scholarly journals Exercise Restores Skeletal Muscle Glucose Delivery But Not Insulin-Mediated Glucose Transport and Phosphorylation in Obese Subjects

2006 ◽  
Vol 91 (9) ◽  
pp. 3394-3403 ◽  
Author(s):  
L. Slimani ◽  
V. Oikonen ◽  
K. Hällsten ◽  
N. Savisto ◽  
J. Knuuti ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Positron Emission Tomography ◽  
Glucose Transport ◽  
Oxidative Capacity ◽  
Emission Tomography ◽  
Glucose Disposal ◽  
Oxidative Potential ◽  
Positron Emission ◽  
Significant Difference ◽  
Obese Subjects

Abstract Context/Objective: Insulin resistance in obese subjects results in the impaired disposal of glucose by skeletal muscle. The current study examined the effects of insulin and/or exercise on glucose transport and phosphorylation in skeletal muscle and the influence of obesity on these processes. Subjects/Methods: Seven obese and 12 lean men underwent positron emission tomography with 2-deoxy-2-[18F]fluoro-d-glucose in resting and isometrically exercising skeletal muscle during normoglycemic hyperinsulinemia. Data were analyzed by two-tissue compartmental modeling. Perfusion and oxidative capacity were measured during insulin stimulation by [15O]H2O and [15O]O2. Results: Exercise increased glucose fractional uptake (K), inward transport rate (K1), and the k3 parameter, combining transport and intracellular phosphorylation, in lean and obese subjects. In each group, there was no statistically significant difference between plasma flow and K1. At rest, a significant defect in K1 (P = 0.0016), k3 (P = 0.016), and K (P = 0.022) was found in obese subjects. Exercise restored K1, improved but did not normalize K (P = 0.03 vs. lean), and did not ameliorate the more than 60% relative impairment in k3 in obese individuals (P = 0.002 vs. lean). The glucose oxidative potential tended to be reduced by obesity. Conclusions/Interpretation: The study indicates that exercise restores the impairment in insulin-mediated skeletal muscle perfusion and glucose delivery associated with obesity but does not normalize the defect involving the proximal steps regulating glucose disposal in obese individuals. Our data support the use of 2-deoxy-2-[18F]fluoro-d-glucose-positron emission tomography in the dissection between substrate supply and intrinsic tissue metabolism.

scholarly journals Quantitative Assessment of Glucose Transport in Human Skeletal Muscle: Dynamic Positron Emission Tomography Imaging of [O-Methyl-11C]3-O-Methyl-d-Glucose

2005 ◽  
Vol 90 (3) ◽  
pp. 1752-1759 ◽  
Author(s):  
Alessandra Bertoldo ◽  
Julie Price ◽  
Chet Mathis ◽  
Scott Mason ◽  
Daniel Holt ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Positron Emission Tomography ◽  
Glucose Transport ◽  
Pet Imaging ◽  
Human Skeletal Muscle ◽  
Insulin Infusion ◽  
Emission Tomography ◽  
Dynamic Pet ◽  
Positron Emission ◽  
18F Fdg

Insulin-stimulated glucose transport in skeletal muscle is regarded as a key determinant of insulin sensitivity, yet isolation of this step for quantification in human studies is a methodological challenge. One notable approach is physiological modeling of dynamic positron emission tomography (PET) imaging using 2-[18-fluoro]2-deoxyglucose ([18F]FDG); however, this has a potential limitation in that deoxyglucose undergoes phosphorylation subsequent to transport, complicating separate estimations of these steps. In the current study we explored the use of dynamic PET imaging of [11C]3-O-methylglucose ([11C]3-OMG), a glucose analog that is limited to bidirectional glucose transport. Seventeen lean healthy volunteers with normal insulin sensitivity participated; eight had imaging during basal conditions, and nine had imaging during euglycemic insulin infusion at 30 mU/min·m2. Dynamic PET imaging of calf muscles was conducted for 90 min after the injection of [11C]3-OMG. Spectral analysis of tissue activity indicated that a model configuration of two reversible compartments gave the strongest statistical fit to the kinetic pattern. Accordingly, and consistent with the structure of a model previously used for [18F]FDG, a two-compartment model was applied. Consistent with prior [18F]FDG findings, insulin was found to have minimal effect on the rate constant for movement of [11C]3-OMG from plasma to tissue interstitium. However, during insulin infusion, a robust and highly significant increase was observed in the kinetics of inward glucose transport; this and the estimated tissue distribution volume for [11C]3-OMG increased 6-fold compared with basal conditions. We conclude that dynamic PET imaging of [11C]3-OMG offers a novel quantitative approach that is both chemically specific and tissue specific for in vivo assessment of glucose transport in human skeletal muscle.

scholarly journals Glucose Transport and Phosphorylation in Skeletal Muscle in Obesity: Insight from a Muscle-Specific Positron Emission Tomography Model

2003 ◽  
Vol 88 (3) ◽  
pp. 1271-1279 ◽  
Author(s):  
Katherine V. Williams ◽  
Alessandra Bertoldo ◽  
Bruno Mattioni ◽  
Julie C. Price ◽  
Claudio Cobelli ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Positron Emission Tomography ◽  
Glucose Transport ◽  
Emission Tomography ◽  
Positron Emission

Usefulness of positron emission tomography for differentiating gliomas according to the 2016 World Health Organization classification of tumors of the central nervous system

2020 ◽  
Vol 133 (4) ◽  
pp. 1010-1019 ◽  
Author(s):  
Hiroaki Takei ◽  
Jun Shinoda ◽  
Soko Ikuta ◽  
Takashi Maruyama ◽  
Yoshihiro Muragaki ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Pet Imaging ◽  
Who Classification ◽  
Standardized Uptake Value ◽  
Emission Tomography ◽  
World Health ◽  
Pet Tracers ◽  
Positron Emission ◽  
Significant Difference ◽  
The Mean

OBJECTIVEPositron emission tomography (PET) is important in the noninvasive diagnostic imaging of gliomas. There are many PET studies on glioma diagnosis based on the 2007 WHO classification; however, there are no studies on glioma diagnosis using the new classification (the 2016 WHO classification). Here, the authors investigated the relationship between uptake of 11C-methionine (MET), 11C-choline (CHO), and 18F-fluorodeoxyglucose (FDG) on PET imaging and isocitrate dehydrogenase (IDH) status (wild-type [IDH-wt] or mutant [IDH-mut]) in astrocytic and oligodendroglial tumors according to the 2016 WHO classification.METHODSIn total, 105 patients with newly diagnosed cerebral gliomas (6 diffuse astrocytomas [DAs] with IDH-wt, 6 DAs with IDH-mut, 7 anaplastic astrocytomas [AAs] with IDH-wt, 24 AAs with IDH-mut, 26 glioblastomas [GBMs] with IDH-wt, 5 GBMs with IDH-mut, 19 oligodendrogliomas [ODs], and 12 anaplastic oligodendrogliomas [AOs]) were included. All OD and AO patients had both IDH-mut and 1p/19q codeletion. The maximum standardized uptake value (SUV) of the tumor/mean SUV of normal cortex (T/N) ratios for MET, CHO, and FDG were calculated, and the mean T/N ratios of DA, AA, and GBM with IDH-wt and IDH-mut were compared. The diagnostic accuracy for distinguishing gliomas with IDH-wt from those with IDH-mut was assessed using receiver operating characteristic (ROC) curve analysis of the mean T/N ratios for the 3 PET tracers.RESULTSThere were significant differences in the mean T/N ratios for all 3 PET tracers between the IDH-wt and IDH-mut groups of all histological classifications (p < 0.001). Among the 27 gliomas with mean T/N ratios higher than the cutoff values for all 3 PET tracers, 23 (85.2%) were classified into the IDH-wt group using ROC analysis. In DA, there were no significant differences in the T/N ratios for MET, CHO, and FDG between the IDH-wt and IDH-mut groups. In AA, the mean T/N ratios of all 3 PET tracers in the IDH-wt group were significantly higher than those in the IDH-mut group (p < 0.01). In GBM, the mean T/N ratio in the IDH-wt group was significantly higher than that in the IDH-mut group for both MET (p = 0.034) and CHO (p = 0.01). However, there was no significant difference in the ratio for FDG.CONCLUSIONSPET imaging using MET, CHO, and FDG was suggested to be informative for preoperatively differentiating gliomas according to the 2016 WHO classification, particularly for differentiating IDH-wt and IDH-mut tumors.

Evaluation of individual skeletal muscle activity by glucose uptake during pedaling exercise at different workloads using positron emission tomography

2009 ◽  
Vol 107 (2) ◽  
pp. 599-604 ◽  
Author(s):  
Yuichi Gondoh ◽  
Manabu Tashiro ◽  
Masatoshi Itoh ◽  
Mohammad M. Masud ◽  
Hiroomi Sensui ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Positron Emission Tomography ◽  
Glucose Uptake ◽  
Muscle Activity ◽  
Rectus Femoris ◽  
Emission Tomography ◽  
Whole Body ◽  
Control Subjects ◽  
Positron Emission ◽  
Iliacus Muscle

Skeletal muscle glucose uptake closely reflects muscle activity at exercise intensity levels <55% of maximal oxygen consumption (V̇o2max). Our purpose was to evaluate individual skeletal muscle activity from glucose uptake in humans during pedaling exercise at different workloads by using [18F]fluorodeoxyglucose (FDG) and positron emission tomography (PET). Twenty healthy male subjects were divided into two groups (7 exercise subjects and 13 control subjects). Exercise subjects were studied during 35 min of pedaling exercise at 40 and 55% V̇o2max exercise intensities. FDG was injected 10 min after the start of exercise or after 20 min of rest. PET scanning of the whole body was conducted after completion of the exercise or rest period. In exercise subjects, mean FDG uptake [standardized uptake ratio (SUR)] of the iliacus muscle and muscles of the anterior part of the thigh was significantly greater than uptake in muscles of control subjects. At 55% V̇o2max exercise, SURs of the iliacus muscle and thigh muscles, except for the rectus femoris, increased significantly compared with SURs at 40% V̇o2max exercise. Our results are the first to clarify that the iliacus muscle, as well as the muscles of the anterior thigh, is the prime muscle used during pedaling exercise. In addition, the iliacus muscle and all muscles in the thigh, except for the rectus femoris, contribute when the workload of the pedaling exercise increases from 40 to 55% V̇o2max.

scholarly journals Evaluation of Skeletal Muscle Activity During Foot Training Exercises Using Positron Emission Tomography

2021 ◽  
Author(s):  
Tomoyuki Kanayama ◽  
Junsuke Nakase ◽  
Takafumi Mochizuki ◽  
Kazuki Asai ◽  
Rikuto Yoshimizu ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Positron Emission Tomography ◽  
Muscle Activity ◽  
Skeletal Muscles ◽  
Standardized Uptake Value ◽  
Emission Tomography ◽  
Abductor Hallucis ◽  
Continuous Training ◽  
Positron Emission ◽  
The Difference

Abstract The foot exercises “rock-paper-scissors” and “towel gathering” are widely used in patients with lower limb disorders; however, there are no detailed reports on muscle activity during such training. We quantitatively evaluated the difference in skeletal muscle activity between the two exercises using positron emission tomography. Eight university student athletes were included. Four participants each were assigned to the foot rock-paper-scissors and towel gathering groups. Participants in each group underwent continuous training for 15 min. They received an intravenous injection of 18F-fluorodeoxyglucose and retrained for 15 min, following which they rested for 45 min. Regions of interest were defined in 25 muscles. The standardized uptake value (SUV) in the trained limb was compared with that in the non-trained control limb. SUVs increased in four skeletal muscles (tibialis anterior, peroneus brevis, extensor hallucis brevis, and abductor hallucis) in the rock-paper-scissors group, and in four muscles (flexor digitorum longus, extensor hallucis brevis, extensor digitorum brevis, and quadratus plantae) in the towel gathering group. Thus, foot rock-paper-scissors and towel gathering affected skeletal muscles related to the medial longitudinal arch and toe grip strength, respectively. Given that the two exercises target different skeletal muscles, they should be taught and implemented according to their respective purposes.

Potential of [11C]TMSX for the evaluation of adenosine A2A receptors in the skeletal muscle by positron emission tomography

2004 ◽  
Vol 31 (7) ◽  
pp. 949-956 ◽  
Author(s):  
Kiichi Ishiwata ◽  
Masaki Mizuno ◽  
Yuichi Kimura ◽  
Kazunori Kawamura ◽  
Keiichi Oda ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Positron Emission Tomography ◽  
Emission Tomography ◽  
Adenosine A2a Receptors ◽  
A2a Receptors ◽  
Positron Emission ◽  
Adenosine A2a

29 POSITRON EMISSION TOMOGRAPHY IMAGING OF BRAIN METABOLISM AND DOPAMINERGIC NEURON DESTRUCTION IN PARKINSON'S DISEASE MODEL PIG

2017 ◽  
Vol 29 (1) ◽  
pp. 122
Author(s):  
H. J. Oh ◽  
J. Moon ◽  
G. A. Kim ◽  
S. Lee ◽  
S. H. Paek ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Dopaminergic Neuron ◽  
Brain Metabolism ◽  
Brain Research ◽  
Brain Regions ◽  
Emission Tomography ◽  
Positron Emission ◽  
Significant Difference ◽  
And Control ◽  
The Brain

Due to similarities between human and porcine, pigs have been proposed as an excellent experimental animal for human medical research. Especially in paediatric brain research, piglets share similarities with human infants in the extent of peak brain growth at the time of birth and the growth pattern of brain. Thus, these findings have supported the wider use of pigs rather than rodents in neuroscience research. Previously, we reported the production of porcine model of Parkinson's disease (PD) by nuclear transfer using donor cell that had been stably infected with lentivirus containing the human α-synuclein gene. The purpose of this study was to determine the alternation of brain metabolism and dopaminergic neuron destruction using noninvasive method in a 2-yr-old PD model and a control pig. The positron emission tomography (PET) scan was done using Biograph TruePoint40 with a TrueV (Siemens, Munich, Germany). The [18F]N-(3-fluoropropyl)-2β-carbomethoxy-3β-(4-iodophenyl) nortropane (FP-CIT) was administrated via the ear vein. Static images of the brain for 15 min were acquired from 2 h after injection. The 18F-fluorodeoxy-D-glucose PET (18F-FDG PET) images of the brain were obtained for 15 min at 45 min post-injection. Computed tomography (CT) scan and magnetic resonance imaging (MRI) were performed at the same location of the brain. In both MRI and CT images, there was no difference in brain regions between PD model and control pigs. However, administration of [18F]FP-CIT was markedly decreased in the bilateral putamen of the PD model pig compared with the control pigs. Moreover, [18F]FP-CIT administration was asymmetrical in the PD model pig but it was symmetrical in control pigs. Regional brain metabolism was also assessed and there was no significant difference in cortical metabolism of PD model and control pigs. We demonstrated that PET imaging could provide a foundation for translational Parkinson neuroimaging in transgenic pigs. In the present study, a 2-yr-old PD model pig showed dopaminergic neuron destruction in brain regions. Therefore, PD model pig expressing human α-synuclein gene would be an efficient model for human PD patients. This study was supported by Korea IPET (#311011–05–5-SB010), Research Institute for Veterinary Science, TS Corporation and the BK21 plus program.

Central D2 receptor blockade and antipsychotic effects of neuroleptics. Preliminary study with positron emission tomography

1990 ◽  
Vol 5 (4) ◽  
pp. 231-240 ◽  
Author(s):  
JL Martinot ◽  
ML Paillère-Martinot ◽  
C Loc'h ◽  
P Péron Magnan ◽  
B Mazoyer ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Dopamine Receptor ◽  
Negative Symptoms ◽  
Receptor Occupancy ◽  
Emission Tomography ◽  
Receptor Blockade ◽  
Low Doses ◽  
Receptor Density ◽  
Positron Emission ◽  
Significant Difference

SummaryThe striatal D2 receptor density/affinity index was assessed using positron emission tomography and 76Br-Bromolisuride in 15 schizophrenics, first untreated, and afterwards receiving neuroleptics, and in 14 control subjects. The patients received low or conventional doses of neuroleptics. The schizophrenics receiving low doses (n = 6) had preponderant negative symptoms. Mean D2 receptor occupancy was 24 ± 20%. Despite this weak central D2 receptor blockade, a significant decrease in negative symptoms was observed, a result consistent with the hypothesis of a disinhibitory action of some neuroleptics administered in low doses. The patients treated with conventional doses (n = 9) had mixed positive and negative symptoms, and the mean D2 receptor occupancy was 54 ± 13%. Significant decreases in positive symptoms, but also in negative symptoms, were obtained with this treatment. Before treatment, there was no significant difference in the striatal D2 receptor density/affinity index between: 1) patients and controls, 2) negative and mixed schizophrenics, and 3) the subsequent responder and non-responder patients. In addition, the D2 dopamine receptor occupancy by neuroleptics did not significantly differ in responder or nonresponder patients, suggesting that the central D2 dopamine receptor blockade is a necessary, but insufficient condition to account for the antipsychotic effect of neuroleptics.

Regional lung water and hematocrit determined by positron emission tomography

1985 ◽  
Vol 59 (3) ◽  
pp. 860-868 ◽  
Author(s):  
D. P. Schuster ◽  
M. A. Mintun ◽  
M. A. Green ◽  
M. M. Ter-Pogossian
Keyword(s):  
Positron Emission Tomography ◽  
Regional Distribution ◽  
Vertical Gradient ◽  
Emission Tomography ◽  
Lung Water ◽  
Average Value ◽  
Positron Emission ◽  
Significant Difference ◽  
Regional Basis ◽  
The Difference

We have measured with positron emission tomography (PET) the regional distribution of extravascular lung water (EVLW) and hematocrit (HctL) in normal supine dogs. H2(15)O and C15O were used as total lung water (TLW) and intravascular water (IVW) compartment labels, respectively. An additional plasma volume label (68Ga-transferrin) was used to determine regional HctL. EVLW was calculated as the difference between TLW and IVW. In 13 dogs, EVLW was relatively constant along a gravity-dependent vertical gradient, although values in the most anterior regions were statistically less (P less than 0.05) than those in more posterior ones. The average value for EVLW (13 dogs) was 14.4 +/- 2.5 ml H2O/100 ml lung. When EVLW was compared with IVW on a regional basis, the EVLW/IVW ratio decreased significantly in a gravity-dependent direction from 1.95 +/- 0.28 to 0.88 +/- 0.18. In 7 dogs, no significant difference between HctL and systemic hematocrit (average ratio 1.01 +/- 0.08) was found nor was any significant variation of HctL within the lung detected. Thus, in contrast to gravimetric techniques, a hematocrit correction does not appear to be necessary when regional EVLW is studied by PET.

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