L-ornithine, the second muscle recovery nutrient
The dynamics of transformations is always fascinating to uphold in nature.
L-arginine, the muscle recovery nutrient we explored in the previous week, can be transformed into another muscle recovery nutrient called L-ornithine. Both of these nutrients are amino acids, which are building blocks of protein molecules. L-ornithine is a product of L-arginine hydrolysis, the breaking down of the L-arginine nutrient upon its reaction with water through the mediation of an enzyme called arginase.
However, L-ornithine, which is an amino acid, can be sourced from animal proteins (meat, fish and eggs). When using these sources, you are actually taking a shortcut in increasing your body’s L-ornithine level without using the L-arginine pathways. L-arginine itself contains 0.11 gram of free L-ornithine per kilogram of L-arginine, according to Norwegian scientists Tone-Kari Ostbye and colleagues in their 2016 article in Aquaculture Nutrition.
In contrast, L-arginine are found in highest levels from plant proteins (soy protein). It can also be found in seeds (nuts, sunflower, sesame etc.), raisins, brown rice, oatmeal and wheat.
Ostbye and colleagues indicated that the role of ornithine in muscle development, and muscle repair and recovery, revolves around its role as a component in the synthesis of proline, a major component in the biosynthesis of protein molecules. Moreover, L-ornithine is necessary in the production and increase of muscle cells (and human cells, in general), collagen formation, among others, according to R. William Caldwell and colleagues in their article in the Physiological Reviews, published in April 2018.
Here are words of caution though. Excessive levels of L-ornithine may cause structure problems in the blood vessels, toxic effects on neurons and abnormal growth of tumor cells. These excess levels, however, are often associated with an overly active arginase enzyme, which converts more L-arginine than the body needs into L-ornithine. Thus, moderation must be observed among those who take L-ornithine supplements. The problem is the toxic level is still unknown. However, the natural presence of 0.11 grams of L-ornithine per kilogram of L-arginine could be a good, but not scientifically tested, guide. Thus, for every 500 grams of L-arginine, the most level of L-ornithine must not go beyond 0.05 grams. However, it is possible that muscle recovery needs may require more.