Paper
International Journal of Obesity (2003) 27, 457–462. doi:10.1038/sj.ijo.0802252
Leptin does not respond to 48 h fat deposition or mobilization in women
P R Murgatroyd1, G Frühbeck1, G R Goldberg1, S A Jebb2, F E Leahy1, M S Moore1 and A M Prentice1
- 1MRC Dunn Clinical Nutrition Centre, Cambridge, UK
- 2MRC Human Nutrition Research, Cambridge, UK
Correspondence: PR Murgatroyd, Wellcome Trust Clinical Research Facility, Box 127, Addenbrookes Hospital, Hills Road, Cambridge CB2 2QQ, UK. E-mail: prm13@cam.ac.uk
Abstract
OBJECTIVE: To test the hypothesis that acute responses of plasma leptin concentration to energy balance manipulation are mediated by fat flux.
DESIGN: Ten healthy women aged 31–63 y, mass 48–113.5 kg, fat mass 8.5–62.5 kg, were studied for 3 days in a whole-body calorimeter on two occasions. After a control day (D1) during which energy balance was maintained, diet was manipulated to induce fat deposition (FD) or mobilization (FM) of 50 g/day for 2 days (D2 & D3). A difference totalling of 194
18.6 g fat was achieved between manipulations without significant effects on carbohydrate or protein balance. Fasting plasma leptin was measured on D2 and D4.
RESULTS: After the control day plasma leptin concentration averaged 19.019.8 ng/ml, and was found to be linearly related to body fat mass. After 2 days manipulation of fat balance, leptin concentrations were 21.410.3 ng/ml (FD) and 21.211.3 ng/ml (FM). There was no significant difference between treatments in either control day or postmanipulation leptin concentrations, nor did the treatments induce any differences in glucose or insulin concentration responses.
CONCLUSION: Although in states of energy balance leptin concentration is linearly related to fat mass, acute modulation of leptin concentration during energy imbalance is not mediated by fat flux.
Keywords:
leptin, fat intake, fat mass, calorimetry, energy balance
