Nutrition and Traumatic Brain Injury: Improving Acute and Subacute Health Outcomes in Military Personnel.
Health outcomes associated with choline involve memory, heart disease, and inflammation, which also explain the consideration of choline as a plausible intervention in traumatic brain injury (TBI)…
It is hypothesized that CDP-choline may exert neuroprotective effects in an injured brain through its ability to improve phosphatidylcholine synthesis (Adibhatla and Hatcher, 2002). In addition to its neuroprotective capability, CDP-choline potentiates neurorecovery, which has led to its evaluation as treatment for both stroke and TBI in animal models and in human clinical trials (Cohadon et al., 1982; Levin, 1991; Warach et al., 2000). The positive effects seen in models of ischemia and hypoxia may be explained by increased Bcl-2 expression, decreased apoptosis, and reduced expression of pro-caspase. Inhibiting caspase activity may decrease apoptotic activity and calcium-mediated cell death. Supporting these ideas, in vitro studies have also revealed that choline deficiency induces apoptosis in the liver by mechanisms independent of protein 53, which likely involve abnormal mitochondrial membrane phosphatidylcholine, leakage of oxygen radicals, and activation of caspases (Albright and Zeisel, 1997; Albright et al., 1996, 1998, 1999a, 199b, 2003; Chen et al., 2010). In humans, a choline-deficient diet also causes DNA damage and apoptosis (da Costa et al., 2006).
CDP-choline is generally considered safe; the side effect most noted in clinical trials has been mild diarrhea, with leg edema, back pain with headache, tinnitus, insomnia, vision problems, and dizziness reported much less frequently (Adibhatla and Hatcher, 2002; Clark et al., 1997; Levin, 1991). There were no adverse events reported even with doses as high as 4,000 mg/day (Calatayud Maldonado et al., 1991). It is notable that in a study by Clark and colleagues (2001), a dose of 2,000 mg/day by enteral administration did not induce severe adverse events at a rate any higher than placebo in the 899 patients.
Changes in brain striatum dopamine and acetylcholine receptors induced by chronic CDP-choline treatment of aging mice.
R. Giménez, J. Raïch, and J. Aguilar
1. Spiroperidol binding (dopamine D2 receptors) and quinuclidinyl benzilate binding (muscarinic receptors) in striata of 19-month old mice was analyzed for animals that had received chronic administration of cytidine 5′-diphosphocholine (CDP-choline) incorporated into the chow consumed (100 or 500 mg kg-1 added per day) for the 7 months before they were killed. 2. Treated animals displayed an increase in the dopamine receptor densities of 11% for those receiving 100 mg kg-1 and 18% for those receiving 500 mg kg-1 as compared to the control aged animals that had received no CDP-choline. Control animals showed, from 2 months to 19 months of life, a 28% decrease in the receptor density. No change in the affinity of the receptors for spiroperidol was found in the treated or untreated animals. 3. Muscarinic acetylcholine receptor densities were also partially recovered by the same treatment in aged animals that showed a 14% decrease of these receptors in this case. The muscarinic receptor density increased 6% for the animals that received 100 mg kg-1 and 17% for the animals that received 500 mg kg-1 without any change in the affinity of the receptor for quinuclidinyl benzilate. 4. Aged animals displayed a slight increase in brain membrane fluidity as indicated by a decrease in the polarization value of the non-polar fluorophore 1,6-diphenyl-1,3,5-hexatriene. Interestingly, in the treated animals a greater increase in membrane fluidity was determined and found to be very similar for the two doses.