Where to Buy Peptides in Australia

Because of their shorter half-life, few peptides accumulate in tissues and thereby reduce the dangers that arise from complications from their breakdown products. Compared to the larger proteins and antibodies, peptides can penetrate deeper into the tissue. In addition, they are generally less immunogenic than recombinant proteins and antibodies. In addition, there are lower production costs, higher activity, greater stability (storage at room temperature). Many therapeutic peptides are derived from natural proteins or polypeptides and in many cases interact with membrane proteins. Small amounts are usually sufficient to activate or deactivate the target receptors. Few peptide antagonists that inhibit the ligand-receptor interaction have so far reached the market. The general rule,

Many of the peptide products on the market are peptide hormones or peptide derivatives that stimulate hormone action. The admission rate has been increasing since 2000. The high point for the time being was 2012, when six peptide active ingredients came onto the market in the USA and five in the EU. However, one in the USA was withdrawn in 2013. A GLP-1R agonist (lixisenatide) was approved for the treatment of type 2 diabetes in 2013, while a synthetic peptide hormone (afamelanotide) for skin cancer prophylaxis is still being examined by the EMA until mid-2014. As early as 2006, a recombinant human parathyroid hormone (Preotact) came onto the market for the prevention of vertebral fractures in postmenopausal women.

There are around a dozen peptide molecules in late clinical phases. The approved peptide active ingredients cover a wide range of indications and are administered intravenously, subcutaneously, inhalatively and even orally (linaclotide). The majority of the approximately 120 test substances target the indications oncology and infection. More than half of the pipeline peptides have a single target structure in their sights, one tenth target microbes. The target structures most frequently targeted are the membrane proteins, which are located in the outer cell membrane and conduct external stimuli into the interior of the cell, especially G-protein-coupled receptors (almost 40 percent, according to Kaspar / Reichert). Many of the peptides that are currently in phase II have been linked to other molecules such as PEG or lipids.

We can use it to synthesize peptides that nature cannot produce and that have improved properties, “says the chemist from Ulm. One inevitably thinks of Lego building blocks when Tanja Weil explains why peptides are now so well suited for ‘pharmaceutical development’ Take cysteine, for example. This sulfur-containing, naturally occurring amino acid can form disulfide bridges that stabilize the molecule. Cysteine, if incorporated in a specific location, could also link peptides to one another. With this, according to Weil, coupling reactions could be optimized in such a way that in the end a functional protein could even be produced in the test tube. The complete production of an enzyme in a test tube is still a dream. But the way there seems to be mapped out.

In Weil’s assessment, some optimization strategies have now reached a certain degree of maturity. In the meantime, tests are being carried out on animals with encapsulated peptide active ingredients that are supposed to pass through the gastrointestinal tract. The bioavailability of peptides can be extended by transporting them with the help of nano-vehicles such as mesoporous silica particles or by attaching polymers such as polyethylene glycol groups to the active peptide compounds (PEGylation). These polymers are known for their low adsorption on plasma proteins, which keeps the active ingredients stable in the bloodstream for longer and allows them to reach cellular surface receptors.

Research also expects a stabilizing effect from adding groups to the biomolecules that are not recognized by enzymes as quickly. The breakdown of peptide active ingredients by digestive enzymes can be slowed down, for example, by incorporating D-amino acids instead of L-amino acids. Recently, the Münch, Kirchhoff and Weil working groups identified and characterized a peptide that forms visible aggregates that significantly improve the transport of viruses into cells and could be of interest for gene therapy, for example. “There are some promising approaches here”, not least in Ulm, where research is more advanced than with oral availability, says Tanja Weil.

Biologicals such as peptides are gaining in importance thanks to their high specificity and biological activity, as many small molecules fail due to toxic metabolites and unintended interactions. In view of advanced optimization strategies, peptide active ingredients are now regarded as an attractive class of substances that can open up new indications in the semi-synthetic area, including in the CNS area (Vlieghe, 54). Peptides are already being tested as anti-cancer and anti-inflammatory agents, as antibiotics and enzyme inhibitors in a large number of indications. A great future is predicted for antimicrobial peptides.

The search for active ingredients in nature is not a new idea, the search in human body fluids is new. That could be an advantage, because “the problem is always the separation, even with small molecules, their isolation and purification,” says Weil. The body’s own peptides logically have a different toxicological profile than exogenous substances extracted from sponges or cytotoxic substances from tree bark.

And it is not only researchers from Ulm who believe that the degradome, the sum of the proteins broken down by proteolytic enzymes, is not biological waste and not a coincidence. The importance of this degradome is supported by the observation that the more than 500 proteases that cut these peptides from proteins can be altered under pathological conditions. In addition, there is increasing evidence that some of these cleavage products of larger proteins show specific and sometimes highly unexpected activity against human pathogens.

It is very likely that many important peptide immune modulators and effectors are hidden in the human organism. A dozen therapeutically interesting peptides with antimicrobial and anti- or proviral activity that were fished from human peptide libraries are already known (Münch, Ständker, 15). Not every peptide obtained from body fluids is suitable for development as a therapeutic agent. The Ulm team also rate the gain in knowledge as a gain. Because their hope is to increase the understanding of the control of and entry into cells and possibly discover completely new active or defense mechanisms of the body.