Inosine is a molecule (known as a nucleoside) that is formed when hypoxanthine is attached to a ribose ring (also known as a ribofuranose) via a β-N9-glycosidic bond. This is an uncommon nucleoside. Inosine is a nucleoside, one of the basic compounds comprising cells. It is a precursor to adenosine, an important energy molecule, and plays many supportive roles in the body.
Based upon anecdotal reports by Russian and Eastern European athletes, inosine has been investigated for exercise-boosting (ergogenic) effects. However, controlled studies have concluded that inosine does not improve athletic performance and may even impair it.
Inosine is a precursor to uric acid, a compound that occurs naturally in the body. Uric acid is believed to block the effect of a toxic free-radical compound (peroxynitrite) that may play a role in the development of multiple sclerosis (MS). In an attempt to raise uric acid levels, ten patients with MS were treated with inosine in amounts up to 3 grams per day for 46 weeks. Three of the ten treated patients showed some evidence of improved function and the others remained stable.4 Controlled studies are needed to confirm these preliminary results.
Inosine is a purine ribonucleoside widely found in plants, animals and other forms of living matter. It is comprised of the purine base hypoxanthine and the sugar D-ribose. Inosine, in the form of its nucleotide, inosine 5'-monophosphate (inosinate), is the precursor of adenosine monophosphate (AMP) and guanosine monophosphate (GMP) in the de novo biosynthesis of purine nucleotides. It is also an intermediate in the so-called salvage pathway of purine nucleotide synthesis, and it is an intermediate in the degradation of purines and purine nucleosides to the purine end-product, uric acid. Inosine is also found as a minor nucleoside in transfer RNA.
Inosine has been found to have potent axon-promoting effects in vivo following unilateral transection of the corticospinal tract of rats. The mechanism of this action is unclear. Possibilities include serving as an agonist of a nerve growth factor-activated protein kinase (N-Kinase), conversion to cyclic nucleotides that enable advancing nerve endings to overcome the inhibitory effects of myelin, stimulation of differentiation in rat sympathetic neurons, augmentation of nerve growth factor-induced neuritogenesis and promotion of the survival of astrocytes, among others.
Inosine is a metabolic activator. It has been used for pre-heavy training by "world class" power-lifters, Soviet and Eastern Block strength athletes to increase oxygen-carrying capacity and promote levels of ATP (Adenosine Tri-Phosphate) a high energy compound that helps muscle contraction. Inosine increases the body's natural ability to handle strenuous exercise, workouts, intense training programs, and competitive events. Inosine belongs to a chemical family called purine nucleotides, the structural units of your body's RNA (ribonucleic acid) and DNA (deoxyribonucleic acid. Inosine boosts the production of ATP thus improving respiration and oxygen transport. For this reason, inosine is used by athletes who wish to exercise longer without experiencing muscle fatigue. Inosine also promotes the production of a substance known as 2,3 DPG which is necessary for the transport of oxygen molecules from the red blood cells to other cells for energy.