFOS alternatives.
Collapse
Affiliation(s)
- Lihui Zhao
- College of Geoexploration Science and Technology, Jilin University, Changchun 130026, China
| | - Miaomiao Teng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Di Shi
- Research & Development Affairs Office, Tsinghua University, 100084, China
| | - Jiaqi Sun
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Yunxia Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Zixuan Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Wentao Zhu
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, China
| | - Fengchang Wu
- College of Geoexploration Science and Technology, Jilin University, Changchun 130026, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| |
Collapse
|
2
|
Michalak M. Calreticulin: Endoplasmic reticulum Ca 2+ gatekeeper. J Cell Mol Med 2023; 28:e17839. [PMID: 37424156 PMCID: PMC10902585 DOI: 10.1111/jcmm.17839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 06/21/2023] [Accepted: 06/27/2023] [Indexed: 07/11/2023] Open
Abstract
Endoplasmic reticulum (ER) luminal Ca2+ is vital for the function of the ER and regulates many cellular processes. Calreticulin is a highly conserved, ER-resident Ca2+ binding protein and lectin-like chaperone. Over four decades of studying calreticulin demonstrate that this protein plays a crucial role in maintaining Ca2+ supply under different physiological conditions, in managing access to Ca2+ and how Ca2+ is used depending on the environmental events and in making sure that Ca2+ is not misused. Calreticulin plays a role of ER luminal Ca2+ sensor to manage Ca2+ -dependent ER luminal events including maintaining interaction with its partners, Ca2+ handling molecules, substrates and stress sensors. The protein is strategically positioned in the lumen of the ER from where the protein manages access to and distribution of Ca2+ for many cellular Ca2+ -signalling events. The importance of calreticulin Ca2+ pool extends beyond the ER and includes influence of cellular processes involved in many aspects of cellular pathophysiology. Abnormal handling of the ER Ca2+ contributes to many pathologies from heart failure to neurodegeneration and metabolic diseases.
Collapse
Affiliation(s)
- Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| |
Collapse
|
3
|
Groenendyk J, Michalak M. Interplay between calcium and endoplasmic reticulum stress. Cell Calcium 2023; 113:102753. [PMID: 37209448 DOI: 10.1016/j.ceca.2023.102753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/05/2023] [Accepted: 05/06/2023] [Indexed: 05/22/2023]
Abstract
Cellular homeostasis is crucial for the healthy functioning of the organism. Disruption of cellular homeostasis activates endoplasmic reticulum (ER) stress coping responses including the unfolded protein response (UPR). There are three ER resident stress sensors responsible for UPR activation - IRE1α, PERK and ATF6. Ca2+ signaling plays an important role in stress responses including the UPR and the ER is the main Ca2+ storage organelle and a source of Ca2+ for cell signaling. The ER contains many proteins involved in Ca2+ import/export/ storage, Ca2+ movement between different cellular organelles and ER Ca2+ stores refilling. Here we focus on selected aspects of ER Ca2+ homeostasis and its role in activation of the ER stress coping responses.
Collapse
Affiliation(s)
- Jody Groenendyk
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
| |
Collapse
|
4
|
Tan YR, Shen SY, Shen HQ, Yi PF, Fu BD, Peng LY. The role of endoplasmic reticulum stress in regulation of intestinal barrier and inflammatory bowel disease. Exp Cell Res 2023; 424:113472. [PMID: 36634742 DOI: 10.1016/j.yexcr.2023.113472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 01/08/2023] [Indexed: 01/11/2023]
Abstract
Inflammatory bowel disease (IBD) is a chronic inflammatory disease involving the digestive tract, characterized by abdominal pain, diarrhea, rectal bleeding, and so on, which can make patients physically weakened and live difficultly. Although IBD has been recognized for many years, the pathogenesis of IBD has not yet been established and damage to intestinal barrier is thought to be closely associated with IBD. Intestinal barrier is an innate barrier that maintains the homeostasis of the intestinal environment and impedes pathogenic bacteria and toxins, and the endoplasmic reticulum (ER) has recently been found to be involved in maintaining the integrity of intestinal barrier. Endoplasmic reticulum stress (ERS) is a status of endoplasmic reticulum damaged when unfolded or misfolded proteins accumulate in excess of the degradation systematic clearance limit of the misfolded proteins. The regulation of ERS on protein folding synthesis and maintenance of cellular homeostasis is an important factor in influencing the integrity of the intestinal barrier. This paper mainly discusses the relationship between ERS and the intestinal barrier, aiming to understand the regulatory role of ERS on the intestinal barrier and the mechanism and to improve new solutions and notions for the treatment or prevention of IBD.
Collapse
Affiliation(s)
- Yue-Rong Tan
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, No. 5333 Xi'an Road, Changchun, Jilin, 130062, China
| | - Si-Yang Shen
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, No. 5333 Xi'an Road, Changchun, Jilin, 130062, China
| | - Hai-Qing Shen
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, No. 5333 Xi'an Road, Changchun, Jilin, 130062, China
| | - Peng-Fei Yi
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, No. 5333 Xi'an Road, Changchun, Jilin, 130062, China
| | - Ben-Dong Fu
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, No. 5333 Xi'an Road, Changchun, Jilin, 130062, China
| | - Lu-Yuan Peng
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, No. 5333 Xi'an Road, Changchun, Jilin, 130062, China.
| |
Collapse
|
5
|
Calnexin, More Than Just a Molecular Chaperone. Cells 2023; 12:cells12030403. [PMID: 36766745 PMCID: PMC9913998 DOI: 10.3390/cells12030403] [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: 01/04/2023] [Revised: 01/17/2023] [Accepted: 01/17/2023] [Indexed: 01/26/2023] Open
Abstract
Calnexin is a type I integral endoplasmic reticulum (ER) membrane protein with an N-terminal domain that resides in the lumen of the ER and a C-terminal domain that extends into the cytosol. Calnexin is commonly referred to as a molecular chaperone involved in the folding and quality control of membrane-associated and secreted proteins, a function that is attributed to its ER- localized domain with a structure that bears a strong resemblance to another luminal ER chaperone and Ca2+-binding protein known as calreticulin. Studies have discovered that the cytosolic C-terminal domain of calnexin undergoes distinct post-translational modifications and interacts with a variety of proteins. Here, we discuss recent findings and hypothesize that the post-translational modifications of the calnexin C-terminal domain and its interaction with specific cytosolic proteins play a role in coordinating ER functions with events taking place in the cytosol and other cellular compartments.
Collapse
|
6
|
Identifying a Novel Endoplasmic Reticulum-Related Prognostic Model for Hepatocellular Carcinomas. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:8248355. [PMID: 35915607 PMCID: PMC9338738 DOI: 10.1155/2022/8248355] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 05/11/2022] [Accepted: 06/20/2022] [Indexed: 12/18/2022]
Abstract
From the standpoint of the ER (endoplasmic reticulum), we were interested in identifying hub genes that impact clinical prognosis for HCC (hepatocellular carcinoma) patients and developing an ER-related prognostic model. Using TCGA-LIHC (The Cancer Genome Atlas-Liver Hepatocellular Carcinoma) and GSE14520 datasets, we conducted a series of analyses, which included differential gene screening, clinical prognostic analysis, Lasso regression, nomogram prediction, tumour clustering, gene functional enrichment, and tumour infiltration of immune cells. Following our screening for ER-related genes (
), we conducted a Lasso regression model to obtain five hub genes, KPNA2, FMO3, SPP1, KIF2C, and LPCAT1, using TCGA-LIHC as a training set. According to risk scores, HCC samples within either the TCGG-LIHC or GSE14520 cohort were categorized into high- and low-risk groups. Compared to the high-risk group of HCC patients, patients in the low-risk group had a better prognosis of OS (overall survival) or RFS (relapse-free survival). For TCGA-LIHC training set, with the factors of risk score, stage, age, and sex, we plotted a nomogram for 1-, 3-, and 5-year survival predictions. Our model demonstrated better clinical validity in both TCGA-LIHC and GSE14520 cohorts. Additionally, events related to biological enzyme activity, biological metabolic processes, or the cell cycle were associated with the prognostic risk of ER. Furthermore, two HCC prognosis-associated tumour clusters were identified by ER hub gene-based consensus clustering. Our findings indicated a link between ER prognostic signature-related high/low risk and tumour infiltration levels of several immune cells, such as “macrophages M2/M0” and “regulatory T cells (Tregs).” Overall, we developed a novel ER-related clinical prognostic model for HCC patients.
Collapse
|
7
|
Dicks N, Gutierrez K, Currin L, de Macedo MP, Glanzner WG, Mondadori RG, Michalak M, Agellon LB, Bordignon V. Tauroursodeoxycholic acid/TGR5 signaling promotes survival and early development of glucose-stressed porcine embryos†. Biol Reprod 2021; 105:76-86. [PMID: 33889948 PMCID: PMC8256098 DOI: 10.1093/biolre/ioab072] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/24/2021] [Accepted: 04/12/2021] [Indexed: 01/21/2023] Open
Abstract
Conditions of impaired energy and nutrient homeostasis, such as diabetes and obesity, are associated with infertility. Hyperglycemia increases endoplasmic reticulum stress as well as oxidative stress and reduces embryo development and quality. Oxidative stress also causes deoxyribonucleic acid damage, which impairs embryo quality and development. The natural bile acid tauroursodeoxycholic acid reduces endoplasmic reticulum stress and rescues developmentally incompetent late-cleaving embryos, as well as embryos subjected to nuclear stress, suggesting the endoplasmic reticulum stress response, or unfolded protein response, and the genome damage response are linked. Tauroursodeoxycholic acid acts via the Takeda-G-protein-receptor-5 to alleviate nuclear stress in embryos. To evaluate the role of tauroursodeoxycholic acid/Takeda-G-protein-receptor-5 signaling in embryo unfolded protein response, we used a model of glucose-induced endoplasmic reticulum stress. Embryo development was impaired by direct injection of tauroursodeoxycholic acid into parthenogenetically activated oocytes, whereas it was improved when tauroursodeoxycholic acid was added to the culture medium. Attenuation of the Takeda-G-protein-receptor-5 precluded the positive effect of tauroursodeoxycholic acid supplementation on development of parthenogenetically activated and fertilized embryos cultured under standard conditions and parthenogenetically activated embryos cultured with excess glucose. Moreover, attenuation of tauroursodeoxycholic acid/Takeda-G-protein-receptor-5 signaling induced endoplasmic reticulum stress, oxidative stress and cell survival genes, but decreased expression of pluripotency genes in parthenogenetically activated embryos cultured under excess glucose conditions. These data suggest that Takeda-G-protein-receptor-5 signaling pathways link the unfolded protein response and genome damage response. Furthermore, this study identifies Takeda-G-protein-receptor-5 signaling as a potential target for mitigating fertility issues caused by nutrient excess-associated blastomere stress and embryo death.
Collapse
Affiliation(s)
- Naomi Dicks
- Department of Animal Science, McGill University, Quebec, Canada
| | | | - Luke Currin
- Department of Animal Science, McGill University, Quebec, Canada
| | | | | | - Rafael G Mondadori
- Department of Animal Science, McGill University, Quebec, Canada
- ReproPel, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Luis B Agellon
- School of Human Nutrition, McGill University, Quebec, Canada
| | | |
Collapse
|
8
|
Paskevicius T, Jung J, Pujol M, Eggleton P, Qin W, Robinson A, Gutowski N, Holley J, Smallwood M, Newcombe J, Zochodne D, Chen XZ, Tang J, Kraus A, Michalak M, Agellon LB. The Fabp5/calnexin complex is a prerequisite for sensitization of mice to experimental autoimmune encephalomyelitis. FASEB J 2020; 34:16662-16675. [PMID: 33124722 DOI: 10.1096/fj.202001539rr] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 10/01/2020] [Accepted: 10/13/2020] [Indexed: 11/11/2022]
Abstract
We previously showed that calnexin (Canx)-deficient mice are desensitized to experimental autoimmune encephalomyelitis (EAE) induction, a model that is frequently used to study inflammatory demyelinating diseases, due to increased resistance of the blood-brain barrier to immune cell transmigration. We also discovered that Fabp5, an abundant cytoplasmic lipid-binding protein found in brain endothelial cells, makes protein-protein contact with the cytoplasmic C-tail domain of Canx. Remarkably, both Canx-deficient and Fabp5-deficient mice commonly manifest resistance to EAE induction. Here, we evaluated the importance of Fabp5/Canx interactions on EAE pathogenesis and on the patency of a model blood-brain barrier to T-cell transcellular migration. The results demonstrate that formation of a complex comprised of Fabp5 and the C-tail domain of Canx dictates the permeability of the model blood-brain barrier to immune cells and is also a prerequisite for EAE pathogenesis.
Collapse
Affiliation(s)
| | - Joanna Jung
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - Myriam Pujol
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - Paul Eggleton
- Department of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Wenying Qin
- National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, China
| | - Alison Robinson
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - Nick Gutowski
- Department of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Janet Holley
- Department of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Miranda Smallwood
- Department of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Jia Newcombe
- NeuroResource, Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Douglas Zochodne
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB, Canada
| | - Xing-Zhen Chen
- National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, China.,Department of Physiology, University of Alberta, Edmonton, AB, Canada
| | - Jingfeng Tang
- National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, China
| | - Allison Kraus
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada.,National "111" Center for Cellular Regulation and Molecular Pharmaceutics, Hubei University of Technology, Wuhan, China
| | - Luis B Agellon
- School of Human Nutrition, McGill University, Ste. Anne de Bellevue, QC, Canada
| |
Collapse
|
9
|
Diazoxide Protects against Myocardial Ischemia/Reperfusion Injury by Moderating ERS via Regulation of the miR-10a/IRE1 Pathway. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:4957238. [PMID: 32963696 PMCID: PMC7495230 DOI: 10.1155/2020/4957238] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 06/16/2020] [Accepted: 07/17/2020] [Indexed: 12/12/2022]
Abstract
Nowadays, reperfusion is still the most effective treatment for ischemic heart disease. However, cardiac reperfusion therapy would lead to reperfusion injury, which may have resulted from endoplasmic reticulum stress (ERS) during reperfusion. Diazoxide (DZ) is a highly selective mitochondrial adenosine triphosphate-sensitive potassium channel opener. Its protective effect on I/R injury has been confirmed in many organs such as the heart and brain. However, the mechanism of its protective effect has not been fully elucidated. MicroRNAs (miRNAs) are widely involved in pathologies of heart disease. In this study, we found that miR-10a expression was highly upregulated in the myocardial I/R groups, and DZ treatment significantly reduced the expression of miR-10a. More importantly, we found that DZ treatment can moderate ERS via regulation of the miR-10a/IRE1 pathway in the I/R and H/R models, thereby protecting myocardial H/R injury.
Collapse
|
10
|
Haram K, Mortensen JH, Myking O, Magann EF, Morrison JC. The Role of Oxidative Stress, Adhesion Molecules and Antioxidants in Preeclampsia. Curr Hypertens Rev 2020; 15:105-112. [PMID: 30663572 DOI: 10.2174/1573402115666190119163942] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 12/19/2018] [Accepted: 01/11/2019] [Indexed: 12/30/2022]
Abstract
Oxidative stress is a consequence of reduction in the antioxidant capacity and excessive production of reactive oxygen and nitrogen species (ROS). Oxidative agents, which are overproduced due to ischemic-reperfusion injury in the placenta, may overwhelm the normal antioxidant activity. This imbalance is a key feature in the pathogenesis of preeclampsia. A decrease in glutathione peroxidase (GPX) activity is associated with the synthesis of vasoconstrictive eicosanoids such as F2-isoprostanes and thromboxane, which are known to be upregulated in preeclampsia. Biochemical markers of lipid peroxidation, such as malondialdehyde and F2-isoprostane in the placenta, are also increased. Adhesion molecules participate in the pathophysiology of preeclampsia by contributing to a reduced invasion by the trophoblast and increased vascular endothelial damage. Superoxide dismutase (SOD), catalase (CAT) and GPX play important roles counteracting oxidative stress. Other antioxidant factors participate in the etiology of preeclampsia. Levels of antioxidants such as Lycopene, Coenzyme 10, as well as some vitamins, are reduced in preeclamptic gestations.
Collapse
Affiliation(s)
- Kjell Haram
- Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway
| | - Jan Helge Mortensen
- Department of Obstetrics and Gynecology, Haukeland University Hospital, Bergen, Norway.,Department of Public Health and Primary Health Care, University of Bergen, Bergen, Norway
| | - Ole Myking
- Department of Internal Medicine, Section of Endocrinology, Haukeland University Hospital, University of Bergen, Bergen, Norway
| | - Everett F Magann
- Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - John C Morrison
- Department of Obstetrics and Gynecology, University of Mississippi Medical Center, Jackson, Mississippi, MS, United States
| |
Collapse
|
11
|
Wang WA, Agellon LB, Michalak M. Organellar Calcium Handling in the Cellular Reticular Network. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a038265. [PMID: 31358518 DOI: 10.1101/cshperspect.a038265] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ca2+ is an important intracellular messenger affecting diverse cellular processes. In eukaryotic cells, Ca2+ is handled by a myriad of Ca2+-binding proteins found in organelles that are organized into the cellular reticular network (CRN). The network is comprised of the endoplasmic reticulum, Golgi apparatus, lysosomes, membranous components of the endocytic and exocytic pathways, peroxisomes, and the nuclear envelope. Membrane contact sites between the different components of the CRN enable the rapid movement of Ca2+, and communication of Ca2+ status, within the network. Ca2+-handling proteins that reside in the CRN facilitate Ca2+ sensing, buffering, and cellular signaling to coordinate the many processes that operate within the cell.
Collapse
Affiliation(s)
- Wen-An Wang
- Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2S7, Canada
| | - Luis B Agellon
- School of Human Nutrition, McGill University, Ste. Anne de Bellevue, Quebec H9X 3V9, Canada
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2S7, Canada
| |
Collapse
|
12
|
Wang WA, Agellon LB, Michalak M. Endoplasmic reticulum calcium dictates the distribution of intracellular unesterified cholesterol. Cell Calcium 2018; 76:116-121. [PMID: 30463032 DOI: 10.1016/j.ceca.2018.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 11/07/2018] [Accepted: 11/07/2018] [Indexed: 01/06/2023]
Abstract
Endoplasmic reticulum (ER) luminal Ca2+ influences many functions of this organelle, notably the synthesis and quality control of proteins and lipids. Cholesterol is an essential component of biological membranes and a precursor for many biologically important signaling molecules. The sterol regulatory element-binding proteins (SREBPs) are key regulators of lipid metabolism. These transcription factors are synthesized as ER membrane-bound precursor proteins that are proteolytically processed in response to cellular cholesterol status. Recently, ER Ca2+ status was shown to be an important determinant of the basal sensitivity of the sterol sensing mechanism inherent to the SREBP processing pathway. This article discusses the emerging relationship between cellular Ca2+ and cholesterol metabolism.
Collapse
Affiliation(s)
- Wen-An Wang
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2S7, Canada
| | - Luis B Agellon
- School of Human Nutrition, McGill University, Ste. Anne de Bellevue, Quebec, H9X 3V9, Canada.
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2S7, Canada.
| |
Collapse
|
13
|
Michalak M, Agellon LB. Stress Coping Strategies in the Heart: An Integrated View. Front Cardiovasc Med 2018; 5:168. [PMID: 30519562 PMCID: PMC6258784 DOI: 10.3389/fcvm.2018.00168] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 11/02/2018] [Indexed: 12/15/2022] Open
Abstract
The heart is made up of an ordered amalgam of cardiac cell types that work together to coordinate four major processes, namely energy production, electrical conductance, mechanical work, and tissue remodeling. Over the last decade, a large body of information has been amassed regarding how different cardiac cell types respond to cellular stress that affect the functionality of their elaborate intracellular membrane networks, the cellular reticular network. In the context of the heart, the manifestations of stress coping strategies likely differ depending on the coping strategy outcomes of the different cardiac cell types, and thus may underlie the development of distinct cardiac disorders. It is not clear whether all cardiac cell types have similar sensitivity to cellular stress, how specific coping response strategies modify their unique roles, and how their metabolic status is communicated to other cells within the heart. Here we discuss our understanding of the roles of specialized cardiac cells that together make the heart function as an organ with the ability to pump blood continuously and follow a regular rhythm.
Collapse
Affiliation(s)
- Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | - Luis B Agellon
- School of Human Nutrition, McGill University, Ste. Anne de Bellevue, QC, Canada
| |
Collapse
|