Cholesterol depletion induces transcriptional changes during skeletal muscle differentiation

Abstract

BackgroundMyoblasts undergo major changes in their plasma membrane during the initial steps of skeletal muscle differentiation, including major alterations in the distribution of cholesterol. Cholesterol is involved in crucial membrane functions, such as fluidity, and permeability, and in the organization of specialized membrane microdomains (or lipid rafts). We have previously shown that alterations in cholesterol levels in myoblasts induce changes in proliferation and differentiation, which involves activation of Wnt/beta-catenin signaling pathway. In this study we used methyl-β-cyclodextrin (MbCD) to extract cholesterol from the membrane of chick skeletal muscle cells grown in culture. Using Ion Torrent-based sequencing, we compared the transcriptome of untreated and MbCD treated cells. Our aim was to define the genes that are expressed in these two conditions and relate their expression to cellular functions.ResultsOver 5.7 million sequences were obtained, representing 671.38 Mb of information. mRNA transcriptome profiling of myogenic cells after cholesterol depletion revealed alterations in transcripts involved in the regulation of apoptosis, focal adhesion, phagosome, tight junction, cell cycle, lysosome, adherens junctions, gap junctions, p53 signaling pathway, endocytosis, autophagy and actin cytoskeleton. Lim domain only protein 7 mRNA was found to be the highest up-regulated feature after cholesterol depletion.ConclusionsThis is the first study on the effects of membrane cholesterol depletion in mRNA expression in myogenic cells. Our data shows that alterations in the availability of plasma membrane cholesterol lead to transcriptional changes in myogenic cells. The knowledge of the genes involved in the cellular response to cholesterol depletion could contribute to our understanding of skeletal muscle differentiation.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-544) contains supplementary material, which is available to authorized users.

Cyclodextrins as Emerging Therapeutic Tools in the Treatment of Cholesterol-Associated Vascular and Neurodegenerative Diseases

“…In addition, the authors have reported a decrease in the RCT correlated with the downregulation of ABCA1 and ABCG1. Consequently cholesterol extraction and its resulting depletion from cell membranes may generate a deeper impact in physiology and pathophysiology of cells, body tissue and organ functions as the loss of membrane cholesterol can directly affect the lipid rafts involved in many cell signaling pathways [41][42][43][44]. The other way CD can directly display its biological action consists in the delivery of drug across biological barriers which normally protect the organs against xenobiotics.…”

Knockdown of Lmo7 inhibits chick myogenesis

“…ANOVA with Newman-Keuls post hoc test, *P < 0.001 and ***P < 0.05 compared with control; n = 3. (MbCD) in chick muscle cell cultures [23]. Interestingly, Lmo7 mRNA was found to be the highest up-regulated transcript after cholesterol depletion by MbCD in chick muscle cultures [23].…”

“…(MbCD) in chick muscle cell cultures [23]. Interestingly, Lmo7 mRNA was found to be the highest up-regulated transcript after cholesterol depletion by MbCD in chick muscle cultures [23]. Membrane cholesterol depletion induces the proliferation of myoblasts [22], increases myoblast fusion and leads to the formation of myotubes with increased size [15].…”

“…Furthermore, we showed that the Wnt/beta-catenin pathway is activated by cholesterol depletion [17,22]. Recently, we have shown that cholesterol depletion by MbCD induces transcriptional changes during chick myogenesis [23]. Transcriptome profiling of chick myogenic cells after cholesterol depletion revealed alterations in transcripts involved in the regulation of apoptosis, focal adhesion, phagosome, tight junction, cell cycle, lysosome, adherens junctions, gap junctions, p53 signaling pathway, endocytosis, autophagy and actin cytoskeleton.…”

“…Transcriptome profiling of chick myogenic cells after cholesterol depletion revealed alterations in transcripts involved in the regulation of apoptosis, focal adhesion, phagosome, tight junction, cell cycle, lysosome, adherens junctions, gap junctions, p53 signaling pathway, endocytosis, autophagy and actin cytoskeleton. Interestingly, the highest up-regulated mRNA observed after cholesterol depletion in chick muscle cells was Lim domain only 7 (Lmo7, [23].…”