Physiological and metabolic differences between visceral and subcutaneous adipose tissues in Nile tilapia (Oreochromis niloticus).
Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SCAT) have different structures and metabolic functions and play different roles in the regulation of the mammal endocrine system. However, little is known about morphology and physiological and metabolic functions between VAT and SCAT in fish. We compared the morphological, physiological, and biochemical characteristics of VAT and SCAT in Nile tilapia and measured their functions in energy intake flux, lipolytic ability, and gene expression patterns. SCAT contained more large adipocytes and nonadipocytes than VAT in Nile tilapia. VAT had higher lipid content and was the primary site for lipid deposition. Conversely, SCAT had higher hormone-induced lipolytic activity. Furthermore, SCAT had a higher percentage of monounsaturated and lower polyunsaturated fatty acids than VAT. SCAT had higher mitochondrial DNA, gene expression for fatty acid β-oxidation, adipogenesis, and brown adipose tissue characteristics, but it also had a lower gene expression for inflammation and adipocyte differentiation than VAT. SCAT and VAT have different morphological structures, as well as physiological and metabolic functions in fish. VAT is the preferable lipid deposition tissue, whereas SCAT exhibits higher lipid catabolic activity than VAT. The physiological functions of SCAT in fish are commonly overlooked. The present study indicates that SCAT has specific metabolic characteristics that differ from VAT. The differences between VAT and SCAT should be considered in future metabolism studies using fish as models, either in biomedical or aquaculture studies.
['Wang|Ya-Wen|YW|', 'Zhang|Ji-Lei|JL|', 'Jiao|Jian-Gang|JG|', 'Du|Xiao-Xia|XX|', 'Limbu|Samwel Mchele|SM|', 'Qiao|Fang|F|', 'Zhang|Mei-Ling|ML|', 'Li|Dong-Liang|DL|', 'Du|Zhen-Yu|ZY|']
D017667:Adipocytes D000818:Animals D023681:Cichlids D018752:Diet, Fat-Restricted D059305:Diet, High-Fat D004041:Dietary Fats D004734:Energy Metabolism D005215:Fasting D005227:Fatty Acids D029941:Fish Proteins D005786:Gene Expression Regulation D018836:Inflammation Mediators D050152:Intra-Abdominal Fat D050155:Lipogenesis D008066:Lipolysis D008297:Male D009928:Organ Specificity D012333:RNA, Messenger D050151:Subcutaneous Fat D013997:Time Factors D014284:Triiodothyronine
metabolism subcutaneous adipose tissue Nile tilapia visceral adipose tissue gene expression pattern