Infiltration of intramuscular adipose tissue impairs skeletal muscle contraction

Biltz, Nicole K.; Collins, Kelsey H.; Shen, Karen; Schwartz, Kendall; Harris, Charles; Meyer, Gretchen A.

doi:10.1113/jp279595

Cited by 115 publications

(110 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Skeletal muscle fiber-type was quantified in WT and Skm KO tibialis anterior (TA) muscle as previously described ( Biltz et al, 2020 ). Briefly, sections were immunostained against myosin heavy chain isoforms (type I, type IIa, and type IIb BA‐F8, SC‐71 and BF‐F3, respectively, Developmental Studies Hybridoma Bank, Iowa City, IA) and against laminin (ab11575; Abcam, Cambridge, UK) to quantify fiber types and areas.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

SWELL1 regulates skeletal muscle cell size, intracellular signaling, adiposity and glucose metabolism

Kumar

Xie

et al. 2020

eLife

View full text Add to dashboard Cite

Maintenance of skeletal muscle is beneficial in obesity and Type 2 diabetes. Mechanical stimulation can regulate skeletal muscle differentiation, growth and metabolism, however the molecular mechanosensor remains unknown. Here, we show that SWELL1 (Lrrc8a) functionally encodes a swell-activated anion channel that regulates PI3K-AKT, ERK1/2, mTOR signaling, muscle differentiation, myoblast fusion, cellular oxygen consumption, and glycolysis in skeletal muscle cells. LRRC8A over-expression in Lrrc8a KO myotubes boosts PI3K-AKT-mTOR signaling to supra-normal levels and fully rescues myotube formation. Skeletal muscle targeted Lrrc8a KO mice have smaller myofibers, generate less force ex vivo, and exhibit reduced exercise endurance, associated with increased adiposity under basal conditions, and glucose intolerance and insulin resistance when raised on a high-fat diet, compared to WT mice. These results reveal that the LRRC8 complex regulates insulin-PI3K-AKT-mTOR signalling in skeletal muscle to influence skeletal muscle differentiation in vitro and skeletal myofiber size, muscle function, adiposity and systemic metabolism in vivo.

show abstract

Section: Methodsmentioning

confidence: 99%

“…Skeletal muscle fiber-type was quantified in WT and Skm KO tibialis anterior (TA) muscle as previously described 64 . Briefly, sections were immunostained against myosin heavy chain isoforms (type I, type IIa, and type IIb BA-F8, SC-71 and BF-F3, respectively, Developmental…”

Section: Muscle Fiber Type Quantificationmentioning

confidence: 99%

SWELL1 regulates skeletal muscle cell size, intracellular signaling, adiposity and glucose metabolism

Kumar

Xie

et al. 2020

eLife

View full text Add to dashboard Cite

show abstract

“…The results of the study by Biltz et al . 2020 are the first to show a direct effect of IMAT infiltration in muscle in the absence of injury or disease, eliminating many confounding variables that otherwise would not reveal this causal relationship. However, the underlying mechanism of the ability of IMAT infiltration to impair muscle strength was beyond the scope of the current investigation.…”

Section: Inflammation and Adipose–muscle Crosstalkmentioning

confidence: 99%

Intramuscular adipose tissue: a cause for concern

Hucik

2020

The Journal of Physiology

View full text Add to dashboard Cite

“…Associations between subcutaneous fat thickness and EI estimates of muscle quality in humans are usually discussed from a physiological perspective (Herda et al 2020;Oranchuk et al 2020;Ryan et al 2016;Vakula et al 2019), addressing the damaging effect of obesity on muscle quality that has been confirmed in animal models (Biltz et al 2020;Collins et al 2018). However, the confounding effect that a fat layer may have on EI estimates of muscle quality has not been carefully investigated and is currently not properly taken into account in the literature (Arts et al 2010;Nijboer-Oosterveld et al 2011;Schless et al 2019;Stock et al 2020).…”

Section: Introductionmentioning

confidence: 99%

Examination of the confounding effect of subcutaneous fat on muscle echo intensity utilizing exogenous fat

Müller

Lanferdini

Karam

et al. 2021

Appl. Physiol. Nutr. Metab.

View full text Add to dashboard Cite

We aimed to provide an unbiased estimate of the confounding effect of subcutaneous fat thickness on ultrasound echo intensity (EI) measures of muscle quality. The effect of fat thickness on EI was verified for an approximate range of 0 to 3 cm of fat using exogeneous layers of pork fat over the human tibialis anterior muscle. Sonograms were obtained i) with focus constant across fat thickness conditions and ii) with focus position adjusted to the muscle region of interest (ROI) position for each fat thickness level. In agreement with our hypothesis, increasing fat between the probe and the ROI resulted in a decrease in EI. This overestimating effect of fat on muscle quality differs between sonograms with constant focus and sonograms with focus position adjusted to the vertical displacement in ROI position that occurs for different levels of fat thickness. Correcting equations to account for the overestimating effect of fat on muscle quality are provided for both focus conditions. This is the first study to systematically analyze the confounding effect of fat thickness as an independent factor and the provided equations can be used for improved accuracy in estimates of muscle quality in obese/overweight subjects/patients. NOVELTY • The independent confounding effect of subcutaneous fat thickness on US estimates of muscle quality was quantified • US estimates of muscle quality depend on whether focus is adjusted to the muscle region of interest or not • Equations for correcting muscle quality estimates are provided

show abstract

Infiltration of intramuscular adipose tissue impairs skeletal muscle contraction

Cited by 115 publications

References 57 publications

SWELL1 regulates skeletal muscle cell size, intracellular signaling, adiposity and glucose metabolism

SWELL1 regulates skeletal muscle cell size, intracellular signaling, adiposity and glucose metabolism

Intramuscular adipose tissue: a cause for concern

Examination of the confounding effect of subcutaneous fat on muscle echo intensity utilizing exogenous fat

Contact Info

Product

Resources

About