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2,838 result(s) for "Memory Disorders - blood"
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Adjunctive raloxifene treatment improves attention and memory in men and women with schizophrenia
There is increasing clinical and molecular evidence for the role of hormones and specifically estrogen and its receptor in schizophrenia. A selective estrogen receptor modulator, raloxifene, stimulates estrogen-like activity in brain and can improve cognition in older adults. The present study tested the extent to which adjunctive raloxifene treatment improved cognition and reduced symptoms in young to middle-age men and women with schizophrenia. Ninety-eight patients with a diagnosis of schizophrenia or schizoaffective disorder were recruited into a dual-site, thirteen-week, randomized, double-blind, placebo-controlled, crossover trial of adjunctive raloxifene treatment in addition to their usual antipsychotic medications. Symptom severity and cognition in the domains of working memory, attention/processing speed, language and verbal memory were assessed at baseline, 6 and 13 weeks. Analyses of the initial 6-week phase of the study using a parallel groups design (with 39 patients receiving placebo and 40 receiving raloxifene) revealed that participants receiving adjunctive raloxifene treatment showed significant improvement relative to placebo in memory and attention/processing speed. There was no reduction in symptom severity with treatment compared with placebo. There were significant carryover effects, suggesting some cognitive benefits are sustained even after raloxifene withdrawal. Analysis of the 13-week crossover data revealed significant improvement with raloxifene only in attention/processing speed. This is the first study to show that daily, oral adjunctive raloxifene treatment at 120 mg per day has beneficial effects on attention/processing speed and memory for both men and women with schizophrenia. Thus, raloxifene may be useful as an adjunctive treatment for cognitive deficits associated with schizophrenia.
Assessment of Plasma Amyloid-β42/40 and Cognitive Decline Among Community-Dwelling Older Adults
Plasma measurement of amyloid-β (Aβ) peptides has been associated with cognitive function, but evidence of its ability to identify cognitive decline is still scarce. To investigate the associations between plasma Aβ42/40 and cognitive decline over time among community-dwelling older adults with subjective memory concerns. This multicenter cohort study used data from volunteers in the 5-year study Multidomain Alzheimer Preventive Trial (MAPT). Participants were aged 70 years or older and observed for a median (interquartile range) of 3.9 (2.0-4.0) years. Recruitment of participants started in May 2008 and ended in February 2011. Follow-up ended in April 2016. Data analysis was conducted from April to October 2020. Plasma Aβ42 and Aβ40 were measured at 12 months for 448 participants (92.8%) and at 24 months for the rest. The moment of Aβ assessment was defined as the baseline for this study. Cognitive function was assessed at 12, 24, 36, 48, and 60 months by a composite cognitive score based on 4 tests; Mini Mental State Examination (MMSE); Clinical Dementia Rating, sum of boxes; and Alzheimer Disease Cooperative Study-Activities of Daily Living. Mixed-effect linear regressions were performed. A total of 483 participants (median [IQR] age, 76.0 [73.0-80.0]; 286 [59.2%] women) were analyzed. Of them, 161 (33.3%) were classified as low plasma Aβ42/40 (≤0.107). After adjusting for age, sex, education, body mass index, Geriatric Depression Scale score, apolipoprotein E ε4 genotype, and MAPT intervention groups, low plasma Aβ42/40 was associated with more pronounced decline in composite cognitive score (adjusted between-group mean difference: -0.20, 95% CI, -0.34 to -0.07; P = .004) and decline in MMSE score (adjusted between-group mean difference: -0.59; 95% CI, -1.07 to -0.11; P = .02) during the follow-up period compared with the group with an Aβ42/40 ratio greater than 0.107. In this study, low plasma Aβ42/40 was associated with more pronounced decline in cognitive function (measured by multiple outcomes) over time. Findings suggest that plasma Aβ42/40 may be used to identify people at risk of cognitive decline, being an alternative to more complex and expensive measures, such as positron emission tomography imaging or cerebrospinal fluid measurement.
Fish oil supplementation increases event-related posterior cingulate activation in older adults with subjective memory impairment
To determine the effects of long-chain omega-3 (LCn-3) fatty acids found in fish oil, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), on cortical blood oxygen level-dependent (BOLD) activity during a working memory task in older adults with subjective memory impairment. Randomized, double-blind, placebo-controlled study. Academic medical center. Healthy older adults (62–80 years) with subjective memory impairment, but not meeting criteria for mild cognitive impairment or dementia. Fish oil (EPA+DHA: 2.4 g/d, n=11) or placebo (corn oil, n=10) for 24 weeks. Cortical BOLD response patterns during performance of a sequential letter n-back working memory task were determined at baseline and week 24 by functional magnetic resonance imaging (fMRI). At 24 weeks erythrocyte membrane EPA+DHA composition increased significantly from baseline in participants receiving fish oil (+31%, p≤0.0001) but not placebo (−17%, p=0.06). Multivariate modeling of fMRI data identified a significant interaction among treatment, visit, and memory loading in the right cingulate (BA 23/24), and in the right sensorimotor area (BA 3/4). In the fish oil group, BOLD increases at 24 weeks were observed in the right posterior cingulate and left superior frontal regions during memory loading. A region-of-interest analysis indicated that the baseline to endpoint change in posterior cingulate cortex BOLD activity signal was significantly greater in the fish oil group compared with the placebo group during the 1-back (p=0.0003) and 2-back (p=0.0005) conditions. Among all participants, the change in erythrocyte EPA+DHA during the intervention was associated with performance in the 2-back working memory task (p = 0.01), and with cingulate BOLD signal during the 1-back (p = 0.005) with a trend during the 2-back (p = 0.09). Further, cingulate BOLD activity was related to performance in the 2-back condition. Dietary fish oil supplementation increases red blood cell omega-3 content, working memory performance, and BOLD signal in the posterior cingulate cortex during greater working memory load in older adults with subjective memory impairment suggesting enhanced neuronal response to working memory challenge.
Acute tryptophan depletion reduces kynurenine levels: implications for treatment of impaired visuospatial memory performance in irritable bowel syndrome
Rationale A visuospatial episodic memory impairment has recently been identified in irritable bowel syndrome. Increased tryptophan metabolism along the kynurenine pathway has also been reported in irritable bowel syndrome, which may play a role in altered cognitive performance as peripheral kynurenine can cross the blood brain barrier and lead to the production of neuroactive metabolites, which modulate glutamatergic and cholinergic signalling, key neurotransmitter systems involved in cognitive function. Objectives Utilising the acute tryptophan depletion (ATD) protocol, the aim of this study was to examine if manipulating peripheral levels of tryptophan regulates cognitive performance in irritable bowel syndrome and also to determine for the first time if the ATD protocol alters kynurenine supply to the central nervous system. Methods In this double-blind, placebo-controlled, crossover design study, nine female patients with irritable bowel syndrome and 14 matched female healthy controls participant completed a range of tests from the CANTAB ® following ATD and placebo. Plasma tryptophan and kynurenine, self-report measures of gastrointestinal symptoms, mood and arousal were determined pre- and post-treatment on each study day. Results Following placebo ( p  = 0.016) but not ATD ( p  > 0.05), patients with irritable bowel syndrome exhibited impaired visuospatial memory performance (Paired Associates Learning (PAL) test). In addition, ATD significantly decreased ( p  < 0.001) and placebo significantly increased ( p  < 0.001) plasma kynurenine levels in both groups. Conclusions Manipulating peripheral tryptophan and kynurenine levels using ATD modulates hippocampal-mediated cognitive performance in irritable bowel syndrome but not healthy controls. These data may have important implications for reducing cognitive impairment in irritable bowel syndrome.
Peripheral interleukin-6 levels and working memory in non-obese adults: A post-hoc analysis from the CALERIE study
This analysis aimed to investigate the association among interleukin 6 (IL-6) levels, caloric intake, and working memory and to explore the potential mediators of these associations using the public dataset from the Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy (CALERIE) clinical trial. The CALERIE study was designed to evaluate the effects of 2 y of prolonged caloric restriction in humans. Individuals were randomized to caloric restriction (CR; n = 145) or an ad libitum diet (AL; n = 75) for 2 y. The outcome measures used herein were spatial working memory tests (i.e., total number of errors and strategy). Generalized estimating equations were used to assess the effects of treatment, time, and potential moderators (e.g., sleep and physical activities). At baseline, there was an effect of hours of sleep, alcohol intake, and physical activities (i.e., mean total metabolic equivalent of task hours per day [MET-hours/day]) on IL-6 levels. The association between IL-6 and energy intake was moderated by MET-hours/day. The longitudinal analysis indicated that there was an effect of time, but not of treatment, on IL-6 levels, with decreasing values in both the CR and AL groups. Changes in IL-6 levels were associated with changes in working memory performance, but there were no between-group (i.e., CR vs. AL) differences. We observed an association between changes in IL-6 levels and improvement in spatial working memory tests. IL-6 was associated with higher caloric consumption, poorer sleep quality, and lower levels of physical activity.
Memory improvements in elderly women following 16 weeks treatment with a combined multivitamin, mineral and herbal supplement
Rationale There is potential for multivitamin supplementation to improve cognition in the elderly. This randomized, double-blind, placebo-controlled trial was conducted to investigate the effects of 16 weeks multivitamin supplementation (Swisse Women’s 50+ Ultivite ®) on cognition in elderly women. Methods Participants in this study were 56 community dwelling, elderly women, with subjective complaints of memory loss. Cognition was assessed using a computerized battery of memory and attention tasks designed to be sensitive to age-related declines to fluid intelligence, and a measure of verbal recall. Biochemical measures of selected nutrients, homocysteine, markers of inflammation, oxidative stress, and blood safety parameters were also collected. All cognitive and haematological parameters were assessed at baseline and 16 weeks post-treatment. Results The multivitamin improved speed of response on a measure of spatial working memory, however benefits to other cognitive processes were not observed. Multivitamin supplementation decreased levels of homocysteine and increased levels of vitamin B 6 and B 12 , with a trend for vitamin E to increase. There were no hepatotoxic effects of the multivitamin formula indicating this supplement was safe for everyday usage in the elderly. Conclusion Sixteen weeks ssupplementation with a combined multivitamin, mineral and herbal formula may benefit working memory in elderly women at risk of cognitive decline.
Peripheral endocannabinoid concentrations are not associated with verbal memory impairment during MDMA intoxication
Background Preclinical data have suggested involvement of the endocannabinoid (eCB) system in MDMA-induced memory impairment. Clinical research has shown that blockade of the 5-HT 2 receptor nulls memory impairment during MDMA intoxication. Interestingly, studies have demonstrated that the eCB and the 5-HT system interact. It was hypothesized that MDMA would cause an increase in eCB concentrations together with a decrease in memory performance, and that combining MDMA with a 5-HT 2 receptor blocker ketanserin would lead to a counteraction of the MDMA effects on eCB concentrations and memory. Methods Twenty healthy recreational polydrug users entered a double-blind placebo-controlled within-subject study. Participants received a pre-treatment (ketanserin 40 mg, placebo) followed 30 min later by a treatment (MDMA 75 mg, placebo). Verbal memory was tested by means of a 30-word learning test. Endocannabinoid concentrations (anandamide (2-AG); N -arachidonylethanolamine (AEA)) were assessed in blood at baseline, before (90 min post-treatment) and after cognitive tests (150 min post-treatment). Results Findings showed that MDMA impaired memory 90 min post-treatment in the word learning task. This effect was a replication of previous studies using the same dose of MDMA (75 mg) and the same learning paradigm. Contrary to our hypothesis, MDMA did not affect eCB concentrations, nor did ketanserin block MDMA-induced memory impairment. Ketanserin caused an increase in AEA concentrations, 180 min after administration. Conclusion Current findings suggest that peripherally measured endocannabinoids are not associated with the verbal memory deficit during MDMA intoxication. Trial registration number: NTR3691.
Moderating effect of working memory capacity on acute alcohol effects on BOLD response during inhibition and error monitoring in male heavy drinkers
Rationale While alcohol intoxication is known to increase disinhibited behavior, the degree to which disinhibition occurs appears to depend on a number of factors including executive functioning ability. However, the neural mechanisms by which individual differences in executive functioning lead to variable degrees of disinhibition remain unclear. Objectives The aim of the current study was to examine the neural mechanisms by which individual differences in working memory (WM) capacity moderate alcohol-induced disinhibition. Methods Seventeen heavy-drinking males participated in a within-subjects design in which two sessions were completed: an alcohol session (.82 g/kg) and a control session. Participants completed a go/no-go task while undergoing functional magnetic resonance imaging (fMRI) after ingestion of the control or alcohol beverage. WM capacity was measured using an operation span task. Results Significant interactions of session and WM capacity emerged in contrasts examining successful response inhibition within superior temporal gyrus and unsuccessful inhibition in regions within the default mode network. In all cases, individuals with low WM capacity demonstrated a relative decrease in blood oxygen level-dependent (BOLD) response during the alcohol compared to control session, whereas the high-WM-capacity group demonstrated relative increases in BOLD response in the alcohol compared to control session. Conclusions Low WM capacity appears to be associated with decreased neural response to signals indicating a need for behavioral control, an effect that may lead to increased difficulty with inhibiting responses and increased negative consequences from alcohol intoxication.
Involvement of Inferior Parietal Lobules in Prospective Memory Impairment during Acute MDMA (Ecstasy) Intoxication: An Event-Related fMRI Study
Prospective memory refers to the realization of delayed intentions. Several studies have shown that 3,4-methylenedioxy-methamphetamine (MDMA) users perform worse on measures of prospective memory as compared to nondrug users. Interpretation of these data may be limited because of polydrug use, psychosocial stressors, and increased psychopathology that have been reported in MDMA users. This study was designed to directly assess the pharmacological effect of MDMA on prospective memory and brain activity in a double-blind, placebo-controlled, cross-over study. Twelve recreational MDMA users received MDMA 75 mg and placebo and performed an objective prospective memory task during functional imaging. During prospective memory task performance subjects were engaged in a foreground task that consisted of a simple reaction time to visual stimuli (Go trials) and a prospective task of withholding a response during trials that were part of a dynamic memory set (No go trials). Behavioral data showed that a single dose of MDMA increased prospective memory failures in the No go trials, and that number of prospective memory failures was positively correlated to MDMA concentration in plasma. Functional imaging showed that MDMA decreased BOLD activation during Go trials in the thalamus (left), putamen (left), precuneus (left), and the inferior parietal lobules (bilateral), as compared to placebo. During No go trials, MDMA reduced BOLD deactivation in the inferior parietal lobules (bilateral), as compared to placebo. It is concluded that the loss of deactivation in inferior parietal lobules may account for increments in memory failures observed during MDMA intoxication.
Blood biomarkers for memory: toward early detection of risk for Alzheimer disease, pharmacogenomics, and repurposed drugs
Short-term memory dysfunction is a key early feature of Alzheimer’s disease (AD). Psychiatric patients may be at higher risk for memory dysfunction and subsequent AD due to the negative effects of stress and depression on the brain. We carried out longitudinal within-subject studies in male and female psychiatric patients to discover blood gene expression biomarkers that track short term memory as measured by the retention measure in the Hopkins Verbal Learning Test. These biomarkers were subsequently prioritized with a convergent functional genomics approach using previous evidence in the field implicating them in AD. The top candidate biomarkers were then tested in an independent cohort for ability to predict state short-term memory, and trait future positive neuropsychological testing for cognitive impairment. The best overall evidence was for a series of new, as well as some previously known genes, which are now newly shown to have functional evidence in humans as blood biomarkers: RAB7A, NPC2, TGFB1, GAP43, ARSB, PER1, GUSB, and MAPT. Additional top blood biomarkers include GSK3B, PTGS2, APOE, BACE1, PSEN1, and TREM2, well known genes implicated in AD by previous brain and genetic studies, in humans and animal models, which serve as reassuring de facto positive controls for our whole-genome gene expression discovery approach. Biological pathway analyses implicate LXR/RXR activation, neuroinflammation, atherosclerosis signaling, and amyloid processing. Co-directionality of expression data provide new mechanistic insights that are consistent with a compensatory/scarring scenario for brain pathological changes. A majority of top biomarkers also have evidence for involvement in other psychiatric disorders, particularly stress, providing a molecular basis for clinical co-morbidity and for stress as an early precipitant/risk factor. Some of them are modulated by existing drugs, such as antidepressants, lithium and omega-3 fatty acids. Other drug and nutraceutical leads were identified through bioinformatic drug repurposing analyses (such as pioglitazone, levonorgestrel, salsolidine, ginkgolide A, and icariin). Our work contributes to the overall pathophysiological understanding of memory disorders and AD. It also opens new avenues for precision medicine- diagnostics (assement of risk) as well as early treatment (pharmacogenomically informed, personalized, and preventive).