Owing to the worldwide obesity epidemic and the sedentary lifestyle in industrialized countries, the number of people with metabolic diseases is explosively increasing. Magnetic resonance spectroscopy (MRS), which is fundamentally similar to magnetic resonance imaging, can detect metabolic changes in vivo noninvasively. With its noninvasive nature, 1H, 13C and 31P MRS are being actively utilized in clinical and biomedical metabolic studies to detect lipids and important metabolites without ionizing radiation. 1H MRS can quantify lipid content in liver and muscle and can detect other metabolites, such as 2-hydroxyglutarate, in vivo. Of interest, many studies have indicated that hepatic and intramyocellular lipid content is inversely correlated with insulin sensitivity in humans. Thus, lipid content can be utilized as an in vivo biomarker for detecting early insulin resistance. Employing 13C MRS, hepatic glycogen synthesis and breakdown can be directly detected, whereas 31P MRS provides in vivo adenosine triphosphate (ATP) synthesis rates by saturation transfer methods in addition to ATP content. These in vivo data can be very difficult to assess by other methods and offer a critical piece of metabolic information. To aid the reader in understanding these new methods, fundamentals of MRS are described in this review in addition to promising future applications of MRS and its limitations.
Carbon-13 Magnetic Resonance Spectroscopy ; Humans ; Magnetic Resonance Imaging/methods ; *Magnetic Resonance Spectroscopy/methods ; Metabolic Diseases/*diagnosis ; Phosphorus Isotopes ; Protons

Electron Spin Resonance Spectroscopy ; Magnetic Resonance Spectroscopy ; Models, Molecular ; Protein Structure, Tertiary ; Proteins ; chemistry

OBJECTIVES: To study the urinary metabolic profile in rats with deep venous thrombosis （DVT） based on metabolomics and to screen out small molecular biomarkers for the diagnosis and forensic identification of DVT. METHODS: Inferior vena cava of rats was ligated to construct DVT models. The rats were randomly divided into three groups： DVT, sham, and control groups, 10 in each group. The urine of DVT and sham rats was collected during 24 hours in the metabolic cage at 48 hours after operating, meanwhile, 24 hours urine was collected in control group. The metabolic profile was analyzed by nuclear magnetic resonance. SIMCA-P 14.1 software was used for pattern recognition. The variable importance in projection （VIP） value from orthogonal PLS-DA （OPLS-DA） model combined with Mann-Whitney U test were used to search the different metabolites in the urine. RESULTS: The metabolic profiles of urine from DVT, sham, and control groups had significant differences. The DVT, sham, and control groups could be distinguished by the partial least squares method-discriminant analysis （PLS-DA） model. Compared with the urine of the rats in control groups, the levels of leucine, glutamine, creatine, creatinine and sucrose in the urine of DVT rats were up-regulated, and the levels of 3-hydroxybutyrate, lactate, acetone, α-oxoglutarate, citrate and hippurate were down-regulated. CONCLUSIONS The different metabolites in the urine of DVT rats are expected to become its candidate biomarkers. The results can provide a research basis for the diagnosis, treatment and forensic identification of DVT.
Animals ; Biomarkers/blood* ; Discriminant Analysis ; Humans ; Magnetic Resonance Spectroscopy/methods* ; Metabolome ; Metabolomics/methods* ; Nuclear Magnetic Resonance, Biomolecular/methods* ; Rats ; Rats, Sprague-Dawley ; Urine/chemistry* ; Venous Thrombosis/urine*

The diagnostic and prognostic potential of an onco-metabolite, 2-hydroxyglutarate (2HG) as a proton magnetic resonance spectroscopy (1H-MRS) detectable biomarker of the isocitrate dehydrogenase (IDH)-mutated (IDH-MT) gliomas has drawn attention of neuroradiologists recently. However, due to severe spectral overlap with background signals, quantification of 2HG can be very challenging. In this technical review for neuroradiologists, first, the biochemistry of 2HG and its significance in the diagnosis of IDH-MT gliomas are summarized. Secondly, various 1H-MRS methods used in the previous studies are outlined. Finally, wereview previous in vivo studies, and discuss the current status of 1H-MRS in the diagnosis of IDH-MT gliomas.
Biochemistry ; Diagnosis ; Glioma* ; Isocitrate Dehydrogenase ; Magnetic Resonance Spectroscopy ; Proton Magnetic Resonance Spectroscopy* ; Protons*

Based on¹ H-NMR metabonomics,the effects of Codonopsis pilosula,rice-fried C. pilosula and honey-fried C. pilosula on spleen-asthenia rats were compared,and the mechanism was discussed in this study. The rat model of spleen deficiency was established by weight-bearing swimming and fasting every other day. The effects of different processed products of C. pilosula on the body weight and swimming time of rats were observed. At the end of administration,the gastrocnemius muscle of the right leg of rats was collected and detected by¹ H-NMR,and the mechanism of different processed products of C. pilosula in improving spleen deficiency was preliminarily investigated by multivariate statistical analysis. The results showed that C. pilosula,honey-fried C. pilosula and rice-fried C. pilosula could significantly prolong the swimming time( P<0. 05). There was no significant difference in the body weight of rats with spleen deficiency. The results of metabonomics showed that honey-processed C. pilosula could significantly decrease levels of leucine,isoleucine,alanine,acetate,glutamate,succinate,anserine,dimethylamine,dimethylglycine,creatine,phosphorylcholine,glycerophosphorylcholine,taurine,inosine,fumate,hypoxanthine and lactate,but increase levels of glucose,glycine,compared with model group. Therefore,honey-fried C. pilosula has the best efficacy on spleen deficiency syndrome in rats by regulating glycometabolism,amino acid metabolism,lipid metabolism and nucleotide metabolism.
Animals ; Codonopsis ; Magnetic Resonance Spectroscopy ; Metabolomics ; Proton Magnetic Resonance Spectroscopy ; Rats ; Spleen

OBJECTIVES: To explore the metabolite characteristics in medial prefrontal cortex (mPFC) by METHODS: A total of 46 patients with the first-episode schizophrenia (FES), 49 people with clinical high risk (CHR), 61 people with genetic high risk (GHR), and 58 healthy controls (HC) were enrolled. The levels of N-acetylaspartylglutamate+N-acetylaspartate (tNAA), choline-containing compounds (Cho) and myo-inositol (MI), glutamate+glutamine (Glx) in medial prefrontal cortex were measured by single-voxel RESULTS: There were significant differences in Glx, tNAA, and MI concentrations among 4 groups (all CONCLUSIONS The decreased levels of MI and Glx in the FES patients suggest that there may be glial functional damage and glutamatergic transmitter dysfunction in the early stage of the disease. The compensatory increase of metabolites may be a protective factor for schizophrenia in the genetic individuals.
Aspartic Acid ; Glutamic Acid ; Glutamine ; Humans ; Magnetic Resonance Imaging ; Magnetic Resonance Spectroscopy ; Proton Magnetic Resonance Spectroscopy ; Schizophrenia

OBJECTIVETo investigate the changes of cerebral metabolism in rabbit model of hemorrhagic shock by using proton magnetic resonance spectroscopy(PMRS).

METHODSTen New Zealand white rabbits were used for construction of the model of acute hemorrhagic anemia. 1H-MRS was performed before and at the time-peint of 30, 90, and 180 min after hemorrhagic shock. The concentrations of NAA, Cr, Cho, Lac, and NAA/Cr and Cho/Cr ratios were estimated.

RESULTSHemorrhagic shock was associated with significant reductions in red blood cell count, hemoglobin level, hematocrit, pH, and PaCO, and elevations of blood lactate and PaO. The ratios of NAA/Cr at 30 min, 90 min and 180 min after shock were (1.50±0.09), (1.37±0.09) and (1.27±0.10), respectively, which were significantly lower than those before shock (2.11±0.16) (P <0.05) (1.16±0.05) and (0.97±0.04) at 30 min and 90 min after shock, respectively, which were significantly lower than those pre-shock (1.38±0.08) (P <0.05). The ratis of Cho/Cr at 30 min and 90 min were (1.16±0.05) and (0.97±0.04), respectively, which were significantly lower than those before shock (1.38±0.08) (P <0.05).

CONCLUSIONMRS can noninvasively and dynamically detect brean metabolic changes in early hemorrhagic shock, and has positive significance for early diagnosis and prognosis assessment of hemorrhagic shock.

Animals ; Aspartic Acid ; Brain ; Choline ; Disease Models, Animal ; Magnetic Resonance Spectroscopy ; Proton Magnetic Resonance Spectroscopy ; Protons ; Rabbits ; Shock, Hemorrhagic

The present study established a quality evaluation method for ginsenoside reference substances based on quantitative nuclear magnetic resonance(qNMR) spectroscopy. ~1H-NMR spectra were collected on Bruker Avance Ⅲ 500 MHz NMR spectrometer equipped with a 5 mm BBO probe. The acquire parameters were set up as follows: pulse sequence of 30°, D_1=20 s, probe temperature= 303 K, and the scan number = 32. Dimethyl terephthalate, a high-quality ~1H-qNMR standard, was used as the internal standard and measured by the absolute quantitative method. Methyl peaks of comparatively good sensitivity were selected for quantification, and linear fitting deconvolution was adopted to improve the accuracy of integration results. The qNMR spectroscopy-based method was established and validated, which was then used for the quality evaluation of ginsenoside Rg_1, ginsenoside Re, ginsenoside Rb_1, ginsenoside Rd, and notoginsenoside R_1. The results suggested that the content of these ginsenoside reference standards obtained from the qNMR spectroscopy-based method was lower than that detected by the normalization method in HPLC provided by the manufacturers. In conclusion, the qNMR spectroscopy-based method can ensure the quality of ginsenoside reference substances and provide powerful support for the accurate quality evaluation of Chinese medicine and its preparations. The qNMR spectroscopy-based method is simple, rapid, and accurate, which can be developed for the quantitative assay of Chinese medicine standard references.
Chromatography, High Pressure Liquid/methods* ; Ginsenosides/analysis* ; Magnetic Resonance Spectroscopy/methods* ; Proton Magnetic Resonance Spectroscopy ; Reference Standards

OBJECTIVE: To noninvasively assess the neurodegenerative changes in the brain of patients with Niemann-Pick type C (NPC) disease by measuring the lesion tissue with the iterative decomposition of water and fat with echo asymmetry and least square estimation-iron quantification (IDEAL-IQ). MATERIALS AND METHODS: Routine brain MRI, IDEAL-IQ and 1H-proton magnetic resonance spectroscopy (1H-MRS, served as control) were performed on 12 patients with type C Niemann-Pick disease (4 males and 8 females; age range, 15–61 years; mean age, 36 years) and 20 healthy subjects (10 males and 10 females; age range, 20–65 years; mean age, 38 years). The regions with lesion and the normal appearing regions (NARs) of patients were measured and analyzed based on the fat/water signal intensity on IDEAL-IQ and the lipid peak on 1H-MRS. RESULTS: Niemann-Pick type C patients showed a higher fat/water signal intensity ratio with IDEAL-IQ on T2 hyperintensity lesions and NARs (3.7–4.9%, p < 0.05 and 1.8–3.0%, p < 0.05, respectively), as compared to healthy controls (HCs) (1.2–2.3%). After treatment, the fat/water signal intensity ratio decreased (2.2–3.4%), but remained higher than in the HCs (p < 0.05). The results of the 1H-MRS measurements showed increased lipid peaks in the same lesion regions, and the micro-lipid storage disorder of NARs in NPC patients was detectable by IDEAL-IQ instead of 1H-MRS. CONCLUSION: The findings of this study suggested that IDEAL-IQ may be useful as a noninvasive and objective method in the evaluation of patients with NPC; additionally, IDEAL-IQ can be used to quantitatively measure the brain parenchymal adipose content and monitor patient follow-up after treatment of NPC.
Brain ; Female ; Follow-Up Studies ; Healthy Volunteers ; Humans ; Magnetic Resonance Imaging ; Magnetic Resonance Spectroscopy ; Male ; Methods ; Niemann-Pick Diseases ; Proton Magnetic Resonance Spectroscopy ; Water

This study is to compare the accuracy of evaluation regarding the volume of the prostate, which three-dimensional volume rendering was produced the shape of protrusion, by measuring two kinds of craniocaudal length from the top of the protrusion and from the exclusion of the protrusion as the starting points. For the imaginary protrusion prostate models, total of 10 models were roughly made by using devils-tongue jelly and changing each of the 10 ml of capacity from 10 ml to 100 ml. For the protrusion prostate models aimed at estimating the real volume, through 64 cannel computed tomography (CT) and 3.0 tesla magnetic resonance image (MRI) were conducted by planimetry technique from three-dimensional volume rendering. And then we performed to evaluate on significance of these volumes by wilcoxon signed rank test. Also the obtained volumes data by ellipsoid volume formula were measured the volume of protrusion prostate models two times with each method using the two kinds of craniocaudal length from top of the protrusion and from exclusion of the protrusion as the starting points. Finally, the significance of differences using wilcoxon signed rank test was evaluated between the real volume by planimetry technique and the measured volume by ellipsoid volume formula from three-dimensional volume rendering. The average of the protrusion length on the models was 0.90+/-0.18 mm in CT and was 0.75+/-0.11 mm in MRI. There were not statistically significant difference between MRI and CT from the volume of protrusion prostate models (p=0.414). In MRI (p=0.139) and CT (p=0.057), there were not statistically significant difference between the real volume by planimetry technique and the measured volume by ellipsoid volume from exclusion of the protrusion as the starting points. While, there were statistically significant difference between the real volume by planimetry technique and the measured volume by ellipsoid volume from top of the protrusion as the starting points in MRI (p=0.005) and CT (p=0.005). For the accurate measurement of the protrusion prostate models, the craniocaudal length of the prostate should be measured from the exclusion of the protrusion as the starting points.
Magnetic Resonance Spectroscopy ; Prostate