ITIH-5 expression in human adipose tissue is increased in obesity.

Abstract

Adipocytes secrete many proteins that regulate metabolic functions. The gene inter-α (globulin) inhibitor H5 (ITIH-5) encodes a secreted protein and is known to be expressed abundantly in the placenta. However, using gene expression profiles data we observed high expression of ITIH-5 in adipose tissue. The aim of this study was to test the hypothesis that ITIH-5 is strongly expressed in human adipocytes and adipose tissue, and is related to obesity and clinical metabolic variables. ITIH-5 adipose tissue mRNA expression was analyzed with DNA microarray and real-time PCR, and its association with clinical variables was examined. ITIH-5 protein expression was analyzed using western blot. ITIH-5 mRNA expression was abundant in human adipose tissue, adipocytes, and placenta, and higher in subcutaneous (sc) compared to omental adipose tissue (P < 0.0001). ITIH-5 mRNA and protein expression in sc adipose tissue were higher in obese compared to lean subjects (P < 0.0001 and P < 0.001, respectively). ITIH-5 mRNA expression was reduced after diet-induced weight loss (P < 0.0001). ITIH-5 mRNA expression was associated with anthropometry and clinical metabolic variables. In conclusion, ITIH-5 is highly expressed in sc adipose tissue, increased in obesity, down regulated after weight loss, and associated with measures of body size and metabolism. Together, this indicates that ITIH-5 merits further investigation as a regulator of human metabolism.

• Authors: Åsa Anveden, Kajsa Sjöholm, Peter Jacobson, Vilborg Palsdottir, Andrew J Walley, Philippe Froguel, Nasser Al-Daghri, Philip G McTernan, Niklas Mejhert, Peter Arner, Lars Sjöström, Lena M S Carlsson, Per-Arne Svensson
• Journal: Obesity (Silver Spring, Md.) (Obesity (Silver Spring)) Vol. 20 Issue 4 Pg. 708-14 (Apr 2012) ISSN: 1930-739X [Electronic] United States
• PMID: 21852814 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• ITIH5 protein, human
• Proteinase Inhibitory Proteins, Secretory
• RNA, Messenger

Topics

• Adipocytes (metabolism)
• Adult
• Blotting, Western
• Body Mass Index
• Cells, Cultured
• Diet, Reducing
• Down-Regulation
• Female
• Humans
• Male
• Middle Aged
• Obesity (genetics, metabolism)
• Oligonucleotide Array Sequence Analysis
• Proteinase Inhibitory Proteins, Secretory (genetics, metabolism)
• RNA, Messenger (metabolism)
• Real-Time Polymerase Chain Reaction
• Subcutaneous Fat (metabolism, pathology)
• Weight Loss