Increased ATP synthesis might counteract hepatic lipid accumulation in acromegaly

Fellinger, Paul; Wolf, Peter; Pfleger, Lorenz; Krumpolec, Patrik; Krššák, Martin; Klavins, Kristaps; Wolfsberger, Stefan; Micko, Alexander; Carey, Patricia; Gürtl, Bettina; Vila, Greisa; Raber, Wolfgang; Fürnsinn, Clemens; Scherer, Thomas; Trattnig, S.; Kautzky‐Willer, Alexandra; Krebs, Michael; Winhofer, Yvonne

doi:10.1172/jci.insight.134638

Cited by 24 publications

(39 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…12,22 While this approach proved to be feasible in a number of patient studies, 33,34 it may not be possible in all patients, as exemplified in another study, where some volunteers had to be scanned in a supine position because of space restrictions. 35 The use of a respiratory belt or navigator for real-time or retrospective respiratory gating is also not without problems (eg loss of signal from respiratory belt or low-quality navigator signal because of B 0 and B 1 inhomogeneities, especially at high field) and leads to increased scan times. 36 For the VAPOR-STEAM spectra, the performance of the frequency correction was not optimal in 54% of the data sets for subjects with liver lipid contents lower than 2%, even though this was not directly apparent from the SNR and linewidth figures.…”

Section: Discussionmentioning

confidence: 99%

Metabolite cycled liver ¹H MRS on a 7 T parallel transmit system

et al. 2020

View full text Add to dashboard Cite

Introduction Single‐voxel 1 H MRS in body applications often suffers from respiratory and other motion induced phase and frequency shifts, which lead to incoherent averaging and hence to suboptimal results. Methods Here we show the application of metabolite cycling (MC) for liver STEAM‐localized 1 H MRS on a 7 T parallel transmit system, using eight transmit‐receive fractionated dipole antennas with 16 additional, integrated receive loops. MC‐STEAM measurements were made in six healthy, lean subjects and compared with STEAM measurements using VAPOR water suppression. Measurements were performed during free breathing and during synchronized breathing, for which the subjects did breathe in between the MRS acquisitions. Both intra‐session repeatability and inter‐session reproducibility of liver lipid quantification with MC‐STEAM and VAPOR‐STEAM were determined. Results The preserved water signal in MC‐STEAM allowed for robust phase and frequency correction of individual acquisitions before averaging, which resulted in in vivo liver spectra that were of equal quality when measurements were made with free breathing or synchronized breathing. Intra‐session repeatability and inter‐session reproducibility of liver lipid quantification were better for MC‐STEAM than for VAPOR‐STEAM. This may also be explained by the more robust phase and frequency correction of the individual MC‐STEAM acquisitions as compared with the VAPOR‐STEAM acquisitions, for which the low‐signal‐to‐noise ratio lipid signals had to be used for the corrections. Conclusion Non‐water‐suppressed MC‐STEAM on a 7 T system with parallel transmit is a promising approach for 1 H MRS applications in the body that are affected by motion, such as in the liver, and yields better repeatability and reproducibility compared with water‐suppressed measurements.

show abstract

Section: Discussionmentioning

confidence: 99%

Metabolite cycled liver ¹H MRS on a 7 T parallel transmit system

et al. 2020

View full text Add to dashboard Cite

show abstract

“…In agreement with lipidomic studies, 61,82 homozygous carriers had a greater hepatic PUI and a lower HOMA-IR compared to non-carriers despite all participants possessing hepatic steatosis. 116 From the opposing perspective, Fellinger et al 118 recently compared hepatic lipid composition between people with acromegaly and healthy controls. Notably, acromegaly is an endocrine disorder resulting from excessive growth hormone production and is characterised by insulin resistance despite having reduced liver fat content.…”

Section: Proton Magnetic Resonance Spectroscopy ( 1 H-mrs) Studiesmentioning

confidence: 99%

“…Notably, acromegaly is an endocrine disorder resulting from excessive growth hormone production and is characterised by insulin resistance despite having reduced liver fat content 119 . Accordingly, Fellinger et al 118 reported greater insulin resistance and lower hepatic lipids in people with acromegaly compared to healthy controls and this was accompanied by a lower proportion of unsaturated hepatic lipids. Therefore, these studies provide further human evidence of the dissociation between hepatic steatosis and insulin resistance, and support the notion that elevated saturated hepatic lipids, rather than total hepatic lipids, may be a more important determinant of the metabolic consequences of hepatic lipid accumulation.…”

Section: Hepatic Lipid Composition In Obesity‐related Metabolic Diseasementioning

confidence: 99%

The role of hepatic lipid composition in obesity‐related metabolic disease

Willis

Bawden

Malaikah

et al. 2021

Liver International

View full text Add to dashboard Cite

show abstract

“…As indicated above, GH-mediated lipolysis generates NEFA, which serves as a substrate for mitochondrial β (fatty acid) oxidation and ATP generation. In acromegalic subjects, hepatic lipid content is low and is associated with an increase in hepatic ATP synthesis rate as assessed by 31 P/ 1 H-7-T MR spectroscopy [171]. In addition, aHepGHRkd mice under basal conditions suppress the hepatic expression of carnitine palmitoyltransferase 1A (Cpt1a), independent of changes NEFA levels, or enhanced hepatic insulin signaling [59].…”

Section: Fatty Acid Oxidationmentioning

confidence: 99%

Towards Understanding the Direct and Indirect Actions of Growth Hormone in Controlling Hepatocyte Carbohydrate and Lipid Metabolism

Vázquez‐Borrego

Río-Moreno

Kineman

2021

Cells

View full text Add to dashboard Cite

Growth hormone (GH) is critical for achieving normal structural growth. In addition, GH plays an important role in regulating metabolic function. GH acts through its GH receptor (GHR) to modulate the production and function of insulin-like growth factor 1 (IGF1) and insulin. GH, IGF1, and insulin act on multiple tissues to coordinate metabolic control in a context-specific manner. This review will specifically focus on our current understanding of the direct and indirect actions of GH to control liver (hepatocyte) carbohydrate and lipid metabolism in the context of normal fasting (sleep) and feeding (wake) cycles and in response to prolonged nutrient deprivation and excess. Caveats and challenges related to the model systems used and areas that require further investigation towards a clearer understanding of the role GH plays in metabolic health and disease are discussed.

show abstract

Increased ATP synthesis might counteract hepatic lipid accumulation in acromegaly

Cited by 24 publications

References 48 publications

Metabolite cycled liver ¹H MRS on a 7 T parallel transmit system

Metabolite cycled liver ¹H MRS on a 7 T parallel transmit system

The role of hepatic lipid composition in obesity‐related metabolic disease

Towards Understanding the Direct and Indirect Actions of Growth Hormone in Controlling Hepatocyte Carbohydrate and Lipid Metabolism

Contact Info

Product

Resources

About

Increased ATP synthesis might counteract hepatic lipid accumulation in acromegaly

Cited by 24 publications

References 48 publications

Metabolite cycled liver 1H MRS on a 7 T parallel transmit system

Metabolite cycled liver 1H MRS on a 7 T parallel transmit system

The role of hepatic lipid composition in obesity‐related metabolic disease

Towards Understanding the Direct and Indirect Actions of Growth Hormone in Controlling Hepatocyte Carbohydrate and Lipid Metabolism

Contact Info

Product

Resources

About

Metabolite cycled liver ¹H MRS on a 7 T parallel transmit system

Metabolite cycled liver ¹H MRS on a 7 T parallel transmit system