Aim: The aim of this study was to estimate the lipolytic activity of the human growth hormone variant, 20-kD human growth hormone (20K-hGH). Methods: Obese KV-Ay mice were given daily subcutaneous injections of 20K-hGH (0.25, 0.5, 1.0 mg/kg), 22K-hGH (0.25 mg/kg) or saline as a control for 2 weeks. Body composition (fat, water and protein), lipolysis and lipoprotein lipase (LPL) activity were measured 24 h after the final injection. Results: Both growth hormone isoforms significantly reduced relative fat pad and whole body lipids. In addition, 20K-hGH produced an inhibition of LPL activity in adipose tissue and stimulated lipolysis in adipocytes. Conclusion: These data strongly suggest that inhibition of LPL activity in adipose tissue and stimulation of lipolysis in adipocytes by 20K-hGH treatment reduce adipose tissue mass, resulting in body fat reduction.

Keywords:
Human growth hormone, 20 kD, Human growth hormone, 22 kD, Obese KK-Ay mice, Lipolysis, Lipoprotein lipase activity
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2002
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