Red light-induced localized release of carbon monoxide for alleviating postoperative cognitive dysfunction.

Inflammation within the central nervous system (CNS), which may be triggered by surgical trauma, has been implicated as a significant factor contributing to postoperative cognitive dysfunction (POCD). The relationship between mitigating inflammation at peripheral surgical sites and its potential to attenuate the CNS inflammatory response, thereby easing POCD symptoms, remains uncertain. Notably, carbon monoxide (CO), a gasotransmitter, exhibits pronounced anti-inflammatory effects. Herein, we have developed carbon monoxide-releasing micelles (CORMs), a nanoparticle that safely and locally liberates CO upon exposure to 650 nm light irradiation. In a POCD mouse model, treatment with CORMs activated by light (CORMs + hv) markedly reduced the concentrations of interleukin (IL)-6, IL-1ß, and tumor necrosis factor-alpha (TNF-α) in both the peripheral blood and the hippocampus, alongside a decrease in ionized calcium-binding adapter molecule 1 in the hippocampal CA1 region. Furthermore, CORMs + hv treatment diminished Evans blue extravasation, augmented the expression of tight junction proteins zonula occludens-1 and occludin, enhanced neurocognitive functions, and fostered fracture healing. Bioinformatics analysis and experimental validation has identified Htr1b and Trhr as potential key regulators in the neuroactive ligand-receptor interaction signaling pathway implicated in POCD. This work offers new perspectives on the mechanisms driving POCD and avenues for therapeutic intervention.

La aplicación del saber médico. Hipertensión y daño cognitivo

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Introduction: High blood pressure (HBP) is the leading cause of death from cardiovascular disease. Despite the advances, the percentage of undiagnosed and untreated hypertensive patients is 58.4%. The evaluation of cognitive damage in HBP focuses on preventing stroke, while functional damage is ignored. This inadequate management may be multifactorial. The objective was to analyze the opinions that doctors have about the relationship between high blood pressure and cognitive damage. Methodology: Observational, descriptive, cross-sectional study developed in the period between August 2020 and August 2023. Analysis of data obtained from a self-administered, anonymous and voluntary questionnaire. Revealing information on the professional profile, knowledge of HBP, its link with cognitive impairment (CD), diagnosis and treatment. Results: 222 professionals were included, 215 (96.8%) agree with the existence of a link between HBP and other cardiovascular risk factors in CD, and 218 (98.1%) acknowledge assisting patients at risk of suffering from CD. The CD evaluation is carried out in selected cases by 132 (59.4%) participants and 59 (26.7%) always do it. Of those who perform evaluation, 103 (54%) use the Mini Mental State Examination (MMSE), 10 (5.2%) use the Montreal Cognitive Assessment (MoCA) and 9 (4.7%) use the Clock Drawing Test. Regarding the decrease in blood pressure in elderly patients and the link with risk of CD: 54 (24.3%) do not recognize risk and 65 (29.2%) recognize a moderate-high risk. In reference to the implication of the treatment of cardiovascular disease and CD: 217 (97.7%) recognized a beneficial effect. Discussion: Given the recognition of the link between HBP and CD, it would be expected that CD would be investigated in the vast majority, however only 26.7% always evaluate it. There is no consensus on the method, the MMSE being the most used, with a low application of the MoCA test and/or Clock Drawing Test, the latter being the ones that evaluate executive function, mostly altered in CD linked to HBP. Although the treatment of cardiovascular disease is recognized as beneficial with respect to CD, the control of HBP in older adults is considered risky. A diagnosis is made of a situation where a disparity is evident between what one recognizes as knowing and what one claims to do. Conclusions: The role of vascular disease in functional brain damage is recognized, considering it necessary to know the cognitive status of patients, however there is a low application of screening tests that evaluate executive function. In this context, a gap between medical knowledge and practice is shown.

Introdução: A hipertensão arterial (HA) é a principal causa de morte por doenças cardiovasculares. Apesar dos avanços, o percentual de hipertensos não diagnosticados e não tratados é de 58,4%. A avaliação do dano cognitivo na hipertensão concentra-se na prevenção do acidente vascular cerebral, enquanto o dano funcional é ignorado. Esse manejo inadequado pode ser multifatorial. É objetivo fue analisar a opinião dos médicos sobre a relação entre hipertensão arterial e danos cognitivos. Metodologia: Estudo observacional, descritivo, transversal desenvolvido no período entre agosto de 2020 e agosto de 2023. Análise de dados obtidos a partir de questionário autoaplicável, anônimo e voluntário. Revelar informações sobre o perfil profissional, conhecimento sobre a HA, sua ligação com o comprometimento cognitivo (DC), diagnóstico e tratamento. Resultados: Foram incluídos 222 profissionais, 215 (96,8%) concordam com a existência de ligação entre hipertensão e outros fatores de risco cardiovascular na DC e 218 (98,1%) reconhecem ajudar pacientes com risco de sofrer de D.C. A avaliação da DC é realizada em casos selecionados por 132 (59,4%) participantes e 59 (26,7%) a fazem sempre. Dos que realizam avaliação, 103 (54%) utilizam o Mini Exame do Estado Mental (MEEM), 10 (5,2%) utilizam a Avaliação Cognitiva de Montreal (MoCA) e 9 (4,7%) utilizam o Clock Drawing Test. Em relação à diminuição da pressão arterial em pacientes idosos e a ligação com o risco de DC: 54 (24,3%) não reconhecem risco e 65 (29,2%) reconhecem risco moderado-alto. Em referência à implicação do tratamento de doenças cardiovasculares e DC: 217 (97,7%) reconheceram o efeito benéfico. Discussão: Dado o reconhecimento da ligação entre hipertensão e DC, seria de esperar que a DC fosse investigada na grande maioria, no entanto apenas 26,7% sempre a avaliam. Não há consenso sobre o método, sendo o MEEM o mais utilizado, com baixa aplicação do teste MoCA e/ou Clock Drawing Test, sendo estes últimos os que avaliam a função executiva, majoritariamente alterada nos DC vinculados à HA. Embora o tratamento das doenças cardiovasculares seja reconhecido como benéfico em relação à DC, o controle da HA em idosos é considerado arriscado. É feito um diagnóstico de uma situação em que é evidente uma disparidade entre o que se reconhece como saber e o que se afirma fazer. Conclusões: O papel da doença vascular no dano cerebral funcional é reconhecido, considerando-se necessário conhecer o estado cognitivo dos pacientes, porém há baixa aplicação de testes de triagem que avaliam a função executiva. Nesse contexto, evidencia-se uma lacuna entre o conhecimento e a prática médica.

Mendelian Randomization Analysis to Assess Whether Magnetic Resonance Imaging Signs of Cerebral Small Vessel Disease Can Cause Cognitive Decline and Dementia.

OBJECTIVE: Cognitive decline and dementia have been linked to cerebral small vessel disease, so we explored using Mendelian randomization whether cerebral small vessel disease visible as 10 neuroimaging signs may cause cognitive decline and dementia. METHODS: We analyzed publicly available data from genome-wide association studies using two-sample Mendelian randomization involving inverse variance weighting, weighted median, MR-Egger, and MR-PRESSO approaches. RESULTS: Mendelian randomization suggested that cognitive decline can be caused by lacunar stroke (inverse variance weighting, ß = -0.012, 95% CI -0.024 to -0.001, P = 0.033). Furthermore, an elevated burden of white matter hyperintensities was associated with an increased risk of Dementia due to Parkinson's disease (inverse variance weighting, OR 2.035, 95% CI 1.105 to 3.745, P = 0.023). Notably, no significant associations were observed between neuroimaging markers of Cerebral Small Vessel Disease and other types of dementia. CONCLUSION: This Mendelian randomization study provides evidence that lacunar stroke and white matter lesions can cause cognitive decline, and that white matter hyperintensity may increase risk of dementia due to Parkinson's disease. These results underscore the need for further investigations into the neurocognitive effects of cerebral small vessel disease.

CUMS induces depressive-like behaviors and cognition impairment by activating the ERS-NLRP3 signaling pathway in mice.

BACKGROUND AND OBJECTIVE: Endoplasmic reticulum stress (ERS), as a primary defense mechanism against stress, is closely related to mental disorders, but its pathogenesis is still unclear. This research seeks to explore the influence of ERS-nucleotide-bound oligomerized domain-like receptor protein 3 (NLRP3) signaling on mice's depressive-like behaviors and cognitive impairment. DESIGN AND METHOD: We carried out a study on 32 male C57BL/6J mice to investigate how chronic unpredictable mild stress (CUMS) can give rise to depressive-like behaviors and cognitive dysfunction, randomly dividing them into control, model, inhibitor, and agonist groups. We utilized ELISA to quantify dopamine (DA) and 5-hydroxytryptamine (5-HT) levels. Using Nissl and hematoxylin and eosin (H&E) staining, we assessed the number and morphology of hippocampal neurons and cells. Western blot and immunofluorescence staining detected the changes in ERS and inflammation-related pathways in the hippocampus. RESULTS: CUMS could induce ERS and activate NLRP3 inflammasome, causing neuronal damage and histopathological changes, eventually leading to depressive-like behaviors and cognitive impairment in mice. The abnormal activation of NLRP3 inflammasome could be restored by ERS blocker 4-phenyl butyric acid (PBA), thus reducing neuronal damage, and ameliorating depressive-like behaviors and cognitive disorder in mice. CONCLUSION: Our study demonstrates a previously unknown link between ERS and NLRP3 inflammasome in CUMS mice. The ERS-NLRP3 signaling pathway may be activated by CUMS, potentially resulting in mice exhibiting depressive-like behaviors and cognitive dysfunction. Theoretical foundations for elucidating the pathogenesis of depression, as well as its prevention and treatment, will be established through the results.

The association of pre-operative biomarkers of endothelial dysfunction with the risk of post-operative neurocognitive disorders: results from the BioCog study.

INTRODUCTION: Endothelial dysfunction (ED) promotes the development of atherosclerosis, and studies suggest an association with age-related neurocognitive disorders. It is currently unclear whether ED is also associated with the risk of perioperative neurocognitive disorders. METHOD: We included 788 participants aged ≥ 65 years of the BioCog study. Patients were scheduled to undergo elective surgery with expected duration > 60 min. Blood was collected before surgery for measurement of 5 biomarkers of ED: asymmetric and symmetric dimethylarginine (ADMA; SDMA), intercellular and vascular adhesion molecule (ICAM-1, VCAM-1), and von Willebrand factor (vWF). Patients were monitored for the occurrence of postoperative delirium (POD) daily until the 7th postoperative day. 537 (68.1%) patients returned for a 3-month follow-up. Post-operative cognitive dysfunction (POCD) was defined from the change in results on a battery of 6 neuropsychological tests between baseline and 3 months, compared to the change in results of a control group during the 3-month interval. The associations of each of the 5 ED biomarkers with POD and POCD respectively were determined using multiple logistic regression analyses with adjustment for age, sex, surgery type, pre-morbid IQ, body mass index, hypertension, diabetes, HbA1C, triglyceride, total and HDL cholesterol. RESULTS: 19.8% of 788 patients developed POD; 10.1% of 537 patients had POCD at 3 months. Concentrations of ED biomarkers were not significantly associated with a POD. A higher VCAM-1 concentration was associated with a reduced POCD risk (adjusted odds ratio 0.55; 95% CI: 0.35-0.86). No further statistically significant results were found. CONCLUSION: Pre-operative concentrations of ED biomarkers were not associated with POD risk. We unexpectedly found higher VCAM-1 to be associated with a reduced POCD risk. Further studies are needed to evaluate these findings.

Hippocampal PDHA1 gene knockout inhibits the Warburg Effect leading to cognitive dysfunction and attenuates the beneficial effects of ZiBuPiYin Recipe on cognition.

ETHNOPHARMACOLOGICAL RELEVANCE: The attenuation of the Warburg effect is an important pathological feature of cognitive dysfunction, and enhancing the Warburg effect is conducive to improving cognitive function. However, the pathogenic mechanisms underlying cognitive dysfunction remain incompletely elucidated. ZiBuPiYin Recipe (ZBPYR) is a traditional Chinese herbal compound used clinically for the treatment of cognitive dysfunction with significant efficacy. Nonetheless, the molecular mechanism underlying its beneficial effects remains elusive. AIM OF THE STUDY: The objective of this study is to investigate whether the attenuation of the Warburg effect exists in a mouse model of cognitive dysfunction induced by knockout of the pyruvate dehydrogenase E1 component subunit alpha (PDHA1) gene in the hippocampus, as well as the interventional effect of ZBPYR. MATERIALS AND METHODS: Using mice with PDHA1 gene knockout in the hippocampus and their littermate control mice as study subjects, behavioral experiments were conducted to assess the impact of PDHA1 gene knockout on cognitive function and the interventional effect of ZBPYR. We detected the expression of the Warburg effect-associated rate-limiting enzymes and PI3K/AKT pathway-related proteins. Subsequently, in PC12 cells, we explored the effect of the Warburg effect on cell apoptosis as well as the role of PDHA1 in the regulation of the PI3K/AKT-Warburg effect and the potential mechanism of ZBPYR in improving cognitive function. RESULTS: Mice with knockout of the PDHA1 gene in the hippocampus exhibited cognitive dysfunction, inhibition of the PI3K/AKT pathway, reduction of the Warburg effect, and neuronal damage. In vitro experiments indicated that silencing of PDHA1 in the hippocampus inhibited the PI3K/AKT-Warburg effect, leading to cell apoptosis and mediated the effect of ZBPYR in improving cognitive function. CONCLUSION: Our data not only suggest that the hippocampal PDHA1-PI3K/AKT-Warburg effect may be involved in the pathogenesis of cognitive dysfunction, but also demonstrate that PDHA1 knockout can abolish the beneficial effects of ZBPYR on cognition. This research aids in unraveling the cause of cognitive dysfunction and, therefore, offers a promising and innovative therapeutic target for these patients.

Structural disruption in subjective cognitive decline and mild cognitive impairment.

Subjective cognitive decline (SCD) marks the initial stage in Alzheimer's disease continuum. Nonetheless, current research findings regarding brain structural changes in the SCD are inconsistent. In this study, 37 SCD patients, 28 mild cognitive impairment (MCI) patients, and 42 healthy controls (HC) were recruited to investigate structural alterations. Morphological and microstructural differences among the three groups were analyzed based on T1- and diffusion-weighted images, correlating them with neuropsychological assessments. Additionally, classification analysis was performed by using support vector machines (SVM) categorize participants into three groups based on MRI features. Both SCD and MCI showed decreased volume in left inferior parietal lobe (IPL) compared to HC, while SCD showed altered morphologies in the right inferior temporal gyrus (ITG), right insula and right amygdala, and microstructures in fiber tracts of the right ITG, lateral occipital cortex (LOC) and insula relative to MCI. Moreover, the volume in the left IPL, right LOC, right amygdala and diffusivity value in fiber tracts of right LOC were significantly correlated with cognitive functions across all subjects. The classification models achieved an accuracy of > 0.7 (AUC = 0.8) in distinguishing the three groups. Our findings suggest that SCD and MCI share similar atrophy in the IPL but show more differences in morphological and microstructural features of cortical-subcortical areas.

Acupuncture improves spatial learning and memory impairment caused by herpes simplex virus type-1 in rats through the p38 MAPK/CREB pathway.

BACKGROUND: Acupuncture can improve herpes simplex encephalitis (HSE), but the underlying mechanism is not clear. Therefore, we evaluated the cognitive function and apoptosis in hippocampus caused by herpes simplex virus type-1 (HSV-1) in rats after acupuncture and described the molecular mechanism. METHODS: Sprague-Dawley rats were induced into HSE models by HSV-1 infection. After 3 days, they received acupuncture at the acupoints of Xuanzhong (GB39), Baihui (GV20), Shenmen (HT7), Shenting (GV24), and Sanyinjiao (SP6), and/or intraperitoneal injection of the p38 MAPK inhibitor SB203580. Morris water maze test was performed on rats. The hippocampus of rats was obtained, and the expression of apoptosis-related genes in the tissues was detected by qRT-PCR. In addition, apoptosis-related proteins and proteins related to the p38 MAPK/CREB pathway in the tissues was detected by western blot. RESULTS: After HSV-1 induction, the rat's escape latency was increased, the time spent on the platform in the target quadrant and the number of platform crossings significantly decreased. In addition, there was an increase in apoptosis in the hippocampus, accompanied by elevated levels of p-p38 and decreased levels of p-CREB. However, these effects could be improved by acupuncture treatment. Interestingly, SB203580 plays a similar role to acupuncture, and acupuncture could further enhance the impacts of SB203580 on cognitive function and apoptosis in hippocampus in HSE rats. CONCLUSION: Acupuncture improves spatial learning and memory impairment caused by HSV-1 in rats. The functional mechanism of acupuncture may be through the p38 MAPK/CREB pathway.

Interactive effect of diabetes mellitus and subclinical MRI markers of cerebrovascular disease on cognitive decline and incident dementia: a memory-clinic study.

BACKGROUND: Cognitive impairment is an increasingly recognized comorbidity of diabetes, yet the mechanisms underlying this association remain poorly understood. This knowledge gap has contributed to conflicting findings regarding the impact of diabetes on long-term cognitive outcomes in older adults. The presence of cerebrovascular disease (CeVD) may potentially modify this relationship. However, interactive effect between diabetes and subclinical MRI markers of CeVD on cognitive trajectories and incident dementia remains unexplored. METHODS: A total of 654 participants underwent brain MRI at baseline, from whom 614 with at least one follow-up were selected for longitudinal analysis. Cognitive tests were performed annually up to 5 years. CeVD markers of interest were lacunes, white matter hyperintensities (WMHs), cerebral microbleeds (CMBs), cortical microinfarcts (CMIs), intracranial stenosis (ICS), and cortical infarcts. Blood-based Alzheimer biomarkers, including p-tau181 and p-tau181/Aß42 ratio, were used as indicators of Alzheimer pathology. RESULTS: At baseline, diabetes was associated with lower cognitive performance and higher burden of CeVD, but not p-tau181 or p-tau181/Aß42 ratio. Longitudinally, we found an interactive effect of diabetes and WMHs, rather than an independent effect of diabetes, on cognitive decline and dementia risk. Subgroup analyses showed association of diabetes with cognitive outcomes was stronger in participants with high WMHs load but non-significant in those with low WMHs load. Moreover, these associations remained unchanged after adjusting for blood-based Alzheimer biomarkers. CONCLUSIONS: The effect of diabetes on cognitive decline is contingent upon the presence of WMHs and independent of Alzheimer's pathology. This finding raises the possibility of utilizing WMHs as an imaging biomarker to identify diabetic subgroup at greater risk of developing cognitive impairment. Furthermore, therapeutic interventions targeting WMHs may prevent cognitive deterioration in older adults with diabetes.

Gut Microbiota and Probiotics in Perioperative Management: A Narrative Review.

The human gut is the abode of several complex and diverse microbes. It is a fact that the human brain is interconnected with the spinal cord and sense organs; however, there is also a possibility of a connection between the brain and the gut microbiome. The human gut can be altered in various ways, the principal method being the intake of prebiotics, probiotics and synbiotics. Can this alteration in the gut microbiome be clinically utilised in the perioperative period? We conducted a literature search related to this topic using databases and search engines (Medical Literature Analysis and Retrieval System Online {MEDLINE}, Embase, Scopus, PubMed and Google Scholar). The search revealed some preclinical and clinical studies in animals and humans that demonstrate the alteration of the gut microbiome with the use of anxiolysis, probiotics/prebiotics and other perioperative factors including opioids, anaesthetics and perioperative stress. The significant effects of this alteration have been seen on preoperative anxiety and postoperative delirium/cognitive dysfunction/pain. These effects are described in this narrative review, which opens up newer vistas for high-quality research related to the gut microbiome, gut-brain axis, the related signaling pathways and their clinical application in the perioperative period.

Lithium-induced cognitive dysfunction assessed over 1-year hospitalisation: A case report.

Introduction: Lithium-induced neurotoxicity is almost always reversible but can cause irreversible neurological sequelae, namely the syndrome of irreversible lithium-effectuated neurotoxicity (SILENT). As there is no definitive treatment for SILENT, caution is required when administering lithium. Reports on the effect of lithium-effectuated neurotoxicity on cognitive function are limited. We report a case in which high cognitive function was lost after lithium overdose and hardly recovered, as evaluated using multiple neuropsychological tests during a 1-year hospitalisation period. Patient presentation: A 52-year-old man on lithium medication with bipolar disorder was admitted to the intensive care unit because of lithium overdose. The patient achieved lucid consciousness after continuous haemodiafiltration. However, he could not move his body as desired or produce appropriate verbal expressions; thus, he was moved to our psychiatric ward, where his treatment continued. Management and outcome: After several months, the patient was diagnosed with SILENT owing to persistent motor and cognitive dysfunctions. Multiple neuropsychological tests were performed, and cognitive function was evaluated. The Neurobehavioural Cognitive Status Examination showed a worsening trend, and the full intelligence quotient of the Wechsler Adult Intelligence Scale-Third Edition was in the mild intellectual disability range. Conclusion: This is a clear case of cognitive dysfunction due to SILENT and is difficult to treat. Thus, it is crucial to prevent the onset of SILENT. Contribution: This report is valuable because it is one of the few to track changes in cognitive function over time in a patient with SILENT using objective measures over 1 year of hospitalisation.

Neuroprotection of celastrol against postoperative cognitive dysfunction through dampening cGAS-STING signaling.

Neuroinflammation is a central player in postoperative cognitive dysfunction (POCD), an intractable and highly confounding neurological complication with finite therapeutic options. Celastrol, a quinone methide triterpenoid, is a bioactive ingredient extracted from Tripterygium wilfordii with talented anti-inflammatory capacity. However, it is unclear whether celastrol can prevent anesthesia/surgery-evoked cognitive deficits in an inflammation-specific manner. The STING agonist 5,6-dimethylxanthenone-4-acetic acid (DMXAA) was used to determine whether celastrol possesses neuroprotection dependent on the STING pathway in vivo and in vitro. Isoflurane and laparotomy triggered cGAS-STING activation, caspase-3/GSDME-dependent pyroptosis, and enhanced Iba-1 immunoreactivity. Celastrol improved cognitive performance and decreased the levels of cGAS, 2'3'-cGAMP, STING, NFκB phosphorylation, Iba-1, TNFα, IL-6, and IFN-ß. Downregulation of cleaved caspase-3 and N-GSDME was observed in the hippocampus of POCD mice and HT22 cells after celastrol administration, accompanied by limited secretion of pyroptosis-pertinent pro-inflammatory cytokines IL-1ß and IL-18. DMXAA neutralized the favorable influences of celastrol on cognitive function, as confirmed by the activation of the STING/caspase-3/GSDME axis. These findings implicate celastrol as a therapeutic agent for POCD through anti-inflammation and anti-pyroptosis.

A Systematic Review of Antidepressants and Psychotherapy Commonly Used in the Treatment of Late Life Depression for Their Effects on Cognition.

Cognitive dysfunction is common in late life depression (LLD) and is a major risk factor for dementia. Recent studies show limited improvement in cognition with commonly employed treatments for LLD, contradicting the notion that cognition "returns to normal" with treatment. However, findings differ with the treatments used. The aim of this study is to perform a systematic review of studies of antidepressants and psychotherapies commonly employed in LLD to determine their effects on cognition, particularly processing speed, memory, and executive function. We searched for trials of acute phase treatment, in nondemented individuals 60 years and older with unipolar nonpsychotic Major Depressive Disorder, that assessed cognitive performance with neuropsychological tests before and after treatment. We compared the magnitude of change in cognition by examining within group effect sizes. Six antidepressant trials and two psychotherapy trials (both using Problem Solving Therapy)(PST) provided relatively comparable data that allowed for quantitative comparison. Nine other antidepressant trials provided descriptive findings. Sertraline and vortioxetine had significant positive effects on processing speed and memory. Duloxetine had significant effects on memory. The most selective SRIs-citalopram and escitalopram-had minimal effects on cognition and citalopram had adverse effects in depression nonresponders. PST had modest effects on processing speed and no effect on memory. Effects of practice and improvement in depression on cognition are examined. In all but one study, cognition was a secondary outcome and various quality indicators (e.g. blinding cognitive assessment to treatment) were often not reported. As a consequence, these findings must be considered preliminary.

Pharmacological Prevention of Postoperative Delirium in Adults: A Review of Recent Literature.

PURPOSE OF REVIEW: Postoperative delirium (POD) is a common complication that has important implications for surgical patients, often leading to both short- and long-term cognitive deficits, worse outcomes, and increased healthcare costs. Given these implications, there may be a benefit in reducing the incidence of POD. Pharmacologic interventions may have the potential to reduce the risk of a patient developing POD. RECENT FINDINGS: Recently studied therapies include dexmedetomidine, propofol, haloperidol, ketamine, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, acetaminophen, melatonin/ramelteon, corticosteroids, midazolam, physostigmine, and neostigmine. In addition, the implementation of regional anesthesia and reduction of overall anesthetic depth have been examined. Of these therapies, dexmedetomidine has been studied the most and has the most supporting evidence for prevention of POD, but current studies lack clarity on optimal dosing and timing of dexmedetomidine administration. Acetaminophen, corticosteroids, and melatonin/ramelteon are other plausible medications that have potential for reducing POD incidence, but they all require further investigation. Reduction of anesthetic depth and regional anesthetics are options for anesthetic management that show promise but still lack enough supporting evidence in recent literature to receive a strong recommendation. Future research should focus on identifying optimal strategies for the implementation of the pharmacological options listed, including doses and timing of administration. Attention should be given to dexmedetomidine given its promise demonstrated by recent literature.

MEF2C Alleviates Postoperative Cognitive Dysfunction by Repressing Ferroptosis.

BACKGROUND: Ferroptosis, a form of programmed cell death featured by lipid peroxidation, has been proposed as a potential etiology for postoperative cognitive dysfunction (POCD). Myocyte-specific enhancer factor 2C (MEF2C), a transcription factor expressed in various brain cell types, has been implicated in cognitive disorders. This study sought to ascertain whether MEF2C governs postoperative cognitive capacity by affecting ferroptosis. METHODS: Transcriptomic analysis of public data was used to identify MEF2C as a candidate differentially expressed gene in the hippocampus of POCD mice. The POCD mouse model was established via aseptic laparotomy under isoflurane anesthesia after treatment with recombinant adeno-associated virus 9 (AAV9)-mediated overexpression of MEF2C and/or the glutathione peroxidase 4 (GPX4) inhibitor RSL3. Cognitive performance, Nissl staining, and ferroptosis-related parameters were assessed. Dual-luciferase reporter gene assays and chromatin immunoprecipitation assays were implemented to elucidate the mechanism by which MEF2C transcriptionally activates GPX4. RESULTS: MEF2C mRNA and protein levels decreased in the mouse hippocampus following anesthesia and surgery. MEF2C overexpression ameliorated postoperative memory decline, hindered lipid peroxidation and iron accumulation, and enhanced antioxidant capacity, which were reversed by RSL3. Additionally, MEF2C was found to directly bind to the Gpx4 promoter and activate its transcription. CONCLUSIONS: Our findings suggest that MEF2C may be a promising therapeutic target for POCD through its negative modulation of ferroptosis.

Postoperative delirium: A tragedy for elderly cancer patients.

In this editorial, we comment on the article by Hu et al entitled "Predictive modeling for postoperative delirium in elderly patients with abdominal malignancies using synthetic minority oversampling technique". We wanted to draw attention to the general features of postoperative delirium (POD) as well as the areas where there are uncertainties and contradictions. POD can be defined as acute neurocognitive dysfunction that occurs in the first week after surgery. It is a severe postoperative complication, especially for elderly oncology patients. Although the underlying pathophysiological mechanism is not fully understood, various neuroinflammatory mechanisms and neurotransmitters are thought to be involved. Various assessment scales and diagnostic methods have been proposed for the early diagnosis of POD. As delirium is considered a preventable clinical entity in about half of the cases, various early prediction models developed with the support of machine learning have recently become a hot scientific topic. Unfortunately, a model with high sensitivity and specificity for the prediction of POD has not yet been reported. This situation reveals that all health personnel who provide health care services to elderly patients should approach patients with a high level of awareness in the perioperative period regarding POD.

Association of sleep quality with cognitive dysfunction in middle-aged and elderly adults: a cross-sectional study in China.

Objectives: Sleep is an indispensable part of human health, which can help us to restore physical strength, enhance immunity and maintain nervous system stability. The relationship between sleep quality and cognitive dysfunction is unclear, especially at the community population level. This study aims to explore the association between sleep quality and cognitive dysfunction. Methods: A total of 5,224 community residents were enrolled in this cross-sectional study. Cognitive function was assessed by the Mini-Mental State Examination (MMSE). Sleep quality was assessed by the multidimensional sleep questionnaire. Multivariate logistic regression was used to analyze the association between sleep quality and cognitive dysfunction. The adjusted models took into account relevant demographic, clinical, and sleep variables. Results: A total of 3,106 participants were enrolled in this study, of whom 463 (15%) had cognitive dysfunction. Total sleep duration, staying up, sleep latency, number of awakenings, and history of sleep medications were associated with cognitive dysfunction in unadjusted models, and these effects were consistent after adjustment. First, those who slept 6-7.9 h per day (OR = 0.57, 95% CI 0.40 to 0.80, p = 0.001) had a lower risk for cognitive dysfunction compared to those who slept less than 6 h per day. Second, participants who stayed up more than 10 times over the 3 months (OR = 1.90, 95% CI 1.20 to 3.00, p = 0.006) were more likely to suffer cognitive dysfunction than those who never stayed up. Third, we also found that participants with sleep latencies of 16-30 min were less likely to experience cognitive dysfunction than those with sleep latencies of less than 16 min after adjusting confounders (OR = 0.33, 95% CI 0.23 to 0.47, p < 0.001). Fourth, participants who woke up once (OR = 1.65, 95% CI 1.19 to 2.30, p = 0.003) and three or more times (OR = 2.34, 95% CI 1.25 to 4.36, p = 0.008) after falling asleep had a higher risk than those who did not wake up at night. Last, participants taking sleep medication (OR = 2.97, 95% CI 1.19 to 7.45, p = 0.020) were more vulnerable to cognitive dysfunction, relative to participants without taking any medications. Conclusion: Our results suggest that after adjustment for potential confounding variables, poor sleep quality is associated with cognitive dysfunction.

Dexmedetomidine for Postoperative Delirium Prevention in the Older Adult: An Integrative Review.

The brain and cognition are particularly vulnerable to anesthetic and surgical insults, with postoperative delirium being the most common postoperative complication in patients aged ≥ 65 years. The body releases psychoactive proinflammatory cytokines in response to surgical trauma, including interleukin-1ß, interleukin-6, and tumor necrosis factor-α. This promotes a porous blood-brain barrier, promoting postoperative cognitive dysfunction. Aging adults lose brain volume, cerebrospinal fluid, and dendritic synapses, thereby increasing neurologic stress and vulnerability to these surgical changes. Anesthetic technique influences the process, necessitating the importance of educated certified registered nurse anesthetists. Dexmedetomidine, a nonspecific α2-adrenergic receptor agonist, exhibits anti-inflammatory properties that counteract the proinflammatory mechanisms initiated by surgical insult. Additionally, dexmedetomidine mimics natural sleep pathways and reduces opioid dosing requirements, promoting cognitive preservation. While further research is required to establish an association with long-term effects, current literature indicates that dexmedetomidine may reduce postoperative delirium and cognitive dysfunction in older adults through various dosing regimens. This journal course reviews the pathophysiology of postoperative neurocognitive dysfunction and delirium, dexmedetomidine as an adjunct to mitigate these pathologic changes, and the current literature on dexmedetomidine's impact on postoperative delirium in older adults.

Investigating the relationship between cognitive impairment and brain white matter tracts using diffusion tensor imaging in patients with prolactinoma.

BACKGROUND: Cognitive impairment is known to occur in patients with prolactinoma, but the underlying mechanism is unclear. OBJECTIVE: To evaluate cognitive function in patients with prolactinoma and to investigate the basis of possible cognitive impairment in brain white matter changes using diffusion tensor imaging (DTI). METHODS: 37 consecutive patients with prolactinoma and 37 healthy controls of similar age, sex, and education were enrolled in the study. Hormone levels were determined in all participants, comprehensive neuropsychological testing was performed, and DTI was used to reconstruct and evaluate white matter tracts. RESULTS: In patients with prolactinoma, short- and long-term visual and verbal memory, attention, concentration, and executive and language functions were impaired compared to the healthy group. When comparing the DTI results, lower fractional anisotropy (FA) values were found in the patients' right uncinate fasciculus (R-UF), indicating neuronal damage. After applying the Bonferroni correction, the two groups had no significant difference in 42 tracts (p > 0.0012 for all). A positive correlation was found between poor FA scores on the R-UF and low scores on long-term memory, category and letter fluency tests. In addition, patients with hypoprolactinemia had the worst short-term memory scores, while normoprolactinemia had the best scores. Also, the poorer R-UF FA values were found in the patients with hypoprolactinemia and the highest in those with normoprolactinemia. CONCLUSION: This study is the first to investigate reasons for cognitive dysfunction in patients with prolactinoma by DTI. No significant structural changes were found in brain tracts of patients with prolactinoma. Still, there may be a link between potential damage in the R-UF and cognitive dysfunction, and further research is needed. In addition, the results showed that the development of hypoprolactinemia is associated with cognitive dysfunction and emphasized that overtreatment should be avoided.

A web-based resource for exercise training in children treated for brain tumours to improve cognitive sequelae: Development and usability.

Improving cognitive sequelae in children treated for brain tumours (CTBT) requires accessible interventions. While instructor-led exercise in a hospital setting is efficacious, it is not extended to communities. Objectives: We aimed to (i) develop a website with educational resources/tools for community health and fitness professionals (HFP) to deliver exercise for CTBT in community settings to improve cognition and (ii) assess its usability by community HFP. It was hypothesized that the website would be learnable, clear, satisfactory and efficient to deliver exercise. Methods: A scoping review determined the state of eHealth resources to support exercise for CTBT and identified knowledge and resource gaps. Three focus groups with HFP who served cancer survivors in hospital or community settings (n = 13) identified user needs; content analysis identified themes. Gaps from the scoping review and themes from focus groups informed website content. A questionnaire assessed its usability by community HFP (n = 4). Descriptive statistics inferred the website's learnability, clarity, satisfaction and efficiency. Open-ended responses identified issues. Results: The scoping review revealed a lack of eHealth resources supporting exercise to improve cognition in CTBT and education for HFP to deliver exercise. Six themes were identified in the focus groups. HFP rated the website as sufficiently learnable, clear, satisfactory and efficient. Two minor issues were reported and addressed. Conclusion: The website marks one of the first eHealth resources to increase accessibility of intervention to improve cognitive sequelae and ultimately quality of life in CTBT. HFP also gain access to education and tools to deliver exercise in community settings.