Venoarterial extracorporeal membrane oxygenation (VA-ECMO) provides hemodynamic rescue for patients encountering right or left ventricular (RV or LV) decompensation, particularly after surgery for congenital heart defects. ECMO, supported metabolically by parenteral nutrition, provides reductions in myocardial work and energy demand and, therefore, enhances functional recovery. The RV must often assume systemic ventricular pressures and function on weaning from VA-ECMO. However the substrate utilization responses of the RV to VA-ECMO or stimulation are unknown. We determined RV and LV substrate utilization response to VA-ECMO in immature swine heart. Mixed-breed male Yorkshire pigs (33-49 days old) underwent normal pressure volume loading (control, = 5) or were unloaded by VA-ECMO (ECMO, = 10) for 8 h. Five pigs with ECMO received intravenous thyroid hormone [triiodothyronine (T)] to alter substrate utilization. Carbon 13 (C)-labeled substrates (lactate and medium-chain and long-chain fatty acids) were systemically infused as metabolic tracers. Analyses by nuclear magnetic resonance showed that both ventricles have similar trends of fractional C-labeled substrate contributions to the citric acid cycle under control conditions. VA-ECMO produced higher long-chain fatty acids and lower lactate contribution to the citric acid cycle via inhibition of pyruvate dehydrogenase, whereas T promoted lactate metabolism in both ventricles. However, these metabolic shifts were smaller in RV, and RV fatty acid contributions showed minimal response to perturbations. Furthermore, VA-ECMO and T also achieved high [phosphocreatine]/[ATP] and low [NADH]/[NAD] in LV but not in RV. These data suggest that the RV shows decreased ability to modify substrate utilization and achieve improvements in energy supply/demand during VA-ECMO. We showed that the right ventricle unloaded by venoarterial extracorporeal membrane oxygenation (VA-ECMO) has diminished capacity to alter substrate utilization compared with the left ventricle. This decrease in metabolic flexibility contributes to the inability to increase high-energy phosphate reserves during myocardial rest by VA-ECMO.
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http://dx.doi.org/10.1152/ajpheart.00835.2016 | DOI Listing |
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State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China.
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State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China. Electronic address:
Background: The industrial production of L-threonine faces challenges because of high production costs, especially those of substrates, meaning new production methods are needed.
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School of Science, Xihua University, Chengdu 610039 PR China. Electronic address:
Beta - stimulant, that is, β - adrenergic stimulant, also known as β - agonists, is bioactive catecholamine compounds naturally produced in animals' adrenal medulla glands that induce relaxation in asthmatic airway smooth muscles upon inhalation while also temporarily boosting athletic alertness and alleviating fatigue. However, their potential for dependency poses health risks including unnoticed exacerbation leading to severe illness or fatality prompting their inclusion on WADA's prohibited substances list. Surface - enhanced Raman spectroscopy (SERS) offers a rapid, sensitive, and label - free means for identifying characteristic peaks associated with β - agonist compounds.
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Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province, School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004, PR China. Electronic address:
Org Lett
January 2025
Key Laboratory of Material Chemistry for Energy Conversion and Storage, Ministry of Education, Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medica, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, China.
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