UK peptides are short strings of amino acids that create proteins in the body (under the right conditions). Peptides have numerous benefits, from muscle building to reducing inflammation, and they’re also effective at treating joint pain. However, it’s important to be aware of the risks that come with peptides, and only take them under the supervision of a doctor or pharmacist.
One area where peptides can be beneficial is in the gut, where they have been shown to stimulate the growth of good bacteria and reduce digestive problems. They can also help with weight loss and regulating blood sugar levels. In fact, the glucagon-like peptide 1 (GLP-1) drug semaglutide is an exciting new treatment for type 2 diabetes and obesity. This medication is a synthetic version of the natural hormone GLP-1, which promotes insulin secretion and slows down glucose production.
Despite this, the research on gut-derived bioactive peptides is still in its infancy and it’s important to understand the underlying mechanisms of their effects. This is particularly true for the more complex peptides such as those containing opioid agonist activity. In addition to the obvious effects of promoting appetite, lowering blood pressure and suppressing intestinal motility, peptides containing opioid activity can also activate a number of different receptors including the m-receptor that affects emotional behaviour, the d-receptor that controls pain sensation and the k-receptor that regulates satiety signals and thus food intake.
Another issue in this area of peptide research is that it’s often difficult to demonstrate measurable health benefits arising from dietary bioactive peptides. This is because the bioactive peptide must first be absorbed, and then the concentrations that reach the target cells or receptors must be sufficiently high to produce an effect.
This is a particular challenge in the case of the GLP-like peptides, where only very small amounts of the peptide are absorbed into the gut. Studies involving the fermented milk product Calpis(tm), which contains the GLP-like tripeptides VPP and IPP, have shown that these can lower blood pressure when consumed in animal models, but it’s not clear whether this is due to paracellular diffusion or direct action on the gut cells.
The final article in this special issue comes from Professor Marc Vendrell at the University of Edinburgh, who provides a comprehensive review of the recently developed class of bi-functional cell penetrating peptides known as bioportides. These peptides can act as regulators of protein-protein interactions and he gives an excellent overview of the methods available for designing such molecules. He also covers lessons that can be learned from the crystal structures of stapled peptides bound to their target proteins and describes some of the recent advances in the field.