Cardiovascular effects of CDP-choline and its metabolites: involvement of peripheral autonomic nervous system

Novel Energy Drink Improves Cognitive Function and Mood, without Influencing Myocardial Oxygen Demand or Ventricular Repolarization in Adult Gamers: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial

OBJECTIVES

To examine the efficacy of acute consumption of a novel energy drink (C4S) versus placebo for improving cognitive and gaming performance and mood. Secondarily, we examined the cardiovascular safety profile of acute C4S consumption.

METHODS

Forty-five healthy, young adult video gamers completed two experimental visits in randomized order where they consumed either C4S or a placebo and then completed a validated battery of neurocognitive tests, played five video games, and completed a mood state survey. Blood pressure (BP), heart rate (HR), oxygen saturation, and electrocardiogram measurements were taken at baseline and repeated throughout each visit.

RESULTS

Acute consumption of C4S improved cognitive flexibility (absolute mean or median difference [95% CI] = +4.3 [2.2-6.4]; p < 0.001; d = 0.63), executive function (+4.3 [2.3-6.3]; p < 0.001; d = 0.63), sustained attention (+2.1 [0.6-3.6]; p = 0.01; d = 0.44), motor speed (+2.9 [0.8-4.9]; p < 0.001; d = 0.44), psychomotor speed (+3.9 [0.1-7.7]; p = 0.04; d = 0.32) working memory (+1.0 [0.1-1.9]; p = 0.02; d = 0.35), and performance in the two-dimensional visuospatial game Tetris (+463 [-419-2,065] pts; p = 0.049; d = 0.30) compared to placebo. C4S also improved Fatigue-Inertia (-1 [-3-0]; p = 0.004; d = 0.45), Vigor-Activity (+2.4 [1.3-3.6]; p < 0.001; d = 0.64), Friendliness (+0 [0-1]; p = 0.04; d = 0.32), and Total Mood Disturbance (-3 [-6-0]; p = 0.002; d = 0.44). BP increased slightly in C4S versus placebo, while HR decreased from baseline to post-drink in the C4S condition. Rate-pressure-product was higher in C4S versus placebo independent of time but did not increase from baseline. There was no effect on corrected QT interval.

CONCLUSION

Acute consumption of C4S was efficacious for cognitive performance, visuospatial gaming performance, and mood enhancement, and had no effect on myocardial oxygen demand or ventricular repolarization, despite being associated with increases in BP.

Preventive effects of antenatal CDP-choline in a rat model of neonatal hyperoxia-induced lung injury

Antenatal steroid administration to pregnant women at risk of prematurity provides pulmonary maturation in infants, while it has limited effects on incidence of bronchopulmonary dysplasia (BPD), the clinical expression of hyperoxia-induced lung injury (HILI). Cytidine-5'-diphosphate choline (CDP-choline) was shown to alleviate HILI when administered to newborn rats. Therefore, we investigated effects of maternal administration of CDP-choline, alone or in combination with betamethasone, on lung maturation in neonatal rats subjected to HILI immediately after birth. Pregnant rats were randomly assigned to one of the four treatments: saline (1 mL/kg), CDP-choline (300 mg/kg), betamethasone (0.4 mg/kg), or CDP-choline plus betamethasone (combination therapy). From postnatal day 1 to 11, pups born to mothers in the same treatment group were pooled and randomly assigned to either normoxia or hyperoxia group. Biochemical an d histopathological effects of CDP-choline on neonatal lung tissue were evaluated. Antenatal CDP-choline treatment increased levels of phosphatidylcholine and total lung phospholipids, decreased apoptosis, and improved alveolarization. The outcomes were further improved with combination therapy compared to the administration of CDP-choline or betamethasone alone. These results demonstrate that antenatal CDP-choline treatment provides benefit in experimental HILI either alone or more intensively when administered along with a steroid, suggesting a possible utility for CDP-choline against BPD.

Integrated proteomic and metabolomic profile analyses of cardiac valves revealed molecular mechanisms and targets in calcific aortic valve disease

Background

This study aimed to define changes in the metabolic and protein profiles of patients with calcific aortic valve disease (CAVD).

Methods and results

We analyzed cardiac valve samples of patients with and without (control) CAVD (n = 24 per group) using untargeted metabolomics and tandem mass tag-based quantitative proteomics. Significantly different metabolites and proteins between the CAVD and control groups were screened; then, functional enrichment was analyzed. We analyzed co-expressed differential metabolites and proteins, and constructed a metabolite-protein-pathway network. The expression of key proteins was validated using western blotting. Differential analysis identified 229 metabolites in CAVD among which, 2-aminophenol, hydroxykynurenine, erythritol, carnosine, and choline were the top five. Proteomic analysis identified 549 differentially expressed proteins in CAVD, most of which were localized in the nuclear, cytoplasmic, extracellular, and plasma membranes. Levels of selenium binding protein 1 (SELENBP1) positively correlated with multiple metabolites. Adenosine triphosphate-binding cassette transporters, starch and sucrose metabolism, hypoxia-inducible factor 1 (HIF-1) signaling, and purine metabolism were key pathways in the network. Ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), calcium²⁺/calmodulin-dependent protein kinase II delta (CAMK2D), and ATP binding cassette subfamily a member 8 (ABCA8) were identified as hub proteins in the metabolite-protein-pathway network as they interacted with ADP, glucose 6-phosphate, choline, and other proteins. Western blotting confirmed that ENPP1 was upregulated, whereas ABCA8 and CAMK2D were downregulated in CAVD samples.

Conclusion

The metabolic and protein profiles of cardiac valves from patients with CAVD significantly changed. The present findings provide a holistic view of the molecular mechanisms underlying CAVD that may lead to the development of novel diagnostic biomarkers and therapeutic targets to treat CAVD.

Choline or CDP-choline restores hypotension and improves myocardial and respiratory functions in dogs with experimentally - Induced endotoxic shock

Endotoxin shock is associated with severe impairments in cardiovascular and respiratory functions. We showed previously that choline or cytidine-5'-diphosphocholine (CDP-choline) provides beneficial effects in experimental endotoxin shock in dogs. The objective of the present study was to determine the effects of choline or CDP-choline on endotoxin-induced cardiovascular and respiratory dysfunctions. Dogs were treated intravenously (i.v.) with saline or endotoxin (LPS, 0.1 mg/kg) 5 min before i.v. infusion of saline, choline (20 mg/kg) or CDP-choline (70 mg/kg). Blood pressure, cardiac rate, myocardial and left ventricular functions, respiratory rate, blood gases, serum electrolytes and cardiac injury markers were determined before and at 0.5-48 h after endotoxin. Plasma tumor necrosis factor alpha (TNF-α), high mobility group box-1 (HMGB1), catecholamine and nitric oxide (NO) levels were measured 2 h and 24 h after the treatments. Endotoxin caused immediate and sustained reductions in blood pressure, cardiac output, pO₂ and pH; changes in left ventricular functions, structure and volume parameters; and elevations in heart rate, respiratory rate, pCO2 and serum electrolytes (Na, K, Cl, Ca and P). Endotoxin also resulted in elevations in blood levels of cardiac injury markers, TNF-α, HMGB1, catecholamine and NO. In choline- or CDP-choline-treated dogs, all endotoxin effects were much smaller in magnitude and shorter in duration than observed values in controls. These data show that treatment with choline or CDP-choline improves functions of cardiovascular and respiratory systems in experimental endotoxemia and suggest that they may be useful in treatment of endotoxin shock in clinical setting.

Chemotranscriptome analysis indicates the neurotrophic and neuromodulator effects of a citicoline molecule

Objective: to investigate the effect of citicoline (CTC) on gene transcription.

Material and methods. Chemotranscriptome analysis of the CTC molecule was carried out on an NPC.TAK model, provided that the cells were incubated with CTC for 24 hours.

Results and discussion. CTC dose-dependently affected the transcription of 8,838 out of 12,716 annotated human genes, mainly by increasing the transcription of the genes involved: 1) in the neurotransmitter metabolism of serotonin (n=36), dopamine (n=32), GABA (n=14), and acetylcholine (n=27); 2) in showing the effects of neurotrophic factors (n=152), including nerve growth factor (n=11); 3) in maintaining the cardiovascular system (vasodilation and cardiac electrical activity; a total of 76 genes). CTC reduced the transcription of the genes, whose protein activity supported inflammation (n=86) and cell division (n=656). CTC elevated the expression of 60 genes involved in triglyceride processing and decreased the expression of 51 genes whose proteins were involved in cholesterol metabolism. CTC increased the transcription of the genes involved in the body’s response to various drugs, including antiepileptic drugs (n=20), dopaminergic agents (n=19), antipsychotics (n=38), anxiolytics (n=21), sedatives (n=22), antidepressants (n=35), anesthetics (n=23), and antidementia drugs (n=11).

Conclusion. Chemotranscriptome analysis indicated the positive effect of CTC on neurotransmission, neuroprotection, lipid profile, and a higher neuronal susceptibility to other neuroactive drugs.

Effects of CDP-choline administration on learning and memory in REM sleep-deprived rats

Cytidine 5-diphosphocholine (CDP-choline) administration has been shown to improve learning and memory deficits in different models of brain disorders. In this study, effects of CDP-choline on the well known negative effects of Rapid Eye Movements (REM) sleep deprivation on learning and memory were investigated. Sleep deprivation was induced by placing adult male Wistar albino rats on 6.5 cm diameter platforms individually for 96 h according to flower pot method. Learning and memory performances were evaluated using Morris Water Maze (MWM) test during the same period of time. Saline or CDP-choline (100 µmol/kg, 300 µmol/kg or 600 µmol/kg) was administered intraperitoneally 30 min prior to the onset of MWM experiments. On completion of behavioral tests, rats were decapitated and hippocampi were assayed for total and phosphorylated Ca²⁺/calmodulin-dependent protein kinase II (tCaMKII and pCaMKII, respectively) and total antioxidant capacity. We observed that while REM sleep deprivation had no effect on learning, it diminished the memory function, which was associated with decreased levels of pCaMKII and total antioxidant capacity in the hippocampus. CDP-choline treatment blocked the impairment in memory function of sleep-deprived rats and, increased pCaMKII levels and total antioxidant capacity. These data suggest that CDP-choline reduces REM sleep deprivation-induced impairment in memory, at least in part, by counteracting the disturbances in biochemical and molecular biological parameters.

Cytidine 5'-diphosphocholine administration prevents peripheral neuropathic pain after sciatic nerve crush injury in rats

Background

Cytidine 5′-diphosphocholine (citicoline) has been shown to have beneficial effects in central nervous system injury as well as in motoric functional recovery after peripheral nerve injury. This study aimed to examine the effect of citicoline on prevention of neuropathic pain in a rat model of sciatic nerve crush injury.

Methods

Forty experimental rats were divided into four groups. In three groups, the right sciatic nerves were crushed in the mid-thigh region, and a gelatin sponge moistened with 0.4 or 0.8 mL of 100 µmol/L citicoline, or saline 0.4 mL in the control group, was applied. The fourth group of rats was sham-operated, ie the sciatic nerve was exposed with no crush. Functional assessments were performed 4 weeks after crush injury. von Frey filaments (100 g threshold) were used to assess neuropathic pain. In addition, the sciatic functional index and extensor postural thrust (EPT) tests were used to assess motoric function.

Results

The crush/citicoline 0.4 mL group had a lower percentage of pain (23.53%, n=17) compared with the crush/saline group (53.33%, n=15, P<0.005). The crush/citicoline 0.4 mL group also showed better motoric recovery, as seen in stronger EPT results (P<0.001). However, the sciatic functional index analysis did not show significant differences between groups (P=0.35). The crush/citicoline 0.8 mL group showed a higher percentage of pain (66.67%, n=18) and less EPT recovery. These results may be explained by more severe nerve injury due to compression with a larger administered volume.

Conclusion

In situ administration of 0.4 mL of 100 µmol/L citicoline prevents the occurrence of neuropathic pain and induces motoric recovery, evaluated by EPT test, 4 weeks after sciatic nerve injury.

CDP-choline modulates matrix metalloproteinases in rat sciatic injury

BACKGROUND

CDP-choline (cytidine-5'-diphosphocholine) improves functional recovery, promotes nerve regeneration, and decreases perineural scarring in rat peripheral nerve injury. The aim of the present study was to investigate the mechanism of action of CDP-choline with regard to matrix metalloproteinase (MMP) activity in the rat-transected sciatic nerve injury model.

MATERIALS AND METHODS

Male Wistar rats were randomized into Sham, Saline, and CDP-choline groups. Rats in Sham group received Sham surgery, whereas rats in Saline and CDP-choline groups underwent right sciatic nerve transection followed by immediate primary saturation and injected intraperitoneally with 0.9% NaCl (1 mL/kg) and CDP-choline (600 μg/kg), respectively. Sciatic nerve samples were obtained 1, 3, and 7 d after the surgery and analyzed for levels and activities of MMP-2 and MMP-9, levels of tissue inhibitor of metalloproteinases-1 (TIMP-1) and TIMP-3, and axonal regeneration.

RESULTS

CDP-choline treatment decreased the levels and activities of MMP-2 and MMP-9, whereas increasing levels of TIMP-1 and TIMP-3 significantly on the third and seventh day after injury compared to Saline group. In addition, CDP-choline administration resulted in new axon formation and formation and advancement of myelination on newly formed islets (compartments) of axonal regrowth.

CONCLUSIONS

Our data show, for the first time, that CDP-choline modulates MMP activity and promotes the expression of TIMPs to stimulate axonal regeneration. These data help to explain one mechanism by which CDP-choline provides neuroprotection in peripheral nerve injury.

Improved human visuomotor performance and pupil constriction after choline supplementation in a placebo-controlled double-blind study

Only few nutrients are known to enhance cognition. Here we explore whether visuomotor performance can be improved through the intake of the nutrient choline, an essential chemical compound in a vertebrate's diet. Choline is abundant in for example eggs and shrimps and many animal studies suggest that it serves as a cognitive enhancer. As choline is important for the communication between motor neurons and the control of skeletal muscles, we assumed that choline supplementation may have positive effects on action coordination in humans. A group of twenty-eight individuals ingested two grams of choline bitartrate or a placebo in two separate sessions. Seventy minutes post ingestion, participants performed a visuomotor aiming task in which they had to rapidly hit the centers of targets. Results showed that participants hit targets more centrally after choline supplementation. Pupil size (a cognition-sensitive biomarker) also significantly decreased after choline intake and correlated positively with the hit distance to the targets and the number of target misses, and negatively with reaction times. These findings point to a choline-induced bias towards action precision in the trade-off between speed and accuracy. The changes in pupil size suggest that choline uptake alters cholinergic functions in the nervous system.

Cardioprotective properties of citicoline against hyperthyroidism-induced reperfusion damage in rat hearts

Hyperthyroidism represents an increased risk factor for cardiovascular morbidity, especially when the heart is subjected to an ischemia/reperfusion process. The aim of this study was to explore the possible protective effect of the nucleotide citicoline on the susceptibility of hyperthyroid rat hearts to undergo reperfusion-induced damage, which is associated with mitochondrial dysfunction. Hence, we analyzed the protective effect of citicoline on the electrical behavior and on the mitochondrial function in rat hearts. Hyperthyroidism was established after a daily i.p. injection of triiodothyronine (at 2 mg/kg of body weight) during 5 days. Thereafter, citicoline was administered i.p. (at 125 mg/kg of body weight) for 5 days. In hyperthyroid rat hearts, citicoline protected against reperfusion-induced ventricular arrhythmias. Moreover, citicoline maintained the accumulation of mitochondrial Ca(2+), allowing mitochondria to reach a high transmembrane electric gradient that protected against the release of cytochrome c. It also preserved the activity of the enzyme aconitase that inhibited the release of cytokines. The protection also included the inhibition of oxidative stress-induced mDNA disruption. We conclude that citicoline protects against the reperfusion damage that is found in the hyperthyroid myocardium. This effect might be due to its inhibitory action on the permeability transition in mitochondria.

Neuroprotective effect of oral choline administration after global brain ischemia in rats

Choline - now recognized as an essential nutrient - is the most common polar group found in the outer leaflet of the plasma membrane bilayer. Brain ischemia-reperfusion causes lipid peroxidation triggering multiple cell death pathways involving necrosis and apoptosis. Membrane breakdown is, therefore, a major pathophysiologic event in brain ischemia. The ability to achieve membrane repair is a critical step for survival of ischemic neurons following reperfusion injury. The availability of choline is a rate-limiting factor in phospholipid synthesis and, therefore, may be important for timely membrane repair and cell survival. This work aimed at verifying the effects of 7-day oral administration with different doses of choline on survival of CA1 hippocampal neurons following transient global forebrain ischemia in rats. The administration of 400 mg/kg/day divided into two daily doses for 7 consecutive days significantly improved CA1 pyramidal cell survival, indicating that the local availability of this essential nutrient may limit postischemic neuronal survival.

Cytidine 5'-diphosphocholine ameliorates hyperoxic lung injury in a neonatal rat model

BACKGROUND

Bronchopulmonary dysplasia (BPD) is an important cause of morbidity. The aim of this study was to evaluate the preventive effect of cytidine 5'-diphosphocholine (CDP-choline) treatment on hyperoxic lung injury in a neonatal rat model.

METHODS

A total of 30 newborn pups were divided into control, hyperoxia, and hyperoxia + CDP-choline groups. After birth, pups in the control group were kept in room air and received saline injections, whereas those in hyperoxia and hyperoxia + CDP-choline groups were exposed to 95% O₂ and received daily injections of saline and CDP-choline throughout postnatal day 10, respectively. Histopathological scoring, radial alveolar count, lamellar body membrane protein expression, fibrosis, proinflammatory cytokine levels, lung tissue and bronchoalveolar lavage (BAL) fluid phospholipid content, and apoptosis were evaluated.

RESULTS

Hyperoxia-induced severe lung damage was reduced significantly by CDP-choline treatment. Radial alveolar count and lamellar body membrane protein expression were significantly recovered, and the number of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling-positive cells, active caspase-3 expression, and tissue proinflammatory cytokine levels were decreased by CDP-choline administration. Lung tissue and BAL phospholipid contents showed significant increases after CDP-choline administration.

CONCLUSION

These data show that CDP-choline ameliorates hyperoxic lung injury in a neonatal rat model. It may therefore be suggested that CDP-choline may be a novel therapeutic option for the prevention of BPD.

Cytidine diphosphate choline improves the outcome of cardiac arrest vs epinephrine in rat model

OBJECTIVES

Cytidine diphosphate choline (CDP-choline) is a cholinergic agent that can both stimulate the cholinergic pathway and increase blood pressure. We aimed to investigate the effects of CDP-choline on the outcome of cardiac arrest in comparison with epinephrine.

METHODS

This was a randomized prospective animal study. Cardiac arrest was induced by asphyxia in 45 rats. After 7 minutes of asphyxia, resuscitation was attempted. The rats were allocated to different groups treated with 2 mL/kg saline, 100 μg/kg epinephrine, or 250 mg/kg CDP-choline. The hemodynamic parameters were monitored for 2 hours after resuscitation, and cardiac function was evaluated by echocardiography 2 hours after resuscitation. The hearts were harvested at the end of monitoring for histologic evaluation.

RESULTS

Epinephrine and CDP-choline improved the rate of return of spontaneous circulation and blood pressure during cardiopulmonary resuscitation; however, postresuscitation cardiac function in the CDP-choline and placebo groups was better than in the epinephrine group. Compared with the epinephrine group, less myocardial and mitochondrial injury was observed by electron microscopy in the CDP-choline and placebo groups; the level of superoxide dismutase and malondialdehyde indicated less peroxidative injury in the CDP-choline and placebo groups. Cytidine diphosphate choline and placebo also preserved connexin 43 when compared with epinephrine.

CONCLUSION

When administered during resuscitation, CDP-choline increased the rate of return of spontaneous circulation similarly to epinephrine. In addition, it did not increase the severity of myocardial injury and postresuscitation myocardial dysfunction, whereas epinephrine appeared to be harmful.

CDP-choline reduces severity of intestinal injury in a neonatal rat model of necrotizing enterocolitis

BACKGROUND

Cytidine 5'-diphosphocholine (CDP-choline) is an endogenous intermediate in the biosynthesis of phosphatidylcholine, a contributor to the mucosal defense of the intestine. The aim of this study was to evaluate the possible cytoprotective effect of CDP-choline treatment on intestinal cell damage, membrane phospholipid content, inflammation, and apoptosis in a neonatal rat model of necrotizing enterocolitis (NEC).

METHODS

We divided a total of 30 newborn pups into three groups: control, NEC, and NEC + CDP-choline. We induced NEC by enteral formula feeding, exposure to hypoxia-hyperoxia, and cold stress. We administered CDP-choline intraperitoneally at 300 mg/kg/d for 3 d starting from the first day of life. We evaluated apoptosis macroscopically and histopathologically in combination with proinflammatory cytokines in the gut samples. Moreover, we determined membrane phospholipid levels as well as activities of xanthine oxidase, superoxide dismutase, glutathione peroxidase, and myeloperoxidase enzymes and the malondialdehyde content of intestinal tissue.

RESULTS

Mean clinical sickness score, macroscopic gut assessment score, and intestinal injury score were significantly improved, whereas mean apoptosis score and caspase-3 levels were significantly reduced in pups in the NEC + CDP-choline group compared with the NEC group. Tissue proinflammatory cytokine (interleukin-1β, interleukin-6, and tumor necrosis factor-α) levels as well as tissue malondialdehyde content and myeloperoxidase activities were reduced, whereas glutathione peroxidase and superoxide dismutase activities were preserved in the NEC + CDP-choline group. In addition, NEC damage reduced intestinal tissue membrane phospholipids, whereas CDP-choline significantly enhanced total phospholipid and phosphatidylcholine levels. Long-term follow-up in additional experiments revealed increased body weight, decreased clinical sickness scores, and enhanced survival in CDP-choline-receiving versus saline-receiving pups with NEC lesions.

CONCLUSIONS

Our study reports, for the first time, beneficial effects of CDP-choline treatment on intestinal injury in a neonatal rat model of NEC. Our data suggest that CDP-choline may be used as an effective therapeutic agent to prevent NEC.

Intraperitoneal administration of CDP-choline or a combination of cytidine plus choline improves nerve regeneration and functional recovery in a rat model of sciatic nerve injury

OBJECTIVE

Topical cytidine-5'-diphosphocholine (CDP-choline) improves functional recovery and promotes nerve regeneration in sciatic nerve injury in rats. The aims of this study were to test whether systemic treatment with CDP-choline was effective in improving the recovery of injured sciatic nerve, and to determine whether the cytidine and/or choline moieties of CDP-choline contribute to its beneficial actions.

METHODS

Seventy Sprague-Dawley rats underwent a surgical procedure that involved transectioning and immediate surgical repairing of the right sciatic nerve. Rats were assigned to one of five groups and administered intraperitoneally 1 ml/kg of saline (control) or saline containing 600 μmol/kg of each of CDP-choline, cytidine, choline, or cytidine+choline.

RESULTS

Recovery in sciatic function index score was greater in rats treated with CDP-choline, choline, or cytidine+choline at 8 and 12 weeks after the interventions. Peripheral nerve regeneration evaluated by electromyography at 12 weeks was also greater in rats receiving CDP-choline (228% of control), choline (168% of control), or cytidine+choline (221% of control). Axon counts and axon density increased significantly following CDP-choline, choline, or cytidine+choline, respectively. Treatment with equivalent dose of cytidine failed to affect sciatic function index, electromyography, and axon counts. Treatment with CDP-choline, but not its metabolites improved nerve adherence and separability score.

CONCLUSION

These data show that intraperitoneal CDP-choline, as well as the combination of its metabolites, cytidine+choline, improves functional recovery and promotes regeneration of injured sciatic nerves in rats. CDP-choline also improves nerve adherence and separability.

From brain to food: analysis of phosphatidylcholins, lyso-phosphatidylcholins and phosphatidylcholin-plasmalogens derivates in Alzheimer's disease human post mortem brains and mice model via mass spectrometry

Alzheimer's disease (AD) is a devastating neurodegenerative disorder characterized by extracellular senile plaques mainly consisting of Aβ, a 40-42 amino acid long peptide, and intracellular neurofibrillary tangles, accompanied by an excessive loss of synapses. Recently evidence accumulated that nutrition, especially polyunsaturated fatty acids, influences AD pathogenesis. Especially mid-life food habits with the consumption of specific fatty acids (FA) appear to influence the disease risk. The timely separation between food intake and disease makes a direct correlation with detailed analysis of eating habits combined with accurate food analysis nearly unattainable. A possible solution to circumvent these difficulties is to investigate the FA composition in human post mortem brain. In this study we focused on the main phospholipids phosphatidylcholin (PC), phosphatidylcholin-plasmalogen (PC-PL) and lyso-phosphatidylcholin (lyso-PC) in AD brains compared to control brains. Frontal cortices, temporal cortices and cerebellum of 30 AD (mean 78 years) and 14 control aged matched brains (mean 77.4 years) as well as APP transgenic mice compared to control mice were analyzed using an AB Sciex 4000 Qtrap mass spectrometer utilizing a FIA MS/MS method. PC, PC-PL and lyso-PC metabolites were analyzed in respect to saturation level and FA composition. As expected, the majority of the lipid species showed no significant differences, but interestingly a few species revealed a highly significant reduction in AD brains. These FAs are potential candidates for further food analysis in respect to AD pathology. Additionally, we show that the method applied with multiple reaction monitoring (MRM) used for this study is suitable for semi quantitative analysis of small amounts (10 μl) of brain tissue.

CDP-choline-induced contractions in the mouse gastric fundus through purinoceptors and Rho/Rho-kinase signalling

AIMS

This study aimed to investigate the effects of cytidine-5'-diphosphocholine (CDP-choline), an endogenous lipid precursor, on the reactivity of the mouse gastric fundus and to determine the mechanism(s) mediating its effects.

MAIN METHODS

Possible contractile effect of CDP-choline (10(-5)-10(-2)M) was investigated in the absence and presence of a muscarinic receptor antagonist, atropine (3 × 10(-6)M), an acetylcholine esterase inhibitor, physostigmine (10(-6)M), a Na(+) channel blocker, tetrodotoxin (TTX, 3 × 10(-6)M), a Rho-kinase inhibitor, Y-27632 (10(-5) M), a purinoceptor antagonist, suramin (2 × 10(-4)M), a nitric oxide synthase inhibitor, N(G)-nitro-L-arginine (L-NA, 3 × 10(-4)M), a Ca(2+) channel blocker, nifedipine (10(-6)M), an α(7) nicotinic receptor antagonist, methyllycaconitine citrate (MLA, 10(-6)M) and a G protein (G(i/o)) inhibitor, pertussis toxin (PTX, 2 μg/ml). The metabolites of CDP-choline, namely choline (10(-4)-10(-2)M), cytidine 5'-triphosphate (CTP, 10(-5)-10(-2)M), cytidine (10(-5)-10(-2)M) and cytidine monophosphate (CMP, 10(-3)-10(-2)M) were also tested. Besides, phosphorylation of MYPT1, which indicates Rho-kinase activity, was also detected.

KEY FINDINGS

CDP-choline produced contractions in a concentration-dependent manner. The contractions were not affected by atropine, physostigmine, TTX, PTX, MLA or L-NA. However, Y-27632, suramin or nifedipine partly reduced these contractions. CDP-choline increased phosphorylation of MYPT1. Among CDP-choline metabolites, cytidine had no contractile effects. However, choline induced considerable contractions, which were sensitive to atropine. CMP and CTP had also contractile activity, comparable to that of CDP-choline.

SIGNIFICANCE

These results suggest that CDP-choline produced contraction through, at least in part, purinoceptors and Rho/Rho-kinase signalling in the mouse gastric fundus.

Choline or CDP-choline attenuates coagulation abnormalities and prevents the development of acute disseminated intravascular coagulation in dogs during endotoxemia

Sepsis/endotoxemia causes platelet dysfunctions, abnormalities in coagulation and hemostatic mechanisms leading to organ dysfunctions and mortality. Choline prevents organ injury and improves survival during endotoxemia. The main objective of the present study was to determine the effects of choline or cytidine-5'-diphosphocholine (CDP-choline) on endotoxin-induced activation of coagulation and development of disseminated intravascular coagulation (DIC). Dogs were treated intravenously (i.v.) with saline, choline (20 mg/kg), or CDP-choline (70 mg/kg) three times with 4-h intervals starting 5 min before i.v. injection of endotoxin (1 mg/kg). Platelet counts and functions, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, coagulation factors, D-dimer and antithrombin (AT) were measured before and at 0.5-96 h after endotoxin. Circulating platelet, fibrinogen, coagulation factors and AT were decreased, whereas PT and aPTT were prolonged and serum D-dimer levels were elevated after endotoxin. Endotoxin-induced reductions in platelet counts and functions, fibrinogen, coagulation factors and AT were attenuated or blocked by choline or CDP-choline. Choline or CDP-choline blocked endotoxin-induced prolongation in PT and aPTT and enhancement in D-dimer. Elevated DIC scores were attenuated by choline and blocked by CDP-choline. Choline administration increased serum choline concentrations and caused bradycardia. Choline also increased choline and acetylcholine contents of circulating mononuclear cells and inhibited radioligand binding to their cholinergic receptors. These data show that choline administration, as choline chloride or CDP-choline, restores the abnormalities in the primary, secondary, and tertiary hemostasis and prevents the development of DIC during experimental endotoxemia in dogs probably by increasing both neuronal and non-neuronal cholinergic activity.

Choline or CDP-choline alters serum lipid responses to endotoxin in dogs and rats: involvement of the peripheral nicotinic acetylcholine receptors

We showed previously that choline administration protects dogs from endotoxin-induced multiple organ injury and platelet dysfunctions. Because sepsis/endotoxemia is associated with alterations in lipid metabolism, we have investigated whether choline or cytidine-5'-diphosphate choline, a choline donor, alters serum lipid responses to endotoxin in dogs and rats. In response to endotoxin, serum concentrations of triglycerides, choline-containing phospholipids, total cholesterol, and high-density lipoprotein cholesterol increased in a dose- and time-related manner. Administration of choline (20 mg/kg i.v. in dogs or 90 mg/kg i.p. in rats) or cytidine-5'-diphosphate choline (70 mg/kg i.v. in dogs) 5 min before and 4 and 8 h after endotoxin blocked or attenuated the increases in serum triglycerides, total cholesterol, and nonesterified fatty acids. Endotoxin-induced elevations in serum phospholipid levels did not change in rats and were enhanced in dogs by choline. In rats, serum lipid response to endotoxin was accompanied by severalfold elevations in serum levels of hepatorenal injury markers; their elevations were also blocked by choline. Pretreatment with hexamethonium blocked choline's effects on serum lipids and hepatorenal injury markers. Pretreatment with atropine blocked endotoxin-induced elevations in serum lipid and hepatorenal injury markers, but failed to alter choline's actions on these parameters. Choline treatment improved survival rate of rats in lethal endotoxin shock. In conclusion, these data show that choline treatment alters serum lipid responses to endotoxin and prevents hepatorenal injury during endotoxemia through a nicotinic acetylcholine receptor-mediated mechanism. Hence, choline and choline-containing compounds may have a therapeutic potential in the treatment of endotoxemia/sepsis.

Cardiovascular effect of peripheral injected melittin in normotensive conscious rats: Mediation of the central cholinergic system

Recently we demonstrated that centrally administrated melittin, a phospholipase A(2) (PLA(2)) activator, caused the pressor effect in normotensive, conscious rats. In the present study, we aimed to determine the cardiovascular effect of peripherally injected melittin and the involvement of the central cholinergic system on these effects in the normotensive conscious rats. For this reason, 250, 500 or 1000microg/kg doses of melittin were injected intraperitoneally to normotensive male Sprague Dawley rats. Melittin produced dose- and time-dependent increases in mean arterial pressure (MAP) and heart rate (HR). Both peripheral (5mg/kg; i.p.) and central (500microg; i.c.v.) pretreatment with indomethacin, nonselective inhibitor of cyclooxygenase (COX) 1 and 2, totally abolished cardiovascular effect of melittin. Intraperitoneal (i.p.) pretreatment with propranolol, a nonselective beta-adrenergic receptor blocker, completely abolished the tachycardic response to melittin. Also, the pressor effect of melittin was partially attenuated in these rats. In order to test the mediation of the central cholinergic system on the pressor and tachycardic effects of melittin, the rats were pretreated with atropine sulfate (10microg; i.c.v.), a cholinergic nonselective muscarinic receptor antagonist, mecamylamine (50microg; i.c.v.), a cholinergic nonselective nicotinic receptor antagonist, methyllycaconitine (10microg; i.c.v.) or alpha-bungarotoxin (10microg; i.c.v.), selective antagonists of alpha7 subtype nicotinic acetylcholine receptors (alpha7nAChRs) 15min prior to melittin (500microg/kg; i.p.) injection. Pretreatment with mecamylamine, methyllycaconitine or alpha-bungarotoxin partially diminished the pressor and tachycardic response to melittin in the normotensive conscious rats whereas pretreatment with atropine sulfate had no effect. In conclusion, our data demonstrate that peripherally administered melittin exerts a clear pressor and tachycardic effect by activating COX pathway. The activation of central cholinergic nicotinic receptors, predominantly alpha7nAChRs, appears to be involved in the pressor and tachycardic effects of the drug.

Choline, CDP-choline or phosphocholine increases plasma glucagon in rats: involvement of the peripheral autonomic nervous system

The present study was designed to test the effects of choline, cytidine-5'-diphosphocholine (CDP-choline) and phosphocholine on plasma glucagon concentrations in rats. Intraperitoneal (i.p.) injection of 200-600 micromol/kg of choline, CDP-choline or phosphocholine produced a dose-dependent increase in plasma glucagon and choline concentrations. Pretreatment with hexamethonium (15 mg/kg; i.p.), a peripherally-acting ganglionic nicotinic acetylcholine receptor antagonist, entirely blocked the increases in plasma glucagon by 600 micromol/kg of choline, CDP-choline or phosphocholine. The increases in plasma glucagon by these choline compounds was reduced significantly (P<0.01) by about 25% by pretreatment with atropine methylnitrate (2 mg/kg), a peripherally-acting muscarinic acetylcholine receptor antagonist. Blockade of central acetylcholine receptors did not alter the increase in plasma glucagon induced by i.p. choline (600 micromol/kg). While alpha(2)-adrenoceptor blockade or bilateral adrenalectomy attenuated the increase in plasma glucagon evoked by choline compounds, blockade of alpha(1)- or beta-adrenoceptors or chemical sympathectomy failed to alter this increase. Intracerebroventricular (i.c.v.) choline (1.5 micromol) administration also increased plasma glucagon; the effect was blocked by central pretreatment with a neuronal type nicotinic acetylcholine receptor antagonist, mecamylamine (50 microg; i.c.v.) or the neuronal choline uptake inhibitor, hemicholinium-3 (20 microg; i.c.v.). These data show that choline, CDP-choline or phosphocholine increases plasma glucagon concentrations by increasing peripheral nicotinic and muscarinic cholinergic neurotransmissions. Central choline also increases plasma glucagon by augmenting central nicotinic cholinergic neurotransmission by acting presynaptically. Stimulation of adrenal medullary catecholamine release and subsequent activation of alpha(2)-adrenoceptors are mainly involved in the increase in plasma glucagon induced by choline, CDP-choline or phosphocholine.