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Doul J, Minaříková M, Charvátová Z, Maxová H. Nitric oxide is involved in the cardioprotection of neonatal rat hearts, but not in neonatal ischemic postconditioning. Physiol Rep 2024; 12:e16147. [PMID: 39097984 PMCID: PMC11298247 DOI: 10.14814/phy2.16147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Revised: 06/29/2024] [Accepted: 07/04/2024] [Indexed: 08/06/2024] Open
Abstract
The cardioprotective effect of ischemic preconditioning (IPC) and ischemic postconditioning (IPoC) in adult hearts is mediated by nitric oxide (NO). During the early developmental period, rat hearts exhibit higher resistance to ischemia-reperfusion (I/R) injury, contain higher levels of serum nitrates, and their resistance cannot be further increased by IPC or IPoC. NOS blocker (L-NAME) lowers their high resistance. Wistar rat hearts (postnatal Days 1 and 10) were perfused according to Langendorff and exposed to 40 min of global ischemia followed by reperfusion with or without IPoC. NO and reactive oxygen species donors (DEA-NONO, SIN-1) and L-NAME were administered. Tolerance to ischemia decreased between Days 1 and 10. DEA-NONO (low concentrations) significantly increased tolerance to I/R injury on both Days 1 and 10. SIN-1 increased tolerance to I/R injury on Day 10, but not on Day 1. L-NAME significantly reduced resistance to I/R injury on Day 1, but actually increased resistance to I/R injury on Day 10. Cardioprotection by IPoC on Day 10 was not affected by either NO donors or L-NAME. It can be concluded that resistance of the neonatal heart to I/R injury is NO dependent, but unlike in adult hearts, cardioprotective interventions, such as IPoC, are most likely NO independent.
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Affiliation(s)
- Jan Doul
- Department of Pathophysiology, Second Faculty of MedicineCharles UniversityPragueCzech Republic
| | - Marcela Minaříková
- Department of Physiology, Second Faculty of MedicineCharles UniversityPragueCzech Republic
| | - Zuzana Charvátová
- Department of Pathophysiology, Second Faculty of MedicineCharles UniversityPragueCzech Republic
| | - Hana Maxová
- Department of Pathophysiology, Second Faculty of MedicineCharles UniversityPragueCzech Republic
- Center for Experimental MedicineInstitute for Clinical and Experimental MedicinePragueCzech Republic
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An isolated retrograde-perfused newborn mouse heart preparation. MethodsX 2020; 7:101058. [PMID: 32983923 PMCID: PMC7492986 DOI: 10.1016/j.mex.2020.101058] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/02/2020] [Indexed: 11/24/2022] Open
Abstract
The Langendorff-perfused model is a powerful tool to study biological responses in the isolated heart in the absence of confounders. The model has been adapted recently to enable study of the isolated mouse heart and the effects of genetic manipulation. Unfortunately, the small size and fragility of the mouse heart pose significant challenges, limiting application of the Langendorff model to the study of adult mice. Cardiac development is a complex and dynamic process that is incompletely understood. Thus, establishing an isolated-perfused heart model in the newborn mouse would be an important and necessary advance. Here we present a method to successfully cannulate and perfuse the isolated newborn murine heart. We describe the basic and fundamental physiological characteristics of the ex-vivo retrograde-perfused beating neonatal heart in wild-type C57Bl/6 male mice. Our approach will enable future study of the physiological and pharmacological responses of the isolated immature murine heart to enhance knowledge of how developmental cardiac biology impacts health and disease.The Langendorff model is a powerful tool to study the heart without confounders. An isolated-perfused newborn murine heart model has yet to be established. We demonstrate the first successful isolated neonatal murine heart preparation.
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Ostadal B, Drahota Z, Houstek J, Milerova M, Ostadalova I, Hlavackova M, Kolar F. Developmental and sex differences in cardiac tolerance to ischemia-reperfusion injury: the role of mitochondria 1. Can J Physiol Pharmacol 2019; 97:808-814. [PMID: 30893574 DOI: 10.1139/cjpp-2019-0060] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Age and sex play an essential role in the cardiac tolerance to ischemia-reperfusion injury: cardiac resistance significantly decreases during postnatal maturation and the female heart is more tolerant than the male myocardium. It is widely accepted that mitochondrial dysfunction, and particularly mitochondrial permeability transition pore (MPTP) opening, plays a major role in determining the extent of cardiac ischemia-reperfusion injury. We have observed that the MPTP sensitivity to the calcium load differs in mitochondria isolated from neonatal and adult myocardium, as well as from adult male and female hearts. Neonatal and female mitochondria are more resistant both in the extent and in the rate of mitochondrial swelling induced by high calcium concentration. Our data further suggest that age- and sex-dependent specificity of the MPTP is not the result of different amounts of ATP synthase and cyclophilin D: neonatal and adult hearts, similarly as the male and female hearts, contain comparable amounts of MPTP and its regulatory protein cyclophilin D. We can speculate that the lower sensitivity of MPTP to the calcium-induced swelling may be related to the higher ischemic tolerance of both neonatal and female myocardium.
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Affiliation(s)
- B Ostadal
- Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic.,Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic
| | - Z Drahota
- Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic.,Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic
| | - J Houstek
- Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic.,Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic
| | - M Milerova
- Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic.,Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic
| | - I Ostadalova
- Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic.,Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic
| | - M Hlavackova
- Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic.,Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic
| | - F Kolar
- Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic.,Institute of Physiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague 4 Czech Republic
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4
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Possible role of mitochondrial K-ATP channel and nitric oxide in protection of the neonatal rat heart. Mol Cell Biochem 2018; 450:35-42. [PMID: 29802596 PMCID: PMC6328520 DOI: 10.1007/s11010-018-3370-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 05/17/2018] [Indexed: 12/20/2022]
Abstract
Cardioprotective effect of ischemic preconditioning (IPC) and ischemic postconditioning (IPoC) in adult hearts is mediated by mitochondrial-K-ATP channels and nitric oxide (NO). During early developmental period, rat hearts exhibit higher resistance to ischemia–reperfusion (I/R) injury and their resistance cannot be further increased by IPC or IPoC. Therefore, we have speculated, whether mechanisms responsible for high resistance of neonatal heart may be similar to those of IPC and IPoC. To test this hypothesis, rat hearts isolated on days 1, 4, 7, and 10 of postnatal life were perfused according to Langendorff. Developed force (DF) of contraction was measured. Hearts were exposed to 40 min of global ischemia followed by reperfusion up to the maximum recovery of DF. IPoC was induced by 5 cycles of 10-s ischemia. Mito-K-ATP blocker (5-HD) was administered 5 min before ischemia and during first 20 min of reperfusion. Another group of hearts was isolated for biochemical analysis of 3-nitrotyrosine, and serum samples were taken to measure nitrate levels. Tolerance to ischemia did not change from day 1 to day 4 but decreased on days 7 and 10. 5-HD had no effect either on neonatal resistance to I/R injury or on cardioprotective effect of IPoC on day 10. Significant difference was found in serum nitrate levels between days 1 and 10 but not in tissue 3-nitrotyrosine content. It can be concluded that while there appears to be significant difference of NO production, mito-K-ATP and ROS probably do not play role in the high neonatal resistance to I/R injury.
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Mitsuhashi T, Uemoto R, Ishikawa K, Yoshida S, Ikeda Y, Yagi S, Matsumoto T, Akaike M, Aihara KI. Endothelial Nitric Oxide Synthase-Independent Pleiotropic Effects of Pitavastatin Against Atherogenesis and Limb Ischemia in Mice. J Atheroscler Thromb 2017; 25:65-80. [PMID: 28592707 PMCID: PMC5770225 DOI: 10.5551/jat.37747] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Aim: Statins have a protective impact against cardiovascular diseases through not only lipid-lowering effects but also pleiotropic effects, including activation of the endothelial nitric oxide synthase (eNOS) system. We aimed to clarify the protective effects of a statin against atherogenesis and ischemia in eNOS−/− mice. Methods: Study 1. eNOS−/−Apolipoprotein E (ApoE)−/− mice were treated with a vehicle or pitavastatin (0.3 mg/kg/day) for 4 weeks. Study 2. eNOS−/− mice were also treated with a vehicle or the same dose of pitavastatin for 2 weeks prior to hind-limb ischemia. Results: In Study 1, pitavastatin attenuated plaque formation and medial fibrosis of the aortic root with decreased macrophage infiltration in eNOS−/−ApoE−/− mice. PCR array analysis showed reductions in aortic gene expression of proatherogenic factors, including Ccl2 and Ccr2 in pitavastatin-treated double mutant mice. In addition, pitavastatin activated not only atherogenic p38MAPK and JNK but also anti-atherogenic ERK1/2 and ERK5 in the aorta of the double mutant mice. In Study 2, pitavastatin prolonged hind-limb survival after the surgery with increased BCL2-to-BAX protein ratio and inactivated JNK. Enhanced expression of anti-apoptotic genes, including Vegf, Api5, Atf5, Prdx2, and Dad1, was observed in the ischemic limb of pitavastatin-treated eNOS−/− mice. Furthermore, pitavastatin activated both aortic and skeletal muscle AMPK in the eNOS-deficient vascular injury models. Conclusion: Pitavastatin exerts eNOS-independent protective effects against atherogenesis and hindlimb ischemia in mice, which may occur via modifications on key molecules such as AMPK and diverse molecules.
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Affiliation(s)
| | - Ryoko Uemoto
- Department of Community Medicine for Diabetes and Metabolic Disorders, Tokushima University
| | | | - Sumiko Yoshida
- Department of Hematology, Endocrinology & Metabolism, Tokushima University
| | | | - Shusuke Yagi
- Department of Cardiovascular Medicine, Tokushima University Graduate School of Biomedical Sciences
| | - Toshio Matsumoto
- Fujii Memorial Institute of Medical Sciences, Tokushima University
| | | | - Ken-Ichi Aihara
- Department of Community Medicine for Diabetes and Metabolic Disorders, Tokushima University
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Exenatide Regulates Substrate Preferences Through the p38γ MAPK Pathway After Ischaemia/Reperfusion Injury in a Rat Heart. Heart Lung Circ 2017; 26:404-412. [DOI: 10.1016/j.hlc.2016.07.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 07/08/2016] [Accepted: 07/15/2016] [Indexed: 11/20/2022]
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7
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Chen H, Liu S, Liu X, Yang J, Wang F, Cong X, Chen X. Lysophosphatidic Acid Pretreatment Attenuates Myocardial Ischemia/Reperfusion Injury in the Immature Hearts of Rats. Front Physiol 2017; 8:153. [PMID: 28377726 PMCID: PMC5359218 DOI: 10.3389/fphys.2017.00153] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 02/27/2017] [Indexed: 02/01/2023] Open
Abstract
The cardioprotection of the immature heart during cardiac surgery remains controversial due to the differences between the adult heart and the newborn heart. Lysophosphatidic acid (LPA) is a small bioactive molecule with diverse functions including cell proliferation and survival via its receptor: LPA1–LPA6. We previously reported that the expressions of LPA1 and LPA3 in rat hearts were much higher in immature hearts and then declined rapidly with age. In this study, we aimed to investigate whether LPA signaling plays a potential protective role in immature hearts which had experienced ischemia/reperfusion (I/R) injury. The results showed that in Langendorff-perfused immature rat hearts (2 weeks), compared to I/R group, LPA pretreatment significantly enhanced the cardiac function, attenuated myocardial infarct size and CK-MB release, decreased myocardial apoptosis and increased the expression of pro-survival signaling molecules. All these effects could be abolished by Ki16425, an antagonist to LPA1 and LPA3. Similarly, LPA pretreatment protected H9C2 from hypoxia-reoxygenation (H/R) induced apoptosis and necrosis in vitro. The mechanisms underlying the anti-apoptosis effects were related to activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinas B (AKT) signaling pathways as well as phosphorylation of the downstream effector of AKT, glycogen synthase kinase 3 beta (GSK3β), through LPA1 and/or LPA3. What's more, we found that LPA preconditioning increased glucose uptake of H9C2 subjected to H/R by the activation of AMP-Activated Protein Kinase (AMPK) but not the translocation of GLUT4. In conclusion, our study indicates that LPA is a potent survival factor for immature hearts against I/R injuries and has the potential therapeutic function as a cardioplegia additive for infantile cardiac surgery.
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Affiliation(s)
- Haibo Chen
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences - Peking Union Medical College Beijing, China
| | - Si Liu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences - Peking Union Medical College Beijing, China
| | - Xuewen Liu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences - Peking Union Medical College Beijing, China
| | - Jinjing Yang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences - Peking Union Medical College Beijing, China
| | - Fang Wang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences - Peking Union Medical College Beijing, China
| | - Xiangfeng Cong
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences - Peking Union Medical College Beijing, China
| | - Xi Chen
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences - Peking Union Medical College Beijing, China
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8
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Shimada S, Del Nido PJ, Friehs I. Development of a Vascularized Heterotopic Neonatal Rat Heart Transplantation Model. Eur Surg Res 2016; 57:240-251. [PMID: 27544776 DOI: 10.1159/000447691] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Accepted: 06/17/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND/PURPOSE Rodent adult-to-adult heterotopic heart transplantation is a well-established animal model, and the detailed surgical technique with several modifications has been previously described. In immature donor organ transplantation, however, the surgical technique needs to be revised given the smaller size and fragility of the donor graft. Here, we report our surgical technique for heterotopic abdominal (AHTx) and femoral (FHTx) neonatal rat heart transplantation based on an experience of over 300 cases. METHODS Heterotopic heart transplantation was conducted in syngeneic Lewis rats. Neonatal rats (postnatal day 2-4) served as donors. AHTx was performed by utilizing the conventional adult-to-adult transplant method with specific modifications for optimal aortotomy and venous anastomosis. In the FHTx, the donor heart was vascularized by connecting the donor's aorta and pulmonary artery to the recipient's right femoral artery and vein, respectively, in an end-to-end manner. A specifically fashioned butterfly-shaped rubber sheet was used to align the target vessels properly. The transplanted graft was visually assessed for its viability and was accepted as a technical success when the viability met specific criteria. Successfully transplanted grafts were subject to further postoperative evaluation. Forty cases (AHTx and FHTx; n = 20 each) were compared regarding perioperative parameters and outcomes. RESULTS Both models were technically feasible (success rate: AHTx 75% vs. FHTx 70%) by refining the conventional heterotopic transplant technique. Injury to the fragile donor aorta and congestion of the graft due to suboptimal venous connection were predominant causes of failure, leading to refractory bleeding and poor graft viability. Although the FHTx required significantly longer operation time and graft ischemic time, the in situ graft viabilities were comparable. The FHTx provided better postoperative monitoring as it enabled daily graft palpation and better echocardiographic visualization. CONCLUSIONS We describe detailed surgical techniques for AHTx and FHTx while addressing neonatal donor-specific issues. Following our recommendations potentially reduces the learning curve to achieve reliable and reproducible results with these challenging animal models.
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Affiliation(s)
- Shogo Shimada
- Department of Cardiac Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Mass., USA
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9
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Kassan A, Pham U, Nguyen Q, Reichelt ME, Cho E, Patel PM, Roth DM, Head BP, Patel HH. Caveolin-3 plays a critical role in autophagy after ischemia-reperfusion. Am J Physiol Cell Physiol 2016; 311:C854-C865. [PMID: 27707689 PMCID: PMC5206298 DOI: 10.1152/ajpcell.00147.2016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 10/03/2016] [Indexed: 12/21/2022]
Abstract
Autophagy is a dynamic recycling process responsible for the breakdown of misfolded proteins and damaged organelles, providing nutrients and energy for cellular renovation and homeostasis. Loss of autophagy is associated with cardiovascular diseases. Caveolin-3 (Cav-3), a muscle-specific isoform, is a structural protein within caveolae and is critical to stress adaptation in the heart. Whether Cav-3 plays a role in regulating autophagy to modulate cardiac stress responses remains unknown. In the present study, we used HL-1 cells, a cardiac muscle cell line, with stable Cav-3 knockdown (Cav-3 KD) and Cav-3 overexpression (Cav-3 OE) to study the impact of Cav-3 in regulation of autophagy. We show that traditional stimulators of autophagy (i.e., rapamycin and starvation) result in upregulation of the process in Cav-3 OE cells while Cav-3 KD cells have a blunted response. Cav-3 coimmunoprecipitated with beclin-1 and Atg12, showing an interaction of caveolin with autophagy-related proteins. In the heart, autophagy may be a major regulator of protection from ischemic stress. We found that Cav-3 KD cells have a decreased expression of autophagy markers [beclin-1, light chain (LC3-II)] after simulated ischemia and ischemia-reperfusion (I/R) compared with WT, whereas OE cells showed increased expression. Moreover, Cav-3 KD cells showed increased cell death and higher level of apoptotic proteins (cleaved caspase-3 and cytochrome c) with suppressed mitochondrial function in response to simulated ischemia and I/R, whereas Cav-3 OE cells were protected and had preserved mitochondrial function. Taken together, these results indicate that autophagy regulates adaptation to cardiac stress in a Cav-3-dependent manner.
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Affiliation(s)
- Adam Kassan
- Department of Anesthesiology, University of California, San Diego, La Jolla, California.,Sam and Rose Stein Institute for Research on Aging, Department of Psychiatry, School of Medicine, University of California, San Diego, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Uyen Pham
- Department of Anesthesiology, University of California, San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Quynhmy Nguyen
- Department of Anesthesiology, University of California, San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Melissa E Reichelt
- School of Biomedical Sciences, University of Queensland, St. Lucia, Queensland, Australia
| | - Eunbyul Cho
- Department of Anesthesiology, University of California, San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Piyush M Patel
- Department of Anesthesiology, University of California, San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - David M Roth
- Department of Anesthesiology, University of California, San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Brian P Head
- Department of Anesthesiology, University of California, San Diego, La Jolla, California.,Veterans Affairs San Diego Healthcare System, San Diego, California; and
| | - Hemal H Patel
- Department of Anesthesiology, University of California, San Diego, La Jolla, California; .,Veterans Affairs San Diego Healthcare System, San Diego, California; and
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Iyyathurai J, Decuypere JP, Leybaert L, D'hondt C, Bultynck G. Connexins: substrates and regulators of autophagy. BMC Cell Biol 2016; 17 Suppl 1:20. [PMID: 27229147 PMCID: PMC4896244 DOI: 10.1186/s12860-016-0093-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Connexins mediate intercellular communication by assembling into hexameric channel complexes that act as hemichannels and gap junction channels. Most connexins are characterized by a very rapid turn-over in a variety of cell systems. The regulation of connexin turn-over by phosphorylation and ubiquitination events has been well documented. Moreover, different pathways have been implicated in connexin degradation, including proteasomal and lysosomal-based pathways. Only recently, autophagy emerged as an important connexin-degradation pathway for different connexin isoforms. As such, conditions well known to induce autophagy have an immediate impact on the connexin-expression levels. This is not only limited to experimental conditions but also several pathophysiological conditions associated with autophagy (dys)function affect connexin levels and their presence at the cell surface as gap junctions. Finally, connexins are not only substrates of autophagy but also emerge as regulators of the autophagy process. In particular, several connexin isoforms appear to recruit pre-autophagosomal autophagy-related proteins, including Atg16 and PI3K-complex components, to the plasma membrane, thereby limiting their availability and capacity for regulating autophagy.
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Affiliation(s)
- Jegan Iyyathurai
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department Cellular and Molecular Medicine, Campus Gasthuisberg O/N-I bus 802, Herestraat 49, B-3000, Leuven, Belgium
| | - Jean-Paul Decuypere
- KU Leuven, Laboratory for Membrane Trafficking, Department of Human Genetics, and VIB-Center for the Biology of Disease, Campus Gasthuisberg, O/N-IV, 7.159, Herestraat 49, 3000, Leuven, Belgium
| | - Luc Leybaert
- Ghent University, Physiology Group, Department of Basic Medical Sciences, 9000, Ghent, Belgium
| | - Catheleyne D'hondt
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department Cellular and Molecular Medicine, Campus Gasthuisberg O/N-I bus 802, Herestraat 49, B-3000, Leuven, Belgium
| | - Geert Bultynck
- KU Leuven, Laboratory of Molecular and Cellular Signaling, Department Cellular and Molecular Medicine, Campus Gasthuisberg O/N-I bus 802, Herestraat 49, B-3000, Leuven, Belgium.
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Doul J, Charvátová Z, Ošťádalová I, Kohutiar M, Maxová H, Ošťádal B. Neonatal rat hearts cannot be protected by ischemic postconditioning. Physiol Res 2015; 64:789-94. [PMID: 26047384 DOI: 10.33549/physiolres.932981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Although there are abundant data on ischemic postconditioning (IPoC) in the adult myocardium, this phenomenon has not yet been investigated in neonatal hearts. To examine possible protective effects of IPoC, rat hearts isolated on days 1, 4, 7 and 10 of postnatal life were perfused according to Langendorff. Developed force (DF) of contraction was measured by an isometric force transducer. Hearts were exposed to 40 or 60 min of global ischemia followed by reperfusion up to the maximum recovery of DF. IPoC was induced by three cycles of 10, 30 or 60 s periods of global ischemia/reperfusion. To further determine the extent of ischemic injury, lactate dehydrogenase (LDH) release was measured in the coronary effluent. Tolerance to ischemia did not change from day 1 to day 4 but decreased to days 7 and 10. None of the postconditioning protocols tested led to significant protection on the day 10. Prolonging the period of sustained ischemia to 60 min on day 10 did not lead to better protection. The 3x30 s protocol was then evaluated on days 1, 4 and 7 without any significant effects. There were no significant differences in LDH release between postconditioned and control groups. It can be concluded that neonatal hearts cannot be protected by ischemic postconditioning during first 10 days of postnatal life.
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Affiliation(s)
- J Doul
- Department of Pathophysiology, Second Faculty of Medicine, Charles University in Prague, Prague, Czech Republic.
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12
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Chen F, Sun ZW, Ye LF, Fu GS, Mou Y, Hu SJ. Lycopene protects against apoptosis in hypoxia/reoxygenation‑induced H9C2 myocardioblast cells through increased autophagy. Mol Med Rep 2014; 11:1358-65. [PMID: 25351505 DOI: 10.3892/mmr.2014.2771] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 09/24/2014] [Indexed: 11/06/2022] Open
Abstract
Lycopene (Ly), the most common type of antioxidant in the majority of diet types, provides tolerance to ischemia/reperfusion injury. However, the underlying mechanism of the protective effects observed following Ly administration remains poorly investigated. The aim of the current study was to investigate whether Ly prevents damage to hypoxia/reoxygenation (HR)‑induced H9C2 myocardioblasts in an autophagy‑dependent manner. The levels of autophagic markers were detected using western blotting, the level of apoptosis was detected using western blotting and flow cytometry. The activation of autophagy was impaired via knockdown of the expression of 'microtubule‑associated protein 1‑light chain 3β (MAP1LC3B)' and 'Beclin 1'. After 16 h hypoxia, followed by 2 h reoxygenation, the expression levels of the microtubule‑associated protein 1A/1B‑light chain 3 (LC3) and Βeclin 1 autophagic biomarkers, and cell viability were reduced, whereas the percentage of apoptotic cells, and the expression levels of the Bax/B‑cell lymphoma 2 (Bcl‑2) and active caspase‑3 apoptotic biomarkers were increased. Pre‑incubation of the cells with different Ly concentrations reversed the HR‑induced inhibition of autophagy and cell viability, and the HR‑induced elevation in apoptotic levels. The induction of autophagy was accompanied by reduced apoptosis, and decreased expression levels of Bax/Bcl‑2 and active caspase‑3. In addition, the impairment of autophagy by silencing the expression of MAP1LC3B and Beclin 1 accelerated HR‑induced H9C2 cell apoptosis and the Ly‑mediated protective effects disappeared. Furthermore, Bax/Bcl‑2 and active caspase‑3 expression levels were increased. Moreover, Ly‑induced autophagy was associated with increased adenosine monophosphate kinase (AMPK) phosphorylation. Suppressed AMPK phosphorylation using compound C terminates Ly‑mediated cytoprotective effects. Ly treatment improves cell viability and reduces apoptosis as a result of the activation of the adaptive autophagic response on HR‑induced H9C2 myocardioblasts. AMPK phosphorylation may be involved in the progression.
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Affiliation(s)
- Fei Chen
- Institution of Cardiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
| | - Ze-Wei Sun
- Institution of Cardiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
| | - Li-Fang Ye
- Institution of Cardiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
| | - Guo-Sheng Fu
- Department of Cardiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310012, P.R. China
| | - Yun Mou
- Department of Ultrasound, The Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
| | - Shen-Jiang Hu
- Institution of Cardiology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, P.R. China
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Ostadal B, Ostadalova I, Kolar F, Sedmera D. Developmental determinants of cardiac sensitivity to hypoxia. Can J Physiol Pharmacol 2014; 92:566-74. [DOI: 10.1139/cjpp-2013-0498] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cardiac sensitivity to oxygen deprivation changes significantly during ontogenetic development. However, the mechanisms for the higher tolerance of the immature heart, possibilities of protection, and the potential impact of perinatal hypoxia on cardiac tolerance to oxygen deprivation in adults have not yet been satisfactorily clarified. The hypoxic tolerance of an isolated rat heart showed a triphasic pattern: significant decrease from postnatal day 1 to 7, followed by increase to the weaning period, and final decline to adulthood. We have observed significant ontogenetic changes in mitochondrial oxidative phosphorylation and mitochondrial membrane potential, as well as in the role of the mitochondrial permeability transition pores in myocardial injury. These results support the hypothesis that cardiac mitochondria are deeply involved in the regulation of cardiac tolerance to oxygen deprivation during ontogenetic development. Ischemic preconditioning failed to increase tolerance to oxygen deprivation in the highly tolerant hearts of newborn rats. Chronic hypoxic exposure during early development may cause in-utero or neonatal programming of several genes that can change the susceptibility of the adult heart to ischemia–reperfusion injury; this effect is sex dependent. These results would have important clinical implications, since cardiac sensitivity in adult patients may be significantly affected by perinatal hypoxia in a sex-dependent manner.
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Affiliation(s)
- Bohuslav Ostadal
- Institute of Physiology, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague, Czech Republic
| | - Ivana Ostadalova
- Institute of Physiology, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague, Czech Republic
| | - Frantisek Kolar
- Institute of Physiology, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague, Czech Republic
| | - David Sedmera
- Institute of Physiology, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague, Czech Republic
- Institute of Anatomy, First Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
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