Low plasma epinephrine in elderly female subjects of dementia of Alzheimer type

Dysfunction of norepinephrine and its metabolites in Alzheimer's dementia - A review with meta-analysis

Some studies point locus coeruleus cell loss, the central nervous system main source of norepinephrine, to be one of the earliest neuropathological events of Alzheimer's disease (AD). However, there are conflicting reports regarding the level of norepinephrine and its metabolites (3-Methoxy-4-hydroxyphenylglycol (MHPG), 3,5-dihydroxyphenylglycine (DHPG) and 3,4 -dihydroxyphenylglycolaldehyde (DOPEGAL)) in AD patients. Uncover these alterations may be a key factor for understanding cognitive deficits and AD pathology. We review the literature that compare norepinephrine and its metabolites between AD patients and non-demented controls. A meta-analysis did not reveal significant statistical differences, but there was a trend towards a lower level of norepinephrine of AD, with almost no difference in MHPG in the cerebrospinal fluid. Regarding MHPG in plasma, DHPG and DOPEGAL we only performed a qualitative analyse due to the small or absent number of studies. These findings point to a decrease in norepinephrine, what is in line with locus coeluleus cell loss in AD. The absence of statistical difference and an equal level of MHGP could indicate a compensatory mechanism.

Catecholamines in Alzheimer's Disease: A Systematic Review and Meta-Analysis

Background and Purpose: Previous studies found inconsistent results regarding the relationship between Alzheimer's disease (AD) and catecholamines, such as dopamine (DA), norepinephrine (NE), and epinephrine (EPI). Therefore, the purpose of this study was to perform a systematic review and meta-analysis to evaluate the results of previous studies on this relationship.

Method: Literature retrieval of eligible studies was performed in four databases (Web of Science, PubMed, Embase, and PsycARTICLES). Standardized mean differences (SMDs) were calculated to assess differences in catecholamine concentrations between the AD groups and controls.

Results: Thirteen studies met the eligibility criteria. Compared with the controls, significant lower concentrations of NE (SMD = −1.10, 95% CI: −2.01 to −0.18, p = 0.019) and DA (SMD = −1.12, 95% CI: −1.88 to −0.37, p = 0.003) were observed in patients with AD. No difference was found in the concentrations of EPI between the two groups (SMD = −0.74, 95% CI: −1.85 to 0.37, p = 0.189).

Conclusion: Overall, these findings are in line with the hypothesis that reduced NE and DA may be an important indicator for AD (Registration number CRD42018112816).

Correlation between cognition and plasma noradrenaline level in Alzheimer's disease: a potential new blood marker of disease evolution

Recent evidence showing degeneration of the noradrenergic system in the locus coeruleus (LC) in Alzheimer's disease (AD) has motivated great interest in noradrenaline (NA) as a potential brain hallmark of the disease. Despite the current exploration of blood markers for AD, the deregulation of the plasma NA concentration ([NA]_plasma) in AD is currently not well understood. This retrospective study includes a cohort of 71 patients (32 AD patients, 22 with other dementia and 17 without dementia) who were given consultations for memory complaints in the Cognitive Neurology Center of Lariboisière (Paris) between 2009 and 2014. As previously described in brain tissue, we show for the first time a linear correlation between [NA]_plasma and Mini Mental State Examination (MMSE) score in AD patients. We observed that high [NA]_plasma in AD patients was associated with higher [Aβ_1-42]_CSF than in other AD patients with [NA]_plasma similar to NC patients. In parallel, we observed a lower (p-Tau/Tau)_CSF in AD patients with low [NA]_plasma than in non-AD patients with [NA]_plasma similar to [NA]_plasma in NC patients. Our data suggest that [NA]_plasma could be a potential biomarker of disease evolution in the context of AD and could possibly improve early diagnosis.

Apathy associated with neurocognitive disorders: Recent progress and future directions

INTRODUCTION

Apathy is common in neurocognitive disorders (NCDs) such as Alzheimer's disease and mild cognitive impairment. Although the definition of apathy is inconsistent in the literature, apathy is primarily defined as a loss of motivation and decreased interest in daily activities.

METHODS

The Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment (ISTAART) Neuropsychiatric Syndromes Professional Interest Area (NPS-PIA) Apathy workgroup reviewed the latest research regarding apathy in NCDs.

RESULTS

Progress has recently been made in three areas relevant to apathy: (1) phenomenology, including the use of diagnostic criteria and novel instruments for measurement, (2) neurobiology, including neuroimaging, neuropathological and biomarker correlates, and (3) interventions, including pharmacologic, nonpharmacologic, and noninvasive neuromodulatory approaches.

DISCUSSION

Recent progress confirms that apathy has a significant impact on those with major NCD and those with mild NCDs. As such, it is an important target for research and intervention.

Determination of catecholamines and their metabolites in rat urine by ultra-performance liquid chromatography-tandem mass spectrometry for the study of identifying potential markers for Alzheimer's disease

In order to investigate the potential links between catecholamines (CAs) and Alzheimer's disease (AD), rapid and sensitive ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS) methods in different ionization modes for the quantification of 14 CAs and their metabolites in rat urine without derivatization or complex sample pre-treatments were developed. After addition of the internal standard, isoproterenol, the urine samples were extracted by protein precipitation and separated on an Inertsil ODS-EP column (Shimadzu, Japan) at a flow of 1.0 ml min(-1). Tandem mass spectrometric detection was performed on a 4000Q UPLC-MS/MS in the multiple reaction monitoring mode with turbo ion spray source. Tyrosine, dopamine, noradrenaline, epinephrine, 3-methoxytyramine, normetanephrine and metanephrine were determined in positive mode, while 3,4-dihyroxy-L-phenylalanine (DOPA), 3,4-dihydroxyphenylacetic acid, DL-3,4-dihydroxymandelic acid, DL-3,4-dihydroxyphenyl glycol, homovanillic acid, DL-4-hydroxy-3-methoxymandelic acid and 4-hydroxy-3-methoxy-phenylglycol were determined in negative mode. The methods were examined and were found to be precise and accurate within the linearity range of the assays. The intra-day and inter-day precision and accuracy of the analytes were well within acceptance criteria (±15%). The mean extraction recoveries of analytes and internal standard were all more than 60%. The validated methods have been successfully applied to compare CAs profiles in normal and AD rats. The results indicated the urine levels of DL-3,4-dihydroxyphenyl glycol and 4-hydroxy-3-methoxy-phenylglycol in AD rats were significantly higher than those in the normal group, and the other CAs have an opposite performance. These may attribute to the difference of some enzyme activity between rats with AD and normal. Furthermore, this may be helpful in clinical diagnostics and monitor the efficacy of AD treatment.

Simultaneous determination of catecholamines and their metabolites related to Alzheimer's disease in human urine

A simple and specific high-performance liquid chromatography method coupled with fluorescence detection (HPLC-FL) has been developed for the simultaneous determination of L-3,4-dihydroxyphenylalanine, norepinephrine, dopamine, epinephrine and 3,4-dihydroxyphenylacetic acid in human urine. The samples were derivatized by 1,2-diphenylethylenediamine with isoprenaline as internal standard. The factors affecting the fluorescence yield were investigated, including the reaction and separation conditions. The catecholamine derivatives were separated on a Kromasil C(18) column with methanol and sodium acetate buffer as mobile phase. The limits of detection for all catecholamines ranged from 0.2 to 1.1 ng/mL. The linear ranges were from 2.5 to 200 ng/mL except 3,4-dihydroxyphenylacetic acid from 5 to 200 ng/mL. The intra- and interday RSDs for all catecholamines were 1.0-8.0 and 2.1-14%, respectively. The method was successfully applied to determine the catecholamines in human urine from 14 Alzheimer's disease patients and 14 healthy volunteers. It was concluded that the mean levels of catecholamines in urine of Alzheimer's disease patients were all lower than those in healthy volunteers. The cluster analysis and independent samples T-test were used to distinguish the Alzheimer's disease patients and healthy volunteers.

Effect of oral administration of zanapezil (TAK-147) for 21 days on acetylcholine and monoamines levels in the ventral hippocampus of freely moving rats

Zanapezil (TAK-147 (3-[1benzylpiperdin-4-yl]-1-(2,3,4,5-tetrahydro-1 H-1-benzazepin-8-yl) propan-1-one fumarate)) is a selective acetylcholine (ACh) esterase inhibitor under investigation as a drug for Alzheimer's disease (AD) treatment. In this study, the effects of TAK-147 at 2 mg kg(-1) p.o. for 21 days, compared to donepezil (E2020), on the levels of ACh, catecolamines and indoleamines were investigated in the ventral hippocampus (VH) of freely moving rats by microdialysis-high-performance liquid chromatography. The results revealed that the VH contains 92.05+/-21.97 fmol 20 microl(-1) ACh and the following monoamines levels (pg 30 microl(-1)), norepinephrine (NE) 1.92+/-0.39, epinephrine (Epi) 1.91+/-0.183, 3-methoxy-4-hydroxyphenylglycol (MHPG) 11.53+/-3.22, normetanephrine 3.26+/-0.61, dopamine (DA) 0.77+/-0.23, 3,4-dihydroxyphenylacetic acid (DOPAC) 3.37+/-1.01, homovanillic acid (4-hydroxy-3-methoxyphenylacetic acid; HVA) 4.04+/-0.93, 3-methoxytyramine 0.64+/-0.13, serotonin (5-HT) 0.73+/-0.16 and 5-hydroxyindoleacetic acid (5-HIAA) 313.15+/-18.42. On the 21st day and prior to the last dose, TAK-147 increased ACh, Epi, DA and 5-HT, whereas E2020 increased MHPG, Epi and DA. Following the last dose, TAK-147 increased NE, whereas E2020 increased NE, ACh and 5-HT in addition to their effects prior to the last dose. TAK-147 decreased HVA : DA ratio, but only marginally decreased DOPAC : DA and 5-HIAA : 5-HT ratios. On the other hand, E2020 decreased ratios of HVA : DA, DOPAC : DA (prior to the last dose), and 5-HIAA : 5-HT (90-180 min after the last dose). Both drugs decreased MHPG : NE only at 180 min after the last dose. The results also showed that TAK-147 increased Epi : NE ratio prior to and for 120 min following the last dose, whereas E2020 increased the ratio only before the last dose. The present results show that TAK-147 at a subthreshold dose could differentially increase ACh and 5-HT, compared to MHPG increased by E2020. The last dose of each drug could extend their effects to other monoamines. The increase of the monoamines levels, in addition to that on the ACh, and decrease of their oxidation could be of value in the treatment of the AD, other dementic diseases and the cohort neurological disorders depending on the type of the monoamine underlying the disorder.

Increase in epinephrine excretion is associated with cognitive decline in elderly men: MacArthur studies of successful aging

BACKGROUND

High stress hormone levels are associated with increased risk of cognitive decline in elderly individuals. However, the effect of late-life changes in stress hormone levels on cognitive decline risk has not been examined. Our objective was to investigate whether increase over time in urinary epinephrine excretion in older adults was associated with subsequent cognitive decline.

METHODS

Measurements were made on 154 high-functioning men and women, 70-79 years of age, in 1988, 1991, and 1995. Twelve-hour overnight urinary excretion of epinephrine (normalized by creatinine excretion to adjust for body size) was recorded in 1988 and 1991. Cognitive functioning was assessed in 1991 and 1995 by summary scores based on standard tests of language, memory, abstraction, spatial recognition, and spatial construction.

RESULTS

Compared to individuals whose epinephrine excretion decreased between 1988 and 1991, the individuals whose epinephrine excretion increased over the same period had greater subsequent declines in summary cognitive scores between 1991 and 1995. After adjusting for baseline epinephrine, baseline cognitive function, and relevant covariates, and stratifying by gender, increases in urine epinephrine were positively associated with cognitive decline only in men.

CONCLUSIONS

We conclude that increase in urinary excretion of epinephrine predicts subsequent cognitive decline in older men.

Involvement of the entorhinal cortex in the stress response to immobilization, but not to insulin-induced hypoglycaemia

Although the involvement of the limbic system in the neuroendocrine responses to some stressors has been documented, the specific role of the entorhinal cortex has not been elucidated. In this study, we investigated the involvement of the entorhinal cortex in stress responses. Fos immunoreactivity, a widely used marker for neuronal activation, was detected in the entorhinal cortex of rats subjected to immobilization stress, whereas no marked staining was observed in the entorhinal cortex of the control and insulin-induced hypoglycaemia groups. Lesion of the entorhinal cortex produced by ibotenic acid significantly attenuated the adrenocorticotropic hormone (ACTH) release evoked by immobilization; however, no significant change in ACTH release was observed in insulin-induced hypoglycaemia. No significant difference between entorhinal-lesioned rats and control rats was observed in blood glucose concentrations when subjected to either immobilization or to insulin-induced hypoglycaemia. Together, these results indicate that the entorhinal cortex is closely involved in the stress response to immobilization but not to insulin-induced hypoglycaemia.

The metabolism of plasma glucose and catecholamines in Alzheimer's disease

Several lines of evidence suggest that the cholinergic system in the hippocampus plays a pivotal roll in regulating the peripheral metabolism of glucose and catecholamines. The injection of cholinergic stimulators including neostigmine, the acetylcholine esterase inhibitor, into the third ventricle or the hippocampus induces the elevation of glucose or catecholamines in plasma in rats. Under stress conditions, release of acetylcholine in the hippocampus increases, which coincides with the elevation of plasma glucose and catecholamines. Age-related reduction in responsivity of the cholinergic system in the hippocampus has been well documented. The intrahippocampal neostigmine injection induces significantly attenuated responses in plasma glucose and catecholamines in rats, the finding suggested that changes in cholinergic system activity in the hippocampus could result in alteration of the peripheral metabolism of glucose and catecholamines. In Alzheimer's disease (AD), the most common type of dementia, degeneration of the hippocampal cholinergic system is one of the most robust pathological features. Measurement of plasma catecholamines during a fasting state in the groups of AD subjects, vascular dementia subjects, and non-demented control subjects showed significantly lower plasma epinephrine levels in the AD subjects.

Plasma cortisol levels in elderly female subjects with Alzheimer's disease: a cross-sectional and longitudinal study

We investigated the plasma cortisol levels at a fasting state in elderly female Alzheimer's disease (AD), vascular dementia (VD), and non-demented subjects (n=66, 28 and 21, respectively). Twenty-eight AD subjects were followed for 40 months. The plasma cortisol levels in AD and VD subjects were significantly higher than those of non-demented subjects at baseline. In AD subjects in relatively early stages of the disease [Mini-Mental State Examination (MMSE)], at baseline, high plasma cortisol led to rapid declines in MMSE scores over a 40-month period.