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Journal of Extracellular Biology Feb 2024Extracellular vesicles (EVs) are cell derived membranous nanoparticles. EVs are important mediators of cell-cell communication via the transfer of bioactive content and...
Extracellular vesicles (EVs) are cell derived membranous nanoparticles. EVs are important mediators of cell-cell communication via the transfer of bioactive content and as such they are being investigated for disease diagnostics as biomarkers and for potential therapeutic cargo delivery to recipient cells. However, existing methods for isolating EVs from biological samples suffer from challenges related to co-isolation of unwanted materials such as proteins, nucleic acids, and lipoproteins. In the pursuit of improved EV isolation techniques, we introduce multimodal flowthrough chromatography (MFC) as a scalable alternative to size exclusion chromatography (SEC). The use of MFC offers significant advantages for purifying EVs, resulting in enhanced yields and increased purity with respect to protein and nucleic acid co-isolates from conditioned 3D cell culture media. Compared to SEC, significantly higher EV yields with similar purity and preserved functionality were also obtained with MFC in 2D cell cultures. Additionally, MFC yielded EVs from serum with comparable purity to SEC and similar apolipoprotein B content. Overall, MFC presents an advancement in EV purification yielding EVs with high recovery, purity, and functionality, and offers an accessible improvement to researchers currently employing SEC.
PubMed: 38939900
DOI: 10.1002/jex2.138 -
Annals of Ibadan Postgraduate Medicine Apr 2024A major modifiable risk factor for atherosclerotic cardiovascular disease is abnormalities in lipid and lipoprotein metabolism which are frequently seen in HIV as well...
BACKGROUND AND OBJECTIVE
A major modifiable risk factor for atherosclerotic cardiovascular disease is abnormalities in lipid and lipoprotein metabolism which are frequently seen in HIV as well as its treatment. Apo-E is a protein that is important in plasma lipid homeostasis and its genetic alleles have been shown to contribute to lipid abnormalities. We examined for the effect of Apo-E gene polymorphisms on plasma lipid levels in PLHIV on protease inhibitor therapy.
METHODS
This was a cross-sectional study conducted among adult persons living with HIV. Lipid profile, Apo-B and Apo-A were measured in fasting plasma. Amplification and analysis of Apo-E genotypes were determined using the Seeplex Apo-E ACE genotyping kit. Differences in quantitative values were compared with non-parametric analysis methods.
RESULTS
Eighty-four persons were recruited into the study, 75% of whom were virally suppressed. The 3 homozygous genotypes had significantly different levels of low-density lipoprotein cholesterol (LDL-C), Apolipoprotein B (Apo-B) and Apolipoprotein A1 (Apo-A1). Persons with apo ε2/ε2 had higher LDL-C compared to those with apo ε3/ε3 (3.26 (3.61) mmol/L vs. 2.76 (1.28) mmol/L, p = 0.010). Those with apo ε4/ε4 had lower Apo-A1 compared to those with apo ε3/ε3 (0.84 (0.48) g/dL vs. 1.27 (0.70) g/dL, p =0.009). Compared with the same group, the heterozygous genotype, apo ε2/ε3 had lower triglyceride levels :1.33 (0.65) mmol/ L vs. 1.86 (1.11) mmol/L, p = 0.045.
CONCLUSION
Polymorphisms in the Apo-E gene may have significant influences on plasma lipid and apolipoprotein levels in PLHIV on PI therapy. This may have implications for the assessment of risk for cardiovascular disease.
PubMed: 38939889
DOI: No ID Found -
JACC. Advances Sep 2023In the SPARCL (Stroke Prevention by Aggressive Reduction in Cholesterol levels) trial, atorvastatin (80 mg/d) was compared to placebo in patients with recent stroke or...
BACKGROUND
In the SPARCL (Stroke Prevention by Aggressive Reduction in Cholesterol levels) trial, atorvastatin (80 mg/d) was compared to placebo in patients with recent stroke or transient ischemic attack (TIA) and no known coronary artery disease.
OBJECTIVES
This study aimed to assess the contribution of lipoprotein(a) [Lp(a)] to subsequent cerebrovascular and cardiovascular events in stroke/TIA survivors.
METHODS
Lp(a) levels and apolipoprotein(a) [apo(a)] isoform size were determined by liquid-chromatography mass spectrometry in samples collected at baseline from 2,814 SPARCL participants (1,418 randomized to atorvastatin and 1,396 to placebo). Within each treatment arm, patients in the highest quartile (≥84.0 nmol/L) were compared with those in the lowest quartiles of Lp(a) concentrations. Patients in the lowest quartile (≤25.9 Kringle IV domains) of apo(a) isoform sizes were compared with those in the highest quartiles. Multivariable-adjusted HRs were calculated using Cox proportional regression models.
RESULTS
There was no significant association between Lp(a) concentrations or apo(a) isoform sizes and the risk of recurrent stroke, the primary outcome of SPARCL, or cerebrovascular events in patients randomized to atorvastatin or placebo. In contrast, in patients randomized to atorvastatin, elevated Lp(a) concentrations and short apo(a) isoforms were positively and independently associated with an increased risk of coronary events (HR: 1.607 [95% CI: 1.007-2.563] and HR: 2.052 [95% CI: 1.303-3.232]). No such association was found in patients randomized to placebo (HR: 1.025 [95% CI: 0.675-1.555] and HR: 1.097 [95% CI: 0.735-1.637]).
CONCLUSIONS
Lp(a) contributes to the residual coronary artery disease risk of statin-treated stroke/TIA survivors, paving the way for use of therapies targeting Lp(a) in this population with stroke. (Lipitor In The Prevention Of Stroke, For Patients Who Have Had A Previous Stroke [SPARCL]; NCT00147602).
PubMed: 38939496
DOI: 10.1016/j.jacadv.2023.100557 -
JACC. Advances Feb 2024
PubMed: 38939384
DOI: 10.1016/j.jacadv.2023.100756 -
JACC. Advances Feb 2024The initiation of coronary artery calcium (CAC) is an important physiologic milestone associated with increased cardiovascular disease risk. However, traditional risk...
BACKGROUND
The initiation of coronary artery calcium (CAC) is an important physiologic milestone associated with increased cardiovascular disease risk. However, traditional risk factors (RF) do not perform well for predicting incident CAC among the 54 million older U.S. adults.
OBJECTIVES
The authors sought to assess the association between nontraditional cardiovascular disease RF and incident CAC in older persons.
METHODS
There were 815 MESA (Multi-Ethnic Study of Atherosclerosis) participants ≥65 years of age who had CAC = 0 at Visit 1 and a follow-up CAC scan. Multivariable adjusted Cox hazards ratios (aHR) and C-statistics were calculated to examine the association of nontraditional RF with incident CAC.
RESULTS
The mean age was 70.2 years and 67% were women. The median follow-up time to repeat CAC scan was 3.6 years (IQR: 2.6-9.2 years) and 45% of participants developed incident CAC. Albuminuria (aHR: 1.50, 95% CI: 1.07-2.09), carotid plaque (aHR: 1.32, 95% CI: 1.04-1.66), and thoracic aortic calcification (TAC) (aHR: 1.38, 95% CI: 1.10-1.75) were significantly associated with incident CAC, while higher levels of nontraditional RF including apolipoprotein-B, lipoprotein(a), high-sensitivity troponin T, and N-terminal pro-brain natriuretic peptide were not. When added to demographics, albuminuria, carotid plaque, and TAC provided a greater C-statistic improvement (+0.047, = 0.004) vs all traditional RF combined (+0.033, = 0.05).
CONCLUSIONS
Among nontraditional RF and measures of subclinical atherosclerosis, only albuminuria, carotid plaque, and TAC were significantly associated with incident CAC in persons ≥65 years of age. Identification of albuminuria or extracoronary atherosclerosis may help guide the timing of repeat CAC scoring in older persons with baseline CAC = 0.
PubMed: 38939371
DOI: 10.1016/j.jacadv.2023.100755 -
Frontiers in Aging Neuroscience 2024At least one-third of the identified risk alleles from Genome-Wide Association Studies (GWAS) of Alzheimer's disease (AD) are involved in lipid metabolism, lipid...
INTRODUCTION
At least one-third of the identified risk alleles from Genome-Wide Association Studies (GWAS) of Alzheimer's disease (AD) are involved in lipid metabolism, lipid transport, or direct lipid binding. In fact, a common genetic variant (ε4) in a cholesterol and phospholipid transporter, Apolipoprotein E (), is the primary genetic risk factor for late-onset AD. In addition to genetic variants, lipidomic studies have reported severe metabolic dysregulation in human autopsy brain tissue, cerebrospinal fluid, blood, and multiple mouse models of AD.
METHODS
We aimed to identify an overarching metabolic pathway in lipid metabolism by integrating analyses of lipidomics and transcriptomics from the Religious Order Study and Rush Memory Aging Project (ROSMAP) using differential analysis and network correlation analysis.
RESULTS
Coordinated differences in lipids were found to be dysregulated in association with both mild cognitive impairment (MCI) and carriers. Interestingly, these correlations were weakened when adjusting for education. Indeed, the cognitively non-impaired carriers have higher education levels in the ROSMAP cohort, suggesting that this lipid signature may be associated with a resilience phenotype. Network correlation analysis identified multiple differential lipids within a single module that are substrates and products in the Lands Cycle for acyl chain remodeling. In addition, our analyses identified multiple genes in the Lands Cycle acyl chain remodeling pathway, which were associated with cognitive decline independent of amyloid-β (Aβ) load and tau tangle pathologies.
DISCUSSION
Our studies highlight the critical differences in acyl chain remodeling in brain tissue from carriers and individual non-carriers with MCI. A coordinated lipid profile shift in dorsolateral prefrontal cortex from both carriers and MCI suggests differences in lipid metabolism occur early in disease stage and highlights lipid homeostasis as a tractable target for early disease modifying intervention.
PubMed: 38938596
DOI: 10.3389/fnagi.2024.1419253 -
Frontiers in Endocrinology 2024The existing research on the association between apolipoproteins (Apos) and erectile dysfunction (ED) primarily relies on observational studies and does not distinguish...
The existing research on the association between apolipoproteins (Apos) and erectile dysfunction (ED) primarily relies on observational studies and does not distinguish between organic and psychogenic causes when diagnosing ED. It is difficult to believe that Apos play a role in psychogenic ED. To address these issues, our study explored the causal relationship between lipoproteins and ED using Mendelian randomization (MR) analysis and differentiate between organic and psychogenic ED through the use of nocturnal penile tumescence and rigidity (NPTR) monitoring. Multivariate MR analysis revealed significant causal associations between high-density lipoprotein (HDL), Apo A1, and Apo B/A1 with ED (OR and 95% CI were 0.33 (0.14-0.78), 3.58 (1.52-8.43), and 0.30 (0.13-0.66)). we conducted statistical and analytical analyses on the data of 212 patients using multivariate analyses and receiver operating characteristic (ROC) curves. Patients with organic ED had significantly lower levels of HDL, Apo A1 and Apo A1/B, whereas patients with organic ED had considerably higher levels of Apo B and low-density lipoprotein (LDL). The diagnostic value of Apos in predicting the risk of organic ED was evaluated using ROC curves. The results indicated that Apo A1 and Apo A1/B demonstrated good predictive value. HDL, Apo A1, and Apo A1/B have been identified as risk factors for ED in our study. Furthermore, our research highlights the significance of Apo A1 and Apo A1/Apo B in the development of organic ED and suggests their potential use as indicators to assess the risks associated with organic ED.
Topics: Humans; Male; Mendelian Randomization Analysis; Erectile Dysfunction; Case-Control Studies; Middle Aged; Apolipoproteins; Adult; Apolipoprotein A-I; Lipoproteins, HDL
PubMed: 38938512
DOI: 10.3389/fendo.2024.1359015 -
Scientific Reports Jun 2024A rise in bone turnover markers (BTM) after bariatric surgery predicts poor bone health years later. This study explored factors associated with BTM and changes in BTM...
A rise in bone turnover markers (BTM) after bariatric surgery predicts poor bone health years later. This study explored factors associated with BTM and changes in BTM after bariatric surgery. Inclusion criteria were subjects 18 to 65 years of age with morbid obesity undergoing bariatric surgery. All data were measured before and 6 and 12 months after surgery. The study included 104 subjects: women/men: 83/21; mean age 43.1 (SD 8.4) years; BMI: 38.8 kg/m (SD 3.8). Surgery with Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) was performed in 84 (81%) and 20 (19%) subjects, respectively. From before to 6-12 months after surgery, procollagen type 1 N-terminal propeptid (P1NP) increased by 45.6 µg/L (95% CI 41.5-50.0, p < 0.001), and alkaline phosphatase (ALP) by 10 U/L (95% CI 7-14, p < 0.001). The increases were significantly larger after RYGB than after SG. The APOE- Ɛ3 allele was associated with low levels of BTM and high levels of leptin. There was an unfavourable increase in BTM after bariatric surgery. SG compared to RYGB and the presence of the APOE-Ɛ3 allele were associated with less unfavourable effects. The study emphasises the importance of optimal prophylactic interventions after bariatric surgery to prevent osteoporosis.
Topics: Humans; Female; Male; Adult; Middle Aged; Bone Remodeling; Biomarkers; Bariatric Surgery; Obesity, Morbid; Peptide Fragments; Procollagen; Gastrectomy; Gastric Bypass; Alkaline Phosphatase; Leptin; Aged; Adolescent
PubMed: 38937532
DOI: 10.1038/s41598-024-65952-y -
Pharmaceutical Research Jun 2024Individuals with Alzheimer's disease (AD) often require many medications; however, these medications are dosed using regimens recommended for individuals without AD....
BACKGROUND
Individuals with Alzheimer's disease (AD) often require many medications; however, these medications are dosed using regimens recommended for individuals without AD. This is despite reduced abundance and function of P-glycoprotein (P-gp) at the blood-brain barrier (BBB) in AD, which can impact brain exposure of drugs. The fundamental mechanisms leading to reduced P-gp abundance in sporadic AD remain unknown; however, it is known that the apolipoprotein E (apoE) gene has the strongest genetic link to sporadic AD development, and apoE isoforms can differentially alter BBB function. The aim of this study was to assess if apoE affects P-gp abundance and function in an isoform-dependent manner using a human cerebral microvascular endothelial cell (hCMEC/D3) model.
METHODS
This study assessed the impact of apoE isoforms on P-gp abundance (by western blot) and function (by rhodamine 123 (R123) uptake) in hCMEC/D3 cells. Cells were exposed to recombinant apoE3 and apoE4 at 2 - 10 µg/mL over 24 - 72 hours. hCMEC/D3 cells were also exposed for 72 hours to astrocyte-conditioned media (ACM) from astrocytes expressing humanised apoE isoforms.
RESULTS
P-gp abundance in hCMEC/D3 cells was not altered by recombinant apoE4 relative to recombinant apoE3, nor did ACM containing human apoE isoforms alter P-gp abundance. R123 accumulation in hCMEC/D3 cells was also unchanged with recombinant apoE isoform treatments, suggesting no change to P-gp function, despite both abundance and function being altered by positive controls SR12813 (5 µM) and PSC 833 (5 µM), respectively.
CONCLUSIONS
Different apoE isoforms have no direct influence on P-gp abundance or function within this model, and further in vivo studies would be required to address whether P-gp abundance or function are reduced in sporadic AD in an apoE isoform-specific manner.
PubMed: 38937373
DOI: 10.1007/s11095-024-03731-0 -
Immunobiology Jun 2024As metastatic papillary thyroid carcinoma becomes increasingly challenging to treat, immunotherapy has emerged as a new research direction. Tumor-associated macrophages...
BACKGROUND
As metastatic papillary thyroid carcinoma becomes increasingly challenging to treat, immunotherapy has emerged as a new research direction. Tumor-associated macrophages (TAMs) influence the occurrence, invasion, and metastasis of tumors. Apolipoprotein E (APOE) can regulate the polarization changes of macrophages and participate in the remodeling of the tumor microenvironment. However, the role of APOE in regulating the polarization and biological functions of TAMs in papillary thyroid carcinoma (PTC) remains unclear, as it acts as a dual biomarker.
METHODS
We probed APOE expression in PTC tissues using immunohistochemical staining. A cell co-culture model was established where different APOE-expressing K1 cells were co-cultured with THP-1-derived M0 macrophages. An in-depth analysis of macrophage polarization behavior was performed using real-time quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and western blotting. Subsequently, the impact of APOE-regulated macrophages on tumor cell behavior, especially proliferation, migration, and invasion, was evaluated utilizing IncuCyte ZOOM system, flow cytometry, colony formation, and scratch experiments. Finally, we used a xenograft model to confirm the effects of APOE on PTC tumorigenesis.
RESULTS
Tumor dimensions, stage, and lymphatic metastases were significantly associated with increased APOE expression in PTC tissues. K1 cells were markedly limited in their proliferation, migration, and invasion abilities when APOE expression was silenced, a process mediated by the PI3K/Akt/NF-κB signaling axis. Moreover, APOE is a key facilitator of the enhancement of the anti-inflammatory cytokines IL-10 and TGF-β1. In PTC cellular models, APOE contributed to the phenotypic shift of THP-1 derived macrophages towards an M2 phenotypic polarization, predominantly through the modulation of IL-10. Furthermore, in vivo studies involving athymic nude mice have demonstrated pivotal role of APOE in tumor progression and the induction of M2-like TAM polarization.
CONCLUSION
Our results elucidated that APOE could promote the shift of TAMs from M0-type to M2-type polarization by regulating inflammatory factors expressions in K1 cell through the PI3K/Akt/NF-κB pathway. These findings are crucial for understanding the molecular mechanisms underlying PTC pathogenesis and for developing immunological drugs to treat this disease.
PubMed: 38935988
DOI: 10.1016/j.imbio.2024.152821