Amyloid-Independent Amnestic Mild Cognitive Impairment and Serum Apolipoprotein A1 Levels

Development and validation of a nomogram predictive model for cognitive impairment in cerebral small vessel disease: a comprehensive retrospective analysis

Background

Cerebral small vessel disease (CSVD) is a common neurodegenerative condition in the elderly, closely associated with cognitive impairment. Early identification of individuals with CSVD who are at a higher risk of developing cognitive impairment is crucial for timely intervention and improving patient outcomes.

Objective

The aim of this study is to construct a predictive model utilizing LASSO regression and binary logistic regression, with the objective of precisely forecasting the risk of cognitive impairment in patients with CSVD.

Methods

The study utilized LASSO regression for feature selection and logistic regression for model construction in a cohort of CSVD patients. The model's validity was assessed through calibration curves and decision curve analysis (DCA).

Results

A nomogram was developed to predict cognitive impairment, incorporating hypertension, CSVD burden, apolipoprotein A1 (ApoA1) levels, and age. The model exhibited high accuracy with AUC values of 0.866 and 0.852 for the training and validation sets, respectively. Calibration curves confirmed the model's reliability, and DCA highlighted its clinical utility. The model's sensitivity and specificity were 75.3 and 79.7% for the training set, and 76.9 and 74.0% for the validation set.

Conclusion

This study successfully demonstrates the application of machine learning in developing a reliable predictive model for cognitive impairment in CSVD. The model's high accuracy and robust predictive capability provide a crucial tool for the early detection and intervention of cognitive impairment in patients with CSVD, potentially improving outcomes for this specific condition.

The association between blood lipids and cognitive impairment in type 2 diabetes mellitus

OBJECTIVE

The study was performed to explore the association between blood lipids and cognitive impairment in patients with type 2 diabetes mellitus (T2DM).

METHODS

This study included 336 patients with T2DM. Relevant clinical data including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), apolipoprotein A1, apolipoprotein B were collected, and the Mini-Mental State Examination (MMSE) score and Montreal Cognitive Assessment (MoCA) score were used to assess the cognitive function in patients with T2DM.

RESULTS

Serum apolipoprotein A1 levels were significantly increased in T2DM patients with cognitive impairment compared with T2DM patients without cognitive impairment (p = 0.017). Serum apolipoprotein A1 levels were significantly negatively correlated with MoCA score (r = - 0.143, p = 0.009) and MMSE score (r = - 0.132, p = 0.016) in patients with T2DM. In multivariable-adjusted regression model, serum apolipoprotein A1 was independently associated with cognitive impairment in patients with T2DM (OR = 5.201, p = 0.024).

CONCLUSION

Serum apolipoprotein A1 is associated with cognitive impairment in patients with T2DM, but not TC, TG, HDL-C, LDL-C, and apolipoprotein B, indicating that increased serum apolipoprotein A1 may be a risk factor of cognitive impairment in patients with T2DM.

Apolipoproteins and Suicide: A Potential Psychiatric Biomarker

Every year around 800,000 people commit suicide, this represents one death every 40 s. In the search for possible biological biomarkers associated with suicide and/or psychiatric disorders, serum cholesterol levels have been extensively explored. Several studies indicate that cholesterol and associated proteins, especially apolipoproteins (Apos), may play an important role in the diagnosis, prognosis, and susceptibility of suicidal behavior. Here, we describe the current knowledge and findings in the relationship between apolipoproteins and suicide.HIGHLIGHTSThis is the first systematic review of Apos in relation to suicidal behavior.Dysregulations of Apos expression has been observed in patients with suicidal behavior.Apos seem to be associated with cognitive dysfunction in suicide attempters.ApoE is a potential biomarker regarding suicidal behavior.

Association of Circulating Apolipoprotein AI Levels in Patients With Alzheimer's Disease: A Systematic Review and Meta-Analysis

With the development of medicine, our research on Alzheimer's disease (AD) has been further deepened, but the mechanism of its occurrence and development has not been fully revealed, and there is currently no effective treatment method. Several studies have shown that apolipoprotein AI (ApoA-I) can affect the occurrence and development of Alzheimer's disease by binding to amyloid β (Aβ). However, the association between circulating levels of ApoA-I and AD remains controversial. We conducted a meta-analysis of 18 studies published between 1992 and 2017 to determine whether the ApoA-I levels in the blood and cerebrospinal fluid (CSF) are abnormal in AD. Literatures were searched in PubMed, EMBASE and Web of Science databases without language limitations. A pooled subject sample including 1,077 AD patients and 1,271 healthy controls (HCs) was available to assess circulating ApoA-I levels; 747 AD patients and 680 HCs were included for ApoA-I levels in serum; 246 AD patients and 456 HCs were included for ApoA-I levels in plasma; 201 AD patients and 447 HCs were included for ApoA-I levels in CSF. It was found that serum and plasma levels of ApoA-I were significantly reduced in AD patients compared with HCs {[standardized mean difference (SMD) = −1.16; 95% confidence interval (CI) (−1.72, −0.59); P = 0.000] and [SMD = −1.13; 95% CI (−2.05, −0.21); P = 0.016]}. Patients with AD showed a tendency toward higher CSF ApoA-I levels compared with HCs, although this difference was non-significant [SMD = 0.20; 95% CI (−0.16, 0.56); P = 0.273]. In addition, when we analyzed the ApoA-I levels of serum and plasma together, the circulating ApoA-I levels in AD patients was significantly lower [SMD = −1.15; 95% CI (−1.63, −0.66); P = 0.000]. These results indicate that ApoA-I deficiency may be a risk factor of AD, and ApoA-I has the potential to serve as a biomarker for AD and provide experimental evidence for diagnosis of AD.

Systematic Review Registration: PROSPERO, identifier: 325961.

Apolipoprotein A1, the neglected relative of Apolipoprotein E and its potential role in Alzheimer's disease

Lipoproteins are multi-molecule assemblies with the primary function of transportation and processing of lipophilic substances within aqueous bodily fluids (blood, cerebrospinal fluid). Nevertheless, they also exert other physiological functions such as immune regulation. In particular, neurons are both sensitive to uncontrolled responses of the immune system and highly dependent on a controlled and sufficient supply of lipids. For this reason, the role of certain lipoproteins and their protein-component (apolipoproteins, Apo's) in neurological diseases is perceivable. ApoE, for example, is well-accepted as one of the major risk factors for sporadic Alzheimer's disease with a protective allele variant (ε2) and a risk-causing allele variant (ε4). ApoA1, the major protein component of high-density lipoproteins, is responsible for transportation of excess cholesterol from peripheral tissues to the liver. The protein is synthesized in the liver and intestine but also can enter the brain via the choroid plexus and thereby might have an impact on brain lipid homeostasis. This review focuses on the role of ApoA1 in Alzheimer's disease and discusses whether its role within this neurodegenerative disorder is specific or represents a general neuroprotective mechanism.

Elevated Plasma Free Fatty Acid Susceptible to Early Cognitive Impairment in Type 2 Diabetes Mellitus

BACKGROUND

Elevated free fatty acid (FFA) induces lipotoxicity, attributed to diabetes and cognitive decline. Sterol regulatory element-binding protein-1c (SREBP-1c) regulates lipid metabolism.

OBJECTIVE

We investigated the roles of FFA in mild cognitive impairment (MCI) of type 2 diabetes mellitus (T2DM) patients and determine its association with rs11868035 polymorphism.

METHODS

We recruited 191 Chinese T2DM patients into two groups through Montreal Cognitive Assessment. Demographic and clinical data were collected, multiple domain cognitive functions were tested, plasma FFA levels were measured through ELISA, and SREBP-1c rs11868035 genotype was detected using the Seqnome method.

RESULTS

In comparison with the healthy-cognition group (n = 128), the MCI group (n = 63) displayed lower glucose control (p = 0.012) and higher plasma FFA level (p = 0.021), which were independent risk factors of MCI in T2DM patients in multivariate regression analysis (OR = 1.270, p = 0.003; OR = 1.005, p = 0.036). Additionally, the plasma FFA levels of MCI patients were positively correlated with Stroop color word test-C time scores (r = 0.303, p = 0.021) and negatively related to apolipoprotein A1 levels (r = -0.311, p = 0.017), which are associated positively with verbal fluency test scores (r = 0.281, p = 0.033). Both scores reflected attention ability and executive function. Moreover, the G allele carriers of rs11868035 showed higher digit span test scores than non-carriers in T2DM patients (p = 0.019) but without correlation with plasma FFA levels.

CONCLUSION

In T2DM, elevated plasma level of FFA, when combined with lower apolipoprotein A1 level portends abnormal cholesterol transport, were susceptible to early cognitive impairment, especially for attention and execution deficits. The G allele of SREBP-1c rs11868035 may be a protective factor for memory.

Therapeutic Strategies and Nano-Drug Delivery Applications in Management of Aging Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder in which the death of brain cells causes memory loss and cognitive decline. Existing drugs only suppress symptoms or delay further deterioration but do not address the cause of the disease. In spite of screening numerous drug candidates against various molecular targets of AD, only a few candidates, such as acetylcholinesterase inhibitors, are currently utilized as an effective clinical therapy. Currently, nano-based therapies can make a difference, providing new therapeutic options by helping drugs to cross the blood-brain barrier and enter the brain more effectively. The main aim of this review was to highlight advances in research on the development of nano-based therapeutics for improved treatment of AD.

Mitochondrial therapeutic interventions in Alzheimer's disease

Alzheimer's Disease (AD) is one of the most common age-related neurodegenerative diseases in the developed world. Treatment of AD is particularly challenging as the drug must overcome the blood brain barrier (BBB) before it can reach its target. Mitochondria are recognized as one of the most important targets for neurological drugs as the organelle is known to play a critical role in diverse cellular processes such as energy production and apoptosis regulation. Mitochondrial targeting was originally developed to study mitochondrial dysfunction and the organelles interaction with other sub-cellular organelles. The purpose of this review is to provide an overview of mitochondrial dysfunction and its role in late onset AD pathology. We then highlight recent antioxidant and enzymatic treatments used to alleviate mitochondrial dysfunction. Finally, we describe current applications of targeted mitochondrial delivery in the treatment of AD.

Targeting Early Dementia: Using Lipid Cubic Phase Nanocarriers to Cross the Blood⁻Brain Barrier

Over the past decades, a frequent co-morbidity of cerebrovascular pathology and Alzheimer's disease has been observed. Numerous published studies indicate that the preservation of a healthy cerebrovascular endothelium can be an important therapeutic target. By incorporating the appropriate drug(s) into biomimetic (lipid cubic phase) nanocarriers, one obtains a multitasking combination therapeutic, which targets certain cell surface scavenger receptors, mainly class B type I (i.e., SR-BI), and crosses the blood⁻brain barrier. This targeting allows for various cell types related to Alzheimer's to be simultaneously searched out for localized drug treatment in vivo.

Nanotherapy for Alzheimer's disease and vascular dementia: Targeting senile endothelium

Due to the complexity of Alzheimer's disease, multiple cellular types need to be targeted simultaneously in order for a given therapy to demonstrate any major effectiveness. Ultrasound-sensitive coated microbubbles (in a targeted lipid nanoemulsion) are available. Versatile small molecule drug(s) targeting multiple pathways of Alzheimer's disease pathogenesis are known. By incorporating such drug(s) into the targeted "lipid-coated microbubble" [LCM]/"nanoparticle-derived" [ND] (or LCM/ND) nanoemulsion type, one obtains a multitasking combination therapeutic for translational medicine. This multitasking therapeutic targets cell-surface scavenger receptors (mainly class B type I), or SR-BI, making possible for various Alzheimer's-related cell types to be simultaneously searched out for localized drug treatment in vivo. Besides targeting cell-surface SR-BI, the proposed LCM/ND-nanoemulsion combination therapeutic(s) include a characteristic lipid-coated microbubble [LCM] subpopulation (i.e., a stable LCM suspension); such film-stabilized microbubbles are well known to substantially reduce the acoustic power levels needed for accomplishing temporary noninvasive (transcranial) ultrasound treatment, or sonoporation, if additionally desired for the Alzheimer's patient.

Alzheimer’s Disease, Brain Injury, and C.N.S. Nanotherapy in Humans: Sonoporation Augmenting Drug Targeting

Owing to the complexity of neurodegenerative diseases, multiple cellular types need to be targeted simultaneously in order for a given therapy to demonstrate any major effectiveness. Ultrasound-sensitive coated microbubbles (in a targeted nanoemulsion) are available. Versatile small-molecule drug(s) targeting multiple pathways of Alzheimer’s disease pathogenesis are known. By incorporating such drug(s) into the targeted lipid-coated microbubble/nanoparticle-derived (LCM/ND) lipid nanoemulsion type, one obtains a multitasking combination therapeutic for translational medicine. This multitasking therapeutic targets cell-surface scavenger receptors (mainly scavenger receptor class B type I (SR-BI)), making it possible for various Alzheimer’s-related cell types to be simultaneously sought for localized drug treatment in vivo. Besides targeting cell-surface SR-BI, the proposed LCM/ND-nanoemulsion combination therapeutic(s) include a characteristic lipid-coated microbubble (LCM) subpopulation (i.e., a stable LCM suspension); such LCM substantially reduce the acoustic power levels needed for accomplishing temporary noninvasive (transcranial) ultrasound treatment, or sonoporation, if additionally desired for the Alzheimer’s patient.

The pleiotropic vasoprotective functions of high density lipoproteins (HDL)

The pleiotropic functions of circulating high density lipoprotein (HDL) on peripheral vascular health are well established. HDL plays a pivotal role in reverse cholesterol transport and is also known to suppress inflammation, endothelial activation and apoptosis in peripheral vessels. Although not expressed in the central nervous system, HDL has nevertheless emerged as a potential resilience factor for dementia in multiple epidemiological studies. Animal model data specifically support a role for HDL in attenuating the accumulation of β-amyloid within cerebral vessels concomitant with reduced neuroinflammation and improved cognitive performance. As the vascular contributions to dementia are increasingly appreciated, this review seeks to summarize recent literature focused on the vasoprotective properties of HDL that may extend to cerebral vessels, discuss potential roles of HDL in dementia relative to brain-derived lipoproteins, identify gaps in current knowledge, and highlight new opportunities for research and discovery.

Relation between plasma and brain lipids

PURPOSE OF REVIEW

This article evaluates recent experimental and human evidence regarding the involvement of lipids, lipoproteins, and apolipoproteins in neurodegenerative diseases, and reviews the current literature of the effects of cholesterol-lowering treatment on cognition.

RECENT FINDINGS

Plasma levels of traditional lipids and lipoproteins are not consistently associated with risk of dementia even though low plasma levels of apolipoprotein E, through unknown mechanisms, robustly predict future dementia. Experimental evidence suggests neuroprotective roles of several brain and cerebrospinal fluid apolipoproteins. Whether plasma levels of apolipoprotein E, or any other apolipoprotein with possible central nervous system and/or blood-brain barrier functions (apolipoproteins J, A-I, A-II, A-IV, D, C-I, and C-III) may become accessible biomarker components that improve risk prediction for dementia together with genetic risk variants and cardiovascular risk factors remains to be determined.

SUMMARY

Apolipoproteins with well established functions in peripheral lipid metabolism may play important roles for brain vascular health and Alzheimer's disease pathophysiology. Experimental work on lipids, lipoproteins, and apolipoproteins in the central nervous system together with robust prospective human studies will help to substantiate the drug target potential of these lipid components.

Association of EEG, MRI, and regional blood flow biomarkers is predictive of prodromal Alzheimer's disease

BACKGROUND

Thinning in the temporoparietal cortex, hippocampal atrophy, and a lower regional blood perfusion is connected with prodromal stage of Alzheimer's disease (AD). Of note, an increase of electroencephalography (EEG) upper/low alpha frequency power ratio has also been associated with these major landmarks of prodromal AD.

METHODS

Clinical and neuropsychological assessment, EEG recording, and high-resolution three-dimensional magnetic resonance imaging were done in 74 grown up subjects with mild cognitive impairment. This information was gathered and has been assessed 3 years postliminary. EEG recording and perfusion single-photon emission computed tomography assessment was done in 27 subjects. Alpha3/alpha2 frequency power ratio, including cortical thickness, was figured for every subject. Contrasts in cortical thickness among the groups were assessed. Pearson's r relationship coefficient was utilized to evaluate the quality of the relationship between cortical thinning, brain perfusion, and EEG markers.

RESULTS

The higher alpha3/alpha2 frequency power ratio group corresponded with more prominent cortical decay and a lower perfusional rate in the temporoparietal cortex. In a subsequent meetup after 3 years, these patients had AD.

CONCLUSION

High EEG upper/low alpha power ratio was connected with cortical diminishing and lower perfusion in the temporoparietal brain area. The increase in EEG upper/low alpha frequency power ratio could be helpful in recognizing people in danger of conversion to AD dementia and this may be quality information in connection with clinical assessment.