Amino-Acids: L-Ornithine

L-Ornithine is an intermediate amino-acid in the synthesis of L-arginine and so important in general protein synthesis. It is also important in the synthesis of creatine, a bioactive compound involved in energy transfer in muscles.

L-Ornithine is readily absorbed into the bloodstream.

L-Ornithine Uses

Proteins are composed of amino acids. There are 20 amino acids and the total number and combination determines an almost infinitesimal array of proteins and peptides upon which the body is built and functions with. There are some such as L-ornithine which are not part of the 20 but are needed nonetheless in certain metabolic roles. L-ornithine is critical in the process for removing biological waste material. There is some evidence suggesting this particular amino acid helps raise energy levels along with other health benefits.

The Urea Cycle (a.k.a. Ornithine Cycle)

The Urea Cycle is a critical pathway for dispensing with nitrogen-containing molecules which are the waste materials from protein breakdown. The end product is ammonia which is toxic in the body and so must be removed in the form of urea (incidentally it is as uric acid in birds). The liver turns ammonia into urea which is dissolved in water to form urine. Our kidneys are the organ where this occurs and L-ornithine is at the heart of this process.
Excessive protein breakdown can occur with intense prolonged exercise. Without the presence of ornithine, ammonia can build up as in rare inherited conditions, which leads to toxicity in the blood.

Tiredness And Anti-Fatigue Benefits

The kidneys have other functions to generating urine and cleansing the blood. They convert ornithine to arginine which is a precursor for nitric oxide. This gas is a transmitter for dilating blood vessels so that more blood can reach key tissues. Arginine is also a component in the production of creatine which is a molecule used for energy generation especially in muscles. There is research evidence suggesting that consuming extra ornithine helps promote physical strength and endurance during periods of intense muscle exercise when creatine is required along with ATP (Sugino et al., 2008; Miyake et al., 2014).

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Miyake, M., Kirisako, T., Kokubo, T., Miura, Y., Morishita, K., Okamura, H., & Tsuda, A. (2014). Randomised controlled trial of the effects of L-ornithine on stress markers and sleep quality in healthy workers. Nutrition Journal, 13(1), 53.

Sugino, T., Shirai, T., Kajimoto, Y., & Kajimoto, O. (2008). L-ornithine supplementation attenuates physical fatigue in healthy volunteers by modulating lipid and amino acid metabolism. Nutrition Research, 28(11), pp. 738-743.


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