FTO intronic SNP strongly influences human neck adipocyte browning determined by tissue and PPARγ specific regulation: a transcriptome analysis

Abstract

<jats:title>Abstract</jats:title><jats:p>Brown adipocytes, abundant in deep-neck (DN) area in humans, are thermogenic with anti-obesity potential. FTO pro-obesity rs1421085 T-to-C SNP shifts differentiation program towards white adipocytes in subcutaneous fat. Human adipose-derived stromal cells were obtained from subcutaneous neck (SC) and DN fat of 9 donors, of which 3-3 carried risk-free (T/T), heterozygous or obesity-risk (C/C) FTO genotypes. They were differentiated to white and brown (long-term PPARγ stimulation) adipocytes, then global RNA sequencing was performed and differentially expressed genes (DEGs) were compared. DN and SC progenitors had similar adipocyte differentiation potential but differed in DEGs. DN adipocytes displayed higher browning features according to ProFAT or BATLAS scores and characteristic DEG patterns revealing associated pathways which were highly expressed (thermogenesis, interferon, cytokine, retinoic acid, with UCP1 and BMP4 as prominent network stabilizers) or downregulated (particularly extracellular matrix remodelling) compared to SC ones. Part of DEGs in either DN or SC browning was PPARγ-dependent. Presence of the FTO obesity-risk allele suppressed the expression of mitochondrial and thermogenesis genes with a striking resemblance between affected pathways and those appearing in ProFAT and BATLAS, underlining the importance of metabolic and mitochondrial pathways in thermogenesis. Among overlapping regulatory influences which determine browning and thermogenic potential of neck adipocytes, FTO genetic background has a so far not recognized prominence.</jats:p>

miR-146a regulates TLR1/2 and 4 induced inflammation and links it with proliferation in human SZ95 sebocytes

“…To obtain global transcriptome data high throughput mRNA sequencing analysis was performed on Illumina sequencing platform as described previously 22,42,43 . Total RNA sample quality was checked on Agilent BioAnalyzer using Eukaryotic Total RNA Nano Kit according to the manufacturer's protocol.…”

Irisin stimulates the release of CXCL1 from differentiating human subcutaneous and deep-neck derived adipocytes via upregulation of NFκB pathway

“…Grouping was performed based on Panther Reactome pathways (https://pantherdb.org). Heatmap visualization was performed on the Morpheus web tool (https://software.broadinstitute.org/morpheus) using Pearson correlation of rows and complete linkage based on calculated z-score of DESeq normalized data after log 2 transformation (29). The interaction networks were determined using STRING (https://string-db.org) and constructed using Gephi 0.9.2 (https://gephi.org).…”

“…The interaction networks were determined using STRING (https://string-db.org) and constructed using Gephi 0.9.2 (https://gephi.org). The size of the nodes was determined based on fold change (29).…”

“…hASCs were isolated and cultivated as previously described ( 27), (29). The absence of mycoplasma was confirmed by PCR analysis (PCR Mycoplasma Test Kit I/C, Promocell, Heidelberg, Germany).…”

“…Cells were collected in Trizol reagent (Thermo Fisher Scientific, MA, USA) and RNA was isolated manually by chloroform extraction and isopropanol precipitation. To obtain global transcriptome data, high throughput mRNA sequencing was performed on Illumina Sequencing platform (29). Grouping was performed based on Panther Reactome pathways (https://pantherdb.org).…”