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Biomedical subjects

R Cacabelos

Publications and source records attributed to R Cacabelos.

At least 73 records · Page 4Linked to original sources
PubMed1994

Brain mapping activity and mental performance after chronic treatment with CDP-choline in Alzheimer's disease.

CDP-choline participates in brain phospholipid metabolism and acts as an endogenous intermediate in a biosynthetic pathway incorporating free choline into phosphatidylcholine and choline plasmalogens in several tissues, including the central nervous system (CNS). In patients with chronic cerebrovascular disorders, CDP-choline reduces the slow delta frequencies and increases alpha activity in spectral electroencephalogram analysis. We have studied the effect of CDP-choline (cytidine-S-diphosphate-choline; 1000 mg/day x 30 days, p.o.) on brain electrical activity mapping and mental performance in 19 Alzheimer's disease (AD) patients (10 males/9 females; age: 66.21 +/- 1.48 years; Mini-Mental State Examination (MMSE): 26.55 +/- 1.22, Spanish version max. score 35). EEG was registered from 19 electrodes placed according to the 10-20 system and digitalized online. Artefact-free 2-s periods were visually selected, submitted to a frequency analysis and averaged across periods. CDP-choline significantly decreased spectral amplitude in the theta band in F4, F8, and T4 electrodes, and did not modify relative power parameters in any of the frequency bands (delta, theta, alpha, beta) as compared to basal recordings. In patients with late-onset AD (LOAD; N = 6; age: 73.5 +/- 1.34 years; MMSE: 28.75 +/- 2.33), CDP-choline tended to increase relative alpha power in O1 and O2 electrodes. No changes were found in early-onset AD patients (EOAD; N = 13; age: 62.85 +/- 1.21 years; MMSE: 25.54 +/- 1.4). We detected a significant improvement in mental performance after 1 month of treatment with CDP-choline in patients with early-onset AD in whom brain electrical activity data correlated with cognitive parameters. It is likely that the bioelectrical changes induced by CDP-choline in AD are the result of its immunogenic and/or neurotrophic activity in the vicinity of the vascular microenvironment.

Aged↗
PubMed1994

Effects of CDP-choline on cognition and cerebral hemodynamics in patients with Alzheimer's disease.

CDP-choline (cytidine-5-diphosphate-choline) is an acetylcholine precursor frequently used in cerebrovascular disorders and psychoorganic syndromes. Furthermore, several authors have demonstrated the positive effects of CDP-choline on cognitive disorders and memory deficits. In the present study, the effects of CDP-choline (1000 mg/day, p.o. for 1 month) on cognition, evaluated by the Mini-Mental State Examination (MMSE) of Folstein et al., and on blood flow velocities, measured by transcranial Doppler ultrasonography (TCD), were investigated in patients with Alzheimer's disease: (AD, n = 20, age: 66.75 +/- 6.73 years, range: 57-78 yr). Cognitive function was measured by means of the MMSE in basal conditions (A) and after 1 month of treatment with CDP-choline (C). TCD measures were taken through the temporal window for right (MCA-R) and left (MCA-L) middle cerebral arteries with a 2 MHz pulsed transducer using a TC-2000S in basal conditions (A), 1 h after the administration of CDP-choline (B) and after 1 month of treatment with CDP-choline (C). MMSE scores were significantly increased (p < 0.005) in patients with early-onset Alzheimer's disease (EOAD) after CDP-choline treatment. Moreover, the orientation subtest significantly increased in the global group of AD patients (p < 0.01) and in EOAD patients (p < 0.02). Significant differences (p < 0.05) were also found in MCA-Land MCA-R measures between recordings. These results suggest that CDP-choline influences cognitive and cerebrovascular function in Alzheimer's disease, probably through a mechanism linked to an immunogenic and/or neurotrophic effect at the microvascular niche.(ABSTRACT TRUNCATED AT 250 WORDS)

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PubMed1994

Brain interleukin-1 beta in Alzheimer's disease and vascular dementia.

Recent investigations indicate that a neuroimmune reaction, associated with inflammatory mechanisms, can contribute in Alzheimer's disease (AD) to cell damage and neurodegeneration. Activation of microglial cells, expression of immunohistochemical markers of brain immune function, the presence of complement proteins in brain tissue and changes in cytokine production have been reported in AD. We have studied the concentration of interleukin-1 beta (IL-1 beta) in different regions of the central nervous system (CNS) in post-mortem samples from patients with AD or vascular dementia (VD) and in age-matched control subjects (CS). IL-1 beta levels were significantly higher in AD than in VD or CS in the frontal cortex, parietal cortex, temporal cortex, hypothalamus, thalamus and hippocampus. The highest increases in IL-1 beta levels were observed in the frontal cortex (CS = 0.75 +/- 0.045; AD = 2.47 +/- 0.12, p < 0.001; VD = 1.52 +/- 0.078 pg/mg, p < 0.001) and hippocampus (CS = 0.71 +/- 0.042; AD = 2.63 +/- 0.19, p < 0.001; VD = 1.21 +/- 0.23 pg/mg, p < 0.01). No significant changes were detected in the occipital cortex and cerebellum in either AD or VD. These results clearly demonstrate that demented patients show a generalized increment of IL-1 beta production in the CNS, with maximum response in those brain regions where AD neuropathology is most prominent. This overall increase in cytokine production might represent an early event in the activation of a neuroimmune cascade leading to cell death and neurodegeneration in brain regions where a primary cause (e.g., genetic, toxic, vascular) facilitates the induction of resting microglia for firing brain immune function.

Aged↗
PubMed1994

CDP-choline-induced blood histamine changes in Alzheimer's disease.

Histamine (HA) is a known neurotransmitter with a wide spectrum of biological actions at the central and peripheral levels. Recently, it has been found that HA is involved in the regulation of immune cell function, acting as an immunomodulator. A hyperactivation in the histaminergic system has been demonstrated in Alzheimer's disease (AD), including increased levels of HA in brain, serum, and cerebrospinal fluid of AD patients. In addition, changes in phospholipid metabolism and neuroimmune function have been reported in AD. CDP-choline (cytidine-5-diphosphate-choline) participates in the phospholipid metabolism pathway incorporating free choline into phosphatidyl-choline and choline plasmalogens in several tissues, including the central nervous system. In this study we have measured the concentration of HA in blood from patients with early-onset AD (EOAD) and late-onset AD (LOAD) under treatment with CDP-choline (1000 mg p.o. x30 days). HA was measured by high performance liquid chromatography (HPLC) with fluorometric detection. CDP-choline reduced the basal levels of blood HA in both EOAD and LOAD by 2-fold. The reduction in blood HA content was observed 2 h after CDP-choline administration and gradually progressed for 30 days of treatment. These results confirm the potential immunogenic effects of CDP-choline and also that an excess of HA might influence some etiopathogenic events in AD.

Administration, Oral↗
PubMed1993

Effect of CDP-choline on cognition and immune function in Alzheimer's disease and multi-infarct dementia.

The cholinergic dysfunction present in Alzheimer's disease (AD) might be due to a specific vulnerability of cholinergic neurons linked to neurotrophic imbalance, neuroimmune impairment, and/or direct effects of beta-amyloid deposition and NFT formation in ACh neurons. The presence of abnormal epitopes exposed on neuronal membranes may contribute to the activation of resting microglia initiating a neuroimmune cascade leading to cell destruction. According to this hypothesis, a multifactorial treatment in AD should produce: 1) inhibition of beta-amyloid and NFT formation; 2) restoration of neuronal membrane integrity; and 3) control of neuroimmune auto-aggression. Since interleukin-1 (IL-1) is an APP gene promoter showing a progressive increase in body fluids in parallel with mental deterioration in AD patients, we have studied the effects of CDP-choline on cognition, several biological parameters, and IL-1 beta production in AD and multi-infarct dementia (MID) in order to elucidate whether this compound alone or in combination with other drugs is able to restore immune function and improve mental performance in senile dementia.

Aged↗
PubMed1993

Increase of histidine decarboxylase activity in mice hypothalamus after intracerebroventricular administration of lipopolysaccharide.

The effect of intracerebroventricular (icv) administration of lipopolysaccharide on histidine decarboxylase activity and histamine content in the hypothalamus were investigated in male mice of ddY strain in vivo. Two-fold increase in histidine decarboxylase activity (HDC) was observed 4 h after administration of 50 mcg lipopolysaccharide, and HDC activity returned to the basal level within 12 h after injection. Furthermore, histamine contents showed a slight decrease at 1 and 2 h and a mild increase at 12 h after administration. However, changes in histamine content were not statistically significant. These results suggest that the increase of HDC activity in the hypothalamus by lipopolysaccharide may be involved in the central neuroimmune responses.

Animals↗
PubMed1993

Transcranial Doppler ultrasonography in senile dementia: neuropsychological correlations.

Blood flow velocities were measured in right and left middle cerebral arteries (MCAs) and in basilar artery (BA) on rest conditions by transcranial Doppler ultrasonography in three groups of patients: a) Alzheimer's disease patients (AD, N = 12, age = 63.5 +/- 6.6 years), b) patients with multi-infarct dementia (MID, N = 12, age = 72.8 +/- 9.0 years), and c) control subjects (CS, N = 12, age = 57.20 +/- 7.5 years). TCD measures were taken through the temporal window for MCA recordings, and transforaminal approach for BA recordings, with a 2 MHz ultrasonic probe using a TC-2000S (EME). A significantly (p < 0.05) decrease in TCD measures was found in right and left MCA and BA of dementia patients with respect to controls. Data analysis included a significant correlation between blood flow velocities and Hachinski scores (p < 0.016) in multi-infarct dementia patients. These results appear to show a general hypoperfusion pattern in the brain of senile dementia patients.

Aged↗
PubMed1992

Brain histamine: psychoneuroimmune regulator in physiological and pathological conditions.

HA is a biogenic amine widely distributed in the CNS, with neurons located in the posterior hypothalamus. HA acts as a neurotransmitter and/or neuromodulator regulating neuroendocrine and neuroimmune functions, circadian rhythms, sleep-wakefulness cycle, body temperature, centrally-mediated neurovegetative functions, cerebrovascular control, and behavior and learning. Changes in brain HA are observed in aging. High levels of HA in CSF and CNS of AD patients might reflect a reactive response to neuroimmune activation and tissue damage.

Aging↗
PubMed1992

Serum histamine in Alzheimer's disease and multi-infarct dementia.

Recent data indicate that a neuroimmune reaction might be responsible in part for neuronal death and cognitive deterioration in senile dementia. The potential involvement of brain histamine (HA) and interleukin-1 (IL-1) in this process has been previously documented. We have studied the concentration of serum HA in patients with Alzheimer's disease (AD) or multi-infarct dementia (MID) and in age-matched control subjects. Serum HA levels were significantly higher in AD (10.935 +/- 5.692 nM) and MID (8.521 +/- 3.44 nM) than in controls (5.533 +/- 2.567 nM) and correlated with mental performance as evaluated with the Mini-Mental State Examination (MMSE) (r = +0.493, p < 0.009). No correlation was found with cardiovascular parameters, cerebrovascular risk factors or age. Hyperactivation of the histaminergic system in AD at central and peripheral levels might reflect a neuroimmune reaction to brain tissue damage, a neurotrophic response, and/or a reactive process to regulate the IL-1 induced amyloid precursor protein (APP) overproduction.

Adult↗
PubMed1991

Topographic maps of brain electrical activity in primary degenerative dementia of the Alzheimer type and multiinfarct dementia.

The topography of the electroencephalographic (EEG) pattern of ten patients with primary degenerative dementia of the Alzheimer type, ten multiinfarct dementia patients, and ten age-matched controls was compared during three different behavioral conditions: resting condition with eyes open (EO), memorizing a list of words (M), and recalling the same list of words (R). Results indicate that the alpha frequency band does not show significant changes. On the other hand, the theta band could be considered an important factor in the differential diagnosis of the primary degenerative dementia of the Alzheimer type, showing a higher power over right posterior regions in this group of patients compared with the multiinfarct dementia patients under different behavioral conditions.

Aged↗
PubMed1991

Histidine decarboxylase inhibition induced by alpha-fluoromethylhistidine provokes learning-related hypokinetic activity.

The influence of brain histamine (HA) on learning and memory is not well understood, although some reports indicate that HA improves memory consolidation. We have studied the effects of alpha-fluoromethylhistidine (FMH) (100 mg/Kg, i.p.), which reduced by 60-80% the concentration of hypothalamic HA, on rat locomotor activity (LA) and learning in several experimental conditions in a computerized system. FMH reduced LA in an open field paradigm (OFP) 3 h after injection and tended to inhibit motor habituation after a 3-day trial. In a maze paradigm (MP), where the animals had to learn to avoid a foot-shock (1 mA), FMH reduced LA, rearing (2F), and jumping activity (JA). The peripheral administration of HA to control-trained rats reduced a learning index (N/Sts ratio) by 50%. According to these results, FMH diminished LA, 2F, and JA with no effect on habituation in MP. These observations might indicate that a moderate reduction in the levels of brain HA might enhance attention in solving visuo-spatial tasks under stressful stimuli.

Animals↗
PubMed1991

Interleukin-1 in Alzheimer's disease and multi-infarct dementia: neuropsychological correlations.

It has been reported that patients with Alzheimer's disease (AD) exhibit an overproduction of interleukin-1 (IL-1) in the cerebrospinal fluid and brain tissue. Since IL-1 appears to promote the expression of the beta-amyloid precursor protein (APP) gene, we have investigated the concentrations of serum IL-1 alpha and IL-1 beta and AD and multi-infarct dementia (MID) in order to evaluate whether IL-1 acts as a peripheral activating factor on cerebrovascular endothelial cells stimulating APP production. Serum IL-1 alpha levels did not differ significantly between healthy elderly subjects (110.7 +/- 23.3 pg/ml), early-onset AD (EOAD; 112.5 +/- 23.3 pg/ml), late-onset AD (LOAD; 89.2 +/- 17.6 pg/ml) or MID (116.8 +/- 50.4 pg/ml) patients. Serum IL-1 beta levels were also similar in controls (223.7 +/- 55.7 pg/ml), EOAD (223.1 +/- 79.5 pg/ml), LOAD (212.5 +/- 58.9 pg/ml) and MID (199.4 +/- 29.0 pg/ml). In LOAD a negative correlation between mental performance (MMS score), IL-1 alpha (r = -0.7728; p less than 0.0715) and IL-1 beta (r = -0.9214; p less than 0.0011) was observed. These results indicate that serum IL-1 levels are not altered in AD and MID; therefore, it is unlikely that blood-borne IL-1 influences APP production in the central nervous system (CNS). In conclusion, the neuroimmune dysfunction present in AD seems to be mainly concentrated in the CNS, with only minor immune alterations at the peripheral level.

Aged↗
PubMed1991

Cerebrospinal fluid interleukin-1 beta (IL-1 beta) in Alzheimer's disease and neurological disorders.

Recent studies indicate that patients with Alzheimer's disease (AD) exhibit an immune dysfunction at the central and peripheral levels. We have studied the concentration of IL-1 beta in the cerebrospinal fluid (CSF) of patients with AD, multi-infarct dementia (MID), normal pressure hydrocephalus (NPH), and multiple sclerosis (MS). CSF IL-1 beta levels were significantly higher in AD (131 +/- 17.33 pg/ml) than in MID (79.71 +/- 24.37 pg/ml, p less than 0.01), NPH (84.75 +/- 23.17 pg/ml, p less than 0.01), and MS (79.4 +/- 10.23 pg/ml, p less than 0.01). In patients with neurological disorders CSF IL-1 beta levels showed a progressive increase with age (r = +0.49, p less than 0.015). The concentration of IL-1 beta in CSF of demented patients correlated with mental deterioration (r = -0.476). According to these results we postulate that high levels of central IL-1 beta in AD might reflect a reactive neuroimmune response to: (a) abnormal epitopes exposed by lesioned neurons, (b) reactive microglia activated by exogenous and/or endogenous factors and (c) endogenous neurotrophic activation.

Aged↗