The Impact of Metabolic and Bariatric Surgery on Apo B100 Levels in Individuals with high BMI: A Multi-Centric Prospective Cohort Study.

BACKGROUND: Metabolic and Bariatric surgery (MBS) leads to significant weight loss and improvements in obesity-related comorbidities. However, the impact of MBS on Apolipoprotein B100 (Apo-B100) regulation is unclear. Apo-B100 is essential for the assembly and secretion of serum lipoprotein particles. Elevated levels of these factors can accelerate the development of atherosclerotic plaques in blood vessels. This study aimed to evaluate changes in Apo-B100 levels following MBS. METHODS: 121 participants from the Iranian National Obesity and Metabolic Surgery Database (INOSD) underwent Laparoscopic Sleeve Gastrectomy (LSG) (n = 43), One-Anastomosis Gastric Bypass (OAGB) (n = 70) or Roux-en-Y Gastric Bypass (RYGB) (n = 8). Serum Apo-B100, lipid profiles, liver enzymes, and fasting glucose were measured preoperatively and six months postoperatively. RESULTS: Apo-B100 levels significantly decreased from 94.63 ± 14.35 mg/dL preoperatively to 62.97 ± 19.97 mg/dL after six months (p < 0.01), alongside reductions in total cholesterol, triglycerides, LDL, VLDL, AST, and ALT (p < 0.05). Greater Apo-B100 reductions occurred in non-diabetics versus people with diabetes (p = 0.012) and strongly correlated with baseline Apo-B100 (r = 0.455, p < 0.01) and LDL levels (r = 0.413, p < 0.01). However, surgery type did not impact Apo-B100 changes in multivariate analysis (p > 0.05). CONCLUSION: Bariatric surgery leads to a significant reduction in Apo-B100 levels and improvements in lipid profiles and liver enzymes, indicating a positive impact on dyslipidemia and cardiovascular risk in individuals with high BMI.

Anti-Lipoprotein Lipase Antibody as a Useful Marker for Plaque Vulnerability in Patients with Stable Angina.

AIMS: Identifying patients with vulnerable plaque who have poor prognosis among those with coronary artery disease (CAD) is crucial to deciding future therapeutic interventions. We previously reported that male CAD patients with low anti-apolipoprotein B-100 autoantibody (anti-apoB-100 Ab) levels were at an increased risk of developing unstable plaque lesions. This study focused on the autoantibodies against lipoprotein lipase (LPL), a key enzyme in triglyceride metabolism, which is another risk factor for atherosclerosis, and investigated their association with plaque characteristics. METHODS: We measured serum anti-LPL Ab levels using a homemade enzyme-linked immunosorbent assay in 80 male CAD patients. Coronary plaque properties were evaluated using iMAP®-intravascular ultrasound. RESULTS: Serum anti-LPL Ab levels were not correlated with plaque burden but were significantly negatively and positively correlated with fibrotic and necrotic plaques, respectively. High-risk patients with low anti-apoB-100 Ab levels were divided into groups according to their anti-LPL Ab levels. The group with high anti-LPL Ab levels exhibited more necrotic plaques and fewer fibrotic plaques as well as higher remnant-like lipoprotein particle levels than the group with low anti-LPL Ab levels. CONCLUSIONS: Serum anti-LPL Ab levels can serve as a marker of plaque instability in CAD patients and can help identify higher-risk cases when combined with anti-apoB-100 Ab levels.

Stent composition and immune response after long-term coronary angioplasty.

Background: There are limited data about the influence of stent composition on immune responses after percutaneous coronary intervention (PCI). Objective: The aim was to compare the effects of PCI with conventional cobalt-chromium bare metal stent (BMS) and drug-eluting stent (DES) implantation on the modulation of humoral and cellular immune responses. Methods: A randomised, single-centre, open pilot study involving patients with stable coronary artery disease eligible for PCI was performed. Blood samples were collected from the peripheral artery (PA) and the coronary sinus (CS) at baseline and 40 weeks following PCI. IgM and IgG autoantibodies (Abs), anti-oxLDL and anti-ApoB-D, as well as cytokine levels were evaluated by enzyme-linked immunosorbent assay. Results: A total of 30 patients of 60 years mean age were included, 68% of whom were men. At the nine-month follow-up, a modulation in the levels of cytokines and autoantibodies was observed in both stent type groups. However, no difference was observed in the modulation of these markers between stents. Conclusion: The stent type promotes modulations in cellular and humoral immune responses in the long-term, with differences in the magnitude of effects in specific immune responses.

Contribution of intestinal triglyceride-rich lipoproteins to residual atherosclerotic cardiovascular disease risk in individuals with type 2 diabetes on statin therapy.

AIMS/HYPOTHESIS: This study explored the hypothesis that significant abnormalities in the metabolism of intestinally derived lipoproteins are present in individuals with type 2 diabetes on statin therapy. These abnormalities may contribute to residual CVD risk. METHODS: To investigate the kinetics of ApoB-48- and ApoB-100-containing lipoproteins, we performed a secondary analysis of 11 overweight/obese individuals with type 2 diabetes who were treated with lifestyle counselling and on a stable dose of metformin who were from an earlier clinical study, and compared these with 11 control participants frequency-matched for age, BMI and sex. Participants in both groups were on a similar statin regimen during the study. Stable isotope tracers were used to determine the kinetics of the following in response to a standard fat-rich meal: (1) apolipoprotein (Apo)B-48 in chylomicrons and VLDL; (2) ApoB-100 in VLDL, intermediate-density lipoprotein (IDL) and LDL; and (3) triglyceride (TG) in VLDL. RESULTS: The fasting lipid profile did not differ significantly between the two groups. Compared with control participants, in individuals with type 2 diabetes, chylomicron TG and ApoB-48 levels exhibited an approximately twofold higher response to the fat-rich meal, and a twofold higher increment was observed in ApoB-48 particles in the VLDL1 and VLDL2 density ranges (all p < 0.05). Again comparing control participants with individuals with type 2 diabetes, in the latter, total ApoB-48 production was 25% higher (556 ± 57 vs 446 ± 57 mg/day; p < 0.001), conversion (fractional transfer rate) of chylomicrons to VLDL was around 40% lower (35 ± 25 vs 82 ± 58 pools/day; p=0.034) and direct clearance of chylomicrons was 5.6-fold higher (5.6 ± 2.2 vs 1.0 ± 1.8 pools/day; p < 0.001). During the postprandial period, ApoB-48 particles accounted for a higher proportion of total VLDL in individuals with type 2 diabetes (44%) compared with control participants (25%), and these ApoB-48 VLDL particles exhibited a fivefold longer residence time in the circulation (p < 0.01). No between-group differences were seen in the kinetics of ApoB-100 and TG in VLDL, or in LDL ApoB-100 production, pool size and clearance rate. As compared with control participants, the IDL ApoB-100 pool in individuals with type 2 diabetes was higher due to increased conversion from VLDL2. CONCLUSIONS/INTERPRETATION: Abnormalities in the metabolism of intestinally derived ApoB-48-containing lipoproteins in individuals with type 2 diabetes on statins may help to explain the residual risk of CVD and may be suitable targets for interventions. TRIAL REGISTRATION: ClinicalTrials.gov NCT02948777.

Targeting structural flexibility in low density lipoprotein by integrating cryo-electron microscopy and high-speed atomic force microscopy.

Low-density lipoprotein (LDL) plays a crucial role in cholesterol metabolism. Responsible for cholesterol transport from the liver to the organs, LDL accumulation in the arteries is a primary cause of cardiovascular diseases, such as atherosclerosis. This work focuses on the fundamental question of the LDL molecular structure, as well as the topology and molecular motions of apolipoprotein B-100 (apo B-100), which is addressed by single-particle cryo-electron microscopy (cryo-EM) and high-speed atomic force microscopy (HS-AFM). Our results suggest a revised model of the LDL core organization with respect to the cholesterol ester (CE) arrangement. In addition, a high-density region close to the flattened poles could be identified, likely enriched in free cholesterol. The most remarkable new details are two protrusions on the LDL surface, attributed to the protein apo B-100. HS-AFM adds the dimension of time and reveals for the first time a highly dynamic direct description of LDL, where we could follow large domain fluctuations of the protrusions in real time. To tackle the inherent flexibility and heterogeneity of LDL, the cryo-EM maps are further assessed by 3D variability analysis. Our study gives a detailed explanation how to approach the intrinsic flexibility of a complex system comprising lipids and protein.

Role of interleukin-6 and interleukin-10 in morphological and functional changes of the blood-brain barrier in hypertriglyceridemia.

BACKGROUND: Hypertriglyceridemia is closely linked to atherosclerosis related inflammatory processes and blood-brain barrier (BBB) dysfunction. Using apolipoprotein B-100 (APOB-100) transgenic mice, an animal model of chronic hypertriglyceridemia, we analyzed BBB function and morphology in vitro and ex vivo. Our objective was to determine which BBB characteristics are produced mainly by interleukin (IL)-6, an atherosclerosis promoting cytokine, and whether these actions can be antagonized by IL-10, an anti-inflammatory cytokine. METHODS: Brain endothelial and glial cell cultures and brain microvessels were isolated from wild type (WT) and APOB-100 transgenic mice and were treated with IL-6, IL-10 and their combination. First, IL-6 and IL-10 production was measured in WT and APOB-100 microvessels using qPCR. Then functional parameters of endothelial cell cultures were analyzed and immunocytochemistry for key BBB proteins was performed. RESULTS: IL-6 mRNA levels were higher in brain microvessels than in brain parenchyma of APOB-100 transgenic mice. Transendothelial electric resistance and P-glycoprotein activity were lower, and paracellular permeability was higher in cultured APOB-100 brain endothelial cells. These features were sensitive to both IL-6 and IL-10 treatments. A decreased P-glycoprotein immunostaining was measured in transgenic endothelial cells under control conditions and in WT cells after treating them with IL-6. This effect was antagonized by IL-10. Changes in immunostaining for tight junction proteins were observed after IL-6 exposure, which were in part antagonized by IL-10. In glial cell cultures an increase in aquaporin-4 immunolabeling in the transgenic group and an increase in microglia cell density in WT glia cultures was detected after IL-6 treatment, which was antagonized by IL-10. In isolated brain microvessels a decrease in P-glycoprotein immunolabeled area fraction was measured in APOB-100 microvessels under control conditions and in WT microvessels after every cytokine treatment. ZO-1 immunolabeling showed characteristics similar to that of P-glycoprotein. No change was seen in claudin-5 and occludin immunoreactive area fractions in microvessels. A decrease in aquaporin-4 immunoreactivity was measured in WT microvessels treated by IL-6, which was antagonized by IL-10. CONCLUSION: IL-6 produced in microvessels contributes to BBB impairment observed in the APOB-100 mice. We showed that IL-10 partly antagonizes the effects of IL-6 at the BBB.

A New Structural Model of Apolipoprotein B100 Based on Computational Modeling and Cross Linking.

ApoB-100 is a member of a large lipid transfer protein superfamily and is one of the main apolipoproteins found on low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) particles. Despite its clinical significance for the development of cardiovascular disease, there is limited information on apoB-100 structure. We have developed a novel method based on the "divide and conquer" algorithm, using PSIPRED software, by dividing apoB-100 into five subunits and 11 domains. Models of each domain were prepared using I-TASSER, DEMO, RoseTTAFold, Phyre2, and MODELLER. Subsequently, we used disuccinimidyl sulfoxide (DSSO), a new mass spectrometry cleavable cross-linker, and the known position of disulfide bonds to experimentally validate each model. We obtained 65 unique DSSO cross-links, of which 87.5% were within a 26 Å threshold in the final model. We also evaluated the positions of cysteine residues involved in the eight known disulfide bonds in apoB-100, and each pair was measured within the expected 5.6 Å constraint. Finally, multiple domains were combined by applying constraints based on detected long-range DSSO cross-links to generate five subunits, which were subsequently merged to achieve an uninterrupted architecture for apoB-100 around a lipoprotein particle. Moreover, the dynamics of apoB-100 during particle size transitions was examined by comparing VLDL and LDL computational models and using experimental cross-linking data. In addition, the proposed model of receptor ligand binding of apoB-100 provides new insights into some of its functions.

Apolipoprotein B-100-mediated motor neuron degeneration in sporadic amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis is a fatal neurodegenerative disease characterized by motor neuron degeneration. Approximately 90% of cases occur sporadically with no known cause while 10% are familial cases arising from known inherited genetic mutations. In vivo studies have predominantly utilized transgenic models harbouring amyotrophic lateral sclerosis-associated gene mutations, which have not hitherto elucidated mechanisms underlying motor neuron death or identified therapeutic targets specific to sporadic amyotrophic lateral sclerosis. Here we provide evidence demonstrating pathogenic differences in CSF from patients with sporadic amyotrophic lateral sclerosis and familial amyotrophic lateral sclerosis patients with mutations in SOD1, C9orf72 and TARDBP. Using a novel CSF-mediated animal model, we show that intrathecal delivery of sporadic amyotrophic lateral sclerosis patient-derived CSF into the cervical subarachnoid space in adult wild-type mice induces permanent motor disability which is associated with hallmark pathological features of amyotrophic lateral sclerosis including motor neuron loss, cytoplasmic TDP-43 translocation, reactive astrogliosis and microglial activation. Motor impairments are not induced by SOD1, C9orf72 or TARDBP CSF, although a moderate degree of histopathological change occurs in C9orf72 and TARDBP CSF-injected mice. By conducting a series of CSF filtration studies and global proteomic analysis of CSF, we identified apolipoprotein B-100 in sporadic amyotrophic lateral sclerosis CSF as the putative agent responsible for inducing motor disability, motor neuron degeneration and pathological translocation of TDP-43. Apolipoprotein B-100 alone is sufficient to recapitulate clinical and pathological outcomes in vivo and induce death of human induced pluripotent stem cell-derived motor neurons in vitro. Targeted removal of apolipoprotein B-100 from sporadic amyotrophic lateral sclerosis CSF via filtration or immunodepletion successfully attenuated the neurotoxic capacity of sporadic amyotrophic lateral sclerosis CSF to induce motor disability, motor neuron death, and TDP-43 translocation. This study presents apolipoprotein B-100 as a novel therapeutic target specific for the predominant sporadic form of amyotrophic lateral sclerosis and establishes proof-of-concept to support CSF pheresis as a therapeutic strategy for mitigating neurotoxicity in sporadic amyotrophic lateral sclerosis.

Familial Hypercholesterolemia: Real-World Data of 1236 Patients Attending a Czech Lipid Clinic. A Retrospective Analysis of Experience in More than 50 years. Part I: Genetics and Biochemical Parameters.

Introduction: The cause of familial hypercholesterolemia (FH) is defect in LDL receptor or familial defect of apolipoprotein B-100 (FDB) or, rarely, defect in proprotein convertase subtilisin/kexin type 9. Identification and treatment of patients with FH improves their prognosis. Our data represent retrospective analysis of 50 years of specialised care in our center. Patients and Methods: A group of 1236 FH patients (841 women, 395 men; 993 study subjects and 243 relatives; mean age 44.8 ± 16.7 years) included 154 FDB patients followed at the Lipid Clinic of the General University Hospital in Prague since the mid-1960s to the present. Clinical diagnosis was based on the Dutch Lipid Clinic Network Criteria. Genetic analysis was performed using PCR-RFLP to detect FDB and apolipoprotein E (APOE) polymorphism. Biochemical data were collected and statistically analysed. Results: At baseline, mean LDL-C and total cholesterol (TC) levels of all FH patients combined were 6.49 ± 1.92 mmol/L and 8.95 ± 1.95 mmol/L, respectively. Their LDL-C levels decreased to 3.26 ± 1.57 mmol/L and TC levels to 5.43 ± 1.69 mmol/L during follow-up. In the subgroup of LDL receptor-mediated FH (non-FDB) patients, baseline LDL-C and TC levels of 6.61 ± 1.95 mmol/L and 9.09 ± 1.97 mmol/L declined to 3.21 ± 1.60 mmol/L and 5.39 ± 1.72 mmol/L, respectively, during follow-up. In the FDB subgroup of patients, baseline levels of LDL-C and TC were 5.57 ± 1.46 mmol/L and 7.88 ± 1.58 mmol/L decreasing to 3.45 ± 0.24 mmol/L and 5.58 ± 1.37 mmol/L, respectively, during follow-up. Differences were also found in the effects of various APOE isoforms on lipid lowering. A significant decrease in lipid parameters was observed with the E2E2 isoform whereas a minimal decrease was seen with the E4E4 and E3E3 isoforms. Conclusion: Whereas, overall, non-FDB patients had higher baseline lipid levels, these levels declined more appreciably compared with FDB patients during follow-up. Our retrospective analysis also found different effects of APOE isoforms on the decrease in lipid levels.

Quantifying the contribution of lipoprotein(a) to all apoB containing particles.

BACKGROUND: Elevated lipoprotein (a) [Lp(a)] is an independent risk factor for atherosclerotic cardiovascular disease (ASCVD). As clinical LDL cholesterol [LDL-C] incorporates cholesterol from Lp(a) [Lp(a)-C], there is interest in quantifying the contribution of Lp(a)-C to LDL-C given implications for risk assessment, diagnosis, and treatment. Estimating Lp(a)-C is subject to inaccuracies; measuring Lp(a) particle number [Lp(a)-P] is more accurate. OBJECTIVE: To capture how Lp(a) contributes to the concentration of atherogenic particles, we demonstrate a particle-based approach using readily available measures of Lp(a)-P and apolipoprotein B (apoB). METHODS: Using the Very Large Database of Lipids (VLDbL), we compared Lp(a)-P (nmol/L) with all apoB containing particles ("apoB-P"). apoB-P was calculated by converting apoB mass to molar concentration using the preserved molecular weight of apoB100 (512 kg/mol). We calculated the percentage of Lp(a)-P relative to apoB-P by Lp(a)-P deciles and stratified by triglycerides, LDL-C, and non-HDL-C. RESULTS: 158,260 patients from the VLDbL were included. The fraction Lp(a)-P/apoB-P increased with rising Lp(a)-P. Lp(a)-P comprised on average 3% of apoB containing particles among the study population and 15% at the highest Lp(a)-P decile. Lp(a)-P/apoB-P decreased at higher levels of triglycerides and LDL-C owing to larger contributions from VLDL and LDL. CONCLUSIONS: We demonstrate a particle-based approach to quantify the contribution of Lp(a) to all apoB-containing particles using validated and widely available clinical assays. This approach keeps in line with recommendations to move away from mass-based measurements of Lp(a) and prioritize more accurate particle-based measurements. Future research applying this method could define clinically meaningful thresholds and inform use in risk assessment and management.

Lipoprotein(a): A Genetically Determined, Causal, and Prevalent Risk Factor for Atherosclerotic Cardiovascular Disease: A Scientific Statement From the American Heart Association.

High levels of lipoprotein(a) [Lp(a)], an apoB100-containing lipoprotein, are an independent and causal risk factor for atherosclerotic cardiovascular diseases through mechanisms associated with increased atherogenesis, inflammation, and thrombosis. Lp(a) is predominantly a monogenic cardiovascular risk determinant, with ≈70% to ≥90% of interindividual heterogeneity in levels being genetically determined. The 2 major protein components of Lp(a) particles are apoB100 and apolipoprotein(a). Lp(a) remains a risk factor for cardiovascular disease development even in the setting of effective reduction of plasma low-density lipoprotein cholesterol and apoB100. Despite its demonstrated contribution to atherosclerotic cardiovascular disease burden, we presently lack standardization and harmonization of assays, universal guidelines for diagnosing and providing risk assessment, and targeted treatments to lower Lp(a). There is a clinical need to understand the genetic and biological basis for variation in Lp(a) levels and its relationship to disease in different ancestry groups. This scientific statement capitalizes on the expertise of a diverse basic science and clinical workgroup to highlight the history, biology, pathophysiology, and emerging clinical evidence in the Lp(a) field. Herein, we address key knowledge gaps and future directions required to mitigate the atherosclerotic cardiovascular disease risk attributable to elevated Lp(a) levels.

Polygenic architecture and cardiovascular risk of familial combined hyperlipidemia.

BACKGROUND AND AIMS: Familial combined hyperlipidemia (FCHL) is one of the most common inherited lipid phenotypes, characterized by elevated plasma concentrations of apolipoprotein B-100 and triglycerides. The genetic inheritance of FCHL remains poorly understood. The goals of this study were to investigate the polygenetic architecture and cardiovascular risk associated with FCHL. METHODS AND RESULTS: We identified individuals with an FCHL phenotype among 349,222 unrelated participants of European ancestry in the UK Biobank using modified versions of 5 different diagnostic criteria. The prevalence of the FCHL phenotype was 11.44% (n = 39,961), 5.01% (n = 17,485), 1.48% (n = 5,153), 1.10% (n = 3,838), and 0.48% (n = 1,688) according to modified versions of the Consensus Conference, Dutch, Mexico, Brunzell, and Goldstein criteria, respectively. We performed discovery, case-control genome-wide association studies for these different FCHL criteria and identified 175 independent loci associated with FCHL at genome-wide significance. We investigated the association of genetic and clinical risk with FCHL and found that polygenic susceptibility to hypercholesterolemia or hypertriglyceridemia and features of metabolic syndrome were associated with greater prevalence of FCHL. Participants with an FCHL phenotype had a similar risk of incident coronary artery disease compared to participants with monogenic familial hypercholesterolemia (adjusted hazard ratio vs controls [95% confidence interval]: 2.72 [2.31-3.21] and 1.90 [1.30-2.78]). CONCLUSIONS: These results suggest that, rather than being a single genetic entity, the FCHL phenotype represents a polygenic susceptibility to dyslipidemia in combination with metabolic abnormalities. The cardiovascular risk associated with an FCHL phenotype is similar to that of monogenic familial hypercholesterolemia, despite being ∼5x more common.

Biomarkers and Dynamic Cerebral Autoregulation of Obstructive Sleep Apnea-Hypopnea Syndrome.

OBJECTIVE: Patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) have impaired dynamic cerebral autoregulation (dCA). This study aimed to explore whether serum levels of apolipoprotein B-100 (ApoB-100), fibronectin (FN), and ceruloplasmin (CP) were related to impaired dCA in OSAHS. METHODS: A total of 90 patients with OSAHS from our database management system were enrolled and further divided into three subgroups according to the apnea-hypopnea index (AHI) using polysomnography results: mild (5 ≤ AHI ≤ 15), moderate (15 < AHI ≤ 30), and severe OSAHS (AHI > 30), with 30 patients in each group. Thirty sex- and age-matched healthy controls were recruited for this study. The serum levels of ApoB-100, FN, and CP were measured by enzyme-linked immunosorbent assays. dCA was assessed by analyzing the phase difference (PD) using transfer function analysis. RESULTS: Serum levels of ApoB-100, FN, and CP were significantly higher in the mild, moderate, and severe OSAHS groups than that in the control group (P<0.001, respectively). The average PD of the moderate and severe OSAHS groups was lower than that of the control group (P=0.001 and P<0.001, respectively). Receiver operating curve analysis revealed that ApoB-100, FN, and CP might be able to distinguish patients with OSAHS from healthy individuals (area under the curve = 0.959 [95% CI 0.92-1.00], 0.987 [95% CI 0.96-1.01], 0.982 [95% CI 0.96-1.00]), respectively, P<0.001). The average PD was linearly correlated with the serum levels of ApoB-100, FN, and CP in patients with OSAHS. Multivariable analysis showed that FN and arousal index in polysomnography were associated with impaired average PD (P<0.001 and P=0.025, respectively). CONCLUSION: Serum levels of ApoB-100, FN, and CP increased in patients with OSAHS. dCA was compromised in patients with OSAHS and was positively correlated with ApoB-100, FN, and CP serum levels, and FN serum levels and arousal index in polysomnography were independently associated with impaired dCA.

Two apolipoproteins in salmon louse (Lepeophtheirus salmonis), apolipoprotein 1 knock down reduces reproductive capacity.

The salmon louse, Lepeophtheirus salmonis is an ectoparasite of salmonid fish in the Northern Hemisphere, causing large economical losses in the aquaculture industry and represent a threat to wild populations of salmonids. Like other oviparous animals, it is likely that female lice use lipoproteins for lipid transport to maturing oocytes and other organs of the body. As an important component of lipoproteins, apolipoproteins play a vital role in the transport of lipids through biosynthesis of lipoproteins. Apolipoproteins have been studied in detail in different organisms, but no studies have been done in salmon lice. Two apolipoprotein encoding genes (LsLp1 and LsLp2) were identified in the salmon lice genome. Transcriptional analysis revealed both genes to be expressed at all stages from larvae to adult with some variation, LsLp1 generally higher than LsLp2 and both at their highest levels in adult stages of the louse. In adult female louse, the LsLp1 and LsLp2 transcripts were found in the sub-epidermal tissue and the intestine. RNA interference-mediated knockdown of LsLp1 and LsLp2 in female lice resulted in reduced expression of both transcripts. LsLp1 knockdown female lice produced significantly less offspring than control lice, while knockdown of LsLp2 in female lice caused no reduction in the number of offspring. These results suggest that LsLp1 has an important role in reproduction in female salmon lice.

Postprandial dyslipidemia after a standardized high-fat meal in BMI-matched healthy individuals, and in subjects with prediabetes or type 2 diabetes.

BACKGROUND & AIMS: A relationship between postprandial hyperlipidemia and glucose homeostasis/cardiovascular diseases has been suggested. We investigated postprandial plasma lipid patterns after a standardized high-fat meal and their association with glucose homeostasis and subclinical atherosclerosis. METHODS: Using matching by BMI, 32 healthy individuals with normal glucose tolerance (NGT), 21 subjects with impaired glucose tolerance (IGT), and 20 subjects with drug-naïve type 2 diabetes (T2D) were enrolled. Plasma concentrations of triglycerides (TGs), apolipoprotein-B (ApoB), ApoB48, ApoB100, glucose, and insulin at baseline and 1, 2, 3, 4, 5, 6, and 8 h after a standardized meal (1041.03 kcal with 70.99 g of fat) were measured. Body composition, abdominal visceral fat area, and resting energy expenditure (REE) were measured using dual energy X-ray absorptiometry, computed tomography, and indirect calorimetry, respectively. The intima-media thickness (IMT) of the carotid artery and the ankle-brachial index (ABI) were used to detect subclinical atherosclerosis. RESULTS: Baseline data and area under the curve (AUC) of plasma concentrations of TGs, ApoB, and ApoB48 in the IGT and T2D groups were higher than in the NGT group. The peak TG concentrations after the meal was observed at 5 h in subjects with IGT and T2D, while healthy subjects showed the highest concentrations at 4 h. In multivariable analysis, high abdominal visceral fat area and low HDL-cholesterol concentrations were independently associated with the AUCTG and AUCApoB after adjusting for confounders including baseline TG and the REE. High LDL-cholesterol and high HbA1c concentrations were also associated with the AUCApoB. Furthermore, high AUCTG and AUCApoB values were independent factors for an increased carotid IMT and a low ABI after adjusting for relevant variables. CONCLUSIONS: Abdominal visceral obesity and low HDL-cholesterol concentrations were associated with increased post load excursions of TGs and ApoB in this series. These elevated concentrations of TGs and ApoB were linked with subclinical atherosclerosis.

Assessing Genetic Overlap and Causality Between Blood Plasma Proteins and Alzheimer's Disease.

BACKGROUND: Blood plasma proteins have been associated with Alzheimer's disease (AD), but understanding which proteins are on the causal pathway remains challenging. OBJECTIVE: Investigate the genetic overlap between candidate proteins and AD using polygenic risk scores (PRS) and interrogate their causal relationship using bi-directional Mendelian randomization (MR). METHODS: Following a literature review, 31 proteins were selected for PRS analysis. PRS were constructed for prioritized proteins with and without the apolipoprotein E region (APOE+/-PRS) and tested for association with AD status across three cohorts (n = 6,244). An AD PRS was also tested for association with protein levels in one cohort (n = 410). Proteins showing association with AD were taken forward for MR. RESULTS: For APOE ɛ3, apolipoprotein B-100, and C-reactive protein (CRP), protein APOE+ PRS were associated with AD below Bonferroni significance (pBonf, p < 0.00017). No protein APOE- PRS or AD PRS (APOE+/-) passed pBonf. However, vitamin D-binding protein (protein PRS APOE-, p = 0.009) and insulin-like growth factor-binding protein 2 (AD APOE- PRS p = 0.025, protein APOE- PRS p = 0.045) displayed suggestive signals and were selected for MR. In bi-directional MR, none of the five proteins demonstrated a causal association (p < 0.05) in either direction. CONCLUSION: Apolipoproteins and CRP PRS are associated with AD and provide a genetic signal linked to a specific, accessible risk factor. While evidence of causality was limited, this study was conducted in a moderate sample size and provides a framework for larger samples with greater statistical power.

Performance evaluation of five lipoprotein(a) immunoassays on the Roche cobas c501 chemistry analyzer.

OBJECTIVES: Measurement of lipoprotein(a) [Lp(a)] is used in risk assessment of atherosclerotic cardiovascular disease (ASCVD). The aim of the current study was to evaluate performance characteristic of five different Lp(a) assays using the cobas c501 (Roche Diagnostics) analyzer. DESIGN AND METHODS: Lp(a) was measured using five Lp(a) assays (Diazyme, Kamiya, MedTest, Randox, and Roche) configured to mg/dL units. Assays from Diazyme and Kamiya were also configured using nmol/L units in separate experiments. Studies included sensitivity, imprecision, linearity, method comparison, and evaluation of healthy subjects. Imprecision (intra-day, 20 replicates; inter-day, duplicates twice daily for five days) and linearity were evaluated using patient pools. Linearity assessed a minimum of five patient splits spanning the analytical measurement range (AMR). Method comparison used 80 residual serum samples. Specimens from 120 self-reported healthy subjects (61 females / 59 males) were also tested. Method comparison for two assays in nmol/L units was conducted using 96 residual serum samples. RESULTS: Assay sensitivities met all manufacturer claims. Imprecision studies demonstrated %CVs ranging from 2.5 to 5.2% for the low pool (average concentration from 7.3 to 12.4 â€‹mg/dL); high pool %CVs ranged from 0.8 to 3.0% (average concentrations from 31.5-50.2 â€‹mg/dL). Linearity was confirmed for all assays. Variation in accuracy was observed when comparing results to an all method average. Lp(a) results were higher in females versus males in self-reported healthy subjects. CONCLUSIONS: All assays performed according to manufacturer described performance characteristics, although differences were observed across Lp(a) assays tested when compared to an all method average.