The increase in body and white adipose tissue weights induced by a high-fat diet were prevented by treatment with the beta3-adrenergic agonist
Trecadrine. Plasma
insulin levels were slightly elevated in
overweight rats, while a decrease was observed in
Trecadrine-treated groups.
Insulin-dependent
glucose uptake was impaired in adipocytes of the
overweight rats in relation to lean animals. The beta3-adrenergic agonist induced an increase in
insulin-stimulated
glucose uptake by adipocytes as compared to the nontreated animals. In fact,
Trecadrine treatment was able to restore to control values the impairment in
insulin-mediated
glucose uptake induced by the cafeteria diet, suggesting that
Trecadrine prevents the development of
insulin resistance in
overweight animals. Basal
leptin secretion was increased in adipocytes of the
overweight rats in relation to lean animals.
Trecadrine treatment induced a decrease in basal
leptin secretion compared to the untreated animals.
Insulin-stimulated
leptin secretion reached similar levels in adipocytes of the
overweight rats as in lean animals. There was a trend for
insulin-induced
leptin secretion to be lower at 24 h in
Trecadrine-treated rats, but it did not reach statistical significance. In conclusion, adipocytes of diet-induced
overweight animals have a higher basal
leptin secretion, which is reduced by treatment with
Trecadrine. However, neither the cafeteria diet nor the
Trecadrine treatment significantly alters the ability of adipocytes to increase
leptin secretion in response to
insulin.