Cardiac energetics alteration in a chronic hypoxia rat model: A non-invasive in vivo 31P magnetic resonance spectroscopy study

2021 ◽  
pp. 1-11
Author(s):  
Xiaohan Yuan ◽  
Xiaomei Zhu ◽  
Yang Chen ◽  
Wangyan Liu ◽  
Wen Qian ◽  
...  

BACKGROUND: Energetics alteration plays a crucial role in the myocardial injury process in chronic hypoxia diseases (CHD). 31P magnetic resonance spectroscopy (MRS) can investigate alterations in cardiac energetics in vivo. OBJECTIVE: To characterize the potential value of 31P MRS in evaluating cardiac energetics alteration of chronic hypoxic rats (CHRs). METHODS: Twenty-four CHRs were induced by SU5416 combined with hypoxia and divided into four groups according to the modeling time of one, two, three and five weeks, respectively. Control group also contains six rats. 31P MRS was performed weekly and the ratio of concentrations of phosphocreatine (PCr) to adenosine triphosphate (ATP) (PCr/ATP) was obtained. In addition, the cardiac structure index and systolic function parameters, including the right ventricular ejection fraction (RVEF), right ventricular end-diastolic volume index (RVEDVi), right ventricular end-systolic volume index (RVESVi), and the left ventricular function parameters, were measured. RESULTS: Decreased resting cardiac PCr/ATP ratio in CHRs was observed at the first week, compared to the control group (2.90±0.35 vs. 3.31±0.45, p = 0.045), while the RVEF, RVEDVi, and RVESVi decreased at the second week (p <  0.05). The PCr/ATP ratio displayed a significant correlation with RVEF (r = 0.605, p = 0.001), RVEDVi, and RVESVi (r = –0.661, r = –0.703; p <  0.001). CONCLUSIONS: 31P MRS can easily detect the cardiac energetics alteration in a CHR model before the onset of ventricular dysfunction. The decreased PCr/ATP ratio likely reveales myocardial injury and cardiac dysfunction.

2021 ◽  
Author(s):  
Xiaohan Yuan ◽  
Xiaomei Zhu ◽  
Yang Chen ◽  
Wangyan Liu ◽  
Wen Qian ◽  
...  

Abstract Background: Energetics alteration plays a key role in the process of myocardial injury in chronic hypoxic diseases (CHD). 31P magnetic resonance spectroscopy (MRS) can investigate alterations in cardiac energetics in vivo. This study was aimed to characterize the potential value of 31P MRS in evaluating cardiac energetics alteration of chronic hypoxia rats (CHR).Methods: Twenty-four CHRs were induced by SU5416 combined with hypoxia, and six rats were raised as control group. 31P MRS was performed weekly and the ratio of concentrations of phosphocreatine (PCr) to adenosine triphosphate (ATP) (PCr/ATP) was obtained. The index of cardiac structure and systolic function parameters, including the right ventricular function (RVEF), right ventricular end-diastolic volume index (RVEDVi), right ventricular end-systolic volume index (RVESVi), the left ventricular function parameters were also measured.Results: The declension of resting cardiac PCr/ATP ratio in CHR was observed at the 1st week, compared to control group (2.90±0.35 vs. 3.31±0.45, p =0.045), while the RVEF,RVEDVi and RVESVi decreased at the 2nd week (p<0.05). The PCr/ATP ratio displayed a significant correlation with RVEF(r = 0.605, p = 0.001),RVEDVi and RVESVi (r = -0.661, r = -0.703; p<0.001).Conclusions: 31P MRS can early detect the cardiac energetics alteration in CHR model before the onset of ventricular dysfunction. The decrease of PCr/ATP ratio likely revealed myocardial injury and cardiac dysfunction.


2019 ◽  
pp. 16-23
Author(s):  
Mírian Celly Medeiros Miranda David ◽  
Letycia dos Santos Neves ◽  
Carlúcia Ithamar Fernandes Franco ◽  
Rhowena Jane Barbosa de Matos

Introduction: Migraine has a neurological origin and is characterized by failure of central modulation leading to neuronal hyperexcitability. Among the factors related to such excitability is the mitochondrial dysfunction that has been considered since the 1980s. Objective: To investigate changes in the cerebral energetic metabolism of individuals with migraine through phosphorus magnetic resonance spectroscopy (31P-MRS). Methods: It was searched articles on Pubmed, Web of Science and Science Direct betweenof June, 2018 and February, 2019. There was no restriction regarding the year of publication and language. The combination of the descriptors used for this systematic review was: Migraine AND Magnetic resonance spectroscopy [MESH]. The inclusion criteria chosen were: original articles using 31P-MRS in individuals diagnosed with migraine (with and/or without aura); studies with adults between 18 and 60 years of age diagnosed with episodic or chronic migraine; with control group of individuals without migraine and without pathologies or conditions that would interfere in the results. Excluded were articles: incomplete or unpublished; animal studies; and research protocol articles. Results: Of the 319 articles found, nine were selected. The sample totaled 216 individuals with migraine (53.7% without aura) and 233 healthy individuals in the control group. It was verified a reduction of phosphocreatine, phosphorylation potential, Mg2+ and ATP, whereas it was observed increase of inorganic phosphate and ADP. Conclusion: There are alterations in cerebral energetic metabolism in individuals with migraine, revealing mitochondrial dysfunction. However, it is needed more studies with higher quality and analysis of the relationships with the socio-demographic and clinical variables. 


1989 ◽  
Vol 70 (4) ◽  
pp. 612-618 ◽  
Author(s):  
Isabelle M. Germano ◽  
Lawrence H. Pitts ◽  
Isabelle Berry ◽  
Michael Moseley

✓ Recent advances in magnetic resonance (MR) imaging and MR spectroscopy (MRS) allow the noninvasive in vivo study of a variety of anatomical, physiological, and biochemical alterations that may occur in different cerebral pathologies. The authors have investigated the use of MR imaging and MRS to monitor the evolution of experimental focal cerebral ischemia in rats. Permanent focal cerebral ischemia was induced in 36 rats, and 12 normal rats were used as a control group. Changes in high-energy phosphate metabolites were followed in vivo using MRS during the 1st hour and at 3 and 6 hours after ischemic insult. Changes in in vivo MR images were evaluated at 1, 3, 6, 12, and 24 hours after ischemic insult. Significant decreases (p < 0.05) in phosphocreatine/inorganic phosphate ratios and intracellular pH values occurred immediately after the induction of ischemia. The presence of an infarcted area seen on MR images was a constant finding at 3 hours after ischemic insult, and was well defined and localized at 12 and 24 hours. The location of areas of infarction seen on MR images correlated well with areas identified histopathologically. The T1 and T2 MR relaxation times were significantly increased 3 hours after ischemic insult and remained prolonged for at least 24 hours. The results show that MR imaging is a sensitive method to measure cerebral infarction, and that MRS is a sensitive measure of changes that occur in the early phases of ischemia, perhaps when cellular changes may still be reversible. At 3 and 6 hours after the ischemic insult, however, 31P-MRS spectra may appear to be “normal” despite the presence of well-documented areas of infarction.


2020 ◽  
Vol 53 (6) ◽  
pp. 359-365 ◽  
Author(s):  
Diogo G. Corrêa ◽  
Eelco van Duinkerken ◽  
Nicolle Zimmermann ◽  
Rochele P. Fonseca ◽  
Emerson L. Gasparetto

Abstract Objective: We aimed to evaluate whether human immunodeficiency virus (HIV)-positive patients with and without clinically significant memory deficits and healthy control participants differ on in vivo hydrogen-1 magnetic resonance spectroscopy (H-MRS) in the posterior cingulate gyri. Materials and Methods: In total, 21 HIV-positive patients with memory deficit (HIV+wMD) were compared with 15 HIV-positive patients without memory deficit (HIV+wOMD) and 22 sex-, age-, and education-matched control participants. Memory impairments were classified based on the participants’ performance on the Rey Auditory Verbal Learning Test. Short echo time (30 ms), single-voxel H-MRS was performed using a 1.5-T magnetic resonance scanner. Results: The HIV+wMD and HIV+wOMD groups had higher choline/creatine ratio in the posterior cingulate gyri than the control group. There were no significant metabolite ratio differences between the HIV+wMD and HIV+wOMD groups. Conclusion: HIV-positive patients with and without memory deficits had significantly higher choline/creatine ratios than controls in the posterior cingulate gyri, which may reflect cerebral inflammation, altered cell membrane metabolism, microgliosis, and/or astrocytosis.


Author(s):  
D.J. Meyerhoff

Magnetic Resonance Imaging (MRI) observes tissue water in the presence of a magnetic field gradient to study morphological changes such as tissue volume loss and signal hyperintensities in human disease. These changes are mostly non-specific and do not appear to be correlated with the range of severity of a certain disease. In contrast, Magnetic Resonance Spectroscopy (MRS), which measures many different chemicals and tissue metabolites in the millimolar concentration range in the absence of a magnetic field gradient, has been shown to reveal characteristic metabolite patterns which are often correlated with the severity of a disease. In-vivo MRS studies are performed on widely available MRI scanners without any “sample preparation” or invasive procedures and are therefore widely used in clinical research. Hydrogen (H) MRS and MR Spectroscopic Imaging (MRSI, conceptionally a combination of MRI and MRS) measure N-acetylaspartate (a putative marker of neurons), creatine-containing metabolites (involved in energy processes in the cell), choline-containing metabolites (involved in membrane metabolism and, possibly, inflammatory processes),


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