Other peptides degraded by DPP-4 and their actions, stimulated during DPP-4 inhibition
| Peptide | Actions |
|---|---|
| PYY (1–36) | Gastric acid secretion ↓ Gastric emptying ↓ GI transit ↓ Electrolyte/water secretion↓ Pancreatic exocrine secretion ↓ Gallbladder contraction ↓ |
| NPY (1–36) | GI motility ↓ Electrolyte/water secretion ↓ Intestinal inflammation ↑ |
| GLP-2 (1–33) | Gastric acid secretion ↓ Intestinal mucosa growth ↑ Nutrient absorption ↑ Intestinal blood flow ↑ GI transit ↓ |
| GIP (1–42) | Intestinal glucose uptake ↑ GI transit ↓ |
| VIP | Gastric acid secretion ↓ Electrolyte/water secretion ↓ Nutrient absorption ↓ Bicarbonate secretion ↑ GI transit ↑ Gallbladder contraction ↓ |
| Bradykinin | Nociception/pain ↑ Hepatic gluconeogenesis ↓ Gallbladder contraction ↑ |
| SP | GI transit ↑ Intestinal chloride secretion ↑ Intestinal inflammation ↑ |
| Prolactin | Gastric emptying ↓(♂) /↑ (♀) |
| Endomorphin-2 | GI transit ↓ |
| GRP | Gastrin release ↑ |
| Interleukin 2 | Intestinal chloride secretion ↑ |
| CLIP | Amylase release ↑ |
In addition to GLP-1, DPP-4 cleaves a number of other peptides and hormones. Therefore, inhibition of DPP-4 also leads to altered levels and activity of these substrates. Whether these effects, which were mainly demonstrated in preclinical models, have a role in patients remains to be demonstrated.
CLIP, corticotropin-like intermediate lobe peptide; GIP, glucose-dependent insulinotropic peptide; GLP-2, glucagon-like peptide 2; GRP, gastrin-releasing peptide; NPY, neuropeptide Y; PYY, peptide YY; SP, substance P; VIP, vasoactive intestinal peptide.