Therapeutic peptides are chains of amino acids that occur naturally in people, animals, or plants and have been extracted and combined into unique combinations with the goal of treating or curing some kind of disease. Peptides themselves are an important part of human body chemistry, and people generate them naturally. The main idea behind peptide therapy is to help augment these stores and to alter a person’s internal chemistry through natural means so as to enable and strengthen the body to heal itself. Sometimes peptide therapy is used in addition to more standard chemical medications, but it can also be used on its own as an “all natural” treatment. A lot depends on the patient, the doctor, and the disease at issue. Some of the most popular therapies are used to fight cancerous growths and immune conditions, particularly the Human Immunodeficiency Virus (HIV). There are many applications and the field continues to grow and gain acceptance in the wider medical community.
Basic Idea and How They’re Obtained
In almost all cases, peptides used in therapy are pulled directly out of amino acid chains as they occur in nature, though they are sometimes also synthesized using a natural peptide as a template. Naturally occurring peptides are influential mediators in many key biological functions in the body, like blood sugar regulation for example, and their unique status as compounds with low toxicity makes them attractive candidates for treating disease.
Research from many different sources has shown that therapeutic peptide medications have a high specificity for “intended receptors,” which means that they work in many of the same ways that more streamlined pharmaceutical medication does. One of the biggest advantages is that peptides have significantly lower side effect profiles than drugs. High specificity also reduces the chances of dangerous drug-to-drug interactions. Many proponents of therapeutic peptide treatment are working to develop a peptide “library” from which they can mix and match different compounds to create highly specific compounds.
Limitations on Use
As great as these treatments may be, they aren’t usually as flexible as more standard medications, at least not in all settings. For instance, people can’t usually absorb them when taken orally in pill form. Scientifically speaking, this is because peptides have from an extremely low bioavailability against stomach acids. The digestive process breaks up the peptide formulations quickly. This leads to quick degradation and elimination of the peptides before they can become medically active. For this reason, peptides used therapeutically are usually given through injection, though nasal and pulmonary applications are also being developed and tested.
Cancer treatment is one of the most popular applications for this sort of peptide research and therapy. Research has shown that some peptides are able to penetrate cancer cells relatively easily. Certain peptides have also exhibited the ability to inhibit communication between cancer cell colonies and reduce their defenses. In spite of receptive studies being reported, some researchers and doctors still hesitate to use these sorts of peptides in clinical practice. Main reasons for the hesitancy include unique systemic side effects, poor passage through the blood-brain barrier with short plasma half-life, and the limitation of choice in the drug delivery route.
Many of the most effective treatments combine peptides with already-established cancer drugs. Doctors are often able to prevent of the progression of cancer cells by initiating immunotherapy with a recombinant deoxyribonucleic acid (DNA) vaccine coupled with a cocktail of highly specific and selected peptides. Most types of cancerous tumors overexpress this antigen and the therapy has been shown in some limited studies to induce anti-tumor immunity responses. Research is still very much developing in this field.
Immune Response Treatments
Sometimes active peptide groups are also incorporated into medications, as is the case with certain drugs designed to treat HIV-positive individuals. Most of these are purely synthetic peptide groups, which means that they have been created entirely in a lab rather than extracted from nature. Their chemical composition is the same, though.
One example is Tesamorelin, an analog of growth hormone-releasing factor designed by Theratechnologies, a Canadian pharmaceutical corporation. The therapeutic peptide base in Tesamorelin increases the release of growth hormone, which breaks down fatty tissues and can help build up and repair organ tissues that have been subjected to damage caused by the virus, other medications, and other environmental sources.
In Other Clinical Settings
Peptide agents are slowly becoming more prominently used in treatments in a range of clinical settings, though their use does tend to be most popular in holistic cancer centers and other institutes that focus on natural healing. Laboratories and case studies report positive research in combating solid tumors with a cell penetrating elastin-like therapeutic peptide. Stable, synthetically-produced peptides are being researched as new antimicrobial agents, which is welcomed news for many clinical practitioners for whom traditional antibiotics are losing their overall effectiveness. Newer positive outcomes are due, in part, to better routes of administration, which produces more pronounced clinically significant results.