Protective and Curative Antiobesity Potential of Lemon Peel Extract in Rats Fed on High Fat Diet: Mechanism of Action

Aim: This study was to investigate the effect of dietary lemon peel extract (LPE) on high fat diet induced obesity in rats. Some of the LPE mechanism of action was also elucidated. Fifty adult rats were divided into five groups: 1) normal control, 2) lemon peel extract group supplemented with 0.5 g% LPE for 12 weeks, 3) high fat diet-fed (HFD) for 12 weeks, 4) preventive group fed on high fat diet supplemented with LPE 0.5 g% for 12 weeks and 5) therapeutic group fed on high fat diet for 12 weeks then supplemented with LPE 0.5 g% further 6 weeks.

Methodology: Body weight gain, feed efficiency ratio, serum lipid profile, serum glucose, serum insulin, erythrocytes glucose-6-phosphate dehydrogenase (G6PD) activity, serum adiponectin, leptin, acyl coenzyme A oxidase (ACO) and medium chain acyl coenzyme A dehydrogenase (MCAD) activities were measured.

Results: Body weight gain, lipid profile, glucose, insulin, G6PD activity and leptin were significantly suppressed by the effect of LPE in treated groups. LPE also, up-regulated ACO and MCAD activities in the LPE-treated groups. Additionally mRNA level of ACO in the liver was up-regulated in LPE-treated groups compared with HFD.

Conclusion: These findings demonstrate that LPE prevent body weight gain and fat accumulation through improvement of lipid metabolism by up-regulating the activities of MCAD and ACO while down regulating the activity of glucose 6 phosphate dehydrogenase. In this context, the preventive effect of LPE was more pronounced than the therapeutic effect.