What is Glutamine?
Glutamine is classified as non-essential amino acid because our body is able to synthesize it from other amino acids (arginine, ornithine and proline). However, the demonstration that glutamine concentrations decrease and its metabolism increases during pathological states, catabolic or stressful led to reconsider glutamine as non-essential amino acid and to the alternative hypothesis that can be defined conditionally essential. In these situations, in fact, the body may not be able to cope with the high tissue demands with endogenous synthesis alone, making it necessary to introduce it from external sources.
Glutamine is mainly present in those foods that have appreciable protein levels, primarily of animal origin such as meat, fish, eggs, milk, yogurt and cheese, while among the vegetable sources are beans, spinach, cabbage and beets.
Glutamine performs important and unique functions in the physiology landscape. It is the most abundant free amino acid in plasma and intracellular pools, acts as a precursor for the synthesis of amino acids, proteins, nucleotides and many other biologically important molecules or for the proper development of numerous molecular processes.
Let’s see some of its roles:
It participates in the formation of glutathione, the main antioxidant element at our disposal to counteract excess free radicals and oxidative stress.
At the renal level, it acts as a carrier of amino groups, yielding ammonia, subsequently converted into ammonium NH4+ ion (highly toxic to the body) which is subsequently eliminated in the form of urea.
Acid-base balance regulator
The metabolism of glutamine in the kidneys also involves an important action of buffer of the blood pH, thanks to the formation of bicarbonate, essential to regulate the acid-base balance.
Glutamine is the main nutrient of enterocytes, the cells that make up the intestinal epithelium. Providing trophic support acts as a real repair agent of the mucosa. By now we all know the role of an integral intestinal barrier, on which depends substantially our state of well-being. It is said that most of the diseases originate at the enteric level, if this district is damaged and altered. A precarious intestinal health, in fact, characterized mainly by an altered permeability opens the possibility of exposing the body to harmful substances, which trigger immune reactions sometimes even serious.n the SNC
Glutamine is able to permeate through the blood-brain barrier, reaching the cerebral territories in which it is mainly converted to glutamate, the main excitatory neurotransmitter. However, the toxicity of glutamate should be noted, so that the use of glutamine should also be assessed appropriately. Glutamine is also a precursor of GABA, a neurotransmitter that has inhibitory effects on nerve transmission.
Finally, if our ability to absorb nutrients is lost, all tissues also suffer, not receiving the right nourishment they need to perform their functions at best.
It’s not just enterocytes! It is now widely accepted that glutamine has a high turnover in immune system cells such as lymphocytes, macrophages and neutrophils. It has been reported that glutamine improves many functional parameters of immune cells such as proliferation of T lymphocytes, differentiation of B lymphocytes, phagocytosis of macrophages, antigen presentation and production of cytokines.
We must remember that about 60% The 60% of glutamine present in the human organism is contained in the muscle tissue and its plasma concentrations decrease after an intense and prolonged exercise. But what role does it play at the level of this district?
- Glycogen risintesis: being one of the glucogenetic amino acids is able to undertake metabolic pathways aimed at the formation of glucose when energy reserves are scarce.The process of gluconeogenesis occurs mainly in the liver, which is why glutamine is also useful in the recovery stages from a workout to support the organ to restore its stocks.
• Limitation of proteolysis as a result of myofibril damage induced by exercise, thanks to the ability to "sacrifice" as a carbon and nitrogen donor preserving other amino acids for oxidation for energy purposes.
• Cellular hydration: promoting the entry of water puts the cell in an optimal anabolic state, necessary for uptake and proper use of nutrients.
Why integrate it:
We must remember the main problem regarding this amino acid, represented by the "hunger" of enterocytes, which in fact subtract really important percentages about the quotas assumed, making small the fraction really available. An intelligent supplement requires the consumption of a dose deemed effective (up to 20-30g) to raise blood levels, usually recommended in more times of intake, especially for those critical situations for which endogenous synthesis is inadequate.
Who can benefit from it?
Glutamine is widely used in clinical practice in all those situations where there are particularly marked organ imbalances that compromise its absorption and/or metabolism.
As for the world of fitness, even today there are heated debates about the real usefulness for protein synthesis or pure performance (influenced by factors much more "bulky"), while it is a good choice in athletes to improve recovery, maintain the immune system alert and efficient while reducing susceptibility to infections, typical in the case of exhausting workouts without adequate rest.
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