Peptide information and medical benefits by Ray Sahelian, M.D.
Feb 22 2014

 

Peptides are molecules made from the linking of amino acids. Most proteins have a minimum of hundreds of amino acids while peptides range from 2 to about 40 or 50 amino acids although some consider a peptide up to 100 amino acids. A peptide bond forms when the amino group of one amino acid bonds to the carboxyl group of another amino acid.

 

Peptides are categorized into three large classes. These include ribosomal peptides, nonribosomal peptides, and digested peptides.

1. Ribosomal peptides are usually found in higher organisms and function as hormones and signaling molecules.

2. Nonribosomal peptides are confined primarily to unicellular organisms, plants, and fungi.

3. Digested peptides are the result of digestion of proteins in the gastrointestinal system. When certain food proteins such as gluten, casein, and egg protein are broken down, opioid peptides are formed. These peptides are quite short and are given names such as casomorphine, gluten exorphine and dermorphine.

 

Peptides in fermented milk
A traditional Scandinavian beverage, fermented milk, can help reduce blood pressure in people with hypertension. The drink has long been popular in Scandinavian countries and made by adding Lactobacillus to milk, which breaks down the milk protein casein into two types of protein fragments called tripeptides. The tripeptides, isoleucine-proline-proline and valine-proline-proline, have been shown in animal studies to reduce blood pressure and also lower blood pressure in people with mild hypertension. They may work by blocking the blood-pressure-raising chemical angiotensin-converting enzyme (ACE), the same mechanism employed by ACE inhibitor drugs. American Journal of Hypertension, December 2005

 

C Peptide
Connecting peptide (C-peptide) is a product of proinsulin cleavage. C peptide may be involved in the development of long-term complications in type 1 diabetic patients. I am not sure if C12 peptide and C peptide are the same thing.

 

C-peptide for diabetic neuropathy
C peptide is a bioactive peptide and plays a role in the maintenance of microvascular function. C peptide improves sensory nerve function in type 1 diabetic patients with early-stage diabetic neuropathy. Patients with diabetes may be deficient in C peptide. Dr. Karin Ekberg from the Karolinska Institute, Stockholm, Sweden examined whether 6 months of treatment with C peptide improved sensory nerve conduction velocity and other early signs of diabetic neuropathy in the lower extremities of 139 type 1 diabetic patients. They were randomized to low-dose C-peptide at 1.5 mg per day in four divided subcutaneous doses, to a 3-times higher dose, or placebo. After 6 months of treatment, peak sensory nerve conduction velocities improved in the groups treated with low-dose or high-dose C-peptide, but not significantly compared with the control group. However, significantly more patients treated with C-peptide (37%) than patients in the control group (19%) experienced a peak sensory nerve conduction velocity improvement of at least 1 meter/second. Diabetes Care 2007.
   Comments: It is not clear at this time whether C peptide offers an advantage beyond that of alpha lipoic acid.

Brain natriuretic peptide
Beta blockers, angiotensin converting enzyme inhibitors, spironolactone and amiodarone have beneficial effects in decreasing circulating brain natriuretic peptide level during the management of chronic heart failure.

 

Gastrointestinal Peptides
The gastrointestinal tract, besides digesting and processing nutrients, is now regarded as an endocrine organ able to modulate appetite, satiety, and carbohydrate metabolism. Several enteroendocrine cells produce numerous peptides codifying either orexigenic (ghrelin, orexins) or anorexigenic signals (pancreatic polypeptide, peptide YY, cholecystokinin, amylin, bombesin homologs, apolipoprotein A-IV, glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, oxyntomodulin), which interact in a complex network with other peripheral signals of energy balance and with different neuropeptides involved in the central control of appetite and energy homeostasis.

 

Hexarelin
I was a nationally ranked powerlifter. I have toned down my weightlifting due to neck disc damage. What about hexarelin peptides? I read about only benefits, is there any downside?
   The acute administration of hexarelin, a peptidyl GH secretagogue, increases left ventricular ejection fraction in normal subjects and even in patients with severe GH deficiency. Hexarelin, a potent growth hormone (GH)-releasing peptide, is capable of causing profound GH release in normal individuals. It is also a ghrelin analogue.

 

Lunasin peptide

Lunasin is a peptide isolated from soy that has 43 amino acids.

Peptide synthesis

Natriuretic peptide
Natriuretic peptides are naturally occurring substances that act in the body to oppose the activity of the renin-angiotensin system.

 

Neuropeptide Y
People whose genetic make-up produces lower levels of a brain molecule called neuropeptide Y (NPY) may be at increased risk for major depression,

 

Peptide YY
Increased levels peptide YY are elevated in adolescent girls with anorexia. Peptide YY is a hormone released by the gut in response to a recently consumed meal. The more calories the meal contains, the more peptide YY is released. The hormone then travels to the brain where it works to reduce appetite. In rodents as well as in obese adults, peptide YY administration decreases food intake.

Peptides and Appetite
During the past decade, a detailed understanding has emerged of the aminergic and peptidergic neural pathways present within the brain that regulate appetite. Central among the peptide regulators is neuropeptide Y (NPY), a potent orexigenic agent that acts through five different receptor subtypes.
     A neuropeptide essential for wakefulness and appetite also appears to enhance the brain's appetite for cocaine. Drug addiction may be related to the neural circuits that control appetite. In studies with rats, orexin A, a neuro peptide produced in the lateral hypothalamus, strengthens the potential for addiction by enhancing synaptic connections between neurons in the lateral hypothalamus and dopaminergic neurons in the ventral tegmental area (VTA) of the brain. This connection helps provide the "synaptic plasticity" important for full-fledged addiction.

 

Blood pressure, hypertension
Am J Hypertens. 2013. Do the lactotripeptides isoleucine-proline-proline and valine-proline-proline reduce systolic blood pressure in European subjects? A meta-analysis of randomized controlled trials. The peptides IPP and VPP are effective in moderately reducing SBP in European subjects, as is known for Asian populations. These two peptides could therefore have a role in controlling blood pressure (BP), a prospect that merits their further study.

 

Peptides in Food
Most food derived bioactive peptides thus far have been isolated from milk-based products. A wide range of activities has been has been described for bioactive peptides including antimicrobial and antifungal properties, blood pressure-lowering effects, cholesterol-lowering ability, antithrombotic effects, enhancement of mineral absorption, immunomodulatory effects, and localized effects on the gut. Although there is still considerable research to be performed in the area of food-derived bioactive peptides, it is clear that the generation of bioactive peptides from dietary proteins during the normal digestive process is of importance. Therefore, it will become necessary when determining dietary protein quality to consider the potential effects of latent bioactive peptides that are released during digestion of the protein.

 

Peptides. Feb 4 2014. Functional Significance of Bioactive Peptides Derived from Soybean. Biologically active peptides play an important role in metabolic regulation and modulation. Several studies have shown that during gastrointestinal digestion, food processing and microbial proteolysis of various animals and plant proteins, small peptides can be released which possess biofunctional properties. These peptides are to prove potential health-enhancing nutraceutical for food and pharmaceutical applications. The beneficial health effects of bioactive peptides may be several like antihypertensive, antioxidative, antiobesity, immunomodulatory, antidiabetic, hypocholesterolemic and anticancer. Soybeans, one of the most abundant plant sources of dietary protein, contain 36% to 56% of protein. Recent studies showed that soy milk, an aqueous extract of soybean, and its fermented product have great biological properties and are a good source of bioactive peptides. This review focuses on bioactive peptides derived from soybean; we illustrate their production and biofunctional attributes.

 

Crocodile peptide protein
The crocodile species Crocodylus Porusus, apparently one of the largest living crocodiles has a peptide that may have anti virus and bacteria potential. Little research is available on how this peptide destroys germs, and what route of administration is best, the right dosage, whether it really works in humans and if it does for what kinds of infections, and most of all, little is known about the potential danger or risk if used by humans. So much more research needs to be done with this peptide before making any recommendations on its use. There is not guarantee that consumers buying this " crocodile peptide protein " are getting the right molecule and the right amino acids in sequence or whether the bottle even contains anything remote to this substance, and whether there are contaminants present.

 

Q. I am from Sweden but live in Mexico with my 3 year old son. due to the current situation of the pork virus, our relatives here wants us to consume this vaccine called Facinmune, it is the crocodile protein transfer factor, to make our immune system stronger. As i don't now if this is without any risks, i write to you in hope of some answer or/and advice.
   A. I am not familiar with Facinmune vaccine.
 

OHT peptide 3
OHT Peptide-3 contains three peptides: Palmitoyl Pentapeptide-3 (Ceramide Oligopeptide-3), Palmitoyl Tetrapeptide-3, and Acetyl Hexapeptide-3.

 

Peptide Vaccines
Findings from an animal study indicate that inoculation with so-called peptide vaccines can have lethal consequences. A peptide vaccine contains small synthetic proteins designed to activate the immune system against a particular virus or other microbe. In particular, they work by stimulating the body's "killer" T cells to go out and destroy the invading pathogen. Unfortunately, in this study, the T cells appeared to go over-board and killed the animal too. In the study, virus-infected mice that received a peptide vaccine experienced a rapid and severe drop in body temperature. Some of the animals, infected with a virus called LCMV, died within hours of vaccination. The researchers blamed the deaths not on the virus per se, but on the vigorous and overwhelming killer T cell response. Despite these findings, the researchers do not believe that peptide vaccines should be abandoned. Journal of Clinical Investigation, February 2006.

 

Tripeptides - Peptides made of three amino acids
The tripeptide GLF (glycyl-leucyl-phenylalanine) is isolated from human milk proteins. This peptide increases phagocytosis by human and murine macrophages and protected mice against Klebsiella pneumoniae infection. Specific binding sites on human polymorphonuclear leukocytes (PMNs) have been demonstrated.

Q. I would like to know about milk tripeptides. I have been informed that they are very beneficial to lower blood pressure. For example the Evolus milk by Valio. I would like to acquire that product and I know that you are a very respected doctor. I havenít been able to find too much information on milk tripeptides. Could you please point me to the correct product?
   A. I have not studied milk tripeptides in much detail, hence at this time I don't know much about them.

 

Q. Please put something on your website about the active ingredient in Ameal BP which is being advertised on radio and TV as a way to reduce high blood pressure. It has casein derived tripeptides valyl-prolyl-proline and isoleucyl-prolyl-proline.
   A. A search on Medline in 2010 did not reveal any studies with Ameal BP product.  It is unclear from their website what the exact ratios of these tripeptides are, and whether there are additional amino acids or peptides in their formula, and I have not seen independent studies on the accuracy of labeling or purity of the product. Therefore, I do not have much hard data with which to base a reliable opinion on the benefits or side effects of Ameal BP at this time.