January 2001, Volume 25, Issue 1, Pages 95 - 97

Paper

Restoration of fertility in young obese (Lepob Lepob) male mice with low dose recombinant mouse leptin treatment MP Cleary, HM Bergstrom, TL Dodge, SC Getzin, MK Jacobson & FC Phillips The Hormel Institute, University of Minnesota, Austin, Minnesota, USA     Correspondence to: MP Cleary, The Hormel Institute, University of Minnesota, 801 16th Ave NE, Austin, MN 55912, USA. E-mail: mpcleary@smig.net

Keywords

leptin;   obese;   male mice;   fertility;   Lepob Lepob

Abstract

OBJECTIVE: We investigated the effects of low-dose leptin treatment on restoration of fertility in young adult male leptin deficient obese mice. EXPERIMENTAL DESIGN AND RESULTS: MMTV-TGF- Lepob Lepob mice (8-10 weeks old) were treated with recombinant mouse leptin. In experiment 1, four mice (5 µg/g body weight leptin followed by 2.5 µg/g) lost weight and impregnated females (number of pregnancies/number of females, 3/6, 5/6, 5/10, 4/10). In experiment 2, Leptin-Obese (2.5 µg/g) and Control-Lean mice weighed significantly less than Control-Obese mice. Epididymal pad weights of Control-Obese mice were the heaviest, followed by those of Leptin-Obese mice, and Control-Lean mice were the lightest. Testes weight was greater in Control-Lean vs Control-Obese mice. Leptin-Obese mice had testes weight not significantly different from either control group. Four of five Leptin-Obese mice impregnated females (4/10, 5/10, 2/10, 5/12, 0/10). CONCLUSIONS: These results indicate that low-dosage mouse recombinant leptin treatment restored fertility to young Lepob Lepob male mice. Although body weights of Leptin-Obese mice were similar to those of lean age-matched mice, epididymal fat pad weights were heavier. International Journal of Obesity (2001) 25, 95-97

Received 4 February 2000; Revised 4 August 2000; Accepted 20 September 2000

^© Macmillan Publishers Ltd 2001