Calorie-restriction reverses leptin resistance in middle-aged rats.

Middle-aged C57BL/6 mice have impaired responses to leptin that are not improved by calorie restriction.

Midlife weight gain occurs in many species, suggesting that leptin signaling is impaired at middle age. To test this hypothesis, we measured changes in food intake and body composition in young (Y) and middle-aged (MA) C57BL/6 male mice infused subcutaneously with phosphate-buffered saline or leptin. Leptin-induced decreases in food intake and body fat were delayed in MA mice and associated wit...

The Effect of Peripheral Injection of Leptin on Biomarkers of Aging in Calorie Restricted Rats

Background and Objectives: Calorie restriction (CR) is one of the proven methods of extending lifespan and slowing aging. Leptin is a nutritionally regulated adipokine that has been proposed as a possible key signal in the adaptive responses relevant to CR. Under CR, plasma leptin levels decrease, thus it was hypothesized that leptin administration may counteract CR-induced weight loss. Therefo...

Impaired leptin responsiveness in aged rats.

We previously reported that adiposity and serum leptin levels increase with age in male F-344xBN rats and that when physiological levels of serum leptin are manipulated by fasting, there is a corresponding reciprocal change in hypothalamic neuropeptide Y (NPY) mRNA in young rats, but there are no changes in older rats. These findings suggest that the regulation of hypothalamic NPY mRNA by lepti...

Calorie Restriction Attenuates Monocrotaline-induced Pulmonary Arterial Hypertension in Rats

Calorie restriction (CR) is one of the most effective nonpharmacological interventions protecting against cardiovascular disease, such as hypertension in the systemic circulation. However, whether CR could attenuate pulmonary arterial hypertension (PAH) is largely unknown. The PAH model was developed by subjecting the rats to a single subcutaneous injection of monocrotaline. CR lowered mean pul...

Calorie Restriction, Longevity and Cognitive Function