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CARNOSINE & SUPERJUICES *
Introduction: The Challenge of Deciding what Supplements are Worth Taking. There are many supplements that are recommended to me, promoted to me, and almost forced upon me, hoping that I will be “sold” on them, and so recommend them as essential supplements both for therapy and preventative care. Example: Superjuices – What is the Truth? The so-called ‘super’ fruits goji, noni, açai and mangosteen are rich sources of antioxidants. The marketing message that is common to all superfruits is that they, and their derivative products, are packed full of antioxidants. The promos are worded in such a way as to make one feel guilty if one does not consume them. The following is a typical example:
Most superfruit products are sold in Australia via a multi-level (network) marketing system. You can buy bottles of juice direct from distributors or ‘independent marketing executives’ who earn commissions on sales. Superfruit juices are also sold on-line. You can pay as much as A$85.00 for a litre of one of these juices. In September 2007, ‘Choice’ magazine (published by the Australian Consumers’ Association) published the results of testing the antioxidant activity of nine different superfruit juices. The total antioxidant capacity (TAC) of each of the nine juices was determined by the oxygen radical absorbance capacity (ORAC) assay. The TAC was given for a single serve of each product. This figure was then shown as a percentage of the TAC of a red delicious apple for comparison.
The results of the Choice survey show clearly that eating an apple is far more beneficial than any of the juices tested, from an antioxidant point of view. For the importance of antioxidants, see my January 2007 newsletter ‘Free Radicals - Antioxidants’. Superjuices are cited as an example of the difficulty in deciding what supplements are worthwhile taking, be they for personal use, or recommended at a professional level. CARNOSINE Carnosine is also known as L-Carnosine. Carnosine has been called:
It is said to:
This newsletter will explore the above claims. Carnosine Pharmacology Carnosine is a dipeptide of the two amino acids beta-alanine and histidine (or beta-alanyl-L-histidine). In the body, the enzyme carnosine synthetase forms carnosine from the two amino acids alanine and histidine. Carnosine is found in relatively high concentrations in several body tissues, in particular muscle (both skeletal and heart) and the brain. It is often called a neuropeptide, due to its brain-protective properties. It is also found in the liver and kidneys. It is a 100% natural substance. It acts together with other biological antioxidants (vitamins E, vitamin C, zinc and selenium). It is of interest that the higher the levels of carnosine in meat, the longer is its self-life, as carnosine, being a superb antioxidant, prevents the fat from going rancid. Biological Functions Biological functions of carnosine include:
History of Carnosine as a Medicine and as a Dietary Supplement While carnosine has been known for about a century, its anti-ageing properties have only been extensively studied in recent years. As early as 1935, carnosine was recognised as a treatment for polyarthritis. 1stvitality.co.uk/az/carnosine lists the years, from 1935 onwards, when carnosine was introduced in the treatment of a variety of conditions, including polyarthritis, gastric and duodenal ulcers, hypertension, treatment of trauma, prevention of seizures, anti-inflammatory effects, cataracts, immunological effects and, in 2001, ADHD, epilepsy and other neurological and psychiatric disorders. The biological functions of carnosine explain how, in laboratory studies, it has the ability to protect cells against oxidative stress, as well as to increase their resistance towards functional exhaustion and the accumulation of senile features. Physiological concentrations (20-30 micromols) in standard media prolong the in-vitro (in the test-tube) life-span of human fibroblast cells and strongly reduce the normal features of senescence (ageing). Ageing Protein modification is the major pathway for ageing and degenerative disease. Our body is made up largely of proteins. Because the body’s antioxidant system and other lines of defence cannot completely protect proteins, they undergo destructive changes as we age, largely due to oxidation (as the result of free radical damage) and glycosylation, and another process called carbonylation, where carbonyl groups adhere to the protein molecules. As a result, the proteins break-up, in a process call proteolysis. Antioxidant Properties Carnosine is widely believed to be an antioxidant which stabilizes and protects the cell membrane. It is a water-soluble free-radical scavenger, and prevents lipid peroxidation within the cell membrane. Many antioxidants, like vitamins E and C, prevent free radicals from entering the tissues, but have little or no effect after this first line of defence is broken. Carnosine is not only effective in prevention, but it is also active after free radicals react to form other dangerous compounds like lipid peroxides. So it protects the tissues from these damaging ‘second-wave’ chemicals. Carnosine is a substance that protects and extends the functional life of the body’s key building blocks – cells, protein, DNA and lipids - and can correctly be called the agent of longevity. Glycosylation (Glycation) Most recent research suggests that the most important action of carnosine is its anti-glycosylation effect. What is glycosylation? Simply put, it is the binding of a protein molecule to a glucose molecule, resulting in the formation of damaged, non-functioning structures. Glycosylation alters protein structure and decreases biological activity. Glycosylated proteins, which accumulate in effected tissues, are reliable markers of disease. Many age-related diseases such as arterial stiffening, cataract formation and neurological impairment are at least partly attributable to glycosylation. Glycosylation, also known as the Maillard reaction, occurring between proteins and glucose, is recognised as a major contributor to ageing and possible cancer, as well as the complications arising from diabetes. Glucose provides the fuel for glycosylation, the insidious protein/glucose combination that results (after several steps) in the formation of advanced glycosylation end products (AGEs). Once AGEs are formed, they interact with neighbouring proteins to produce pathological cross-links that ‘toughen’ tissues. Diabetic people form excessive amounts of AGEs earlier in life than non-diabetics. One of the consequences of AGEs is a significant increase in free-radical formation. Specifically, carnosine reacts with and inactivates aldehydes and ketones, reducing protein glycosylation and the formation of AGEs. It also binds to already formed AGEs and inactivates them. Because of its anti-glycosylation actions, carnosine may be useful in preventing and treating diabetic complications such as cataract, neuropathy, arteriosclerosis and kidney failure. Metal Chelation Many investigators believe that carnosine exerts, at least in part, its beneficial health effects as the result of its ability to chelate metals. The term chelate (Greek - to claw), refers to the ability of a material to combine with excess metals in the cells and blood stream, so that the liver and kidneys can excrete them. Chelation therapy is normally given as a series of intravenous infusions of EDTA and various other substances such as penicillamine (at significant expense). This therapy effectively removes heavy metals such as lead, mercury, cadmium, copper, aluminium and nickel. Carnosine, as a dietary supplement, seems to have all the same chelating properties as EDTA. It thus offers an inexpensive oral chelation therapy. Other Benefits Carnosine plays a part in neurotransmission. It protects against cataract formation. Other actions attributed to carnosine, some of which have not as yet been extensively studied, include:
Dosage Carnosine oral supplementation is relatively new and there is no Recommended Daily Allowance (RDA) for it. Early experiments, looking at anti-ageing, used a dose of 50mg daily. At this dose, no side effects were reported. Further studies used 100mg-300mg per day, and there were still no side effects. From present clinical evidence, it would appear that 500mg per day is a correct initial dose (most supplies come in a capsule of 500mg – see sources), increasing, if deemed appropriate as for example when used as chelation therapy, to 1000mg/day. Such dosages have failed to produce any reported serious side effects, toxic effects, or any contra-indications to-date. It is non-toxic. A small number of studies have produced evidence of the beneficial effects of N-acetyl-carnosine eye drops (1%) in the treatment of cataracts. Carnosine can be used together with vitamin E and/or co-enzyme Q10 to give added antioxidant protection, but even if it is used on its own, it should still confer significant protection both against free radicals and against glycosylation. Summary Age-related conditions that carnosine may be useful for include:
Other biological actions include:
Sources of Carnosine The following websites give access to supplies online:
Conclusion Carnosine is well worth considering as a therapeutic supplement.
* Copyright 2008: The Huntly Centre. Disclaimer: All material on the huntlycentre.com.au website is provided for informational or educational purposes only. Consult a health professional regarding the applicability of any opinions or recommendations expressed herein, with respect to your symptoms or medical condition.
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