Abstract
Graphical abstract
Experimental Myocardial infarction (MI) using ligation procedure induces cardiac dysfunction, high level of ROS, inflammation, apoptosis, fibrosis and cardiomyocyte (CM) loss. AAV overexpressing human Trx-2, specifically in CM mitochondria improves mouse cardiac function, reduces the size of cardiac infarct, increases the expression of cardiac anti-inflammatory markers, reduces apoptosis and oxidative stress. However, it does not increase CM proliferation.
Abstract
Introduction and objective
Myocardial infarction (MI), which in general results from complications of atherosclerosis, is characterized by high inflammation and cardiomyocytes (CMs) apoptosis and by major loss of CMs. Regeneration of these lost CMs represents a major challenge for MI therapy. The increase of mitochondrial reactive oxygen species (ROS) is involved in cell cycle arrest which can be restarted by hypoxia or in the presence of ROS scavengers. Among ROS scavengers, mitochondrial thioredoxin 2 (Trx-2), an important antioxidant protein, could play a role in the CMs renewal.
Method
In this study, we investigated the effect of Trx-2 on mouse heart after an experimental MI.
Results
Trx-2 improves mouse cardiac function, reduces cardiac infarction size and increases the expression of cardiac anti-inflammatory markers. In addition, it reduces apoptosis and oxidative stress in heart tissue of mice after MI but it does not increase CM proliferation in cell culture or in heart tissue.
Conclusion
Mitochondrial Trx-2 effectively protects against heart infarction, likely via the reduction of oxidative stress, inflammation and apoptosis but not through CM renewal.
Significance statement
The current study unveils the complexities of MI and highlights mitochondrial Trx-2 role. Post-MI, marked by inflammation, CM apoptosis and significant CM loss. Trx-2 emerges as a vital protector. Its intervention improves mouse cardiac function, reduces infarction size and fosters an anti-inflammatory environment. By uncovering these mechanisms, the study suggests potential therapeutic strategies for oxidative stress, inflammation and apoptosis in MI, positioning Trx-2 as a promising candidate for future cardiac interventions.
Introduction
Myocardial infarction (MI) remains a significant cause of mortality, especially among the elderly (Saleh & Ambrose 2018). The majority of MI results from the complications of atherosclerosis which is characterized by inflammation of the arterial wall. The inflammatory process plays a key role in all stages of atherosclerosis (Libby 2002). Several studies demonstrated the role of activated macrophages and activated T lymphocytes in atheroma plaque destabilization (Libby 2002, Hansson 2005). The combination of macrophages and lymphocytes in vulnerable plaque is associated with the secretion of cytokines and lytic enzymes that result in thinning of the fibrous cap, predisposing lesions to rupture (Libby 2002, Hansson 2005). Moreover, one of the defining features of MI is the substantial loss of cardiomyocytes (CMs) following cardiac injury. Consequently, the regeneration of these lost CMs remains a paramount challenge in the pursuit of effective therapies for MI. Recent studies have indicated that the mammalian neonatal heart has a regenerative capacity of 7 days postnatally (Porrello et al. 2011). During this period, the neonatal heart is in an oxygen-rich environment that leads to a metabolic change and enhance mitochondrial reactive oxygen species (ROS) generation, oxidative DNA damage and DNA damage response (DDR) markers. These events lead to arrest of the CM cell cycle. However, the cell cycle can restart in hypoxia or in the presence of ROS scavengers (Puente et al. 2014). Among ROS scavengers, the thioredoxin 2 (Trx-2) could play a role in the CM cell cycle restart.
Trx-2 is a mitochondrial redox protein containing the active-site Cys32-Gly-Pro-Cys35. It is encoded by a nuclear gene, Trx-2, with a mitochondrial targeting signal peptide. Initially, Trx-2 was cloned from a rat heart library by Spyrou et al. (Spyrou et al. 1997). Subsequently, Trx-2 also has been cloned from human osteosarcoma cells (Damdimopoulos et al. 2002) and human embryonal stem cells (Chen et al. 2002). The Trx-2 gene is expressed in virtually all organs and tissues with the highest expression level in metabolically active tissues such as the heart (Huang et al. 2015) and the brain (Rybnikova et al. 2000, Kalinina et al. 2008). Trx-2 plays important roles during embryonic development, as early embryonic lethality was seen in the Trx-2–/– homozygous embryos (Nonn et al. 2003). Furthermore, overexpression of Trx-2 can facilitate the development of resistance to ROS-induced apoptosis (Chen et al. 2002). The Trx-2 system appears to have a more important role in preventing mitochondrial dysfunction than the mitochondrial GSH system in endothelial cells under conditions that mimic a septic insult (Lowes & Galley 2011). This is because inhibition of Trx-2 resulted in a higher mitochondrial metabolic activity, lower ATP/ADP ratios, lower oxygen consumption, increased lactate formation and caspase 3 and 7 activation (Lowes & Galley 2011). Trx-2 is important for cell viability and prevents apoptosis-induced cell death, since its knockdown in endothelial cells increases tumor necrosis factor (TNF)/apoptosis signal-regulated kinase 1 (ASK-1)-induced cytochrome c release and cell death (Zhang et al. 2004). Moreover, Trx-2 improves endothelial cell function and reduces atherosclerotic lesions in the apolipoprotein E-deficient mouse model via reducing oxidative stress and increasing NO bioavailability (Zhang et al. 2007). Among other isoforms of Trx, thioredoxin 1 (Trx-1) is mainly cytoplasmic (Holmgren 1985, Lu & Holmgren 2014) and thioredoxin 3 (Trx-3) is highly expressed in spermatozoa and intestinal cells (Jiménez-Hidalgo et al. 2014, p. 3). Since the mitochondrion is the major physiological source of ROS generated during respiration, we here investigate the effect of mitochondrial Trx-2 on the murine heart after an experimental MI.
Materials and methods
In vitro study on neonatal mouse cardiomyocytes
In this study, neonatal mouse CMs were treated with AAV-Luc or AAV-Trx-2 for 48 h. Cell proliferation was measured by EdU labeling with Click-iT EdU Imaging Kit with Alexa Fluor™ 488 (Thermo Fisher Scientific) and ROS assessment was by detecting DHE and derived oxidation products (EOH and ethidium) by HPLC (see Supplementary Methods for details, see section on supplementary materials given at the end of this article).
In vivo study on C57BL/6JRj mice with an experimental MI
The details of all methods and primers used are in the ‘Supplementary Methods’ and ‘Supplementary Table 1’ respectively.
In vivo studies were performed on C57BL/6JRj mice of 8 weeks’ age. Adult male mice were treated or not with AAV-Luciferase or AAV-Trx-2 1 month before an experimental MI. One day before treatment and three weeks after MI, different cardiac parameters were measured by echocardiography. Hearts were harvested, frozen or fixed. Infarction size and fibrosis areas were quantified on heart sections with trichrome stain (Abcam) and Picro-Sirius Red stain Kit (Abcam), respectively (Supplementary Methods). Representative inflammatory and anti-inflammatory markers such as arginase 1, CD206, MCP-1, IL-10 and TGF-β were evaluated at the mRNA level by qPCR (Table 1, Supplementary Methods). For apoptosis, DNA fragmentation was detected in heart sections with the TUNEL Assay Kit − BrdU Red (Abcam) (Supplementary Methods). Aliquots of heart cell lysates were also used to perform Western immunoblots with specific antibodies to Bax and Bcl-2 (Proteintech, France) (Supplementary Methods). Trx-2 effects on oxidative stress in murine hearts was evaluated by the assessment of the amount of DHE reactive ROS (Invitrogen). Cell proliferation was determined through quantification of mononucleated CMs in heart tissue (Supplementary Methods). Data are presented as mean ± s.e.m. All procedures involving animal handling and their care were in accordance with the French Ethic Committee CEEA (Comité d’Ethique en Expérimentation Animale) (authorization: APAFIS#24071-2020020611035354 v4).
Statistical analysis
Statistical analysis was performed using GraphPad Prism 9 software. Unpaired two-tailed Student’s t-test was used for comparison of two different groups (AAV-Luc vs AAV-Trx-2). Statistical significance was considered to be * P < 0.01.
Results
Adeno-associated virus validation
The infection efficiency of AAV-Trx-2 was verified at the mRNA and protein levels in CMs of mouse heart. The results indicated that CMs infected with the AAV-Trx-2 expressed high levels of the Trx-2 gene at the mRNA (1477.55 ± 3.20 vs 12.34 ± 4.50) (Fig. 1B) and at the protein levels (Fig. 1C).
AAV overexpression validation at mRNA and protein levels in mice with MI and in CMs in culture. (A) Representative scheme of plasmid pTR-ETG used for the AAV constructions. (B and C) 8-week-old mice were treated with AAV-Luciferase or AAV-Trx-2 1 month before the MI. (B) mRNA was isolated from mice heart tissue and the mRNA of Trx-2 was quantified by Q-PCR and normalized against 36B4 housekeeping gene. (C) Total mice cardiac protein was used and a western blot was realized using a specific antibody against human Trx-2. Recombinant human (rh) Trx-2 was loaded as control.
Citation: Redox Experimental Medicine 2024, 1; 10.1530/REM-23-0029
Trx-2 improves mouse cardiac functions and remodeling after experimental MI
Figure 2 shows the echocardiography of the left ventricle in diastole and systole (Fig. 2A). It also shows a significant increase of the percentage of left ventricular ejection fraction (LVEF) in infarcted mice infected with the AAV-Trx-2 in comparison to MI mice infected with the AAV-Luciferase (62.38 ± 2.11 vs 44.99 ± 2.47; P < 0.0001) (Fig. 2B). Similarly, a significant increase of the percentage of the relative parietal thickness (0.30 ± 0.007 vs 0.23 ± 0.008, P < 0.0001) (Fig. 2C), the interventricular septum thickness (0.095 ± 0.002 vs 0.073 ± 0.003, P = 0.0003) (Fig. 2D) and the posterior wall thickness (0.064 ± 0.002 vs 0.053 ± 0.001, P = 0.0009) (Fig. 2E) was observed in the same experimental conditions. Although, the left ventricular diameter was significantly reduced when infracted mice were treated with AAV-Trx-2 (0.29 ± 0.008 vs 0.37 ± 0.015, P < 0.0001) (Fig. 2F).
Trx-2 improves cardiac functions and cardiac remodeling after MI. Quantification of cardiac parameters of 8-week-old mice treated with AAV-Trx-2 1 month before MI. (A) Echocardiography M-mode of the left ventricle in diastole and systole. (B) Quantification of the % of left ventricular ejection fraction (LVEF). (C) Quantification of the relative parietal thickness. (D) Quantification of the interventricular septum thickness. (E) Quantification of the posterior wall thickness. (F) Quantification of the left ventricular diameter 3 weeks after experimental myocardial infarction. SHAM (n = 11), luciferase (n = 18) and Trx-2 (n = 18). For all panels: ***P < 0.0005 and ****P = 0.0001. Data are presented as mean ± s.e.m. Mann–Whitney test was used to compare AAV-Trx-2 vs AAV-Luciferase.
Citation: Redox Experimental Medicine 2024, 1; 10.1530/REM-23-0029
Trx-2 reduces cardiac infarcted size after experimental MI in mice
Next, we showed in mice with experimental MI that AAV-Trx-2 infection strongly and significantly reduced the size of the infarcted area in comparison to control (10.27 ± 3.49 vs 41.74 ± 2.69, P = 0.0003) (Fig. 3A represents images of infarcted area and Fig. 3B represents the % of infarcted size).
Trx-2 decreases infarction size after MI. Quantification of infarcted area on heart sections of 8-week-old mice treated with AAV-Trx-2 1 month before MI. (A) Representative images of trichrome staining on heart sections. (B) Quantification of infarct size on heart sections with trichrome staining. Luciferase (n = 9) and Trx-2 (n = 8). ** *P < 0.0005. Data are presented as mean ± s.e.m. Mann–Whitney test was used to compare AAV-Trx-2 vs AAV-Luciferase.
Citation: Redox Experimental Medicine 2024, 1; 10.1530/REM-23-0029
Trx-2 increases cardiac anti-inflammatory markers after experimental MI in mice
We measured the expression levels of representative anti-inflammatory markers in heart tissues of mice with experimental MI that had been treated with AAV-Trx-2. These included arginase 1, CD206, IL-10 and TGF-β. Figure 4 shows a significant increase of the mRNA level of all markers with AAV-Trx-2 in comparison to AAV-Luciferase (1.33 ± 0.18 vs 1.00 ± 0.03, P = 0.03 for arginase; 1.37 ± 0.09 vs 1.00 ± 0.02, P < 0.0001 for CD206; 2.64 ± 0.67 vs 0.98 ± 0.02, P = 0.0004 for IL-10; and 1.47 ± 0.04 vs 0.99 ± 0.01, P < 0.0001 for TGF-β).
Trx-2 increases anti-inflammatory markers in tissue heart after experimental MI in mice. Evaluation, at the mRNA level, of representative inflammatory markers in heart of 8-week-old mice treated with AAV-Luciferase and AAV-Trx-2 1 month before MI. mRNA quantification of arginase 1, CD206, IL-10 and TGF-β in heart tissue of mice with experimental MI. Luciferase (n = 9) and Trx-2 (n = 6). *P < 0.05, ***P < 0.0005 and ****P < 0.0001. Data are presented as mean ± s.e.m. Mann–Whitney test was used to compare AAV-Trx-2 vs AAV-Luciferase.
Citation: Redox Experimental Medicine 2024, 1; 10.1530/REM-23-0029
AAV-Trx-2 reduces apoptosis in heart tissue after experimental MI in mice
Beside the effect of Trx-2 on anti-inflammatory marker expression, we also found that AAV-Trx-2 significantly reduced apoptosis when using the TUNEL approach (13.93 ± 0.10% vs 31.60 ± 1.52% for control, P = 0.05) (Fig. 5, panel A). Similar effects of Trx-2 were also observed on Bcl-2 and Bax protein expression. Trx-2 significantly increases the protein expression of Bcl-2 (anti-apoptotic) (0.98 ± 0.04 vs 0.68 ± 0.04, P = 0.0079) and significantly decreases the protein expression of Bax (pro-apoptotic) (0.72 ± 0.05 vs 1.11 ± 0.04, P = 0.0079) in heart tissue of experimental MI mice. Thus, the Bax/Bcl-2 ratio is significantly reduced (0.73 ± 0.05 vs 1.66 ± 0.17, P = 0.0079) (Fig. 5B).
Trx-2 reduces apoptosis in heart tissue after experimental MI in mice. Analysis of apoptosis markers at the proteins level of 8-week-old mice treated with AAV-Luciferase and AAV-Trx-2 1 month before MI. (A) Bcl-2 protein expression level in myocardial tissues. (B) Bax protein expression level in myocardial tissues. (C) Quantification of the ratio of Bax/Bcl-2 in myocardial tissues. (D) TUNEL assay quantification with cTnT staining in green, TUNEL staining in red and DAPI in blue (n = 5). For all panels: *P < 0.05 and **P < 0.005. Data are presented as mean ± s.e.m. Mann–Whitney test was used to compare AAV-Trx-2 vs AAV-Luciferase.
Citation: Redox Experimental Medicine 2024, 1; 10.1530/REM-23-0029
AAV-Trx-2 reduces oxidative stress in mouse CMs in culture and in heart tissue after experimental MI in mice
Mice with experimental MI treated with AAV-Trx-2 strongly and significantly reduced dihydroethidium (DHE) (1.97 ± 0.29 vs 7.05 ± 0.16 DHE mean intensity, P = 0.0022) (Fig. 6A). Of note, measurement of DHE is a mean to quantify total ROS. Similarly, treatment of cultured CMs with AAV-Trx-2 significantly reduced ethidium, a reduced product of DHE that quantifies H2O2 and other ROS, in CMs in the basal state (5.0 ± 1.00 vs 24.00 ± 1.47, P = 0.02) and when CMs are treated with H2O2 (6.5 ± 1.3 vs 35.6 ± 2.9). Interestingly, AAV-Trx-2 does not reduce EOH, another reduced product of DHE that quantifies superoxide, in CMs in basal state or treated with H2O2 (Fig. 6B).
Trx-2 reduces oxidative stress in murine CMs in culture and in mice after MI. Analysis of the oxidative state on heart sections of 8-week-old mice treated with AAV-Luciferase and AAV-Trx-2 1 month before MI, and on neonatal murine CMs treated with AAV-Luciferase and AAV-Trx-2 for 48 h. (A) Representative images of dihydroethidium (DHE) staining in red on heart sections and quantification of DHE intensity in mice SHAM or treated with AAV-Luciferase or AAV-Trx-2 (n = 6). (B) Quantification of EOH and ethidium by HPLC in CMs treated with DHE (n = 3). For all panels: *P < 0.05 and **P < 0.005. Data are presented as mean ± s.e. m. Mann–Whitney test was used to compare AAV-Trx-2 vs AAV-Luciferase.
Citation: Redox Experimental Medicine 2024, 1; 10.1530/REM-23-0029
AAV-Trx-2 does not increase CM proliferation in cell culture and in heart tissue after experimental MI in mice
Since oxidative stress was suggested to be involved in CM cell cycle arrest (Puente et al. 2014), the reduction of oxidative stress should induce CM proliferation. Thus, we focused on the effect of AAV-Trx-2 on CM proliferation in cell culture and in mice with MI. Figure 7A shows that AAV-Trx-2 does not induce CM proliferation in culture (3.49 ± 0.59% EdU-positive cells vs 3.90 ± 0.83% for the control, P = 0.7). In addition, we evaluated the number of mononucleated CMs in culture and in heart tissue treated or not with AAV-Trx-2. Indeed, CMs in adult heart are reported to be mainly at a binucleated state (Paradis et al. 2014). Binucleation is a characteristic of terminally differentiated cells that are unable to proliferate, whereas mononucleated cells continue to cycle (Paradis et al. 2014). Figure 7B shows that AAV-Trx-2 does not increase the number of mononucleated cells (9.5 ± 1.09 vs 10.47 ± 0.86 for the control, P = 0.7). Moreover, we studied the effect of AAV-Trx-2 on the expression of p16 and p21, two cyclin-dependent kinase inhibitors (Aprelikova et al. 1995), at the mRNA level on heart tissue of experimental MI mice treated or not with AAV-Trx-2. Figure 7C shows a significant reduction of mRNA level of p16 (0.67 ± 0.09 vs 1.00 ± 0.02, P = 0.001) and Fig. 7D shows there is also a reduction of the mRNA level of p21 without however being significance (0.87 ± 0.06 vs 0.99 ± 0.02, P = 0.23).
Trx-2 does not induce cell proliferation in neonatal murine CMs in culture but decreases p16 levels in mice after MI. Analysis of the cell proliferation on neonatal murine CMs treated with AAV-Luciferase and AAV-Trx-2 for 24 h. (A) EdU labeling images and quantification with cTnT in red, EdU in green and DAPI in blue (n = 3). (B) Quantification of % mononucleated CMs on heart sections by immunostaining of CMs with cTNT and DAPI labeling (n = 3). (C and D) mRNA quantification of p16 and p21 in infarcted heart mice treated with AAV-Luciferase and AAV-Trx-2. Luciferase (n = 9) and Trx-2 (n = 6). **P < 0.005. Data are presented as mean ± s.e.m. Mann–Whitney test was used to compare AAV-Trx-2 vs AAV-Luciferase.
Citation: Redox Experimental Medicine 2024, 1; 10.1530/REM-23-0029
Discussion
Increasing evidence suggests that risk factors for atherosclerosis can lead to dramatic increase in the concentration of ROS in the vascular wall contributing to endothelium damage, oxidized low-density lipoproteins (oxLDLs) generation and stimulation of atherosclerotic mediators leading to atheroma plaque rupture and MI (Madamanchi et al. 2005). The consequence of the latter event is a major loss of CMs.
In this study, we investigated, on the one hand, the impact of elevated Trx-2, a specific mitochondrial antioxidant, on heart functions, inflammation, CMs apoptosis and heart infarction size in mice with experimental MI. On the other hand, we studied the role of Trx-2 on CM proliferation. Indeed, the renewal of adult heart tissue in CMs after injury is very weak. Thus, regeneration of the myocardium is crucial. Several therapeutic approaches have shown disappointing results (Orlic et al. 2001, Balsam et al. 2004, Murry et al. 2004, Menasché et al. 2008). Interestingly, lower vertebrates and neonatal mammals are able to regenerate their myocardium spontaneously 7 days after birth (Porrello et al. 2011, 2013, Gemberling et al. 2015, Polizzotti et al. 2015), but this phenomenon does not occur in adult mammalian hearts. Several ROS, oxidative DNA damage and DDR markers have been reported to increase in the heart during the first postnatal week. Because high levels of ROS can be found in mitochondria and because ROS scavenging prolongs the postnatal proliferative window of CMs (Puente et al. 2014, Nakada et al. 2017), the idea of a possible link between an environment rich in oxygen and the arrest of the cell cycle of CMs has gained ground.
Trx-2 plays an essential role both in vivo and in vitro. Thus, its inhibition impairs mitochondrial respiratory function and induces cardiac hypertrophy (Hu et al. 2018). In addition, intramyocardial injection of Trx-2 expressing lentiviruses attenuates myocardial ischemia–reperfusion injury in rats (Li et al. 2017b ). In cultured CMs, Trx-2 protects cells from glucose and oxygen deprivation during reperfusion by inhibiting apoptosis (Li et al. 2017c ). In H9c2 cells, it also provides protection against mitochondrial oxidative stress and hyperglycemia-induced myocardial hypertrophy (Li et al. 2017a ). Moreover, in this current study, Trx-2 significantly improved mouse cardiac functions (Fig. 2). It played an important role in cardiac remodeling by reducing cardiac infarction size (Fig. 3A and B), in inflammation by increasing anti-inflammatory markers (Fig. 4) and in apoptosis by reducing apoptosis (Fig. 5). Taken together, these results clearly indicate that Trx-2 provides protection against MI. In addition, Trx-2 strongly and significantly reduces the level of ROS in cultured CMs as well as in mice with experimental MI (Fig. 6A and B). The latter result should be a trigger for the proliferation of adult CMs after injury. Unfortunately, we did not observe any induction of CM proliferation. Indeed, there was no increase in the incorporation of Edu (Fig. 7A) nor increase in the number of mononuclear cells (Fig. 7B) and no change in the expression of p21 (7D). However, we observed a significant decrease of p16 mRNA abundance (7C). Taken together, these results indicated that Trx-2 improves cardiac function through reduction of oxidative stress, inflammation and apoptosis but not through CM renewal. This later result is not expected. Indeed, mitochondrial ROS are involved in several deleterious reactions for the heart including by their effect on cell cycle arrest of CMs (Puente et al. 2014). By reducing mitochondrial ROS, the Trx-2 is expected to induce cell cycle restart. However, this apparent contradiction could be explained by either the fact that the level of ROS is not sufficiently reduced by Trx-2 to induce CMs proliferation or by the fact that the reduction of ROS in mitochondria does not have the same impact that the reduction of ROS in cytosol or nucleus. Indeed, we have recently shown that a Trx-1 mimetic peptide is able to significantly reduce the ROS levels in nucleus and cytosol. As a consequence, it induces cell cycle restart of CMs (Medali et al. 2024).
In conclusion, the findings indicate that Trx-2 administration demonstrates significant improvements in cardiac functions by reducing infarct size, inflammation and apoptosis. This establishes it as a protective factor against MI. Contrary to expectations, Trx-2 fails to induce CMs proliferation, suggesting potential limitations in its ability to trigger this regenerative process. This unexpected outcome may stem from insufficient reduction of ROS levels or a different impact of reducing ROS in mitochondria as compared to other cellular compartments. While Trx-2 did not induce CMs proliferation, its ability to modulate key factors implicated in post-MI recovery positions it as a promising therapeutic candidate for mitigating the adverse effects of MI.
Supplementary materials
This is linked to the online version of the paper at https://doi.org/10.1530/REM-23-0029.
Declaration of interest
The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the study reported.
Funding
This work was supported by Leducq Foundation and by grant to TM from Fonds Marion Elizabeth Brancher.
Acknowledgements
The authors thank Prof. Miguel Torres and Prof. Roger Hajjar for the AAV generation and Dr Margaret Ahmad for proofreading the manuscript.
References
Aprelikova O, Xiong Y & & Liu ET 1995 Both p16 and p21 families of cyclin-dependent kinase (CDK) inhibitors block the phosphorylation of cyclin-dependent kinases by the CDK-activating kinase. Journal of Biological Chemistry 270 18195–18197. (https://doi.org/10.1074/jbc.270.31.18195)
Balsam LB, Wagers AJ, Christensen JL, Kofidis T, Weissman IL & & Robbins RC 2004 Haematopoietic stem cells adopt mature haematopoietic fates in ischaemic myocardium. Nature 428 668–673. (https://doi.org/10.1038/nature02460)
Chen Y, Cai J, Murphy TJ & & Jones DP 2002 Overexpressed human mitochondrial thioredoxin confers resistance to oxidant-induced apoptosis in human osteosarcoma cells. Journal of Biological Chemistry 277 33242–33248. (https://doi.org/10.1074/jbc.M202026200)
Damdimopoulos AE, Miranda-Vizuete A, Pelto-Huikko M, Gustafsson JA & & Spyrou G 2002 Human mitochondrial thioredoxin. Involvement in mitochondrial membrane potential and cell death. Journal of Biological Chemistry 277 33249–33257. (https://doi.org/10.1074/jbc.M203036200)
Gemberling M, Karra R, Dickson AL & & Poss KD 2015 Nrg1 is an injury-induced cardiomyocyte mitogen for the endogenous heart regeneration program in zebrafish. eLife 4 e05871. (https://doi.org/10.7554/eLife.05871)
Hansson GK 2005 Inflammation, atherosclerosis, and coronary artery disease. New England Journal of Medicine 352 1685–1695. (https://doi.org/10.1056/NEJMra043430)
Holmgren A 1985 Thioredoxin. Annual Review of Biochemistry 54 237–271. (https://doi.org/10.1146/annurev.bi.54.070185.001321)
Hu C, Zhang H, Qiao Z, Wang Y, Zhang P & & Yang D 2018 Loss of thioredoxin 2 alters mitochondrial respiratory function and induces cardiomyocyte hypertrophy. Experimental Cell Research 372 61–72. (https://doi.org/10.1016/j.yexcr.2018.09.010)
Huang Q, Zhou HJ, Zhang H, Huang Y, Hinojosa-Kirschenbaum F, Fan P, Yao L, Belardinelli L, Tellides G, Giordano FJ, et al.2015 Thioredoxin-2 inhibits mitochondrial reactive oxygen species generation and apoptosis stress Kinase-1 activity to maintain cardiac function. Circulation 131 1082–1097. (https://doi.org/10.1161/CIRCULATIONAHA.114.012725)
Jiménez-Hidalgo M, Kurz CL, Pedrajas JR, Naranjo-Galindo FJ, González-Barrios M, Cabello J, Sáez AG, Lozano E, Button EL, Veal EA, et al.2014 Functional characterization of thioredoxin 3 (TRX-3), a Caenorhabditis elegans intestine-specific thioredoxin. Free Radical Biology and Medicine 68 205–219. (https://doi.org/10.1016/j.freeradbiomed.2013.11.023)
Kalinina EV, Chernov NN & & Saprin AN 2008 Involvement of thio-, peroxi-, and glutaredoxins in cellular redox-dependent processes. Biochemistry. Biokhimiia 73 1493–1510. (https://doi.org/10.1134/S0006297908130099)
Li H, Xu C, Li Q, Gao X, Sugano E, Tomita H, Yang L & & Shi S 2017a Thioredoxin 2 offers protection against mitochondrial oxidative stress in H9c2 cells and against myocardial hypertrophy induced by hyperglycemia. International Journal of Molecular Sciences 18 1958. (https://doi.org/10.3390/ijms18091958)
Li Y, Xiang Y, Zhang S, Wang Y, Yang J, Liu W & & Xue F 2017b Intramyocardial injection of thioredoxin 2-expressing lentivirus alleviates myocardial ischemia-reperfusion injury in rats. American Journal of Translational Research 9 4428–4439.
Li YY, Xiang Y, Zhang S, Wang Y, Yang J, Liu W & & Xue FT 2017c Thioredoxin-2 protects against oxygen-glucose deprivation/reperfusion injury by inhibiting autophagy and apoptosis in H9c2 cardiomyocytes. American Journal of Translational Research 9 1471–1482.
Libby P 2002 Inflammation in atherosclerosis. Nature 420 Article 6917. (https://doi.org/10.1038/nature01323)
Lowes DA & & Galley HF 2011 Mitochondrial protection by the thioredoxin-2 and glutathione systems in an in vitro endothelial model of sepsis. Biochemical Journal 436 123–132. (https://doi.org/10.1042/BJ20102135)
Lu J & & Holmgren A 2014 The thioredoxin antioxidant system. Free Radical Biology and Medicine 66 75–87. (https://doi.org/10.1016/j.freeradbiomed.2013.07.036)
Madamanchi NR, Vendrov A & & Runge MS 2005 Oxidative stress and vascular disease. Arteriosclerosis, Thrombosis, and Vascular Biology 25 29–38. (https://doi.org/10.1161/01.ATV.0000150649.39934.13)
Medali T, Couchie D, Mougenot N, Mihoc M, Bergmann O, Derks W, Szweda LI, Yacoub M, Soliman S, Aguib Y, et al.2024 Thioredoxin-1 and its mimetic peptide improve systolic cardiac function and remodeling after myocardial infarction. FASEB Journal 38 e23291. (https://doi.org/10.1096/fj.202300792RR)
Menasché P, Alfieri O, Janssens S, McKenna W, Reichenspurner H, Trinquart L, Vilquin JT, Marolleau JP, Seymour B, Larghero J, et al.2008 The myoblast autologous grafting in ischemic cardiomyopathy (MAGIC) trial: first randomized placebo-controlled study of myoblast transplantation. Circulation 117 1189–1200. (https://doi.org/10.1161/CIRCULATIONAHA.107.734103)
Murry CE, Soonpaa MH, Reinecke H, Nakajima H, Nakajima HO, Rubart M, Pasumarthi KBS, Ismail Virag JI, Bartelmez SH, Poppa V, et al.2004 Haematopoietic stem cells do not transdifferentiate into cardiac myocytes in myocardial infarcts. Nature 428 Article 6983. (https://doi.org/10.1038/nature02446)
Nakada Y, Canseco DC, Thet S, Abdisalaam S, Asaithamby A, Santos CX, Shah AM, Zhang H, Faber JE, Kinter MT, et al.2017 Hypoxia induces heart regeneration in adult mice. Nature 541 222–227. (https://doi.org/10.1038/nature20173)
Nonn L, Williams RR, Erickson RP & & Powis G 2003 The absence of mitochondrial thioredoxin 2 causes massive apoptosis, exencephaly, and early embryonic lethality in homozygous mice. Molecular and Cellular Biology 23 916–922. (https://doi.org/10.1128/MCB.23.3.916-922.2003)
Orlic D, Kajstura J, Chimenti S, Bodine DM, Leri A & & Anversa P 2001 Transplanted adult bone marrow cells repair myocardial infarcts in mice. Annals of the New York Academy of Sciences 938 221–229. (https://doi.org/10.1111/j.1749-6632.2001.tb03592.x)
Paradis AN, Gay MS & & Zhang L 2014 Binucleation of cardiomyocytes: the transition from a proliferative to a terminally differentiated state. Drug Discovery Today 19 602–609. (https://doi.org/10.1016/j.drudis.2013.10.019)
Polizzotti BD, Ganapathy B, Walsh S, Choudhury S, Ammanamanchi N, Bennett DG, dos Remedios CG, Haubner BJ, Penninger JM & & Kuhn B 2015 Stimulation of cardiomyocyte regeneration in neonatal mice and in human myocardium with neuregulin reveals a therapeutic window. Science Translational Medicine 7 281ra45. (https://doi.org/10.1126/scitranslmed.aaa5171)
Porrello ER, Mahmoud AI, Simpson E, Hill JA, Richardson JA, Olson EN & & Sadek HA 2011 Transient regenerative potential of the neonatal mouse heart. Science 331 1078–1080. (https://doi.org/10.1126/science.1200708)
Porrello ER, Mahmoud AI, Simpson E, Johnson BA, Grinsfelder D, Canseco D, Mammen PP, Rothermel BA, Olson EN & & Sadek HA 2013 Regulation of neonatal and adult mammalian heart regeneration by the miR-15 family. PNAS 110 187–192. (https://doi.org/10.1073/pnas.1208863110)
Puente BN, Kimura W, Muralidhar SA, Moon J, Amatruda JF, Phelps KL, Grinsfelder D, Rothermel BA, Chen R, Garcia JA, et al.2014 The oxygen-rich postnatal environment induces cardiomyocyte cell-cycle arrest through DNA damage response. Cell 157 565–579. (https://doi.org/10.1016/j.cell.2014.03.032)
Rybnikova E, Damdimopoulos AE, Gustafsson JA, Spyrou G & & Pelto-Huikko M 2000 Expression of novel antioxidant thioredoxin‐2 in the rat brain. European Journal of Neuroscience 12 1669–1678. (https://doi.org/10.1046/j.1460-9568.2000.00059.x)
Saleh M & & Ambrose JA 2018 Understanding myocardial infarction. F1000Research 7 F1000 Faculty Rev-1378. (https://doi.org/10.12688/f1000research.15096.1)
Spyrou G, Enmark E, Miranda-Vizuete A & & Gustafsson J-Å 1997 Cloning and expression of a novel mammalian thioredoxin. Journal of Biological Chemistry 272 2936–2941. (https://doi.org/10.1074/jbc.272.5.2936)
Zhang R, Al-Lamki R, Bai L, Streb JW, Miano JM, Bradley J & & Min W 2004 Thioredoxin-2 inhibits mitochondria-located ASK1-mediated apoptosis in a JNK-independent manner. Circulation Research 94 1483–1491. (https://doi.org/10.1161/01.RES.0000130525.37646.a7)
Zhang H, Luo Y, Zhang W, He Y, Dai S, Zhang R, Huang Y, Bernatchez P, Giordano FJ, Shadel G, et al.2007 Endothelial-specific expression of mitochondrial thioredoxin improves endothelial cell function and reduces atherosclerotic lesions. American Journal of Pathology 170 1108–1120. (https://doi.org/10.2353/ajpath.2007.060960)
