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.

A New Case of Abetalipoproteinemia Caused by Novel Compound Heterozygote Mutations in the MTTP Gene without Fat or Vitamin Malabsorption.

Abetalipoproteinemia (ABL) is a rare disease characterized by extremely low apolipoprotein B (apoB)-containing lipoprotein levels, dietary fat, and fat-soluble vitamin malabsorption, leading to gastrointestinal, neuromuscular, and ophthalmological symptoms. We herein report a case of ABL with novel compound heterozygous mutations in the microsomal triglyceride transfer protein gene (c.1686_1687del [p.Ser563TyrfsTer10] and c.1862T>C [p.Ile621Thr]), identified via panel sequencing. Although the patient had extremely reduced low-density lipoprotein cholesterol levels and a fatty liver, he did not exhibit other typical complications. Furthermore, unlike typical ABL, this patient had a preserved apoB-48 secretion and increased concentrations of high-density lipoprotein cholesterol, which may account for the normal serum fat-soluble vitamin levels.

Comparison of the impact of saturated fat from full-fat yogurt or low-fat yogurt and butter on cardiometabolic factors: a randomized cross-over trial.

PURPOSE: Dairy foods are often a major contributor to dietary saturated fatty acids (SFA) intake. However, different SFA-rich foods may not have the same effects on cardiovascular risk factors. We compared full-fat yogurt with low-fat yogurt and butter for their effects on cardiometabolic risk factors in healthy individuals. METHODS: Randomized, two-period crossover trial conducted from October 2022 to April 2023 among 30 healthy men and women (15 to receive full-fat yogurt first, and 15 to receive low-fat yogurt and butter first). Participants consumed a diet with 1.5-2 servings of full-fat (4%) yogurt or low-fat (< 1.5) yogurt and 10-15 g of butter per day for 4 weeks, with 4 weeks wash-out when they consumed 1.5-2 servings of low-fat milk. At baseline, and the end of each 4 weeks, fasting blood samples were drawn and plasma lipids, glycemic and inflammatory markers as well as expression of some genes in the blood buffy coats fraction were determined. RESULTS: All 30 participants completed the two periods of the study. Apolipoprotein B was higher for the low-fat yogurt and butter [changes from baseline, + 10.06 (95%CI 4.64 to 15.47)] compared with the full-fat yogurt [-4.27 (95%CI, -11.78 to 3.23)] and the difference between two treatment periods was statistically significant (p = 0.004). Non-high-density lipoprotein increased for the low-fat yogurt and butter [change, + 5.06 (95%CI (-1.56 to 11.69) compared with the full-fat yogurt [change, - 4.90 (95%CI, -11.61 to 1.81), with no significant difference between two periods (p = 0.056). There were no between-period differences in other plasma lipid, insulin, and inflammatory biomarkers or leukocyte gene expression of ATP-binding cassette transporter 1 and CD36. CONCLUSION: This study suggests that short-term intake of SFAs from full-fat yogurt compared to intake from butter and low-fat yogurt has fewer adverse effects on plasma lipid profile. CLINICALTRIALS: GOV: NCT05589350, 10/15/2022.

Haplotype analysis and linkage disequilibrium of ApoB gene polymorphisms and its relationship with hyperlipidemia in patients with acne vulgaris.

BACKGROUND: Acne vulgaris (AV) is a chronic, multifactorial inflammatory disease of the pilosebaceous unit brought on by hormonal imbalance, excessive sebum production, follicular hyperkeratinization, inflammation and Cutibacterium acne. Acne patients are characterized by alteration of the lipid profile. Apolipoprotein B gene (ApoB) plays an essential role in lipoprotein biosynthesis and multiple single-nucleotide polymorphisms (SNPs) in ApoB are associated with dyslipidemia. AIM: The aim of this study was to estimate the alteration of lipid profiles in AV, determine the genetic association with lipid profile alteration by studying the ApoB gene polymorphisms, and to identify the exact haplotypes associated with acne and lipid profile alteration. SUBJECTS AND METHODS: In a case-control study consisting of 63 non-obese acne patients and 43 healthy controls, all participants underwent biochemical, anthropological assessments, and genetic analysis for ApoB polymorphisms. RESULT: Our results indicate that serum ApoB and the lipid profile were higher in acne patients compared with healthy subject. The most common haplotypes in acne patients were rs562338 A/rs17240441 I/c.12669 A/rs1042034 G, whereas the most common haplotypes in healthy subjects were rs562338 G/rs17240441 D/c.12669 A/rs1042034 G. Patients with mild acne had higher serum ApoB levels p = 0.005. Also, the low-density lipoprotein cholesterol (LDL-C) level was higher in mild acne compared with other acne groups, with a highly significant variation of p ≤ 0.001. CONCLUSION: We found a significant variation between the acne group and healthy controls in serum ApoB, triglycerides, total cholesterol and LDL-C. The most common haplotypes in acne patients are rs562338 A/, rs17240441 I/, c.12669 A/ and rs1042034 G, and there is a linkage disequilibrium between the four selected SNPs.

Association of epistatic effects of MTHFR, ACE, APOB, and APOE gene polymorphisms with the risk of myocardial infarction and unstable angina in Egyptian patients.

Despite remarkable discoveries in the genetic susceptibility of coronary artery disease (CAD), a large part of heritability awaits identification. Epistasis or gene-gene interaction has a profound influence on CAD and might contribute to its missed genetic variability; however, this impact was largely unexplored. Here, we appraised the associations of gene-gene interactions and haplotypes of five polymorphisms, namely methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C, angiotensin converting enzyme (ACE) insertion/deletion (I/D), apolipoprotein B (APOB) R3500Q, and apolipoprotein E (APOE) ε4 with the risk of myocardial infarction (MI) and unstable angina (UA). Gene-environment interactions with traditional risk factors and clinical data were also scrutinized. This study recruited 100 MI, 50 UA patients, and 100 apparently healthy controls. Logistic regression models were employed in association analyses. We remarked that the single locus effect of individual polymorphisms was relatively weak; however, a magnified effect of their combination via gene-gene interaction may predict MI risk after adjustment for multiple comparisons. Only MTHFR C677T, ACE I/D, and APOB R5300Q were associated with the risk of UA, and the ACE I/D-R3500Q interaction posed a decreased UA risk. APOB R3500Q was in strong linkage disequilibrium with MTHFR C677T, ACE I/D, and APE ε4 polymorphisms. The TCDGε3, CADGε4, and TADGε4-C677T-A1298C-ACE I/D-R3500Q-APOE haplotypes were associated with escalating MI risk, while the CDG or CIG-C677T-ACE I/D-R3500Q haplotype was highly protective against UA risk compared to controls. Interestingly, the CADGε4 and CAIGε3 haplotypes were strongly associated with the presence of diabetes and hypertension, respectively in MI patients; both haplotypes stratified patients according to the ECHO results. In UA, the CDG haplotype was negatively associated with the presence of diabetes or dilated heart. Conclusively, our results advocate that a stronger combined effect of polymorphisms in MTHFR, ACE, APOB, and APOE genes via gene-gene and gene-environment interactions might help in risk stratification of MI and UA patients.

Effects of niacin on apo A1 and B levels: a systematic review and meta-analysis of randomised controlled trials.

Niacin has been investigated for its potential impact on lipid metabolism and cardiovascular health. This meta-analysis aims to systematically evaluate the effects of niacin interventions on apo A1 and apo B levels, key regulators of lipoprotein metabolism and markers of cardiovascular risk. A comprehensive search of the literature was performed on five databases of PubMed, Scopus, Web of Science, Embase and Cochrane library, from inception up to 15 July 2023. This search identified 1452 publications, from which twelve randomised controlled trials met the inclusion criteria. The intervention dosages ranged from 500 to 3000 mg/d, and the study durations spanned from 6 to 102·8 weeks. The niacin intervention demonstrated a significant reduction in apo B levels (weighted mean differences (WMD): -24·37 mg/dl, P = 0·01). Subgroup analyses indicated that intervention duration played a role, with trials of ≤ 16 weeks showing a greater reduction in apo B. Regarding apo A1, niacin significantly increased its levels (WMD: 8·23 mg/dl, P < 0·001). Subgroup analyses revealed that the beneficial effects of niacin on apo A1 were observed at a dosage of > 1500 mg/d (P < 0·001), and extended-release niacin was more effective compared with other forms (P < 0·001). According to the Begg's regression test, no publication bias was observed in this systematic review and meta-analysis. This meta-analysis highlights niacin's potential role in improving lipid profiles and cardiovascular health. Further well-designed clinical trials are needed to elucidate and confirm optimal dosages and durations of niacin interventions for influencing apo A1 and B.

Ae index is an independent predictor of kidney stone recurrence in overweight and obese patients.

BACKGROUND: Finding some convenient and economical indicators to initially screen overweight and obese patients at high risk of kidney stone recurrence can help them prevent stone recurrence with lower medical cost. The purpose of this article is to determine the clinical value of Ae index (Apo B × 1000/eGFR) as an independent predictor for kidney stone recurrence in overweight and obese populations. METHODS: We queried the electronic medical records of patients with kidney stone operated at our hospital from March 2016 to March 2022, and selected BMI ≥ 25 kg/m2 as the study population and divided the patients into stone recurrence group and non-recurrence group. Relevant parameters of routine blood and biochemical test, glycated serum protein (GSP), and history of hypertension and hyperglycemia were collected. Then the Chi-square test, independent samples t-test or Wilcoxon rank-sum test were used to calculate the differences between the two groups of data. Next, we performed univariate and multivariate logistic regression analysis to screen out the most significant variables Apo B and eGFR, and then we calculated the Ae index using the formula Apo B × 1000/eGFR, and analyzed the relationship between Ae index and kidney stone recurrence. RESULTS: Univariate analysis found that Apo B (OR:8.376,95%CI:3.093-22.680), Creatinine (OR:1.012,95%CI:1.003-1.021), Cystatin C(OR:2.747,95%CI:1.369-5.508), LDL-C (OR:1.588,95%CI:1.182-2.134), TC (OR:1.543,95%CI:1.198-1.988) were positively associated, eGFR (OR:0.980,95%CI:0.970-0.991) was negatively associated with kidney stone recurrence. And multivariate logistic regression analysis suggested that Apo B (OR:11.028, 95%CI:3.917-31.047) and eGFR (OR:0.976, 95%CI:0.965-0.988) were the most significant factors. Then we calculated Ae index and analyzed it, the sensitivity was 74.26% and the specificity was 60.00%, higher than either individual variable. Its smoothed curve revealed a non-linear relationship between them with the inflection point of 9.16. And the OR on the left side of the inflection point was 1.574 (95% CI: 1.228-2.018), whereas the OR on the right side of the inflection point was 1.088 (95% CI: 1.007-1.177). CONCLUSIONS: Ae index is an easily calculated and obtained index that has some predictive value for kidney stone recurrence in overweight and obese patients, which is of interest.

Postprandial Hyperlipidemia: Its Pathophysiology, Diagnosis, Atherogenesis, and Treatments.

Postprandial hyperlipidemia showing postprandial increases in serum triglyceride (TG) is associated with the development of atherosclerotic cardiovascular disease (ASCVD). To diagnose postprandial hyperlipidemia, the oral fat loading test (OFLT) should be performed; however, this test is very time-consuming and is difficult to perform. Elevated serum TG levels reflect an increase in TG-rich lipoproteins (TRLs), such as chylomicrons (CM), very low-density lipoproteins (VLDL), and their remnants (CM remnants [CMRs] and VLDL remnants [VLDLRs]). Understanding of elevation in CMR and/or VLDLR can lead us to understand the existence of postprandial hyperlipidemia. The measurement of apo B48, which is a constituent of CM and CMR; non-fasting TG, which includes TG content in all lipoproteins including CM and CMR; non-high-density lipoprotein cholesterol (non-HDL-C), which includes TRLs and low-density lipoprotein; and remnant cholesterol are useful to reveal the existence of postprandial hyperlipidemia. Postprandial hyperlipidemia is observed in patients with familial type III hyperlipoproteinemia, familial combined hyperlipidemia, chronic kidney disease, metabolic syndrome and type 2 diabetes. Postprandial hyperlipidemia is closely related to postprandial hyperglycemia, and insulin resistance may be an inducing and enhancing factor for both postprandial hyperlipidemia and postprandial hyperglycemia. Remnant lipoproteins and metabolic disorders associated with postprandial hyperlipidemia have various atherogenic properties such as induction of inflammation and endothelial dysfunction. A healthy diet, calorie restriction, weight loss, and exercise positively impact postprandial hyperlipidemia. Anti-hyperlipidemic drugs such pemafibrate, fenofibrate, bezafibrate, ezetimibe, and eicosapentaenoic acid have been shown to improve postprandial hyperlipidemia. Anti-diabetic drugs including metformin, alpha-glucosidase inhibitors, pioglitazone, dipeptidyl-peptidase-4 inhibitors and glucagon-like peptide 1 analogues have been shown to ameliorate postprandial hyperlipidemia. Although sodium glucose cotransporter-2 inhibitors have not been proven to reduce postprandial hyperlipidemia, they reduced fasting apo B48 and remnant lipoprotein cholesterol. In conclusion, it is important to appropriately understand the existence of postprandial hyperlipidemia and to connect it to optimal treatments. However, there are some problems with the diagnosis for postprandial hyperlipidemia. Postprandial hyperlipidemia cannot be specifically defined by measures such as TG levels 2 h after a meal. To study interventions for postprandial hyperlipidemia with the outcome of preventing the onset of ASCVD, it is necessary to define postprandial hyperlipidemia using reference values such as IGT.

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.

Apo B-48 gene expression and low-density lipoprotein as a factor for increased insulin resistance and severity of acne.

BACKGROUND: The contribution of insulin to acne is that it stimulates the synthesis of androgenic hormones, which are important in the development of excess sebum, hyperkeratinization, and sebaceous gland cell growth. OBJECTIVE: To ascertain whether the lipid profile abnomalies seen in acne vulgaris are genetically induced, we also seek to establish a link between insulin resistance and lipid profiles. METHODS: An analytical cross-sectional study with case-control design research investigation of 72 individuals with acne vulgaris and 72 healthy volunteers was carried out. Both groups' medical histories were taken, as were the severity and duration of the disease among acne sufferers, as well as demographic data. Anthropometry tests were performed on both groups, including their weights, height, and circumference of waist, as well as the profile of lipids, blood glucose levels after a fast, insulin levels during fasting, resistance to insulin, and Apo B-48 folding change. RESULTS: Severe acne vulgaris patients showed significantly increased TG, TC, LDL-C, blood glucose levels after a fast, fasting insulin, and resistance to insulin levels. P = 0.005 showed that Apo B-48 expression increased in patients compared to healthy people. Apo B-48 folding change and insulin resistance were found to have a substantial positive simple linear association. Acne vulgaris, whether mild, moderate, or severe, has a significant positive linear connection with insulin resistance. CONCLUSION: Acne patients had an abnormal in lipid profile. Acne individuals with severe form are more inclined to acquire resistance to insulin as well as higher glucose and insulin levels. Apo B-48 gene expression is elevated in acne individuals with severe form who have lipid abnormalities. This illustrating the importance of genetic variables in acne, insulin resistance, lipid profile modifications as well as Isotretinoin, a standard acne medication, can also cause lipid irregularities.

Effects of vitamin C supplementation on oxidative stress and serum paraoxonase/arylesterase activities in patients on long-term hemodialysis / Efectos de la suplementación con vitamina C sobre el estrés oxidativo y las actividades de paraoxonasa/arilesterasa sérica en pacientes en hemodiálisis a largo plazo

Background: Oxidative stress increases oxidizability of apolipoprotein-B containing lipoproteins and decreases paraoxonase (PON) activity in hemodialysis (HD) patients and plays an important part in the development of atherosclerotic cardiovascular diseases. In HD patients, plasma ascorbic acid (AA) levels are decreased either due to the loss by hemodialysis membranes or due to malnutrition and contribute to the imbalance of antioxidant defense mechanisms. We hypothesized that long-term ascorbic acid (AA) supplementation recovers oxidizability of lipoproteins in HD patients by reinforcing PON activity. Methods: Twenty-nine adult patients were treated with 100mg and 500mg AA at the end of each HD session thrice a week for two consecutive 16 weeks-periods, respectively. Blood samples were obtained before the first HD session and prior to the first HD sessions following the 100mg AA-supplemented and the 500mg AA-supplemented periods. Results: PON activities were significantly increased after 100mg (p<0.05) and 500mg AA (p<0.001) supplementation periods compared to the basal level. Apo-B lipoprotein oxidizability (Δ-MDA) was significantly decreased after 500mg AA supplementation compared to both basal (p<0.05) and 100mg AA supplementation periods (p<0.05). Plasma AA concentrations were negatively correlated with Δ-MDA levels (R=−0.327; p<0.01). Conclusion: Our results suggest that long-term parenteral 500mg AA supplementation improves PON activity alleviating apo B-containing lipoproteins oxidizability in HD patients. (AU)

Antecedentes: El estrés oxidativo aumenta la susceptibilidad a la oxidación de las apolipoproteínas-B que contienen lipoproteínas y reduce la actividad de paraoxonasa (PON) en pacientes de hemodiálisis (HD) formando un papel importante en el desarrollo de enfermedades arterioescleróticas cardiovasculares. En pacientes de HD, los niveles de ácido ascórbico (AA) plasmático disminuyen debido a la pérdida por membranas de hemodiálisis o por desnutrición, y contribuye al desequilibrio de los mecanismos de defensa antioxidantes. Nuestra hipótesis es que a largo plazo la suplementación con AA recupera la susceptibilidad a la oxidación de las lipoproteínas en pacientes de HD al reforzar la actividad de PON. Métodos: Se trataron 29 pacientes adultos con 100 y 500mg de AA al final de cada sesión de HD/3 veces por semana/durante 2 períodos consecutivos de 16 semanas, respectivamente. Se obtuvieron muestras de sangre antes de la primera sesión de HD y previo a las primeras sesiones de HD luego de los 100mg suplementados con AA y los periodos suplementados con 500mg de AA. Resultados: Las actividades de PON aumentaron significativamente después de los periodos de suplementación de 100mg (p<0,05) y de 500mg de AA (p<0,001) comparados con el nivel base. La susceptibilidad a la oxidación de la lipoproteína apoB (Δ-MDA) disminuyó significativamente luego de la suplementación de 500mg de AA en comparación con períodos de valores base (p<0,05) y los de 100mg de AA (p<0,05). La correlación entre las concentraciones de plasma AA y los niveles de Δ-MDA resultó negativa (R=−0,327; p<0,01). Conclusión: Nuestros resultados sugieren que la suplementación parenteral a largo plazo de 500mg de AA mejora la actividad de PON mitigando la susceptibilidad a la oxidación de las lipoproteínas que contienen apoB en pacientes en HD. (AU)

Macadamia nut effects on cardiometabolic risk factors: a randomised trial.

We sought to examine the effects of daily consumption of macadamia nuts on body weight and composition, plasma lipids and glycaemic parameters in a free-living environment in overweight and obese adults at elevated cardiometabolic risk. Utilising a randomised cross-over design, thirty-five adults with abdominal obesity consumed their usual diet plus macadamia nuts (~15 % of daily calories) for 8 weeks (intervention) and their usual diet without nuts for 8 weeks (control), with a 2-week washout. Body composition was determined by bioelectrical impedance; dietary intake was assessed with 24-h dietary recalls. Consumption of macadamia nuts led to increased total fat and MUFA intake while SFA intake was unaltered. With mixed model regression analysis, no significant changes in mean weight, BMI, waist circumference, percent body fat or glycaemic parameters, and non-significant reductions in plasma total cholesterol of 2⋅1 % (-4⋅3 mg/dl; 95 % CI -14⋅8, 6⋅1) and low-density lipoprotein (LDL-C) of 4 % (-4⋅7 mg/dl; 95 % CI -14⋅3, 4⋅8) were observed. Cholesterol-lowering effects were modified by adiposity: greater lipid lowering occurred in those with overweight v. obesity, and in those with less than the median percent body fat. Daily consumption of macadamia nuts does not lead to gains in weight or body fat under free-living conditions in overweight or obese adults; non-significant cholesterol lowering occurred without altering saturated fat intake of similar magnitude to cholesterol lowering seen with other nuts. Clinical Trial Registry Number and Website: NCT03801837 https://clinicaltrials.gov/ct2/show/NCT03801837?term = macadamia + nut&draw = 2&rank = 1.

Is hypertriglyceridemia a reliable indicator of cholesterol-depleted Apo B particles?

OBJECTIVES: Because cholesterol-depleted Apo B particles are thought to be a hallmark of hypertriglyceridemia, American, Canadian and European Lipid Guidelines suggest screening for Apo B only in patients with hypertriglyceridemia. Accordingly, this study examines the relationship of triglycerides to the LDL-C/Apo B and non-HDL-C/Apo B ratios. METHODS: The study cohort consisted of 6272 NHANES subjects adjusted for a weighted sample size of 150 million subjects without previously diagnosed cardiac disease. Data was reported by LDL-C/Apo B tertiles as weighted frequencies and percent. Sensitivity, specificity, negative predictive and positive predictive values were calculated for triglycerides thresholds of >150 mg/dL and >200 mg/dL. The range of values of Apo B for decisional levels of LDL-C and non-HDL-C were also determined RESULTS: Among patients with triglycerides >200 mg/dL, 75.9% were amongst the lowest LDL-C/Apo B tertile. However, this represents only 7.5% of the total population. Of patients with the lowest LDL-C/Apo B ratio, 59.8% had triglycerides <150 mg/dL. Moreover, there was an inverse relationship between non-HDL-C/Apo B such that elevated triglycerides were associated with the highest tertile of non-HDL-C/Apo B. Finally, the range of values of Apo B for decisional levels of LDL-C and non-HDL-C was determined and is so broad- 30.3-40.6 mg/dl Apo B for different levels of LDL-C and 19.5 to 27.6 mg/dl Apo B for different levels of non-HDL-C- that neither is an adequate clinical surrogate for Apo B. CONCLUSION: Plasma triglycerides should not be used to restrict the measurement of Apo B since cholesterol-depleted Apo B particles may be present at any level of triglyceride.

Effects of vitamin C supplementation on oxidative stress and serum paraoxonase/arylesterase activities in patients on long-term hemodialysis.

BACKGROUND: Oxidative stress increases oxidizability of apolipoprotein-B containing lipoproteins and decreases paraoxonase (PON) activity in hemodialysis (HD) patients and plays an important part in the development of atherosclerotic cardiovascular diseases. In HD patients, plasma ascorbic acid (AA) levels are decreased either due to the loss by hemodialysis membranes or due to malnutrition and contribute to the imbalance of antioxidant defense mechanisms. We hypothesized that long-term ascorbic acid (AA) supplementation recovers oxidizability of lipoproteins in HD patients by reinforcing PON activity. METHODS: Twenty-nine adult patients were treated with 100mg and 500mg AA at the end of each HD session thrice a week for two consecutive 16 weeks-periods, respectively. Blood samples were obtained before the first HD session and prior to the first HD sessions following the 100mg AA-supplemented and the 500mg AA-supplemented periods. RESULTS: PON activities were significantly increased after 100mg (p<0.05) and 500mg AA (p<0.001) supplementation periods compared to the basal level. Apo-B lipoprotein oxidizability (Δ-MDA) was significantly decreased after 500mg AA supplementation compared to both basal (p<0.05) and 100mg AA supplementation periods (p<0.05). Plasma AA concentrations were negatively correlated with Δ-MDA levels (R=-0.327; p<0.01). CONCLUSION: Our results suggest that long-term parenteral 500mg AA supplementation improves PON activity alleviating apo B-containing lipoproteins oxidizability in HD patients.

Small dense low-density lipoprotein cholesterol compared to other lipoprotein biomarkers for predicting coronary heart disease among individuals with normal fasting glucose: The Multi-Ethnic Study of Atherosclerosis.

Objective: This study compared small dense low-density lipoprotein cholesterol (sdLDL-C) with apolipoprotein B (apo B), and low-density lipoprotein particles (LDL-P) in predicting CHD risk in generally healthy adults with normal fasting glucose (NFG). Methods: This study was conducted among participants with NFG in the Multi-Ethnic Study of Atherosclerosis (MESA) prospective cohort with measurements of sdLDL-C, LDL-P, and apo B available at baseline (2000-2002) and follow-up CHD data (through 2015) (N = 3,258). Biomarkers were evaluated as quartiles, and in categories using clinically and 75th percentile-defined cut-points. Discordance/concordance of sdLDL-C relative to other biomarkers was calculated using 75th percentile cut-points and linear regression residuals. Associations between individual biomarkers, sdLDL-C discordance and CHD incidence were evaluated using Cox proportional hazards regression. Results: There were 241 incident CHD events in this population through 2015. Higher sdLDL-C, apo B, LDL-P were similarly associated with increased CHD in individuals with NFG. Discordance of sdLDL-C with apo B or LDL-P by 75th percentiles was not significantly associated with CHD. Residuals discordantly higher/lower sdLDL-C relative to apo B (discordant high HR=1.26, 95% CI: 0.89, 1.78; discordant low HR=0.94, 95% CI: 0.68, 1.29) and LDL-P (discordant high HR=1.25, 95% CI: 0.88, 1.75; discordant low HR=0.84, 95% CI:0.60, 1.16), compared to those with concordant measures, had non-statistically significant higher/lower risk of CHD. Conclusions: Results suggest sdLDL-C, apo B and LDL-P are generally comparable for predicting CHD events in normoglycemic individuals. Larger studies are needed to confirm findings and to investigate whether measurement of sdLDL-C may be beneficial to evaluate as an additional risk-enhancing factor.

Level of non-conventional lipid parameters and its comparative analysis with TSH in subclinical hypothyroidism.

OBJECTIVES: The objective of this study is to estimate lipid parameters in subclinical hypothyroidism and correlate it with TSH. METHODS: Forty newly diagnosed cases of subclinical hypothyroidism and Forty age and gender-matched healthy controls were recruited for the study. Blood samples were collected from them and serum lipid profile (i.e. HDL, LDL, TG, serum total cholesterol) of the subjects was estimated by standard photometric methods in a fully auto-analyzer (MINDRAY BS-300) using commercially available kits and VLDL cholesterol was calculated using the Friedewald's formula. While serum Ox-LDL, Lipoprotein A, Apolipoprotein A1 and Apo B were estimated by using commercial kit based on enzyme-linked immmunosorbent assay. RESULTS: The parameters such as Oxidized low-density lipoprotein (Ox-LDL), lipoprotein (a), apolipoprotein A1, apolipoprotein B and small dense lipoprotein (sd LDL) were significantly increased in subclinical hypothyroid cases when compared with the control subjects (p<0.0001). In present study results showed significant positive correlations of serum thyroid stimulating hormone (TSH) with Ox-LDL (r=0.85, p<0.01), sd LDL (r=0.71, p<0.01). CONCLUSIONS: The present study focuses on the role of Ox-LDL, sd-LDL Lipoprotein A, Apolipoprotein A1 and Apo B that are sensitive indicators of atherogenic dyslipidemia in subclinical hypothyroidism and can serve as a better & novel risk factor for CAD.

Modulation of Dyslipidemia Markers Apo B/Apo A and Triglycerides/HDL-Cholesterol Ratios by Low-Carbohydrate High-Fat Diet in a Rat Model of Metabolic Syndrome.

Metabolic syndrome (MetS) risks cardiovascular diseases due to its associated Dyslipidemia. It is proposed that a low-carbohydrate, high-fat (LCHF) diet positively ameliorates the MetS and reverses insulin resistance. Therefore, we aimed to investigate the protecting effect of the LCHF diet on MetS-associated Dyslipidemia in an experimental animal model. Forty male Sprague-Dawley rats were divided into four groups (10/group): the control group, dexamethasone-induced MetS (DEX) (250 µg/kg/day), LCHF-fed MetS group (DEX + LCHF), and High-Carbohydrate-Low-Fat-fed MetS group (DEX + HCLF). At the end of the four-week experiment, fasting glucose, insulin, lipid profile (LDL-C, HDL-C, Triglyceride), oxidized-LDL, and small dense-LDL using the ELISA technique were estimated. HOMA-IR, Apo B/Apo A1 ratio, and TG/HDL were calculated. Moreover, histological examination of the liver by H & E and Sudan III stain was carried out. In the DEX group, rats showed a significant (p < 0.05) increase in the HOMA-IR, atherogenic parameters, such as s-LDL, OX-LDL, Apo B/Apo A1 ratio, and TG/HDL. The LCHF diet significantly improved the parameters of Dyslipidemia (p < 0.05) by decreasing the Apo B/Apo A1 and TG/HDL-C ratios. Decreased steatosis in LCHF-fed rats compared to HCLF was also revealed. In conclusion, the LCHF diet ameliorates MetS-associated Dyslipidemia, as noted from biochemical results and histological examination.

PSRC1 May Affect Coronary Artery Disease Risk by Altering CELSR2, PSRC1, and SORT1 Gene Expression and Circulating Granulin and Apolipoprotein B Protein Levels.

OBJECTIVE: The aim of the study was to identify additional factors that contributed to coronary artery disease (CAD). METHODS: We conducted integrative analysis on publicly available data from genome-wide association studies and quantitative trait locus studies by employing Mendelian randomization methods to examine the associations of gene expression in liver cells and circulating protein levels with LDL-C and CAD. RESULTS: We found that the mRNA expression levels of CELSR2, PSRC1, SORT1, SYPL2, RHD, RHCE, ANGPTL3, ATXN7L2, DNAH11, FADS3, ST3GAL4, NYNRIN, CETP, EFCAB13, and SPTLC3 were significantly associated with LDL-C. The expression levels of SORT1, PSRC1, and CELSR2 in liver cells were significantly associated with CAD. Higher expression levels of SORT1, PSRC1, and CELSR2 in the liver were significantly associated with lower circulating LDL-C levels and CAD risk. PSRC1 variants were strongly associated with SORT1, PSRC1, and CELSR2 gene expression in liver cells. Higher circulating granulin and apolipoprotein B levels, which were strongly affected by PSRC1 variants, were significantly associated with higher LDL-C levels and CAD risk, with odds ratios of 1.15 (1.10-1.19) and 1.45 (1.21-1.74), respectively. CONCLUSION: This study showed that regulatory SNPs in PSRC1 may affect CAD risk by altering CELSR2, PSRC1, and SORT1 gene expression in liver cells and circulating granulins and apolipoprotein B proteins.

Effects of diets rich in ghee or olive oil on cardiometabolic risk factors in healthy adults: a two-period, crossover, randomised trial.

This study aimed to evaluate the cardiovascular health-related effects of consuming ghee in the usual diet. Thirty healthy men and women were studied in a free-living outpatient regimen. The participants were instructed for the isoenergetic inclusion of ghee or olive oil in their diets for 4 weeks using a randomised crossover design. At the end of run-in (baseline), 2-week wash-out and interventions, fasting blood samples were drawn. In addition, 2-h postprandial blood samples were collected after ingestion of a meal containing olive oil or ghee at week 4 of each dietary intervention. Body weight was not different between the two interventions. Compared with the olive oil, the diet with ghee increased fasting plasma apo-B (apo B) (0·09, 95 % CI 0·02, 0·17 g/l, P = 0·018), non-HDL-cholesterol (non-HDL-cholesterol) (0·53, 95 % CI 0·01, 1·05 mmol/l, P = 0·046) and LDL-cholesterol did not differ significantly between diet groups (0·29, 95 % CI -0·05, 0·63 mmol/l, P = 0·092), but had no significant effect on total cholesterol:HDL-cholesterol ratio (0·75, 95 % CI - 0·24 to 1·74 mmol/l, P = 0·118). No significant difference was observed in fasting as well as 2-h postprandial plasma TAG, glucose, insulin and plasminogen activator inhibitor-1 concentrations. This study showed that ghee that is predominantly saturated fats had an increasing effect on plasma apo B and non-HDL-cholesterol compared with olive oil, adding further evidence to the existing recommendations to replace dietary fats high in SFA with dietary fats high in unsaturated fats to reduce CVD risk.

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.