Zhang J, Ritter RC. Circulating GLP-1 and CCK-8 reduce food intake by capsaicin-insensitive, nonvagal mechanisms. Am J Physiol Regul Integr Comp Physiol 302: R264 -R273, 2012. First published October 26, 2011 doi:10.1152/ajpregu.00114.2011.-Previous reports suggest that glucagon-like peptide (GLP-1), a peptide secreted from the distal small intestine, is an endocrine satiation signal. Nevertheless, there are conflicting reports regarding the site where circulating GLP-1 acts to reduce food intake. To test the hypothesis that vagal afferents are necessary for reduction of food intake by circulating GLP-1, we measured intake of 15% sucrose during intravenous GLP-1 infusion in intact, vagotomized, and capsaicin-treated rats. We also measured sucrose intake during intravenous infusion of cholecystokinin, a peptide known to reduce food intake via abdominal vagal afferents. We found that reduction of intake by GLP-1 was not diminished by capsaicin treatment or vagotomy. In fact, reduction of sucrose intake by our highest GLP-1 dose was enhanced in vagotomized and capsaicin-treated rats. Intravenous GLP-1 induced comparable increases of hindbrain c-Fos immunoreactivity in intact, capsaicin-treated, and vagotomized rats. Plasma concentrations of active GLP-1 in capsaicin-treated rats did not differ from those of controls during the intravenous infusions. Finally, capsaicin treatment was not associated with altered GLP-1R mRNA in the brain, but nodose ganglia GLP-1R mRNA was significantly reduced in capsaicin-treated rats. Although reduction of food intake by intraperitoneal cholecystokinin was abolished in vagotomized and capsaicin-treated rats, reduction of intake by intravenous cholecystokinin was only partially attenuated. These results indicate that vagal or capsaicin-sensitive neurons are not necessary for reduction of food intake by circulating (endocrine) GLP-1, or cholecystokinin. Vagal participation in satiation by these peptides may be limited to paracrine effects exerted near the sites of their secretion.

Objectives: To compare treatment patterns and costs among psoriasis patients with and without metabolic conditions newly initiating a biologic or apremilast. Methods: Adult patients included had !1 prescription for secukinumab, adalimumab, ustekinumab, etanercept, or apremilast between 01/01/2015 and 08/31/2018 (date of first prescription was index date) and no index drug use in the 12-months pre-index, and continuous enrollment in the 12-month pre-index and 24-month post-index periods. Patients were divided into mutually exclusive treatment cohorts and stratified by their pre-index metabolic condition status. Treatment patterns (adherence, non-persistence, switching, discontinuation, use of combination therapy, and re-initiation) and healthcare costs were compared. Results: Overall, 7773 patients were included; 47.5-56.7% had a metabolic condition. Except for the apremilast group, patients with metabolic conditions had higher discontinuation (secukinumab: 50.6% vs. 43.7%; adalimumab à : 53.9% vs. 48.7%; ustekinumab à : 41.9% vs. 35.1%; etanercept: 42.8% vs. 41.2%; apremilast: 43.1% vs. 46.1%) and switching (secukinumab: 48.1% vs. 41.2%; adalimumab à : 47.8% vs. 41.9%; ustekinumab à : 34.5% vs. 25.3%; etanercept à : 53.6% vs. 51.5%; apremilast: 45.8% vs. 44.6%) than patients without (à p < .05). Patients with metabolic conditions incurred significantly higher costs. Conclusion: Many psoriasis patients initiating biologics or apremilast had metabolic conditions. These patients had higher discontinuation and switching, and significantly higher healthcare costs.