1
|
Rezaei K, Mastali G, Abbasgholinejad E, Bafrani MA, Shahmohammadi A, Sadri Z, Zahed MA. Cadmium neurotoxicity: Insights into behavioral effect and neurodegenerative diseases. CHEMOSPHERE 2024; 364:143180. [PMID: 39187026 DOI: 10.1016/j.chemosphere.2024.143180] [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: 06/10/2024] [Revised: 08/07/2024] [Accepted: 08/23/2024] [Indexed: 08/28/2024]
Abstract
Cadmium (Cd) induced neurotoxicity has become a growing concern due to its potential adverse effects on the Central Nervous System. Cd is a Heavy Metal (HM) that is released into the environment, through several industrial processes. It poses a risk to the health of the community by polluting air, water, and soil. Cd builds up in the brain and other neural tissues, raising concerns about its effect on the nervous system due to its prolonged biological half-life. Cd can enter into the neurons, hence increasing the production of Reactive Oxygen Species (ROS) in them and impairing their antioxidant defenses. Cd disrupts the Calcium (Ca2+) balance in neurons, affects the function of the mitochondria, and triggers cell death pathways. As a result of these pathways, the path to the development of many neurological diseases affected by environmental factors, especially Cd, such as Alzheimer's Disease (AD) and Amyotrophic Lateral Sclerosis (ALS) is facilitated. There are cognitive deficits associated with long exposure to Cd. Memory disorders are present in both animals and humans. Cd alters the brain's function and performance in critical periods. There are lifelong consequences of Cd exposure during critical brain development stages. The susceptibility to neurotoxic effects is increased by interactions with a variety of risk factors. Cd poses risks to neuronal function and behavior, potentially contributing to neurodegenerative diseases like Parkinson's disease (PD) and AD as well as cognitive issues. This article offers a comprehensive overview of Cd-induced neurotoxicity, encompassing risk assessment, adverse effect levels, and illuminating intricate pathways.
Collapse
Affiliation(s)
- Kimia Rezaei
- Department of Cell and Molecular Sciences, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran.
| | - Ghazaleh Mastali
- Faculty of Biological Sciences, Kharazmi University, Tehran, Iran.
| | - Elham Abbasgholinejad
- Department of Cell and Molecular Sciences, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran.
| | - Melika Arab Bafrani
- Multiple Sclerosis Research Center (MSRC), Tehran University of Medical Sciences, Tehran, Iran.
| | | | - Zahra Sadri
- The Department of Biological Science, Molecular and Cell Biology, Dedman College of Humanities and Sciences Southern Methodist University (SMU), Dallas, TX, USA.
| | | |
Collapse
|
2
|
Wang Q, Liu C. Mitophagy plays a "double-edged sword" role in the radiosensitivity of cancer cells. J Cancer Res Clin Oncol 2024; 150:14. [PMID: 38238458 PMCID: PMC10796536 DOI: 10.1007/s00432-023-05515-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 12/13/2023] [Indexed: 01/22/2024]
Abstract
Mitochondria are organelles with double-membrane structure of inner and outer membrane, which provides main energy support for cell growth and metabolism. Reactive oxygen species (ROS) mainly comes from mitochondrial and can cause irreversible damage to cells under oxidative stress. Thus, mitochondrial homeostasis is the basis for maintaining the normal physiological function of cells and mitophagy plays a pivotal role in the maintenance of mitochondrial homeostasis. At present, to enhance the sensitivity of cancer cells to radiotherapy and chemotherapy by regulating mitochondria has increasingly become a hot spot of cancer therapy. It is particularly important to study the effect of ionizing radiation (IR) on mitochondria and the role of mitophagy in the radiosensitivity of cancer cells. Most of the existing reviews have focused on mitophagy-related molecules or pathways and the impact of mitophagy on diseases. In this review, we mainly focus on discussing the relationship between mitophagy and radiosensitivity of cancer cells around mitochondria and IR.
Collapse
Affiliation(s)
- Qian Wang
- The First School of Clinical Medicine, Lanzhou University, Lanzhou, 730030, Gansu, China
| | - Chengxin Liu
- Shandong Academy of Medical Sciences, Shandong Cancer Hospital and Institute, Shandong First Medical University, Jinan, 250117, Shandong, China.
| |
Collapse
|
3
|
Flori L, Montanaro R, Pagnotta E, Ugolini L, Righetti L, Martelli A, Di Cesare Mannelli L, Ghelardini C, Brancaleone V, Testai L, Calderone V. Erucin Exerts Cardioprotective Effects on Ischemia/Reperfusion Injury through the Modulation of mitoKATP Channels. Biomedicines 2023; 11:3281. [PMID: 38137502 PMCID: PMC10740937 DOI: 10.3390/biomedicines11123281] [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: 11/09/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 12/24/2023] Open
Abstract
Modulation of mitochondrial K channels represents a pharmacological strategy to promote cardioprotective effects. Isothiocyanates emerge as molecules capable of releasing hydrogen sulfide (H2S), an endogenous pleiotropic gasotransmitter responsible for anti-ischemic cardioprotective effects also through the involvement of mitoK channels. Erucin (ERU) is a natural isothiocyanate resulting from the enzymatic hydrolysis of glucosinolates (GSLs) present in Eruca sativa Mill. seeds, an edible plant of the Brassicaceae family. In this experimental work, the specific involvement of mitoKATP channels in the cardioprotective effect induced by ERU was evaluated in detail. An in vivo preclinical model of acute myocardial infarction was reproduced in rats to evaluate the cardioprotective effect of ERU. Diazoxide was used as a reference compound for the modulation of potassium fluxes and 5-hydroxydecanoic acid (5HD) as a selective blocker of KATP channels. Specific investigations on isolated cardiac mitochondria were carried out to evaluate the involvement of mitoKATP channels. The results obtained showed ERU cardioprotective effects against ischemia/reperfusion (I/R) damage through the involvement of mitoKATP channels and the consequent depolarizing effect, which in turn reduced calcium entry and preserved mitochondrial integrity.
Collapse
Affiliation(s)
- Lorenzo Flori
- Department of Pharmacy, University of Pisa, 56120 Pisa, Italy; (L.F.); (A.M.); (V.C.)
| | - Rosangela Montanaro
- Department of Science, University of Basilicata, 85100 Potenza, Italy; (R.M.); (V.B.)
| | - Eleonora Pagnotta
- Research Centre for Cereal and Industrial Crops, CREA—Council for Agricultural Research and Economics, Via di Corticella 133, 40128 Bologna, Italy; (E.P.); (L.U.); (L.R.)
| | - Luisa Ugolini
- Research Centre for Cereal and Industrial Crops, CREA—Council for Agricultural Research and Economics, Via di Corticella 133, 40128 Bologna, Italy; (E.P.); (L.U.); (L.R.)
| | - Laura Righetti
- Research Centre for Cereal and Industrial Crops, CREA—Council for Agricultural Research and Economics, Via di Corticella 133, 40128 Bologna, Italy; (E.P.); (L.U.); (L.R.)
| | - Alma Martelli
- Department of Pharmacy, University of Pisa, 56120 Pisa, Italy; (L.F.); (A.M.); (V.C.)
- Interdepartmental Research Center Nutrafood “Nutraceuticals and Food for Health”, University of Pisa, 56120 Pisa, Italy
- Interdepartmental Research Centre of Ageing Biology and Pathology, University of Pisa, 56120 Pisa, Italy
| | - Lorenzo Di Cesare Mannelli
- Pharmacology and Toxicology Section, Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, 50139 Florence, Italy; (L.D.C.M.); (C.G.)
| | - Carla Ghelardini
- Pharmacology and Toxicology Section, Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, 50139 Florence, Italy; (L.D.C.M.); (C.G.)
| | - Vincenzo Brancaleone
- Department of Science, University of Basilicata, 85100 Potenza, Italy; (R.M.); (V.B.)
| | - Lara Testai
- Department of Pharmacy, University of Pisa, 56120 Pisa, Italy; (L.F.); (A.M.); (V.C.)
- Interdepartmental Research Center Nutrafood “Nutraceuticals and Food for Health”, University of Pisa, 56120 Pisa, Italy
- Interdepartmental Research Centre of Ageing Biology and Pathology, University of Pisa, 56120 Pisa, Italy
| | - Vincenzo Calderone
- Department of Pharmacy, University of Pisa, 56120 Pisa, Italy; (L.F.); (A.M.); (V.C.)
- Interdepartmental Research Center Nutrafood “Nutraceuticals and Food for Health”, University of Pisa, 56120 Pisa, Italy
- Interdepartmental Research Centre of Ageing Biology and Pathology, University of Pisa, 56120 Pisa, Italy
| |
Collapse
|
4
|
Chapa-Dubocq XR, Rodríguez-Graciani KM, Escobales N, Javadov S. Mitochondrial Volume Regulation and Swelling Mechanisms in Cardiomyocytes. Antioxidants (Basel) 2023; 12:1517. [PMID: 37627512 PMCID: PMC10451443 DOI: 10.3390/antiox12081517] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 07/24/2023] [Accepted: 07/26/2023] [Indexed: 08/27/2023] Open
Abstract
Mitochondrion, known as the "powerhouse" of the cell, regulates ion homeostasis, redox state, cell proliferation and differentiation, and lipid synthesis. The inner mitochondrial membrane (IMM) controls mitochondrial metabolism and function. It possesses high levels of proteins that account for ~70% of the membrane mass and are involved in the electron transport chain, oxidative phosphorylation, energy transfer, and ion transport, among others. The mitochondrial matrix volume plays a crucial role in IMM remodeling. Several ion transport mechanisms, particularly K+ and Ca2+, regulate matrix volume. Small increases in matrix volume through IMM alterations can activate mitochondrial respiration, whereas excessive swelling can impair the IMM topology and initiates mitochondria-mediated cell death. The opening of mitochondrial permeability transition pores, the well-characterized phenomenon with unknown molecular identity, in low- and high-conductance modes are involved in physiological and pathological increases of matrix volume. Despite extensive studies, the precise mechanisms underlying changes in matrix volume and IMM structural remodeling in response to energy and oxidative stressors remain unknown. This review summarizes and discusses previous studies on the mechanisms involved in regulating mitochondrial matrix volume, IMM remodeling, and the crosstalk between these processes.
Collapse
Affiliation(s)
| | | | | | - Sabzali Javadov
- Department of Physiology, University of Puerto Rico School of Medicine, San Juan, PR 00936-5067, USA; (X.R.C.-D.); (K.M.R.-G.); (N.E.)
| |
Collapse
|
5
|
Shang Y, Li Z, Cai P, Li W, Xu Y, Zhao Y, Xia S, Shao Q, Wang H. Megamitochondria plasticity: function transition from adaption to disease. Mitochondrion 2023:S1567-7249(23)00053-3. [PMID: 37276954 DOI: 10.1016/j.mito.2023.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/08/2023] [Accepted: 06/02/2023] [Indexed: 06/07/2023]
Abstract
As the cell's energy factory and metabolic hub, mitochondria are critical for ATP synthesis to maintain cellular function. Mitochondria are highly dynamic organelles that continuously undergo fusion and fission to alter their size, shape, and position, with mitochondrial fusion and fission being interdependent to maintain the balance of mitochondrial morphological changes. However, in response to metabolic and functional damage, mitochondria can grow in size, resulting in a form of abnormal mitochondrial morphology known as megamitochondria. Megamitochondria are characterized by their considerably larger size, pale matrix, and marginal cristae structure and have been observed in various human diseases. In energy-intensive cells like hepatocytes or cardiomyocytes, the pathological process can lead to the growth of megamitochondria, which can further cause metabolic disorders, cell damage and aggravates the progression of the disease. Nonetheless, megamitochondria can also form in response to short-term environmental stimulation as a compensatory mechanism to support cell survival. However, extended stimulation can reverse the benefits of megamitochondria leading to adverse effects. In this review, we will focus on the findings of the different roles of megamitochondria, and their link to disease development to identify promising clinical therapeutic targets.
Collapse
Affiliation(s)
- Yuxing Shang
- Reproductive Sciences Institute, Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, PR China
| | - Zhanghui Li
- Reproductive Sciences Institute, Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, PR China
| | - Peiyang Cai
- Reproductive Sciences Institute, Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, PR China
| | - Wuhao Li
- Reproductive Sciences Institute, Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, PR China
| | - Ye Xu
- Reproductive Sciences Institute, Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, PR China
| | - Yangjing Zhao
- Reproductive Sciences Institute, Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, PR China
| | - Sheng Xia
- Reproductive Sciences Institute, Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, PR China
| | - Qixiang Shao
- Reproductive Sciences Institute, Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, PR China; Institute of Medical Genetics and Reproductive Immunity, School of Medical Science and Laboratory Medicine, Jiangsu College of Nursing, Huai'an 223002, Jiangsu, PR China.
| | - Hui Wang
- Reproductive Sciences Institute, Jiangsu Key Laboratory of Medical Science and Laboratory Medicine, Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu, PR China.
| |
Collapse
|
6
|
Swelling and membrane potential dynamics of glial Müller cells. Biosystems 2022; 221:104772. [PMID: 36113739 DOI: 10.1016/j.biosystems.2022.104772] [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: 05/08/2022] [Revised: 08/20/2022] [Accepted: 08/27/2022] [Indexed: 11/21/2022]
Abstract
Presently a detailed biophysical model describing reversible and irreversible swelling dynamics of Müller cells (MC) is reported. The model includes a biophysical block of ionic and neutral species transport via MC membrane, water transport induced by osmotic pressure and pressure generated by membrane deformations, MC membrane potential and membrane mechanical properties. The model describes reversible and irreversible MC swelling (MCS) using the same set of parameters. The model was used in fitting available experimental data, and produced numerical values of previously unknown model parameters, including those describing mechanical properties of Müller cell membrane (MCM) with respect to bending and stretching. Numerical experiments simulating MC swelling showed complex oscillation dynamics of the relevant parameters in physiological initial conditions. In particular, MC membrane potential (ΔΨMC) demonstrated complex oscillation dynamics, which may be described by a superposition of several oscillations with their periods in the milliseconds, 100-ms and seconds time ranges. Dynamics of reversible and irreversible MCS, and the transition criteria from reversible to irreversible MCS modes were determined in model simulations.
Collapse
|
7
|
Khmelinskii I, Makarov VI. Theoretical approaches used in the modelling of reversible and irreversible mitochondrial swelling in vitro. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2022; 172:15-23. [PMID: 35447196 DOI: 10.1016/j.pbiomolbio.2022.04.004] [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: 12/25/2021] [Revised: 03/25/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
Existing theoretical approaches were considered that allow modelling of mitochondrial swelling (MS) dynamics. Simple phenomenological kinetic models were reviewed. Simple and extended biophysical and bioenergetic models that ignore mechanical properties of inner mitochondrial membrane (IMM), and similar models that include these mechanical properties were also reviewed. Limitations of these models we considered, as regards correct modelling of MS dynamics. It was found that simple phenomenological kinetic models have significant limitations, due to dependence of the kinetic parameter values estimated by fitting of the experimental data on the experimental conditions. Additionally, such simple models provide no understanding of the detailed mechanisms behind the MS dynamics, nor of the dynamics of various system parameters during MS. Thus, biophysical and bioenergetic models ignoring IMM mechanical properties can't be used to model the transition between reversible and irreversible MS. However, simple and extended biophysical models that include IMM mechanical properties allow modelling the transition to irreversible swelling. These latter models are still limited due to significantly simplified description of biochemistry, compared to those of bioenergetic models. Finally, a strategy of model development is proposed, towards correct interpretation of the mitochondrial life cycle, including the effects of MS dynamics.
Collapse
Affiliation(s)
- Igor Khmelinskii
- Universidade do Algarve, FCT, DQB and CEOT, 8005-139, Faro, Portugal
| | - Vladimir I Makarov
- University of Puerto Rico, Rio Piedras Campus, PO Box 23343, San Juan, PR, 00931-3343, USA.
| |
Collapse
|
8
|
Khmelinskii I, Makarov V. Theoretical analysis of reversible and irreversible mitochondrial swelling in vivo. Biosystems 2022; 217:104679. [DOI: 10.1016/j.biosystems.2022.104679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 04/06/2022] [Indexed: 11/02/2022]
|
9
|
Khmelinskii I, Makarov VI. Mitochondrial ATP Synthesis Activated by Exciton Energy Transfer from Müller cell Intermediate Filaments. Chem Phys 2022. [DOI: 10.1016/j.chemphys.2022.111475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
10
|
Han L, Zhang Y, Li J, Xiao Y, Lu M, Li Y, Wang M. Phloretin attenuation of hepatic steatosis via an improvement of mitochondrial dysfunction by activating AMPK-dependent signaling pathways in C57BL/6J mice and HepG2 cells. Food Funct 2021; 12:12421-12433. [PMID: 34788781 DOI: 10.1039/d1fo02577e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Phloretin, a dihydrochalcone, widely exists in the fruits of apple trees and crabapple trees (Malus prunifolia) with multiple biological activities. Presently, we studied the function of phloretin on the attenuation of hepatic steatosis and further explored the underlying mechanisms both in vitro and in vivo. Male C57BL/6J mice were fed a normal diet or high fat diet (HFD) with or without phloretin (100 mg kg-1) for 12 weeks. HepG2 cells were induced by 200 μM palmitic acid (PA) and co-incubated with phloretin (50 μM) for 24 h. The results showed that phloretin treatment significantly decreased the accumulation of lipids in the liver of the HFD-fed C57BL/6J mice and PA-induced HepG2 cells. Also, phloretin effectively ameliorated hepatic steatosis via promoting fatty acid β-oxidation (FAO). This biological activity of phloretin was closely related to its capacity to improve mitochondrial dysfunction, including the promotion of mitochondrial biosynthesis and inhibition of mitochondrial swelling through the AMPK-dependent SIRT1/PGC-1α and SIRT3/CypD signaling pathways, respectively. These results demonstrate that phloretin effectively improves mitochondrial function and ameliorates HFD-induced hepatic steatosis through an AMPK-dependent signaling pathway.
Collapse
Affiliation(s)
- Lin Han
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, P. R. China. .,Engineering Technology Research Center of Characteristic Biological Resources in Northeast of Chongqing, Chongqing Three Gorges University, Chongqing 404100, P. R. China
| | - Yao Zhang
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, P. R. China.
| | - Jia Li
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, P. R. China.
| | - Yao Xiao
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, P. R. China.
| | - Mei Lu
- Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA
| | - Yunlong Li
- Institute of Functional Food of Shanxi, Shanxi Agricultural University, Taiyuan, P. R. China
| | - Min Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling 712100, P. R. China.
| |
Collapse
|
11
|
Calsequestrin 1 Is an Active Partner of Stromal Interaction Molecule 2 in Skeletal Muscle. Cells 2021; 10:cells10112821. [PMID: 34831044 PMCID: PMC8616366 DOI: 10.3390/cells10112821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/13/2021] [Accepted: 10/19/2021] [Indexed: 12/25/2022] Open
Abstract
Calsequestrin 1 (CASQ1) in skeletal muscle buffers and senses Ca2+ in the sarcoplasmic reticulum (SR). CASQ1 also regulates store-operated Ca2+ entry (SOCE) by binding to stromal interaction molecule 1 (STIM1). Abnormal SOCE and/or abnormal expression or mutations in CASQ1, STIM1, or STIM2 are associated with human skeletal, cardiac, or smooth muscle diseases. However, the functional relevance of CASQ1 along with STIM2 has not been studied in any tissue, including skeletal muscle. First, in the present study, it was found by biochemical approaches that CASQ1 is bound to STIM2 via its 92 N-terminal amino acids (C1 region). Next, to examine the functional relevance of the CASQ1-STIM2 interaction in skeletal muscle, the full-length wild-type CASQ1 or the C1 region was expressed in mouse primary skeletal myotubes, and the myotubes were examined using single-myotube Ca2+ imaging experiments and transmission electron microscopy observations. The CASQ1-STIM2 interaction via the C1 region decreased SOCE, increased intracellular Ca2+ release for skeletal muscle contraction, and changed intracellular Ca2+ distributions (high Ca2+ in the SR and low Ca2+ in the cytosol were observed). Furthermore, the C1 region itself (which lacks Ca2+-buffering ability but has STIM2-binding ability) decreased the expression of Ca2+-related proteins (canonical-type transient receptor potential cation channel type 6 and calmodulin 1) and induced mitochondrial shape abnormalities. Therefore, in skeletal muscle, CASQ1 plays active roles in Ca2+ movement and distribution by interacting with STIM2 as well as Ca2+ sensing and buffering.
Collapse
|
12
|
Khmelinskii I, Makarov V. Reversible and irreversible mitochondrial swelling: Effects of variable mitochondrial activity. Biosystems 2021; 210:104559. [PMID: 34627969 DOI: 10.1016/j.biosystems.2021.104559] [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: 08/23/2021] [Revised: 10/03/2021] [Accepted: 10/03/2021] [Indexed: 10/20/2022]
Abstract
An extended biophysical model was obtained by upgrading the previously reported one (Khmelinskii and Makarov, 2021). The upgraded model accommodates variations of solute transport rates through the inner mitochondrial membrane (IMM) within the mitochondrial population, described by a Gaussian distribution. However, the model may be used for any functional form of the distribution. The dynamics of system parameters as predicted by the current model differed from that predicted by the previous model in the same initial conditions (Khmelinskii and Makarov, 2021). The amount of change varied from one parameter to the other, remaining in the 1-38% range. The upgraded model fitted the available experimental data with a better accuracy (R = 0.993) compared to the previous model (R = 0.978) using the same experimental data (Khmelinskii and Makarov, 2021). The fitting procedure also estimated the Gaussian distribution parameters. The new model requires much larger computational resources, but given its higher accuracy, it may be used for better analysis of experimental data and for better prediction of MS dynamics in different initial conditions. Note that activities of individual mitochondria in mitochondrial populations should vary within biological tissues. Thus, the currently upgraded model is a better tool for biological and bio-medical applications. We believe that this model is much better adapted to the analysis of MS dynamics in vivo.
Collapse
Affiliation(s)
- Igor Khmelinskii
- Universidade do Algarve, FCT, DQB and CEOT, 8005-139, Faro, Portugal
| | - Vladimir Makarov
- University of Puerto Rico, Rio Piedras Campus, PO Box 23343, San Juan, PR, 00931-3343, USA.
| |
Collapse
|
13
|
Khmelinskii I, Makarov V. Reversible and irreversible mitochondrial swelling in vitro. Biophys Chem 2021; 278:106668. [PMID: 34418677 DOI: 10.1016/j.bpc.2021.106668] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/07/2021] [Accepted: 08/10/2021] [Indexed: 11/18/2022]
Abstract
Mitochondrial activity as regards ATP production strongly depends on mitochondrial swelling (MS) mode. Therefore, this work analyzes reversible and irreversible MS using a detailed biophysical model. The reported model includes mechanical properties of the inner mitochondrial membrane (IMM). The model describes MS dynamics for spherically symmetric, axisymmetric ellipsoidal and general ellipsoidal mitochondria. Mechanical stretching properties of the IMM were described by a second-rank rigidity tensor. The tensor components were estimated by fitting to the earlier reported results of in vitro experiments. The IMM rigidity constant of ca. 0.008 dyn/nm was obtained for linear deformations. The model also included membrane bending effects, which were small compared to those of membrane stretching. The model was also tested by simulation of the earlier reported experimental data and of the system dynamics at different initial conditions, predicting the system behavior. The transition criteria from reversible to irreversible swelling were determined and tested. The presently developed model is applicable directly to the analysis of in vitro experimental data, while additional improvements are necessary before it could be used to describe mitochondrial swelling in vivo. The reported theoretical model also provides an idea of physically consistent mechanism for the permeability transport pore (PTP) opening, which depends on the IMM stretching stress. In the current study, this idea is discussed briefly, but a detailed theoretical analysis of these ideas will be performed later. The currently developed model provides new understanding of the detailed MS mechanism and of the conditions for the transition between reversible and irreversible MS modes. On the other hand, the current model provides useful mathematical tools, that may be successfully used in mitochondrial biophysics research, and also in other applications, predicting the behavior of mitochondria in different conditions of the surrounding media in vitro or cellular cyto(sarco)plasm in vivo. These mathematical tools are based on real biophysical processes occurring in mitochondria. Thus, we note a significant progress in the theoretical approach, which may be used in real biological systems, compared to the earlier reported models. Significance of this study derives from inclusion of IMM mechanical properties, which directly impact the reversible and irreversible mitochondrial swelling dynamics. Reversible swelling corresponds to reversible IMM deformations, while irreversible swelling corresponds to irreversible deformations, with eventual membrane disruption. The IMM mechanical properties are directly dependent on the membrane biochemical composition and structure. The IMM deformationas are induced by osmotic pressure created by the ionic/neutral solute imbalance between the mitochondrial matrix media and the bulk solution in vitro, or cyto(sarco)plasm in vivo. The novelty of the reported model is in the biophysical mechanism detailing ionic and neutral solute transport for a large number of solutes, which were not taken into account in the earlier reported biophysical models of MS. Therefore, the reported model allows understanding response of mitochondria to the changes of initial concentration(s) of any of the solute(s) included in the model. Note that the values of all of the model parameters and kinetic constants have been estimated and the resulting complete model may be used for quantitative analysis of mitochondrial swelling dynamics in conditions of real in vitro experiments.
Collapse
Affiliation(s)
- Igor Khmelinskii
- Universidade do Algarve, FCT, DQB and CEOT, 8005-139 Faro, Portugal
| | - Vladimir Makarov
- University of Puerto Rico, Rio Piedras Campus, PO Box 23343, San Juan, PR 00931-3343, USA.
| |
Collapse
|
14
|
Khmelinskii I, Makarov V. Stretching tension effects in permeability transition pores of inner mitochondrial membrane. Biosystems 2021; 208:104488. [PMID: 34274463 DOI: 10.1016/j.biosystems.2021.104488] [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: 06/11/2021] [Revised: 07/11/2021] [Accepted: 07/12/2021] [Indexed: 11/30/2022]
Abstract
Presently a mechanism of permeability transition pore (PTP) opening was proposed and discussed. This mechanism is based on mechanical stretching of inner mitochondrial membrane (IMM) caused by mitochondrial swelling (MS). The latter is induced by osmotic pressure generated by solute imbalance between the matrix and the surrounding cyto(sarco)plasm. Modelled by the Monte-Carlo method, an IMM fragment of 350 simulated biological molecules exhibited formation of micro-domains containing two protein and seven phospholipid molecules. The energies (-0.191 eV per molecule) in these micro-domains were significantly larger than those (-0.375 eV per molecule) of other parts of the IMM fragment. Stretching forces applied to such domains expanded them much more than other parts of the IMM fragment. We identify these micro-domains as the PTPs. Both linear and nonlinear functions were used for the strain-stress relation of the IMM fragment, with nonlinear effects more important at large IMM stretching strains. Thus, two main factors are incorporated into the PTP opening mechanism: (1) presence of micro-domains in the IMM structure and (2) IMM stretching stress caused by MS. Taking into account both of these factors, the equation for the probability of PTP opening was deduced, with matrix Ca2+ and H+ ionic concentrations as its parameters. Note that the equation deduced was similar to an earlier reported empirical equation describing PTP opening dynamics. This correspondence provides support to the presently proposed mechanism. Thus, a new look at the PTP opening mechanism is provided, of interest to various research areas related to mitochondrial biophysics.
Collapse
Affiliation(s)
- Igor Khmelinskii
- Universidade do Algarve, FCT, DQB and CEOT, 8005-139, Faro, Portugal
| | - Vladimir Makarov
- University of Puerto Rico, Rio Piedras Campus, PO Box 23343, San Juan, PR, 00931-3343, USA.
| |
Collapse
|
15
|
Mitochondrial osmoregulation in evolution, cation transport and metabolism. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2021; 1862:148368. [PMID: 33422486 DOI: 10.1016/j.bbabio.2021.148368] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 12/22/2020] [Accepted: 01/04/2021] [Indexed: 11/24/2022]
Abstract
This review provides a retrospective on the role of osmotic regulation in the process of eukaryogenesis. Specifically, it focuses on the adjustments which must have been made by the original colonizing α-proteobacteria that led to the evolution of modern mitochondria. We focus on the cations that are fundamentally involved in volume determination and cellular metabolism and define the transporter landscape in relation to these ions in mitochondria as we know today. We provide analysis on how the cations interplay and together maintain osmotic balance that allows for effective ATP synthesis in the organelle.
Collapse
|
16
|
Khmelinskii I, Makarov VI. On the Effects of Mechanical Stress of Biological Membranes in Modeling of Swelling Dynamics of Biological Systems. Sci Rep 2020; 10:8395. [PMID: 32439841 PMCID: PMC7242427 DOI: 10.1038/s41598-020-65217-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 04/20/2020] [Indexed: 11/23/2022] Open
Abstract
We highlight mechanical stretching and bending of membranes and the importance of membrane deformations in the analysis of swelling dynamics of biological systems, including cells and subcellular organelles. Membrane deformation upon swelling generates tensile stress and internal pressure, contributing to volume changes in biological systems. Therefore, in addition to physical (internal/external) and chemical factors, mechanical properties of the membranes should be considered in modeling analysis of cellular swelling. Here we describe an approach that considers mechanical properties of the membranes in the analysis of swelling dynamics of biological systems. This approach includes membrane bending and stretching deformations into the model, producing a more realistic description of swelling. We also discuss the effects of membrane stretching on swelling dynamics. We report that additional pressure generated by membrane bending is negligible, compared to pressures generated by membrane stretching, when both membrane surface area and volume are variable parameters. Note that bending deformations are reversible, while stretching deformation may be irreversible, leading to membrane disruption when they exceed a certain threshold level. Therefore, bending deformations need only be considered in reversible physiological swelling, whereas stretching deformations should also be considered in pathological irreversible swelling. Thus, the currently proposed approach may be used to develop a detailed biophysical model describing the transition from physiological to pathological swelling mode.
Collapse
Affiliation(s)
- Igor Khmelinskii
- Faculty of Science and Technology, Department of Chemistry and Pharmacy, and Center of Electronics, Optoelectronics, and Telecommunications, University of Algarve, Faro, Portugal
| | - Vladimir I Makarov
- Department of Physics, University of Puerto Rico, Rio Piedras Campus, San Juan, USA.
| |
Collapse
|