Maple syrup urine disease (MSUD) is a metabolic disorder biochemically characterized by the accumulation of branched-chain alpha-amino acids (BCAA) and their branched-chain alpha-keto acids (BCKA) in blood and tissues. Neurological dysfunction is usually present in the patients, but the mechanisms of brain damage in this disease are far from be understood. The main objective of this study was to investigate the mechanisms by which BCAA inhibit creatine kinase activity, a key enzyme of energy homeostasis, in the brain cortex of 21-day-old Wistar rats. For the kinetic studies, Lineweaver-Burk and a modification of the Chevillard et al. plots were used to characterize the mechanisms of enzyme inhibition. The results indicated that BCAA inhibit creatine kinase by competition with the substrates phosphocreatine and ADP at the active site. Considering the crucial role creatine kinase plays in energy homeostasis in brain, if these effects also occur in the brain of MSUD patients, it is possible that inhibition of this enzyme activity may contribute to the brain damage found in this disease. In this case, it is possible that creatine supplementation to the diet might benefit MSUD patients.
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http://dx.doi.org/10.1016/s0736-5748(03)00028-5 | DOI Listing |
ACS Synth Biol
January 2025
Centre for Engineering Biology, Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, U.K.
The "Protein synthesis Using Recombinant Elements" ("PURE") system is a minimal biochemical system capable of carrying out cell-free protein synthesis using defined enzymatic components. This study extends PURE by integrating an ATP regeneration system based on pyruvate oxidase, acetate kinase, and catalase. The new pathway generates acetyl phosphate from pyruvate, phosphate, and oxygen, which is used to rephosphorylate ATP .
View Article and Find Full Text PDFEur J Med Res
January 2025
Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China.
Background: Astragalus injection has been utilized in traditional Chinese medicine to treat a variety of diseases. The purpose of this systematic review was to evaluate the effectiveness of Astragalus injection in the treatment of viral myocarditis.
Methods: English databases such as PubMed, Cochrane Library, and EMBASE, and Chinese databases of Sino Med, China National Knowledge Infrastructure (CNKI), the VIP Information Resource Integration Service Platform, and Wanfang Data Information Site, were searched from their inception until May 1, 2024.
Heart Lung
January 2025
University of Foggia, Department of Medical and Surgical Sciences, Foggia, Italy. Electronic address:
Background: It is crucial to distinguish type-1 myocardial infarction (T1MI) from type-2 myocardial infarction (T2MI) at admission and during hospitalization to avoid unnecessary invasive exams and inappropriate admissions to the acute cardiac care unit.
Objectives: The purpose of the study was to define a simple profile derived from commonly used biomarkers to differentiate T1MI from T2MI.
Methods: We prospectively enrolled in an observational study 213 iconsecutive patients with a provisional diagnosis of non-ST-elevation acute myocardial infarction (NSTEMI) admitted to the Cardiology Department.
Nanoscale
January 2025
Department of Chemistry, Federal University of São Paulo (UNIFESP), Diadema, SP, Brazil.
This study aims to use superparamagnetic iron oxide nanoparticles (SPIONs), specifically magnetite (FeO), to deliver deflazacort (DFZ) and ibuprofen (IBU) to Duchenne muscular dystrophy-affected (DMD) mouse muscles using an external magnetic field. The SPIONs are synthesized by the co-precipitation method, and their surfaces are functionalized with L-cysteine to anchor the drugs, considering that the cysteine on the surface of the SPIONs in the solid state dimerizes to form the cystine molecule, creating the FeO-(Cys)-DFZ and FeO-(Cys)-IBU systems for tests. The FeO nanoparticles (NPs) were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), and magnetic measurements.
View Article and Find Full Text PDFShock
December 2024
Department of Emergency Medicine, Ningbo Medical Center Lihuili Hospital, The Affiliated Lihuili Hospital of Ningbo University, Ningbo, China.
Introduction: Dl-3-n-butylphthalide (NBP), a small molecular compound extracted from celery seeds, has been shown to exhibit diverse pharmacological activities, including anti-inflammatory, antioxidative, and anti-apoptotic effects. Recent studies have highlighted its efficacy in treating various cardiovascular conditions, such as myocardial infarction, hypertrophy, heart failure, and cardiotoxicity. This study aimed to investigate whether NBP could alleviate cardiac dysfunction and injury following hemorrhage-induced cardiac arrest (HCA) in a porcine model and elucidate its potential mechanisms.
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