Liraglutide prevents body and fat mass gain in ovariectomized Wistar rats

Abstract

Estrogens exert beneficial metabolic effects by reducing food intake and enhancing energy expenditure through both central and peripheral mechanisms. The decrease of estrogen, as occurs in ovariectomy (OVX), leads to metabolic disturbances, such as increased body weight, adipose tissue mass, basal blood glucose, and impaired glucose tolerance. These effects can be reversed by reintroducing estrogen. GLP-1 and its receptor agonists, known for their antihyperglycemic properties, also exhibit anorexigenic effects. Besides that, research indicates that GLP-1 analogs can induce metabolic changes peripherally, such as increased fatty acid oxidation and inhibited lipogenesis. Given the shared metabolic actions of GLP-1 and estrogens, we explored whether liraglutide, a GLP-1 agonist, could mitigate the metabolic effects of estrogen deficiency. We tested this hypothesis using ovariectomized rats, a model that simulates menopausal estrogen deficiency, and treated them with either liraglutide or 17β-Estradiol benzoate for 21 days. Ovariectomy resulted in elevated DPP-IV activity in both plasma and inguinal white adipose tissue (iWAT). While estrogen replacement effectively countered the DPP-IV increase in both plasma and iWAT, liraglutide only prevented the rise in iWAT DPP-IV activity. Liraglutide prevented body weight and fat mass gain after ovariectomy to the same extent as estradiol treatment. This can be explained by the lower food intake and food efficiency caused by estradiol and liraglutide. However, liraglutide was associated with increased pro-inflammatory cytokines and inflammatory cells in white adipose tissue. Further research is crucial to fully understand the potential benefits and risks of using GLP-1 receptor agonists in the context of menopause.