scholarly journals Magnetic resonance spectroscopy analysis of intramyocellular lipid composition in lipodystrophic patients and athletes

2018 ◽  
Author(s):  
David B Savage ◽  
Laura Watson ◽  
Katie Carr ◽  
Claire Adams ◽  
Soren Brage ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Tibialis Anterior ◽  
Saturation Index ◽  
Resonance Spectroscopy ◽  
Intramyocellular Lipid ◽  
Age And Gender ◽  
Insulin Resistant ◽  
And Gender

AbstractContextParadoxically, intramyocellular lipid (IMCL) accumulation has been linked to both insulin-resistant and to insulin-sensitive (athletes) states. The composition of this lipid store is unknown in these states.Design and MethodsWe used a recently validated and potentially widely applicable 1H magnetic resonance spectroscopy method to compare the compositional saturation index (CH2:CH3 ratio) and concentration independent of composition (CH3) of intramyocellular lipid in the soleus and tibialis anterior muscles of 16 female insulin-resistant lipodystrophic patients with that of age- and gender-matched athletes (n=14) and healthy controls (n = 41).Main OutcomeIMCL compositional saturation index (CH2:CH3 ratio).ResultsThe IMCL CH2:CH3 ratio was significantly higher in both muscles of the lipodystrophic patients compared with age- and gender-matched controls but not compared to athletes. IMCL CH2:CH3 was dependent on IMCL concentration in the controls and after adjusting the composition index for quantity (CH2:CH3adj) was able to distinguish patients from athletes. With groups pooled, this CH2:CH3adj marker had the strongest relation to insulin resistance (HOMA-IR) compared to other measures of lipid concentration and composition, especially in the soleus muscle. Contrary to the ‘athlete’s paradox’, IMCL in athletes was similar in tibialis anterior (p>0.05) and significantly lower in the soleus (p < 0.004) compared to both controls and patients.ConclusionsThe IMCL saturation index adjusted for quantity, which likely reflects accumulation of saturated IMCL, is more closely associated with insulin resistance than concentration alone.

scholarly journals Increased intramyocellular lipid accumulation in HIV-infected women with fat redistribution

2006 ◽  
Vol 100 (2) ◽  
pp. 609-614 ◽  
Author(s):  
Martin Torriani ◽  
Bijoy J. Thomas ◽  
Robert B. Barlow ◽  
Jamie Librizzi ◽  
Sara Dolan ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Body Composition ◽  
Magnetic Resonance ◽  
Subcutaneous Fat ◽  
Abdominal Fat ◽  
Whole Body ◽  
Resonance Spectroscopy ◽  
Intramyocellular Lipid ◽  
Fat Redistribution ◽  
Visceral Abdominal Fat

The human immunodeficiency virus (HIV)-lipodystrophy syndrome is associated with fat redistribution and metabolic abnormalities, including insulin resistance. Increased intramyocellular lipid (IMCL) concentrations are thought to contribute to insulin resistance, being linked to metabolic and body composition variables. We examined 46 women: HIV infected with fat redistribution ( n = 25), and age- and body mass index-matched HIV-negative controls ( n = 21). IMCL was measured by 1H-magnetic resonance spectroscopy, and body composition was assessed with computed tomography, dual-energy X-ray absorptiometry (DEXA), and magnetic resonance imaging. Plasma lipid profile and markers of glucose homeostasis were obtained. IMCL was significantly increased in tibialis anterior [135.0 ± 11.5 vs. 85.1 ± 13.2 institutional units (IU); P = 0.007] and soleus [643.7 ± 61.0 vs. 443.6 ± 47.2 IU, P = 0.017] of HIV-infected subjects compared with controls. Among HIV-infected subjects, calf subcutaneous fat area (17.8 ± 2.3 vs. 35.0 ± 2.5 cm2, P < 0.0001) and extremity fat by DEXA (11.8 ± 1.1 vs. 15.6 ± 1.2 kg, P = 0.024) were reduced, whereas visceral abdominal fat (125.2 ± 11.3 vs. 74.4 ± 12.3 cm2, P = 0.004), triglycerides (131.1 ± 11.0 vs. 66.3 ± 12.3 mg/dl, P = 0.0003), and fasting insulin (10.8 ± 0.9 vs. 7.0 ± 0.9 μIU/ml, P = 0.004) were increased compared with control subjects. Triglycerides ( r = 0.39, P = 0.05) and extremity fat as percentage of whole body fat by DEXA ( r = −0.51, P = 0.01) correlated significantly with IMCL in the HIV but not the control group. Extremity fat (β = −633.53, P = 0.03) remained significantly associated with IMCL among HIV-infected patients, controlling for visceral abdominal fat, abdominal subcutaneous fat, and antiretroviral medications in a regression model. These data demonstrate increased IMCL in HIV-infected women with a mixed lipodystrophy pattern, being most significantly associated with reduced extremity fat. Further studies are necessary to determine the relationship between extremity fat loss and increased IMCL in HIV-infected women.

Metabolite changes and gender differences in schizophrenia using 3-Tesla proton magnetic resonance spectroscopy (1H-MRS)

2009 ◽  
Vol 108 (1-3) ◽  
pp. 69-77 ◽  
Author(s):  
Shin'Ya Tayoshi ◽  
Satsuki Sumitani ◽  
Kyoko Taniguchi ◽  
Sumiko Shibuya-Tayoshi ◽  
Shusuke Numata ◽  
...  
Keyword(s):  
Gender Differences ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Proton Magnetic Resonance ◽  
Proton Magnetic Resonance Spectroscopy ◽  
3 Tesla ◽  
Resonance Spectroscopy ◽  
1H Mrs ◽  
And Gender

scholarly journals Insulin resistance, intramyocellular lipid content, and plasma adiponectin in patients with type 1 diabetes

2003 ◽  
Vol 285 (6) ◽  
pp. E1174-E1181 ◽  
Author(s):  
Gianluca Perseghin ◽  
Guido Lattuada ◽  
Massimo Danna ◽  
Lucia Piceni Sereni ◽  
Paola Maffi ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Type 1 Diabetes ◽  
Resonance Spectroscopy ◽  
Metabolic Clearance ◽  
Intramyocellular Lipid ◽  
Euglycemic Hyperinsulinemic Clamp ◽  
Plasma Adiponectin ◽  
Insulin Resistant ◽  
Chronic Hyperglycemia

Insulin resistance is a key pathogenic factor of type 2 diabetes (T2DM); in contrast, in type 1 diabetes (T1DM) it is considered a secondary alteration. Increased intramyocellular lipid (IMCL) content accumulation and reduced plasma adiponectin were suggested to be pathogenic events of insulin resistance in T2DM. This study was designed to assess whether IMCL content and plasma adiponectin were also associated with the severity of insulin resistance in T1DM. We studied 18 patients with T1DM, 7 older and overweight/obese patients with T2DM, and 15 nondiabetic, insulin-resistant offspring of T2DM parents (OFF) and 15 healthy individuals (NOR) as appropriate control groups matched for anthropometric features with T1DM patients by means of the euglycemic hyperinsulinemic clamp combined with the infusion of [6,6-2H2]glucose and 1H magnetic resonance spectroscopy of the calf muscles. T1DM and T2DM patients showed reduced insulin-stimulated glucose metabolic clearance rate (MCR: 5.1 ± 0.6 and 3.2 ± 0.8 ml · kg–1 · min–1) similar to OFF (5.3 ± 0.4 ml · kg–1 · min–1) compared with NOR (8.5 ± 0.5 ml · kg–1 · min–1, P < 0.001). Soleus IMCL content was increased in T1DM (112 ± 15 AU), T2DM (108 ± 10 AU) and OFF (82 ± 13 AU) compared with NOR (52 ± 7 AU, P < 0.05) and the result was inversely proportional to the MCR ( R2 = 0.27, P < 0.001); an association between IMCL content and Hb A1c was found only in T1DM ( R2 = 0.57, P < 0.001). Fasting plasma adiponectin was reduced in T2DM (7 ± 1 μg/ml, P = 0.01) and OFF (11 ± 1 μg/ml, P = 0.03) but not in T1DM (25 ± 6 μg/ml), whose plasma level was increased with respect to both OFF ( P = 0.03) and NOR (16 ± 2 μg/ml, P = 0.05). In conclusion, in T1DM, T2DM, and OFF, IMCL content was associated with insulin resistance, demonstrating that IMCL accretion is a marker of insulin resistance common to both primary genetically determined and secondary metabolic (chronic hyperglycemia) alterations. The increased adiponectin levels in insulin-resistant patients with T1DM, in contrast to the reduced levels found in patients with T2DM and in OFF, demonstrated that the relationship of adiponectin to insulin resistance in humans is still unclear.

Magnetic Resonance Spectroscopy Facilitates Assessment of Intramyocellular Lipid Changes: a Preliminary Short-Term Study Following Biliopancreatic Diversion

2005 ◽  
Vol 15 (9) ◽  
pp. 1233-1237 ◽  
Author(s):  
Gian Franco Adami ◽  
Roberto Carlo Parodi ◽  
Francesco Papadia ◽  
Giuseppe Marinari ◽  
Giovanni Camerini ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Biliopancreatic Diversion ◽  
Resonance Spectroscopy ◽  
Intramyocellular Lipid ◽  
Short Term ◽  
Term Study ◽  
Short Term Study

scholarly journals Intramuscular Glycogen and Intramyocellular Lipid Utilization during Prolonged Exercise and Recovery in Man: A 13C and 1H Nuclear Magnetic Resonance Spectroscopy Study1

2000 ◽  
Vol 85 (2) ◽  
pp. 748-754
Author(s):  
Martin Krssak ◽  
Kitt Falk Petersen ◽  
Raynald Bergeron ◽  
Thomas Price ◽  
Didier Laurent ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Muscle Glycogen ◽  
Prolonged Exercise ◽  
Glycogen Content ◽  
Muscle Group ◽  
Resonance Spectroscopy ◽  
Intramyocellular Lipid ◽  
Lipid Utilization ◽  
Forearm Muscle

Depletion of muscle glycogen is considered a limiting performance factor during prolonged exercise, whereas the role of the intramyocellular lipid (IMCL) pool is not yet fully understood. We examined 1) intramyocellular glycogen and lipid utilization during prolonged exercise, 2) resynthesis of muscle glycogen and lipids during recovery, and 3) changes in glycogen content between nonexercising and exercising muscles during recovery. Subjects ran on a treadmill at submaximal intensity until exhaustion. Glycogen concentrations were assessed in thigh, calf, and nonexercising forearm muscle, and IMCL content was measured in soleus muscle using magnetic resonance spectroscopy techniques. At the time of exhaustion, glycogen depletion was 2-fold greater in calf than in thigh muscles, but a significant amount of glycogen was left in both leg muscles. The glycogen concentration in nonexercising forearm muscle decreased during the initial 5 h of recovery to 73% of the baseline value. During the exercise, the IMCL content decreased to 67% and subsequently during recovery increased to 83% of the baseline value. In summary, we found during prolonged running 1) significantly greater muscle glycogen utilization in the calf muscle group than in the thigh muscle group, 2) significant utilization of IMCL in the soleus muscle, and 3) a decrease in glycogen content in nonexercising muscle and an increase in glycogen content in recovering muscles during the postexercise phase. These latter data are consistent with the hypothesis that there is transfer of glycogen by the glucose→lactate and the glucose→alanine cycle from the resting muscle (forearm) to recovering muscles (thigh and calf) after running exercise .

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