Cytidine Monophosphate (CMP) and Uridine Monophosphate (UMP): neuronal membrane components. They act similarly enhancing ATP levels and reducing muscle fatigue  which is directly related to neurodegenerative diseases . CMP & UMP contribute in a critical manner to:
1) Formation, regeneration, and growth of the axons and involving myelin .
2) Increase the brain´s cholinergic functions such as the cognitive response.
3) Increase the number of dopamine receptors.
Regarding brain function, UMP and citicoline increase phosphatidylcholine (PC) synthesis, which plays an essential role in brain activity and promoting new neuronal connections. Furthermore, it acts in a synergistic manner with both choline and DHA in the brain . Citicoline is used extensively in cerebral and vascular disorders, conferring neuroprotective, neurostimulator and nootropic properties.
Since UMP is not directly cholinergic, it serves as a fantastic catalyst when combined with alpha-glycerylphosphorylcholine (alpha-GPC) : a precursor of phosphatidylcholine. It is highly bioavailable due to that it crosses the blood-brain barrier and serves as a source of choline, critical for memory and cognitive function. It also provides cellular structural integrity, by promoting synthesis of neuronal membrane components (CMP & UMP).
Phosphatidylserine (PS)  is the main phospholipid found in the inner side of neuronal membranes. PS modulates synaptic receptors, helping to equilibrate neurotransmitter levels.
Inosine has a main neuroprotective role, acting as the urate precursor, a powerful antioxidant that reduces the mitochondrial oxidative stress levels . Therefore, it prevents this energetic source disfunction and the progression of neurodegenerative diseases, also by downregulating the lactate levels .
Finally, Β-Hydroxy-β-Methylbutyrate (HMB)  and Palmitoylethanolamide (PEA) are critical to fight against neuroprotection and neuroinflammation, respectively. HMB not only has been used for the muscle recovery in neurodegeneration-related hospital patients, but also due to its neuroprotective effects, maintaining mitochondrial integrity and reducing oxidative stress. PEA has been incredibly well studied and used in humans for its analgesic-pain management and it ameliorates cognitive impairments. For instance, PEA is the key therapeutical agent to improve cognitive performance in Alzheimer´s Disease (AD) .
In conclusion, the MAIN FUNCTIONS of these actives are:
Neuroprotective & Neuroplasticity Benefits: protects your brain from oxidative stress through these antioxidant effects and improves the capacity to form new neural connections.
Healthy & Young Brain: maintenance of general brain homeostasis and activation of the Nerve Growth Factor (NGF) signaling.
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