Search Results (409)

Alzheimer’s disease (AD) is the most common cause of cognitive decline. Among the various susceptibility genes, the gene of apolipoprotein E (APOE) is probably the most important. It may be present in three allelic forms, termed ε2, ε3 and ε4, and the most common genotype is the ε3/ε3. Recently, it has been observed that subjects with the ε4/ε4 genotype may show near-full penetrance of AD biology (pathology and biomarkers), leading to the suggestion that ε4 homozygosity may represent a distinct genetic type of AD. The aim of the present study was to investigate the role of ε4 homozygosity or heterozygosity in the presence or absence of the AD biomarker profile in patients with cognitive disorders in the Greek population. A total of 274 patients were included in the study. They underwent APOE genotyping and cerebrospinal fluid (CSF) biomarker profiling. The presence of ε4 was associated with a lower age of symptom onset and decreased amyloid biomarkers (irrespective to AD or non-AD profiles), and predicted the presence of an AD profile by a positive predictive value approaching 100%. In conclusion, the ε4 allele has a significant effect on the risk and clinical parameters of cognitive impairment and AD in the Greek population, while the ε4/ε4 genotype may be highly indicative of the (co)existence of AD in cognitively impaired patients. Full article

Background: TGF-β is an immunosuppressive cytokine. Its signaling pathway plays a role in anti-inflammatory responses. Coronary artery disease (CAD) is a clinical consequence of atherosclerosis, which manifests as chronic inflammation and involves platelet mediators, including TGF-β. The aim of this study is to validate the diagnostic utility of TGF-β levels in relation to classical and molecular risk factors for CAD. Methods: The study group included 25 women and 75 men, all aged up to 55 and 50 years, respectively, who had been diagnosed with early-onset CAD. Fasting blood samples were taken to measure plasma levels of TGF-β, sCD36, PCSK9, TNF, VEGF, IL-6, and E-selectin using the ELISA method. Furthermore, a full lipid profile, apolipoproteins (Lp(a), ApoA1, and ApoB), C-reactive protein (hsCRP), and blood morphology were analyzed at the Central Hospital Laboratory. A physical examination was also performed. Results: Positive associations were observed between TGF-β concentration and TNF, platelet count, PTC, and triglyceride levels. TNF and platelet concentration were significant independent predictors of increased plasma TGF-β levels. None of the clinical parameters showed statistically significant associations with plasma TGF-β concentration. Conclusions: Our research has demonstrated that TGF-β levels, including circulating TNF, triglycerides, and platelets, are linked to specific biochemical risk factors in early-onset CAD cases. Full article

Alzheimer’s disease (AD) and ischemic stroke (IS) are prevalent neurological disorders that frequently co-occur in the same individuals. Recent studies have demonstrated that AD and IS share several common risk factors and pathogenic elements, including an overlapping genomic architecture. However, the relationship between IS risk gene polymorphisms and AD has been less extensively studied. We aimed at determining whether IS risk gene polymorphisms were associated with the risk of AD and the severity of AD in AD patients. We utilized data of AD patients and normal controls (NCs) sourced from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohort. IS risk single nucleotide polymorphisms (SNPs) were identified through the most recent and largest IS genome-wide association study (GWAS) meta-analysis. Subsequently, we conducted SNP-based association analysis of IS-risk SNPs with the risk of AD, along with amyloid, tau, and neuroimaging for AD. The generalized multifactor dimensionality reduction (GMDR) model was used to assess the interactions among IS-risk SNPs and apolipoprotein E (ApoE) ε4. Protein–protein interactions (PPIs) of the IS-risk genes product and APOE were explored using the STRING database. Seven IS-risk SNPs were involved in the study. Five SNPs were found to be associated with at least one measurement of cerebrospinal fluid (CSF) levels of amyloid-beta 1–42 (Aβ₄₂), total tau (t-tau), and phosphorylated tau 181 (p-tau₁₈₁), as well as the volumes of the hippocampus, whole brain, entorhinal cortex, and mid-temporal regions. After multiple testing corrections, we found that T allele of rs1487504 contributed to an increased risk of AD in non-ApoE ε4 carriers. The combination of rs1487504 and ApoE ε4 emerged as the optimal two-factor model, and its interaction was significantly related to the risk of AD. Additionally, C allele of rs880315 was significantly associated with elevated levels of CSF Aβ₄₂ in AD patients, and A allele of rs10774625 was significantly related to a reduction in the volume of the entorhinal cortex in AD patients. This study found that IS risk SNPs were associated with both the risk of AD and AD major indicators in the ADNI cohort. These findings elucidated the role of IS in AD from a genetic perspective and provided an innovative approach to predict AD through IS-risk SNPs. Full article

Background: Inflammasomes regulate the activation of caspases resulting in inflammation; inflammasome activation is dysregulated in Alzheimer’s disease (AD) and plays a role in the pathogenesis of this condition. Glibenclamide, an anti-inflammatory drug, could be an interesting way to down-modulate neuroinflammation. Methods: In this pilot study we verified with ex vivo experiments whether a glibenclamide-loaded nanovector (GNV) could reduce the NLRP3-inflammasome cascade in cells of AD patients. Monocytes isolated from healthy controls (HC) and AD patients were cultured in medium, alone or stimulated with LPS + nigericin in presence/absence of GNV. ASC-speck positive cells and inflammasome-related genes, proteins, and miRNAs expressions were measured. The polymorphisms of ApoE (Apolipoprotein E), specifically rs7412 and rs429358, as well as those of NLRP3, namely rs35829419, rs10733113, and rs4925663, were also investigated. Results: Results showed that ASC-speck+ cells and Caspase-1, IL-1β, and IL-18 production was significantly reduced (p < 0.005 in all cases) by GNV in LPS + nigericin-stimulated cells of both AD and HC. Notably, the NLRP3 rs10733113 AG genotype was associated with excessive inflammasome-related gene and protein expression. GNV significantly down-regulates inflammasome activation in primary monocytes, at least at protein levels, and its efficacy seems to partially depend on the presence of the NLRP3 rs10733113 genotype. Conclusions: All together, these results showed that GNV is able to dampen inflammation and NLRP-3 inflammasome activation in an ex vivo monocyte model, suggesting a possible role for GNV in controlling AD-associated neuroinflammation. Full article

Apolipoprotein E (APOE) allele 4 (APOE4), one of the robust genetic risk factors for AD, has also been associated with cognitive decline in terms of memory, executive function, language, and global cognitive function. APOE genotype-stratified analysis can help to identify additional genetic loci which might be masked due to a strong effect of APOE4. We conducted a genome-wide meta-analysis in APOE2 carriers, APOE4 carriers, and APOE 3/3 homozygote groups among 2969 non-Hispanic Whites aged ≥ 65 years using slopes of decline over time across five cognitive domains (attention, language, executive function, memory, and visuospatial function) and global cognitive function. We identified novel genome-wide significant associations for decline in global cognitive function in the intergenic region between RNU7-66P/RNA5SP208 at rs116379916 (p = 1.44 × 10⁻⁹) in the APOE 3/3 group and for decline in language in the intergenic region between LINC0221/DTWD2 at rs13187183 (p = 3.79 × 10⁻⁸) in APOE4 carriers. A previously reported locus for decline in attention near RASEF at rs6559700 (p = 9.95 × 10⁻⁹) was found to be confined to the APOE 3/3 group. We also found two sub-threshold significant associations in the APOE 2 group for decline in attention (IL1RL2/rs77127114; p = 8.64 × 10⁻⁸) and decline in language (YTHDC2/KCNN2, rs116191836; p = 5.66 × 10⁻⁸). Our study points to potential biological pathways pertaining to specific domains within each APOE genotype group, and the findings suggest that immune-related pathways, plasma levels of polysaturated fatty acids, and bitter taste receptors may play roles in cognitive decline. Our findings enhance the understanding of cognitive aging and provide a framework for future studies. Full article

Background: High-density lipoprotein cholesterol (HDL-C) is known for its cardiovascular and neuroprotective effects, but its association with cognitive function remains unclear, particularly in relation to genetic factors such as apolipoprotein E ε4 (APOE4). We aimed to investigate the association between serum HDL-C levels and cognition and to examine the moderating effect of APOE4 on this relationship. Methods: This cross-sectional study included 196 dementia-free older adults (aged 65–90) recruited from a memory clinic and the community. Cognitive function was assessed across multiple domains using the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) battery. Serum HDL-C levels were measured, and APOE4 genotyping was performed. Multiple linear regression analyses were conducted, adjusting for age, sex, APOE4 status, education, diagnosis, vascular risk, nutritional status, physical activity, and blood biomarkers. Results: Higher HDL-C levels were significantly associated with better episodic memory (B = 0.109, 95% confidence interval [CI]: 0.029–0.189, p = 0.008) and global cognition (B = 0.130, 95% CI: 0.001–0.261, p = 0.049). These associations were significantly moderated by APOE4 status. In APOE4-positive individuals, HDL-C was strongly associated with both episodic memory (B = 0.357, 95% CI: 0.138–0.575, p = 0.003) and global cognition (B = 0.519, 95% CI: 0.220–0.818, p = 0.002), but no such associations were observed in APOE4-negative participants. Conclusions: This study indicates a significant association between serum HDL-C levels and cognitive function, particularly in episodic memory and global cognition, with APOE4 status potentially moderating this relationship. While these findings may suggest a protective role of HDL-C in individuals at increased genetic risk due to APOE4, they should be interpreted with caution given the cross-sectional design. Future longitudinal and mechanistic studies are warranted to clarify causality and potential clinical implications. Full article

Background/Objectives: Apolipoprotein E receptor-2 (apoER2) exists in various alternatively spliced forms, including variants that express apoER2 with or without exon 19 in the cytoplasmic domain. This study compared vascular response to endothelial denudation, as well as diet-induced atherosclerotic and metabolic diseases, between genetically modified mice that exclusively expressed the apoER2 splice variant with or without exon 19 to determine the impact of apoER2 exon 19 motif in cardiometabolic disease modulation. Methods: Vascular response to injury was assessed by measuring neointima area of the carotid arteries after endothelial denudation. The genetically modified mice were also fed a high-fat high-cholesterol diet for 16 weeks for the determination of body weight gain, glucose and insulin levels, glucose tolerance and insulin secretion. Additionally, adipose tissue inflammation was assessed by analysis of adipose gene expression, and atherosclerosis was characterized by measuring fatty lesion size in the whole aorta, as well as in the aortic roots. Results: The results showed that whereas the expression of either splice variant is sufficient to impede denudation-induced fibrotic neointima formation and complex necrotic atherosclerotic lesions, the expression of the apoER2 splice variant containing exon 19 is necessary for the complete protection of injury-induced neointima formation in the vessel wall. However, exclusive expression of either apoER2 cytoplasmic splice variant does not influence the early phase of atherogenesis. Additionally, the exclusive expression of apoER2 without exon 19 promotes adipocyte inflammation and accelerates diet-induced insulin resistance and glucose intolerance. Conclusions: These results indicate that the apoER2 cytoplasmic variants have distinct and cell type-specific roles in influencing cardiometabolic disease development. Full article

Background/Objectives: Having serum biomarkers available for cardiac transthyretin amyloidosis (ATTR-CA) would be beneficial for diagnosis and prognosis. This study aimed to identify potential ATTR-CA biomarkers through proteomic analysis. Patients and Methods: Serum proteomic analyses were conducted on 15 ATTR-CA patients before receiving treatment, 11 ATTR-CA patients who had received tafamidis treatment for at least six months, and 13 patients with suspected cardiac amyloidosis who were later ruled out. All patients underwent blood tests, standard 12-lead electrocardiography, transthoracic echocardiography, and ^99mTc-DPD scintigraphy. Results: Proteomic analysis revealed significant differences in protein levels among the study groups. Key findings revealed increased levels of several proteins, including ceruloplasmin, apolipoprotein E, SERPINA1, and cDNA FLJ54111 (which is highly similar to serum transferrin), in ATTR-CA patients before receiving specific treatment. There was also a reduction in prothrombin, transferrin, CD14, and alpha-2-macroglobulin. In the ATTR-CA group treated with tafamidis, elevated levels of SERPINA1, paraoxonase 1, and complement C2 were observed. Notably, levels of cDNA FLJ54111 and SERPINA3 were reduced in this group. Compared to the control group, patients with ATTR-CA exhibited higher levels of ceruloplasmin, SERPINA3, and VCAM1, as well as lower levels of ApoA-I, ApoA-II, clusterin, and gelsolin. Controls exhibited elevated levels of transthyretin and prothrombin. Conclusions: This study identified candidate serum biomarkers for diagnosing ATTR-CA and monitoring the effectiveness of tafamidis treatment. Full article

Apolipoprotein E (APOE) alleles play distinct roles in the pathogenesis of Alzheimer’s disease (AD), with APOEε4 being the strongest genetic risk factor for late-onset AD, while APOEε2 appears protective. Despite extensive research, the precise mechanisms by which APOE alleles contribute to AD pathology remain incompletely understood. Recent advances in multi-omics technologies and single-cell analyses have revealed that APOE alleles shape microglial phenotypes, thereby affecting amyloid clearance, inflammatory responses, tau pathology, and lipid metabolism. In this review, we provide a detailed overview of how APOE alleles differentially regulate microglial activation, inflammatory signaling, phagocytic activity, and lipid metabolism in the context of AD, with a particular focus on the APOEε4-mediated disruption of microglial homeostasis via pathways such as TREM2 signaling, NF-κB/NLRP3 activation, ACSL1 upregulation, and HIF-1α induction. These insights not only advance our understanding of APOE allele-specific contributions to AD pathology, but also highlight novel therapeutic strategies targeting the APOE–microglia axis. Full article

This study examined the relationships between mid-arm circumference (MAC) and calf circumference (CC) with cognitive performance, considering the moderating effect of apolipoprotein E ε4 allele (APOE4) status. Data from 196 older adults (65–90 years) in the General Lifestyle and AD (GLAD) study were analyzed. Cognitive performance was assessed using the CERAD neuropsychological battery, with episodic memory score (EMS) and non-memory score (NMS) as primary outcomes. Multiple linear regression analyses examined associations between MAC, CC, and waist circumference (WC) with cognition, adjusting for key covariates. Interaction effects with APOE4 status were also explored. Higher MAC (or MAC/WC) significantly correlated with better EMS, while higher CC (or CC/WC) correlated with better NMS, even after Bonferroni correction (P_B < 0.0125). These associations were stronger in APOE4-negative individuals but not significant in APOE4-positive participants. WC was not associated with cognitive measures. The results suggest that Upper- and lower-limb musculature may play distinct roles in cognitive function, with MAC linked to episodic memory and CC to non-memory cognition, particularly in APOE4-negative individuals. These findings highlight the potential of muscle health maintenance as a strategy for preserving cognitive function in aging populations. Full article

(1) Background: Heart failure (HF) and dementia are commonly associated with the elderly. A significant percentage of patients with HF are at high risk of cognitive decline and progression to dementia. Cognitive impairment is associated with both diseases. However, the molecules and mechanisms that affect the HF–dementia axis are poorly understood. (2) Objective: In this work, we aim to identify potential proteins that modulate HF and dementia. (3) Methods: We applied a pipeline using bioinformatic tools that robustly perform a literature search. (4) Results: Our results show that apolipoprotein E (APOE), c-reactive protein (CRP), interleukin 6 (IL6), renin (REN), and angiotensin-converting enzyme (ACE) proteins are important for maintaining homeostasis in the heart–brain axis. Additionally, deregulated levels of these proteins are associated with neuronal and cardiovascular diseases. (5) Conclusions: Our work highlights proteins that may help in understanding the pathophysiological relationship between HF and dementia. Moreover, these proteins may also be potential biomarkers and/or therapeutic targets. Full article

Background: Emerging evidence suggests a potential link between heavy metals and Alzheimer’s disease and related dementias (AD/ADRD). This study compiled epidemiological evidence from research published over the past 11 years on the impact of metals on AD/ADRD in women. Women have unique risk factors for late onset of AD/ADRD, in addition to genetic factors, apolipoprotein E allele (APOE4), and longer life expectancy. Furthermore, women are twice likely as men to experience depression, which increases their risk of developing AD/ADRD. Our narrative review underscored the necessity of a sex-specific approach to address women’s vulnerability to AD/ADRD. Methods: Electronic databases, including PubMed, Google Scholar, NIOSH Toxline, and Scopus, were thoroughly searched to identify primary epidemiological studies on older women exposed to metals and published between 2014 to 2024. Results: We identified 34 epidemiological studies that met the inclusion criteria. The findings revealed a complex interplay between environmental metals such as lead (Pb), cadmium (Cd), arsenic (As), manganese (Mn), selenium (Se), iron (Fe), zinc (Zn), copper (Cu), magnesium (Mg), and calcium (Ca) and the risk of AD/ADRD in women. Significant adverse effects were reported for Cu, Cd, As, Pb, and Mn while significant protective effects were found between Se, Fe, and Zn in blood and AD/ADRD among older women. However, some studies also reported no correlations. Conclusions: Overall, our review identified contrasting results regarding the effects of metals on AD/ADRD in women. Future studies should collect additional evidence to understanding the effects of heavy metals on AD/ADRD in women for developing preventive measures. Full article

Lipid metabolism disorders represent a significant risk factor for the pathogenesis of Alzheimer’s disease (AD). Apolipoprotein E (APOE) has been regarded as a pivotal regulator of lipid homeostasis in the central nervous system (CNS), with polymorphic alleles identified as genetic risk factors for late-onset AD. Despite advances in APOE research and the development of numerous pharmaceutical approaches targeting distinct APOE isoforms, there remain limited treatment approaches for AD that focus on lipid metabolic homeostasis. Consequently, it is necessary to reevaluate the lipid metabolic process in the CNS. Apolipoprotein A1 (APOA-I), a major component of high-density lipoprotein (HDL), plays a crucial role in reverse cholesterol transport from tissues to the liver to maintain lipid homeostasis. Over the past few decades, numerous studies have suggested a connection between reduced APOA-I levels and a higher risk of AD. APOA-I is synthesized exclusively in the liver and intestines, and there is a lack of conclusive evidence supporting its functional significance within the central nervous system, in contrast to APOE, which is produced locally by glial cells and neurons within the CNS. Moreover, APOA-I’s ability to penetrate the blood-brain barrier (BBB) is still poorly understood, which causes its significance in central lipid metabolism and AD pathophysiology to be mainly disregarded. Recent advancements in tracing methodologies have underscored the essential role of APOA-I in regulating lipid metabolism in the CNS. This review aims to elucidate the physiological functions and metabolic pathways of APOA-I, integrating its associations with AD-related pathologies, risk factors, and potential therapeutic targets. Through this discourse, we aim to provide novel insights into the intricate relationship between AD and APOA-I, paving the way for future research in this field. Full article

Glucose delivery to the brain requires transporters at the blood–brain barrier (BBB), whose downregulation may be associated with neuronal deficits in Alzheimer’s disease (AD). Whether this downregulation is due to reduced demand or primary BBB dysfunction remains unclear. We investigated novel 18F-Fluorodeoxyglucose Positron Emission Tomography (18F-FDG-PET) measures, namely ventricles (FDG_Ventricles) and cortical uptake (FDG_Cortex), and the FDG_Ventricles/FDG_Cortex ratio in 224 patients with AD compared to those in 35 controls (CTRLs). AD patients showed lower FDG_Cortex and FDG_Ventricles and higher cerebrospinal fluid (CSF) lactates than CTRLs. We found a positive correlation between FDG_Cortex and FDG_Ventricles in both groups, although this was less strong in AD patients (AD: r = 0.358; p < 0.001; CTRL: r = 0.516; p = 0.003). Multivariate regression analyses showed that only older age was associated with reduced FDG_Cortex and FDG_Ventricles in CTRLs. Conversely, lower FDG_Cortex was associated with higher Qalb and higher plasma glucose levels within the AD group. Moreover, lower FDG_Ventricles and FDG_Ventricles/FDG_Cortex ratios were associated with elevated CSF lactates in this group. Stratifying AD patients by Apolipoprotein E (APOE) genotype revealed distinct patterns. In APOE ε3 homozygotes, FDG_Cortex showed no associations, while FDG_Ventricles and FDG_Ventricles/FDG_Cortex were negatively associated with CSF lactate. In APOE ε4 carriers, lower FDG_Cortex was linked to higher plasma glucose and QAlb, whereas FDG_Ventricles and FDG_Ventricles/FDG_Cortex were positively associated with CSF p-tau/Aβ42. Our findings suggest that, in patients with AD, FDG_Ventricles and the FDG_Ventricles/FDG_Cortex ratio may reflect alterations in brain metabolism and glucose extraction capacity. These parameters are differently linked with age, BBB integrity, and metabolic dysfunction (CSF lactates), according to APOE genotype. Full article

Sclerostin, encoded by the SOST gene, is a novel bone anabolic target for bone diseases. Humanized anti-sclerostin antibody, romosozumab, was approved for treatment of postmenopausal osteoporosis by the US Food and Drug Administration (FDA), but with a black-box warning on cardiovascular risk. The clinical data regarding cardiovascular events from various pre-marketing and post-marketing studies of romosozumab were inconsistent. Overall, the cardiovascular risk of sclerostin inhibition could not be excluded. The restriction of romosozumab in patients with cardiovascular disease history would be necessary. Moreover, genome-wide association study (GWAS) analyses of SOST variants revealed inconsistent results of the association between SOST variations and cardiovascular diseases. Further research incorporating larger sample sizes and functional analyses are necessary. In analyses of serum/tissue sclerostin levels in patients with cardiovascular diseases, the results were controversial but indicated an association between sclerostin and the presence/severity/outcomes of cardiovascular diseases. Nonclinical studies in rodents indicated the inhibitory effect of sclerostin on inflammation, aortic aneurysm, atherosclerosis, and vascular calcification. Sclerostin loop3 participated in the inhibitory effect of sclerostin on bone formation, while the cardiovascular protective effect of sclerostin was independent of sclerostin loop3. Macrophagic sclerostin loop2–apolipoprotein E receptor 2 (ApoER2) interaction participated in the inhibitory effect of sclerostin on inflammation in vitro. Sclerostin in human aortic smooth muscle cells participated in the reduction in calcium deposition. The role of sclerostin in cardiovascular system deserves further investigation. Full article