Intermittent hypoxia affects adipose tissue function in young adults with obesity

<bold>Introduction:</bold> Obesity is linked to obstructive sleep apnea (OSA), characterized by intermittent hypoxia. OSA contributes to metabolic dysfunction, independent of obesity, with adipose tissue dysfunction as a potential mechanism. This study explores how OSA affects the morphology and pathways of adipose tissue in young adults with obesity. <bold>Methods:</bold> Young adults (18–25 years) with obesity referred for bariatric surgery were included. A polysomnography was performed (OSA defined as AHI≥5) and during surgery subcutaneous (SAT) and visceral (VAT) adipose tissue biopsies were taken for H&E-staining and RNA sequencing. <bold>Results:</bold> Twenty-one patients (22.3±0.6 years, 26% male) with obesity (BMI 42.65±1.57 kg/m² and waist 122.2±14.0 cm) were included, of whom 9 were diagnosed with OSA. There were no differences in the mean adipocyte area (VAT: 4082.3±1260.2 µm² vs 3635.5±1035.5 µm²,p=0.4 and SAT: 5559.6±930.1 µm² vs 5660.6±1014.5 µm²,p=0.8) or mean adipocyte diameter (VAT: 67.3±10.2 µm vs 64.0±8.3 µm,p=0.5 and SAT: 78.8±6.6 µm vs 79.8±7.2 µm,p=0.8) between patients with and without OSA. However, sequencing identified 17 (TAP2_5, TMED3, TMEM177, NXPE4, ARHGAP20, TBX5, HLA-DQA1_6, LOC101928004, TAF8, USP32P3, SLC19A3, ABHD5, LOC105374732, APOL4, ZBTB16, LOC105376023 and SMAD7) and 4 (GPI_2, HLA-DQA1_6, CD86 and ZNF718) differentially expressed genes in respectively VAT and SAT, strongly linked to inflammatory and cardiovascular pathways. <bold>Conclusion:</bold> Although no morphological differences were seen, molecular analysis showed altered gene expression in adipose tissue of OSA patients related to inflammation and cardiovascular pathways, suggesting intermittent hypoxia impacts adipose tissue function in obesity.