Dapiglutide, a novel dual GLP-1 and GLP-2 receptor agonist, attenuates intestinal insufficiency in a murine model of short bowel.

BACKGROUND: Extensive intestinal resection may lead to short bowel (SB) syndrome, resulting in intestinal insufficiency or intestinal failure (IF). Intestinal insufficiency and IF involve deficiency of the proglucagon-derived hormones glucagon-like peptide-1 (GLP-1) and GLP-2. Two major problems of SB are epithelial surface loss and accelerated transit. Standard treatment now targets intestinal adaptation with a GLP-2 analogue to enlarge absorptive surface area. It is possible that additional benefit can be gained from a combination of GLP-1 and GLP-2 activity, with the aim to enlarge intestinal surface area and slow intestinal transit. METHODS: The GLP-1- and GLP-2-specific effects of the novel dual GLP-1 receptor (GLP-1R) and GLP-2 receptor (GLP-2R) agonist dapiglutide (rINN) were characterized in rodents. Furthermore, in a murine SB model of intestinal insufficiency with 40% ileocecal resection, the influence of dapiglutide on intestinal growth, body weight, food intake, volume status, and stool water content was tested against vehicle and sham-operated male mice. RESULTS: Dapiglutide significantly improves oral glucose tolerance, reduces intestinal transit time, and promotes intestinal growth. In the SB mouse model, dapiglutide promotes body weight recovery, despite unchanged intake of liquid diet. Dapiglutide promotes significant intestinal growth, as indicated by significantly increased villus height as well as intestinal length. Furthermore, dapiglutide reduces stool water losses, resulting in reduced plasma aldosterone. CONCLUSION: Dapiglutide possesses specific and potent GLP-1R and GLP-2R agonist effects in rodents. In the murine SB model, combined unimolecular GLP-1R and GLP-2R stimulation with dapiglutide potently attenuates intestinal insufficiency and potentially also IF.

The long-acting amylin/calcitonin receptor agonist ZP5461 suppresses food intake and body weight in male rats.

The peptide hormone amylin reduces food intake and body weight and is an attractive candidate target for novel pharmacotherapies to treat obesity. However, the short half-life of native amylin and amylin analogs like pramlintide limits these compounds' potential utility in promoting sustained negative energy balance. Here, we evaluate the ability of the novel long-acting amylin/calcitonin receptor agonist ZP5461 to reduce feeding and body weight in rats, and also test the role of calcitonin receptors (CTRs) in the dorsal vagal complex (DVC) of the hindbrain in the energy balance effects of chronic ZP5461 administration. Acute dose-response studies indicate that systemic ZP5461 (0.5-3 nmol/kg) robustly suppresses energy intake and body weight gain in chow- and high-fat diet (HFD)-fed rats. When HFD-fed rats received chronic systemic administration of ZP5461 (1-2 nmol/kg), the compound initially produced reductions in energy intake and weight gain but failed to produce sustained suppression of intake and body weight. Using virally mediated knockdown of DVC CTRs, the ability of chronic systemic ZP5461 to promote early reductions in intake and body weight gain was determined to be mediated in part by activation of DVC CTRs, implicating the DVC as a central site of action for ZP5461. Future studies should address other dosing regimens of ZP5461 to determine whether an alternative dose/frequency of administration would produce more sustained body weight suppression.

Modeling energy intake and body weight effects of a long-acting amylin analogue.

The inhibitory effect of anti-obesity drugs on energy intake (EI) is counter-acted by feedback regulation of the appetite control circuit leading to drug tolerance. This complicates the design and interpretation of EI studies in rodents that are used for anti-obesity drug development. Here, we investigated a synthetic long-acting analogue of the appetite-suppressing peptide hormone amylin (LAMY) in lean and diet-induced obese (DIO) rats. EI and body weight (BW) were measured daily and LAMY concentrations in plasma were assessed using defined time points following subcutaneous administration of the LAMY at different dosing regimens. Overall, 6 pharmacodynamic (PD) studies including a total of 173 rats were considered in this evaluation. Treatment caused a dose-dependent reduction in EI and BW, although multiple dosing indicated the development of tolerance over time. This behavior could be adequately described by a population model including homeostatic feedback of EI and a turnover model describing the relationship between EI and BW. The model was evaluated by testing its ability to predict BW loss in a toxicology study and was utilized to improve the understanding of dosing regimens for obesity therapy. As such, the model proved to be a valuable tool for the design and interpretation of rodent studies used in anti-obesity drug development.

In-vitro and in-vivo studies supporting the therapeutic potential of ZP3022 in diabetes.

GLP-1-gastrin dual agonist ZP3022 has been shown to increase ß-cell mass with a concomitant improvement of glycemic control in diabetic mice and rats. Here we tested the in-vitro effects of ZP3022 on ß-cell proliferation, islet apoptosis and glucose-stimulated insulin secretion (GSIS) in rat islets of Langerhans. Moreover, gene expression profiling in whole pancreas from Zucker Diabetic Fatty (ZDF) rats was performed to characterize genes differently regulated by short-term treatment with ZP3022. Treatments with exendin-4, gastrin-17 alone or in combination were included in the studies. ZP3022 promoted ß-cell proliferation, protected from palmitate-, but not from cytokine-induced apoptosis, and induced an increase in GSIS, demonstrating a glucose dependent insulinotropic action of ZP3022 on ß-cells. The combination treatment with exendin-4 and gastrin-17 showed comparable effects on proliferation, apoptosis, and GSIS as did ZP3022. Microarray analysis revealed that ZP3022 exerted specific effects on pancreatic gene expression not observed when treating ZDF rats with either exendin-4 alone or in combination with gastrin-17. In particular MAPK signaling pathway was observed among the highest affected pathways; while also pathways related to insulin signaling and secretion were regulated by ZP3022. Moreover, rats treated with ZP3022 had a higher expression of genes encoding for the specific ß-cell/endocrine cell markers, such as islet amyloid polypeptide (IAPP), protein convertase 1/3 and -2 (PC 1/3 and-2), as well as transmembrane protein 27(TMEM27) compared to vehicle treated rats. We conclude that ZP3022 may have therapeutic potential in the prevention/delay of ß cell dysfunction.

The anti-diabetic effects of GLP-1-gastrin dual agonist ZP3022 in ZDF rats.

AIMS/HYPOTHESIS: Combination treatment with exendin-4 and gastrin has proven beneficial in treatment of diabetes and preservation of beta cell mass in diabetic mice. Here, we examined the chronic effects of a GLP-1-gastrin dual agonist ZP3022 on glycemic control and beta cell dysfunction in overtly diabetic Zucker Diabetic Fatty (ZDF) rats. METHODS: ZDF rats aged 11 weeks were dosed s.c., b.i.d. for 8 weeks with vehicle, ZP3022, liraglutide, exendin-4, or gastrin-17 with or without exendin-4. Glycemic control was assessed by measurements of HbA1c and blood glucose levels, as well as glucose tolerance during an oral glucose tolerance test (OGTT). Beta cell dynamics were examined by morphometric analyses of beta and alpha cell fractions. RESULTS: ZP3022 improved glycemic control as measured by terminal HbA1c levels (6.2±0.12 (high dose) vs. 7.9±0.07% (vehicle), P<0.001), as did all treatments, except gastrin-17 monotherapy. In contrast, only ZP3022, exendin-4 and combination treatment with exendin-4 and gastrin-17 significantly improved glucose tolerance and increased insulin levels during an OGTT. Moreover, only ZP3022 significantly enhanced the beta cell fraction in ZDF rats, a difference of 41%, when compared to the vehicle group (0.31±0.03 vs. 0.22±0.02%, respectively, P<0.05). CONCLUSION: These data suggest that ZP3022 may have therapeutic potential in the prevention/delay of beta cell dysfunction in type 2 diabetes.